Obsidian/.obsidian/plugins/obsidian-timelines/main.js

'use strict';

var obsidian = require('obsidian');
var require$$0 = require('crypto');

function _interopDefaultLegacy (e) { return e && typeof e === 'object' && 'default' in e ? e : { 'default': e }; }

var require$$0__default = /*#__PURE__*/_interopDefaultLegacy(require$$0);

/*! *****************************************************************************
Copyright (c) Microsoft Corporation.

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
***************************************************************************** */

function __awaiter(thisArg, _arguments, P, generator) {
    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
}

const DEFAULT_SETTINGS = {
    timelineTag: 'timeline',
    sortDirection: true
};
const RENDER_TIMELINE = /<!--TIMELINE BEGIN tags=['"]([^"]*?)['"]-->(.*)+?<!--TIMELINE END-->/im;

class TimelinesSettingTab extends obsidian.PluginSettingTab {
    constructor(app, plugin) {
        super(app, plugin);
        this.plugin = plugin;
    }
    display() {
        let { containerEl } = this;
        containerEl.empty();
        containerEl.createEl('h2', { text: 'Obsidian Timelines Settings' });
        new obsidian.Setting(containerEl)
            .setName('Default timeline tag')
            .setDesc("Tag to specify which notes to include in created timelines e.g. timeline for #timeline tag")
            .addText(text => text
            .setPlaceholder(this.plugin.settings.timelineTag)
            .onChange((value) => __awaiter(this, void 0, void 0, function* () {
            this.plugin.settings.timelineTag = value;
            yield this.plugin.saveSettings();
        })));
        new obsidian.Setting(containerEl)
            .setName('Chronological Direction')
            .setDesc('Default: OLD -> NEW. Turn this setting off: NEW -> OLD')
            .addToggle((toggle) => {
            toggle.setValue(this.plugin.settings.sortDirection);
            toggle.onChange((value) => __awaiter(this, void 0, void 0, function* () {
                this.plugin.settings.sortDirection = value;
                yield this.plugin.saveSettings();
            }));
        });
    }
}

var commonjsGlobal = typeof globalThis !== 'undefined' ? globalThis : typeof window !== 'undefined' ? window : typeof global !== 'undefined' ? global : typeof self !== 'undefined' ? self : {};

function createCommonjsModule(fn, basedir, module) {
	return module = {
		path: basedir,
		exports: {},
		require: function (path, base) {
			return commonjsRequire(path, (base === undefined || base === null) ? module.path : base);
		}
	}, fn(module, module.exports), module.exports;
}

function commonjsRequire () {
	throw new Error('Dynamic requires are not currently supported by @rollup/plugin-commonjs');
}

var moment = createCommonjsModule(function (module, exports) {
(function (global, factory) {
    module.exports = factory() ;
}(commonjsGlobal, (function () {
    var hookCallback;

    function hooks() {
        return hookCallback.apply(null, arguments);
    }

    // This is done to register the method called with moment()
    // without creating circular dependencies.
    function setHookCallback(callback) {
        hookCallback = callback;
    }

    function isArray(input) {
        return (
            input instanceof Array ||
            Object.prototype.toString.call(input) === '[object Array]'
        );
    }

    function isObject(input) {
        // IE8 will treat undefined and null as object if it wasn't for
        // input != null
        return (
            input != null &&
            Object.prototype.toString.call(input) === '[object Object]'
        );
    }

    function hasOwnProp(a, b) {
        return Object.prototype.hasOwnProperty.call(a, b);
    }

    function isObjectEmpty(obj) {
        if (Object.getOwnPropertyNames) {
            return Object.getOwnPropertyNames(obj).length === 0;
        } else {
            var k;
            for (k in obj) {
                if (hasOwnProp(obj, k)) {
                    return false;
                }
            }
            return true;
        }
    }

    function isUndefined(input) {
        return input === void 0;
    }

    function isNumber(input) {
        return (
            typeof input === 'number' ||
            Object.prototype.toString.call(input) === '[object Number]'
        );
    }

    function isDate(input) {
        return (
            input instanceof Date ||
            Object.prototype.toString.call(input) === '[object Date]'
        );
    }

    function map(arr, fn) {
        var res = [],
            i;
        for (i = 0; i < arr.length; ++i) {
            res.push(fn(arr[i], i));
        }
        return res;
    }

    function extend(a, b) {
        for (var i in b) {
            if (hasOwnProp(b, i)) {
                a[i] = b[i];
            }
        }

        if (hasOwnProp(b, 'toString')) {
            a.toString = b.toString;
        }

        if (hasOwnProp(b, 'valueOf')) {
            a.valueOf = b.valueOf;
        }

        return a;
    }

    function createUTC(input, format, locale, strict) {
        return createLocalOrUTC(input, format, locale, strict, true).utc();
    }

    function defaultParsingFlags() {
        // We need to deep clone this object.
        return {
            empty: false,
            unusedTokens: [],
            unusedInput: [],
            overflow: -2,
            charsLeftOver: 0,
            nullInput: false,
            invalidEra: null,
            invalidMonth: null,
            invalidFormat: false,
            userInvalidated: false,
            iso: false,
            parsedDateParts: [],
            era: null,
            meridiem: null,
            rfc2822: false,
            weekdayMismatch: false,
        };
    }

    function getParsingFlags(m) {
        if (m._pf == null) {
            m._pf = defaultParsingFlags();
        }
        return m._pf;
    }

    var some;
    if (Array.prototype.some) {
        some = Array.prototype.some;
    } else {
        some = function (fun) {
            var t = Object(this),
                len = t.length >>> 0,
                i;

            for (i = 0; i < len; i++) {
                if (i in t && fun.call(this, t[i], i, t)) {
                    return true;
                }
            }

            return false;
        };
    }

    function isValid(m) {
        if (m._isValid == null) {
            var flags = getParsingFlags(m),
                parsedParts = some.call(flags.parsedDateParts, function (i) {
                    return i != null;
                }),
                isNowValid =
                    !isNaN(m._d.getTime()) &&
                    flags.overflow < 0 &&
                    !flags.empty &&
                    !flags.invalidEra &&
                    !flags.invalidMonth &&
                    !flags.invalidWeekday &&
                    !flags.weekdayMismatch &&
                    !flags.nullInput &&
                    !flags.invalidFormat &&
                    !flags.userInvalidated &&
                    (!flags.meridiem || (flags.meridiem && parsedParts));

            if (m._strict) {
                isNowValid =
                    isNowValid &&
                    flags.charsLeftOver === 0 &&
                    flags.unusedTokens.length === 0 &&
                    flags.bigHour === undefined;
            }

            if (Object.isFrozen == null || !Object.isFrozen(m)) {
                m._isValid = isNowValid;
            } else {
                return isNowValid;
            }
        }
        return m._isValid;
    }

    function createInvalid(flags) {
        var m = createUTC(NaN);
        if (flags != null) {
            extend(getParsingFlags(m), flags);
        } else {
            getParsingFlags(m).userInvalidated = true;
        }

        return m;
    }

    // Plugins that add properties should also add the key here (null value),
    // so we can properly clone ourselves.
    var momentProperties = (hooks.momentProperties = []),
        updateInProgress = false;

    function copyConfig(to, from) {
        var i, prop, val;

        if (!isUndefined(from._isAMomentObject)) {
            to._isAMomentObject = from._isAMomentObject;
        }
        if (!isUndefined(from._i)) {
            to._i = from._i;
        }
        if (!isUndefined(from._f)) {
            to._f = from._f;
        }
        if (!isUndefined(from._l)) {
            to._l = from._l;
        }
        if (!isUndefined(from._strict)) {
            to._strict = from._strict;
        }
        if (!isUndefined(from._tzm)) {
            to._tzm = from._tzm;
        }
        if (!isUndefined(from._isUTC)) {
            to._isUTC = from._isUTC;
        }
        if (!isUndefined(from._offset)) {
            to._offset = from._offset;
        }
        if (!isUndefined(from._pf)) {
            to._pf = getParsingFlags(from);
        }
        if (!isUndefined(from._locale)) {
            to._locale = from._locale;
        }

        if (momentProperties.length > 0) {
            for (i = 0; i < momentProperties.length; i++) {
                prop = momentProperties[i];
                val = from[prop];
                if (!isUndefined(val)) {
                    to[prop] = val;
                }
            }
        }

        return to;
    }

    // Moment prototype object
    function Moment(config) {
        copyConfig(this, config);
        this._d = new Date(config._d != null ? config._d.getTime() : NaN);
        if (!this.isValid()) {
            this._d = new Date(NaN);
        }
        // Prevent infinite loop in case updateOffset creates new moment
        // objects.
        if (updateInProgress === false) {
            updateInProgress = true;
            hooks.updateOffset(this);
            updateInProgress = false;
        }
    }

    function isMoment(obj) {
        return (
            obj instanceof Moment || (obj != null && obj._isAMomentObject != null)
        );
    }

    function warn(msg) {
        if (
            hooks.suppressDeprecationWarnings === false &&
            typeof console !== 'undefined' &&
            console.warn
        ) {
            console.warn('Deprecation warning: ' + msg);
        }
    }

    function deprecate(msg, fn) {
        var firstTime = true;

        return extend(function () {
            if (hooks.deprecationHandler != null) {
                hooks.deprecationHandler(null, msg);
            }
            if (firstTime) {
                var args = [],
                    arg,
                    i,
                    key;
                for (i = 0; i < arguments.length; i++) {
                    arg = '';
                    if (typeof arguments[i] === 'object') {
                        arg += '\n[' + i + '] ';
                        for (key in arguments[0]) {
                            if (hasOwnProp(arguments[0], key)) {
                                arg += key + ': ' + arguments[0][key] + ', ';
                            }
                        }
                        arg = arg.slice(0, -2); // Remove trailing comma and space
                    } else {
                        arg = arguments[i];
                    }
                    args.push(arg);
                }
                warn(
                    msg +
                        '\nArguments: ' +
                        Array.prototype.slice.call(args).join('') +
                        '\n' +
                        new Error().stack
                );
                firstTime = false;
            }
            return fn.apply(this, arguments);
        }, fn);
    }

    var deprecations = {};

    function deprecateSimple(name, msg) {
        if (hooks.deprecationHandler != null) {
            hooks.deprecationHandler(name, msg);
        }
        if (!deprecations[name]) {
            warn(msg);
            deprecations[name] = true;
        }
    }

    hooks.suppressDeprecationWarnings = false;
    hooks.deprecationHandler = null;

    function isFunction(input) {
        return (
            (typeof Function !== 'undefined' && input instanceof Function) ||
            Object.prototype.toString.call(input) === '[object Function]'
        );
    }

    function set(config) {
        var prop, i;
        for (i in config) {
            if (hasOwnProp(config, i)) {
                prop = config[i];
                if (isFunction(prop)) {
                    this[i] = prop;
                } else {
                    this['_' + i] = prop;
                }
            }
        }
        this._config = config;
        // Lenient ordinal parsing accepts just a number in addition to
        // number + (possibly) stuff coming from _dayOfMonthOrdinalParse.
        // TODO: Remove "ordinalParse" fallback in next major release.
        this._dayOfMonthOrdinalParseLenient = new RegExp(
            (this._dayOfMonthOrdinalParse.source || this._ordinalParse.source) +
                '|' +
                /\d{1,2}/.source
        );
    }

    function mergeConfigs(parentConfig, childConfig) {
        var res = extend({}, parentConfig),
            prop;
        for (prop in childConfig) {
            if (hasOwnProp(childConfig, prop)) {
                if (isObject(parentConfig[prop]) && isObject(childConfig[prop])) {
                    res[prop] = {};
                    extend(res[prop], parentConfig[prop]);
                    extend(res[prop], childConfig[prop]);
                } else if (childConfig[prop] != null) {
                    res[prop] = childConfig[prop];
                } else {
                    delete res[prop];
                }
            }
        }
        for (prop in parentConfig) {
            if (
                hasOwnProp(parentConfig, prop) &&
                !hasOwnProp(childConfig, prop) &&
                isObject(parentConfig[prop])
            ) {
                // make sure changes to properties don't modify parent config
                res[prop] = extend({}, res[prop]);
            }
        }
        return res;
    }

    function Locale(config) {
        if (config != null) {
            this.set(config);
        }
    }

    var keys;

    if (Object.keys) {
        keys = Object.keys;
    } else {
        keys = function (obj) {
            var i,
                res = [];
            for (i in obj) {
                if (hasOwnProp(obj, i)) {
                    res.push(i);
                }
            }
            return res;
        };
    }

    var defaultCalendar = {
        sameDay: '[Today at] LT',
        nextDay: '[Tomorrow at] LT',
        nextWeek: 'dddd [at] LT',
        lastDay: '[Yesterday at] LT',
        lastWeek: '[Last] dddd [at] LT',
        sameElse: 'L',
    };

    function calendar(key, mom, now) {
        var output = this._calendar[key] || this._calendar['sameElse'];
        return isFunction(output) ? output.call(mom, now) : output;
    }

    function zeroFill(number, targetLength, forceSign) {
        var absNumber = '' + Math.abs(number),
            zerosToFill = targetLength - absNumber.length,
            sign = number >= 0;
        return (
            (sign ? (forceSign ? '+' : '') : '-') +
            Math.pow(10, Math.max(0, zerosToFill)).toString().substr(1) +
            absNumber
        );
    }

    var formattingTokens = /(\[[^\[]*\])|(\\)?([Hh]mm(ss)?|Mo|MM?M?M?|Do|DDDo|DD?D?D?|ddd?d?|do?|w[o|w]?|W[o|W]?|Qo?|N{1,5}|YYYYYY|YYYYY|YYYY|YY|y{2,4}|yo?|gg(ggg?)?|GG(GGG?)?|e|E|a|A|hh?|HH?|kk?|mm?|ss?|S{1,9}|x|X|zz?|ZZ?|.)/g,
        localFormattingTokens = /(\[[^\[]*\])|(\\)?(LTS|LT|LL?L?L?|l{1,4})/g,
        formatFunctions = {},
        formatTokenFunctions = {};

    // token:    'M'
    // padded:   ['MM', 2]
    // ordinal:  'Mo'
    // callback: function () { this.month() + 1 }
    function addFormatToken(token, padded, ordinal, callback) {
        var func = callback;
        if (typeof callback === 'string') {
            func = function () {
                return this[callback]();
            };
        }
        if (token) {
            formatTokenFunctions[token] = func;
        }
        if (padded) {
            formatTokenFunctions[padded[0]] = function () {
                return zeroFill(func.apply(this, arguments), padded[1], padded[2]);
            };
        }
        if (ordinal) {
            formatTokenFunctions[ordinal] = function () {
                return this.localeData().ordinal(
                    func.apply(this, arguments),
                    token
                );
            };
        }
    }

    function removeFormattingTokens(input) {
        if (input.match(/\[[\s\S]/)) {
            return input.replace(/^\[|\]$/g, '');
        }
        return input.replace(/\\/g, '');
    }

    function makeFormatFunction(format) {
        var array = format.match(formattingTokens),
            i,
            length;

        for (i = 0, length = array.length; i < length; i++) {
            if (formatTokenFunctions[array[i]]) {
                array[i] = formatTokenFunctions[array[i]];
            } else {
                array[i] = removeFormattingTokens(array[i]);
            }
        }

        return function (mom) {
            var output = '',
                i;
            for (i = 0; i < length; i++) {
                output += isFunction(array[i])
                    ? array[i].call(mom, format)
                    : array[i];
            }
            return output;
        };
    }

    // format date using native date object
    function formatMoment(m, format) {
        if (!m.isValid()) {
            return m.localeData().invalidDate();
        }

        format = expandFormat(format, m.localeData());
        formatFunctions[format] =
            formatFunctions[format] || makeFormatFunction(format);

        return formatFunctions[format](m);
    }

    function expandFormat(format, locale) {
        var i = 5;

        function replaceLongDateFormatTokens(input) {
            return locale.longDateFormat(input) || input;
        }

        localFormattingTokens.lastIndex = 0;
        while (i >= 0 && localFormattingTokens.test(format)) {
            format = format.replace(
                localFormattingTokens,
                replaceLongDateFormatTokens
            );
            localFormattingTokens.lastIndex = 0;
            i -= 1;
        }

        return format;
    }

    var defaultLongDateFormat = {
        LTS: 'h:mm:ss A',
        LT: 'h:mm A',
        L: 'MM/DD/YYYY',
        LL: 'MMMM D, YYYY',
        LLL: 'MMMM D, YYYY h:mm A',
        LLLL: 'dddd, MMMM D, YYYY h:mm A',
    };

    function longDateFormat(key) {
        var format = this._longDateFormat[key],
            formatUpper = this._longDateFormat[key.toUpperCase()];

        if (format || !formatUpper) {
            return format;
        }

        this._longDateFormat[key] = formatUpper
            .match(formattingTokens)
            .map(function (tok) {
                if (
                    tok === 'MMMM' ||
                    tok === 'MM' ||
                    tok === 'DD' ||
                    tok === 'dddd'
                ) {
                    return tok.slice(1);
                }
                return tok;
            })
            .join('');

        return this._longDateFormat[key];
    }

    var defaultInvalidDate = 'Invalid date';

    function invalidDate() {
        return this._invalidDate;
    }

    var defaultOrdinal = '%d',
        defaultDayOfMonthOrdinalParse = /\d{1,2}/;

    function ordinal(number) {
        return this._ordinal.replace('%d', number);
    }

    var defaultRelativeTime = {
        future: 'in %s',
        past: '%s ago',
        s: 'a few seconds',
        ss: '%d seconds',
        m: 'a minute',
        mm: '%d minutes',
        h: 'an hour',
        hh: '%d hours',
        d: 'a day',
        dd: '%d days',
        w: 'a week',
        ww: '%d weeks',
        M: 'a month',
        MM: '%d months',
        y: 'a year',
        yy: '%d years',
    };

    function relativeTime(number, withoutSuffix, string, isFuture) {
        var output = this._relativeTime[string];
        return isFunction(output)
            ? output(number, withoutSuffix, string, isFuture)
            : output.replace(/%d/i, number);
    }

    function pastFuture(diff, output) {
        var format = this._relativeTime[diff > 0 ? 'future' : 'past'];
        return isFunction(format) ? format(output) : format.replace(/%s/i, output);
    }

    var aliases = {};

    function addUnitAlias(unit, shorthand) {
        var lowerCase = unit.toLowerCase();
        aliases[lowerCase] = aliases[lowerCase + 's'] = aliases[shorthand] = unit;
    }

    function normalizeUnits(units) {
        return typeof units === 'string'
            ? aliases[units] || aliases[units.toLowerCase()]
            : undefined;
    }

    function normalizeObjectUnits(inputObject) {
        var normalizedInput = {},
            normalizedProp,
            prop;

        for (prop in inputObject) {
            if (hasOwnProp(inputObject, prop)) {
                normalizedProp = normalizeUnits(prop);
                if (normalizedProp) {
                    normalizedInput[normalizedProp] = inputObject[prop];
                }
            }
        }

        return normalizedInput;
    }

    var priorities = {};

    function addUnitPriority(unit, priority) {
        priorities[unit] = priority;
    }

    function getPrioritizedUnits(unitsObj) {
        var units = [],
            u;
        for (u in unitsObj) {
            if (hasOwnProp(unitsObj, u)) {
                units.push({ unit: u, priority: priorities[u] });
            }
        }
        units.sort(function (a, b) {
            return a.priority - b.priority;
        });
        return units;
    }

    function isLeapYear(year) {
        return (year % 4 === 0 && year % 100 !== 0) || year % 400 === 0;
    }

    function absFloor(number) {
        if (number < 0) {
            // -0 -> 0
            return Math.ceil(number) || 0;
        } else {
            return Math.floor(number);
        }
    }

    function toInt(argumentForCoercion) {
        var coercedNumber = +argumentForCoercion,
            value = 0;

        if (coercedNumber !== 0 && isFinite(coercedNumber)) {
            value = absFloor(coercedNumber);
        }

        return value;
    }

    function makeGetSet(unit, keepTime) {
        return function (value) {
            if (value != null) {
                set$1(this, unit, value);
                hooks.updateOffset(this, keepTime);
                return this;
            } else {
                return get(this, unit);
            }
        };
    }

    function get(mom, unit) {
        return mom.isValid()
            ? mom._d['get' + (mom._isUTC ? 'UTC' : '') + unit]()
            : NaN;
    }

    function set$1(mom, unit, value) {
        if (mom.isValid() && !isNaN(value)) {
            if (
                unit === 'FullYear' &&
                isLeapYear(mom.year()) &&
                mom.month() === 1 &&
                mom.date() === 29
            ) {
                value = toInt(value);
                mom._d['set' + (mom._isUTC ? 'UTC' : '') + unit](
                    value,
                    mom.month(),
                    daysInMonth(value, mom.month())
                );
            } else {
                mom._d['set' + (mom._isUTC ? 'UTC' : '') + unit](value);
            }
        }
    }

    // MOMENTS

    function stringGet(units) {
        units = normalizeUnits(units);
        if (isFunction(this[units])) {
            return this[units]();
        }
        return this;
    }

    function stringSet(units, value) {
        if (typeof units === 'object') {
            units = normalizeObjectUnits(units);
            var prioritized = getPrioritizedUnits(units),
                i;
            for (i = 0; i < prioritized.length; i++) {
                this[prioritized[i].unit](units[prioritized[i].unit]);
            }
        } else {
            units = normalizeUnits(units);
            if (isFunction(this[units])) {
                return this[units](value);
            }
        }
        return this;
    }

    var match1 = /\d/, //       0 - 9
        match2 = /\d\d/, //      00 - 99
        match3 = /\d{3}/, //     000 - 999
        match4 = /\d{4}/, //    0000 - 9999
        match6 = /[+-]?\d{6}/, // -999999 - 999999
        match1to2 = /\d\d?/, //       0 - 99
        match3to4 = /\d\d\d\d?/, //     999 - 9999
        match5to6 = /\d\d\d\d\d\d?/, //   99999 - 999999
        match1to3 = /\d{1,3}/, //       0 - 999
        match1to4 = /\d{1,4}/, //       0 - 9999
        match1to6 = /[+-]?\d{1,6}/, // -999999 - 999999
        matchUnsigned = /\d+/, //       0 - inf
        matchSigned = /[+-]?\d+/, //    -inf - inf
        matchOffset = /Z|[+-]\d\d:?\d\d/gi, // +00:00 -00:00 +0000 -0000 or Z
        matchShortOffset = /Z|[+-]\d\d(?::?\d\d)?/gi, // +00 -00 +00:00 -00:00 +0000 -0000 or Z
        matchTimestamp = /[+-]?\d+(\.\d{1,3})?/, // 123456789 123456789.123
        // any word (or two) characters or numbers including two/three word month in arabic.
        // includes scottish gaelic two word and hyphenated months
        matchWord = /[0-9]{0,256}['a-z\u00A0-\u05FF\u0700-\uD7FF\uF900-\uFDCF\uFDF0-\uFF07\uFF10-\uFFEF]{1,256}|[\u0600-\u06FF\/]{1,256}(\s*?[\u0600-\u06FF]{1,256}){1,2}/i,
        regexes;

    regexes = {};

    function addRegexToken(token, regex, strictRegex) {
        regexes[token] = isFunction(regex)
            ? regex
            : function (isStrict, localeData) {
                  return isStrict && strictRegex ? strictRegex : regex;
              };
    }

    function getParseRegexForToken(token, config) {
        if (!hasOwnProp(regexes, token)) {
            return new RegExp(unescapeFormat(token));
        }

        return regexes[token](config._strict, config._locale);
    }

    // Code from http://stackoverflow.com/questions/3561493/is-there-a-regexp-escape-function-in-javascript
    function unescapeFormat(s) {
        return regexEscape(
            s
                .replace('\\', '')
                .replace(/\\(\[)|\\(\])|\[([^\]\[]*)\]|\\(.)/g, function (
                    matched,
                    p1,
                    p2,
                    p3,
                    p4
                ) {
                    return p1 || p2 || p3 || p4;
                })
        );
    }

    function regexEscape(s) {
        return s.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
    }

    var tokens = {};

    function addParseToken(token, callback) {
        var i,
            func = callback;
        if (typeof token === 'string') {
            token = [token];
        }
        if (isNumber(callback)) {
            func = function (input, array) {
                array[callback] = toInt(input);
            };
        }
        for (i = 0; i < token.length; i++) {
            tokens[token[i]] = func;
        }
    }

    function addWeekParseToken(token, callback) {
        addParseToken(token, function (input, array, config, token) {
            config._w = config._w || {};
            callback(input, config._w, config, token);
        });
    }

    function addTimeToArrayFromToken(token, input, config) {
        if (input != null && hasOwnProp(tokens, token)) {
            tokens[token](input, config._a, config, token);
        }
    }

    var YEAR = 0,
        MONTH = 1,
        DATE = 2,
        HOUR = 3,
        MINUTE = 4,
        SECOND = 5,
        MILLISECOND = 6,
        WEEK = 7,
        WEEKDAY = 8;

    function mod(n, x) {
        return ((n % x) + x) % x;
    }

    var indexOf;

    if (Array.prototype.indexOf) {
        indexOf = Array.prototype.indexOf;
    } else {
        indexOf = function (o) {
            // I know
            var i;
            for (i = 0; i < this.length; ++i) {
                if (this[i] === o) {
                    return i;
                }
            }
            return -1;
        };
    }

    function daysInMonth(year, month) {
        if (isNaN(year) || isNaN(month)) {
            return NaN;
        }
        var modMonth = mod(month, 12);
        year += (month - modMonth) / 12;
        return modMonth === 1
            ? isLeapYear(year)
                ? 29
                : 28
            : 31 - ((modMonth % 7) % 2);
    }

    // FORMATTING

    addFormatToken('M', ['MM', 2], 'Mo', function () {
        return this.month() + 1;
    });

    addFormatToken('MMM', 0, 0, function (format) {
        return this.localeData().monthsShort(this, format);
    });

    addFormatToken('MMMM', 0, 0, function (format) {
        return this.localeData().months(this, format);
    });

    // ALIASES

    addUnitAlias('month', 'M');

    // PRIORITY

    addUnitPriority('month', 8);

    // PARSING

    addRegexToken('M', match1to2);
    addRegexToken('MM', match1to2, match2);
    addRegexToken('MMM', function (isStrict, locale) {
        return locale.monthsShortRegex(isStrict);
    });
    addRegexToken('MMMM', function (isStrict, locale) {
        return locale.monthsRegex(isStrict);
    });

    addParseToken(['M', 'MM'], function (input, array) {
        array[MONTH] = toInt(input) - 1;
    });

    addParseToken(['MMM', 'MMMM'], function (input, array, config, token) {
        var month = config._locale.monthsParse(input, token, config._strict);
        // if we didn't find a month name, mark the date as invalid.
        if (month != null) {
            array[MONTH] = month;
        } else {
            getParsingFlags(config).invalidMonth = input;
        }
    });

    // LOCALES

    var defaultLocaleMonths = 'January_February_March_April_May_June_July_August_September_October_November_December'.split(
            '_'
        ),
        defaultLocaleMonthsShort = 'Jan_Feb_Mar_Apr_May_Jun_Jul_Aug_Sep_Oct_Nov_Dec'.split(
            '_'
        ),
        MONTHS_IN_FORMAT = /D[oD]?(\[[^\[\]]*\]|\s)+MMMM?/,
        defaultMonthsShortRegex = matchWord,
        defaultMonthsRegex = matchWord;

    function localeMonths(m, format) {
        if (!m) {
            return isArray(this._months)
                ? this._months
                : this._months['standalone'];
        }
        return isArray(this._months)
            ? this._months[m.month()]
            : this._months[
                  (this._months.isFormat || MONTHS_IN_FORMAT).test(format)
                      ? 'format'
                      : 'standalone'
              ][m.month()];
    }

    function localeMonthsShort(m, format) {
        if (!m) {
            return isArray(this._monthsShort)
                ? this._monthsShort
                : this._monthsShort['standalone'];
        }
        return isArray(this._monthsShort)
            ? this._monthsShort[m.month()]
            : this._monthsShort[
                  MONTHS_IN_FORMAT.test(format) ? 'format' : 'standalone'
              ][m.month()];
    }

    function handleStrictParse(monthName, format, strict) {
        var i,
            ii,
            mom,
            llc = monthName.toLocaleLowerCase();
        if (!this._monthsParse) {
            // this is not used
            this._monthsParse = [];
            this._longMonthsParse = [];
            this._shortMonthsParse = [];
            for (i = 0; i < 12; ++i) {
                mom = createUTC([2000, i]);
                this._shortMonthsParse[i] = this.monthsShort(
                    mom,
                    ''
                ).toLocaleLowerCase();
                this._longMonthsParse[i] = this.months(mom, '').toLocaleLowerCase();
            }
        }

        if (strict) {
            if (format === 'MMM') {
                ii = indexOf.call(this._shortMonthsParse, llc);
                return ii !== -1 ? ii : null;
            } else {
                ii = indexOf.call(this._longMonthsParse, llc);
                return ii !== -1 ? ii : null;
            }
        } else {
            if (format === 'MMM') {
                ii = indexOf.call(this._shortMonthsParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._longMonthsParse, llc);
                return ii !== -1 ? ii : null;
            } else {
                ii = indexOf.call(this._longMonthsParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._shortMonthsParse, llc);
                return ii !== -1 ? ii : null;
            }
        }
    }

    function localeMonthsParse(monthName, format, strict) {
        var i, mom, regex;

        if (this._monthsParseExact) {
            return handleStrictParse.call(this, monthName, format, strict);
        }

        if (!this._monthsParse) {
            this._monthsParse = [];
            this._longMonthsParse = [];
            this._shortMonthsParse = [];
        }

        // TODO: add sorting
        // Sorting makes sure if one month (or abbr) is a prefix of another
        // see sorting in computeMonthsParse
        for (i = 0; i < 12; i++) {
            // make the regex if we don't have it already
            mom = createUTC([2000, i]);
            if (strict && !this._longMonthsParse[i]) {
                this._longMonthsParse[i] = new RegExp(
                    '^' + this.months(mom, '').replace('.', '') + '$',
                    'i'
                );
                this._shortMonthsParse[i] = new RegExp(
                    '^' + this.monthsShort(mom, '').replace('.', '') + '$',
                    'i'
                );
            }
            if (!strict && !this._monthsParse[i]) {
                regex =
                    '^' + this.months(mom, '') + '|^' + this.monthsShort(mom, '');
                this._monthsParse[i] = new RegExp(regex.replace('.', ''), 'i');
            }
            // test the regex
            if (
                strict &&
                format === 'MMMM' &&
                this._longMonthsParse[i].test(monthName)
            ) {
                return i;
            } else if (
                strict &&
                format === 'MMM' &&
                this._shortMonthsParse[i].test(monthName)
            ) {
                return i;
            } else if (!strict && this._monthsParse[i].test(monthName)) {
                return i;
            }
        }
    }

    // MOMENTS

    function setMonth(mom, value) {
        var dayOfMonth;

        if (!mom.isValid()) {
            // No op
            return mom;
        }

        if (typeof value === 'string') {
            if (/^\d+$/.test(value)) {
                value = toInt(value);
            } else {
                value = mom.localeData().monthsParse(value);
                // TODO: Another silent failure?
                if (!isNumber(value)) {
                    return mom;
                }
            }
        }

        dayOfMonth = Math.min(mom.date(), daysInMonth(mom.year(), value));
        mom._d['set' + (mom._isUTC ? 'UTC' : '') + 'Month'](value, dayOfMonth);
        return mom;
    }

    function getSetMonth(value) {
        if (value != null) {
            setMonth(this, value);
            hooks.updateOffset(this, true);
            return this;
        } else {
            return get(this, 'Month');
        }
    }

    function getDaysInMonth() {
        return daysInMonth(this.year(), this.month());
    }

    function monthsShortRegex(isStrict) {
        if (this._monthsParseExact) {
            if (!hasOwnProp(this, '_monthsRegex')) {
                computeMonthsParse.call(this);
            }
            if (isStrict) {
                return this._monthsShortStrictRegex;
            } else {
                return this._monthsShortRegex;
            }
        } else {
            if (!hasOwnProp(this, '_monthsShortRegex')) {
                this._monthsShortRegex = defaultMonthsShortRegex;
            }
            return this._monthsShortStrictRegex && isStrict
                ? this._monthsShortStrictRegex
                : this._monthsShortRegex;
        }
    }

    function monthsRegex(isStrict) {
        if (this._monthsParseExact) {
            if (!hasOwnProp(this, '_monthsRegex')) {
                computeMonthsParse.call(this);
            }
            if (isStrict) {
                return this._monthsStrictRegex;
            } else {
                return this._monthsRegex;
            }
        } else {
            if (!hasOwnProp(this, '_monthsRegex')) {
                this._monthsRegex = defaultMonthsRegex;
            }
            return this._monthsStrictRegex && isStrict
                ? this._monthsStrictRegex
                : this._monthsRegex;
        }
    }

    function computeMonthsParse() {
        function cmpLenRev(a, b) {
            return b.length - a.length;
        }

        var shortPieces = [],
            longPieces = [],
            mixedPieces = [],
            i,
            mom;
        for (i = 0; i < 12; i++) {
            // make the regex if we don't have it already
            mom = createUTC([2000, i]);
            shortPieces.push(this.monthsShort(mom, ''));
            longPieces.push(this.months(mom, ''));
            mixedPieces.push(this.months(mom, ''));
            mixedPieces.push(this.monthsShort(mom, ''));
        }
        // Sorting makes sure if one month (or abbr) is a prefix of another it
        // will match the longer piece.
        shortPieces.sort(cmpLenRev);
        longPieces.sort(cmpLenRev);
        mixedPieces.sort(cmpLenRev);
        for (i = 0; i < 12; i++) {
            shortPieces[i] = regexEscape(shortPieces[i]);
            longPieces[i] = regexEscape(longPieces[i]);
        }
        for (i = 0; i < 24; i++) {
            mixedPieces[i] = regexEscape(mixedPieces[i]);
        }

        this._monthsRegex = new RegExp('^(' + mixedPieces.join('|') + ')', 'i');
        this._monthsShortRegex = this._monthsRegex;
        this._monthsStrictRegex = new RegExp(
            '^(' + longPieces.join('|') + ')',
            'i'
        );
        this._monthsShortStrictRegex = new RegExp(
            '^(' + shortPieces.join('|') + ')',
            'i'
        );
    }

    // FORMATTING

    addFormatToken('Y', 0, 0, function () {
        var y = this.year();
        return y <= 9999 ? zeroFill(y, 4) : '+' + y;
    });

    addFormatToken(0, ['YY', 2], 0, function () {
        return this.year() % 100;
    });

    addFormatToken(0, ['YYYY', 4], 0, 'year');
    addFormatToken(0, ['YYYYY', 5], 0, 'year');
    addFormatToken(0, ['YYYYYY', 6, true], 0, 'year');

    // ALIASES

    addUnitAlias('year', 'y');

    // PRIORITIES

    addUnitPriority('year', 1);

    // PARSING

    addRegexToken('Y', matchSigned);
    addRegexToken('YY', match1to2, match2);
    addRegexToken('YYYY', match1to4, match4);
    addRegexToken('YYYYY', match1to6, match6);
    addRegexToken('YYYYYY', match1to6, match6);

    addParseToken(['YYYYY', 'YYYYYY'], YEAR);
    addParseToken('YYYY', function (input, array) {
        array[YEAR] =
            input.length === 2 ? hooks.parseTwoDigitYear(input) : toInt(input);
    });
    addParseToken('YY', function (input, array) {
        array[YEAR] = hooks.parseTwoDigitYear(input);
    });
    addParseToken('Y', function (input, array) {
        array[YEAR] = parseInt(input, 10);
    });

    // HELPERS

    function daysInYear(year) {
        return isLeapYear(year) ? 366 : 365;
    }

    // HOOKS

    hooks.parseTwoDigitYear = function (input) {
        return toInt(input) + (toInt(input) > 68 ? 1900 : 2000);
    };

    // MOMENTS

    var getSetYear = makeGetSet('FullYear', true);

    function getIsLeapYear() {
        return isLeapYear(this.year());
    }

    function createDate(y, m, d, h, M, s, ms) {
        // can't just apply() to create a date:
        // https://stackoverflow.com/q/181348
        var date;
        // the date constructor remaps years 0-99 to 1900-1999
        if (y < 100 && y >= 0) {
            // preserve leap years using a full 400 year cycle, then reset
            date = new Date(y + 400, m, d, h, M, s, ms);
            if (isFinite(date.getFullYear())) {
                date.setFullYear(y);
            }
        } else {
            date = new Date(y, m, d, h, M, s, ms);
        }

        return date;
    }

    function createUTCDate(y) {
        var date, args;
        // the Date.UTC function remaps years 0-99 to 1900-1999
        if (y < 100 && y >= 0) {
            args = Array.prototype.slice.call(arguments);
            // preserve leap years using a full 400 year cycle, then reset
            args[0] = y + 400;
            date = new Date(Date.UTC.apply(null, args));
            if (isFinite(date.getUTCFullYear())) {
                date.setUTCFullYear(y);
            }
        } else {
            date = new Date(Date.UTC.apply(null, arguments));
        }

        return date;
    }

    // start-of-first-week - start-of-year
    function firstWeekOffset(year, dow, doy) {
        var // first-week day -- which january is always in the first week (4 for iso, 1 for other)
            fwd = 7 + dow - doy,
            // first-week day local weekday -- which local weekday is fwd
            fwdlw = (7 + createUTCDate(year, 0, fwd).getUTCDay() - dow) % 7;

        return -fwdlw + fwd - 1;
    }

    // https://en.wikipedia.org/wiki/ISO_week_date#Calculating_a_date_given_the_year.2C_week_number_and_weekday
    function dayOfYearFromWeeks(year, week, weekday, dow, doy) {
        var localWeekday = (7 + weekday - dow) % 7,
            weekOffset = firstWeekOffset(year, dow, doy),
            dayOfYear = 1 + 7 * (week - 1) + localWeekday + weekOffset,
            resYear,
            resDayOfYear;

        if (dayOfYear <= 0) {
            resYear = year - 1;
            resDayOfYear = daysInYear(resYear) + dayOfYear;
        } else if (dayOfYear > daysInYear(year)) {
            resYear = year + 1;
            resDayOfYear = dayOfYear - daysInYear(year);
        } else {
            resYear = year;
            resDayOfYear = dayOfYear;
        }

        return {
            year: resYear,
            dayOfYear: resDayOfYear,
        };
    }

    function weekOfYear(mom, dow, doy) {
        var weekOffset = firstWeekOffset(mom.year(), dow, doy),
            week = Math.floor((mom.dayOfYear() - weekOffset - 1) / 7) + 1,
            resWeek,
            resYear;

        if (week < 1) {
            resYear = mom.year() - 1;
            resWeek = week + weeksInYear(resYear, dow, doy);
        } else if (week > weeksInYear(mom.year(), dow, doy)) {
            resWeek = week - weeksInYear(mom.year(), dow, doy);
            resYear = mom.year() + 1;
        } else {
            resYear = mom.year();
            resWeek = week;
        }

        return {
            week: resWeek,
            year: resYear,
        };
    }

    function weeksInYear(year, dow, doy) {
        var weekOffset = firstWeekOffset(year, dow, doy),
            weekOffsetNext = firstWeekOffset(year + 1, dow, doy);
        return (daysInYear(year) - weekOffset + weekOffsetNext) / 7;
    }

    // FORMATTING

    addFormatToken('w', ['ww', 2], 'wo', 'week');
    addFormatToken('W', ['WW', 2], 'Wo', 'isoWeek');

    // ALIASES

    addUnitAlias('week', 'w');
    addUnitAlias('isoWeek', 'W');

    // PRIORITIES

    addUnitPriority('week', 5);
    addUnitPriority('isoWeek', 5);

    // PARSING

    addRegexToken('w', match1to2);
    addRegexToken('ww', match1to2, match2);
    addRegexToken('W', match1to2);
    addRegexToken('WW', match1to2, match2);

    addWeekParseToken(['w', 'ww', 'W', 'WW'], function (
        input,
        week,
        config,
        token
    ) {
        week[token.substr(0, 1)] = toInt(input);
    });

    // HELPERS

    // LOCALES

    function localeWeek(mom) {
        return weekOfYear(mom, this._week.dow, this._week.doy).week;
    }

    var defaultLocaleWeek = {
        dow: 0, // Sunday is the first day of the week.
        doy: 6, // The week that contains Jan 6th is the first week of the year.
    };

    function localeFirstDayOfWeek() {
        return this._week.dow;
    }

    function localeFirstDayOfYear() {
        return this._week.doy;
    }

    // MOMENTS

    function getSetWeek(input) {
        var week = this.localeData().week(this);
        return input == null ? week : this.add((input - week) * 7, 'd');
    }

    function getSetISOWeek(input) {
        var week = weekOfYear(this, 1, 4).week;
        return input == null ? week : this.add((input - week) * 7, 'd');
    }

    // FORMATTING

    addFormatToken('d', 0, 'do', 'day');

    addFormatToken('dd', 0, 0, function (format) {
        return this.localeData().weekdaysMin(this, format);
    });

    addFormatToken('ddd', 0, 0, function (format) {
        return this.localeData().weekdaysShort(this, format);
    });

    addFormatToken('dddd', 0, 0, function (format) {
        return this.localeData().weekdays(this, format);
    });

    addFormatToken('e', 0, 0, 'weekday');
    addFormatToken('E', 0, 0, 'isoWeekday');

    // ALIASES

    addUnitAlias('day', 'd');
    addUnitAlias('weekday', 'e');
    addUnitAlias('isoWeekday', 'E');

    // PRIORITY
    addUnitPriority('day', 11);
    addUnitPriority('weekday', 11);
    addUnitPriority('isoWeekday', 11);

    // PARSING

    addRegexToken('d', match1to2);
    addRegexToken('e', match1to2);
    addRegexToken('E', match1to2);
    addRegexToken('dd', function (isStrict, locale) {
        return locale.weekdaysMinRegex(isStrict);
    });
    addRegexToken('ddd', function (isStrict, locale) {
        return locale.weekdaysShortRegex(isStrict);
    });
    addRegexToken('dddd', function (isStrict, locale) {
        return locale.weekdaysRegex(isStrict);
    });

    addWeekParseToken(['dd', 'ddd', 'dddd'], function (input, week, config, token) {
        var weekday = config._locale.weekdaysParse(input, token, config._strict);
        // if we didn't get a weekday name, mark the date as invalid
        if (weekday != null) {
            week.d = weekday;
        } else {
            getParsingFlags(config).invalidWeekday = input;
        }
    });

    addWeekParseToken(['d', 'e', 'E'], function (input, week, config, token) {
        week[token] = toInt(input);
    });

    // HELPERS

    function parseWeekday(input, locale) {
        if (typeof input !== 'string') {
            return input;
        }

        if (!isNaN(input)) {
            return parseInt(input, 10);
        }

        input = locale.weekdaysParse(input);
        if (typeof input === 'number') {
            return input;
        }

        return null;
    }

    function parseIsoWeekday(input, locale) {
        if (typeof input === 'string') {
            return locale.weekdaysParse(input) % 7 || 7;
        }
        return isNaN(input) ? null : input;
    }

    // LOCALES
    function shiftWeekdays(ws, n) {
        return ws.slice(n, 7).concat(ws.slice(0, n));
    }

    var defaultLocaleWeekdays = 'Sunday_Monday_Tuesday_Wednesday_Thursday_Friday_Saturday'.split(
            '_'
        ),
        defaultLocaleWeekdaysShort = 'Sun_Mon_Tue_Wed_Thu_Fri_Sat'.split('_'),
        defaultLocaleWeekdaysMin = 'Su_Mo_Tu_We_Th_Fr_Sa'.split('_'),
        defaultWeekdaysRegex = matchWord,
        defaultWeekdaysShortRegex = matchWord,
        defaultWeekdaysMinRegex = matchWord;

    function localeWeekdays(m, format) {
        var weekdays = isArray(this._weekdays)
            ? this._weekdays
            : this._weekdays[
                  m && m !== true && this._weekdays.isFormat.test(format)
                      ? 'format'
                      : 'standalone'
              ];
        return m === true
            ? shiftWeekdays(weekdays, this._week.dow)
            : m
            ? weekdays[m.day()]
            : weekdays;
    }

    function localeWeekdaysShort(m) {
        return m === true
            ? shiftWeekdays(this._weekdaysShort, this._week.dow)
            : m
            ? this._weekdaysShort[m.day()]
            : this._weekdaysShort;
    }

    function localeWeekdaysMin(m) {
        return m === true
            ? shiftWeekdays(this._weekdaysMin, this._week.dow)
            : m
            ? this._weekdaysMin[m.day()]
            : this._weekdaysMin;
    }

    function handleStrictParse$1(weekdayName, format, strict) {
        var i,
            ii,
            mom,
            llc = weekdayName.toLocaleLowerCase();
        if (!this._weekdaysParse) {
            this._weekdaysParse = [];
            this._shortWeekdaysParse = [];
            this._minWeekdaysParse = [];

            for (i = 0; i < 7; ++i) {
                mom = createUTC([2000, 1]).day(i);
                this._minWeekdaysParse[i] = this.weekdaysMin(
                    mom,
                    ''
                ).toLocaleLowerCase();
                this._shortWeekdaysParse[i] = this.weekdaysShort(
                    mom,
                    ''
                ).toLocaleLowerCase();
                this._weekdaysParse[i] = this.weekdays(mom, '').toLocaleLowerCase();
            }
        }

        if (strict) {
            if (format === 'dddd') {
                ii = indexOf.call(this._weekdaysParse, llc);
                return ii !== -1 ? ii : null;
            } else if (format === 'ddd') {
                ii = indexOf.call(this._shortWeekdaysParse, llc);
                return ii !== -1 ? ii : null;
            } else {
                ii = indexOf.call(this._minWeekdaysParse, llc);
                return ii !== -1 ? ii : null;
            }
        } else {
            if (format === 'dddd') {
                ii = indexOf.call(this._weekdaysParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._shortWeekdaysParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._minWeekdaysParse, llc);
                return ii !== -1 ? ii : null;
            } else if (format === 'ddd') {
                ii = indexOf.call(this._shortWeekdaysParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._weekdaysParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._minWeekdaysParse, llc);
                return ii !== -1 ? ii : null;
            } else {
                ii = indexOf.call(this._minWeekdaysParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._weekdaysParse, llc);
                if (ii !== -1) {
                    return ii;
                }
                ii = indexOf.call(this._shortWeekdaysParse, llc);
                return ii !== -1 ? ii : null;
            }
        }
    }

    function localeWeekdaysParse(weekdayName, format, strict) {
        var i, mom, regex;

        if (this._weekdaysParseExact) {
            return handleStrictParse$1.call(this, weekdayName, format, strict);
        }

        if (!this._weekdaysParse) {
            this._weekdaysParse = [];
            this._minWeekdaysParse = [];
            this._shortWeekdaysParse = [];
            this._fullWeekdaysParse = [];
        }

        for (i = 0; i < 7; i++) {
            // make the regex if we don't have it already

            mom = createUTC([2000, 1]).day(i);
            if (strict && !this._fullWeekdaysParse[i]) {
                this._fullWeekdaysParse[i] = new RegExp(
                    '^' + this.weekdays(mom, '').replace('.', '\\.?') + '$',
                    'i'
                );
                this._shortWeekdaysParse[i] = new RegExp(
                    '^' + this.weekdaysShort(mom, '').replace('.', '\\.?') + '$',
                    'i'
                );
                this._minWeekdaysParse[i] = new RegExp(
                    '^' + this.weekdaysMin(mom, '').replace('.', '\\.?') + '$',
                    'i'
                );
            }
            if (!this._weekdaysParse[i]) {
                regex =
                    '^' +
                    this.weekdays(mom, '') +
                    '|^' +
                    this.weekdaysShort(mom, '') +
                    '|^' +
                    this.weekdaysMin(mom, '');
                this._weekdaysParse[i] = new RegExp(regex.replace('.', ''), 'i');
            }
            // test the regex
            if (
                strict &&
                format === 'dddd' &&
                this._fullWeekdaysParse[i].test(weekdayName)
            ) {
                return i;
            } else if (
                strict &&
                format === 'ddd' &&
                this._shortWeekdaysParse[i].test(weekdayName)
            ) {
                return i;
            } else if (
                strict &&
                format === 'dd' &&
                this._minWeekdaysParse[i].test(weekdayName)
            ) {
                return i;
            } else if (!strict && this._weekdaysParse[i].test(weekdayName)) {
                return i;
            }
        }
    }

    // MOMENTS

    function getSetDayOfWeek(input) {
        if (!this.isValid()) {
            return input != null ? this : NaN;
        }
        var day = this._isUTC ? this._d.getUTCDay() : this._d.getDay();
        if (input != null) {
            input = parseWeekday(input, this.localeData());
            return this.add(input - day, 'd');
        } else {
            return day;
        }
    }

    function getSetLocaleDayOfWeek(input) {
        if (!this.isValid()) {
            return input != null ? this : NaN;
        }
        var weekday = (this.day() + 7 - this.localeData()._week.dow) % 7;
        return input == null ? weekday : this.add(input - weekday, 'd');
    }

    function getSetISODayOfWeek(input) {
        if (!this.isValid()) {
            return input != null ? this : NaN;
        }

        // behaves the same as moment#day except
        // as a getter, returns 7 instead of 0 (1-7 range instead of 0-6)
        // as a setter, sunday should belong to the previous week.

        if (input != null) {
            var weekday = parseIsoWeekday(input, this.localeData());
            return this.day(this.day() % 7 ? weekday : weekday - 7);
        } else {
            return this.day() || 7;
        }
    }

    function weekdaysRegex(isStrict) {
        if (this._weekdaysParseExact) {
            if (!hasOwnProp(this, '_weekdaysRegex')) {
                computeWeekdaysParse.call(this);
            }
            if (isStrict) {
                return this._weekdaysStrictRegex;
            } else {
                return this._weekdaysRegex;
            }
        } else {
            if (!hasOwnProp(this, '_weekdaysRegex')) {
                this._weekdaysRegex = defaultWeekdaysRegex;
            }
            return this._weekdaysStrictRegex && isStrict
                ? this._weekdaysStrictRegex
                : this._weekdaysRegex;
        }
    }

    function weekdaysShortRegex(isStrict) {
        if (this._weekdaysParseExact) {
            if (!hasOwnProp(this, '_weekdaysRegex')) {
                computeWeekdaysParse.call(this);
            }
            if (isStrict) {
                return this._weekdaysShortStrictRegex;
            } else {
                return this._weekdaysShortRegex;
            }
        } else {
            if (!hasOwnProp(this, '_weekdaysShortRegex')) {
                this._weekdaysShortRegex = defaultWeekdaysShortRegex;
            }
            return this._weekdaysShortStrictRegex && isStrict
                ? this._weekdaysShortStrictRegex
                : this._weekdaysShortRegex;
        }
    }

    function weekdaysMinRegex(isStrict) {
        if (this._weekdaysParseExact) {
            if (!hasOwnProp(this, '_weekdaysRegex')) {
                computeWeekdaysParse.call(this);
            }
            if (isStrict) {
                return this._weekdaysMinStrictRegex;
            } else {
                return this._weekdaysMinRegex;
            }
        } else {
            if (!hasOwnProp(this, '_weekdaysMinRegex')) {
                this._weekdaysMinRegex = defaultWeekdaysMinRegex;
            }
            return this._weekdaysMinStrictRegex && isStrict
                ? this._weekdaysMinStrictRegex
                : this._weekdaysMinRegex;
        }
    }

    function computeWeekdaysParse() {
        function cmpLenRev(a, b) {
            return b.length - a.length;
        }

        var minPieces = [],
            shortPieces = [],
            longPieces = [],
            mixedPieces = [],
            i,
            mom,
            minp,
            shortp,
            longp;
        for (i = 0; i < 7; i++) {
            // make the regex if we don't have it already
            mom = createUTC([2000, 1]).day(i);
            minp = regexEscape(this.weekdaysMin(mom, ''));
            shortp = regexEscape(this.weekdaysShort(mom, ''));
            longp = regexEscape(this.weekdays(mom, ''));
            minPieces.push(minp);
            shortPieces.push(shortp);
            longPieces.push(longp);
            mixedPieces.push(minp);
            mixedPieces.push(shortp);
            mixedPieces.push(longp);
        }
        // Sorting makes sure if one weekday (or abbr) is a prefix of another it
        // will match the longer piece.
        minPieces.sort(cmpLenRev);
        shortPieces.sort(cmpLenRev);
        longPieces.sort(cmpLenRev);
        mixedPieces.sort(cmpLenRev);

        this._weekdaysRegex = new RegExp('^(' + mixedPieces.join('|') + ')', 'i');
        this._weekdaysShortRegex = this._weekdaysRegex;
        this._weekdaysMinRegex = this._weekdaysRegex;

        this._weekdaysStrictRegex = new RegExp(
            '^(' + longPieces.join('|') + ')',
            'i'
        );
        this._weekdaysShortStrictRegex = new RegExp(
            '^(' + shortPieces.join('|') + ')',
            'i'
        );
        this._weekdaysMinStrictRegex = new RegExp(
            '^(' + minPieces.join('|') + ')',
            'i'
        );
    }

    // FORMATTING

    function hFormat() {
        return this.hours() % 12 || 12;
    }

    function kFormat() {
        return this.hours() || 24;
    }

    addFormatToken('H', ['HH', 2], 0, 'hour');
    addFormatToken('h', ['hh', 2], 0, hFormat);
    addFormatToken('k', ['kk', 2], 0, kFormat);

    addFormatToken('hmm', 0, 0, function () {
        return '' + hFormat.apply(this) + zeroFill(this.minutes(), 2);
    });

    addFormatToken('hmmss', 0, 0, function () {
        return (
            '' +
            hFormat.apply(this) +
            zeroFill(this.minutes(), 2) +
            zeroFill(this.seconds(), 2)
        );
    });

    addFormatToken('Hmm', 0, 0, function () {
        return '' + this.hours() + zeroFill(this.minutes(), 2);
    });

    addFormatToken('Hmmss', 0, 0, function () {
        return (
            '' +
            this.hours() +
            zeroFill(this.minutes(), 2) +
            zeroFill(this.seconds(), 2)
        );
    });

    function meridiem(token, lowercase) {
        addFormatToken(token, 0, 0, function () {
            return this.localeData().meridiem(
                this.hours(),
                this.minutes(),
                lowercase
            );
        });
    }

    meridiem('a', true);
    meridiem('A', false);

    // ALIASES

    addUnitAlias('hour', 'h');

    // PRIORITY
    addUnitPriority('hour', 13);

    // PARSING

    function matchMeridiem(isStrict, locale) {
        return locale._meridiemParse;
    }

    addRegexToken('a', matchMeridiem);
    addRegexToken('A', matchMeridiem);
    addRegexToken('H', match1to2);
    addRegexToken('h', match1to2);
    addRegexToken('k', match1to2);
    addRegexToken('HH', match1to2, match2);
    addRegexToken('hh', match1to2, match2);
    addRegexToken('kk', match1to2, match2);

    addRegexToken('hmm', match3to4);
    addRegexToken('hmmss', match5to6);
    addRegexToken('Hmm', match3to4);
    addRegexToken('Hmmss', match5to6);

    addParseToken(['H', 'HH'], HOUR);
    addParseToken(['k', 'kk'], function (input, array, config) {
        var kInput = toInt(input);
        array[HOUR] = kInput === 24 ? 0 : kInput;
    });
    addParseToken(['a', 'A'], function (input, array, config) {
        config._isPm = config._locale.isPM(input);
        config._meridiem = input;
    });
    addParseToken(['h', 'hh'], function (input, array, config) {
        array[HOUR] = toInt(input);
        getParsingFlags(config).bigHour = true;
    });
    addParseToken('hmm', function (input, array, config) {
        var pos = input.length - 2;
        array[HOUR] = toInt(input.substr(0, pos));
        array[MINUTE] = toInt(input.substr(pos));
        getParsingFlags(config).bigHour = true;
    });
    addParseToken('hmmss', function (input, array, config) {
        var pos1 = input.length - 4,
            pos2 = input.length - 2;
        array[HOUR] = toInt(input.substr(0, pos1));
        array[MINUTE] = toInt(input.substr(pos1, 2));
        array[SECOND] = toInt(input.substr(pos2));
        getParsingFlags(config).bigHour = true;
    });
    addParseToken('Hmm', function (input, array, config) {
        var pos = input.length - 2;
        array[HOUR] = toInt(input.substr(0, pos));
        array[MINUTE] = toInt(input.substr(pos));
    });
    addParseToken('Hmmss', function (input, array, config) {
        var pos1 = input.length - 4,
            pos2 = input.length - 2;
        array[HOUR] = toInt(input.substr(0, pos1));
        array[MINUTE] = toInt(input.substr(pos1, 2));
        array[SECOND] = toInt(input.substr(pos2));
    });

    // LOCALES

    function localeIsPM(input) {
        // IE8 Quirks Mode & IE7 Standards Mode do not allow accessing strings like arrays
        // Using charAt should be more compatible.
        return (input + '').toLowerCase().charAt(0) === 'p';
    }

    var defaultLocaleMeridiemParse = /[ap]\.?m?\.?/i,
        // Setting the hour should keep the time, because the user explicitly
        // specified which hour they want. So trying to maintain the same hour (in
        // a new timezone) makes sense. Adding/subtracting hours does not follow
        // this rule.
        getSetHour = makeGetSet('Hours', true);

    function localeMeridiem(hours, minutes, isLower) {
        if (hours > 11) {
            return isLower ? 'pm' : 'PM';
        } else {
            return isLower ? 'am' : 'AM';
        }
    }

    var baseConfig = {
        calendar: defaultCalendar,
        longDateFormat: defaultLongDateFormat,
        invalidDate: defaultInvalidDate,
        ordinal: defaultOrdinal,
        dayOfMonthOrdinalParse: defaultDayOfMonthOrdinalParse,
        relativeTime: defaultRelativeTime,

        months: defaultLocaleMonths,
        monthsShort: defaultLocaleMonthsShort,

        week: defaultLocaleWeek,

        weekdays: defaultLocaleWeekdays,
        weekdaysMin: defaultLocaleWeekdaysMin,
        weekdaysShort: defaultLocaleWeekdaysShort,

        meridiemParse: defaultLocaleMeridiemParse,
    };

    // internal storage for locale config files
    var locales = {},
        localeFamilies = {},
        globalLocale;

    function commonPrefix(arr1, arr2) {
        var i,
            minl = Math.min(arr1.length, arr2.length);
        for (i = 0; i < minl; i += 1) {
            if (arr1[i] !== arr2[i]) {
                return i;
            }
        }
        return minl;
    }

    function normalizeLocale(key) {
        return key ? key.toLowerCase().replace('_', '-') : key;
    }

    // pick the locale from the array
    // try ['en-au', 'en-gb'] as 'en-au', 'en-gb', 'en', as in move through the list trying each
    // substring from most specific to least, but move to the next array item if it's a more specific variant than the current root
    function chooseLocale(names) {
        var i = 0,
            j,
            next,
            locale,
            split;

        while (i < names.length) {
            split = normalizeLocale(names[i]).split('-');
            j = split.length;
            next = normalizeLocale(names[i + 1]);
            next = next ? next.split('-') : null;
            while (j > 0) {
                locale = loadLocale(split.slice(0, j).join('-'));
                if (locale) {
                    return locale;
                }
                if (
                    next &&
                    next.length >= j &&
                    commonPrefix(split, next) >= j - 1
                ) {
                    //the next array item is better than a shallower substring of this one
                    break;
                }
                j--;
            }
            i++;
        }
        return globalLocale;
    }

    function loadLocale(name) {
        var oldLocale = null,
            aliasedRequire;
        // TODO: Find a better way to register and load all the locales in Node
        if (
            locales[name] === undefined &&
            'object' !== 'undefined' &&
            module &&
            module.exports
        ) {
            try {
                oldLocale = globalLocale._abbr;
                aliasedRequire = commonjsRequire;
                aliasedRequire('./locale/' + name);
                getSetGlobalLocale(oldLocale);
            } catch (e) {
                // mark as not found to avoid repeating expensive file require call causing high CPU
                // when trying to find en-US, en_US, en-us for every format call
                locales[name] = null; // null means not found
            }
        }
        return locales[name];
    }

    // This function will load locale and then set the global locale.  If
    // no arguments are passed in, it will simply return the current global
    // locale key.
    function getSetGlobalLocale(key, values) {
        var data;
        if (key) {
            if (isUndefined(values)) {
                data = getLocale(key);
            } else {
                data = defineLocale(key, values);
            }

            if (data) {
                // moment.duration._locale = moment._locale = data;
                globalLocale = data;
            } else {
                if (typeof console !== 'undefined' && console.warn) {
                    //warn user if arguments are passed but the locale could not be set
                    console.warn(
                        'Locale ' + key + ' not found. Did you forget to load it?'
                    );
                }
            }
        }

        return globalLocale._abbr;
    }

    function defineLocale(name, config) {
        if (config !== null) {
            var locale,
                parentConfig = baseConfig;
            config.abbr = name;
            if (locales[name] != null) {
                deprecateSimple(
                    'defineLocaleOverride',
                    'use moment.updateLocale(localeName, config) to change ' +
                        'an existing locale. moment.defineLocale(localeName, ' +
                        'config) should only be used for creating a new locale ' +
                        'See http://momentjs.com/guides/#/warnings/define-locale/ for more info.'
                );
                parentConfig = locales[name]._config;
            } else if (config.parentLocale != null) {
                if (locales[config.parentLocale] != null) {
                    parentConfig = locales[config.parentLocale]._config;
                } else {
                    locale = loadLocale(config.parentLocale);
                    if (locale != null) {
                        parentConfig = locale._config;
                    } else {
                        if (!localeFamilies[config.parentLocale]) {
                            localeFamilies[config.parentLocale] = [];
                        }
                        localeFamilies[config.parentLocale].push({
                            name: name,
                            config: config,
                        });
                        return null;
                    }
                }
            }
            locales[name] = new Locale(mergeConfigs(parentConfig, config));

            if (localeFamilies[name]) {
                localeFamilies[name].forEach(function (x) {
                    defineLocale(x.name, x.config);
                });
            }

            // backwards compat for now: also set the locale
            // make sure we set the locale AFTER all child locales have been
            // created, so we won't end up with the child locale set.
            getSetGlobalLocale(name);

            return locales[name];
        } else {
            // useful for testing
            delete locales[name];
            return null;
        }
    }

    function updateLocale(name, config) {
        if (config != null) {
            var locale,
                tmpLocale,
                parentConfig = baseConfig;

            if (locales[name] != null && locales[name].parentLocale != null) {
                // Update existing child locale in-place to avoid memory-leaks
                locales[name].set(mergeConfigs(locales[name]._config, config));
            } else {
                // MERGE
                tmpLocale = loadLocale(name);
                if (tmpLocale != null) {
                    parentConfig = tmpLocale._config;
                }
                config = mergeConfigs(parentConfig, config);
                if (tmpLocale == null) {
                    // updateLocale is called for creating a new locale
                    // Set abbr so it will have a name (getters return
                    // undefined otherwise).
                    config.abbr = name;
                }
                locale = new Locale(config);
                locale.parentLocale = locales[name];
                locales[name] = locale;
            }

            // backwards compat for now: also set the locale
            getSetGlobalLocale(name);
        } else {
            // pass null for config to unupdate, useful for tests
            if (locales[name] != null) {
                if (locales[name].parentLocale != null) {
                    locales[name] = locales[name].parentLocale;
                    if (name === getSetGlobalLocale()) {
                        getSetGlobalLocale(name);
                    }
                } else if (locales[name] != null) {
                    delete locales[name];
                }
            }
        }
        return locales[name];
    }

    // returns locale data
    function getLocale(key) {
        var locale;

        if (key && key._locale && key._locale._abbr) {
            key = key._locale._abbr;
        }

        if (!key) {
            return globalLocale;
        }

        if (!isArray(key)) {
            //short-circuit everything else
            locale = loadLocale(key);
            if (locale) {
                return locale;
            }
            key = [key];
        }

        return chooseLocale(key);
    }

    function listLocales() {
        return keys(locales);
    }

    function checkOverflow(m) {
        var overflow,
            a = m._a;

        if (a && getParsingFlags(m).overflow === -2) {
            overflow =
                a[MONTH] < 0 || a[MONTH] > 11
                    ? MONTH
                    : a[DATE] < 1 || a[DATE] > daysInMonth(a[YEAR], a[MONTH])
                    ? DATE
                    : a[HOUR] < 0 ||
                      a[HOUR] > 24 ||
                      (a[HOUR] === 24 &&
                          (a[MINUTE] !== 0 ||
                              a[SECOND] !== 0 ||
                              a[MILLISECOND] !== 0))
                    ? HOUR
                    : a[MINUTE] < 0 || a[MINUTE] > 59
                    ? MINUTE
                    : a[SECOND] < 0 || a[SECOND] > 59
                    ? SECOND
                    : a[MILLISECOND] < 0 || a[MILLISECOND] > 999
                    ? MILLISECOND
                    : -1;

            if (
                getParsingFlags(m)._overflowDayOfYear &&
                (overflow < YEAR || overflow > DATE)
            ) {
                overflow = DATE;
            }
            if (getParsingFlags(m)._overflowWeeks && overflow === -1) {
                overflow = WEEK;
            }
            if (getParsingFlags(m)._overflowWeekday && overflow === -1) {
                overflow = WEEKDAY;
            }

            getParsingFlags(m).overflow = overflow;
        }

        return m;
    }

    // iso 8601 regex
    // 0000-00-00 0000-W00 or 0000-W00-0 + T + 00 or 00:00 or 00:00:00 or 00:00:00.000 + +00:00 or +0000 or +00)
    var extendedIsoRegex = /^\s*((?:[+-]\d{6}|\d{4})-(?:\d\d-\d\d|W\d\d-\d|W\d\d|\d\d\d|\d\d))(?:(T| )(\d\d(?::\d\d(?::\d\d(?:[.,]\d+)?)?)?)([+-]\d\d(?::?\d\d)?|\s*Z)?)?$/,
        basicIsoRegex = /^\s*((?:[+-]\d{6}|\d{4})(?:\d\d\d\d|W\d\d\d|W\d\d|\d\d\d|\d\d|))(?:(T| )(\d\d(?:\d\d(?:\d\d(?:[.,]\d+)?)?)?)([+-]\d\d(?::?\d\d)?|\s*Z)?)?$/,
        tzRegex = /Z|[+-]\d\d(?::?\d\d)?/,
        isoDates = [
            ['YYYYYY-MM-DD', /[+-]\d{6}-\d\d-\d\d/],
            ['YYYY-MM-DD', /\d{4}-\d\d-\d\d/],
            ['GGGG-[W]WW-E', /\d{4}-W\d\d-\d/],
            ['GGGG-[W]WW', /\d{4}-W\d\d/, false],
            ['YYYY-DDD', /\d{4}-\d{3}/],
            ['YYYY-MM', /\d{4}-\d\d/, false],
            ['YYYYYYMMDD', /[+-]\d{10}/],
            ['YYYYMMDD', /\d{8}/],
            ['GGGG[W]WWE', /\d{4}W\d{3}/],
            ['GGGG[W]WW', /\d{4}W\d{2}/, false],
            ['YYYYDDD', /\d{7}/],
            ['YYYYMM', /\d{6}/, false],
            ['YYYY', /\d{4}/, false],
        ],
        // iso time formats and regexes
        isoTimes = [
            ['HH:mm:ss.SSSS', /\d\d:\d\d:\d\d\.\d+/],
            ['HH:mm:ss,SSSS', /\d\d:\d\d:\d\d,\d+/],
            ['HH:mm:ss', /\d\d:\d\d:\d\d/],
            ['HH:mm', /\d\d:\d\d/],
            ['HHmmss.SSSS', /\d\d\d\d\d\d\.\d+/],
            ['HHmmss,SSSS', /\d\d\d\d\d\d,\d+/],
            ['HHmmss', /\d\d\d\d\d\d/],
            ['HHmm', /\d\d\d\d/],
            ['HH', /\d\d/],
        ],
        aspNetJsonRegex = /^\/?Date\((-?\d+)/i,
        // RFC 2822 regex: For details see https://tools.ietf.org/html/rfc2822#section-3.3
        rfc2822 = /^(?:(Mon|Tue|Wed|Thu|Fri|Sat|Sun),?\s)?(\d{1,2})\s(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\s(\d{2,4})\s(\d\d):(\d\d)(?::(\d\d))?\s(?:(UT|GMT|[ECMP][SD]T)|([Zz])|([+-]\d{4}))$/,
        obsOffsets = {
            UT: 0,
            GMT: 0,
            EDT: -4 * 60,
            EST: -5 * 60,
            CDT: -5 * 60,
            CST: -6 * 60,
            MDT: -6 * 60,
            MST: -7 * 60,
            PDT: -7 * 60,
            PST: -8 * 60,
        };

    // date from iso format
    function configFromISO(config) {
        var i,
            l,
            string = config._i,
            match = extendedIsoRegex.exec(string) || basicIsoRegex.exec(string),
            allowTime,
            dateFormat,
            timeFormat,
            tzFormat;

        if (match) {
            getParsingFlags(config).iso = true;

            for (i = 0, l = isoDates.length; i < l; i++) {
                if (isoDates[i][1].exec(match[1])) {
                    dateFormat = isoDates[i][0];
                    allowTime = isoDates[i][2] !== false;
                    break;
                }
            }
            if (dateFormat == null) {
                config._isValid = false;
                return;
            }
            if (match[3]) {
                for (i = 0, l = isoTimes.length; i < l; i++) {
                    if (isoTimes[i][1].exec(match[3])) {
                        // match[2] should be 'T' or space
                        timeFormat = (match[2] || ' ') + isoTimes[i][0];
                        break;
                    }
                }
                if (timeFormat == null) {
                    config._isValid = false;
                    return;
                }
            }
            if (!allowTime && timeFormat != null) {
                config._isValid = false;
                return;
            }
            if (match[4]) {
                if (tzRegex.exec(match[4])) {
                    tzFormat = 'Z';
                } else {
                    config._isValid = false;
                    return;
                }
            }
            config._f = dateFormat + (timeFormat || '') + (tzFormat || '');
            configFromStringAndFormat(config);
        } else {
            config._isValid = false;
        }
    }

    function extractFromRFC2822Strings(
        yearStr,
        monthStr,
        dayStr,
        hourStr,
        minuteStr,
        secondStr
    ) {
        var result = [
            untruncateYear(yearStr),
            defaultLocaleMonthsShort.indexOf(monthStr),
            parseInt(dayStr, 10),
            parseInt(hourStr, 10),
            parseInt(minuteStr, 10),
        ];

        if (secondStr) {
            result.push(parseInt(secondStr, 10));
        }

        return result;
    }

    function untruncateYear(yearStr) {
        var year = parseInt(yearStr, 10);
        if (year <= 49) {
            return 2000 + year;
        } else if (year <= 999) {
            return 1900 + year;
        }
        return year;
    }

    function preprocessRFC2822(s) {
        // Remove comments and folding whitespace and replace multiple-spaces with a single space
        return s
            .replace(/\([^)]*\)|[\n\t]/g, ' ')
            .replace(/(\s\s+)/g, ' ')
            .replace(/^\s\s*/, '')
            .replace(/\s\s*$/, '');
    }

    function checkWeekday(weekdayStr, parsedInput, config) {
        if (weekdayStr) {
            // TODO: Replace the vanilla JS Date object with an independent day-of-week check.
            var weekdayProvided = defaultLocaleWeekdaysShort.indexOf(weekdayStr),
                weekdayActual = new Date(
                    parsedInput[0],
                    parsedInput[1],
                    parsedInput[2]
                ).getDay();
            if (weekdayProvided !== weekdayActual) {
                getParsingFlags(config).weekdayMismatch = true;
                config._isValid = false;
                return false;
            }
        }
        return true;
    }

    function calculateOffset(obsOffset, militaryOffset, numOffset) {
        if (obsOffset) {
            return obsOffsets[obsOffset];
        } else if (militaryOffset) {
            // the only allowed military tz is Z
            return 0;
        } else {
            var hm = parseInt(numOffset, 10),
                m = hm % 100,
                h = (hm - m) / 100;
            return h * 60 + m;
        }
    }

    // date and time from ref 2822 format
    function configFromRFC2822(config) {
        var match = rfc2822.exec(preprocessRFC2822(config._i)),
            parsedArray;
        if (match) {
            parsedArray = extractFromRFC2822Strings(
                match[4],
                match[3],
                match[2],
                match[5],
                match[6],
                match[7]
            );
            if (!checkWeekday(match[1], parsedArray, config)) {
                return;
            }

            config._a = parsedArray;
            config._tzm = calculateOffset(match[8], match[9], match[10]);

            config._d = createUTCDate.apply(null, config._a);
            config._d.setUTCMinutes(config._d.getUTCMinutes() - config._tzm);

            getParsingFlags(config).rfc2822 = true;
        } else {
            config._isValid = false;
        }
    }

    // date from 1) ASP.NET, 2) ISO, 3) RFC 2822 formats, or 4) optional fallback if parsing isn't strict
    function configFromString(config) {
        var matched = aspNetJsonRegex.exec(config._i);
        if (matched !== null) {
            config._d = new Date(+matched[1]);
            return;
        }

        configFromISO(config);
        if (config._isValid === false) {
            delete config._isValid;
        } else {
            return;
        }

        configFromRFC2822(config);
        if (config._isValid === false) {
            delete config._isValid;
        } else {
            return;
        }

        if (config._strict) {
            config._isValid = false;
        } else {
            // Final attempt, use Input Fallback
            hooks.createFromInputFallback(config);
        }
    }

    hooks.createFromInputFallback = deprecate(
        'value provided is not in a recognized RFC2822 or ISO format. moment construction falls back to js Date(), ' +
            'which is not reliable across all browsers and versions. Non RFC2822/ISO date formats are ' +
            'discouraged. Please refer to http://momentjs.com/guides/#/warnings/js-date/ for more info.',
        function (config) {
            config._d = new Date(config._i + (config._useUTC ? ' UTC' : ''));
        }
    );

    // Pick the first defined of two or three arguments.
    function defaults(a, b, c) {
        if (a != null) {
            return a;
        }
        if (b != null) {
            return b;
        }
        return c;
    }

    function currentDateArray(config) {
        // hooks is actually the exported moment object
        var nowValue = new Date(hooks.now());
        if (config._useUTC) {
            return [
                nowValue.getUTCFullYear(),
                nowValue.getUTCMonth(),
                nowValue.getUTCDate(),
            ];
        }
        return [nowValue.getFullYear(), nowValue.getMonth(), nowValue.getDate()];
    }

    // convert an array to a date.
    // the array should mirror the parameters below
    // note: all values past the year are optional and will default to the lowest possible value.
    // [year, month, day , hour, minute, second, millisecond]
    function configFromArray(config) {
        var i,
            date,
            input = [],
            currentDate,
            expectedWeekday,
            yearToUse;

        if (config._d) {
            return;
        }

        currentDate = currentDateArray(config);

        //compute day of the year from weeks and weekdays
        if (config._w && config._a[DATE] == null && config._a[MONTH] == null) {
            dayOfYearFromWeekInfo(config);
        }

        //if the day of the year is set, figure out what it is
        if (config._dayOfYear != null) {
            yearToUse = defaults(config._a[YEAR], currentDate[YEAR]);

            if (
                config._dayOfYear > daysInYear(yearToUse) ||
                config._dayOfYear === 0
            ) {
                getParsingFlags(config)._overflowDayOfYear = true;
            }

            date = createUTCDate(yearToUse, 0, config._dayOfYear);
            config._a[MONTH] = date.getUTCMonth();
            config._a[DATE] = date.getUTCDate();
        }

        // Default to current date.
        // * if no year, month, day of month are given, default to today
        // * if day of month is given, default month and year
        // * if month is given, default only year
        // * if year is given, don't default anything
        for (i = 0; i < 3 && config._a[i] == null; ++i) {
            config._a[i] = input[i] = currentDate[i];
        }

        // Zero out whatever was not defaulted, including time
        for (; i < 7; i++) {
            config._a[i] = input[i] =
                config._a[i] == null ? (i === 2 ? 1 : 0) : config._a[i];
        }

        // Check for 24:00:00.000
        if (
            config._a[HOUR] === 24 &&
            config._a[MINUTE] === 0 &&
            config._a[SECOND] === 0 &&
            config._a[MILLISECOND] === 0
        ) {
            config._nextDay = true;
            config._a[HOUR] = 0;
        }

        config._d = (config._useUTC ? createUTCDate : createDate).apply(
            null,
            input
        );
        expectedWeekday = config._useUTC
            ? config._d.getUTCDay()
            : config._d.getDay();

        // Apply timezone offset from input. The actual utcOffset can be changed
        // with parseZone.
        if (config._tzm != null) {
            config._d.setUTCMinutes(config._d.getUTCMinutes() - config._tzm);
        }

        if (config._nextDay) {
            config._a[HOUR] = 24;
        }

        // check for mismatching day of week
        if (
            config._w &&
            typeof config._w.d !== 'undefined' &&
            config._w.d !== expectedWeekday
        ) {
            getParsingFlags(config).weekdayMismatch = true;
        }
    }

    function dayOfYearFromWeekInfo(config) {
        var w, weekYear, week, weekday, dow, doy, temp, weekdayOverflow, curWeek;

        w = config._w;
        if (w.GG != null || w.W != null || w.E != null) {
            dow = 1;
            doy = 4;

            // TODO: We need to take the current isoWeekYear, but that depends on
            // how we interpret now (local, utc, fixed offset). So create
            // a now version of current config (take local/utc/offset flags, and
            // create now).
            weekYear = defaults(
                w.GG,
                config._a[YEAR],
                weekOfYear(createLocal(), 1, 4).year
            );
            week = defaults(w.W, 1);
            weekday = defaults(w.E, 1);
            if (weekday < 1 || weekday > 7) {
                weekdayOverflow = true;
            }
        } else {
            dow = config._locale._week.dow;
            doy = config._locale._week.doy;

            curWeek = weekOfYear(createLocal(), dow, doy);

            weekYear = defaults(w.gg, config._a[YEAR], curWeek.year);

            // Default to current week.
            week = defaults(w.w, curWeek.week);

            if (w.d != null) {
                // weekday -- low day numbers are considered next week
                weekday = w.d;
                if (weekday < 0 || weekday > 6) {
                    weekdayOverflow = true;
                }
            } else if (w.e != null) {
                // local weekday -- counting starts from beginning of week
                weekday = w.e + dow;
                if (w.e < 0 || w.e > 6) {
                    weekdayOverflow = true;
                }
            } else {
                // default to beginning of week
                weekday = dow;
            }
        }
        if (week < 1 || week > weeksInYear(weekYear, dow, doy)) {
            getParsingFlags(config)._overflowWeeks = true;
        } else if (weekdayOverflow != null) {
            getParsingFlags(config)._overflowWeekday = true;
        } else {
            temp = dayOfYearFromWeeks(weekYear, week, weekday, dow, doy);
            config._a[YEAR] = temp.year;
            config._dayOfYear = temp.dayOfYear;
        }
    }

    // constant that refers to the ISO standard
    hooks.ISO_8601 = function () {};

    // constant that refers to the RFC 2822 form
    hooks.RFC_2822 = function () {};

    // date from string and format string
    function configFromStringAndFormat(config) {
        // TODO: Move this to another part of the creation flow to prevent circular deps
        if (config._f === hooks.ISO_8601) {
            configFromISO(config);
            return;
        }
        if (config._f === hooks.RFC_2822) {
            configFromRFC2822(config);
            return;
        }
        config._a = [];
        getParsingFlags(config).empty = true;

        // This array is used to make a Date, either with `new Date` or `Date.UTC`
        var string = '' + config._i,
            i,
            parsedInput,
            tokens,
            token,
            skipped,
            stringLength = string.length,
            totalParsedInputLength = 0,
            era;

        tokens =
            expandFormat(config._f, config._locale).match(formattingTokens) || [];

        for (i = 0; i < tokens.length; i++) {
            token = tokens[i];
            parsedInput = (string.match(getParseRegexForToken(token, config)) ||
                [])[0];
            if (parsedInput) {
                skipped = string.substr(0, string.indexOf(parsedInput));
                if (skipped.length > 0) {
                    getParsingFlags(config).unusedInput.push(skipped);
                }
                string = string.slice(
                    string.indexOf(parsedInput) + parsedInput.length
                );
                totalParsedInputLength += parsedInput.length;
            }
            // don't parse if it's not a known token
            if (formatTokenFunctions[token]) {
                if (parsedInput) {
                    getParsingFlags(config).empty = false;
                } else {
                    getParsingFlags(config).unusedTokens.push(token);
                }
                addTimeToArrayFromToken(token, parsedInput, config);
            } else if (config._strict && !parsedInput) {
                getParsingFlags(config).unusedTokens.push(token);
            }
        }

        // add remaining unparsed input length to the string
        getParsingFlags(config).charsLeftOver =
            stringLength - totalParsedInputLength;
        if (string.length > 0) {
            getParsingFlags(config).unusedInput.push(string);
        }

        // clear _12h flag if hour is <= 12
        if (
            config._a[HOUR] <= 12 &&
            getParsingFlags(config).bigHour === true &&
            config._a[HOUR] > 0
        ) {
            getParsingFlags(config).bigHour = undefined;
        }

        getParsingFlags(config).parsedDateParts = config._a.slice(0);
        getParsingFlags(config).meridiem = config._meridiem;
        // handle meridiem
        config._a[HOUR] = meridiemFixWrap(
            config._locale,
            config._a[HOUR],
            config._meridiem
        );

        // handle era
        era = getParsingFlags(config).era;
        if (era !== null) {
            config._a[YEAR] = config._locale.erasConvertYear(era, config._a[YEAR]);
        }

        configFromArray(config);
        checkOverflow(config);
    }

    function meridiemFixWrap(locale, hour, meridiem) {
        var isPm;

        if (meridiem == null) {
            // nothing to do
            return hour;
        }
        if (locale.meridiemHour != null) {
            return locale.meridiemHour(hour, meridiem);
        } else if (locale.isPM != null) {
            // Fallback
            isPm = locale.isPM(meridiem);
            if (isPm && hour < 12) {
                hour += 12;
            }
            if (!isPm && hour === 12) {
                hour = 0;
            }
            return hour;
        } else {
            // this is not supposed to happen
            return hour;
        }
    }

    // date from string and array of format strings
    function configFromStringAndArray(config) {
        var tempConfig,
            bestMoment,
            scoreToBeat,
            i,
            currentScore,
            validFormatFound,
            bestFormatIsValid = false;

        if (config._f.length === 0) {
            getParsingFlags(config).invalidFormat = true;
            config._d = new Date(NaN);
            return;
        }

        for (i = 0; i < config._f.length; i++) {
            currentScore = 0;
            validFormatFound = false;
            tempConfig = copyConfig({}, config);
            if (config._useUTC != null) {
                tempConfig._useUTC = config._useUTC;
            }
            tempConfig._f = config._f[i];
            configFromStringAndFormat(tempConfig);

            if (isValid(tempConfig)) {
                validFormatFound = true;
            }

            // if there is any input that was not parsed add a penalty for that format
            currentScore += getParsingFlags(tempConfig).charsLeftOver;

            //or tokens
            currentScore += getParsingFlags(tempConfig).unusedTokens.length * 10;

            getParsingFlags(tempConfig).score = currentScore;

            if (!bestFormatIsValid) {
                if (
                    scoreToBeat == null ||
                    currentScore < scoreToBeat ||
                    validFormatFound
                ) {
                    scoreToBeat = currentScore;
                    bestMoment = tempConfig;
                    if (validFormatFound) {
                        bestFormatIsValid = true;
                    }
                }
            } else {
                if (currentScore < scoreToBeat) {
                    scoreToBeat = currentScore;
                    bestMoment = tempConfig;
                }
            }
        }

        extend(config, bestMoment || tempConfig);
    }

    function configFromObject(config) {
        if (config._d) {
            return;
        }

        var i = normalizeObjectUnits(config._i),
            dayOrDate = i.day === undefined ? i.date : i.day;
        config._a = map(
            [i.year, i.month, dayOrDate, i.hour, i.minute, i.second, i.millisecond],
            function (obj) {
                return obj && parseInt(obj, 10);
            }
        );

        configFromArray(config);
    }

    function createFromConfig(config) {
        var res = new Moment(checkOverflow(prepareConfig(config)));
        if (res._nextDay) {
            // Adding is smart enough around DST
            res.add(1, 'd');
            res._nextDay = undefined;
        }

        return res;
    }

    function prepareConfig(config) {
        var input = config._i,
            format = config._f;

        config._locale = config._locale || getLocale(config._l);

        if (input === null || (format === undefined && input === '')) {
            return createInvalid({ nullInput: true });
        }

        if (typeof input === 'string') {
            config._i = input = config._locale.preparse(input);
        }

        if (isMoment(input)) {
            return new Moment(checkOverflow(input));
        } else if (isDate(input)) {
            config._d = input;
        } else if (isArray(format)) {
            configFromStringAndArray(config);
        } else if (format) {
            configFromStringAndFormat(config);
        } else {
            configFromInput(config);
        }

        if (!isValid(config)) {
            config._d = null;
        }

        return config;
    }

    function configFromInput(config) {
        var input = config._i;
        if (isUndefined(input)) {
            config._d = new Date(hooks.now());
        } else if (isDate(input)) {
            config._d = new Date(input.valueOf());
        } else if (typeof input === 'string') {
            configFromString(config);
        } else if (isArray(input)) {
            config._a = map(input.slice(0), function (obj) {
                return parseInt(obj, 10);
            });
            configFromArray(config);
        } else if (isObject(input)) {
            configFromObject(config);
        } else if (isNumber(input)) {
            // from milliseconds
            config._d = new Date(input);
        } else {
            hooks.createFromInputFallback(config);
        }
    }

    function createLocalOrUTC(input, format, locale, strict, isUTC) {
        var c = {};

        if (format === true || format === false) {
            strict = format;
            format = undefined;
        }

        if (locale === true || locale === false) {
            strict = locale;
            locale = undefined;
        }

        if (
            (isObject(input) && isObjectEmpty(input)) ||
            (isArray(input) && input.length === 0)
        ) {
            input = undefined;
        }
        // object construction must be done this way.
        // https://github.com/moment/moment/issues/1423
        c._isAMomentObject = true;
        c._useUTC = c._isUTC = isUTC;
        c._l = locale;
        c._i = input;
        c._f = format;
        c._strict = strict;

        return createFromConfig(c);
    }

    function createLocal(input, format, locale, strict) {
        return createLocalOrUTC(input, format, locale, strict, false);
    }

    var prototypeMin = deprecate(
            'moment().min is deprecated, use moment.max instead. http://momentjs.com/guides/#/warnings/min-max/',
            function () {
                var other = createLocal.apply(null, arguments);
                if (this.isValid() && other.isValid()) {
                    return other < this ? this : other;
                } else {
                    return createInvalid();
                }
            }
        ),
        prototypeMax = deprecate(
            'moment().max is deprecated, use moment.min instead. http://momentjs.com/guides/#/warnings/min-max/',
            function () {
                var other = createLocal.apply(null, arguments);
                if (this.isValid() && other.isValid()) {
                    return other > this ? this : other;
                } else {
                    return createInvalid();
                }
            }
        );

    // Pick a moment m from moments so that m[fn](other) is true for all
    // other. This relies on the function fn to be transitive.
    //
    // moments should either be an array of moment objects or an array, whose
    // first element is an array of moment objects.
    function pickBy(fn, moments) {
        var res, i;
        if (moments.length === 1 && isArray(moments[0])) {
            moments = moments[0];
        }
        if (!moments.length) {
            return createLocal();
        }
        res = moments[0];
        for (i = 1; i < moments.length; ++i) {
            if (!moments[i].isValid() || moments[i][fn](res)) {
                res = moments[i];
            }
        }
        return res;
    }

    // TODO: Use [].sort instead?
    function min() {
        var args = [].slice.call(arguments, 0);

        return pickBy('isBefore', args);
    }

    function max() {
        var args = [].slice.call(arguments, 0);

        return pickBy('isAfter', args);
    }

    var now = function () {
        return Date.now ? Date.now() : +new Date();
    };

    var ordering = [
        'year',
        'quarter',
        'month',
        'week',
        'day',
        'hour',
        'minute',
        'second',
        'millisecond',
    ];

    function isDurationValid(m) {
        var key,
            unitHasDecimal = false,
            i;
        for (key in m) {
            if (
                hasOwnProp(m, key) &&
                !(
                    indexOf.call(ordering, key) !== -1 &&
                    (m[key] == null || !isNaN(m[key]))
                )
            ) {
                return false;
            }
        }

        for (i = 0; i < ordering.length; ++i) {
            if (m[ordering[i]]) {
                if (unitHasDecimal) {
                    return false; // only allow non-integers for smallest unit
                }
                if (parseFloat(m[ordering[i]]) !== toInt(m[ordering[i]])) {
                    unitHasDecimal = true;
                }
            }
        }

        return true;
    }

    function isValid$1() {
        return this._isValid;
    }

    function createInvalid$1() {
        return createDuration(NaN);
    }

    function Duration(duration) {
        var normalizedInput = normalizeObjectUnits(duration),
            years = normalizedInput.year || 0,
            quarters = normalizedInput.quarter || 0,
            months = normalizedInput.month || 0,
            weeks = normalizedInput.week || normalizedInput.isoWeek || 0,
            days = normalizedInput.day || 0,
            hours = normalizedInput.hour || 0,
            minutes = normalizedInput.minute || 0,
            seconds = normalizedInput.second || 0,
            milliseconds = normalizedInput.millisecond || 0;

        this._isValid = isDurationValid(normalizedInput);

        // representation for dateAddRemove
        this._milliseconds =
            +milliseconds +
            seconds * 1e3 + // 1000
            minutes * 6e4 + // 1000 * 60
            hours * 1000 * 60 * 60; //using 1000 * 60 * 60 instead of 36e5 to avoid floating point rounding errors https://github.com/moment/moment/issues/2978
        // Because of dateAddRemove treats 24 hours as different from a
        // day when working around DST, we need to store them separately
        this._days = +days + weeks * 7;
        // It is impossible to translate months into days without knowing
        // which months you are are talking about, so we have to store
        // it separately.
        this._months = +months + quarters * 3 + years * 12;

        this._data = {};

        this._locale = getLocale();

        this._bubble();
    }

    function isDuration(obj) {
        return obj instanceof Duration;
    }

    function absRound(number) {
        if (number < 0) {
            return Math.round(-1 * number) * -1;
        } else {
            return Math.round(number);
        }
    }

    // compare two arrays, return the number of differences
    function compareArrays(array1, array2, dontConvert) {
        var len = Math.min(array1.length, array2.length),
            lengthDiff = Math.abs(array1.length - array2.length),
            diffs = 0,
            i;
        for (i = 0; i < len; i++) {
            if (
                (dontConvert && array1[i] !== array2[i]) ||
                (!dontConvert && toInt(array1[i]) !== toInt(array2[i]))
            ) {
                diffs++;
            }
        }
        return diffs + lengthDiff;
    }

    // FORMATTING

    function offset(token, separator) {
        addFormatToken(token, 0, 0, function () {
            var offset = this.utcOffset(),
                sign = '+';
            if (offset < 0) {
                offset = -offset;
                sign = '-';
            }
            return (
                sign +
                zeroFill(~~(offset / 60), 2) +
                separator +
                zeroFill(~~offset % 60, 2)
            );
        });
    }

    offset('Z', ':');
    offset('ZZ', '');

    // PARSING

    addRegexToken('Z', matchShortOffset);
    addRegexToken('ZZ', matchShortOffset);
    addParseToken(['Z', 'ZZ'], function (input, array, config) {
        config._useUTC = true;
        config._tzm = offsetFromString(matchShortOffset, input);
    });

    // HELPERS

    // timezone chunker
    // '+10:00' > ['10',  '00']
    // '-1530'  > ['-15', '30']
    var chunkOffset = /([\+\-]|\d\d)/gi;

    function offsetFromString(matcher, string) {
        var matches = (string || '').match(matcher),
            chunk,
            parts,
            minutes;

        if (matches === null) {
            return null;
        }

        chunk = matches[matches.length - 1] || [];
        parts = (chunk + '').match(chunkOffset) || ['-', 0, 0];
        minutes = +(parts[1] * 60) + toInt(parts[2]);

        return minutes === 0 ? 0 : parts[0] === '+' ? minutes : -minutes;
    }

    // Return a moment from input, that is local/utc/zone equivalent to model.
    function cloneWithOffset(input, model) {
        var res, diff;
        if (model._isUTC) {
            res = model.clone();
            diff =
                (isMoment(input) || isDate(input)
                    ? input.valueOf()
                    : createLocal(input).valueOf()) - res.valueOf();
            // Use low-level api, because this fn is low-level api.
            res._d.setTime(res._d.valueOf() + diff);
            hooks.updateOffset(res, false);
            return res;
        } else {
            return createLocal(input).local();
        }
    }

    function getDateOffset(m) {
        // On Firefox.24 Date#getTimezoneOffset returns a floating point.
        // https://github.com/moment/moment/pull/1871
        return -Math.round(m._d.getTimezoneOffset());
    }

    // HOOKS

    // This function will be called whenever a moment is mutated.
    // It is intended to keep the offset in sync with the timezone.
    hooks.updateOffset = function () {};

    // MOMENTS

    // keepLocalTime = true means only change the timezone, without
    // affecting the local hour. So 5:31:26 +0300 --[utcOffset(2, true)]-->
    // 5:31:26 +0200 It is possible that 5:31:26 doesn't exist with offset
    // +0200, so we adjust the time as needed, to be valid.
    //
    // Keeping the time actually adds/subtracts (one hour)
    // from the actual represented time. That is why we call updateOffset
    // a second time. In case it wants us to change the offset again
    // _changeInProgress == true case, then we have to adjust, because
    // there is no such time in the given timezone.
    function getSetOffset(input, keepLocalTime, keepMinutes) {
        var offset = this._offset || 0,
            localAdjust;
        if (!this.isValid()) {
            return input != null ? this : NaN;
        }
        if (input != null) {
            if (typeof input === 'string') {
                input = offsetFromString(matchShortOffset, input);
                if (input === null) {
                    return this;
                }
            } else if (Math.abs(input) < 16 && !keepMinutes) {
                input = input * 60;
            }
            if (!this._isUTC && keepLocalTime) {
                localAdjust = getDateOffset(this);
            }
            this._offset = input;
            this._isUTC = true;
            if (localAdjust != null) {
                this.add(localAdjust, 'm');
            }
            if (offset !== input) {
                if (!keepLocalTime || this._changeInProgress) {
                    addSubtract(
                        this,
                        createDuration(input - offset, 'm'),
                        1,
                        false
                    );
                } else if (!this._changeInProgress) {
                    this._changeInProgress = true;
                    hooks.updateOffset(this, true);
                    this._changeInProgress = null;
                }
            }
            return this;
        } else {
            return this._isUTC ? offset : getDateOffset(this);
        }
    }

    function getSetZone(input, keepLocalTime) {
        if (input != null) {
            if (typeof input !== 'string') {
                input = -input;
            }

            this.utcOffset(input, keepLocalTime);

            return this;
        } else {
            return -this.utcOffset();
        }
    }

    function setOffsetToUTC(keepLocalTime) {
        return this.utcOffset(0, keepLocalTime);
    }

    function setOffsetToLocal(keepLocalTime) {
        if (this._isUTC) {
            this.utcOffset(0, keepLocalTime);
            this._isUTC = false;

            if (keepLocalTime) {
                this.subtract(getDateOffset(this), 'm');
            }
        }
        return this;
    }

    function setOffsetToParsedOffset() {
        if (this._tzm != null) {
            this.utcOffset(this._tzm, false, true);
        } else if (typeof this._i === 'string') {
            var tZone = offsetFromString(matchOffset, this._i);
            if (tZone != null) {
                this.utcOffset(tZone);
            } else {
                this.utcOffset(0, true);
            }
        }
        return this;
    }

    function hasAlignedHourOffset(input) {
        if (!this.isValid()) {
            return false;
        }
        input = input ? createLocal(input).utcOffset() : 0;

        return (this.utcOffset() - input) % 60 === 0;
    }

    function isDaylightSavingTime() {
        return (
            this.utcOffset() > this.clone().month(0).utcOffset() ||
            this.utcOffset() > this.clone().month(5).utcOffset()
        );
    }

    function isDaylightSavingTimeShifted() {
        if (!isUndefined(this._isDSTShifted)) {
            return this._isDSTShifted;
        }

        var c = {},
            other;

        copyConfig(c, this);
        c = prepareConfig(c);

        if (c._a) {
            other = c._isUTC ? createUTC(c._a) : createLocal(c._a);
            this._isDSTShifted =
                this.isValid() && compareArrays(c._a, other.toArray()) > 0;
        } else {
            this._isDSTShifted = false;
        }

        return this._isDSTShifted;
    }

    function isLocal() {
        return this.isValid() ? !this._isUTC : false;
    }

    function isUtcOffset() {
        return this.isValid() ? this._isUTC : false;
    }

    function isUtc() {
        return this.isValid() ? this._isUTC && this._offset === 0 : false;
    }

    // ASP.NET json date format regex
    var aspNetRegex = /^(-|\+)?(?:(\d*)[. ])?(\d+):(\d+)(?::(\d+)(\.\d*)?)?$/,
        // from http://docs.closure-library.googlecode.com/git/closure_goog_date_date.js.source.html
        // somewhat more in line with 4.4.3.2 2004 spec, but allows decimal anywhere
        // and further modified to allow for strings containing both week and day
        isoRegex = /^(-|\+)?P(?:([-+]?[0-9,.]*)Y)?(?:([-+]?[0-9,.]*)M)?(?:([-+]?[0-9,.]*)W)?(?:([-+]?[0-9,.]*)D)?(?:T(?:([-+]?[0-9,.]*)H)?(?:([-+]?[0-9,.]*)M)?(?:([-+]?[0-9,.]*)S)?)?$/;

    function createDuration(input, key) {
        var duration = input,
            // matching against regexp is expensive, do it on demand
            match = null,
            sign,
            ret,
            diffRes;

        if (isDuration(input)) {
            duration = {
                ms: input._milliseconds,
                d: input._days,
                M: input._months,
            };
        } else if (isNumber(input) || !isNaN(+input)) {
            duration = {};
            if (key) {
                duration[key] = +input;
            } else {
                duration.milliseconds = +input;
            }
        } else if ((match = aspNetRegex.exec(input))) {
            sign = match[1] === '-' ? -1 : 1;
            duration = {
                y: 0,
                d: toInt(match[DATE]) * sign,
                h: toInt(match[HOUR]) * sign,
                m: toInt(match[MINUTE]) * sign,
                s: toInt(match[SECOND]) * sign,
                ms: toInt(absRound(match[MILLISECOND] * 1000)) * sign, // the millisecond decimal point is included in the match
            };
        } else if ((match = isoRegex.exec(input))) {
            sign = match[1] === '-' ? -1 : 1;
            duration = {
                y: parseIso(match[2], sign),
                M: parseIso(match[3], sign),
                w: parseIso(match[4], sign),
                d: parseIso(match[5], sign),
                h: parseIso(match[6], sign),
                m: parseIso(match[7], sign),
                s: parseIso(match[8], sign),
            };
        } else if (duration == null) {
            // checks for null or undefined
            duration = {};
        } else if (
            typeof duration === 'object' &&
            ('from' in duration || 'to' in duration)
        ) {
            diffRes = momentsDifference(
                createLocal(duration.from),
                createLocal(duration.to)
            );

            duration = {};
            duration.ms = diffRes.milliseconds;
            duration.M = diffRes.months;
        }

        ret = new Duration(duration);

        if (isDuration(input) && hasOwnProp(input, '_locale')) {
            ret._locale = input._locale;
        }

        if (isDuration(input) && hasOwnProp(input, '_isValid')) {
            ret._isValid = input._isValid;
        }

        return ret;
    }

    createDuration.fn = Duration.prototype;
    createDuration.invalid = createInvalid$1;

    function parseIso(inp, sign) {
        // We'd normally use ~~inp for this, but unfortunately it also
        // converts floats to ints.
        // inp may be undefined, so careful calling replace on it.
        var res = inp && parseFloat(inp.replace(',', '.'));
        // apply sign while we're at it
        return (isNaN(res) ? 0 : res) * sign;
    }

    function positiveMomentsDifference(base, other) {
        var res = {};

        res.months =
            other.month() - base.month() + (other.year() - base.year()) * 12;
        if (base.clone().add(res.months, 'M').isAfter(other)) {
            --res.months;
        }

        res.milliseconds = +other - +base.clone().add(res.months, 'M');

        return res;
    }

    function momentsDifference(base, other) {
        var res;
        if (!(base.isValid() && other.isValid())) {
            return { milliseconds: 0, months: 0 };
        }

        other = cloneWithOffset(other, base);
        if (base.isBefore(other)) {
            res = positiveMomentsDifference(base, other);
        } else {
            res = positiveMomentsDifference(other, base);
            res.milliseconds = -res.milliseconds;
            res.months = -res.months;
        }

        return res;
    }

    // TODO: remove 'name' arg after deprecation is removed
    function createAdder(direction, name) {
        return function (val, period) {
            var dur, tmp;
            //invert the arguments, but complain about it
            if (period !== null && !isNaN(+period)) {
                deprecateSimple(
                    name,
                    'moment().' +
                        name +
                        '(period, number) is deprecated. Please use moment().' +
                        name +
                        '(number, period). ' +
                        'See http://momentjs.com/guides/#/warnings/add-inverted-param/ for more info.'
                );
                tmp = val;
                val = period;
                period = tmp;
            }

            dur = createDuration(val, period);
            addSubtract(this, dur, direction);
            return this;
        };
    }

    function addSubtract(mom, duration, isAdding, updateOffset) {
        var milliseconds = duration._milliseconds,
            days = absRound(duration._days),
            months = absRound(duration._months);

        if (!mom.isValid()) {
            // No op
            return;
        }

        updateOffset = updateOffset == null ? true : updateOffset;

        if (months) {
            setMonth(mom, get(mom, 'Month') + months * isAdding);
        }
        if (days) {
            set$1(mom, 'Date', get(mom, 'Date') + days * isAdding);
        }
        if (milliseconds) {
            mom._d.setTime(mom._d.valueOf() + milliseconds * isAdding);
        }
        if (updateOffset) {
            hooks.updateOffset(mom, days || months);
        }
    }

    var add = createAdder(1, 'add'),
        subtract = createAdder(-1, 'subtract');

    function isString(input) {
        return typeof input === 'string' || input instanceof String;
    }

    // type MomentInput = Moment | Date | string | number | (number | string)[] | MomentInputObject | void; // null | undefined
    function isMomentInput(input) {
        return (
            isMoment(input) ||
            isDate(input) ||
            isString(input) ||
            isNumber(input) ||
            isNumberOrStringArray(input) ||
            isMomentInputObject(input) ||
            input === null ||
            input === undefined
        );
    }

    function isMomentInputObject(input) {
        var objectTest = isObject(input) && !isObjectEmpty(input),
            propertyTest = false,
            properties = [
                'years',
                'year',
                'y',
                'months',
                'month',
                'M',
                'days',
                'day',
                'd',
                'dates',
                'date',
                'D',
                'hours',
                'hour',
                'h',
                'minutes',
                'minute',
                'm',
                'seconds',
                'second',
                's',
                'milliseconds',
                'millisecond',
                'ms',
            ],
            i,
            property;

        for (i = 0; i < properties.length; i += 1) {
            property = properties[i];
            propertyTest = propertyTest || hasOwnProp(input, property);
        }

        return objectTest && propertyTest;
    }

    function isNumberOrStringArray(input) {
        var arrayTest = isArray(input),
            dataTypeTest = false;
        if (arrayTest) {
            dataTypeTest =
                input.filter(function (item) {
                    return !isNumber(item) && isString(input);
                }).length === 0;
        }
        return arrayTest && dataTypeTest;
    }

    function isCalendarSpec(input) {
        var objectTest = isObject(input) && !isObjectEmpty(input),
            propertyTest = false,
            properties = [
                'sameDay',
                'nextDay',
                'lastDay',
                'nextWeek',
                'lastWeek',
                'sameElse',
            ],
            i,
            property;

        for (i = 0; i < properties.length; i += 1) {
            property = properties[i];
            propertyTest = propertyTest || hasOwnProp(input, property);
        }

        return objectTest && propertyTest;
    }

    function getCalendarFormat(myMoment, now) {
        var diff = myMoment.diff(now, 'days', true);
        return diff < -6
            ? 'sameElse'
            : diff < -1
            ? 'lastWeek'
            : diff < 0
            ? 'lastDay'
            : diff < 1
            ? 'sameDay'
            : diff < 2
            ? 'nextDay'
            : diff < 7
            ? 'nextWeek'
            : 'sameElse';
    }

    function calendar$1(time, formats) {
        // Support for single parameter, formats only overload to the calendar function
        if (arguments.length === 1) {
            if (!arguments[0]) {
                time = undefined;
                formats = undefined;
            } else if (isMomentInput(arguments[0])) {
                time = arguments[0];
                formats = undefined;
            } else if (isCalendarSpec(arguments[0])) {
                formats = arguments[0];
                time = undefined;
            }
        }
        // We want to compare the start of today, vs this.
        // Getting start-of-today depends on whether we're local/utc/offset or not.
        var now = time || createLocal(),
            sod = cloneWithOffset(now, this).startOf('day'),
            format = hooks.calendarFormat(this, sod) || 'sameElse',
            output =
                formats &&
                (isFunction(formats[format])
                    ? formats[format].call(this, now)
                    : formats[format]);

        return this.format(
            output || this.localeData().calendar(format, this, createLocal(now))
        );
    }

    function clone() {
        return new Moment(this);
    }

    function isAfter(input, units) {
        var localInput = isMoment(input) ? input : createLocal(input);
        if (!(this.isValid() && localInput.isValid())) {
            return false;
        }
        units = normalizeUnits(units) || 'millisecond';
        if (units === 'millisecond') {
            return this.valueOf() > localInput.valueOf();
        } else {
            return localInput.valueOf() < this.clone().startOf(units).valueOf();
        }
    }

    function isBefore(input, units) {
        var localInput = isMoment(input) ? input : createLocal(input);
        if (!(this.isValid() && localInput.isValid())) {
            return false;
        }
        units = normalizeUnits(units) || 'millisecond';
        if (units === 'millisecond') {
            return this.valueOf() < localInput.valueOf();
        } else {
            return this.clone().endOf(units).valueOf() < localInput.valueOf();
        }
    }

    function isBetween(from, to, units, inclusivity) {
        var localFrom = isMoment(from) ? from : createLocal(from),
            localTo = isMoment(to) ? to : createLocal(to);
        if (!(this.isValid() && localFrom.isValid() && localTo.isValid())) {
            return false;
        }
        inclusivity = inclusivity || '()';
        return (
            (inclusivity[0] === '('
                ? this.isAfter(localFrom, units)
                : !this.isBefore(localFrom, units)) &&
            (inclusivity[1] === ')'
                ? this.isBefore(localTo, units)
                : !this.isAfter(localTo, units))
        );
    }

    function isSame(input, units) {
        var localInput = isMoment(input) ? input : createLocal(input),
            inputMs;
        if (!(this.isValid() && localInput.isValid())) {
            return false;
        }
        units = normalizeUnits(units) || 'millisecond';
        if (units === 'millisecond') {
            return this.valueOf() === localInput.valueOf();
        } else {
            inputMs = localInput.valueOf();
            return (
                this.clone().startOf(units).valueOf() <= inputMs &&
                inputMs <= this.clone().endOf(units).valueOf()
            );
        }
    }

    function isSameOrAfter(input, units) {
        return this.isSame(input, units) || this.isAfter(input, units);
    }

    function isSameOrBefore(input, units) {
        return this.isSame(input, units) || this.isBefore(input, units);
    }

    function diff(input, units, asFloat) {
        var that, zoneDelta, output;

        if (!this.isValid()) {
            return NaN;
        }

        that = cloneWithOffset(input, this);

        if (!that.isValid()) {
            return NaN;
        }

        zoneDelta = (that.utcOffset() - this.utcOffset()) * 6e4;

        units = normalizeUnits(units);

        switch (units) {
            case 'year':
                output = monthDiff(this, that) / 12;
                break;
            case 'month':
                output = monthDiff(this, that);
                break;
            case 'quarter':
                output = monthDiff(this, that) / 3;
                break;
            case 'second':
                output = (this - that) / 1e3;
                break; // 1000
            case 'minute':
                output = (this - that) / 6e4;
                break; // 1000 * 60
            case 'hour':
                output = (this - that) / 36e5;
                break; // 1000 * 60 * 60
            case 'day':
                output = (this - that - zoneDelta) / 864e5;
                break; // 1000 * 60 * 60 * 24, negate dst
            case 'week':
                output = (this - that - zoneDelta) / 6048e5;
                break; // 1000 * 60 * 60 * 24 * 7, negate dst
            default:
                output = this - that;
        }

        return asFloat ? output : absFloor(output);
    }

    function monthDiff(a, b) {
        if (a.date() < b.date()) {
            // end-of-month calculations work correct when the start month has more
            // days than the end month.
            return -monthDiff(b, a);
        }
        // difference in months
        var wholeMonthDiff = (b.year() - a.year()) * 12 + (b.month() - a.month()),
            // b is in (anchor - 1 month, anchor + 1 month)
            anchor = a.clone().add(wholeMonthDiff, 'months'),
            anchor2,
            adjust;

        if (b - anchor < 0) {
            anchor2 = a.clone().add(wholeMonthDiff - 1, 'months');
            // linear across the month
            adjust = (b - anchor) / (anchor - anchor2);
        } else {
            anchor2 = a.clone().add(wholeMonthDiff + 1, 'months');
            // linear across the month
            adjust = (b - anchor) / (anchor2 - anchor);
        }

        //check for negative zero, return zero if negative zero
        return -(wholeMonthDiff + adjust) || 0;
    }

    hooks.defaultFormat = 'YYYY-MM-DDTHH:mm:ssZ';
    hooks.defaultFormatUtc = 'YYYY-MM-DDTHH:mm:ss[Z]';

    function toString() {
        return this.clone().locale('en').format('ddd MMM DD YYYY HH:mm:ss [GMT]ZZ');
    }

    function toISOString(keepOffset) {
        if (!this.isValid()) {
            return null;
        }
        var utc = keepOffset !== true,
            m = utc ? this.clone().utc() : this;
        if (m.year() < 0 || m.year() > 9999) {
            return formatMoment(
                m,
                utc
                    ? 'YYYYYY-MM-DD[T]HH:mm:ss.SSS[Z]'
                    : 'YYYYYY-MM-DD[T]HH:mm:ss.SSSZ'
            );
        }
        if (isFunction(Date.prototype.toISOString)) {
            // native implementation is ~50x faster, use it when we can
            if (utc) {
                return this.toDate().toISOString();
            } else {
                return new Date(this.valueOf() + this.utcOffset() * 60 * 1000)
                    .toISOString()
                    .replace('Z', formatMoment(m, 'Z'));
            }
        }
        return formatMoment(
            m,
            utc ? 'YYYY-MM-DD[T]HH:mm:ss.SSS[Z]' : 'YYYY-MM-DD[T]HH:mm:ss.SSSZ'
        );
    }

    /**
     * Return a human readable representation of a moment that can
     * also be evaluated to get a new moment which is the same
     *
     * @link https://nodejs.org/dist/latest/docs/api/util.html#util_custom_inspect_function_on_objects
     */
    function inspect() {
        if (!this.isValid()) {
            return 'moment.invalid(/* ' + this._i + ' */)';
        }
        var func = 'moment',
            zone = '',
            prefix,
            year,
            datetime,
            suffix;
        if (!this.isLocal()) {
            func = this.utcOffset() === 0 ? 'moment.utc' : 'moment.parseZone';
            zone = 'Z';
        }
        prefix = '[' + func + '("]';
        year = 0 <= this.year() && this.year() <= 9999 ? 'YYYY' : 'YYYYYY';
        datetime = '-MM-DD[T]HH:mm:ss.SSS';
        suffix = zone + '[")]';

        return this.format(prefix + year + datetime + suffix);
    }

    function format(inputString) {
        if (!inputString) {
            inputString = this.isUtc()
                ? hooks.defaultFormatUtc
                : hooks.defaultFormat;
        }
        var output = formatMoment(this, inputString);
        return this.localeData().postformat(output);
    }

    function from(time, withoutSuffix) {
        if (
            this.isValid() &&
            ((isMoment(time) && time.isValid()) || createLocal(time).isValid())
        ) {
            return createDuration({ to: this, from: time })
                .locale(this.locale())
                .humanize(!withoutSuffix);
        } else {
            return this.localeData().invalidDate();
        }
    }

    function fromNow(withoutSuffix) {
        return this.from(createLocal(), withoutSuffix);
    }

    function to(time, withoutSuffix) {
        if (
            this.isValid() &&
            ((isMoment(time) && time.isValid()) || createLocal(time).isValid())
        ) {
            return createDuration({ from: this, to: time })
                .locale(this.locale())
                .humanize(!withoutSuffix);
        } else {
            return this.localeData().invalidDate();
        }
    }

    function toNow(withoutSuffix) {
        return this.to(createLocal(), withoutSuffix);
    }

    // If passed a locale key, it will set the locale for this
    // instance.  Otherwise, it will return the locale configuration
    // variables for this instance.
    function locale(key) {
        var newLocaleData;

        if (key === undefined) {
            return this._locale._abbr;
        } else {
            newLocaleData = getLocale(key);
            if (newLocaleData != null) {
                this._locale = newLocaleData;
            }
            return this;
        }
    }

    var lang = deprecate(
        'moment().lang() is deprecated. Instead, use moment().localeData() to get the language configuration. Use moment().locale() to change languages.',
        function (key) {
            if (key === undefined) {
                return this.localeData();
            } else {
                return this.locale(key);
            }
        }
    );

    function localeData() {
        return this._locale;
    }

    var MS_PER_SECOND = 1000,
        MS_PER_MINUTE = 60 * MS_PER_SECOND,
        MS_PER_HOUR = 60 * MS_PER_MINUTE,
        MS_PER_400_YEARS = (365 * 400 + 97) * 24 * MS_PER_HOUR;

    // actual modulo - handles negative numbers (for dates before 1970):
    function mod$1(dividend, divisor) {
        return ((dividend % divisor) + divisor) % divisor;
    }

    function localStartOfDate(y, m, d) {
        // the date constructor remaps years 0-99 to 1900-1999
        if (y < 100 && y >= 0) {
            // preserve leap years using a full 400 year cycle, then reset
            return new Date(y + 400, m, d) - MS_PER_400_YEARS;
        } else {
            return new Date(y, m, d).valueOf();
        }
    }

    function utcStartOfDate(y, m, d) {
        // Date.UTC remaps years 0-99 to 1900-1999
        if (y < 100 && y >= 0) {
            // preserve leap years using a full 400 year cycle, then reset
            return Date.UTC(y + 400, m, d) - MS_PER_400_YEARS;
        } else {
            return Date.UTC(y, m, d);
        }
    }

    function startOf(units) {
        var time, startOfDate;
        units = normalizeUnits(units);
        if (units === undefined || units === 'millisecond' || !this.isValid()) {
            return this;
        }

        startOfDate = this._isUTC ? utcStartOfDate : localStartOfDate;

        switch (units) {
            case 'year':
                time = startOfDate(this.year(), 0, 1);
                break;
            case 'quarter':
                time = startOfDate(
                    this.year(),
                    this.month() - (this.month() % 3),
                    1
                );
                break;
            case 'month':
                time = startOfDate(this.year(), this.month(), 1);
                break;
            case 'week':
                time = startOfDate(
                    this.year(),
                    this.month(),
                    this.date() - this.weekday()
                );
                break;
            case 'isoWeek':
                time = startOfDate(
                    this.year(),
                    this.month(),
                    this.date() - (this.isoWeekday() - 1)
                );
                break;
            case 'day':
            case 'date':
                time = startOfDate(this.year(), this.month(), this.date());
                break;
            case 'hour':
                time = this._d.valueOf();
                time -= mod$1(
                    time + (this._isUTC ? 0 : this.utcOffset() * MS_PER_MINUTE),
                    MS_PER_HOUR
                );
                break;
            case 'minute':
                time = this._d.valueOf();
                time -= mod$1(time, MS_PER_MINUTE);
                break;
            case 'second':
                time = this._d.valueOf();
                time -= mod$1(time, MS_PER_SECOND);
                break;
        }

        this._d.setTime(time);
        hooks.updateOffset(this, true);
        return this;
    }

    function endOf(units) {
        var time, startOfDate;
        units = normalizeUnits(units);
        if (units === undefined || units === 'millisecond' || !this.isValid()) {
            return this;
        }

        startOfDate = this._isUTC ? utcStartOfDate : localStartOfDate;

        switch (units) {
            case 'year':
                time = startOfDate(this.year() + 1, 0, 1) - 1;
                break;
            case 'quarter':
                time =
                    startOfDate(
                        this.year(),
                        this.month() - (this.month() % 3) + 3,
                        1
                    ) - 1;
                break;
            case 'month':
                time = startOfDate(this.year(), this.month() + 1, 1) - 1;
                break;
            case 'week':
                time =
                    startOfDate(
                        this.year(),
                        this.month(),
                        this.date() - this.weekday() + 7
                    ) - 1;
                break;
            case 'isoWeek':
                time =
                    startOfDate(
                        this.year(),
                        this.month(),
                        this.date() - (this.isoWeekday() - 1) + 7
                    ) - 1;
                break;
            case 'day':
            case 'date':
                time = startOfDate(this.year(), this.month(), this.date() + 1) - 1;
                break;
            case 'hour':
                time = this._d.valueOf();
                time +=
                    MS_PER_HOUR -
                    mod$1(
                        time + (this._isUTC ? 0 : this.utcOffset() * MS_PER_MINUTE),
                        MS_PER_HOUR
                    ) -
                    1;
                break;
            case 'minute':
                time = this._d.valueOf();
                time += MS_PER_MINUTE - mod$1(time, MS_PER_MINUTE) - 1;
                break;
            case 'second':
                time = this._d.valueOf();
                time += MS_PER_SECOND - mod$1(time, MS_PER_SECOND) - 1;
                break;
        }

        this._d.setTime(time);
        hooks.updateOffset(this, true);
        return this;
    }

    function valueOf() {
        return this._d.valueOf() - (this._offset || 0) * 60000;
    }

    function unix() {
        return Math.floor(this.valueOf() / 1000);
    }

    function toDate() {
        return new Date(this.valueOf());
    }

    function toArray() {
        var m = this;
        return [
            m.year(),
            m.month(),
            m.date(),
            m.hour(),
            m.minute(),
            m.second(),
            m.millisecond(),
        ];
    }

    function toObject() {
        var m = this;
        return {
            years: m.year(),
            months: m.month(),
            date: m.date(),
            hours: m.hours(),
            minutes: m.minutes(),
            seconds: m.seconds(),
            milliseconds: m.milliseconds(),
        };
    }

    function toJSON() {
        // new Date(NaN).toJSON() === null
        return this.isValid() ? this.toISOString() : null;
    }

    function isValid$2() {
        return isValid(this);
    }

    function parsingFlags() {
        return extend({}, getParsingFlags(this));
    }

    function invalidAt() {
        return getParsingFlags(this).overflow;
    }

    function creationData() {
        return {
            input: this._i,
            format: this._f,
            locale: this._locale,
            isUTC: this._isUTC,
            strict: this._strict,
        };
    }

    addFormatToken('N', 0, 0, 'eraAbbr');
    addFormatToken('NN', 0, 0, 'eraAbbr');
    addFormatToken('NNN', 0, 0, 'eraAbbr');
    addFormatToken('NNNN', 0, 0, 'eraName');
    addFormatToken('NNNNN', 0, 0, 'eraNarrow');

    addFormatToken('y', ['y', 1], 'yo', 'eraYear');
    addFormatToken('y', ['yy', 2], 0, 'eraYear');
    addFormatToken('y', ['yyy', 3], 0, 'eraYear');
    addFormatToken('y', ['yyyy', 4], 0, 'eraYear');

    addRegexToken('N', matchEraAbbr);
    addRegexToken('NN', matchEraAbbr);
    addRegexToken('NNN', matchEraAbbr);
    addRegexToken('NNNN', matchEraName);
    addRegexToken('NNNNN', matchEraNarrow);

    addParseToken(['N', 'NN', 'NNN', 'NNNN', 'NNNNN'], function (
        input,
        array,
        config,
        token
    ) {
        var era = config._locale.erasParse(input, token, config._strict);
        if (era) {
            getParsingFlags(config).era = era;
        } else {
            getParsingFlags(config).invalidEra = input;
        }
    });

    addRegexToken('y', matchUnsigned);
    addRegexToken('yy', matchUnsigned);
    addRegexToken('yyy', matchUnsigned);
    addRegexToken('yyyy', matchUnsigned);
    addRegexToken('yo', matchEraYearOrdinal);

    addParseToken(['y', 'yy', 'yyy', 'yyyy'], YEAR);
    addParseToken(['yo'], function (input, array, config, token) {
        var match;
        if (config._locale._eraYearOrdinalRegex) {
            match = input.match(config._locale._eraYearOrdinalRegex);
        }

        if (config._locale.eraYearOrdinalParse) {
            array[YEAR] = config._locale.eraYearOrdinalParse(input, match);
        } else {
            array[YEAR] = parseInt(input, 10);
        }
    });

    function localeEras(m, format) {
        var i,
            l,
            date,
            eras = this._eras || getLocale('en')._eras;
        for (i = 0, l = eras.length; i < l; ++i) {
            switch (typeof eras[i].since) {
                case 'string':
                    // truncate time
                    date = hooks(eras[i].since).startOf('day');
                    eras[i].since = date.valueOf();
                    break;
            }

            switch (typeof eras[i].until) {
                case 'undefined':
                    eras[i].until = +Infinity;
                    break;
                case 'string':
                    // truncate time
                    date = hooks(eras[i].until).startOf('day').valueOf();
                    eras[i].until = date.valueOf();
                    break;
            }
        }
        return eras;
    }

    function localeErasParse(eraName, format, strict) {
        var i,
            l,
            eras = this.eras(),
            name,
            abbr,
            narrow;
        eraName = eraName.toUpperCase();

        for (i = 0, l = eras.length; i < l; ++i) {
            name = eras[i].name.toUpperCase();
            abbr = eras[i].abbr.toUpperCase();
            narrow = eras[i].narrow.toUpperCase();

            if (strict) {
                switch (format) {
                    case 'N':
                    case 'NN':
                    case 'NNN':
                        if (abbr === eraName) {
                            return eras[i];
                        }
                        break;

                    case 'NNNN':
                        if (name === eraName) {
                            return eras[i];
                        }
                        break;

                    case 'NNNNN':
                        if (narrow === eraName) {
                            return eras[i];
                        }
                        break;
                }
            } else if ([name, abbr, narrow].indexOf(eraName) >= 0) {
                return eras[i];
            }
        }
    }

    function localeErasConvertYear(era, year) {
        var dir = era.since <= era.until ? +1 : -1;
        if (year === undefined) {
            return hooks(era.since).year();
        } else {
            return hooks(era.since).year() + (year - era.offset) * dir;
        }
    }

    function getEraName() {
        var i,
            l,
            val,
            eras = this.localeData().eras();
        for (i = 0, l = eras.length; i < l; ++i) {
            // truncate time
            val = this.clone().startOf('day').valueOf();

            if (eras[i].since <= val && val <= eras[i].until) {
                return eras[i].name;
            }
            if (eras[i].until <= val && val <= eras[i].since) {
                return eras[i].name;
            }
        }

        return '';
    }

    function getEraNarrow() {
        var i,
            l,
            val,
            eras = this.localeData().eras();
        for (i = 0, l = eras.length; i < l; ++i) {
            // truncate time
            val = this.clone().startOf('day').valueOf();

            if (eras[i].since <= val && val <= eras[i].until) {
                return eras[i].narrow;
            }
            if (eras[i].until <= val && val <= eras[i].since) {
                return eras[i].narrow;
            }
        }

        return '';
    }

    function getEraAbbr() {
        var i,
            l,
            val,
            eras = this.localeData().eras();
        for (i = 0, l = eras.length; i < l; ++i) {
            // truncate time
            val = this.clone().startOf('day').valueOf();

            if (eras[i].since <= val && val <= eras[i].until) {
                return eras[i].abbr;
            }
            if (eras[i].until <= val && val <= eras[i].since) {
                return eras[i].abbr;
            }
        }

        return '';
    }

    function getEraYear() {
        var i,
            l,
            dir,
            val,
            eras = this.localeData().eras();
        for (i = 0, l = eras.length; i < l; ++i) {
            dir = eras[i].since <= eras[i].until ? +1 : -1;

            // truncate time
            val = this.clone().startOf('day').valueOf();

            if (
                (eras[i].since <= val && val <= eras[i].until) ||
                (eras[i].until <= val && val <= eras[i].since)
            ) {
                return (
                    (this.year() - hooks(eras[i].since).year()) * dir +
                    eras[i].offset
                );
            }
        }

        return this.year();
    }

    function erasNameRegex(isStrict) {
        if (!hasOwnProp(this, '_erasNameRegex')) {
            computeErasParse.call(this);
        }
        return isStrict ? this._erasNameRegex : this._erasRegex;
    }

    function erasAbbrRegex(isStrict) {
        if (!hasOwnProp(this, '_erasAbbrRegex')) {
            computeErasParse.call(this);
        }
        return isStrict ? this._erasAbbrRegex : this._erasRegex;
    }

    function erasNarrowRegex(isStrict) {
        if (!hasOwnProp(this, '_erasNarrowRegex')) {
            computeErasParse.call(this);
        }
        return isStrict ? this._erasNarrowRegex : this._erasRegex;
    }

    function matchEraAbbr(isStrict, locale) {
        return locale.erasAbbrRegex(isStrict);
    }

    function matchEraName(isStrict, locale) {
        return locale.erasNameRegex(isStrict);
    }

    function matchEraNarrow(isStrict, locale) {
        return locale.erasNarrowRegex(isStrict);
    }

    function matchEraYearOrdinal(isStrict, locale) {
        return locale._eraYearOrdinalRegex || matchUnsigned;
    }

    function computeErasParse() {
        var abbrPieces = [],
            namePieces = [],
            narrowPieces = [],
            mixedPieces = [],
            i,
            l,
            eras = this.eras();

        for (i = 0, l = eras.length; i < l; ++i) {
            namePieces.push(regexEscape(eras[i].name));
            abbrPieces.push(regexEscape(eras[i].abbr));
            narrowPieces.push(regexEscape(eras[i].narrow));

            mixedPieces.push(regexEscape(eras[i].name));
            mixedPieces.push(regexEscape(eras[i].abbr));
            mixedPieces.push(regexEscape(eras[i].narrow));
        }

        this._erasRegex = new RegExp('^(' + mixedPieces.join('|') + ')', 'i');
        this._erasNameRegex = new RegExp('^(' + namePieces.join('|') + ')', 'i');
        this._erasAbbrRegex = new RegExp('^(' + abbrPieces.join('|') + ')', 'i');
        this._erasNarrowRegex = new RegExp(
            '^(' + narrowPieces.join('|') + ')',
            'i'
        );
    }

    // FORMATTING

    addFormatToken(0, ['gg', 2], 0, function () {
        return this.weekYear() % 100;
    });

    addFormatToken(0, ['GG', 2], 0, function () {
        return this.isoWeekYear() % 100;
    });

    function addWeekYearFormatToken(token, getter) {
        addFormatToken(0, [token, token.length], 0, getter);
    }

    addWeekYearFormatToken('gggg', 'weekYear');
    addWeekYearFormatToken('ggggg', 'weekYear');
    addWeekYearFormatToken('GGGG', 'isoWeekYear');
    addWeekYearFormatToken('GGGGG', 'isoWeekYear');

    // ALIASES

    addUnitAlias('weekYear', 'gg');
    addUnitAlias('isoWeekYear', 'GG');

    // PRIORITY

    addUnitPriority('weekYear', 1);
    addUnitPriority('isoWeekYear', 1);

    // PARSING

    addRegexToken('G', matchSigned);
    addRegexToken('g', matchSigned);
    addRegexToken('GG', match1to2, match2);
    addRegexToken('gg', match1to2, match2);
    addRegexToken('GGGG', match1to4, match4);
    addRegexToken('gggg', match1to4, match4);
    addRegexToken('GGGGG', match1to6, match6);
    addRegexToken('ggggg', match1to6, match6);

    addWeekParseToken(['gggg', 'ggggg', 'GGGG', 'GGGGG'], function (
        input,
        week,
        config,
        token
    ) {
        week[token.substr(0, 2)] = toInt(input);
    });

    addWeekParseToken(['gg', 'GG'], function (input, week, config, token) {
        week[token] = hooks.parseTwoDigitYear(input);
    });

    // MOMENTS

    function getSetWeekYear(input) {
        return getSetWeekYearHelper.call(
            this,
            input,
            this.week(),
            this.weekday(),
            this.localeData()._week.dow,
            this.localeData()._week.doy
        );
    }

    function getSetISOWeekYear(input) {
        return getSetWeekYearHelper.call(
            this,
            input,
            this.isoWeek(),
            this.isoWeekday(),
            1,
            4
        );
    }

    function getISOWeeksInYear() {
        return weeksInYear(this.year(), 1, 4);
    }

    function getISOWeeksInISOWeekYear() {
        return weeksInYear(this.isoWeekYear(), 1, 4);
    }

    function getWeeksInYear() {
        var weekInfo = this.localeData()._week;
        return weeksInYear(this.year(), weekInfo.dow, weekInfo.doy);
    }

    function getWeeksInWeekYear() {
        var weekInfo = this.localeData()._week;
        return weeksInYear(this.weekYear(), weekInfo.dow, weekInfo.doy);
    }

    function getSetWeekYearHelper(input, week, weekday, dow, doy) {
        var weeksTarget;
        if (input == null) {
            return weekOfYear(this, dow, doy).year;
        } else {
            weeksTarget = weeksInYear(input, dow, doy);
            if (week > weeksTarget) {
                week = weeksTarget;
            }
            return setWeekAll.call(this, input, week, weekday, dow, doy);
        }
    }

    function setWeekAll(weekYear, week, weekday, dow, doy) {
        var dayOfYearData = dayOfYearFromWeeks(weekYear, week, weekday, dow, doy),
            date = createUTCDate(dayOfYearData.year, 0, dayOfYearData.dayOfYear);

        this.year(date.getUTCFullYear());
        this.month(date.getUTCMonth());
        this.date(date.getUTCDate());
        return this;
    }

    // FORMATTING

    addFormatToken('Q', 0, 'Qo', 'quarter');

    // ALIASES

    addUnitAlias('quarter', 'Q');

    // PRIORITY

    addUnitPriority('quarter', 7);

    // PARSING

    addRegexToken('Q', match1);
    addParseToken('Q', function (input, array) {
        array[MONTH] = (toInt(input) - 1) * 3;
    });

    // MOMENTS

    function getSetQuarter(input) {
        return input == null
            ? Math.ceil((this.month() + 1) / 3)
            : this.month((input - 1) * 3 + (this.month() % 3));
    }

    // FORMATTING

    addFormatToken('D', ['DD', 2], 'Do', 'date');

    // ALIASES

    addUnitAlias('date', 'D');

    // PRIORITY
    addUnitPriority('date', 9);

    // PARSING

    addRegexToken('D', match1to2);
    addRegexToken('DD', match1to2, match2);
    addRegexToken('Do', function (isStrict, locale) {
        // TODO: Remove "ordinalParse" fallback in next major release.
        return isStrict
            ? locale._dayOfMonthOrdinalParse || locale._ordinalParse
            : locale._dayOfMonthOrdinalParseLenient;
    });

    addParseToken(['D', 'DD'], DATE);
    addParseToken('Do', function (input, array) {
        array[DATE] = toInt(input.match(match1to2)[0]);
    });

    // MOMENTS

    var getSetDayOfMonth = makeGetSet('Date', true);

    // FORMATTING

    addFormatToken('DDD', ['DDDD', 3], 'DDDo', 'dayOfYear');

    // ALIASES

    addUnitAlias('dayOfYear', 'DDD');

    // PRIORITY
    addUnitPriority('dayOfYear', 4);

    // PARSING

    addRegexToken('DDD', match1to3);
    addRegexToken('DDDD', match3);
    addParseToken(['DDD', 'DDDD'], function (input, array, config) {
        config._dayOfYear = toInt(input);
    });

    // HELPERS

    // MOMENTS

    function getSetDayOfYear(input) {
        var dayOfYear =
            Math.round(
                (this.clone().startOf('day') - this.clone().startOf('year')) / 864e5
            ) + 1;
        return input == null ? dayOfYear : this.add(input - dayOfYear, 'd');
    }

    // FORMATTING

    addFormatToken('m', ['mm', 2], 0, 'minute');

    // ALIASES

    addUnitAlias('minute', 'm');

    // PRIORITY

    addUnitPriority('minute', 14);

    // PARSING

    addRegexToken('m', match1to2);
    addRegexToken('mm', match1to2, match2);
    addParseToken(['m', 'mm'], MINUTE);

    // MOMENTS

    var getSetMinute = makeGetSet('Minutes', false);

    // FORMATTING

    addFormatToken('s', ['ss', 2], 0, 'second');

    // ALIASES

    addUnitAlias('second', 's');

    // PRIORITY

    addUnitPriority('second', 15);

    // PARSING

    addRegexToken('s', match1to2);
    addRegexToken('ss', match1to2, match2);
    addParseToken(['s', 'ss'], SECOND);

    // MOMENTS

    var getSetSecond = makeGetSet('Seconds', false);

    // FORMATTING

    addFormatToken('S', 0, 0, function () {
        return ~~(this.millisecond() / 100);
    });

    addFormatToken(0, ['SS', 2], 0, function () {
        return ~~(this.millisecond() / 10);
    });

    addFormatToken(0, ['SSS', 3], 0, 'millisecond');
    addFormatToken(0, ['SSSS', 4], 0, function () {
        return this.millisecond() * 10;
    });
    addFormatToken(0, ['SSSSS', 5], 0, function () {
        return this.millisecond() * 100;
    });
    addFormatToken(0, ['SSSSSS', 6], 0, function () {
        return this.millisecond() * 1000;
    });
    addFormatToken(0, ['SSSSSSS', 7], 0, function () {
        return this.millisecond() * 10000;
    });
    addFormatToken(0, ['SSSSSSSS', 8], 0, function () {
        return this.millisecond() * 100000;
    });
    addFormatToken(0, ['SSSSSSSSS', 9], 0, function () {
        return this.millisecond() * 1000000;
    });

    // ALIASES

    addUnitAlias('millisecond', 'ms');

    // PRIORITY

    addUnitPriority('millisecond', 16);

    // PARSING

    addRegexToken('S', match1to3, match1);
    addRegexToken('SS', match1to3, match2);
    addRegexToken('SSS', match1to3, match3);

    var token, getSetMillisecond;
    for (token = 'SSSS'; token.length <= 9; token += 'S') {
        addRegexToken(token, matchUnsigned);
    }

    function parseMs(input, array) {
        array[MILLISECOND] = toInt(('0.' + input) * 1000);
    }

    for (token = 'S'; token.length <= 9; token += 'S') {
        addParseToken(token, parseMs);
    }

    getSetMillisecond = makeGetSet('Milliseconds', false);

    // FORMATTING

    addFormatToken('z', 0, 0, 'zoneAbbr');
    addFormatToken('zz', 0, 0, 'zoneName');

    // MOMENTS

    function getZoneAbbr() {
        return this._isUTC ? 'UTC' : '';
    }

    function getZoneName() {
        return this._isUTC ? 'Coordinated Universal Time' : '';
    }

    var proto = Moment.prototype;

    proto.add = add;
    proto.calendar = calendar$1;
    proto.clone = clone;
    proto.diff = diff;
    proto.endOf = endOf;
    proto.format = format;
    proto.from = from;
    proto.fromNow = fromNow;
    proto.to = to;
    proto.toNow = toNow;
    proto.get = stringGet;
    proto.invalidAt = invalidAt;
    proto.isAfter = isAfter;
    proto.isBefore = isBefore;
    proto.isBetween = isBetween;
    proto.isSame = isSame;
    proto.isSameOrAfter = isSameOrAfter;
    proto.isSameOrBefore = isSameOrBefore;
    proto.isValid = isValid$2;
    proto.lang = lang;
    proto.locale = locale;
    proto.localeData = localeData;
    proto.max = prototypeMax;
    proto.min = prototypeMin;
    proto.parsingFlags = parsingFlags;
    proto.set = stringSet;
    proto.startOf = startOf;
    proto.subtract = subtract;
    proto.toArray = toArray;
    proto.toObject = toObject;
    proto.toDate = toDate;
    proto.toISOString = toISOString;
    proto.inspect = inspect;
    if (typeof Symbol !== 'undefined' && Symbol.for != null) {
        proto[Symbol.for('nodejs.util.inspect.custom')] = function () {
            return 'Moment<' + this.format() + '>';
        };
    }
    proto.toJSON = toJSON;
    proto.toString = toString;
    proto.unix = unix;
    proto.valueOf = valueOf;
    proto.creationData = creationData;
    proto.eraName = getEraName;
    proto.eraNarrow = getEraNarrow;
    proto.eraAbbr = getEraAbbr;
    proto.eraYear = getEraYear;
    proto.year = getSetYear;
    proto.isLeapYear = getIsLeapYear;
    proto.weekYear = getSetWeekYear;
    proto.isoWeekYear = getSetISOWeekYear;
    proto.quarter = proto.quarters = getSetQuarter;
    proto.month = getSetMonth;
    proto.daysInMonth = getDaysInMonth;
    proto.week = proto.weeks = getSetWeek;
    proto.isoWeek = proto.isoWeeks = getSetISOWeek;
    proto.weeksInYear = getWeeksInYear;
    proto.weeksInWeekYear = getWeeksInWeekYear;
    proto.isoWeeksInYear = getISOWeeksInYear;
    proto.isoWeeksInISOWeekYear = getISOWeeksInISOWeekYear;
    proto.date = getSetDayOfMonth;
    proto.day = proto.days = getSetDayOfWeek;
    proto.weekday = getSetLocaleDayOfWeek;
    proto.isoWeekday = getSetISODayOfWeek;
    proto.dayOfYear = getSetDayOfYear;
    proto.hour = proto.hours = getSetHour;
    proto.minute = proto.minutes = getSetMinute;
    proto.second = proto.seconds = getSetSecond;
    proto.millisecond = proto.milliseconds = getSetMillisecond;
    proto.utcOffset = getSetOffset;
    proto.utc = setOffsetToUTC;
    proto.local = setOffsetToLocal;
    proto.parseZone = setOffsetToParsedOffset;
    proto.hasAlignedHourOffset = hasAlignedHourOffset;
    proto.isDST = isDaylightSavingTime;
    proto.isLocal = isLocal;
    proto.isUtcOffset = isUtcOffset;
    proto.isUtc = isUtc;
    proto.isUTC = isUtc;
    proto.zoneAbbr = getZoneAbbr;
    proto.zoneName = getZoneName;
    proto.dates = deprecate(
        'dates accessor is deprecated. Use date instead.',
        getSetDayOfMonth
    );
    proto.months = deprecate(
        'months accessor is deprecated. Use month instead',
        getSetMonth
    );
    proto.years = deprecate(
        'years accessor is deprecated. Use year instead',
        getSetYear
    );
    proto.zone = deprecate(
        'moment().zone is deprecated, use moment().utcOffset instead. http://momentjs.com/guides/#/warnings/zone/',
        getSetZone
    );
    proto.isDSTShifted = deprecate(
        'isDSTShifted is deprecated. See http://momentjs.com/guides/#/warnings/dst-shifted/ for more information',
        isDaylightSavingTimeShifted
    );

    function createUnix(input) {
        return createLocal(input * 1000);
    }

    function createInZone() {
        return createLocal.apply(null, arguments).parseZone();
    }

    function preParsePostFormat(string) {
        return string;
    }

    var proto$1 = Locale.prototype;

    proto$1.calendar = calendar;
    proto$1.longDateFormat = longDateFormat;
    proto$1.invalidDate = invalidDate;
    proto$1.ordinal = ordinal;
    proto$1.preparse = preParsePostFormat;
    proto$1.postformat = preParsePostFormat;
    proto$1.relativeTime = relativeTime;
    proto$1.pastFuture = pastFuture;
    proto$1.set = set;
    proto$1.eras = localeEras;
    proto$1.erasParse = localeErasParse;
    proto$1.erasConvertYear = localeErasConvertYear;
    proto$1.erasAbbrRegex = erasAbbrRegex;
    proto$1.erasNameRegex = erasNameRegex;
    proto$1.erasNarrowRegex = erasNarrowRegex;

    proto$1.months = localeMonths;
    proto$1.monthsShort = localeMonthsShort;
    proto$1.monthsParse = localeMonthsParse;
    proto$1.monthsRegex = monthsRegex;
    proto$1.monthsShortRegex = monthsShortRegex;
    proto$1.week = localeWeek;
    proto$1.firstDayOfYear = localeFirstDayOfYear;
    proto$1.firstDayOfWeek = localeFirstDayOfWeek;

    proto$1.weekdays = localeWeekdays;
    proto$1.weekdaysMin = localeWeekdaysMin;
    proto$1.weekdaysShort = localeWeekdaysShort;
    proto$1.weekdaysParse = localeWeekdaysParse;

    proto$1.weekdaysRegex = weekdaysRegex;
    proto$1.weekdaysShortRegex = weekdaysShortRegex;
    proto$1.weekdaysMinRegex = weekdaysMinRegex;

    proto$1.isPM = localeIsPM;
    proto$1.meridiem = localeMeridiem;

    function get$1(format, index, field, setter) {
        var locale = getLocale(),
            utc = createUTC().set(setter, index);
        return locale[field](utc, format);
    }

    function listMonthsImpl(format, index, field) {
        if (isNumber(format)) {
            index = format;
            format = undefined;
        }

        format = format || '';

        if (index != null) {
            return get$1(format, index, field, 'month');
        }

        var i,
            out = [];
        for (i = 0; i < 12; i++) {
            out[i] = get$1(format, i, field, 'month');
        }
        return out;
    }

    // ()
    // (5)
    // (fmt, 5)
    // (fmt)
    // (true)
    // (true, 5)
    // (true, fmt, 5)
    // (true, fmt)
    function listWeekdaysImpl(localeSorted, format, index, field) {
        if (typeof localeSorted === 'boolean') {
            if (isNumber(format)) {
                index = format;
                format = undefined;
            }

            format = format || '';
        } else {
            format = localeSorted;
            index = format;
            localeSorted = false;

            if (isNumber(format)) {
                index = format;
                format = undefined;
            }

            format = format || '';
        }

        var locale = getLocale(),
            shift = localeSorted ? locale._week.dow : 0,
            i,
            out = [];

        if (index != null) {
            return get$1(format, (index + shift) % 7, field, 'day');
        }

        for (i = 0; i < 7; i++) {
            out[i] = get$1(format, (i + shift) % 7, field, 'day');
        }
        return out;
    }

    function listMonths(format, index) {
        return listMonthsImpl(format, index, 'months');
    }

    function listMonthsShort(format, index) {
        return listMonthsImpl(format, index, 'monthsShort');
    }

    function listWeekdays(localeSorted, format, index) {
        return listWeekdaysImpl(localeSorted, format, index, 'weekdays');
    }

    function listWeekdaysShort(localeSorted, format, index) {
        return listWeekdaysImpl(localeSorted, format, index, 'weekdaysShort');
    }

    function listWeekdaysMin(localeSorted, format, index) {
        return listWeekdaysImpl(localeSorted, format, index, 'weekdaysMin');
    }

    getSetGlobalLocale('en', {
        eras: [
            {
                since: '0001-01-01',
                until: +Infinity,
                offset: 1,
                name: 'Anno Domini',
                narrow: 'AD',
                abbr: 'AD',
            },
            {
                since: '0000-12-31',
                until: -Infinity,
                offset: 1,
                name: 'Before Christ',
                narrow: 'BC',
                abbr: 'BC',
            },
        ],
        dayOfMonthOrdinalParse: /\d{1,2}(th|st|nd|rd)/,
        ordinal: function (number) {
            var b = number % 10,
                output =
                    toInt((number % 100) / 10) === 1
                        ? 'th'
                        : b === 1
                        ? 'st'
                        : b === 2
                        ? 'nd'
                        : b === 3
                        ? 'rd'
                        : 'th';
            return number + output;
        },
    });

    // Side effect imports

    hooks.lang = deprecate(
        'moment.lang is deprecated. Use moment.locale instead.',
        getSetGlobalLocale
    );
    hooks.langData = deprecate(
        'moment.langData is deprecated. Use moment.localeData instead.',
        getLocale
    );

    var mathAbs = Math.abs;

    function abs() {
        var data = this._data;

        this._milliseconds = mathAbs(this._milliseconds);
        this._days = mathAbs(this._days);
        this._months = mathAbs(this._months);

        data.milliseconds = mathAbs(data.milliseconds);
        data.seconds = mathAbs(data.seconds);
        data.minutes = mathAbs(data.minutes);
        data.hours = mathAbs(data.hours);
        data.months = mathAbs(data.months);
        data.years = mathAbs(data.years);

        return this;
    }

    function addSubtract$1(duration, input, value, direction) {
        var other = createDuration(input, value);

        duration._milliseconds += direction * other._milliseconds;
        duration._days += direction * other._days;
        duration._months += direction * other._months;

        return duration._bubble();
    }

    // supports only 2.0-style add(1, 's') or add(duration)
    function add$1(input, value) {
        return addSubtract$1(this, input, value, 1);
    }

    // supports only 2.0-style subtract(1, 's') or subtract(duration)
    function subtract$1(input, value) {
        return addSubtract$1(this, input, value, -1);
    }

    function absCeil(number) {
        if (number < 0) {
            return Math.floor(number);
        } else {
            return Math.ceil(number);
        }
    }

    function bubble() {
        var milliseconds = this._milliseconds,
            days = this._days,
            months = this._months,
            data = this._data,
            seconds,
            minutes,
            hours,
            years,
            monthsFromDays;

        // if we have a mix of positive and negative values, bubble down first
        // check: https://github.com/moment/moment/issues/2166
        if (
            !(
                (milliseconds >= 0 && days >= 0 && months >= 0) ||
                (milliseconds <= 0 && days <= 0 && months <= 0)
            )
        ) {
            milliseconds += absCeil(monthsToDays(months) + days) * 864e5;
            days = 0;
            months = 0;
        }

        // The following code bubbles up values, see the tests for
        // examples of what that means.
        data.milliseconds = milliseconds % 1000;

        seconds = absFloor(milliseconds / 1000);
        data.seconds = seconds % 60;

        minutes = absFloor(seconds / 60);
        data.minutes = minutes % 60;

        hours = absFloor(minutes / 60);
        data.hours = hours % 24;

        days += absFloor(hours / 24);

        // convert days to months
        monthsFromDays = absFloor(daysToMonths(days));
        months += monthsFromDays;
        days -= absCeil(monthsToDays(monthsFromDays));

        // 12 months -> 1 year
        years = absFloor(months / 12);
        months %= 12;

        data.days = days;
        data.months = months;
        data.years = years;

        return this;
    }

    function daysToMonths(days) {
        // 400 years have 146097 days (taking into account leap year rules)
        // 400 years have 12 months === 4800
        return (days * 4800) / 146097;
    }

    function monthsToDays(months) {
        // the reverse of daysToMonths
        return (months * 146097) / 4800;
    }

    function as(units) {
        if (!this.isValid()) {
            return NaN;
        }
        var days,
            months,
            milliseconds = this._milliseconds;

        units = normalizeUnits(units);

        if (units === 'month' || units === 'quarter' || units === 'year') {
            days = this._days + milliseconds / 864e5;
            months = this._months + daysToMonths(days);
            switch (units) {
                case 'month':
                    return months;
                case 'quarter':
                    return months / 3;
                case 'year':
                    return months / 12;
            }
        } else {
            // handle milliseconds separately because of floating point math errors (issue #1867)
            days = this._days + Math.round(monthsToDays(this._months));
            switch (units) {
                case 'week':
                    return days / 7 + milliseconds / 6048e5;
                case 'day':
                    return days + milliseconds / 864e5;
                case 'hour':
                    return days * 24 + milliseconds / 36e5;
                case 'minute':
                    return days * 1440 + milliseconds / 6e4;
                case 'second':
                    return days * 86400 + milliseconds / 1000;
                // Math.floor prevents floating point math errors here
                case 'millisecond':
                    return Math.floor(days * 864e5) + milliseconds;
                default:
                    throw new Error('Unknown unit ' + units);
            }
        }
    }

    // TODO: Use this.as('ms')?
    function valueOf$1() {
        if (!this.isValid()) {
            return NaN;
        }
        return (
            this._milliseconds +
            this._days * 864e5 +
            (this._months % 12) * 2592e6 +
            toInt(this._months / 12) * 31536e6
        );
    }

    function makeAs(alias) {
        return function () {
            return this.as(alias);
        };
    }

    var asMilliseconds = makeAs('ms'),
        asSeconds = makeAs('s'),
        asMinutes = makeAs('m'),
        asHours = makeAs('h'),
        asDays = makeAs('d'),
        asWeeks = makeAs('w'),
        asMonths = makeAs('M'),
        asQuarters = makeAs('Q'),
        asYears = makeAs('y');

    function clone$1() {
        return createDuration(this);
    }

    function get$2(units) {
        units = normalizeUnits(units);
        return this.isValid() ? this[units + 's']() : NaN;
    }

    function makeGetter(name) {
        return function () {
            return this.isValid() ? this._data[name] : NaN;
        };
    }

    var milliseconds = makeGetter('milliseconds'),
        seconds = makeGetter('seconds'),
        minutes = makeGetter('minutes'),
        hours = makeGetter('hours'),
        days = makeGetter('days'),
        months = makeGetter('months'),
        years = makeGetter('years');

    function weeks() {
        return absFloor(this.days() / 7);
    }

    var round = Math.round,
        thresholds = {
            ss: 44, // a few seconds to seconds
            s: 45, // seconds to minute
            m: 45, // minutes to hour
            h: 22, // hours to day
            d: 26, // days to month/week
            w: null, // weeks to month
            M: 11, // months to year
        };

    // helper function for moment.fn.from, moment.fn.fromNow, and moment.duration.fn.humanize
    function substituteTimeAgo(string, number, withoutSuffix, isFuture, locale) {
        return locale.relativeTime(number || 1, !!withoutSuffix, string, isFuture);
    }

    function relativeTime$1(posNegDuration, withoutSuffix, thresholds, locale) {
        var duration = createDuration(posNegDuration).abs(),
            seconds = round(duration.as('s')),
            minutes = round(duration.as('m')),
            hours = round(duration.as('h')),
            days = round(duration.as('d')),
            months = round(duration.as('M')),
            weeks = round(duration.as('w')),
            years = round(duration.as('y')),
            a =
                (seconds <= thresholds.ss && ['s', seconds]) ||
                (seconds < thresholds.s && ['ss', seconds]) ||
                (minutes <= 1 && ['m']) ||
                (minutes < thresholds.m && ['mm', minutes]) ||
                (hours <= 1 && ['h']) ||
                (hours < thresholds.h && ['hh', hours]) ||
                (days <= 1 && ['d']) ||
                (days < thresholds.d && ['dd', days]);

        if (thresholds.w != null) {
            a =
                a ||
                (weeks <= 1 && ['w']) ||
                (weeks < thresholds.w && ['ww', weeks]);
        }
        a = a ||
            (months <= 1 && ['M']) ||
            (months < thresholds.M && ['MM', months]) ||
            (years <= 1 && ['y']) || ['yy', years];

        a[2] = withoutSuffix;
        a[3] = +posNegDuration > 0;
        a[4] = locale;
        return substituteTimeAgo.apply(null, a);
    }

    // This function allows you to set the rounding function for relative time strings
    function getSetRelativeTimeRounding(roundingFunction) {
        if (roundingFunction === undefined) {
            return round;
        }
        if (typeof roundingFunction === 'function') {
            round = roundingFunction;
            return true;
        }
        return false;
    }

    // This function allows you to set a threshold for relative time strings
    function getSetRelativeTimeThreshold(threshold, limit) {
        if (thresholds[threshold] === undefined) {
            return false;
        }
        if (limit === undefined) {
            return thresholds[threshold];
        }
        thresholds[threshold] = limit;
        if (threshold === 's') {
            thresholds.ss = limit - 1;
        }
        return true;
    }

    function humanize(argWithSuffix, argThresholds) {
        if (!this.isValid()) {
            return this.localeData().invalidDate();
        }

        var withSuffix = false,
            th = thresholds,
            locale,
            output;

        if (typeof argWithSuffix === 'object') {
            argThresholds = argWithSuffix;
            argWithSuffix = false;
        }
        if (typeof argWithSuffix === 'boolean') {
            withSuffix = argWithSuffix;
        }
        if (typeof argThresholds === 'object') {
            th = Object.assign({}, thresholds, argThresholds);
            if (argThresholds.s != null && argThresholds.ss == null) {
                th.ss = argThresholds.s - 1;
            }
        }

        locale = this.localeData();
        output = relativeTime$1(this, !withSuffix, th, locale);

        if (withSuffix) {
            output = locale.pastFuture(+this, output);
        }

        return locale.postformat(output);
    }

    var abs$1 = Math.abs;

    function sign(x) {
        return (x > 0) - (x < 0) || +x;
    }

    function toISOString$1() {
        // for ISO strings we do not use the normal bubbling rules:
        //  * milliseconds bubble up until they become hours
        //  * days do not bubble at all
        //  * months bubble up until they become years
        // This is because there is no context-free conversion between hours and days
        // (think of clock changes)
        // and also not between days and months (28-31 days per month)
        if (!this.isValid()) {
            return this.localeData().invalidDate();
        }

        var seconds = abs$1(this._milliseconds) / 1000,
            days = abs$1(this._days),
            months = abs$1(this._months),
            minutes,
            hours,
            years,
            s,
            total = this.asSeconds(),
            totalSign,
            ymSign,
            daysSign,
            hmsSign;

        if (!total) {
            // this is the same as C#'s (Noda) and python (isodate)...
            // but not other JS (goog.date)
            return 'P0D';
        }

        // 3600 seconds -> 60 minutes -> 1 hour
        minutes = absFloor(seconds / 60);
        hours = absFloor(minutes / 60);
        seconds %= 60;
        minutes %= 60;

        // 12 months -> 1 year
        years = absFloor(months / 12);
        months %= 12;

        // inspired by https://github.com/dordille/moment-isoduration/blob/master/moment.isoduration.js
        s = seconds ? seconds.toFixed(3).replace(/\.?0+$/, '') : '';

        totalSign = total < 0 ? '-' : '';
        ymSign = sign(this._months) !== sign(total) ? '-' : '';
        daysSign = sign(this._days) !== sign(total) ? '-' : '';
        hmsSign = sign(this._milliseconds) !== sign(total) ? '-' : '';

        return (
            totalSign +
            'P' +
            (years ? ymSign + years + 'Y' : '') +
            (months ? ymSign + months + 'M' : '') +
            (days ? daysSign + days + 'D' : '') +
            (hours || minutes || seconds ? 'T' : '') +
            (hours ? hmsSign + hours + 'H' : '') +
            (minutes ? hmsSign + minutes + 'M' : '') +
            (seconds ? hmsSign + s + 'S' : '')
        );
    }

    var proto$2 = Duration.prototype;

    proto$2.isValid = isValid$1;
    proto$2.abs = abs;
    proto$2.add = add$1;
    proto$2.subtract = subtract$1;
    proto$2.as = as;
    proto$2.asMilliseconds = asMilliseconds;
    proto$2.asSeconds = asSeconds;
    proto$2.asMinutes = asMinutes;
    proto$2.asHours = asHours;
    proto$2.asDays = asDays;
    proto$2.asWeeks = asWeeks;
    proto$2.asMonths = asMonths;
    proto$2.asQuarters = asQuarters;
    proto$2.asYears = asYears;
    proto$2.valueOf = valueOf$1;
    proto$2._bubble = bubble;
    proto$2.clone = clone$1;
    proto$2.get = get$2;
    proto$2.milliseconds = milliseconds;
    proto$2.seconds = seconds;
    proto$2.minutes = minutes;
    proto$2.hours = hours;
    proto$2.days = days;
    proto$2.weeks = weeks;
    proto$2.months = months;
    proto$2.years = years;
    proto$2.humanize = humanize;
    proto$2.toISOString = toISOString$1;
    proto$2.toString = toISOString$1;
    proto$2.toJSON = toISOString$1;
    proto$2.locale = locale;
    proto$2.localeData = localeData;

    proto$2.toIsoString = deprecate(
        'toIsoString() is deprecated. Please use toISOString() instead (notice the capitals)',
        toISOString$1
    );
    proto$2.lang = lang;

    // FORMATTING

    addFormatToken('X', 0, 0, 'unix');
    addFormatToken('x', 0, 0, 'valueOf');

    // PARSING

    addRegexToken('x', matchSigned);
    addRegexToken('X', matchTimestamp);
    addParseToken('X', function (input, array, config) {
        config._d = new Date(parseFloat(input) * 1000);
    });
    addParseToken('x', function (input, array, config) {
        config._d = new Date(toInt(input));
    });

    //! moment.js

    hooks.version = '2.29.1';

    setHookCallback(createLocal);

    hooks.fn = proto;
    hooks.min = min;
    hooks.max = max;
    hooks.now = now;
    hooks.utc = createUTC;
    hooks.unix = createUnix;
    hooks.months = listMonths;
    hooks.isDate = isDate;
    hooks.locale = getSetGlobalLocale;
    hooks.invalid = createInvalid;
    hooks.duration = createDuration;
    hooks.isMoment = isMoment;
    hooks.weekdays = listWeekdays;
    hooks.parseZone = createInZone;
    hooks.localeData = getLocale;
    hooks.isDuration = isDuration;
    hooks.monthsShort = listMonthsShort;
    hooks.weekdaysMin = listWeekdaysMin;
    hooks.defineLocale = defineLocale;
    hooks.updateLocale = updateLocale;
    hooks.locales = listLocales;
    hooks.weekdaysShort = listWeekdaysShort;
    hooks.normalizeUnits = normalizeUnits;
    hooks.relativeTimeRounding = getSetRelativeTimeRounding;
    hooks.relativeTimeThreshold = getSetRelativeTimeThreshold;
    hooks.calendarFormat = getCalendarFormat;
    hooks.prototype = proto;

    // currently HTML5 input type only supports 24-hour formats
    hooks.HTML5_FMT = {
        DATETIME_LOCAL: 'YYYY-MM-DDTHH:mm', // <input type="datetime-local" />
        DATETIME_LOCAL_SECONDS: 'YYYY-MM-DDTHH:mm:ss', // <input type="datetime-local" step="1" />
        DATETIME_LOCAL_MS: 'YYYY-MM-DDTHH:mm:ss.SSS', // <input type="datetime-local" step="0.001" />
        DATE: 'YYYY-MM-DD', // <input type="date" />
        TIME: 'HH:mm', // <input type="time" />
        TIME_SECONDS: 'HH:mm:ss', // <input type="time" step="1" />
        TIME_MS: 'HH:mm:ss.SSS', // <input type="time" step="0.001" />
        WEEK: 'GGGG-[W]WW', // <input type="week" />
        MONTH: 'YYYY-MM', // <input type="month" />
    };

    return hooks;

})));
});

var componentEmitter = createCommonjsModule(function (module) {
/**
 * Expose `Emitter`.
 */

{
  module.exports = Emitter;
}

/**
 * Initialize a new `Emitter`.
 *
 * @api public
 */

function Emitter(obj) {
  if (obj) return mixin(obj);
}
/**
 * Mixin the emitter properties.
 *
 * @param {Object} obj
 * @return {Object}
 * @api private
 */

function mixin(obj) {
  for (var key in Emitter.prototype) {
    obj[key] = Emitter.prototype[key];
  }
  return obj;
}

/**
 * Listen on the given `event` with `fn`.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.on =
Emitter.prototype.addEventListener = function(event, fn){
  this._callbacks = this._callbacks || {};
  (this._callbacks['$' + event] = this._callbacks['$' + event] || [])
    .push(fn);
  return this;
};

/**
 * Adds an `event` listener that will be invoked a single
 * time then automatically removed.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.once = function(event, fn){
  function on() {
    this.off(event, on);
    fn.apply(this, arguments);
  }

  on.fn = fn;
  this.on(event, on);
  return this;
};

/**
 * Remove the given callback for `event` or all
 * registered callbacks.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.off =
Emitter.prototype.removeListener =
Emitter.prototype.removeAllListeners =
Emitter.prototype.removeEventListener = function(event, fn){
  this._callbacks = this._callbacks || {};

  // all
  if (0 == arguments.length) {
    this._callbacks = {};
    return this;
  }

  // specific event
  var callbacks = this._callbacks['$' + event];
  if (!callbacks) return this;

  // remove all handlers
  if (1 == arguments.length) {
    delete this._callbacks['$' + event];
    return this;
  }

  // remove specific handler
  var cb;
  for (var i = 0; i < callbacks.length; i++) {
    cb = callbacks[i];
    if (cb === fn || cb.fn === fn) {
      callbacks.splice(i, 1);
      break;
    }
  }

  // Remove event specific arrays for event types that no
  // one is subscribed for to avoid memory leak.
  if (callbacks.length === 0) {
    delete this._callbacks['$' + event];
  }

  return this;
};

/**
 * Emit `event` with the given args.
 *
 * @param {String} event
 * @param {Mixed} ...
 * @return {Emitter}
 */

Emitter.prototype.emit = function(event){
  this._callbacks = this._callbacks || {};

  var args = new Array(arguments.length - 1)
    , callbacks = this._callbacks['$' + event];

  for (var i = 1; i < arguments.length; i++) {
    args[i - 1] = arguments[i];
  }

  if (callbacks) {
    callbacks = callbacks.slice(0);
    for (var i = 0, len = callbacks.length; i < len; ++i) {
      callbacks[i].apply(this, args);
    }
  }

  return this;
};

/**
 * Return array of callbacks for `event`.
 *
 * @param {String} event
 * @return {Array}
 * @api public
 */

Emitter.prototype.listeners = function(event){
  this._callbacks = this._callbacks || {};
  return this._callbacks['$' + event] || [];
};

/**
 * Check if this emitter has `event` handlers.
 *
 * @param {String} event
 * @return {Boolean}
 * @api public
 */

Emitter.prototype.hasListeners = function(event){
  return !! this.listeners(event).length;
};
});

/*! Hammer.JS - v2.0.17-rc - 2019-12-16
 * http://naver.github.io/egjs
 *
 * Forked By Naver egjs
 * Copyright (c) hammerjs
 * Licensed under the MIT license */
function _extends() {
  _extends = Object.assign || function (target) {
    for (var i = 1; i < arguments.length; i++) {
      var source = arguments[i];

      for (var key in source) {
        if (Object.prototype.hasOwnProperty.call(source, key)) {
          target[key] = source[key];
        }
      }
    }

    return target;
  };

  return _extends.apply(this, arguments);
}

function _inheritsLoose(subClass, superClass) {
  subClass.prototype = Object.create(superClass.prototype);
  subClass.prototype.constructor = subClass;
  subClass.__proto__ = superClass;
}

function _assertThisInitialized(self) {
  if (self === void 0) {
    throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
  }

  return self;
}

/**
 * @private
 * extend object.
 * means that properties in dest will be overwritten by the ones in src.
 * @param {Object} target
 * @param {...Object} objects_to_assign
 * @returns {Object} target
 */
var assign;

if (typeof Object.assign !== 'function') {
  assign = function assign(target) {
    if (target === undefined || target === null) {
      throw new TypeError('Cannot convert undefined or null to object');
    }

    var output = Object(target);

    for (var index = 1; index < arguments.length; index++) {
      var source = arguments[index];

      if (source !== undefined && source !== null) {
        for (var nextKey in source) {
          if (source.hasOwnProperty(nextKey)) {
            output[nextKey] = source[nextKey];
          }
        }
      }
    }

    return output;
  };
} else {
  assign = Object.assign;
}

var assign$1 = assign;

var VENDOR_PREFIXES = ['', 'webkit', 'Moz', 'MS', 'ms', 'o'];
var TEST_ELEMENT = typeof document === "undefined" ? {
  style: {}
} : document.createElement('div');
var TYPE_FUNCTION = 'function';
var round = Math.round,
    abs = Math.abs;
var now = Date.now;

/**
 * @private
 * get the prefixed property
 * @param {Object} obj
 * @param {String} property
 * @returns {String|Undefined} prefixed
 */

function prefixed(obj, property) {
  var prefix;
  var prop;
  var camelProp = property[0].toUpperCase() + property.slice(1);
  var i = 0;

  while (i < VENDOR_PREFIXES.length) {
    prefix = VENDOR_PREFIXES[i];
    prop = prefix ? prefix + camelProp : property;

    if (prop in obj) {
      return prop;
    }

    i++;
  }

  return undefined;
}

/* eslint-disable no-new-func, no-nested-ternary */
var win;

if (typeof window === "undefined") {
  // window is undefined in node.js
  win = {};
} else {
  win = window;
}

var PREFIXED_TOUCH_ACTION = prefixed(TEST_ELEMENT.style, 'touchAction');
var NATIVE_TOUCH_ACTION = PREFIXED_TOUCH_ACTION !== undefined;
function getTouchActionProps() {
  if (!NATIVE_TOUCH_ACTION) {
    return false;
  }

  var touchMap = {};
  var cssSupports = win.CSS && win.CSS.supports;
  ['auto', 'manipulation', 'pan-y', 'pan-x', 'pan-x pan-y', 'none'].forEach(function (val) {
    // If css.supports is not supported but there is native touch-action assume it supports
    // all values. This is the case for IE 10 and 11.
    return touchMap[val] = cssSupports ? win.CSS.supports('touch-action', val) : true;
  });
  return touchMap;
}

var TOUCH_ACTION_COMPUTE = 'compute';
var TOUCH_ACTION_AUTO = 'auto';
var TOUCH_ACTION_MANIPULATION = 'manipulation'; // not implemented

var TOUCH_ACTION_NONE = 'none';
var TOUCH_ACTION_PAN_X = 'pan-x';
var TOUCH_ACTION_PAN_Y = 'pan-y';
var TOUCH_ACTION_MAP = getTouchActionProps();

var MOBILE_REGEX = /mobile|tablet|ip(ad|hone|od)|android/i;
var SUPPORT_TOUCH = 'ontouchstart' in win;
var SUPPORT_POINTER_EVENTS = prefixed(win, 'PointerEvent') !== undefined;
var SUPPORT_ONLY_TOUCH = SUPPORT_TOUCH && MOBILE_REGEX.test(navigator.userAgent);
var INPUT_TYPE_TOUCH = 'touch';
var INPUT_TYPE_PEN = 'pen';
var INPUT_TYPE_MOUSE = 'mouse';
var INPUT_TYPE_KINECT = 'kinect';
var COMPUTE_INTERVAL = 25;
var INPUT_START = 1;
var INPUT_MOVE = 2;
var INPUT_END = 4;
var INPUT_CANCEL = 8;
var DIRECTION_NONE = 1;
var DIRECTION_LEFT = 2;
var DIRECTION_RIGHT = 4;
var DIRECTION_UP = 8;
var DIRECTION_DOWN = 16;
var DIRECTION_HORIZONTAL = DIRECTION_LEFT | DIRECTION_RIGHT;
var DIRECTION_VERTICAL = DIRECTION_UP | DIRECTION_DOWN;
var DIRECTION_ALL = DIRECTION_HORIZONTAL | DIRECTION_VERTICAL;
var PROPS_XY = ['x', 'y'];
var PROPS_CLIENT_XY = ['clientX', 'clientY'];

/**
 * @private
 * walk objects and arrays
 * @param {Object} obj
 * @param {Function} iterator
 * @param {Object} context
 */
function each(obj, iterator, context) {
  var i;

  if (!obj) {
    return;
  }

  if (obj.forEach) {
    obj.forEach(iterator, context);
  } else if (obj.length !== undefined) {
    i = 0;

    while (i < obj.length) {
      iterator.call(context, obj[i], i, obj);
      i++;
    }
  } else {
    for (i in obj) {
      obj.hasOwnProperty(i) && iterator.call(context, obj[i], i, obj);
    }
  }
}

/**
 * @private
 * let a boolean value also be a function that must return a boolean
 * this first item in args will be used as the context
 * @param {Boolean|Function} val
 * @param {Array} [args]
 * @returns {Boolean}
 */

function boolOrFn(val, args) {
  if (typeof val === TYPE_FUNCTION) {
    return val.apply(args ? args[0] || undefined : undefined, args);
  }

  return val;
}

/**
 * @private
 * small indexOf wrapper
 * @param {String} str
 * @param {String} find
 * @returns {Boolean} found
 */
function inStr(str, find) {
  return str.indexOf(find) > -1;
}

/**
 * @private
 * when the touchActions are collected they are not a valid value, so we need to clean things up. *
 * @param {String} actions
 * @returns {*}
 */

function cleanTouchActions(actions) {
  // none
  if (inStr(actions, TOUCH_ACTION_NONE)) {
    return TOUCH_ACTION_NONE;
  }

  var hasPanX = inStr(actions, TOUCH_ACTION_PAN_X);
  var hasPanY = inStr(actions, TOUCH_ACTION_PAN_Y); // if both pan-x and pan-y are set (different recognizers
  // for different directions, e.g. horizontal pan but vertical swipe?)
  // we need none (as otherwise with pan-x pan-y combined none of these
  // recognizers will work, since the browser would handle all panning

  if (hasPanX && hasPanY) {
    return TOUCH_ACTION_NONE;
  } // pan-x OR pan-y


  if (hasPanX || hasPanY) {
    return hasPanX ? TOUCH_ACTION_PAN_X : TOUCH_ACTION_PAN_Y;
  } // manipulation


  if (inStr(actions, TOUCH_ACTION_MANIPULATION)) {
    return TOUCH_ACTION_MANIPULATION;
  }

  return TOUCH_ACTION_AUTO;
}

/**
 * @private
 * Touch Action
 * sets the touchAction property or uses the js alternative
 * @param {Manager} manager
 * @param {String} value
 * @constructor
 */

var TouchAction =
/*#__PURE__*/
function () {
  function TouchAction(manager, value) {
    this.manager = manager;
    this.set(value);
  }
  /**
   * @private
   * set the touchAction value on the element or enable the polyfill
   * @param {String} value
   */


  var _proto = TouchAction.prototype;

  _proto.set = function set(value) {
    // find out the touch-action by the event handlers
    if (value === TOUCH_ACTION_COMPUTE) {
      value = this.compute();
    }

    if (NATIVE_TOUCH_ACTION && this.manager.element.style && TOUCH_ACTION_MAP[value]) {
      this.manager.element.style[PREFIXED_TOUCH_ACTION] = value;
    }

    this.actions = value.toLowerCase().trim();
  };
  /**
   * @private
   * just re-set the touchAction value
   */


  _proto.update = function update() {
    this.set(this.manager.options.touchAction);
  };
  /**
   * @private
   * compute the value for the touchAction property based on the recognizer's settings
   * @returns {String} value
   */


  _proto.compute = function compute() {
    var actions = [];
    each(this.manager.recognizers, function (recognizer) {
      if (boolOrFn(recognizer.options.enable, [recognizer])) {
        actions = actions.concat(recognizer.getTouchAction());
      }
    });
    return cleanTouchActions(actions.join(' '));
  };
  /**
   * @private
   * this method is called on each input cycle and provides the preventing of the browser behavior
   * @param {Object} input
   */


  _proto.preventDefaults = function preventDefaults(input) {
    var srcEvent = input.srcEvent;
    var direction = input.offsetDirection; // if the touch action did prevented once this session

    if (this.manager.session.prevented) {
      srcEvent.preventDefault();
      return;
    }

    var actions = this.actions;
    var hasNone = inStr(actions, TOUCH_ACTION_NONE) && !TOUCH_ACTION_MAP[TOUCH_ACTION_NONE];
    var hasPanY = inStr(actions, TOUCH_ACTION_PAN_Y) && !TOUCH_ACTION_MAP[TOUCH_ACTION_PAN_Y];
    var hasPanX = inStr(actions, TOUCH_ACTION_PAN_X) && !TOUCH_ACTION_MAP[TOUCH_ACTION_PAN_X];

    if (hasNone) {
      // do not prevent defaults if this is a tap gesture
      var isTapPointer = input.pointers.length === 1;
      var isTapMovement = input.distance < 2;
      var isTapTouchTime = input.deltaTime < 250;

      if (isTapPointer && isTapMovement && isTapTouchTime) {
        return;
      }
    }

    if (hasPanX && hasPanY) {
      // `pan-x pan-y` means browser handles all scrolling/panning, do not prevent
      return;
    }

    if (hasNone || hasPanY && direction & DIRECTION_HORIZONTAL || hasPanX && direction & DIRECTION_VERTICAL) {
      return this.preventSrc(srcEvent);
    }
  };
  /**
   * @private
   * call preventDefault to prevent the browser's default behavior (scrolling in most cases)
   * @param {Object} srcEvent
   */


  _proto.preventSrc = function preventSrc(srcEvent) {
    this.manager.session.prevented = true;
    srcEvent.preventDefault();
  };

  return TouchAction;
}();

/**
 * @private
 * find if a node is in the given parent
 * @method hasParent
 * @param {HTMLElement} node
 * @param {HTMLElement} parent
 * @return {Boolean} found
 */
function hasParent(node, parent) {
  while (node) {
    if (node === parent) {
      return true;
    }

    node = node.parentNode;
  }

  return false;
}

/**
 * @private
 * get the center of all the pointers
 * @param {Array} pointers
 * @return {Object} center contains `x` and `y` properties
 */

function getCenter(pointers) {
  var pointersLength = pointers.length; // no need to loop when only one touch

  if (pointersLength === 1) {
    return {
      x: round(pointers[0].clientX),
      y: round(pointers[0].clientY)
    };
  }

  var x = 0;
  var y = 0;
  var i = 0;

  while (i < pointersLength) {
    x += pointers[i].clientX;
    y += pointers[i].clientY;
    i++;
  }

  return {
    x: round(x / pointersLength),
    y: round(y / pointersLength)
  };
}

/**
 * @private
 * create a simple clone from the input used for storage of firstInput and firstMultiple
 * @param {Object} input
 * @returns {Object} clonedInputData
 */

function simpleCloneInputData(input) {
  // make a simple copy of the pointers because we will get a reference if we don't
  // we only need clientXY for the calculations
  var pointers = [];
  var i = 0;

  while (i < input.pointers.length) {
    pointers[i] = {
      clientX: round(input.pointers[i].clientX),
      clientY: round(input.pointers[i].clientY)
    };
    i++;
  }

  return {
    timeStamp: now(),
    pointers: pointers,
    center: getCenter(pointers),
    deltaX: input.deltaX,
    deltaY: input.deltaY
  };
}

/**
 * @private
 * calculate the absolute distance between two points
 * @param {Object} p1 {x, y}
 * @param {Object} p2 {x, y}
 * @param {Array} [props] containing x and y keys
 * @return {Number} distance
 */

function getDistance(p1, p2, props) {
  if (!props) {
    props = PROPS_XY;
  }

  var x = p2[props[0]] - p1[props[0]];
  var y = p2[props[1]] - p1[props[1]];
  return Math.sqrt(x * x + y * y);
}

/**
 * @private
 * calculate the angle between two coordinates
 * @param {Object} p1
 * @param {Object} p2
 * @param {Array} [props] containing x and y keys
 * @return {Number} angle
 */

function getAngle(p1, p2, props) {
  if (!props) {
    props = PROPS_XY;
  }

  var x = p2[props[0]] - p1[props[0]];
  var y = p2[props[1]] - p1[props[1]];
  return Math.atan2(y, x) * 180 / Math.PI;
}

/**
 * @private
 * get the direction between two points
 * @param {Number} x
 * @param {Number} y
 * @return {Number} direction
 */

function getDirection(x, y) {
  if (x === y) {
    return DIRECTION_NONE;
  }

  if (abs(x) >= abs(y)) {
    return x < 0 ? DIRECTION_LEFT : DIRECTION_RIGHT;
  }

  return y < 0 ? DIRECTION_UP : DIRECTION_DOWN;
}

function computeDeltaXY(session, input) {
  var center = input.center; // let { offsetDelta:offset = {}, prevDelta = {}, prevInput = {} } = session;
  // jscs throwing error on defalut destructured values and without defaults tests fail

  var offset = session.offsetDelta || {};
  var prevDelta = session.prevDelta || {};
  var prevInput = session.prevInput || {};

  if (input.eventType === INPUT_START || prevInput.eventType === INPUT_END) {
    prevDelta = session.prevDelta = {
      x: prevInput.deltaX || 0,
      y: prevInput.deltaY || 0
    };
    offset = session.offsetDelta = {
      x: center.x,
      y: center.y
    };
  }

  input.deltaX = prevDelta.x + (center.x - offset.x);
  input.deltaY = prevDelta.y + (center.y - offset.y);
}

/**
 * @private
 * calculate the velocity between two points. unit is in px per ms.
 * @param {Number} deltaTime
 * @param {Number} x
 * @param {Number} y
 * @return {Object} velocity `x` and `y`
 */
function getVelocity(deltaTime, x, y) {
  return {
    x: x / deltaTime || 0,
    y: y / deltaTime || 0
  };
}

/**
 * @private
 * calculate the scale factor between two pointersets
 * no scale is 1, and goes down to 0 when pinched together, and bigger when pinched out
 * @param {Array} start array of pointers
 * @param {Array} end array of pointers
 * @return {Number} scale
 */

function getScale(start, end) {
  return getDistance(end[0], end[1], PROPS_CLIENT_XY) / getDistance(start[0], start[1], PROPS_CLIENT_XY);
}

/**
 * @private
 * calculate the rotation degrees between two pointersets
 * @param {Array} start array of pointers
 * @param {Array} end array of pointers
 * @return {Number} rotation
 */

function getRotation(start, end) {
  return getAngle(end[1], end[0], PROPS_CLIENT_XY) + getAngle(start[1], start[0], PROPS_CLIENT_XY);
}

/**
 * @private
 * velocity is calculated every x ms
 * @param {Object} session
 * @param {Object} input
 */

function computeIntervalInputData(session, input) {
  var last = session.lastInterval || input;
  var deltaTime = input.timeStamp - last.timeStamp;
  var velocity;
  var velocityX;
  var velocityY;
  var direction;

  if (input.eventType !== INPUT_CANCEL && (deltaTime > COMPUTE_INTERVAL || last.velocity === undefined)) {
    var deltaX = input.deltaX - last.deltaX;
    var deltaY = input.deltaY - last.deltaY;
    var v = getVelocity(deltaTime, deltaX, deltaY);
    velocityX = v.x;
    velocityY = v.y;
    velocity = abs(v.x) > abs(v.y) ? v.x : v.y;
    direction = getDirection(deltaX, deltaY);
    session.lastInterval = input;
  } else {
    // use latest velocity info if it doesn't overtake a minimum period
    velocity = last.velocity;
    velocityX = last.velocityX;
    velocityY = last.velocityY;
    direction = last.direction;
  }

  input.velocity = velocity;
  input.velocityX = velocityX;
  input.velocityY = velocityY;
  input.direction = direction;
}

/**
* @private
 * extend the data with some usable properties like scale, rotate, velocity etc
 * @param {Object} manager
 * @param {Object} input
 */

function computeInputData(manager, input) {
  var session = manager.session;
  var pointers = input.pointers;
  var pointersLength = pointers.length; // store the first input to calculate the distance and direction

  if (!session.firstInput) {
    session.firstInput = simpleCloneInputData(input);
  } // to compute scale and rotation we need to store the multiple touches


  if (pointersLength > 1 && !session.firstMultiple) {
    session.firstMultiple = simpleCloneInputData(input);
  } else if (pointersLength === 1) {
    session.firstMultiple = false;
  }

  var firstInput = session.firstInput,
      firstMultiple = session.firstMultiple;
  var offsetCenter = firstMultiple ? firstMultiple.center : firstInput.center;
  var center = input.center = getCenter(pointers);
  input.timeStamp = now();
  input.deltaTime = input.timeStamp - firstInput.timeStamp;
  input.angle = getAngle(offsetCenter, center);
  input.distance = getDistance(offsetCenter, center);
  computeDeltaXY(session, input);
  input.offsetDirection = getDirection(input.deltaX, input.deltaY);
  var overallVelocity = getVelocity(input.deltaTime, input.deltaX, input.deltaY);
  input.overallVelocityX = overallVelocity.x;
  input.overallVelocityY = overallVelocity.y;
  input.overallVelocity = abs(overallVelocity.x) > abs(overallVelocity.y) ? overallVelocity.x : overallVelocity.y;
  input.scale = firstMultiple ? getScale(firstMultiple.pointers, pointers) : 1;
  input.rotation = firstMultiple ? getRotation(firstMultiple.pointers, pointers) : 0;
  input.maxPointers = !session.prevInput ? input.pointers.length : input.pointers.length > session.prevInput.maxPointers ? input.pointers.length : session.prevInput.maxPointers;
  computeIntervalInputData(session, input); // find the correct target

  var target = manager.element;
  var srcEvent = input.srcEvent;
  var srcEventTarget;

  if (srcEvent.composedPath) {
    srcEventTarget = srcEvent.composedPath()[0];
  } else if (srcEvent.path) {
    srcEventTarget = srcEvent.path[0];
  } else {
    srcEventTarget = srcEvent.target;
  }

  if (hasParent(srcEventTarget, target)) {
    target = srcEventTarget;
  }

  input.target = target;
}

/**
 * @private
 * handle input events
 * @param {Manager} manager
 * @param {String} eventType
 * @param {Object} input
 */

function inputHandler(manager, eventType, input) {
  var pointersLen = input.pointers.length;
  var changedPointersLen = input.changedPointers.length;
  var isFirst = eventType & INPUT_START && pointersLen - changedPointersLen === 0;
  var isFinal = eventType & (INPUT_END | INPUT_CANCEL) && pointersLen - changedPointersLen === 0;
  input.isFirst = !!isFirst;
  input.isFinal = !!isFinal;

  if (isFirst) {
    manager.session = {};
  } // source event is the normalized value of the domEvents
  // like 'touchstart, mouseup, pointerdown'


  input.eventType = eventType; // compute scale, rotation etc

  computeInputData(manager, input); // emit secret event

  manager.emit('hammer.input', input);
  manager.recognize(input);
  manager.session.prevInput = input;
}

/**
 * @private
 * split string on whitespace
 * @param {String} str
 * @returns {Array} words
 */
function splitStr(str) {
  return str.trim().split(/\s+/g);
}

/**
 * @private
 * addEventListener with multiple events at once
 * @param {EventTarget} target
 * @param {String} types
 * @param {Function} handler
 */

function addEventListeners(target, types, handler) {
  each(splitStr(types), function (type) {
    target.addEventListener(type, handler, false);
  });
}

/**
 * @private
 * removeEventListener with multiple events at once
 * @param {EventTarget} target
 * @param {String} types
 * @param {Function} handler
 */

function removeEventListeners(target, types, handler) {
  each(splitStr(types), function (type) {
    target.removeEventListener(type, handler, false);
  });
}

/**
 * @private
 * get the window object of an element
 * @param {HTMLElement} element
 * @returns {DocumentView|Window}
 */
function getWindowForElement(element) {
  var doc = element.ownerDocument || element;
  return doc.defaultView || doc.parentWindow || window;
}

/**
 * @private
 * create new input type manager
 * @param {Manager} manager
 * @param {Function} callback
 * @returns {Input}
 * @constructor
 */

var Input =
/*#__PURE__*/
function () {
  function Input(manager, callback) {
    var self = this;
    this.manager = manager;
    this.callback = callback;
    this.element = manager.element;
    this.target = manager.options.inputTarget; // smaller wrapper around the handler, for the scope and the enabled state of the manager,
    // so when disabled the input events are completely bypassed.

    this.domHandler = function (ev) {
      if (boolOrFn(manager.options.enable, [manager])) {
        self.handler(ev);
      }
    };

    this.init();
  }
  /**
   * @private
   * should handle the inputEvent data and trigger the callback
   * @virtual
   */


  var _proto = Input.prototype;

  _proto.handler = function handler() {};
  /**
   * @private
   * bind the events
   */


  _proto.init = function init() {
    this.evEl && addEventListeners(this.element, this.evEl, this.domHandler);
    this.evTarget && addEventListeners(this.target, this.evTarget, this.domHandler);
    this.evWin && addEventListeners(getWindowForElement(this.element), this.evWin, this.domHandler);
  };
  /**
   * @private
   * unbind the events
   */


  _proto.destroy = function destroy() {
    this.evEl && removeEventListeners(this.element, this.evEl, this.domHandler);
    this.evTarget && removeEventListeners(this.target, this.evTarget, this.domHandler);
    this.evWin && removeEventListeners(getWindowForElement(this.element), this.evWin, this.domHandler);
  };

  return Input;
}();

/**
 * @private
 * find if a array contains the object using indexOf or a simple polyFill
 * @param {Array} src
 * @param {String} find
 * @param {String} [findByKey]
 * @return {Boolean|Number} false when not found, or the index
 */
function inArray(src, find, findByKey) {
  if (src.indexOf && !findByKey) {
    return src.indexOf(find);
  } else {
    var i = 0;

    while (i < src.length) {
      if (findByKey && src[i][findByKey] == find || !findByKey && src[i] === find) {
        // do not use === here, test fails
        return i;
      }

      i++;
    }

    return -1;
  }
}

var POINTER_INPUT_MAP = {
  pointerdown: INPUT_START,
  pointermove: INPUT_MOVE,
  pointerup: INPUT_END,
  pointercancel: INPUT_CANCEL,
  pointerout: INPUT_CANCEL
}; // in IE10 the pointer types is defined as an enum

var IE10_POINTER_TYPE_ENUM = {
  2: INPUT_TYPE_TOUCH,
  3: INPUT_TYPE_PEN,
  4: INPUT_TYPE_MOUSE,
  5: INPUT_TYPE_KINECT // see https://twitter.com/jacobrossi/status/480596438489890816

};
var POINTER_ELEMENT_EVENTS = 'pointerdown';
var POINTER_WINDOW_EVENTS = 'pointermove pointerup pointercancel'; // IE10 has prefixed support, and case-sensitive

if (win.MSPointerEvent && !win.PointerEvent) {
  POINTER_ELEMENT_EVENTS = 'MSPointerDown';
  POINTER_WINDOW_EVENTS = 'MSPointerMove MSPointerUp MSPointerCancel';
}
/**
 * @private
 * Pointer events input
 * @constructor
 * @extends Input
 */


var PointerEventInput =
/*#__PURE__*/
function (_Input) {
  _inheritsLoose(PointerEventInput, _Input);

  function PointerEventInput() {
    var _this;

    var proto = PointerEventInput.prototype;
    proto.evEl = POINTER_ELEMENT_EVENTS;
    proto.evWin = POINTER_WINDOW_EVENTS;
    _this = _Input.apply(this, arguments) || this;
    _this.store = _this.manager.session.pointerEvents = [];
    return _this;
  }
  /**
   * @private
   * handle mouse events
   * @param {Object} ev
   */


  var _proto = PointerEventInput.prototype;

  _proto.handler = function handler(ev) {
    var store = this.store;
    var removePointer = false;
    var eventTypeNormalized = ev.type.toLowerCase().replace('ms', '');
    var eventType = POINTER_INPUT_MAP[eventTypeNormalized];
    var pointerType = IE10_POINTER_TYPE_ENUM[ev.pointerType] || ev.pointerType;
    var isTouch = pointerType === INPUT_TYPE_TOUCH; // get index of the event in the store

    var storeIndex = inArray(store, ev.pointerId, 'pointerId'); // start and mouse must be down

    if (eventType & INPUT_START && (ev.button === 0 || isTouch)) {
      if (storeIndex < 0) {
        store.push(ev);
        storeIndex = store.length - 1;
      }
    } else if (eventType & (INPUT_END | INPUT_CANCEL)) {
      removePointer = true;
    } // it not found, so the pointer hasn't been down (so it's probably a hover)


    if (storeIndex < 0) {
      return;
    } // update the event in the store


    store[storeIndex] = ev;
    this.callback(this.manager, eventType, {
      pointers: store,
      changedPointers: [ev],
      pointerType: pointerType,
      srcEvent: ev
    });

    if (removePointer) {
      // remove from the store
      store.splice(storeIndex, 1);
    }
  };

  return PointerEventInput;
}(Input);

/**
 * @private
 * convert array-like objects to real arrays
 * @param {Object} obj
 * @returns {Array}
 */
function toArray(obj) {
  return Array.prototype.slice.call(obj, 0);
}

/**
 * @private
 * unique array with objects based on a key (like 'id') or just by the array's value
 * @param {Array} src [{id:1},{id:2},{id:1}]
 * @param {String} [key]
 * @param {Boolean} [sort=False]
 * @returns {Array} [{id:1},{id:2}]
 */

function uniqueArray(src, key, sort) {
  var results = [];
  var values = [];
  var i = 0;

  while (i < src.length) {
    var val = key ? src[i][key] : src[i];

    if (inArray(values, val) < 0) {
      results.push(src[i]);
    }

    values[i] = val;
    i++;
  }

  if (sort) {
    if (!key) {
      results = results.sort();
    } else {
      results = results.sort(function (a, b) {
        return a[key] > b[key];
      });
    }
  }

  return results;
}

var TOUCH_INPUT_MAP = {
  touchstart: INPUT_START,
  touchmove: INPUT_MOVE,
  touchend: INPUT_END,
  touchcancel: INPUT_CANCEL
};
var TOUCH_TARGET_EVENTS = 'touchstart touchmove touchend touchcancel';
/**
 * @private
 * Multi-user touch events input
 * @constructor
 * @extends Input
 */

var TouchInput =
/*#__PURE__*/
function (_Input) {
  _inheritsLoose(TouchInput, _Input);

  function TouchInput() {
    var _this;

    TouchInput.prototype.evTarget = TOUCH_TARGET_EVENTS;
    _this = _Input.apply(this, arguments) || this;
    _this.targetIds = {}; // this.evTarget = TOUCH_TARGET_EVENTS;

    return _this;
  }

  var _proto = TouchInput.prototype;

  _proto.handler = function handler(ev) {
    var type = TOUCH_INPUT_MAP[ev.type];
    var touches = getTouches.call(this, ev, type);

    if (!touches) {
      return;
    }

    this.callback(this.manager, type, {
      pointers: touches[0],
      changedPointers: touches[1],
      pointerType: INPUT_TYPE_TOUCH,
      srcEvent: ev
    });
  };

  return TouchInput;
}(Input);

function getTouches(ev, type) {
  var allTouches = toArray(ev.touches);
  var targetIds = this.targetIds; // when there is only one touch, the process can be simplified

  if (type & (INPUT_START | INPUT_MOVE) && allTouches.length === 1) {
    targetIds[allTouches[0].identifier] = true;
    return [allTouches, allTouches];
  }

  var i;
  var targetTouches;
  var changedTouches = toArray(ev.changedTouches);
  var changedTargetTouches = [];
  var target = this.target; // get target touches from touches

  targetTouches = allTouches.filter(function (touch) {
    return hasParent(touch.target, target);
  }); // collect touches

  if (type === INPUT_START) {
    i = 0;

    while (i < targetTouches.length) {
      targetIds[targetTouches[i].identifier] = true;
      i++;
    }
  } // filter changed touches to only contain touches that exist in the collected target ids


  i = 0;

  while (i < changedTouches.length) {
    if (targetIds[changedTouches[i].identifier]) {
      changedTargetTouches.push(changedTouches[i]);
    } // cleanup removed touches


    if (type & (INPUT_END | INPUT_CANCEL)) {
      delete targetIds[changedTouches[i].identifier];
    }

    i++;
  }

  if (!changedTargetTouches.length) {
    return;
  }

  return [// merge targetTouches with changedTargetTouches so it contains ALL touches, including 'end' and 'cancel'
  uniqueArray(targetTouches.concat(changedTargetTouches), 'identifier', true), changedTargetTouches];
}

var MOUSE_INPUT_MAP = {
  mousedown: INPUT_START,
  mousemove: INPUT_MOVE,
  mouseup: INPUT_END
};
var MOUSE_ELEMENT_EVENTS = 'mousedown';
var MOUSE_WINDOW_EVENTS = 'mousemove mouseup';
/**
 * @private
 * Mouse events input
 * @constructor
 * @extends Input
 */

var MouseInput =
/*#__PURE__*/
function (_Input) {
  _inheritsLoose(MouseInput, _Input);

  function MouseInput() {
    var _this;

    var proto = MouseInput.prototype;
    proto.evEl = MOUSE_ELEMENT_EVENTS;
    proto.evWin = MOUSE_WINDOW_EVENTS;
    _this = _Input.apply(this, arguments) || this;
    _this.pressed = false; // mousedown state

    return _this;
  }
  /**
   * @private
   * handle mouse events
   * @param {Object} ev
   */


  var _proto = MouseInput.prototype;

  _proto.handler = function handler(ev) {
    var eventType = MOUSE_INPUT_MAP[ev.type]; // on start we want to have the left mouse button down

    if (eventType & INPUT_START && ev.button === 0) {
      this.pressed = true;
    }

    if (eventType & INPUT_MOVE && ev.which !== 1) {
      eventType = INPUT_END;
    } // mouse must be down


    if (!this.pressed) {
      return;
    }

    if (eventType & INPUT_END) {
      this.pressed = false;
    }

    this.callback(this.manager, eventType, {
      pointers: [ev],
      changedPointers: [ev],
      pointerType: INPUT_TYPE_MOUSE,
      srcEvent: ev
    });
  };

  return MouseInput;
}(Input);

/**
 * @private
 * Combined touch and mouse input
 *
 * Touch has a higher priority then mouse, and while touching no mouse events are allowed.
 * This because touch devices also emit mouse events while doing a touch.
 *
 * @constructor
 * @extends Input
 */

var DEDUP_TIMEOUT = 2500;
var DEDUP_DISTANCE = 25;

function setLastTouch(eventData) {
  var _eventData$changedPoi = eventData.changedPointers,
      touch = _eventData$changedPoi[0];

  if (touch.identifier === this.primaryTouch) {
    var lastTouch = {
      x: touch.clientX,
      y: touch.clientY
    };
    var lts = this.lastTouches;
    this.lastTouches.push(lastTouch);

    var removeLastTouch = function removeLastTouch() {
      var i = lts.indexOf(lastTouch);

      if (i > -1) {
        lts.splice(i, 1);
      }
    };

    setTimeout(removeLastTouch, DEDUP_TIMEOUT);
  }
}

function recordTouches(eventType, eventData) {
  if (eventType & INPUT_START) {
    this.primaryTouch = eventData.changedPointers[0].identifier;
    setLastTouch.call(this, eventData);
  } else if (eventType & (INPUT_END | INPUT_CANCEL)) {
    setLastTouch.call(this, eventData);
  }
}

function isSyntheticEvent(eventData) {
  var x = eventData.srcEvent.clientX;
  var y = eventData.srcEvent.clientY;

  for (var i = 0; i < this.lastTouches.length; i++) {
    var t = this.lastTouches[i];
    var dx = Math.abs(x - t.x);
    var dy = Math.abs(y - t.y);

    if (dx <= DEDUP_DISTANCE && dy <= DEDUP_DISTANCE) {
      return true;
    }
  }

  return false;
}

var TouchMouseInput =
/*#__PURE__*/
function () {
  var TouchMouseInput =
  /*#__PURE__*/
  function (_Input) {
    _inheritsLoose(TouchMouseInput, _Input);

    function TouchMouseInput(_manager, callback) {
      var _this;

      _this = _Input.call(this, _manager, callback) || this;

      _this.handler = function (manager, inputEvent, inputData) {
        var isTouch = inputData.pointerType === INPUT_TYPE_TOUCH;
        var isMouse = inputData.pointerType === INPUT_TYPE_MOUSE;

        if (isMouse && inputData.sourceCapabilities && inputData.sourceCapabilities.firesTouchEvents) {
          return;
        } // when we're in a touch event, record touches to  de-dupe synthetic mouse event


        if (isTouch) {
          recordTouches.call(_assertThisInitialized(_assertThisInitialized(_this)), inputEvent, inputData);
        } else if (isMouse && isSyntheticEvent.call(_assertThisInitialized(_assertThisInitialized(_this)), inputData)) {
          return;
        }

        _this.callback(manager, inputEvent, inputData);
      };

      _this.touch = new TouchInput(_this.manager, _this.handler);
      _this.mouse = new MouseInput(_this.manager, _this.handler);
      _this.primaryTouch = null;
      _this.lastTouches = [];
      return _this;
    }
    /**
     * @private
     * handle mouse and touch events
     * @param {Hammer} manager
     * @param {String} inputEvent
     * @param {Object} inputData
     */


    var _proto = TouchMouseInput.prototype;

    /**
     * @private
     * remove the event listeners
     */
    _proto.destroy = function destroy() {
      this.touch.destroy();
      this.mouse.destroy();
    };

    return TouchMouseInput;
  }(Input);

  return TouchMouseInput;
}();

/**
 * @private
 * create new input type manager
 * called by the Manager constructor
 * @param {Hammer} manager
 * @returns {Input}
 */

function createInputInstance(manager) {
  var Type; // let inputClass = manager.options.inputClass;

  var inputClass = manager.options.inputClass;

  if (inputClass) {
    Type = inputClass;
  } else if (SUPPORT_POINTER_EVENTS) {
    Type = PointerEventInput;
  } else if (SUPPORT_ONLY_TOUCH) {
    Type = TouchInput;
  } else if (!SUPPORT_TOUCH) {
    Type = MouseInput;
  } else {
    Type = TouchMouseInput;
  }

  return new Type(manager, inputHandler);
}

/**
 * @private
 * if the argument is an array, we want to execute the fn on each entry
 * if it aint an array we don't want to do a thing.
 * this is used by all the methods that accept a single and array argument.
 * @param {*|Array} arg
 * @param {String} fn
 * @param {Object} [context]
 * @returns {Boolean}
 */

function invokeArrayArg(arg, fn, context) {
  if (Array.isArray(arg)) {
    each(arg, context[fn], context);
    return true;
  }

  return false;
}

var STATE_POSSIBLE = 1;
var STATE_BEGAN = 2;
var STATE_CHANGED = 4;
var STATE_ENDED = 8;
var STATE_RECOGNIZED = STATE_ENDED;
var STATE_CANCELLED = 16;
var STATE_FAILED = 32;

/**
 * @private
 * get a unique id
 * @returns {number} uniqueId
 */
var _uniqueId = 1;
function uniqueId() {
  return _uniqueId++;
}

/**
 * @private
 * get a recognizer by name if it is bound to a manager
 * @param {Recognizer|String} otherRecognizer
 * @param {Recognizer} recognizer
 * @returns {Recognizer}
 */
function getRecognizerByNameIfManager(otherRecognizer, recognizer) {
  var manager = recognizer.manager;

  if (manager) {
    return manager.get(otherRecognizer);
  }

  return otherRecognizer;
}

/**
 * @private
 * get a usable string, used as event postfix
 * @param {constant} state
 * @returns {String} state
 */

function stateStr(state) {
  if (state & STATE_CANCELLED) {
    return 'cancel';
  } else if (state & STATE_ENDED) {
    return 'end';
  } else if (state & STATE_CHANGED) {
    return 'move';
  } else if (state & STATE_BEGAN) {
    return 'start';
  }

  return '';
}

/**
 * @private
 * Recognizer flow explained; *
 * All recognizers have the initial state of POSSIBLE when a input session starts.
 * The definition of a input session is from the first input until the last input, with all it's movement in it. *
 * Example session for mouse-input: mousedown -> mousemove -> mouseup
 *
 * On each recognizing cycle (see Manager.recognize) the .recognize() method is executed
 * which determines with state it should be.
 *
 * If the recognizer has the state FAILED, CANCELLED or RECOGNIZED (equals ENDED), it is reset to
 * POSSIBLE to give it another change on the next cycle.
 *
 *               Possible
 *                  |
 *            +-----+---------------+
 *            |                     |
 *      +-----+-----+               |
 *      |           |               |
 *   Failed      Cancelled          |
 *                          +-------+------+
 *                          |              |
 *                      Recognized       Began
 *                                         |
 *                                      Changed
 *                                         |
 *                                  Ended/Recognized
 */

/**
 * @private
 * Recognizer
 * Every recognizer needs to extend from this class.
 * @constructor
 * @param {Object} options
 */

var Recognizer =
/*#__PURE__*/
function () {
  function Recognizer(options) {
    if (options === void 0) {
      options = {};
    }

    this.options = _extends({
      enable: true
    }, options);
    this.id = uniqueId();
    this.manager = null; // default is enable true

    this.state = STATE_POSSIBLE;
    this.simultaneous = {};
    this.requireFail = [];
  }
  /**
   * @private
   * set options
   * @param {Object} options
   * @return {Recognizer}
   */


  var _proto = Recognizer.prototype;

  _proto.set = function set(options) {
    assign$1(this.options, options); // also update the touchAction, in case something changed about the directions/enabled state

    this.manager && this.manager.touchAction.update();
    return this;
  };
  /**
   * @private
   * recognize simultaneous with an other recognizer.
   * @param {Recognizer} otherRecognizer
   * @returns {Recognizer} this
   */


  _proto.recognizeWith = function recognizeWith(otherRecognizer) {
    if (invokeArrayArg(otherRecognizer, 'recognizeWith', this)) {
      return this;
    }

    var simultaneous = this.simultaneous;
    otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);

    if (!simultaneous[otherRecognizer.id]) {
      simultaneous[otherRecognizer.id] = otherRecognizer;
      otherRecognizer.recognizeWith(this);
    }

    return this;
  };
  /**
   * @private
   * drop the simultaneous link. it doesnt remove the link on the other recognizer.
   * @param {Recognizer} otherRecognizer
   * @returns {Recognizer} this
   */


  _proto.dropRecognizeWith = function dropRecognizeWith(otherRecognizer) {
    if (invokeArrayArg(otherRecognizer, 'dropRecognizeWith', this)) {
      return this;
    }

    otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);
    delete this.simultaneous[otherRecognizer.id];
    return this;
  };
  /**
   * @private
   * recognizer can only run when an other is failing
   * @param {Recognizer} otherRecognizer
   * @returns {Recognizer} this
   */


  _proto.requireFailure = function requireFailure(otherRecognizer) {
    if (invokeArrayArg(otherRecognizer, 'requireFailure', this)) {
      return this;
    }

    var requireFail = this.requireFail;
    otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);

    if (inArray(requireFail, otherRecognizer) === -1) {
      requireFail.push(otherRecognizer);
      otherRecognizer.requireFailure(this);
    }

    return this;
  };
  /**
   * @private
   * drop the requireFailure link. it does not remove the link on the other recognizer.
   * @param {Recognizer} otherRecognizer
   * @returns {Recognizer} this
   */


  _proto.dropRequireFailure = function dropRequireFailure(otherRecognizer) {
    if (invokeArrayArg(otherRecognizer, 'dropRequireFailure', this)) {
      return this;
    }

    otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);
    var index = inArray(this.requireFail, otherRecognizer);

    if (index > -1) {
      this.requireFail.splice(index, 1);
    }

    return this;
  };
  /**
   * @private
   * has require failures boolean
   * @returns {boolean}
   */


  _proto.hasRequireFailures = function hasRequireFailures() {
    return this.requireFail.length > 0;
  };
  /**
   * @private
   * if the recognizer can recognize simultaneous with an other recognizer
   * @param {Recognizer} otherRecognizer
   * @returns {Boolean}
   */


  _proto.canRecognizeWith = function canRecognizeWith(otherRecognizer) {
    return !!this.simultaneous[otherRecognizer.id];
  };
  /**
   * @private
   * You should use `tryEmit` instead of `emit` directly to check
   * that all the needed recognizers has failed before emitting.
   * @param {Object} input
   */


  _proto.emit = function emit(input) {
    var self = this;
    var state = this.state;

    function emit(event) {
      self.manager.emit(event, input);
    } // 'panstart' and 'panmove'


    if (state < STATE_ENDED) {
      emit(self.options.event + stateStr(state));
    }

    emit(self.options.event); // simple 'eventName' events

    if (input.additionalEvent) {
      // additional event(panleft, panright, pinchin, pinchout...)
      emit(input.additionalEvent);
    } // panend and pancancel


    if (state >= STATE_ENDED) {
      emit(self.options.event + stateStr(state));
    }
  };
  /**
   * @private
   * Check that all the require failure recognizers has failed,
   * if true, it emits a gesture event,
   * otherwise, setup the state to FAILED.
   * @param {Object} input
   */


  _proto.tryEmit = function tryEmit(input) {
    if (this.canEmit()) {
      return this.emit(input);
    } // it's failing anyway


    this.state = STATE_FAILED;
  };
  /**
   * @private
   * can we emit?
   * @returns {boolean}
   */


  _proto.canEmit = function canEmit() {
    var i = 0;

    while (i < this.requireFail.length) {
      if (!(this.requireFail[i].state & (STATE_FAILED | STATE_POSSIBLE))) {
        return false;
      }

      i++;
    }

    return true;
  };
  /**
   * @private
   * update the recognizer
   * @param {Object} inputData
   */


  _proto.recognize = function recognize(inputData) {
    // make a new copy of the inputData
    // so we can change the inputData without messing up the other recognizers
    var inputDataClone = assign$1({}, inputData); // is is enabled and allow recognizing?

    if (!boolOrFn(this.options.enable, [this, inputDataClone])) {
      this.reset();
      this.state = STATE_FAILED;
      return;
    } // reset when we've reached the end


    if (this.state & (STATE_RECOGNIZED | STATE_CANCELLED | STATE_FAILED)) {
      this.state = STATE_POSSIBLE;
    }

    this.state = this.process(inputDataClone); // the recognizer has recognized a gesture
    // so trigger an event

    if (this.state & (STATE_BEGAN | STATE_CHANGED | STATE_ENDED | STATE_CANCELLED)) {
      this.tryEmit(inputDataClone);
    }
  };
  /**
   * @private
   * return the state of the recognizer
   * the actual recognizing happens in this method
   * @virtual
   * @param {Object} inputData
   * @returns {constant} STATE
   */

  /* jshint ignore:start */


  _proto.process = function process(inputData) {};
  /* jshint ignore:end */

  /**
   * @private
   * return the preferred touch-action
   * @virtual
   * @returns {Array}
   */


  _proto.getTouchAction = function getTouchAction() {};
  /**
   * @private
   * called when the gesture isn't allowed to recognize
   * like when another is being recognized or it is disabled
   * @virtual
   */


  _proto.reset = function reset() {};

  return Recognizer;
}();

/**
 * @private
 * A tap is recognized when the pointer is doing a small tap/click. Multiple taps are recognized if they occur
 * between the given interval and position. The delay option can be used to recognize multi-taps without firing
 * a single tap.
 *
 * The eventData from the emitted event contains the property `tapCount`, which contains the amount of
 * multi-taps being recognized.
 * @constructor
 * @extends Recognizer
 */

var TapRecognizer =
/*#__PURE__*/
function (_Recognizer) {
  _inheritsLoose(TapRecognizer, _Recognizer);

  function TapRecognizer(options) {
    var _this;

    if (options === void 0) {
      options = {};
    }

    _this = _Recognizer.call(this, _extends({
      event: 'tap',
      pointers: 1,
      taps: 1,
      interval: 300,
      // max time between the multi-tap taps
      time: 250,
      // max time of the pointer to be down (like finger on the screen)
      threshold: 9,
      // a minimal movement is ok, but keep it low
      posThreshold: 10
    }, options)) || this; // previous time and center,
    // used for tap counting

    _this.pTime = false;
    _this.pCenter = false;
    _this._timer = null;
    _this._input = null;
    _this.count = 0;
    return _this;
  }

  var _proto = TapRecognizer.prototype;

  _proto.getTouchAction = function getTouchAction() {
    return [TOUCH_ACTION_MANIPULATION];
  };

  _proto.process = function process(input) {
    var _this2 = this;

    var options = this.options;
    var validPointers = input.pointers.length === options.pointers;
    var validMovement = input.distance < options.threshold;
    var validTouchTime = input.deltaTime < options.time;
    this.reset();

    if (input.eventType & INPUT_START && this.count === 0) {
      return this.failTimeout();
    } // we only allow little movement
    // and we've reached an end event, so a tap is possible


    if (validMovement && validTouchTime && validPointers) {
      if (input.eventType !== INPUT_END) {
        return this.failTimeout();
      }

      var validInterval = this.pTime ? input.timeStamp - this.pTime < options.interval : true;
      var validMultiTap = !this.pCenter || getDistance(this.pCenter, input.center) < options.posThreshold;
      this.pTime = input.timeStamp;
      this.pCenter = input.center;

      if (!validMultiTap || !validInterval) {
        this.count = 1;
      } else {
        this.count += 1;
      }

      this._input = input; // if tap count matches we have recognized it,
      // else it has began recognizing...

      var tapCount = this.count % options.taps;

      if (tapCount === 0) {
        // no failing requirements, immediately trigger the tap event
        // or wait as long as the multitap interval to trigger
        if (!this.hasRequireFailures()) {
          return STATE_RECOGNIZED;
        } else {
          this._timer = setTimeout(function () {
            _this2.state = STATE_RECOGNIZED;

            _this2.tryEmit();
          }, options.interval);
          return STATE_BEGAN;
        }
      }
    }

    return STATE_FAILED;
  };

  _proto.failTimeout = function failTimeout() {
    var _this3 = this;

    this._timer = setTimeout(function () {
      _this3.state = STATE_FAILED;
    }, this.options.interval);
    return STATE_FAILED;
  };

  _proto.reset = function reset() {
    clearTimeout(this._timer);
  };

  _proto.emit = function emit() {
    if (this.state === STATE_RECOGNIZED) {
      this._input.tapCount = this.count;
      this.manager.emit(this.options.event, this._input);
    }
  };

  return TapRecognizer;
}(Recognizer);

/**
 * @private
 * This recognizer is just used as a base for the simple attribute recognizers.
 * @constructor
 * @extends Recognizer
 */

var AttrRecognizer =
/*#__PURE__*/
function (_Recognizer) {
  _inheritsLoose(AttrRecognizer, _Recognizer);

  function AttrRecognizer(options) {
    if (options === void 0) {
      options = {};
    }

    return _Recognizer.call(this, _extends({
      pointers: 1
    }, options)) || this;
  }
  /**
   * @private
   * Used to check if it the recognizer receives valid input, like input.distance > 10.
   * @memberof AttrRecognizer
   * @param {Object} input
   * @returns {Boolean} recognized
   */


  var _proto = AttrRecognizer.prototype;

  _proto.attrTest = function attrTest(input) {
    var optionPointers = this.options.pointers;
    return optionPointers === 0 || input.pointers.length === optionPointers;
  };
  /**
   * @private
   * Process the input and return the state for the recognizer
   * @memberof AttrRecognizer
   * @param {Object} input
   * @returns {*} State
   */


  _proto.process = function process(input) {
    var state = this.state;
    var eventType = input.eventType;
    var isRecognized = state & (STATE_BEGAN | STATE_CHANGED);
    var isValid = this.attrTest(input); // on cancel input and we've recognized before, return STATE_CANCELLED

    if (isRecognized && (eventType & INPUT_CANCEL || !isValid)) {
      return state | STATE_CANCELLED;
    } else if (isRecognized || isValid) {
      if (eventType & INPUT_END) {
        return state | STATE_ENDED;
      } else if (!(state & STATE_BEGAN)) {
        return STATE_BEGAN;
      }

      return state | STATE_CHANGED;
    }

    return STATE_FAILED;
  };

  return AttrRecognizer;
}(Recognizer);

/**
 * @private
 * direction cons to string
 * @param {constant} direction
 * @returns {String}
 */

function directionStr(direction) {
  if (direction === DIRECTION_DOWN) {
    return 'down';
  } else if (direction === DIRECTION_UP) {
    return 'up';
  } else if (direction === DIRECTION_LEFT) {
    return 'left';
  } else if (direction === DIRECTION_RIGHT) {
    return 'right';
  }

  return '';
}

/**
 * @private
 * Pan
 * Recognized when the pointer is down and moved in the allowed direction.
 * @constructor
 * @extends AttrRecognizer
 */

var PanRecognizer =
/*#__PURE__*/
function (_AttrRecognizer) {
  _inheritsLoose(PanRecognizer, _AttrRecognizer);

  function PanRecognizer(options) {
    var _this;

    if (options === void 0) {
      options = {};
    }

    _this = _AttrRecognizer.call(this, _extends({
      event: 'pan',
      threshold: 10,
      pointers: 1,
      direction: DIRECTION_ALL
    }, options)) || this;
    _this.pX = null;
    _this.pY = null;
    return _this;
  }

  var _proto = PanRecognizer.prototype;

  _proto.getTouchAction = function getTouchAction() {
    var direction = this.options.direction;
    var actions = [];

    if (direction & DIRECTION_HORIZONTAL) {
      actions.push(TOUCH_ACTION_PAN_Y);
    }

    if (direction & DIRECTION_VERTICAL) {
      actions.push(TOUCH_ACTION_PAN_X);
    }

    return actions;
  };

  _proto.directionTest = function directionTest(input) {
    var options = this.options;
    var hasMoved = true;
    var distance = input.distance;
    var direction = input.direction;
    var x = input.deltaX;
    var y = input.deltaY; // lock to axis?

    if (!(direction & options.direction)) {
      if (options.direction & DIRECTION_HORIZONTAL) {
        direction = x === 0 ? DIRECTION_NONE : x < 0 ? DIRECTION_LEFT : DIRECTION_RIGHT;
        hasMoved = x !== this.pX;
        distance = Math.abs(input.deltaX);
      } else {
        direction = y === 0 ? DIRECTION_NONE : y < 0 ? DIRECTION_UP : DIRECTION_DOWN;
        hasMoved = y !== this.pY;
        distance = Math.abs(input.deltaY);
      }
    }

    input.direction = direction;
    return hasMoved && distance > options.threshold && direction & options.direction;
  };

  _proto.attrTest = function attrTest(input) {
    return AttrRecognizer.prototype.attrTest.call(this, input) && ( // replace with a super call
    this.state & STATE_BEGAN || !(this.state & STATE_BEGAN) && this.directionTest(input));
  };

  _proto.emit = function emit(input) {
    this.pX = input.deltaX;
    this.pY = input.deltaY;
    var direction = directionStr(input.direction);

    if (direction) {
      input.additionalEvent = this.options.event + direction;
    }

    _AttrRecognizer.prototype.emit.call(this, input);
  };

  return PanRecognizer;
}(AttrRecognizer);

/**
 * @private
 * Swipe
 * Recognized when the pointer is moving fast (velocity), with enough distance in the allowed direction.
 * @constructor
 * @extends AttrRecognizer
 */

var SwipeRecognizer =
/*#__PURE__*/
function (_AttrRecognizer) {
  _inheritsLoose(SwipeRecognizer, _AttrRecognizer);

  function SwipeRecognizer(options) {
    if (options === void 0) {
      options = {};
    }

    return _AttrRecognizer.call(this, _extends({
      event: 'swipe',
      threshold: 10,
      velocity: 0.3,
      direction: DIRECTION_HORIZONTAL | DIRECTION_VERTICAL,
      pointers: 1
    }, options)) || this;
  }

  var _proto = SwipeRecognizer.prototype;

  _proto.getTouchAction = function getTouchAction() {
    return PanRecognizer.prototype.getTouchAction.call(this);
  };

  _proto.attrTest = function attrTest(input) {
    var direction = this.options.direction;
    var velocity;

    if (direction & (DIRECTION_HORIZONTAL | DIRECTION_VERTICAL)) {
      velocity = input.overallVelocity;
    } else if (direction & DIRECTION_HORIZONTAL) {
      velocity = input.overallVelocityX;
    } else if (direction & DIRECTION_VERTICAL) {
      velocity = input.overallVelocityY;
    }

    return _AttrRecognizer.prototype.attrTest.call(this, input) && direction & input.offsetDirection && input.distance > this.options.threshold && input.maxPointers === this.options.pointers && abs(velocity) > this.options.velocity && input.eventType & INPUT_END;
  };

  _proto.emit = function emit(input) {
    var direction = directionStr(input.offsetDirection);

    if (direction) {
      this.manager.emit(this.options.event + direction, input);
    }

    this.manager.emit(this.options.event, input);
  };

  return SwipeRecognizer;
}(AttrRecognizer);

/**
 * @private
 * Pinch
 * Recognized when two or more pointers are moving toward (zoom-in) or away from each other (zoom-out).
 * @constructor
 * @extends AttrRecognizer
 */

var PinchRecognizer =
/*#__PURE__*/
function (_AttrRecognizer) {
  _inheritsLoose(PinchRecognizer, _AttrRecognizer);

  function PinchRecognizer(options) {
    if (options === void 0) {
      options = {};
    }

    return _AttrRecognizer.call(this, _extends({
      event: 'pinch',
      threshold: 0,
      pointers: 2
    }, options)) || this;
  }

  var _proto = PinchRecognizer.prototype;

  _proto.getTouchAction = function getTouchAction() {
    return [TOUCH_ACTION_NONE];
  };

  _proto.attrTest = function attrTest(input) {
    return _AttrRecognizer.prototype.attrTest.call(this, input) && (Math.abs(input.scale - 1) > this.options.threshold || this.state & STATE_BEGAN);
  };

  _proto.emit = function emit(input) {
    if (input.scale !== 1) {
      var inOut = input.scale < 1 ? 'in' : 'out';
      input.additionalEvent = this.options.event + inOut;
    }

    _AttrRecognizer.prototype.emit.call(this, input);
  };

  return PinchRecognizer;
}(AttrRecognizer);

/**
 * @private
 * Rotate
 * Recognized when two or more pointer are moving in a circular motion.
 * @constructor
 * @extends AttrRecognizer
 */

var RotateRecognizer =
/*#__PURE__*/
function (_AttrRecognizer) {
  _inheritsLoose(RotateRecognizer, _AttrRecognizer);

  function RotateRecognizer(options) {
    if (options === void 0) {
      options = {};
    }

    return _AttrRecognizer.call(this, _extends({
      event: 'rotate',
      threshold: 0,
      pointers: 2
    }, options)) || this;
  }

  var _proto = RotateRecognizer.prototype;

  _proto.getTouchAction = function getTouchAction() {
    return [TOUCH_ACTION_NONE];
  };

  _proto.attrTest = function attrTest(input) {
    return _AttrRecognizer.prototype.attrTest.call(this, input) && (Math.abs(input.rotation) > this.options.threshold || this.state & STATE_BEGAN);
  };

  return RotateRecognizer;
}(AttrRecognizer);

/**
 * @private
 * Press
 * Recognized when the pointer is down for x ms without any movement.
 * @constructor
 * @extends Recognizer
 */

var PressRecognizer =
/*#__PURE__*/
function (_Recognizer) {
  _inheritsLoose(PressRecognizer, _Recognizer);

  function PressRecognizer(options) {
    var _this;

    if (options === void 0) {
      options = {};
    }

    _this = _Recognizer.call(this, _extends({
      event: 'press',
      pointers: 1,
      time: 251,
      // minimal time of the pointer to be pressed
      threshold: 9
    }, options)) || this;
    _this._timer = null;
    _this._input = null;
    return _this;
  }

  var _proto = PressRecognizer.prototype;

  _proto.getTouchAction = function getTouchAction() {
    return [TOUCH_ACTION_AUTO];
  };

  _proto.process = function process(input) {
    var _this2 = this;

    var options = this.options;
    var validPointers = input.pointers.length === options.pointers;
    var validMovement = input.distance < options.threshold;
    var validTime = input.deltaTime > options.time;
    this._input = input; // we only allow little movement
    // and we've reached an end event, so a tap is possible

    if (!validMovement || !validPointers || input.eventType & (INPUT_END | INPUT_CANCEL) && !validTime) {
      this.reset();
    } else if (input.eventType & INPUT_START) {
      this.reset();
      this._timer = setTimeout(function () {
        _this2.state = STATE_RECOGNIZED;

        _this2.tryEmit();
      }, options.time);
    } else if (input.eventType & INPUT_END) {
      return STATE_RECOGNIZED;
    }

    return STATE_FAILED;
  };

  _proto.reset = function reset() {
    clearTimeout(this._timer);
  };

  _proto.emit = function emit(input) {
    if (this.state !== STATE_RECOGNIZED) {
      return;
    }

    if (input && input.eventType & INPUT_END) {
      this.manager.emit(this.options.event + "up", input);
    } else {
      this._input.timeStamp = now();
      this.manager.emit(this.options.event, this._input);
    }
  };

  return PressRecognizer;
}(Recognizer);

var defaults = {
  /**
   * @private
   * set if DOM events are being triggered.
   * But this is slower and unused by simple implementations, so disabled by default.
   * @type {Boolean}
   * @default false
   */
  domEvents: false,

  /**
   * @private
   * The value for the touchAction property/fallback.
   * When set to `compute` it will magically set the correct value based on the added recognizers.
   * @type {String}
   * @default compute
   */
  touchAction: TOUCH_ACTION_COMPUTE,

  /**
   * @private
   * @type {Boolean}
   * @default true
   */
  enable: true,

  /**
   * @private
   * EXPERIMENTAL FEATURE -- can be removed/changed
   * Change the parent input target element.
   * If Null, then it is being set the to main element.
   * @type {Null|EventTarget}
   * @default null
   */
  inputTarget: null,

  /**
   * @private
   * force an input class
   * @type {Null|Function}
   * @default null
   */
  inputClass: null,

  /**
   * @private
   * Some CSS properties can be used to improve the working of Hammer.
   * Add them to this method and they will be set when creating a new Manager.
   * @namespace
   */
  cssProps: {
    /**
     * @private
     * Disables text selection to improve the dragging gesture. Mainly for desktop browsers.
     * @type {String}
     * @default 'none'
     */
    userSelect: "none",

    /**
     * @private
     * Disable the Windows Phone grippers when pressing an element.
     * @type {String}
     * @default 'none'
     */
    touchSelect: "none",

    /**
     * @private
     * Disables the default callout shown when you touch and hold a touch target.
     * On iOS, when you touch and hold a touch target such as a link, Safari displays
     * a callout containing information about the link. This property allows you to disable that callout.
     * @type {String}
     * @default 'none'
     */
    touchCallout: "none",

    /**
     * @private
     * Specifies whether zooming is enabled. Used by IE10>
     * @type {String}
     * @default 'none'
     */
    contentZooming: "none",

    /**
     * @private
     * Specifies that an entire element should be draggable instead of its contents. Mainly for desktop browsers.
     * @type {String}
     * @default 'none'
     */
    userDrag: "none",

    /**
     * @private
     * Overrides the highlight color shown when the user taps a link or a JavaScript
     * clickable element in iOS. This property obeys the alpha value, if specified.
     * @type {String}
     * @default 'rgba(0,0,0,0)'
     */
    tapHighlightColor: "rgba(0,0,0,0)"
  }
};
/**
 * @private
 * Default recognizer setup when calling `Hammer()`
 * When creating a new Manager these will be skipped.
 * This is separated with other defaults because of tree-shaking.
 * @type {Array}
 */

var preset = [[RotateRecognizer, {
  enable: false
}], [PinchRecognizer, {
  enable: false
}, ['rotate']], [SwipeRecognizer, {
  direction: DIRECTION_HORIZONTAL
}], [PanRecognizer, {
  direction: DIRECTION_HORIZONTAL
}, ['swipe']], [TapRecognizer], [TapRecognizer, {
  event: 'doubletap',
  taps: 2
}, ['tap']], [PressRecognizer]];

var STOP = 1;
var FORCED_STOP = 2;
/**
 * @private
 * add/remove the css properties as defined in manager.options.cssProps
 * @param {Manager} manager
 * @param {Boolean} add
 */

function toggleCssProps(manager, add) {
  var element = manager.element;

  if (!element.style) {
    return;
  }

  var prop;
  each(manager.options.cssProps, function (value, name) {
    prop = prefixed(element.style, name);

    if (add) {
      manager.oldCssProps[prop] = element.style[prop];
      element.style[prop] = value;
    } else {
      element.style[prop] = manager.oldCssProps[prop] || "";
    }
  });

  if (!add) {
    manager.oldCssProps = {};
  }
}
/**
 * @private
 * trigger dom event
 * @param {String} event
 * @param {Object} data
 */


function triggerDomEvent(event, data) {
  var gestureEvent = document.createEvent("Event");
  gestureEvent.initEvent(event, true, true);
  gestureEvent.gesture = data;
  data.target.dispatchEvent(gestureEvent);
}
/**
* @private
 * Manager
 * @param {HTMLElement} element
 * @param {Object} [options]
 * @constructor
 */


var Manager =
/*#__PURE__*/
function () {
  function Manager(element, options) {
    var _this = this;

    this.options = assign$1({}, defaults, options || {});
    this.options.inputTarget = this.options.inputTarget || element;
    this.handlers = {};
    this.session = {};
    this.recognizers = [];
    this.oldCssProps = {};
    this.element = element;
    this.input = createInputInstance(this);
    this.touchAction = new TouchAction(this, this.options.touchAction);
    toggleCssProps(this, true);
    each(this.options.recognizers, function (item) {
      var recognizer = _this.add(new item[0](item[1]));

      item[2] && recognizer.recognizeWith(item[2]);
      item[3] && recognizer.requireFailure(item[3]);
    }, this);
  }
  /**
   * @private
   * set options
   * @param {Object} options
   * @returns {Manager}
   */


  var _proto = Manager.prototype;

  _proto.set = function set(options) {
    assign$1(this.options, options); // Options that need a little more setup

    if (options.touchAction) {
      this.touchAction.update();
    }

    if (options.inputTarget) {
      // Clean up existing event listeners and reinitialize
      this.input.destroy();
      this.input.target = options.inputTarget;
      this.input.init();
    }

    return this;
  };
  /**
   * @private
   * stop recognizing for this session.
   * This session will be discarded, when a new [input]start event is fired.
   * When forced, the recognizer cycle is stopped immediately.
   * @param {Boolean} [force]
   */


  _proto.stop = function stop(force) {
    this.session.stopped = force ? FORCED_STOP : STOP;
  };
  /**
   * @private
   * run the recognizers!
   * called by the inputHandler function on every movement of the pointers (touches)
   * it walks through all the recognizers and tries to detect the gesture that is being made
   * @param {Object} inputData
   */


  _proto.recognize = function recognize(inputData) {
    var session = this.session;

    if (session.stopped) {
      return;
    } // run the touch-action polyfill


    this.touchAction.preventDefaults(inputData);
    var recognizer;
    var recognizers = this.recognizers; // this holds the recognizer that is being recognized.
    // so the recognizer's state needs to be BEGAN, CHANGED, ENDED or RECOGNIZED
    // if no recognizer is detecting a thing, it is set to `null`

    var curRecognizer = session.curRecognizer; // reset when the last recognizer is recognized
    // or when we're in a new session

    if (!curRecognizer || curRecognizer && curRecognizer.state & STATE_RECOGNIZED) {
      session.curRecognizer = null;
      curRecognizer = null;
    }

    var i = 0;

    while (i < recognizers.length) {
      recognizer = recognizers[i]; // find out if we are allowed try to recognize the input for this one.
      // 1.   allow if the session is NOT forced stopped (see the .stop() method)
      // 2.   allow if we still haven't recognized a gesture in this session, or the this recognizer is the one
      //      that is being recognized.
      // 3.   allow if the recognizer is allowed to run simultaneous with the current recognized recognizer.
      //      this can be setup with the `recognizeWith()` method on the recognizer.

      if (session.stopped !== FORCED_STOP && ( // 1
      !curRecognizer || recognizer === curRecognizer || // 2
      recognizer.canRecognizeWith(curRecognizer))) {
        // 3
        recognizer.recognize(inputData);
      } else {
        recognizer.reset();
      } // if the recognizer has been recognizing the input as a valid gesture, we want to store this one as the
      // current active recognizer. but only if we don't already have an active recognizer


      if (!curRecognizer && recognizer.state & (STATE_BEGAN | STATE_CHANGED | STATE_ENDED)) {
        session.curRecognizer = recognizer;
        curRecognizer = recognizer;
      }

      i++;
    }
  };
  /**
   * @private
   * get a recognizer by its event name.
   * @param {Recognizer|String} recognizer
   * @returns {Recognizer|Null}
   */


  _proto.get = function get(recognizer) {
    if (recognizer instanceof Recognizer) {
      return recognizer;
    }

    var recognizers = this.recognizers;

    for (var i = 0; i < recognizers.length; i++) {
      if (recognizers[i].options.event === recognizer) {
        return recognizers[i];
      }
    }

    return null;
  };
  /**
   * @private add a recognizer to the manager
   * existing recognizers with the same event name will be removed
   * @param {Recognizer} recognizer
   * @returns {Recognizer|Manager}
   */


  _proto.add = function add(recognizer) {
    if (invokeArrayArg(recognizer, "add", this)) {
      return this;
    } // remove existing


    var existing = this.get(recognizer.options.event);

    if (existing) {
      this.remove(existing);
    }

    this.recognizers.push(recognizer);
    recognizer.manager = this;
    this.touchAction.update();
    return recognizer;
  };
  /**
   * @private
   * remove a recognizer by name or instance
   * @param {Recognizer|String} recognizer
   * @returns {Manager}
   */


  _proto.remove = function remove(recognizer) {
    if (invokeArrayArg(recognizer, "remove", this)) {
      return this;
    }

    var targetRecognizer = this.get(recognizer); // let's make sure this recognizer exists

    if (recognizer) {
      var recognizers = this.recognizers;
      var index = inArray(recognizers, targetRecognizer);

      if (index !== -1) {
        recognizers.splice(index, 1);
        this.touchAction.update();
      }
    }

    return this;
  };
  /**
   * @private
   * bind event
   * @param {String} events
   * @param {Function} handler
   * @returns {EventEmitter} this
   */


  _proto.on = function on(events, handler) {
    if (events === undefined || handler === undefined) {
      return this;
    }

    var handlers = this.handlers;
    each(splitStr(events), function (event) {
      handlers[event] = handlers[event] || [];
      handlers[event].push(handler);
    });
    return this;
  };
  /**
   * @private unbind event, leave emit blank to remove all handlers
   * @param {String} events
   * @param {Function} [handler]
   * @returns {EventEmitter} this
   */


  _proto.off = function off(events, handler) {
    if (events === undefined) {
      return this;
    }

    var handlers = this.handlers;
    each(splitStr(events), function (event) {
      if (!handler) {
        delete handlers[event];
      } else {
        handlers[event] && handlers[event].splice(inArray(handlers[event], handler), 1);
      }
    });
    return this;
  };
  /**
   * @private emit event to the listeners
   * @param {String} event
   * @param {Object} data
   */


  _proto.emit = function emit(event, data) {
    // we also want to trigger dom events
    if (this.options.domEvents) {
      triggerDomEvent(event, data);
    } // no handlers, so skip it all


    var handlers = this.handlers[event] && this.handlers[event].slice();

    if (!handlers || !handlers.length) {
      return;
    }

    data.type = event;

    data.preventDefault = function () {
      data.srcEvent.preventDefault();
    };

    var i = 0;

    while (i < handlers.length) {
      handlers[i](data);
      i++;
    }
  };
  /**
   * @private
   * destroy the manager and unbinds all events
   * it doesn't unbind dom events, that is the user own responsibility
   */


  _proto.destroy = function destroy() {
    this.element && toggleCssProps(this, false);
    this.handlers = {};
    this.session = {};
    this.input.destroy();
    this.element = null;
  };

  return Manager;
}();

var SINGLE_TOUCH_INPUT_MAP = {
  touchstart: INPUT_START,
  touchmove: INPUT_MOVE,
  touchend: INPUT_END,
  touchcancel: INPUT_CANCEL
};
var SINGLE_TOUCH_TARGET_EVENTS = 'touchstart';
var SINGLE_TOUCH_WINDOW_EVENTS = 'touchstart touchmove touchend touchcancel';
/**
 * @private
 * Touch events input
 * @constructor
 * @extends Input
 */

var SingleTouchInput =
/*#__PURE__*/
function (_Input) {
  _inheritsLoose(SingleTouchInput, _Input);

  function SingleTouchInput() {
    var _this;

    var proto = SingleTouchInput.prototype;
    proto.evTarget = SINGLE_TOUCH_TARGET_EVENTS;
    proto.evWin = SINGLE_TOUCH_WINDOW_EVENTS;
    _this = _Input.apply(this, arguments) || this;
    _this.started = false;
    return _this;
  }

  var _proto = SingleTouchInput.prototype;

  _proto.handler = function handler(ev) {
    var type = SINGLE_TOUCH_INPUT_MAP[ev.type]; // should we handle the touch events?

    if (type === INPUT_START) {
      this.started = true;
    }

    if (!this.started) {
      return;
    }

    var touches = normalizeSingleTouches.call(this, ev, type); // when done, reset the started state

    if (type & (INPUT_END | INPUT_CANCEL) && touches[0].length - touches[1].length === 0) {
      this.started = false;
    }

    this.callback(this.manager, type, {
      pointers: touches[0],
      changedPointers: touches[1],
      pointerType: INPUT_TYPE_TOUCH,
      srcEvent: ev
    });
  };

  return SingleTouchInput;
}(Input);

function normalizeSingleTouches(ev, type) {
  var all = toArray(ev.touches);
  var changed = toArray(ev.changedTouches);

  if (type & (INPUT_END | INPUT_CANCEL)) {
    all = uniqueArray(all.concat(changed), 'identifier', true);
  }

  return [all, changed];
}

/**
 * @private
 * wrap a method with a deprecation warning and stack trace
 * @param {Function} method
 * @param {String} name
 * @param {String} message
 * @returns {Function} A new function wrapping the supplied method.
 */
function deprecate(method, name, message) {
  var deprecationMessage = "DEPRECATED METHOD: " + name + "\n" + message + " AT \n";
  return function () {
    var e = new Error('get-stack-trace');
    var stack = e && e.stack ? e.stack.replace(/^[^\(]+?[\n$]/gm, '').replace(/^\s+at\s+/gm, '').replace(/^Object.<anonymous>\s*\(/gm, '{anonymous}()@') : 'Unknown Stack Trace';
    var log = window.console && (window.console.warn || window.console.log);

    if (log) {
      log.call(window.console, deprecationMessage, stack);
    }

    return method.apply(this, arguments);
  };
}

/**
 * @private
 * extend object.
 * means that properties in dest will be overwritten by the ones in src.
 * @param {Object} dest
 * @param {Object} src
 * @param {Boolean} [merge=false]
 * @returns {Object} dest
 */

var extend = deprecate(function (dest, src, merge) {
  var keys = Object.keys(src);
  var i = 0;

  while (i < keys.length) {
    if (!merge || merge && dest[keys[i]] === undefined) {
      dest[keys[i]] = src[keys[i]];
    }

    i++;
  }

  return dest;
}, 'extend', 'Use `assign`.');

/**
 * @private
 * merge the values from src in the dest.
 * means that properties that exist in dest will not be overwritten by src
 * @param {Object} dest
 * @param {Object} src
 * @returns {Object} dest
 */

var merge = deprecate(function (dest, src) {
  return extend(dest, src, true);
}, 'merge', 'Use `assign`.');

/**
 * @private
 * simple class inheritance
 * @param {Function} child
 * @param {Function} base
 * @param {Object} [properties]
 */

function inherit(child, base, properties) {
  var baseP = base.prototype;
  var childP;
  childP = child.prototype = Object.create(baseP);
  childP.constructor = child;
  childP._super = baseP;

  if (properties) {
    assign$1(childP, properties);
  }
}

/**
 * @private
 * simple function bind
 * @param {Function} fn
 * @param {Object} context
 * @returns {Function}
 */
function bindFn(fn, context) {
  return function boundFn() {
    return fn.apply(context, arguments);
  };
}

/**
 * @private
 * Simple way to create a manager with a default set of recognizers.
 * @param {HTMLElement} element
 * @param {Object} [options]
 * @constructor
 */

var Hammer =
/*#__PURE__*/
function () {
  var Hammer =
  /**
    * @private
    * @const {string}
    */
  function Hammer(element, options) {
    if (options === void 0) {
      options = {};
    }

    return new Manager(element, _extends({
      recognizers: preset.concat()
    }, options));
  };

  Hammer.VERSION = "2.0.17-rc";
  Hammer.DIRECTION_ALL = DIRECTION_ALL;
  Hammer.DIRECTION_DOWN = DIRECTION_DOWN;
  Hammer.DIRECTION_LEFT = DIRECTION_LEFT;
  Hammer.DIRECTION_RIGHT = DIRECTION_RIGHT;
  Hammer.DIRECTION_UP = DIRECTION_UP;
  Hammer.DIRECTION_HORIZONTAL = DIRECTION_HORIZONTAL;
  Hammer.DIRECTION_VERTICAL = DIRECTION_VERTICAL;
  Hammer.DIRECTION_NONE = DIRECTION_NONE;
  Hammer.DIRECTION_DOWN = DIRECTION_DOWN;
  Hammer.INPUT_START = INPUT_START;
  Hammer.INPUT_MOVE = INPUT_MOVE;
  Hammer.INPUT_END = INPUT_END;
  Hammer.INPUT_CANCEL = INPUT_CANCEL;
  Hammer.STATE_POSSIBLE = STATE_POSSIBLE;
  Hammer.STATE_BEGAN = STATE_BEGAN;
  Hammer.STATE_CHANGED = STATE_CHANGED;
  Hammer.STATE_ENDED = STATE_ENDED;
  Hammer.STATE_RECOGNIZED = STATE_RECOGNIZED;
  Hammer.STATE_CANCELLED = STATE_CANCELLED;
  Hammer.STATE_FAILED = STATE_FAILED;
  Hammer.Manager = Manager;
  Hammer.Input = Input;
  Hammer.TouchAction = TouchAction;
  Hammer.TouchInput = TouchInput;
  Hammer.MouseInput = MouseInput;
  Hammer.PointerEventInput = PointerEventInput;
  Hammer.TouchMouseInput = TouchMouseInput;
  Hammer.SingleTouchInput = SingleTouchInput;
  Hammer.Recognizer = Recognizer;
  Hammer.AttrRecognizer = AttrRecognizer;
  Hammer.Tap = TapRecognizer;
  Hammer.Pan = PanRecognizer;
  Hammer.Swipe = SwipeRecognizer;
  Hammer.Pinch = PinchRecognizer;
  Hammer.Rotate = RotateRecognizer;
  Hammer.Press = PressRecognizer;
  Hammer.on = addEventListeners;
  Hammer.off = removeEventListeners;
  Hammer.each = each;
  Hammer.merge = merge;
  Hammer.extend = extend;
  Hammer.bindFn = bindFn;
  Hammer.assign = assign$1;
  Hammer.inherit = inherit;
  Hammer.bindFn = bindFn;
  Hammer.prefixed = prefixed;
  Hammer.toArray = toArray;
  Hammer.inArray = inArray;
  Hammer.uniqueArray = uniqueArray;
  Hammer.splitStr = splitStr;
  Hammer.boolOrFn = boolOrFn;
  Hammer.hasParent = hasParent;
  Hammer.addEventListeners = addEventListeners;
  Hammer.removeEventListeners = removeEventListeners;
  Hammer.defaults = assign$1({}, defaults, {
    preset: preset
  });
  return Hammer;
}();

/**
 * vis-util
 * https://github.com/visjs/vis-util
 *
 * utilitie collection for visjs
 *
 * @version 5.0.2
 * @date    2021-02-06T21:33:57.447Z
 *
 * @copyright (c) 2011-2017 Almende B.V, http://almende.com
 * @copyright (c) 2017-2019 visjs contributors, https://github.com/visjs
 *
 * @license
 * vis.js is dual licensed under both
 *
 *   1. The Apache 2.0 License
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *   and
 *
 *   2. The MIT License
 *      http://opensource.org/licenses/MIT
 *
 * vis.js may be distributed under either license.
 */

/**
 * Use this symbol to delete properies in deepObjectAssign.
 */
const DELETE = Symbol("DELETE");
/**
 * Pure version of deepObjectAssign, it doesn't modify any of it's arguments.
 *
 * @param base - The base object that fullfils the whole interface T.
 * @param updates - Updates that may change or delete props.
 *
 * @returns A brand new instance with all the supplied objects deeply merged.
 */
function pureDeepObjectAssign(base, ...updates) {
    return deepObjectAssign({}, base, ...updates);
}
/**
 * Deep version of object assign with additional deleting by the DELETE symbol.
 *
 * @param values - Objects to be deeply merged.
 *
 * @returns The first object from values.
 */
function deepObjectAssign(...values) {
    const merged = deepObjectAssignNonentry(...values);
    stripDelete(merged);
    return merged;
}
/**
 * Deep version of object assign with additional deleting by the DELETE symbol.
 *
 * @remarks
 * This doesn't strip the DELETE symbols so they may end up in the final object.
 *
 * @param values - Objects to be deeply merged.
 *
 * @returns The first object from values.
 */
function deepObjectAssignNonentry(...values) {
    if (values.length < 2) {
        return values[0];
    }
    else if (values.length > 2) {
        return deepObjectAssignNonentry(deepObjectAssign(values[0], values[1]), ...values.slice(2));
    }
    const a = values[0];
    const b = values[1];
    for (const prop of Reflect.ownKeys(b)) {
        if (!Object.prototype.propertyIsEnumerable.call(b, prop)) ;
        else if (b[prop] === DELETE) {
            delete a[prop];
        }
        else if (a[prop] !== null &&
            b[prop] !== null &&
            typeof a[prop] === "object" &&
            typeof b[prop] === "object" &&
            !Array.isArray(a[prop]) &&
            !Array.isArray(b[prop])) {
            a[prop] = deepObjectAssignNonentry(a[prop], b[prop]);
        }
        else {
            a[prop] = clone(b[prop]);
        }
    }
    return a;
}
/**
 * Deep clone given object or array. In case of primitive simply return.
 *
 * @param a - Anything.
 *
 * @returns Deep cloned object/array or unchanged a.
 */
function clone(a) {
    if (Array.isArray(a)) {
        return a.map((value) => clone(value));
    }
    else if (typeof a === "object" && a !== null) {
        return deepObjectAssignNonentry({}, a);
    }
    else {
        return a;
    }
}
/**
 * Strip DELETE from given object.
 *
 * @param a - Object which may contain DELETE but won't after this is executed.
 */
function stripDelete(a) {
    for (const prop of Object.keys(a)) {
        if (a[prop] === DELETE) {
            delete a[prop];
        }
        else if (typeof a[prop] === "object" && a[prop] !== null) {
            stripDelete(a[prop]);
        }
    }
}

/**
 * Seedable, fast and reasonably good (not crypto but more than okay for our
 * needs) random number generator.
 *
 * @remarks
 * Adapted from {@link https://web.archive.org/web/20110429100736/http://baagoe.com:80/en/RandomMusings/javascript}.
 * Original algorithm created by Johannes Baagøe \<baagoe\@baagoe.com\> in 2010.
 */
/**
 * Create a seeded pseudo random generator based on Alea by Johannes Baagøe.
 *
 * @param seed - All supplied arguments will be used as a seed. In case nothing
 * is supplied the current time will be used to seed the generator.
 *
 * @returns A ready to use seeded generator.
 */
function Alea(...seed) {
    return AleaImplementation(seed.length ? seed : [Date.now()]);
}
/**
 * An implementation of [[Alea]] without user input validation.
 *
 * @param seed - The data that will be used to seed the generator.
 *
 * @returns A ready to use seeded generator.
 */
function AleaImplementation(seed) {
    let [s0, s1, s2] = mashSeed(seed);
    let c = 1;
    const random = () => {
        const t = 2091639 * s0 + c * 2.3283064365386963e-10; // 2^-32
        s0 = s1;
        s1 = s2;
        return (s2 = t - (c = t | 0));
    };
    random.uint32 = () => random() * 0x100000000; // 2^32
    random.fract53 = () => random() + ((random() * 0x200000) | 0) * 1.1102230246251565e-16; // 2^-53
    random.algorithm = "Alea";
    random.seed = seed;
    random.version = "0.9";
    return random;
}
/**
 * Turn arbitrary data into values [[AleaImplementation]] can use to generate
 * random numbers.
 *
 * @param seed - Arbitrary data that will be used as the seed.
 *
 * @returns Three numbers to use as initial values for [[AleaImplementation]].
 */
function mashSeed(...seed) {
    const mash = Mash();
    let s0 = mash(" ");
    let s1 = mash(" ");
    let s2 = mash(" ");
    for (let i = 0; i < seed.length; i++) {
        s0 -= mash(seed[i]);
        if (s0 < 0) {
            s0 += 1;
        }
        s1 -= mash(seed[i]);
        if (s1 < 0) {
            s1 += 1;
        }
        s2 -= mash(seed[i]);
        if (s2 < 0) {
            s2 += 1;
        }
    }
    return [s0, s1, s2];
}
/**
 * Create a new mash function.
 *
 * @returns A nonpure function that takes arbitrary [[Mashable]] data and turns
 * them into numbers.
 */
function Mash() {
    let n = 0xefc8249d;
    return function (data) {
        const string = data.toString();
        for (let i = 0; i < string.length; i++) {
            n += string.charCodeAt(i);
            let h = 0.02519603282416938 * n;
            n = h >>> 0;
            h -= n;
            h *= n;
            n = h >>> 0;
            h -= n;
            n += h * 0x100000000; // 2^32
        }
        return (n >>> 0) * 2.3283064365386963e-10; // 2^-32
    };
}

/**
 * Setup a mock hammer.js object, for unit testing.
 *
 * Inspiration: https://github.com/uber/deck.gl/pull/658
 *
 * @returns {{on: noop, off: noop, destroy: noop, emit: noop, get: get}}
 */
function hammerMock() {
  const noop = () => {};

  return {
    on: noop,
    off: noop,
    destroy: noop,
    emit: noop,

    get() {
      return {
        set: noop,
      };
    },
  };
}

const Hammer$1 =
  typeof window !== "undefined"
    ? window.Hammer || Hammer
    : function () {
        // hammer.js is only available in a browser, not in node.js. Replacing it with a mock object.
        return hammerMock();
      };

/**
 * Turn an element into an clickToUse element.
 * When not active, the element has a transparent overlay. When the overlay is
 * clicked, the mode is changed to active.
 * When active, the element is displayed with a blue border around it, and
 * the interactive contents of the element can be used. When clicked outside
 * the element, the elements mode is changed to inactive.
 *
 * @param {Element} container
 * @class Activator
 */
function Activator(container) {
  this._cleanupQueue = [];

  this.active = false;

  this._dom = {
    container,
    overlay: document.createElement("div"),
  };

  this._dom.overlay.classList.add("vis-overlay");

  this._dom.container.appendChild(this._dom.overlay);
  this._cleanupQueue.push(() => {
    this._dom.overlay.parentNode.removeChild(this._dom.overlay);
  });

  const hammer = Hammer$1(this._dom.overlay);
  hammer.on("tap", this._onTapOverlay.bind(this));
  this._cleanupQueue.push(() => {
    hammer.destroy();
    // FIXME: cleaning up hammer instances doesn't work (Timeline not removed
    // from memory)
  });

  // block all touch events (except tap)
  const events = [
    "tap",
    "doubletap",
    "press",
    "pinch",
    "pan",
    "panstart",
    "panmove",
    "panend",
  ];
  events.forEach((event) => {
    hammer.on(event, (event) => {
      event.srcEvent.stopPropagation();
    });
  });

  // attach a click event to the window, in order to deactivate when clicking outside the timeline
  if (document && document.body) {
    this._onClick = (event) => {
      if (!_hasParent(event.target, container)) {
        this.deactivate();
      }
    };
    document.body.addEventListener("click", this._onClick);
    this._cleanupQueue.push(() => {
      document.body.removeEventListener("click", this._onClick);
    });
  }

  // prepare escape key listener for deactivating when active
  this._escListener = (event) => {
    if (
      "key" in event
        ? event.key === "Escape"
        : event.keyCode === 27 /* the keyCode is for IE11 */
    ) {
      this.deactivate();
    }
  };
}

// turn into an event emitter
componentEmitter(Activator.prototype);

// The currently active activator
Activator.current = null;

/**
 * Destroy the activator. Cleans up all created DOM and event listeners
 */
Activator.prototype.destroy = function () {
  this.deactivate();

  for (const callback of this._cleanupQueue.splice(0).reverse()) {
    callback();
  }
};

/**
 * Activate the element
 * Overlay is hidden, element is decorated with a blue shadow border
 */
Activator.prototype.activate = function () {
  // we allow only one active activator at a time
  if (Activator.current) {
    Activator.current.deactivate();
  }
  Activator.current = this;

  this.active = true;
  this._dom.overlay.style.display = "none";
  this._dom.container.classList.add("vis-active");

  this.emit("change");
  this.emit("activate");

  // ugly hack: bind ESC after emitting the events, as the Network rebinds all
  // keyboard events on a 'change' event
  document.body.addEventListener("keydown", this._escListener);
};

/**
 * Deactivate the element
 * Overlay is displayed on top of the element
 */
Activator.prototype.deactivate = function () {
  this.active = false;
  this._dom.overlay.style.display = "block";
  this._dom.container.classList.remove("vis-active");
  document.body.removeEventListener("keydown", this._escListener);

  this.emit("change");
  this.emit("deactivate");
};

/**
 * Handle a tap event: activate the container
 *
 * @param {Event}  event   The event
 * @private
 */
Activator.prototype._onTapOverlay = function (event) {
  // activate the container
  this.activate();
  event.srcEvent.stopPropagation();
};

/**
 * Test whether the element has the requested parent element somewhere in
 * its chain of parent nodes.
 *
 * @param {HTMLElement} element
 * @param {HTMLElement} parent
 * @returns {boolean} Returns true when the parent is found somewhere in the
 *                    chain of parent nodes.
 * @private
 */
function _hasParent(element, parent) {
  while (element) {
    if (element === parent) {
      return true;
    }
    element = element.parentNode;
  }
  return false;
}

// utility functions
// parse ASP.Net Date pattern,
// for example '/Date(1198908717056)/' or '/Date(1198908717056-0700)/'
// code from http://momentjs.com/
const ASPDateRegex = /^\/?Date\((-?\d+)/i;
// Color REs
const fullHexRE = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i;
const shortHexRE = /^#?([a-f\d])([a-f\d])([a-f\d])$/i;
const rgbRE = /^rgb\( *(1?\d{1,2}|2[0-4]\d|25[0-5]) *, *(1?\d{1,2}|2[0-4]\d|25[0-5]) *, *(1?\d{1,2}|2[0-4]\d|25[0-5]) *\)$/i;
const rgbaRE = /^rgba\( *(1?\d{1,2}|2[0-4]\d|25[0-5]) *, *(1?\d{1,2}|2[0-4]\d|25[0-5]) *, *(1?\d{1,2}|2[0-4]\d|25[0-5]) *, *([01]|0?\.\d+) *\)$/i;
/**
 * Test whether given object is a number.
 *
 * @param value - Input value of unknown type.
 *
 * @returns True if number, false otherwise.
 */
function isNumber(value) {
    return value instanceof Number || typeof value === "number";
}
/**
 * Remove everything in the DOM object.
 *
 * @param DOMobject - Node whose child nodes will be recursively deleted.
 */
function recursiveDOMDelete(DOMobject) {
    if (DOMobject) {
        while (DOMobject.hasChildNodes() === true) {
            const child = DOMobject.firstChild;
            if (child) {
                recursiveDOMDelete(child);
                DOMobject.removeChild(child);
            }
        }
    }
}
/**
 * Test whether given object is a string.
 *
 * @param value - Input value of unknown type.
 *
 * @returns True if string, false otherwise.
 */
function isString(value) {
    return value instanceof String || typeof value === "string";
}
/**
 * Test whether given object is a object (not primitive or null).
 *
 * @param value - Input value of unknown type.
 *
 * @returns True if not null object, false otherwise.
 */
function isObject(value) {
    return typeof value === "object" && value !== null;
}
/**
 * Test whether given object is a Date, or a String containing a Date.
 *
 * @param value - Input value of unknown type.
 *
 * @returns True if Date instance or string date representation, false otherwise.
 */
function isDate(value) {
    if (value instanceof Date) {
        return true;
    }
    else if (isString(value)) {
        // test whether this string contains a date
        const match = ASPDateRegex.exec(value);
        if (match) {
            return true;
        }
        else if (!isNaN(Date.parse(value))) {
            return true;
        }
    }
    return false;
}
/**
 * Copy property from b to a if property present in a.
 * If property in b explicitly set to null, delete it if `allowDeletion` set.
 *
 * Internal helper routine, should not be exported. Not added to `exports` for that reason.
 *
 * @param a - Target object.
 * @param b - Source object.
 * @param prop - Name of property to copy from b to a.
 * @param allowDeletion - If true, delete property in a if explicitly set to null in b.
 */
function copyOrDelete(a, b, prop, allowDeletion) {
    let doDeletion = false;
    if (allowDeletion === true) {
        doDeletion = b[prop] === null && a[prop] !== undefined;
    }
    if (doDeletion) {
        delete a[prop];
    }
    else {
        a[prop] = b[prop]; // Remember, this is a reference copy!
    }
}
/**
 * Fill an object with a possibly partially defined other object.
 *
 * Only copies values for the properties already present in a.
 * That means an object is not created on a property if only the b object has it.
 *
 * @param a - The object that will have it's properties updated.
 * @param b - The object with property updates.
 * @param allowDeletion - If true, delete properties in a that are explicitly set to null in b.
 */
function fillIfDefined(a, b, allowDeletion = false) {
    // NOTE: iteration of properties of a
    // NOTE: prototype properties iterated over as well
    for (const prop in a) {
        if (b[prop] !== undefined) {
            if (b[prop] === null || typeof b[prop] !== "object") {
                // Note: typeof null === 'object'
                copyOrDelete(a, b, prop, allowDeletion);
            }
            else {
                const aProp = a[prop];
                const bProp = b[prop];
                if (isObject(aProp) && isObject(bProp)) {
                    fillIfDefined(aProp, bProp, allowDeletion);
                }
            }
        }
    }
}
/**
 * Copy the values of all of the enumerable own properties from one or more source objects to a
 * target object. Returns the target object.
 *
 * @param target - The target object to copy to.
 * @param source - The source object from which to copy properties.
 *
 * @returns The target object.
 */
const extend$1 = Object.assign;
/**
 * Extend object a with selected properties of object b or a series of objects.
 *
 * @remarks
 * Only properties with defined values are copied.
 *
 * @param props - Properties to be copied to a.
 * @param a - The target.
 * @param others - The sources.
 *
 * @returns Argument a.
 */
function selectiveExtend(props, a, ...others) {
    if (!Array.isArray(props)) {
        throw new Error("Array with property names expected as first argument");
    }
    for (const other of others) {
        for (let p = 0; p < props.length; p++) {
            const prop = props[p];
            if (other && Object.prototype.hasOwnProperty.call(other, prop)) {
                a[prop] = other[prop];
            }
        }
    }
    return a;
}
/**
 * Extend object a with selected properties of object b.
 * Only properties with defined values are copied.
 *
 * @remarks
 * Previous version of this routine implied that multiple source objects could
 * be used; however, the implementation was **wrong**. Since multiple (\>1)
 * sources weren't used anywhere in the `vis.js` code, this has been removed
 *
 * @param props - Names of first-level properties to copy over.
 * @param a - Target object.
 * @param b - Source object.
 * @param allowDeletion - If true, delete property in a if explicitly set to null in b.
 *
 * @returns Argument a.
 */
function selectiveDeepExtend(props, a, b, allowDeletion = false) {
    // TODO: add support for Arrays to deepExtend
    if (Array.isArray(b)) {
        throw new TypeError("Arrays are not supported by deepExtend");
    }
    for (let p = 0; p < props.length; p++) {
        const prop = props[p];
        if (Object.prototype.hasOwnProperty.call(b, prop)) {
            if (b[prop] && b[prop].constructor === Object) {
                if (a[prop] === undefined) {
                    a[prop] = {};
                }
                if (a[prop].constructor === Object) {
                    deepExtend(a[prop], b[prop], false, allowDeletion);
                }
                else {
                    copyOrDelete(a, b, prop, allowDeletion);
                }
            }
            else if (Array.isArray(b[prop])) {
                throw new TypeError("Arrays are not supported by deepExtend");
            }
            else {
                copyOrDelete(a, b, prop, allowDeletion);
            }
        }
    }
    return a;
}
/**
 * Extend object `a` with properties of object `b`, ignoring properties which
 * are explicitly specified to be excluded.
 *
 * @remarks
 * The properties of `b` are considered for copying. Properties which are
 * themselves objects are are also extended. Only properties with defined
 * values are copied.
 *
 * @param propsToExclude - Names of properties which should *not* be copied.
 * @param a - Object to extend.
 * @param b - Object to take properties from for extension.
 * @param allowDeletion - If true, delete properties in a that are explicitly
 * set to null in b.
 *
 * @returns Argument a.
 */
function selectiveNotDeepExtend(propsToExclude, a, b, allowDeletion = false) {
    // TODO: add support for Arrays to deepExtend
    // NOTE: array properties have an else-below; apparently, there is a problem here.
    if (Array.isArray(b)) {
        throw new TypeError("Arrays are not supported by deepExtend");
    }
    for (const prop in b) {
        if (!Object.prototype.hasOwnProperty.call(b, prop)) {
            continue;
        } // Handle local properties only
        if (propsToExclude.includes(prop)) {
            continue;
        } // In exclusion list, skip
        if (b[prop] && b[prop].constructor === Object) {
            if (a[prop] === undefined) {
                a[prop] = {};
            }
            if (a[prop].constructor === Object) {
                deepExtend(a[prop], b[prop]); // NOTE: allowDeletion not propagated!
            }
            else {
                copyOrDelete(a, b, prop, allowDeletion);
            }
        }
        else if (Array.isArray(b[prop])) {
            a[prop] = [];
            for (let i = 0; i < b[prop].length; i++) {
                a[prop].push(b[prop][i]);
            }
        }
        else {
            copyOrDelete(a, b, prop, allowDeletion);
        }
    }
    return a;
}
/**
 * Deep extend an object a with the properties of object b.
 *
 * @param a - Target object.
 * @param b - Source object.
 * @param protoExtend - If true, the prototype values will also be extended.
 * (That is the options objects that inherit from others will also get the
 * inherited options).
 * @param allowDeletion - If true, the values of fields that are null will be deleted.
 *
 * @returns Argument a.
 */
function deepExtend(a, b, protoExtend = false, allowDeletion = false) {
    for (const prop in b) {
        if (Object.prototype.hasOwnProperty.call(b, prop) || protoExtend === true) {
            if (typeof b[prop] === "object" &&
                b[prop] !== null &&
                Object.getPrototypeOf(b[prop]) === Object.prototype) {
                if (a[prop] === undefined) {
                    a[prop] = deepExtend({}, b[prop], protoExtend); // NOTE: allowDeletion not propagated!
                }
                else if (typeof a[prop] === "object" &&
                    a[prop] !== null &&
                    Object.getPrototypeOf(a[prop]) === Object.prototype) {
                    deepExtend(a[prop], b[prop], protoExtend); // NOTE: allowDeletion not propagated!
                }
                else {
                    copyOrDelete(a, b, prop, allowDeletion);
                }
            }
            else if (Array.isArray(b[prop])) {
                a[prop] = b[prop].slice();
            }
            else {
                copyOrDelete(a, b, prop, allowDeletion);
            }
        }
    }
    return a;
}
/**
 * Test whether all elements in two arrays are equal.
 *
 * @param a - First array.
 * @param b - Second array.
 *
 * @returns True if both arrays have the same length and same elements (1 = '1').
 */
function equalArray(a, b) {
    if (a.length !== b.length) {
        return false;
    }
    for (let i = 0, len = a.length; i < len; i++) {
        if (a[i] != b[i]) {
            return false;
        }
    }
    return true;
}
/**
 * Get the type of an object, for example exports.getType([]) returns 'Array'.
 *
 * @param object - Input value of unknown type.
 *
 * @returns Detected type.
 */
function getType(object) {
    const type = typeof object;
    if (type === "object") {
        if (object === null) {
            return "null";
        }
        if (object instanceof Boolean) {
            return "Boolean";
        }
        if (object instanceof Number) {
            return "Number";
        }
        if (object instanceof String) {
            return "String";
        }
        if (Array.isArray(object)) {
            return "Array";
        }
        if (object instanceof Date) {
            return "Date";
        }
        return "Object";
    }
    if (type === "number") {
        return "Number";
    }
    if (type === "boolean") {
        return "Boolean";
    }
    if (type === "string") {
        return "String";
    }
    if (type === undefined) {
        return "undefined";
    }
    return type;
}
/**
 * Used to extend an array and copy it. This is used to propagate paths recursively.
 *
 * @param arr - First part.
 * @param newValue - The value to be aadded into the array.
 *
 * @returns A new array with all items from arr and newValue (which is last).
 */
function copyAndExtendArray(arr, newValue) {
    return [...arr, newValue];
}
/**
 * Used to extend an array and copy it. This is used to propagate paths recursively.
 *
 * @param arr - The array to be copied.
 *
 * @returns Shallow copy of arr.
 */
function copyArray(arr) {
    return arr.slice();
}
/**
 * Retrieve the absolute left value of a DOM element.
 *
 * @param elem - A dom element, for example a div.
 *
 * @returns The absolute left position of this element in the browser page.
 */
function getAbsoluteLeft(elem) {
    return elem.getBoundingClientRect().left;
}
/**
 * Retrieve the absolute right value of a DOM element.
 *
 * @param elem - A dom element, for example a div.
 *
 * @returns The absolute right position of this element in the browser page.
 */
function getAbsoluteRight(elem) {
    return elem.getBoundingClientRect().right;
}
/**
 * Retrieve the absolute top value of a DOM element.
 *
 * @param elem - A dom element, for example a div.
 *
 * @returns The absolute top position of this element in the browser page.
 */
function getAbsoluteTop(elem) {
    return elem.getBoundingClientRect().top;
}
/**
 * Add a className to the given elements style.
 *
 * @param elem - The element to which the classes will be added.
 * @param classNames - Space separated list of classes.
 */
function addClassName(elem, classNames) {
    let classes = elem.className.split(" ");
    const newClasses = classNames.split(" ");
    classes = classes.concat(newClasses.filter(function (className) {
        return !classes.includes(className);
    }));
    elem.className = classes.join(" ");
}
/**
 * Remove a className from the given elements style.
 *
 * @param elem - The element from which the classes will be removed.
 * @param classNames - Space separated list of classes.
 */
function removeClassName(elem, classNames) {
    let classes = elem.className.split(" ");
    const oldClasses = classNames.split(" ");
    classes = classes.filter(function (className) {
        return !oldClasses.includes(className);
    });
    elem.className = classes.join(" ");
}
/**
 * For each method for both arrays and objects.
 * In case of an array, the built-in Array.forEach() is applied (**No, it's not!**).
 * In case of an Object, the method loops over all properties of the object.
 *
 * @param object - An Object or Array to be iterated over.
 * @param callback - Array.forEach-like callback.
 */
function forEach(object, callback) {
    if (Array.isArray(object)) {
        // array
        const len = object.length;
        for (let i = 0; i < len; i++) {
            callback(object[i], i, object);
        }
    }
    else {
        // object
        for (const key in object) {
            if (Object.prototype.hasOwnProperty.call(object, key)) {
                callback(object[key], key, object);
            }
        }
    }
}
/**
 * Convert an object into an array: all objects properties are put into the array. The resulting array is unordered.
 *
 * @param o - Object that contains the properties and methods.
 *
 * @returns An array of unordered values.
 */
const toArray$1 = Object.values;
/**
 * Update a property in an object.
 *
 * @param object - The object whose property will be updated.
 * @param key - Name of the property to be updated.
 * @param value - The new value to be assigned.
 *
 * @returns Whether the value was updated (true) or already strictly the same in the original object (false).
 */
function updateProperty(object, key, value) {
    if (object[key] !== value) {
        object[key] = value;
        return true;
    }
    else {
        return false;
    }
}
/**
 * Throttle the given function to be only executed once per animation frame.
 *
 * @param fn - The original function.
 *
 * @returns The throttled function.
 */
function throttle(fn) {
    let scheduled = false;
    return () => {
        if (!scheduled) {
            scheduled = true;
            requestAnimationFrame(() => {
                scheduled = false;
                fn();
            });
        }
    };
}
/**
 * Add and event listener. Works for all browsers.
 *
 * @param element - The element to bind the event listener to.
 * @param action - Same as Element.addEventListener(action, —, —).
 * @param listener - Same as Element.addEventListener(—, listener, —).
 * @param useCapture - Same as Element.addEventListener(—, —, useCapture).
 */
function addEventListener(element, action, listener, useCapture) {
    if (element.addEventListener) {
        if (useCapture === undefined) {
            useCapture = false;
        }
        if (action === "mousewheel" && navigator.userAgent.includes("Firefox")) {
            action = "DOMMouseScroll"; // For Firefox
        }
        element.addEventListener(action, listener, useCapture);
    }
    else {
        // @TODO: IE types? Does anyone care?
        element.attachEvent("on" + action, listener); // IE browsers
    }
}
/**
 * Remove an event listener from an element.
 *
 * @param element - The element to bind the event listener to.
 * @param action - Same as Element.removeEventListener(action, —, —).
 * @param listener - Same as Element.removeEventListener(—, listener, —).
 * @param useCapture - Same as Element.removeEventListener(—, —, useCapture).
 */
function removeEventListener(element, action, listener, useCapture) {
    if (element.removeEventListener) {
        // non-IE browsers
        if (useCapture === undefined) {
            useCapture = false;
        }
        if (action === "mousewheel" && navigator.userAgent.includes("Firefox")) {
            action = "DOMMouseScroll"; // For Firefox
        }
        element.removeEventListener(action, listener, useCapture);
    }
    else {
        // @TODO: IE types? Does anyone care?
        element.detachEvent("on" + action, listener); // IE browsers
    }
}
/**
 * Cancels the event's default action if it is cancelable, without stopping further propagation of the event.
 *
 * @param event - The event whose default action should be prevented.
 */
function preventDefault(event) {
    if (!event) {
        event = window.event;
    }
    if (!event) ;
    else if (event.preventDefault) {
        event.preventDefault(); // non-IE browsers
    }
    else {
        // @TODO: IE types? Does anyone care?
        event.returnValue = false; // IE browsers
    }
}
/**
 * Get HTML element which is the target of the event.
 *
 * @param event - The event.
 *
 * @returns The element or null if not obtainable.
 */
function getTarget(event = window.event) {
    // code from http://www.quirksmode.org/js/events_properties.html
    // @TODO: EventTarget can be almost anything, is it okay to return only Elements?
    let target = null;
    if (!event) ;
    else if (event.target) {
        target = event.target;
    }
    else if (event.srcElement) {
        target = event.srcElement;
    }
    if (!(target instanceof Element)) {
        return null;
    }
    if (target.nodeType != null && target.nodeType == 3) {
        // defeat Safari bug
        target = target.parentNode;
        if (!(target instanceof Element)) {
            return null;
        }
    }
    return target;
}
/**
 * Check if given element contains given parent somewhere in the DOM tree.
 *
 * @param element - The element to be tested.
 * @param parent - The ancestor (not necessarily parent) of the element.
 *
 * @returns True if parent is an ancestor of the element, false otherwise.
 */
function hasParent$1(element, parent) {
    let elem = element;
    while (elem) {
        if (elem === parent) {
            return true;
        }
        else if (elem.parentNode) {
            elem = elem.parentNode;
        }
        else {
            return false;
        }
    }
    return false;
}
const option = {
    /**
     * Convert a value into a boolean.
     *
     * @param value - Value to be converted intoboolean, a function will be executed as `(() => unknown)`.
     * @param defaultValue - If the value or the return value of the function == null then this will be returned.
     *
     * @returns Corresponding boolean value, if none then the default value, if none then null.
     */
    asBoolean(value, defaultValue) {
        if (typeof value == "function") {
            value = value();
        }
        if (value != null) {
            return value != false;
        }
        return defaultValue || null;
    },
    /**
     * Convert a value into a number.
     *
     * @param value - Value to be converted intonumber, a function will be executed as `(() => unknown)`.
     * @param defaultValue - If the value or the return value of the function == null then this will be returned.
     *
     * @returns Corresponding **boxed** number value, if none then the default value, if none then null.
     */
    asNumber(value, defaultValue) {
        if (typeof value == "function") {
            value = value();
        }
        if (value != null) {
            return Number(value) || defaultValue || null;
        }
        return defaultValue || null;
    },
    /**
     * Convert a value into a string.
     *
     * @param value - Value to be converted intostring, a function will be executed as `(() => unknown)`.
     * @param defaultValue - If the value or the return value of the function == null then this will be returned.
     *
     * @returns Corresponding **boxed** string value, if none then the default value, if none then null.
     */
    asString(value, defaultValue) {
        if (typeof value == "function") {
            value = value();
        }
        if (value != null) {
            return String(value);
        }
        return defaultValue || null;
    },
    /**
     * Convert a value into a size.
     *
     * @param value - Value to be converted intosize, a function will be executed as `(() => unknown)`.
     * @param defaultValue - If the value or the return value of the function == null then this will be returned.
     *
     * @returns Corresponding string value (number + 'px'), if none then the default value, if none then null.
     */
    asSize(value, defaultValue) {
        if (typeof value == "function") {
            value = value();
        }
        if (isString(value)) {
            return value;
        }
        else if (isNumber(value)) {
            return value + "px";
        }
        else {
            return defaultValue || null;
        }
    },
    /**
     * Convert a value into a DOM Element.
     *
     * @param value - Value to be converted into DOM Element, a function will be executed as `(() => unknown)`.
     * @param defaultValue - If the value or the return value of the function == null then this will be returned.
     *
     * @returns The DOM Element, if none then the default value, if none then null.
     */
    asElement(value, defaultValue) {
        if (typeof value == "function") {
            value = value();
        }
        return value || defaultValue || null;
    },
};
/**
 * Convert hex color string into RGB color object.
 *
 * @remarks
 * {@link http://stackoverflow.com/questions/5623838/rgb-to-hex-and-hex-to-rgb}
 *
 * @param hex - Hex color string (3 or 6 digits, with or without #).
 *
 * @returns RGB color object.
 */
function hexToRGB(hex) {
    let result;
    switch (hex.length) {
        case 3:
        case 4:
            result = shortHexRE.exec(hex);
            return result
                ? {
                    r: parseInt(result[1] + result[1], 16),
                    g: parseInt(result[2] + result[2], 16),
                    b: parseInt(result[3] + result[3], 16),
                }
                : null;
        case 6:
        case 7:
            result = fullHexRE.exec(hex);
            return result
                ? {
                    r: parseInt(result[1], 16),
                    g: parseInt(result[2], 16),
                    b: parseInt(result[3], 16),
                }
                : null;
        default:
            return null;
    }
}
/**
 * This function takes string color in hex or RGB format and adds the opacity, RGBA is passed through unchanged.
 *
 * @param color - The color string (hex, RGB, RGBA).
 * @param opacity - The new opacity.
 *
 * @returns RGBA string, for example 'rgba(255, 0, 127, 0.3)'.
 */
function overrideOpacity(color, opacity) {
    if (color.includes("rgba")) {
        return color;
    }
    else if (color.includes("rgb")) {
        const rgb = color
            .substr(color.indexOf("(") + 1)
            .replace(")", "")
            .split(",");
        return "rgba(" + rgb[0] + "," + rgb[1] + "," + rgb[2] + "," + opacity + ")";
    }
    else {
        const rgb = hexToRGB(color);
        if (rgb == null) {
            return color;
        }
        else {
            return "rgba(" + rgb.r + "," + rgb.g + "," + rgb.b + "," + opacity + ")";
        }
    }
}
/**
 * Convert RGB \<0, 255\> into hex color string.
 *
 * @param red - Red channel.
 * @param green - Green channel.
 * @param blue - Blue channel.
 *
 * @returns Hex color string (for example: '#0acdc0').
 */
function RGBToHex(red, green, blue) {
    return ("#" + ((1 << 24) + (red << 16) + (green << 8) + blue).toString(16).slice(1));
}
/**
 * Parse a color property into an object with border, background, and highlight colors.
 *
 * @param inputColor - Shorthand color string or input color object.
 * @param defaultColor - Full color object to fill in missing values in inputColor.
 *
 * @returns Color object.
 */
function parseColor(inputColor, defaultColor) {
    if (isString(inputColor)) {
        let colorStr = inputColor;
        if (isValidRGB(colorStr)) {
            const rgb = colorStr
                .substr(4)
                .substr(0, colorStr.length - 5)
                .split(",")
                .map(function (value) {
                return parseInt(value);
            });
            colorStr = RGBToHex(rgb[0], rgb[1], rgb[2]);
        }
        if (isValidHex(colorStr) === true) {
            const hsv = hexToHSV(colorStr);
            const lighterColorHSV = {
                h: hsv.h,
                s: hsv.s * 0.8,
                v: Math.min(1, hsv.v * 1.02),
            };
            const darkerColorHSV = {
                h: hsv.h,
                s: Math.min(1, hsv.s * 1.25),
                v: hsv.v * 0.8,
            };
            const darkerColorHex = HSVToHex(darkerColorHSV.h, darkerColorHSV.s, darkerColorHSV.v);
            const lighterColorHex = HSVToHex(lighterColorHSV.h, lighterColorHSV.s, lighterColorHSV.v);
            return {
                background: colorStr,
                border: darkerColorHex,
                highlight: {
                    background: lighterColorHex,
                    border: darkerColorHex,
                },
                hover: {
                    background: lighterColorHex,
                    border: darkerColorHex,
                },
            };
        }
        else {
            return {
                background: colorStr,
                border: colorStr,
                highlight: {
                    background: colorStr,
                    border: colorStr,
                },
                hover: {
                    background: colorStr,
                    border: colorStr,
                },
            };
        }
    }
    else {
        if (defaultColor) {
            const color = {
                background: inputColor.background || defaultColor.background,
                border: inputColor.border || defaultColor.border,
                highlight: isString(inputColor.highlight)
                    ? {
                        border: inputColor.highlight,
                        background: inputColor.highlight,
                    }
                    : {
                        background: (inputColor.highlight && inputColor.highlight.background) ||
                            defaultColor.highlight.background,
                        border: (inputColor.highlight && inputColor.highlight.border) ||
                            defaultColor.highlight.border,
                    },
                hover: isString(inputColor.hover)
                    ? {
                        border: inputColor.hover,
                        background: inputColor.hover,
                    }
                    : {
                        border: (inputColor.hover && inputColor.hover.border) ||
                            defaultColor.hover.border,
                        background: (inputColor.hover && inputColor.hover.background) ||
                            defaultColor.hover.background,
                    },
            };
            return color;
        }
        else {
            const color = {
                background: inputColor.background || undefined,
                border: inputColor.border || undefined,
                highlight: isString(inputColor.highlight)
                    ? {
                        border: inputColor.highlight,
                        background: inputColor.highlight,
                    }
                    : {
                        background: (inputColor.highlight && inputColor.highlight.background) ||
                            undefined,
                        border: (inputColor.highlight && inputColor.highlight.border) ||
                            undefined,
                    },
                hover: isString(inputColor.hover)
                    ? {
                        border: inputColor.hover,
                        background: inputColor.hover,
                    }
                    : {
                        border: (inputColor.hover && inputColor.hover.border) || undefined,
                        background: (inputColor.hover && inputColor.hover.background) || undefined,
                    },
            };
            return color;
        }
    }
}
/**
 * Convert RGB \<0, 255\> into HSV object.
 *
 * @remarks
 * {@link http://www.javascripter.net/faq/rgb2hsv.htm}
 *
 * @param red - Red channel.
 * @param green - Green channel.
 * @param blue - Blue channel.
 *
 * @returns HSV color object.
 */
function RGBToHSV(red, green, blue) {
    red = red / 255;
    green = green / 255;
    blue = blue / 255;
    const minRGB = Math.min(red, Math.min(green, blue));
    const maxRGB = Math.max(red, Math.max(green, blue));
    // Black-gray-white
    if (minRGB === maxRGB) {
        return { h: 0, s: 0, v: minRGB };
    }
    // Colors other than black-gray-white:
    const d = red === minRGB ? green - blue : blue === minRGB ? red - green : blue - red;
    const h = red === minRGB ? 3 : blue === minRGB ? 1 : 5;
    const hue = (60 * (h - d / (maxRGB - minRGB))) / 360;
    const saturation = (maxRGB - minRGB) / maxRGB;
    const value = maxRGB;
    return { h: hue, s: saturation, v: value };
}
const cssUtil = {
    // split a string with css styles into an object with key/values
    split(cssText) {
        const styles = {};
        cssText.split(";").forEach((style) => {
            if (style.trim() != "") {
                const parts = style.split(":");
                const key = parts[0].trim();
                const value = parts[1].trim();
                styles[key] = value;
            }
        });
        return styles;
    },
    // build a css text string from an object with key/values
    join(styles) {
        return Object.keys(styles)
            .map(function (key) {
            return key + ": " + styles[key];
        })
            .join("; ");
    },
};
/**
 * Append a string with css styles to an element.
 *
 * @param element - The element that will receive new styles.
 * @param cssText - The styles to be appended.
 */
function addCssText(element, cssText) {
    const currentStyles = cssUtil.split(element.style.cssText);
    const newStyles = cssUtil.split(cssText);
    const styles = {
        ...currentStyles,
        ...newStyles,
    };
    element.style.cssText = cssUtil.join(styles);
}
/**
 * Remove a string with css styles from an element.
 *
 * @param element - The element from which styles should be removed.
 * @param cssText - The styles to be removed.
 */
function removeCssText(element, cssText) {
    const styles = cssUtil.split(element.style.cssText);
    const removeStyles = cssUtil.split(cssText);
    for (const key in removeStyles) {
        if (Object.prototype.hasOwnProperty.call(removeStyles, key)) {
            delete styles[key];
        }
    }
    element.style.cssText = cssUtil.join(styles);
}
/**
 * Convert HSV \<0, 1\> into RGB color object.
 *
 * @remarks
 * {@link https://gist.github.com/mjijackson/5311256}
 *
 * @param h - Hue.
 * @param s - Saturation.
 * @param v - Value.
 *
 * @returns RGB color object.
 */
function HSVToRGB(h, s, v) {
    let r;
    let g;
    let b;
    const i = Math.floor(h * 6);
    const f = h * 6 - i;
    const p = v * (1 - s);
    const q = v * (1 - f * s);
    const t = v * (1 - (1 - f) * s);
    switch (i % 6) {
        case 0:
            (r = v), (g = t), (b = p);
            break;
        case 1:
            (r = q), (g = v), (b = p);
            break;
        case 2:
            (r = p), (g = v), (b = t);
            break;
        case 3:
            (r = p), (g = q), (b = v);
            break;
        case 4:
            (r = t), (g = p), (b = v);
            break;
        case 5:
            (r = v), (g = p), (b = q);
            break;
    }
    return {
        r: Math.floor(r * 255),
        g: Math.floor(g * 255),
        b: Math.floor(b * 255),
    };
}
/**
 * Convert HSV \<0, 1\> into hex color string.
 *
 * @param h - Hue.
 * @param s - Saturation.
 * @param v - Value.
 *
 * @returns Hex color string.
 */
function HSVToHex(h, s, v) {
    const rgb = HSVToRGB(h, s, v);
    return RGBToHex(rgb.r, rgb.g, rgb.b);
}
/**
 * Convert hex color string into HSV \<0, 1\>.
 *
 * @param hex - Hex color string.
 *
 * @returns HSV color object.
 */
function hexToHSV(hex) {
    const rgb = hexToRGB(hex);
    if (!rgb) {
        throw new TypeError(`'${hex}' is not a valid color.`);
    }
    return RGBToHSV(rgb.r, rgb.g, rgb.b);
}
/**
 * Validate hex color string.
 *
 * @param hex - Unknown string that may contain a color.
 *
 * @returns True if the string is valid, false otherwise.
 */
function isValidHex(hex) {
    const isOk = /(^#[0-9A-F]{6}$)|(^#[0-9A-F]{3}$)/i.test(hex);
    return isOk;
}
/**
 * Validate RGB color string.
 *
 * @param rgb - Unknown string that may contain a color.
 *
 * @returns True if the string is valid, false otherwise.
 */
function isValidRGB(rgb) {
    return rgbRE.test(rgb);
}
/**
 * Validate RGBA color string.
 *
 * @param rgba - Unknown string that may contain a color.
 *
 * @returns True if the string is valid, false otherwise.
 */
function isValidRGBA(rgba) {
    return rgbaRE.test(rgba);
}
/**
 * This recursively redirects the prototype of JSON objects to the referenceObject.
 * This is used for default options.
 *
 * @param fields - Names of properties to be bridged.
 * @param referenceObject - The original object.
 *
 * @returns A new object inheriting from the referenceObject.
 */
function selectiveBridgeObject(fields, referenceObject) {
    if (referenceObject !== null && typeof referenceObject === "object") {
        // !!! typeof null === 'object'
        const objectTo = Object.create(referenceObject);
        for (let i = 0; i < fields.length; i++) {
            if (Object.prototype.hasOwnProperty.call(referenceObject, fields[i])) {
                if (typeof referenceObject[fields[i]] == "object") {
                    objectTo[fields[i]] = bridgeObject(referenceObject[fields[i]]);
                }
            }
        }
        return objectTo;
    }
    else {
        return null;
    }
}
/**
 * This recursively redirects the prototype of JSON objects to the referenceObject.
 * This is used for default options.
 *
 * @param referenceObject - The original object.
 *
 * @returns The Element if the referenceObject is an Element, or a new object inheriting from the referenceObject.
 */
function bridgeObject(referenceObject) {
    if (referenceObject === null || typeof referenceObject !== "object") {
        return null;
    }
    if (referenceObject instanceof Element) {
        // Avoid bridging DOM objects
        return referenceObject;
    }
    const objectTo = Object.create(referenceObject);
    for (const i in referenceObject) {
        if (Object.prototype.hasOwnProperty.call(referenceObject, i)) {
            if (typeof referenceObject[i] == "object") {
                objectTo[i] = bridgeObject(referenceObject[i]);
            }
        }
    }
    return objectTo;
}
/**
 * This method provides a stable sort implementation, very fast for presorted data.
 *
 * @param a - The array to be sorted (in-place).
 * @param compare - An order comparator.
 *
 * @returns The argument a.
 */
function insertSort(a, compare) {
    for (let i = 0; i < a.length; i++) {
        const k = a[i];
        let j;
        for (j = i; j > 0 && compare(k, a[j - 1]) < 0; j--) {
            a[j] = a[j - 1];
        }
        a[j] = k;
    }
    return a;
}
/**
 * This is used to set the options of subobjects in the options object.
 *
 * A requirement of these subobjects is that they have an 'enabled' element
 * which is optional for the user but mandatory for the program.
 *
 * The added value here of the merge is that option 'enabled' is set as required.
 *
 * @param mergeTarget - Either this.options or the options used for the groups.
 * @param options - Options.
 * @param option - Option key in the options argument.
 * @param globalOptions - Global options, passed in to determine value of option 'enabled'.
 */
function mergeOptions(mergeTarget, options, option, globalOptions = {}) {
    // Local helpers
    const isPresent = function (obj) {
        return obj !== null && obj !== undefined;
    };
    const isObject = function (obj) {
        return obj !== null && typeof obj === "object";
    };
    // https://stackoverflow.com/a/34491287/1223531
    const isEmpty = function (obj) {
        for (const x in obj) {
            if (Object.prototype.hasOwnProperty.call(obj, x)) {
                return false;
            }
        }
        return true;
    };
    // Guards
    if (!isObject(mergeTarget)) {
        throw new Error("Parameter mergeTarget must be an object");
    }
    if (!isObject(options)) {
        throw new Error("Parameter options must be an object");
    }
    if (!isPresent(option)) {
        throw new Error("Parameter option must have a value");
    }
    if (!isObject(globalOptions)) {
        throw new Error("Parameter globalOptions must be an object");
    }
    //
    // Actual merge routine, separated from main logic
    // Only a single level of options is merged. Deeper levels are ref'd. This may actually be an issue.
    //
    const doMerge = function (target, options, option) {
        if (!isObject(target[option])) {
            target[option] = {};
        }
        const src = options[option];
        const dst = target[option];
        for (const prop in src) {
            if (Object.prototype.hasOwnProperty.call(src, prop)) {
                dst[prop] = src[prop];
            }
        }
    };
    // Local initialization
    const srcOption = options[option];
    const globalPassed = isObject(globalOptions) && !isEmpty(globalOptions);
    const globalOption = globalPassed ? globalOptions[option] : undefined;
    const globalEnabled = globalOption ? globalOption.enabled : undefined;
    /////////////////////////////////////////
    // Main routine
    /////////////////////////////////////////
    if (srcOption === undefined) {
        return; // Nothing to do
    }
    if (typeof srcOption === "boolean") {
        if (!isObject(mergeTarget[option])) {
            mergeTarget[option] = {};
        }
        mergeTarget[option].enabled = srcOption;
        return;
    }
    if (srcOption === null && !isObject(mergeTarget[option])) {
        // If possible, explicit copy from globals
        if (isPresent(globalOption)) {
            mergeTarget[option] = Object.create(globalOption);
        }
        else {
            return; // Nothing to do
        }
    }
    if (!isObject(srcOption)) {
        return;
    }
    //
    // Ensure that 'enabled' is properly set. It is required internally
    // Note that the value from options will always overwrite the existing value
    //
    let enabled = true; // default value
    if (srcOption.enabled !== undefined) {
        enabled = srcOption.enabled;
    }
    else {
        // Take from globals, if present
        if (globalEnabled !== undefined) {
            enabled = globalOption.enabled;
        }
    }
    doMerge(mergeTarget, options, option);
    mergeTarget[option].enabled = enabled;
}
/**
 * This function does a binary search for a visible item in a sorted list. If we find a visible item, the code that uses
 * this function will then iterate in both directions over this sorted list to find all visible items.
 *
 * @param orderedItems - Items ordered by start.
 * @param comparator - -1 is lower, 0 is equal, 1 is higher.
 * @param field - Property name on an item (That is item[field]).
 * @param field2 - Second property name on an item (That is item[field][field2]).
 *
 * @returns Index of the found item or -1 if nothing was found.
 */
function binarySearchCustom(orderedItems, comparator, field, field2) {
    const maxIterations = 10000;
    let iteration = 0;
    let low = 0;
    let high = orderedItems.length - 1;
    while (low <= high && iteration < maxIterations) {
        const middle = Math.floor((low + high) / 2);
        const item = orderedItems[middle];
        const value = field2 === undefined ? item[field] : item[field][field2];
        const searchResult = comparator(value);
        if (searchResult == 0) {
            // jihaa, found a visible item!
            return middle;
        }
        else if (searchResult == -1) {
            // it is too small --> increase low
            low = middle + 1;
        }
        else {
            // it is too big --> decrease high
            high = middle - 1;
        }
        iteration++;
    }
    return -1;
}
/**
 * This function does a binary search for a specific value in a sorted array.
 * If it does not exist but is in between of two values, we return either the
 * one before or the one after, depending on user input If it is found, we
 * return the index, else -1.
 *
 * @param orderedItems - Sorted array.
 * @param target - The searched value.
 * @param field - Name of the property in items to be searched.
 * @param sidePreference - If the target is between two values, should the index of the before or the after be returned?
 * @param comparator - An optional comparator, returning -1, 0, 1 for \<, ===, \>.
 *
 * @returns The index of found value or -1 if nothing was found.
 */
function binarySearchValue(orderedItems, target, field, sidePreference, comparator) {
    const maxIterations = 10000;
    let iteration = 0;
    let low = 0;
    let high = orderedItems.length - 1;
    let prevValue;
    let value;
    let nextValue;
    let middle;
    comparator =
        comparator != undefined
            ? comparator
            : function (a, b) {
                return a == b ? 0 : a < b ? -1 : 1;
            };
    while (low <= high && iteration < maxIterations) {
        // get a new guess
        middle = Math.floor(0.5 * (high + low));
        prevValue = orderedItems[Math.max(0, middle - 1)][field];
        value = orderedItems[middle][field];
        nextValue =
            orderedItems[Math.min(orderedItems.length - 1, middle + 1)][field];
        if (comparator(value, target) == 0) {
            // we found the target
            return middle;
        }
        else if (comparator(prevValue, target) < 0 &&
            comparator(value, target) > 0) {
            // target is in between of the previous and the current
            return sidePreference == "before" ? Math.max(0, middle - 1) : middle;
        }
        else if (comparator(value, target) < 0 &&
            comparator(nextValue, target) > 0) {
            // target is in between of the current and the next
            return sidePreference == "before"
                ? middle
                : Math.min(orderedItems.length - 1, middle + 1);
        }
        else {
            // didnt find the target, we need to change our boundaries.
            if (comparator(value, target) < 0) {
                // it is too small --> increase low
                low = middle + 1;
            }
            else {
                // it is too big --> decrease high
                high = middle - 1;
            }
        }
        iteration++;
    }
    // didnt find anything. Return -1.
    return -1;
}
/*
 * Easing Functions.
 * Only considering the t value for the range [0, 1] => [0, 1].
 *
 * Inspiration: from http://gizma.com/easing/
 * https://gist.github.com/gre/1650294
 */
const easingFunctions = {
    /**
     * Provides no easing and no acceleration.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    linear(t) {
        return t;
    },
    /**
     * Accelerate from zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInQuad(t) {
        return t * t;
    },
    /**
     * Decelerate to zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeOutQuad(t) {
        return t * (2 - t);
    },
    /**
     * Accelerate until halfway, then decelerate.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInOutQuad(t) {
        return t < 0.5 ? 2 * t * t : -1 + (4 - 2 * t) * t;
    },
    /**
     * Accelerate from zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInCubic(t) {
        return t * t * t;
    },
    /**
     * Decelerate to zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeOutCubic(t) {
        return --t * t * t + 1;
    },
    /**
     * Accelerate until halfway, then decelerate.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInOutCubic(t) {
        return t < 0.5 ? 4 * t * t * t : (t - 1) * (2 * t - 2) * (2 * t - 2) + 1;
    },
    /**
     * Accelerate from zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInQuart(t) {
        return t * t * t * t;
    },
    /**
     * Decelerate to zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeOutQuart(t) {
        return 1 - --t * t * t * t;
    },
    /**
     * Accelerate until halfway, then decelerate.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInOutQuart(t) {
        return t < 0.5 ? 8 * t * t * t * t : 1 - 8 * --t * t * t * t;
    },
    /**
     * Accelerate from zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInQuint(t) {
        return t * t * t * t * t;
    },
    /**
     * Decelerate to zero velocity.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeOutQuint(t) {
        return 1 + --t * t * t * t * t;
    },
    /**
     * Accelerate until halfway, then decelerate.
     *
     * @param t - Time.
     *
     * @returns Value at time t.
     */
    easeInOutQuint(t) {
        return t < 0.5 ? 16 * t * t * t * t * t : 1 + 16 * --t * t * t * t * t;
    },
};
/**
 * Experimentaly compute the width of the scrollbar for this browser.
 *
 * @returns The width in pixels.
 */
function getScrollBarWidth() {
    const inner = document.createElement("p");
    inner.style.width = "100%";
    inner.style.height = "200px";
    const outer = document.createElement("div");
    outer.style.position = "absolute";
    outer.style.top = "0px";
    outer.style.left = "0px";
    outer.style.visibility = "hidden";
    outer.style.width = "200px";
    outer.style.height = "150px";
    outer.style.overflow = "hidden";
    outer.appendChild(inner);
    document.body.appendChild(outer);
    const w1 = inner.offsetWidth;
    outer.style.overflow = "scroll";
    let w2 = inner.offsetWidth;
    if (w1 == w2) {
        w2 = outer.clientWidth;
    }
    document.body.removeChild(outer);
    return w1 - w2;
}
// @TODO: This doesn't work properly.
// It works only for single property objects,
// otherwise it combines all of the types in a union.
// export function topMost<K1 extends string, V1> (
//   pile: Record<K1, undefined | V1>[],
//   accessors: K1 | [K1]
// ): undefined | V1
// export function topMost<K1 extends string, K2 extends string, V1, V2> (
//   pile: Record<K1, undefined | V1 | Record<K2, undefined | V2>>[],
//   accessors: [K1, K2]
// ): undefined | V1 | V2
// export function topMost<K1 extends string, K2 extends string, K3 extends string, V1, V2, V3> (
//   pile: Record<K1, undefined | V1 | Record<K2, undefined | V2 | Record<K3, undefined | V3>>>[],
//   accessors: [K1, K2, K3]
// ): undefined | V1 | V2 | V3
/**
 * Get the top most property value from a pile of objects.
 *
 * @param pile - Array of objects, no required format.
 * @param accessors - Array of property names.
 * For example `object['foo']['bar']` → `['foo', 'bar']`.
 *
 * @returns Value of the property with given accessors path from the first pile item where it's not undefined.
 */
function topMost(pile, accessors) {
    let candidate;
    if (!Array.isArray(accessors)) {
        accessors = [accessors];
    }
    for (const member of pile) {
        if (member) {
            candidate = member[accessors[0]];
            for (let i = 1; i < accessors.length; i++) {
                if (candidate) {
                    candidate = candidate[accessors[i]];
                }
            }
            if (typeof candidate !== "undefined") {
                break;
            }
        }
    }
    return candidate;
}

const htmlColors = {
  black: "#000000",
  navy: "#000080",
  darkblue: "#00008B",
  mediumblue: "#0000CD",
  blue: "#0000FF",
  darkgreen: "#006400",
  green: "#008000",
  teal: "#008080",
  darkcyan: "#008B8B",
  deepskyblue: "#00BFFF",
  darkturquoise: "#00CED1",
  mediumspringgreen: "#00FA9A",
  lime: "#00FF00",
  springgreen: "#00FF7F",
  aqua: "#00FFFF",
  cyan: "#00FFFF",
  midnightblue: "#191970",
  dodgerblue: "#1E90FF",
  lightseagreen: "#20B2AA",
  forestgreen: "#228B22",
  seagreen: "#2E8B57",
  darkslategray: "#2F4F4F",
  limegreen: "#32CD32",
  mediumseagreen: "#3CB371",
  turquoise: "#40E0D0",
  royalblue: "#4169E1",
  steelblue: "#4682B4",
  darkslateblue: "#483D8B",
  mediumturquoise: "#48D1CC",
  indigo: "#4B0082",
  darkolivegreen: "#556B2F",
  cadetblue: "#5F9EA0",
  cornflowerblue: "#6495ED",
  mediumaquamarine: "#66CDAA",
  dimgray: "#696969",
  slateblue: "#6A5ACD",
  olivedrab: "#6B8E23",
  slategray: "#708090",
  lightslategray: "#778899",
  mediumslateblue: "#7B68EE",
  lawngreen: "#7CFC00",
  chartreuse: "#7FFF00",
  aquamarine: "#7FFFD4",
  maroon: "#800000",
  purple: "#800080",
  olive: "#808000",
  gray: "#808080",
  skyblue: "#87CEEB",
  lightskyblue: "#87CEFA",
  blueviolet: "#8A2BE2",
  darkred: "#8B0000",
  darkmagenta: "#8B008B",
  saddlebrown: "#8B4513",
  darkseagreen: "#8FBC8F",
  lightgreen: "#90EE90",
  mediumpurple: "#9370D8",
  darkviolet: "#9400D3",
  palegreen: "#98FB98",
  darkorchid: "#9932CC",
  yellowgreen: "#9ACD32",
  sienna: "#A0522D",
  brown: "#A52A2A",
  darkgray: "#A9A9A9",
  lightblue: "#ADD8E6",
  greenyellow: "#ADFF2F",
  paleturquoise: "#AFEEEE",
  lightsteelblue: "#B0C4DE",
  powderblue: "#B0E0E6",
  firebrick: "#B22222",
  darkgoldenrod: "#B8860B",
  mediumorchid: "#BA55D3",
  rosybrown: "#BC8F8F",
  darkkhaki: "#BDB76B",
  silver: "#C0C0C0",
  mediumvioletred: "#C71585",
  indianred: "#CD5C5C",
  peru: "#CD853F",
  chocolate: "#D2691E",
  tan: "#D2B48C",
  lightgrey: "#D3D3D3",
  palevioletred: "#D87093",
  thistle: "#D8BFD8",
  orchid: "#DA70D6",
  goldenrod: "#DAA520",
  crimson: "#DC143C",
  gainsboro: "#DCDCDC",
  plum: "#DDA0DD",
  burlywood: "#DEB887",
  lightcyan: "#E0FFFF",
  lavender: "#E6E6FA",
  darksalmon: "#E9967A",
  violet: "#EE82EE",
  palegoldenrod: "#EEE8AA",
  lightcoral: "#F08080",
  khaki: "#F0E68C",
  aliceblue: "#F0F8FF",
  honeydew: "#F0FFF0",
  azure: "#F0FFFF",
  sandybrown: "#F4A460",
  wheat: "#F5DEB3",
  beige: "#F5F5DC",
  whitesmoke: "#F5F5F5",
  mintcream: "#F5FFFA",
  ghostwhite: "#F8F8FF",
  salmon: "#FA8072",
  antiquewhite: "#FAEBD7",
  linen: "#FAF0E6",
  lightgoldenrodyellow: "#FAFAD2",
  oldlace: "#FDF5E6",
  red: "#FF0000",
  fuchsia: "#FF00FF",
  magenta: "#FF00FF",
  deeppink: "#FF1493",
  orangered: "#FF4500",
  tomato: "#FF6347",
  hotpink: "#FF69B4",
  coral: "#FF7F50",
  darkorange: "#FF8C00",
  lightsalmon: "#FFA07A",
  orange: "#FFA500",
  lightpink: "#FFB6C1",
  pink: "#FFC0CB",
  gold: "#FFD700",
  peachpuff: "#FFDAB9",
  navajowhite: "#FFDEAD",
  moccasin: "#FFE4B5",
  bisque: "#FFE4C4",
  mistyrose: "#FFE4E1",
  blanchedalmond: "#FFEBCD",
  papayawhip: "#FFEFD5",
  lavenderblush: "#FFF0F5",
  seashell: "#FFF5EE",
  cornsilk: "#FFF8DC",
  lemonchiffon: "#FFFACD",
  floralwhite: "#FFFAF0",
  snow: "#FFFAFA",
  yellow: "#FFFF00",
  lightyellow: "#FFFFE0",
  ivory: "#FFFFF0",
  white: "#FFFFFF",
};

/**
 * @param {number} [pixelRatio=1]
 */
class ColorPicker {
  /**
   * @param {number} [pixelRatio=1]
   */
  constructor(pixelRatio = 1) {
    this.pixelRatio = pixelRatio;
    this.generated = false;
    this.centerCoordinates = { x: 289 / 2, y: 289 / 2 };
    this.r = 289 * 0.49;
    this.color = { r: 255, g: 255, b: 255, a: 1.0 };
    this.hueCircle = undefined;
    this.initialColor = { r: 255, g: 255, b: 255, a: 1.0 };
    this.previousColor = undefined;
    this.applied = false;

    // bound by
    this.updateCallback = () => {};
    this.closeCallback = () => {};

    // create all DOM elements
    this._create();
  }

  /**
   * this inserts the colorPicker into a div from the DOM
   *
   * @param {Element} container
   */
  insertTo(container) {
    if (this.hammer !== undefined) {
      this.hammer.destroy();
      this.hammer = undefined;
    }
    this.container = container;
    this.container.appendChild(this.frame);
    this._bindHammer();

    this._setSize();
  }

  /**
   * the callback is executed on apply and save. Bind it to the application
   *
   * @param {Function} callback
   */
  setUpdateCallback(callback) {
    if (typeof callback === "function") {
      this.updateCallback = callback;
    } else {
      throw new Error(
        "Function attempted to set as colorPicker update callback is not a function."
      );
    }
  }

  /**
   * the callback is executed on apply and save. Bind it to the application
   *
   * @param {Function} callback
   */
  setCloseCallback(callback) {
    if (typeof callback === "function") {
      this.closeCallback = callback;
    } else {
      throw new Error(
        "Function attempted to set as colorPicker closing callback is not a function."
      );
    }
  }

  /**
   *
   * @param {string} color
   * @returns {string}
   * @private
   */
  _isColorString(color) {
    if (typeof color === "string") {
      return htmlColors[color];
    }
  }

  /**
   * Set the color of the colorPicker
   * Supported formats:
   * 'red'                   --> HTML color string
   * '#ffffff'               --> hex string
   * 'rgb(255,255,255)'      --> rgb string
   * 'rgba(255,255,255,1.0)' --> rgba string
   * {r:255,g:255,b:255}     --> rgb object
   * {r:255,g:255,b:255,a:1.0} --> rgba object
   *
   * @param {string | object} color
   * @param {boolean} [setInitial=true]
   */
  setColor(color, setInitial = true) {
    if (color === "none") {
      return;
    }

    let rgba;

    // if a html color shorthand is used, convert to hex
    const htmlColor = this._isColorString(color);
    if (htmlColor !== undefined) {
      color = htmlColor;
    }

    // check format
    if (isString(color) === true) {
      if (isValidRGB(color) === true) {
        const rgbaArray = color
          .substr(4)
          .substr(0, color.length - 5)
          .split(",");
        rgba = { r: rgbaArray[0], g: rgbaArray[1], b: rgbaArray[2], a: 1.0 };
      } else if (isValidRGBA(color) === true) {
        const rgbaArray = color
          .substr(5)
          .substr(0, color.length - 6)
          .split(",");
        rgba = {
          r: rgbaArray[0],
          g: rgbaArray[1],
          b: rgbaArray[2],
          a: rgbaArray[3],
        };
      } else if (isValidHex(color) === true) {
        const rgbObj = hexToRGB(color);
        rgba = { r: rgbObj.r, g: rgbObj.g, b: rgbObj.b, a: 1.0 };
      }
    } else {
      if (color instanceof Object) {
        if (
          color.r !== undefined &&
          color.g !== undefined &&
          color.b !== undefined
        ) {
          const alpha = color.a !== undefined ? color.a : "1.0";
          rgba = { r: color.r, g: color.g, b: color.b, a: alpha };
        }
      }
    }

    // set color
    if (rgba === undefined) {
      throw new Error(
        "Unknown color passed to the colorPicker. Supported are strings: rgb, hex, rgba. Object: rgb ({r:r,g:g,b:b,[a:a]}). Supplied: " +
          JSON.stringify(color)
      );
    } else {
      this._setColor(rgba, setInitial);
    }
  }

  /**
   * this shows the color picker.
   * The hue circle is constructed once and stored.
   */
  show() {
    if (this.closeCallback !== undefined) {
      this.closeCallback();
      this.closeCallback = undefined;
    }

    this.applied = false;
    this.frame.style.display = "block";
    this._generateHueCircle();
  }

  // ------------------------------------------ PRIVATE ----------------------------- //

  /**
   * Hide the picker. Is called by the cancel button.
   * Optional boolean to store the previous color for easy access later on.
   *
   * @param {boolean} [storePrevious=true]
   * @private
   */
  _hide(storePrevious = true) {
    // store the previous color for next time;
    if (storePrevious === true) {
      this.previousColor = Object.assign({}, this.color);
    }

    if (this.applied === true) {
      this.updateCallback(this.initialColor);
    }

    this.frame.style.display = "none";

    // call the closing callback, restoring the onclick method.
    // this is in a setTimeout because it will trigger the show again before the click is done.
    setTimeout(() => {
      if (this.closeCallback !== undefined) {
        this.closeCallback();
        this.closeCallback = undefined;
      }
    }, 0);
  }

  /**
   * bound to the save button. Saves and hides.
   *
   * @private
   */
  _save() {
    this.updateCallback(this.color);
    this.applied = false;
    this._hide();
  }

  /**
   * Bound to apply button. Saves but does not close. Is undone by the cancel button.
   *
   * @private
   */
  _apply() {
    this.applied = true;
    this.updateCallback(this.color);
    this._updatePicker(this.color);
  }

  /**
   * load the color from the previous session.
   *
   * @private
   */
  _loadLast() {
    if (this.previousColor !== undefined) {
      this.setColor(this.previousColor, false);
    } else {
      alert("There is no last color to load...");
    }
  }

  /**
   * set the color, place the picker
   *
   * @param {object} rgba
   * @param {boolean} [setInitial=true]
   * @private
   */
  _setColor(rgba, setInitial = true) {
    // store the initial color
    if (setInitial === true) {
      this.initialColor = Object.assign({}, rgba);
    }

    this.color = rgba;
    const hsv = RGBToHSV(rgba.r, rgba.g, rgba.b);

    const angleConvert = 2 * Math.PI;
    const radius = this.r * hsv.s;
    const x =
      this.centerCoordinates.x + radius * Math.sin(angleConvert * hsv.h);
    const y =
      this.centerCoordinates.y + radius * Math.cos(angleConvert * hsv.h);

    this.colorPickerSelector.style.left =
      x - 0.5 * this.colorPickerSelector.clientWidth + "px";
    this.colorPickerSelector.style.top =
      y - 0.5 * this.colorPickerSelector.clientHeight + "px";

    this._updatePicker(rgba);
  }

  /**
   * bound to opacity control
   *
   * @param {number} value
   * @private
   */
  _setOpacity(value) {
    this.color.a = value / 100;
    this._updatePicker(this.color);
  }

  /**
   * bound to brightness control
   *
   * @param {number} value
   * @private
   */
  _setBrightness(value) {
    const hsv = RGBToHSV(this.color.r, this.color.g, this.color.b);
    hsv.v = value / 100;
    const rgba = HSVToRGB(hsv.h, hsv.s, hsv.v);
    rgba["a"] = this.color.a;
    this.color = rgba;
    this._updatePicker();
  }

  /**
   * update the color picker. A black circle overlays the hue circle to mimic the brightness decreasing.
   *
   * @param {object} rgba
   * @private
   */
  _updatePicker(rgba = this.color) {
    const hsv = RGBToHSV(rgba.r, rgba.g, rgba.b);
    const ctx = this.colorPickerCanvas.getContext("2d");
    if (this.pixelRation === undefined) {
      this.pixelRatio =
        (window.devicePixelRatio || 1) /
        (ctx.webkitBackingStorePixelRatio ||
          ctx.mozBackingStorePixelRatio ||
          ctx.msBackingStorePixelRatio ||
          ctx.oBackingStorePixelRatio ||
          ctx.backingStorePixelRatio ||
          1);
    }
    ctx.setTransform(this.pixelRatio, 0, 0, this.pixelRatio, 0, 0);

    // clear the canvas
    const w = this.colorPickerCanvas.clientWidth;
    const h = this.colorPickerCanvas.clientHeight;
    ctx.clearRect(0, 0, w, h);

    ctx.putImageData(this.hueCircle, 0, 0);
    ctx.fillStyle = "rgba(0,0,0," + (1 - hsv.v) + ")";
    ctx.circle(this.centerCoordinates.x, this.centerCoordinates.y, this.r);
    ctx.fill();

    this.brightnessRange.value = 100 * hsv.v;
    this.opacityRange.value = 100 * rgba.a;

    this.initialColorDiv.style.backgroundColor =
      "rgba(" +
      this.initialColor.r +
      "," +
      this.initialColor.g +
      "," +
      this.initialColor.b +
      "," +
      this.initialColor.a +
      ")";
    this.newColorDiv.style.backgroundColor =
      "rgba(" +
      this.color.r +
      "," +
      this.color.g +
      "," +
      this.color.b +
      "," +
      this.color.a +
      ")";
  }

  /**
   * used by create to set the size of the canvas.
   *
   * @private
   */
  _setSize() {
    this.colorPickerCanvas.style.width = "100%";
    this.colorPickerCanvas.style.height = "100%";

    this.colorPickerCanvas.width = 289 * this.pixelRatio;
    this.colorPickerCanvas.height = 289 * this.pixelRatio;
  }

  /**
   * create all dom elements
   * TODO: cleanup, lots of similar dom elements
   *
   * @private
   */
  _create() {
    this.frame = document.createElement("div");
    this.frame.className = "vis-color-picker";

    this.colorPickerDiv = document.createElement("div");
    this.colorPickerSelector = document.createElement("div");
    this.colorPickerSelector.className = "vis-selector";
    this.colorPickerDiv.appendChild(this.colorPickerSelector);

    this.colorPickerCanvas = document.createElement("canvas");
    this.colorPickerDiv.appendChild(this.colorPickerCanvas);

    if (!this.colorPickerCanvas.getContext) {
      const noCanvas = document.createElement("DIV");
      noCanvas.style.color = "red";
      noCanvas.style.fontWeight = "bold";
      noCanvas.style.padding = "10px";
      noCanvas.innerText = "Error: your browser does not support HTML canvas";
      this.colorPickerCanvas.appendChild(noCanvas);
    } else {
      const ctx = this.colorPickerCanvas.getContext("2d");
      this.pixelRatio =
        (window.devicePixelRatio || 1) /
        (ctx.webkitBackingStorePixelRatio ||
          ctx.mozBackingStorePixelRatio ||
          ctx.msBackingStorePixelRatio ||
          ctx.oBackingStorePixelRatio ||
          ctx.backingStorePixelRatio ||
          1);
      this.colorPickerCanvas
        .getContext("2d")
        .setTransform(this.pixelRatio, 0, 0, this.pixelRatio, 0, 0);
    }

    this.colorPickerDiv.className = "vis-color";

    this.opacityDiv = document.createElement("div");
    this.opacityDiv.className = "vis-opacity";

    this.brightnessDiv = document.createElement("div");
    this.brightnessDiv.className = "vis-brightness";

    this.arrowDiv = document.createElement("div");
    this.arrowDiv.className = "vis-arrow";

    this.opacityRange = document.createElement("input");
    try {
      this.opacityRange.type = "range"; // Not supported on IE9
      this.opacityRange.min = "0";
      this.opacityRange.max = "100";
    } catch (err) {
      // TODO: Add some error handling.
    }
    this.opacityRange.value = "100";
    this.opacityRange.className = "vis-range";

    this.brightnessRange = document.createElement("input");
    try {
      this.brightnessRange.type = "range"; // Not supported on IE9
      this.brightnessRange.min = "0";
      this.brightnessRange.max = "100";
    } catch (err) {
      // TODO: Add some error handling.
    }
    this.brightnessRange.value = "100";
    this.brightnessRange.className = "vis-range";

    this.opacityDiv.appendChild(this.opacityRange);
    this.brightnessDiv.appendChild(this.brightnessRange);

    const me = this;
    this.opacityRange.onchange = function () {
      me._setOpacity(this.value);
    };
    this.opacityRange.oninput = function () {
      me._setOpacity(this.value);
    };
    this.brightnessRange.onchange = function () {
      me._setBrightness(this.value);
    };
    this.brightnessRange.oninput = function () {
      me._setBrightness(this.value);
    };

    this.brightnessLabel = document.createElement("div");
    this.brightnessLabel.className = "vis-label vis-brightness";
    this.brightnessLabel.innerText = "brightness:";

    this.opacityLabel = document.createElement("div");
    this.opacityLabel.className = "vis-label vis-opacity";
    this.opacityLabel.innerText = "opacity:";

    this.newColorDiv = document.createElement("div");
    this.newColorDiv.className = "vis-new-color";
    this.newColorDiv.innerText = "new";

    this.initialColorDiv = document.createElement("div");
    this.initialColorDiv.className = "vis-initial-color";
    this.initialColorDiv.innerText = "initial";

    this.cancelButton = document.createElement("div");
    this.cancelButton.className = "vis-button vis-cancel";
    this.cancelButton.innerText = "cancel";
    this.cancelButton.onclick = this._hide.bind(this, false);

    this.applyButton = document.createElement("div");
    this.applyButton.className = "vis-button vis-apply";
    this.applyButton.innerText = "apply";
    this.applyButton.onclick = this._apply.bind(this);

    this.saveButton = document.createElement("div");
    this.saveButton.className = "vis-button vis-save";
    this.saveButton.innerText = "save";
    this.saveButton.onclick = this._save.bind(this);

    this.loadButton = document.createElement("div");
    this.loadButton.className = "vis-button vis-load";
    this.loadButton.innerText = "load last";
    this.loadButton.onclick = this._loadLast.bind(this);

    this.frame.appendChild(this.colorPickerDiv);
    this.frame.appendChild(this.arrowDiv);
    this.frame.appendChild(this.brightnessLabel);
    this.frame.appendChild(this.brightnessDiv);
    this.frame.appendChild(this.opacityLabel);
    this.frame.appendChild(this.opacityDiv);
    this.frame.appendChild(this.newColorDiv);
    this.frame.appendChild(this.initialColorDiv);

    this.frame.appendChild(this.cancelButton);
    this.frame.appendChild(this.applyButton);
    this.frame.appendChild(this.saveButton);
    this.frame.appendChild(this.loadButton);
  }

  /**
   * bind hammer to the color picker
   *
   * @private
   */
  _bindHammer() {
    this.drag = {};
    this.pinch = {};
    this.hammer = new Hammer$1(this.colorPickerCanvas);
    this.hammer.get("pinch").set({ enable: true });

    this.hammer.on("hammer.input", (event) => {
      if (event.isFirst) {
        this._moveSelector(event);
      }
    });
    this.hammer.on("tap", (event) => {
      this._moveSelector(event);
    });
    this.hammer.on("panstart", (event) => {
      this._moveSelector(event);
    });
    this.hammer.on("panmove", (event) => {
      this._moveSelector(event);
    });
    this.hammer.on("panend", (event) => {
      this._moveSelector(event);
    });
  }

  /**
   * generate the hue circle. This is relatively heavy (200ms) and is done only once on the first time it is shown.
   *
   * @private
   */
  _generateHueCircle() {
    if (this.generated === false) {
      const ctx = this.colorPickerCanvas.getContext("2d");
      if (this.pixelRation === undefined) {
        this.pixelRatio =
          (window.devicePixelRatio || 1) /
          (ctx.webkitBackingStorePixelRatio ||
            ctx.mozBackingStorePixelRatio ||
            ctx.msBackingStorePixelRatio ||
            ctx.oBackingStorePixelRatio ||
            ctx.backingStorePixelRatio ||
            1);
      }
      ctx.setTransform(this.pixelRatio, 0, 0, this.pixelRatio, 0, 0);

      // clear the canvas
      const w = this.colorPickerCanvas.clientWidth;
      const h = this.colorPickerCanvas.clientHeight;
      ctx.clearRect(0, 0, w, h);

      // draw hue circle
      let x, y, hue, sat;
      this.centerCoordinates = { x: w * 0.5, y: h * 0.5 };
      this.r = 0.49 * w;
      const angleConvert = (2 * Math.PI) / 360;
      const hfac = 1 / 360;
      const sfac = 1 / this.r;
      let rgb;
      for (hue = 0; hue < 360; hue++) {
        for (sat = 0; sat < this.r; sat++) {
          x = this.centerCoordinates.x + sat * Math.sin(angleConvert * hue);
          y = this.centerCoordinates.y + sat * Math.cos(angleConvert * hue);
          rgb = HSVToRGB(hue * hfac, sat * sfac, 1);
          ctx.fillStyle = "rgb(" + rgb.r + "," + rgb.g + "," + rgb.b + ")";
          ctx.fillRect(x - 0.5, y - 0.5, 2, 2);
        }
      }
      ctx.strokeStyle = "rgba(0,0,0,1)";
      ctx.circle(this.centerCoordinates.x, this.centerCoordinates.y, this.r);
      ctx.stroke();

      this.hueCircle = ctx.getImageData(0, 0, w, h);
    }
    this.generated = true;
  }

  /**
   * move the selector. This is called by hammer functions.
   *
   * @param {Event}  event   The event
   * @private
   */
  _moveSelector(event) {
    const rect = this.colorPickerDiv.getBoundingClientRect();
    const left = event.center.x - rect.left;
    const top = event.center.y - rect.top;

    const centerY = 0.5 * this.colorPickerDiv.clientHeight;
    const centerX = 0.5 * this.colorPickerDiv.clientWidth;

    const x = left - centerX;
    const y = top - centerY;

    const angle = Math.atan2(x, y);
    const radius = 0.98 * Math.min(Math.sqrt(x * x + y * y), centerX);

    const newTop = Math.cos(angle) * radius + centerY;
    const newLeft = Math.sin(angle) * radius + centerX;

    this.colorPickerSelector.style.top =
      newTop - 0.5 * this.colorPickerSelector.clientHeight + "px";
    this.colorPickerSelector.style.left =
      newLeft - 0.5 * this.colorPickerSelector.clientWidth + "px";

    // set color
    let h = angle / (2 * Math.PI);
    h = h < 0 ? h + 1 : h;
    const s = radius / this.r;
    const hsv = RGBToHSV(this.color.r, this.color.g, this.color.b);
    hsv.h = h;
    hsv.s = s;
    const rgba = HSVToRGB(hsv.h, hsv.s, hsv.v);
    rgba["a"] = this.color.a;
    this.color = rgba;

    // update previews
    this.initialColorDiv.style.backgroundColor =
      "rgba(" +
      this.initialColor.r +
      "," +
      this.initialColor.g +
      "," +
      this.initialColor.b +
      "," +
      this.initialColor.a +
      ")";
    this.newColorDiv.style.backgroundColor =
      "rgba(" +
      this.color.r +
      "," +
      this.color.g +
      "," +
      this.color.b +
      "," +
      this.color.a +
      ")";
  }
}

/**
 * Wrap given text (last argument) in HTML elements (all preceding arguments).
 *
 * @param {...any} rest - List of tag names followed by inner text.
 *
 * @returns An element or a text node.
 */
function wrapInTag(...rest) {
  if (rest.length < 1) {
    throw new TypeError("Invalid arguments.");
  } else if (rest.length === 1) {
    return document.createTextNode(rest[0]);
  } else {
    const element = document.createElement(rest[0]);
    element.appendChild(wrapInTag(...rest.slice(1)));
    return element;
  }
}

/**
 * The way this works is for all properties of this.possible options, you can supply the property name in any form to list the options.
 * Boolean options are recognised as Boolean
 * Number options should be written as array: [default value, min value, max value, stepsize]
 * Colors should be written as array: ['color', '#ffffff']
 * Strings with should be written as array: [option1, option2, option3, ..]
 *
 * The options are matched with their counterparts in each of the modules and the values used in the configuration are
 */
class Configurator {
  /**
   * @param {object} parentModule        | the location where parentModule.setOptions() can be called
   * @param {object} defaultContainer    | the default container of the module
   * @param {object} configureOptions    | the fully configured and predefined options set found in allOptions.js
   * @param {number} pixelRatio          | canvas pixel ratio
   * @param {Function} hideOption        | custom logic to dynamically hide options
   */
  constructor(
    parentModule,
    defaultContainer,
    configureOptions,
    pixelRatio = 1,
    hideOption = () => false
  ) {
    this.parent = parentModule;
    this.changedOptions = [];
    this.container = defaultContainer;
    this.allowCreation = false;
    this.hideOption = hideOption;

    this.options = {};
    this.initialized = false;
    this.popupCounter = 0;
    this.defaultOptions = {
      enabled: false,
      filter: true,
      container: undefined,
      showButton: true,
    };
    Object.assign(this.options, this.defaultOptions);

    this.configureOptions = configureOptions;
    this.moduleOptions = {};
    this.domElements = [];
    this.popupDiv = {};
    this.popupLimit = 5;
    this.popupHistory = {};
    this.colorPicker = new ColorPicker(pixelRatio);
    this.wrapper = undefined;
  }

  /**
   * refresh all options.
   * Because all modules parse their options by themselves, we just use their options. We copy them here.
   *
   * @param {object} options
   */
  setOptions(options) {
    if (options !== undefined) {
      // reset the popup history because the indices may have been changed.
      this.popupHistory = {};
      this._removePopup();

      let enabled = true;
      if (typeof options === "string") {
        this.options.filter = options;
      } else if (Array.isArray(options)) {
        this.options.filter = options.join();
      } else if (typeof options === "object") {
        if (options == null) {
          throw new TypeError("options cannot be null");
        }
        if (options.container !== undefined) {
          this.options.container = options.container;
        }
        if (options.filter !== undefined) {
          this.options.filter = options.filter;
        }
        if (options.showButton !== undefined) {
          this.options.showButton = options.showButton;
        }
        if (options.enabled !== undefined) {
          enabled = options.enabled;
        }
      } else if (typeof options === "boolean") {
        this.options.filter = true;
        enabled = options;
      } else if (typeof options === "function") {
        this.options.filter = options;
        enabled = true;
      }
      if (this.options.filter === false) {
        enabled = false;
      }

      this.options.enabled = enabled;
    }
    this._clean();
  }

  /**
   *
   * @param {object} moduleOptions
   */
  setModuleOptions(moduleOptions) {
    this.moduleOptions = moduleOptions;
    if (this.options.enabled === true) {
      this._clean();
      if (this.options.container !== undefined) {
        this.container = this.options.container;
      }
      this._create();
    }
  }

  /**
   * Create all DOM elements
   *
   * @private
   */
  _create() {
    this._clean();
    this.changedOptions = [];

    const filter = this.options.filter;
    let counter = 0;
    let show = false;
    for (const option in this.configureOptions) {
      if (Object.prototype.hasOwnProperty.call(this.configureOptions, option)) {
        this.allowCreation = false;
        show = false;
        if (typeof filter === "function") {
          show = filter(option, []);
          show =
            show ||
            this._handleObject(this.configureOptions[option], [option], true);
        } else if (filter === true || filter.indexOf(option) !== -1) {
          show = true;
        }

        if (show !== false) {
          this.allowCreation = true;

          // linebreak between categories
          if (counter > 0) {
            this._makeItem([]);
          }
          // a header for the category
          this._makeHeader(option);

          // get the sub options
          this._handleObject(this.configureOptions[option], [option]);
        }
        counter++;
      }
    }
    this._makeButton();
    this._push();
    //~ this.colorPicker.insertTo(this.container);
  }

  /**
   * draw all DOM elements on the screen
   *
   * @private
   */
  _push() {
    this.wrapper = document.createElement("div");
    this.wrapper.className = "vis-configuration-wrapper";
    this.container.appendChild(this.wrapper);
    for (let i = 0; i < this.domElements.length; i++) {
      this.wrapper.appendChild(this.domElements[i]);
    }

    this._showPopupIfNeeded();
  }

  /**
   * delete all DOM elements
   *
   * @private
   */
  _clean() {
    for (let i = 0; i < this.domElements.length; i++) {
      this.wrapper.removeChild(this.domElements[i]);
    }

    if (this.wrapper !== undefined) {
      this.container.removeChild(this.wrapper);
      this.wrapper = undefined;
    }
    this.domElements = [];

    this._removePopup();
  }

  /**
   * get the value from the actualOptions if it exists
   *
   * @param {Array} path    | where to look for the actual option
   * @returns {*}
   * @private
   */
  _getValue(path) {
    let base = this.moduleOptions;
    for (let i = 0; i < path.length; i++) {
      if (base[path[i]] !== undefined) {
        base = base[path[i]];
      } else {
        base = undefined;
        break;
      }
    }
    return base;
  }

  /**
   * all option elements are wrapped in an item
   *
   * @param {Array} path    | where to look for the actual option
   * @param {Array.<Element>} domElements
   * @returns {number}
   * @private
   */
  _makeItem(path, ...domElements) {
    if (this.allowCreation === true) {
      const item = document.createElement("div");
      item.className =
        "vis-configuration vis-config-item vis-config-s" + path.length;
      domElements.forEach((element) => {
        item.appendChild(element);
      });
      this.domElements.push(item);
      return this.domElements.length;
    }
    return 0;
  }

  /**
   * header for major subjects
   *
   * @param {string} name
   * @private
   */
  _makeHeader(name) {
    const div = document.createElement("div");
    div.className = "vis-configuration vis-config-header";
    div.innerText = name;
    this._makeItem([], div);
  }

  /**
   * make a label, if it is an object label, it gets different styling.
   *
   * @param {string} name
   * @param {Array} path    | where to look for the actual option
   * @param {string} objectLabel
   * @returns {HTMLElement}
   * @private
   */
  _makeLabel(name, path, objectLabel = false) {
    const div = document.createElement("div");
    div.className =
      "vis-configuration vis-config-label vis-config-s" + path.length;
    if (objectLabel === true) {
      while (div.firstChild) {
        div.removeChild(div.firstChild);
      }
      div.appendChild(wrapInTag("i", "b", name));
    } else {
      div.innerText = name + ":";
    }
    return div;
  }

  /**
   * make a dropdown list for multiple possible string optoins
   *
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _makeDropdown(arr, value, path) {
    const select = document.createElement("select");
    select.className = "vis-configuration vis-config-select";
    let selectedValue = 0;
    if (value !== undefined) {
      if (arr.indexOf(value) !== -1) {
        selectedValue = arr.indexOf(value);
      }
    }

    for (let i = 0; i < arr.length; i++) {
      const option = document.createElement("option");
      option.value = arr[i];
      if (i === selectedValue) {
        option.selected = "selected";
      }
      option.innerText = arr[i];
      select.appendChild(option);
    }

    const me = this;
    select.onchange = function () {
      me._update(this.value, path);
    };

    const label = this._makeLabel(path[path.length - 1], path);
    this._makeItem(path, label, select);
  }

  /**
   * make a range object for numeric options
   *
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _makeRange(arr, value, path) {
    const defaultValue = arr[0];
    const min = arr[1];
    const max = arr[2];
    const step = arr[3];
    const range = document.createElement("input");
    range.className = "vis-configuration vis-config-range";
    try {
      range.type = "range"; // not supported on IE9
      range.min = min;
      range.max = max;
    } catch (err) {
      // TODO: Add some error handling.
    }
    range.step = step;

    // set up the popup settings in case they are needed.
    let popupString = "";
    let popupValue = 0;

    if (value !== undefined) {
      const factor = 1.2;
      if (value < 0 && value * factor < min) {
        range.min = Math.ceil(value * factor);
        popupValue = range.min;
        popupString = "range increased";
      } else if (value / factor < min) {
        range.min = Math.ceil(value / factor);
        popupValue = range.min;
        popupString = "range increased";
      }
      if (value * factor > max && max !== 1) {
        range.max = Math.ceil(value * factor);
        popupValue = range.max;
        popupString = "range increased";
      }
      range.value = value;
    } else {
      range.value = defaultValue;
    }

    const input = document.createElement("input");
    input.className = "vis-configuration vis-config-rangeinput";
    input.value = range.value;

    const me = this;
    range.onchange = function () {
      input.value = this.value;
      me._update(Number(this.value), path);
    };
    range.oninput = function () {
      input.value = this.value;
    };

    const label = this._makeLabel(path[path.length - 1], path);
    const itemIndex = this._makeItem(path, label, range, input);

    // if a popup is needed AND it has not been shown for this value, show it.
    if (popupString !== "" && this.popupHistory[itemIndex] !== popupValue) {
      this.popupHistory[itemIndex] = popupValue;
      this._setupPopup(popupString, itemIndex);
    }
  }

  /**
   * make a button object
   *
   * @private
   */
  _makeButton() {
    if (this.options.showButton === true) {
      const generateButton = document.createElement("div");
      generateButton.className = "vis-configuration vis-config-button";
      generateButton.innerText = "generate options";
      generateButton.onclick = () => {
        this._printOptions();
      };
      generateButton.onmouseover = () => {
        generateButton.className = "vis-configuration vis-config-button hover";
      };
      generateButton.onmouseout = () => {
        generateButton.className = "vis-configuration vis-config-button";
      };

      this.optionsContainer = document.createElement("div");
      this.optionsContainer.className =
        "vis-configuration vis-config-option-container";

      this.domElements.push(this.optionsContainer);
      this.domElements.push(generateButton);
    }
  }

  /**
   * prepare the popup
   *
   * @param {string} string
   * @param {number} index
   * @private
   */
  _setupPopup(string, index) {
    if (
      this.initialized === true &&
      this.allowCreation === true &&
      this.popupCounter < this.popupLimit
    ) {
      const div = document.createElement("div");
      div.id = "vis-configuration-popup";
      div.className = "vis-configuration-popup";
      div.innerText = string;
      div.onclick = () => {
        this._removePopup();
      };
      this.popupCounter += 1;
      this.popupDiv = { html: div, index: index };
    }
  }

  /**
   * remove the popup from the dom
   *
   * @private
   */
  _removePopup() {
    if (this.popupDiv.html !== undefined) {
      this.popupDiv.html.parentNode.removeChild(this.popupDiv.html);
      clearTimeout(this.popupDiv.hideTimeout);
      clearTimeout(this.popupDiv.deleteTimeout);
      this.popupDiv = {};
    }
  }

  /**
   * Show the popup if it is needed.
   *
   * @private
   */
  _showPopupIfNeeded() {
    if (this.popupDiv.html !== undefined) {
      const correspondingElement = this.domElements[this.popupDiv.index];
      const rect = correspondingElement.getBoundingClientRect();
      this.popupDiv.html.style.left = rect.left + "px";
      this.popupDiv.html.style.top = rect.top - 30 + "px"; // 30 is the height;
      document.body.appendChild(this.popupDiv.html);
      this.popupDiv.hideTimeout = setTimeout(() => {
        this.popupDiv.html.style.opacity = 0;
      }, 1500);
      this.popupDiv.deleteTimeout = setTimeout(() => {
        this._removePopup();
      }, 1800);
    }
  }

  /**
   * make a checkbox for boolean options.
   *
   * @param {number} defaultValue
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _makeCheckbox(defaultValue, value, path) {
    const checkbox = document.createElement("input");
    checkbox.type = "checkbox";
    checkbox.className = "vis-configuration vis-config-checkbox";
    checkbox.checked = defaultValue;
    if (value !== undefined) {
      checkbox.checked = value;
      if (value !== defaultValue) {
        if (typeof defaultValue === "object") {
          if (value !== defaultValue.enabled) {
            this.changedOptions.push({ path: path, value: value });
          }
        } else {
          this.changedOptions.push({ path: path, value: value });
        }
      }
    }

    const me = this;
    checkbox.onchange = function () {
      me._update(this.checked, path);
    };

    const label = this._makeLabel(path[path.length - 1], path);
    this._makeItem(path, label, checkbox);
  }

  /**
   * make a text input field for string options.
   *
   * @param {number} defaultValue
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _makeTextInput(defaultValue, value, path) {
    const checkbox = document.createElement("input");
    checkbox.type = "text";
    checkbox.className = "vis-configuration vis-config-text";
    checkbox.value = value;
    if (value !== defaultValue) {
      this.changedOptions.push({ path: path, value: value });
    }

    const me = this;
    checkbox.onchange = function () {
      me._update(this.value, path);
    };

    const label = this._makeLabel(path[path.length - 1], path);
    this._makeItem(path, label, checkbox);
  }

  /**
   * make a color field with a color picker for color fields
   *
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _makeColorField(arr, value, path) {
    const defaultColor = arr[1];
    const div = document.createElement("div");
    value = value === undefined ? defaultColor : value;

    if (value !== "none") {
      div.className = "vis-configuration vis-config-colorBlock";
      div.style.backgroundColor = value;
    } else {
      div.className = "vis-configuration vis-config-colorBlock none";
    }

    value = value === undefined ? defaultColor : value;
    div.onclick = () => {
      this._showColorPicker(value, div, path);
    };

    const label = this._makeLabel(path[path.length - 1], path);
    this._makeItem(path, label, div);
  }

  /**
   * used by the color buttons to call the color picker.
   *
   * @param {number} value
   * @param {HTMLElement} div
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _showColorPicker(value, div, path) {
    // clear the callback from this div
    div.onclick = function () {};

    this.colorPicker.insertTo(div);
    this.colorPicker.show();

    this.colorPicker.setColor(value);
    this.colorPicker.setUpdateCallback((color) => {
      const colorString =
        "rgba(" + color.r + "," + color.g + "," + color.b + "," + color.a + ")";
      div.style.backgroundColor = colorString;
      this._update(colorString, path);
    });

    // on close of the colorpicker, restore the callback.
    this.colorPicker.setCloseCallback(() => {
      div.onclick = () => {
        this._showColorPicker(value, div, path);
      };
    });
  }

  /**
   * parse an object and draw the correct items
   *
   * @param {object} obj
   * @param {Array} [path=[]]    | where to look for the actual option
   * @param {boolean} [checkOnly=false]
   * @returns {boolean}
   * @private
   */
  _handleObject(obj, path = [], checkOnly = false) {
    let show = false;
    const filter = this.options.filter;
    let visibleInSet = false;
    for (const subObj in obj) {
      if (Object.prototype.hasOwnProperty.call(obj, subObj)) {
        show = true;
        const item = obj[subObj];
        const newPath = copyAndExtendArray(path, subObj);
        if (typeof filter === "function") {
          show = filter(subObj, path);

          // if needed we must go deeper into the object.
          if (show === false) {
            if (
              !Array.isArray(item) &&
              typeof item !== "string" &&
              typeof item !== "boolean" &&
              item instanceof Object
            ) {
              this.allowCreation = false;
              show = this._handleObject(item, newPath, true);
              this.allowCreation = checkOnly === false;
            }
          }
        }

        if (show !== false) {
          visibleInSet = true;
          const value = this._getValue(newPath);

          if (Array.isArray(item)) {
            this._handleArray(item, value, newPath);
          } else if (typeof item === "string") {
            this._makeTextInput(item, value, newPath);
          } else if (typeof item === "boolean") {
            this._makeCheckbox(item, value, newPath);
          } else if (item instanceof Object) {
            // skip the options that are not enabled
            if (!this.hideOption(path, subObj, this.moduleOptions)) {
              // initially collapse options with an disabled enabled option.
              if (item.enabled !== undefined) {
                const enabledPath = copyAndExtendArray(newPath, "enabled");
                const enabledValue = this._getValue(enabledPath);
                if (enabledValue === true) {
                  const label = this._makeLabel(subObj, newPath, true);
                  this._makeItem(newPath, label);
                  visibleInSet =
                    this._handleObject(item, newPath) || visibleInSet;
                } else {
                  this._makeCheckbox(item, enabledValue, newPath);
                }
              } else {
                const label = this._makeLabel(subObj, newPath, true);
                this._makeItem(newPath, label);
                visibleInSet =
                  this._handleObject(item, newPath) || visibleInSet;
              }
            }
          } else {
            console.error("dont know how to handle", item, subObj, newPath);
          }
        }
      }
    }
    return visibleInSet;
  }

  /**
   * handle the array type of option
   *
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _handleArray(arr, value, path) {
    if (typeof arr[0] === "string" && arr[0] === "color") {
      this._makeColorField(arr, value, path);
      if (arr[1] !== value) {
        this.changedOptions.push({ path: path, value: value });
      }
    } else if (typeof arr[0] === "string") {
      this._makeDropdown(arr, value, path);
      if (arr[0] !== value) {
        this.changedOptions.push({ path: path, value: value });
      }
    } else if (typeof arr[0] === "number") {
      this._makeRange(arr, value, path);
      if (arr[0] !== value) {
        this.changedOptions.push({ path: path, value: Number(value) });
      }
    }
  }

  /**
   * called to update the network with the new settings.
   *
   * @param {number} value
   * @param {Array} path    | where to look for the actual option
   * @private
   */
  _update(value, path) {
    const options = this._constructOptions(value, path);

    if (
      this.parent.body &&
      this.parent.body.emitter &&
      this.parent.body.emitter.emit
    ) {
      this.parent.body.emitter.emit("configChange", options);
    }
    this.initialized = true;
    this.parent.setOptions(options);
  }

  /**
   *
   * @param {string | boolean} value
   * @param {Array.<string>} path
   * @param {{}} optionsObj
   * @returns {{}}
   * @private
   */
  _constructOptions(value, path, optionsObj = {}) {
    let pointer = optionsObj;

    // when dropdown boxes can be string or boolean, we typecast it into correct types
    value = value === "true" ? true : value;
    value = value === "false" ? false : value;

    for (let i = 0; i < path.length; i++) {
      if (path[i] !== "global") {
        if (pointer[path[i]] === undefined) {
          pointer[path[i]] = {};
        }
        if (i !== path.length - 1) {
          pointer = pointer[path[i]];
        } else {
          pointer[path[i]] = value;
        }
      }
    }
    return optionsObj;
  }

  /**
   * @private
   */
  _printOptions() {
    const options = this.getOptions();

    while (this.optionsContainer.firstChild) {
      this.optionsContainer.removeChild(this.optionsContainer.firstChild);
    }
    this.optionsContainer.appendChild(
      wrapInTag("pre", "const options = " + JSON.stringify(options, null, 2))
    );
  }

  /**
   *
   * @returns {{}} options
   */
  getOptions() {
    const options = {};
    for (let i = 0; i < this.changedOptions.length; i++) {
      this._constructOptions(
        this.changedOptions[i].value,
        this.changedOptions[i].path,
        options
      );
    }
    return options;
  }
}

/**
 * Popup is a class to create a popup window with some text
 */
class Popup {
  /**
   * @param {Element} container       The container object.
   * @param {string}  overflowMethod  How the popup should act to overflowing ('flip' or 'cap')
   */
  constructor(container, overflowMethod) {
    this.container = container;
    this.overflowMethod = overflowMethod || "cap";

    this.x = 0;
    this.y = 0;
    this.padding = 5;
    this.hidden = false;

    // create the frame
    this.frame = document.createElement("div");
    this.frame.className = "vis-tooltip";
    this.container.appendChild(this.frame);
  }

  /**
   * @param {number} x   Horizontal position of the popup window
   * @param {number} y   Vertical position of the popup window
   */
  setPosition(x, y) {
    this.x = parseInt(x);
    this.y = parseInt(y);
  }

  /**
   * Set the content for the popup window. This can be HTML code or text.
   *
   * @param {string | Element} content
   */
  setText(content) {
    if (content instanceof Element) {
      while (this.frame.firstChild) {
        this.frame.removeChild(this.frame.firstChild);
      }
      this.frame.appendChild(content);
    } else {
      // String containing literal text, element has to be used for HTML due to
      // XSS risks associated with innerHTML (i.e. prevent XSS by accident).
      this.frame.innerText = content;
    }
  }

  /**
   * Show the popup window
   *
   * @param {boolean} [doShow]    Show or hide the window
   */
  show(doShow) {
    if (doShow === undefined) {
      doShow = true;
    }

    if (doShow === true) {
      const height = this.frame.clientHeight;
      const width = this.frame.clientWidth;
      const maxHeight = this.frame.parentNode.clientHeight;
      const maxWidth = this.frame.parentNode.clientWidth;

      let left = 0,
        top = 0;

      if (this.overflowMethod == "flip") {
        let isLeft = false,
          isTop = true; // Where around the position it's located

        if (this.y - height < this.padding) {
          isTop = false;
        }

        if (this.x + width > maxWidth - this.padding) {
          isLeft = true;
        }

        if (isLeft) {
          left = this.x - width;
        } else {
          left = this.x;
        }

        if (isTop) {
          top = this.y - height;
        } else {
          top = this.y;
        }
      } else {
        top = this.y - height;
        if (top + height + this.padding > maxHeight) {
          top = maxHeight - height - this.padding;
        }
        if (top < this.padding) {
          top = this.padding;
        }

        left = this.x;
        if (left + width + this.padding > maxWidth) {
          left = maxWidth - width - this.padding;
        }
        if (left < this.padding) {
          left = this.padding;
        }
      }

      this.frame.style.left = left + "px";
      this.frame.style.top = top + "px";
      this.frame.style.visibility = "visible";
      this.hidden = false;
    } else {
      this.hide();
    }
  }

  /**
   * Hide the popup window
   */
  hide() {
    this.hidden = true;
    this.frame.style.left = "0";
    this.frame.style.top = "0";
    this.frame.style.visibility = "hidden";
  }

  /**
   * Remove the popup window
   */
  destroy() {
    this.frame.parentNode.removeChild(this.frame); // Remove element from DOM
  }
}

let errorFound = false;
let allOptions;

const VALIDATOR_PRINT_STYLE = "background: #FFeeee; color: #dd0000";

/**
 *  Used to validate options.
 */
class Validator {
  /**
   * Main function to be called
   *
   * @param {object} options
   * @param {object} referenceOptions
   * @param {object} subObject
   * @returns {boolean}
   * @static
   */
  static validate(options, referenceOptions, subObject) {
    errorFound = false;
    allOptions = referenceOptions;
    let usedOptions = referenceOptions;
    if (subObject !== undefined) {
      usedOptions = referenceOptions[subObject];
    }
    Validator.parse(options, usedOptions, []);
    return errorFound;
  }

  /**
   * Will traverse an object recursively and check every value
   *
   * @param {object} options
   * @param {object} referenceOptions
   * @param {Array} path    | where to look for the actual option
   * @static
   */
  static parse(options, referenceOptions, path) {
    for (const option in options) {
      if (Object.prototype.hasOwnProperty.call(options, option)) {
        Validator.check(option, options, referenceOptions, path);
      }
    }
  }

  /**
   * Check every value. If the value is an object, call the parse function on that object.
   *
   * @param {string} option
   * @param {object} options
   * @param {object} referenceOptions
   * @param {Array} path    | where to look for the actual option
   * @static
   */
  static check(option, options, referenceOptions, path) {
    if (
      referenceOptions[option] === undefined &&
      referenceOptions.__any__ === undefined
    ) {
      Validator.getSuggestion(option, referenceOptions, path);
      return;
    }

    let referenceOption = option;
    let is_object = true;

    if (
      referenceOptions[option] === undefined &&
      referenceOptions.__any__ !== undefined
    ) {
      // NOTE: This only triggers if the __any__ is in the top level of the options object.
      //       THAT'S A REALLY BAD PLACE TO ALLOW IT!!!!
      // TODO: Examine if needed, remove if possible

      // __any__ is a wildcard. Any value is accepted and will be further analysed by reference.
      referenceOption = "__any__";

      // if the any-subgroup is not a predefined object in the configurator,
      // we do not look deeper into the object.
      is_object = Validator.getType(options[option]) === "object";
    }

    let refOptionObj = referenceOptions[referenceOption];
    if (is_object && refOptionObj.__type__ !== undefined) {
      refOptionObj = refOptionObj.__type__;
    }

    Validator.checkFields(
      option,
      options,
      referenceOptions,
      referenceOption,
      refOptionObj,
      path
    );
  }

  /**
   *
   * @param {string}  option           | the option property
   * @param {object}  options          | The supplied options object
   * @param {object}  referenceOptions | The reference options containing all options and their allowed formats
   * @param {string}  referenceOption  | Usually this is the same as option, except when handling an __any__ tag.
   * @param {string}  refOptionObj     | This is the type object from the reference options
   * @param {Array}   path             | where in the object is the option
   * @static
   */
  static checkFields(
    option,
    options,
    referenceOptions,
    referenceOption,
    refOptionObj,
    path
  ) {
    const log = function (message) {
      console.error(
        "%c" + message + Validator.printLocation(path, option),
        VALIDATOR_PRINT_STYLE
      );
    };

    const optionType = Validator.getType(options[option]);
    const refOptionType = refOptionObj[optionType];

    if (refOptionType !== undefined) {
      // if the type is correct, we check if it is supposed to be one of a few select values
      if (
        Validator.getType(refOptionType) === "array" &&
        refOptionType.indexOf(options[option]) === -1
      ) {
        log(
          'Invalid option detected in "' +
            option +
            '".' +
            " Allowed values are:" +
            Validator.print(refOptionType) +
            ' not "' +
            options[option] +
            '". '
        );
        errorFound = true;
      } else if (optionType === "object" && referenceOption !== "__any__") {
        path = copyAndExtendArray(path, option);
        Validator.parse(
          options[option],
          referenceOptions[referenceOption],
          path
        );
      }
    } else if (refOptionObj["any"] === undefined) {
      // type of the field is incorrect and the field cannot be any
      log(
        'Invalid type received for "' +
          option +
          '". Expected: ' +
          Validator.print(Object.keys(refOptionObj)) +
          ". Received [" +
          optionType +
          '] "' +
          options[option] +
          '"'
      );
      errorFound = true;
    }
  }

  /**
   *
   * @param {object | boolean | number | string | Array.<number> | Date | Node | Moment | undefined | null} object
   * @returns {string}
   * @static
   */
  static getType(object) {
    const type = typeof object;

    if (type === "object") {
      if (object === null) {
        return "null";
      }
      if (object instanceof Boolean) {
        return "boolean";
      }
      if (object instanceof Number) {
        return "number";
      }
      if (object instanceof String) {
        return "string";
      }
      if (Array.isArray(object)) {
        return "array";
      }
      if (object instanceof Date) {
        return "date";
      }
      if (object.nodeType !== undefined) {
        return "dom";
      }
      if (object._isAMomentObject === true) {
        return "moment";
      }
      return "object";
    } else if (type === "number") {
      return "number";
    } else if (type === "boolean") {
      return "boolean";
    } else if (type === "string") {
      return "string";
    } else if (type === undefined) {
      return "undefined";
    }
    return type;
  }

  /**
   * @param {string} option
   * @param {object} options
   * @param {Array.<string>} path
   * @static
   */
  static getSuggestion(option, options, path) {
    const localSearch = Validator.findInOptions(option, options, path, false);
    const globalSearch = Validator.findInOptions(option, allOptions, [], true);

    const localSearchThreshold = 8;
    const globalSearchThreshold = 4;

    let msg;
    if (localSearch.indexMatch !== undefined) {
      msg =
        " in " +
        Validator.printLocation(localSearch.path, option, "") +
        'Perhaps it was incomplete? Did you mean: "' +
        localSearch.indexMatch +
        '"?\n\n';
    } else if (
      globalSearch.distance <= globalSearchThreshold &&
      localSearch.distance > globalSearch.distance
    ) {
      msg =
        " in " +
        Validator.printLocation(localSearch.path, option, "") +
        "Perhaps it was misplaced? Matching option found at: " +
        Validator.printLocation(
          globalSearch.path,
          globalSearch.closestMatch,
          ""
        );
    } else if (localSearch.distance <= localSearchThreshold) {
      msg =
        '. Did you mean "' +
        localSearch.closestMatch +
        '"?' +
        Validator.printLocation(localSearch.path, option);
    } else {
      msg =
        ". Did you mean one of these: " +
        Validator.print(Object.keys(options)) +
        Validator.printLocation(path, option);
    }

    console.error(
      '%cUnknown option detected: "' + option + '"' + msg,
      VALIDATOR_PRINT_STYLE
    );
    errorFound = true;
  }

  /**
   * traverse the options in search for a match.
   *
   * @param {string} option
   * @param {object} options
   * @param {Array} path    | where to look for the actual option
   * @param {boolean} [recursive=false]
   * @returns {{closestMatch: string, path: Array, distance: number}}
   * @static
   */
  static findInOptions(option, options, path, recursive = false) {
    let min = 1e9;
    let closestMatch = "";
    let closestMatchPath = [];
    const lowerCaseOption = option.toLowerCase();
    let indexMatch = undefined;
    for (const op in options) {
      let distance;
      if (options[op].__type__ !== undefined && recursive === true) {
        const result = Validator.findInOptions(
          option,
          options[op],
          copyAndExtendArray(path, op)
        );
        if (min > result.distance) {
          closestMatch = result.closestMatch;
          closestMatchPath = result.path;
          min = result.distance;
          indexMatch = result.indexMatch;
        }
      } else {
        if (op.toLowerCase().indexOf(lowerCaseOption) !== -1) {
          indexMatch = op;
        }
        distance = Validator.levenshteinDistance(option, op);
        if (min > distance) {
          closestMatch = op;
          closestMatchPath = copyArray(path);
          min = distance;
        }
      }
    }
    return {
      closestMatch: closestMatch,
      path: closestMatchPath,
      distance: min,
      indexMatch: indexMatch,
    };
  }

  /**
   * @param {Array.<string>} path
   * @param {object} option
   * @param {string} prefix
   * @returns {string}
   * @static
   */
  static printLocation(path, option, prefix = "Problem value found at: \n") {
    let str = "\n\n" + prefix + "options = {\n";
    for (let i = 0; i < path.length; i++) {
      for (let j = 0; j < i + 1; j++) {
        str += "  ";
      }
      str += path[i] + ": {\n";
    }
    for (let j = 0; j < path.length + 1; j++) {
      str += "  ";
    }
    str += option + "\n";
    for (let i = 0; i < path.length + 1; i++) {
      for (let j = 0; j < path.length - i; j++) {
        str += "  ";
      }
      str += "}\n";
    }
    return str + "\n\n";
  }

  /**
   * @param {object} options
   * @returns {string}
   * @static
   */
  static print(options) {
    return JSON.stringify(options)
      .replace(/(")|(\[)|(\])|(,"__type__")/g, "")
      .replace(/(,)/g, ", ");
  }

  /**
   *  Compute the edit distance between the two given strings
   * http://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Levenshtein_distance#JavaScript
   *
   * Copyright (c) 2011 Andrei Mackenzie
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   * @param {string} a
   * @param {string} b
   * @returns {Array.<Array.<number>>}}
   * @static
   */
  static levenshteinDistance(a, b) {
    if (a.length === 0) return b.length;
    if (b.length === 0) return a.length;

    const matrix = [];

    // increment along the first column of each row
    let i;
    for (i = 0; i <= b.length; i++) {
      matrix[i] = [i];
    }

    // increment each column in the first row
    let j;
    for (j = 0; j <= a.length; j++) {
      matrix[0][j] = j;
    }

    // Fill in the rest of the matrix
    for (i = 1; i <= b.length; i++) {
      for (j = 1; j <= a.length; j++) {
        if (b.charAt(i - 1) == a.charAt(j - 1)) {
          matrix[i][j] = matrix[i - 1][j - 1];
        } else {
          matrix[i][j] = Math.min(
            matrix[i - 1][j - 1] + 1, // substitution
            Math.min(
              matrix[i][j - 1] + 1, // insertion
              matrix[i - 1][j] + 1
            )
          ); // deletion
        }
      }
    }

    return matrix[b.length][a.length];
  }
}

const Activator$1 = Activator;
const ColorPicker$1 = ColorPicker;
const Configurator$1 = Configurator;
const Hammer$1$1 = Hammer$1;
const Popup$1 = Popup;
const VALIDATOR_PRINT_STYLE$1 = VALIDATOR_PRINT_STYLE;
const Validator$1 = Validator;

var util$1 = /*#__PURE__*/Object.freeze({
    __proto__: null,
    Activator: Activator$1,
    Alea: Alea,
    ColorPicker: ColorPicker$1,
    Configurator: Configurator$1,
    DELETE: DELETE,
    HSVToHex: HSVToHex,
    HSVToRGB: HSVToRGB,
    Hammer: Hammer$1$1,
    Popup: Popup$1,
    RGBToHSV: RGBToHSV,
    RGBToHex: RGBToHex,
    VALIDATOR_PRINT_STYLE: VALIDATOR_PRINT_STYLE$1,
    Validator: Validator$1,
    addClassName: addClassName,
    addCssText: addCssText,
    addEventListener: addEventListener,
    binarySearchCustom: binarySearchCustom,
    binarySearchValue: binarySearchValue,
    bridgeObject: bridgeObject,
    copyAndExtendArray: copyAndExtendArray,
    copyArray: copyArray,
    deepExtend: deepExtend,
    deepObjectAssign: deepObjectAssign,
    easingFunctions: easingFunctions,
    equalArray: equalArray,
    extend: extend$1,
    fillIfDefined: fillIfDefined,
    forEach: forEach,
    getAbsoluteLeft: getAbsoluteLeft,
    getAbsoluteRight: getAbsoluteRight,
    getAbsoluteTop: getAbsoluteTop,
    getScrollBarWidth: getScrollBarWidth,
    getTarget: getTarget,
    getType: getType,
    hasParent: hasParent$1,
    hexToHSV: hexToHSV,
    hexToRGB: hexToRGB,
    insertSort: insertSort,
    isDate: isDate,
    isNumber: isNumber,
    isObject: isObject,
    isString: isString,
    isValidHex: isValidHex,
    isValidRGB: isValidRGB,
    isValidRGBA: isValidRGBA,
    mergeOptions: mergeOptions,
    option: option,
    overrideOpacity: overrideOpacity,
    parseColor: parseColor,
    preventDefault: preventDefault,
    pureDeepObjectAssign: pureDeepObjectAssign,
    recursiveDOMDelete: recursiveDOMDelete,
    removeClassName: removeClassName,
    removeCssText: removeCssText,
    removeEventListener: removeEventListener,
    selectiveBridgeObject: selectiveBridgeObject,
    selectiveDeepExtend: selectiveDeepExtend,
    selectiveExtend: selectiveExtend,
    selectiveNotDeepExtend: selectiveNotDeepExtend,
    throttle: throttle,
    toArray: toArray$1,
    topMost: topMost,
    updateProperty: updateProperty
});

var rng_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = rng;

var _crypto = _interopRequireDefault(require$$0__default['default']);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function rng() {
  return _crypto.default.randomBytes(16);
}

module.exports = exports.default;
});

var bytesToUuid_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

/**
 * Convert array of 16 byte values to UUID string format of the form:
 * XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
 */
var byteToHex = [];

for (var i = 0; i < 256; ++i) {
  byteToHex[i] = (i + 0x100).toString(16).substr(1);
}

function bytesToUuid(buf, offset) {
  var i = offset || 0;
  var bth = byteToHex; // join used to fix memory issue caused by concatenation: https://bugs.chromium.org/p/v8/issues/detail?id=3175#c4

  return [bth[buf[i++]], bth[buf[i++]], bth[buf[i++]], bth[buf[i++]], '-', bth[buf[i++]], bth[buf[i++]], '-', bth[buf[i++]], bth[buf[i++]], '-', bth[buf[i++]], bth[buf[i++]], '-', bth[buf[i++]], bth[buf[i++]], bth[buf[i++]], bth[buf[i++]], bth[buf[i++]], bth[buf[i++]]].join('');
}

var _default = bytesToUuid;
exports.default = _default;
module.exports = exports.default;
});

var v1_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _rng = _interopRequireDefault(rng_1);

var _bytesToUuid = _interopRequireDefault(bytesToUuid_1);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

// **`v1()` - Generate time-based UUID**
//
// Inspired by https://github.com/LiosK/UUID.js
// and http://docs.python.org/library/uuid.html
var _nodeId;

var _clockseq; // Previous uuid creation time


var _lastMSecs = 0;
var _lastNSecs = 0; // See https://github.com/uuidjs/uuid for API details

function v1(options, buf, offset) {
  var i = buf && offset || 0;
  var b = buf || [];
  options = options || {};
  var node = options.node || _nodeId;
  var clockseq = options.clockseq !== undefined ? options.clockseq : _clockseq; // node and clockseq need to be initialized to random values if they're not
  // specified.  We do this lazily to minimize issues related to insufficient
  // system entropy.  See #189

  if (node == null || clockseq == null) {
    var seedBytes = options.random || (options.rng || _rng.default)();

    if (node == null) {
      // Per 4.5, create and 48-bit node id, (47 random bits + multicast bit = 1)
      node = _nodeId = [seedBytes[0] | 0x01, seedBytes[1], seedBytes[2], seedBytes[3], seedBytes[4], seedBytes[5]];
    }

    if (clockseq == null) {
      // Per 4.2.2, randomize (14 bit) clockseq
      clockseq = _clockseq = (seedBytes[6] << 8 | seedBytes[7]) & 0x3fff;
    }
  } // UUID timestamps are 100 nano-second units since the Gregorian epoch,
  // (1582-10-15 00:00).  JSNumbers aren't precise enough for this, so
  // time is handled internally as 'msecs' (integer milliseconds) and 'nsecs'
  // (100-nanoseconds offset from msecs) since unix epoch, 1970-01-01 00:00.


  var msecs = options.msecs !== undefined ? options.msecs : new Date().getTime(); // Per 4.2.1.2, use count of uuid's generated during the current clock
  // cycle to simulate higher resolution clock

  var nsecs = options.nsecs !== undefined ? options.nsecs : _lastNSecs + 1; // Time since last uuid creation (in msecs)

  var dt = msecs - _lastMSecs + (nsecs - _lastNSecs) / 10000; // Per 4.2.1.2, Bump clockseq on clock regression

  if (dt < 0 && options.clockseq === undefined) {
    clockseq = clockseq + 1 & 0x3fff;
  } // Reset nsecs if clock regresses (new clockseq) or we've moved onto a new
  // time interval


  if ((dt < 0 || msecs > _lastMSecs) && options.nsecs === undefined) {
    nsecs = 0;
  } // Per 4.2.1.2 Throw error if too many uuids are requested


  if (nsecs >= 10000) {
    throw new Error("uuid.v1(): Can't create more than 10M uuids/sec");
  }

  _lastMSecs = msecs;
  _lastNSecs = nsecs;
  _clockseq = clockseq; // Per 4.1.4 - Convert from unix epoch to Gregorian epoch

  msecs += 12219292800000; // `time_low`

  var tl = ((msecs & 0xfffffff) * 10000 + nsecs) % 0x100000000;
  b[i++] = tl >>> 24 & 0xff;
  b[i++] = tl >>> 16 & 0xff;
  b[i++] = tl >>> 8 & 0xff;
  b[i++] = tl & 0xff; // `time_mid`

  var tmh = msecs / 0x100000000 * 10000 & 0xfffffff;
  b[i++] = tmh >>> 8 & 0xff;
  b[i++] = tmh & 0xff; // `time_high_and_version`

  b[i++] = tmh >>> 24 & 0xf | 0x10; // include version

  b[i++] = tmh >>> 16 & 0xff; // `clock_seq_hi_and_reserved` (Per 4.2.2 - include variant)

  b[i++] = clockseq >>> 8 | 0x80; // `clock_seq_low`

  b[i++] = clockseq & 0xff; // `node`

  for (var n = 0; n < 6; ++n) {
    b[i + n] = node[n];
  }

  return buf ? buf : (0, _bytesToUuid.default)(b);
}

var _default = v1;
exports.default = _default;
module.exports = exports.default;
});

var v35 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = _default;
exports.URL = exports.DNS = void 0;

var _bytesToUuid = _interopRequireDefault(bytesToUuid_1);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function uuidToBytes(uuid) {
  // Note: We assume we're being passed a valid uuid string
  var bytes = [];
  uuid.replace(/[a-fA-F0-9]{2}/g, function (hex) {
    bytes.push(parseInt(hex, 16));
  });
  return bytes;
}

function stringToBytes(str) {
  str = unescape(encodeURIComponent(str)); // UTF8 escape

  var bytes = new Array(str.length);

  for (var i = 0; i < str.length; i++) {
    bytes[i] = str.charCodeAt(i);
  }

  return bytes;
}

const DNS = '6ba7b810-9dad-11d1-80b4-00c04fd430c8';
exports.DNS = DNS;
const URL = '6ba7b811-9dad-11d1-80b4-00c04fd430c8';
exports.URL = URL;

function _default(name, version, hashfunc) {
  var generateUUID = function (value, namespace, buf, offset) {
    var off = buf && offset || 0;
    if (typeof value == 'string') value = stringToBytes(value);
    if (typeof namespace == 'string') namespace = uuidToBytes(namespace);
    if (!Array.isArray(value)) throw TypeError('value must be an array of bytes');
    if (!Array.isArray(namespace) || namespace.length !== 16) throw TypeError('namespace must be uuid string or an Array of 16 byte values'); // Per 4.3

    var bytes = hashfunc(namespace.concat(value));
    bytes[6] = bytes[6] & 0x0f | version;
    bytes[8] = bytes[8] & 0x3f | 0x80;

    if (buf) {
      for (var idx = 0; idx < 16; ++idx) {
        buf[off + idx] = bytes[idx];
      }
    }

    return buf || (0, _bytesToUuid.default)(bytes);
  }; // Function#name is not settable on some platforms (#270)


  try {
    generateUUID.name = name;
  } catch (err) {} // For CommonJS default export support


  generateUUID.DNS = DNS;
  generateUUID.URL = URL;
  return generateUUID;
}
});

var md5_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _crypto = _interopRequireDefault(require$$0__default['default']);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function md5(bytes) {
  if (Array.isArray(bytes)) {
    bytes = Buffer.from(bytes);
  } else if (typeof bytes === 'string') {
    bytes = Buffer.from(bytes, 'utf8');
  }

  return _crypto.default.createHash('md5').update(bytes).digest();
}

var _default = md5;
exports.default = _default;
module.exports = exports.default;
});

var v3_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _v = _interopRequireDefault(v35);

var _md = _interopRequireDefault(md5_1);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const v3 = (0, _v.default)('v3', 0x30, _md.default);
var _default = v3;
exports.default = _default;
module.exports = exports.default;
});

var v4_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _rng = _interopRequireDefault(rng_1);

var _bytesToUuid = _interopRequireDefault(bytesToUuid_1);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function v4(options, buf, offset) {
  var i = buf && offset || 0;

  if (typeof options == 'string') {
    buf = options === 'binary' ? new Array(16) : null;
    options = null;
  }

  options = options || {};

  var rnds = options.random || (options.rng || _rng.default)(); // Per 4.4, set bits for version and `clock_seq_hi_and_reserved`


  rnds[6] = rnds[6] & 0x0f | 0x40;
  rnds[8] = rnds[8] & 0x3f | 0x80; // Copy bytes to buffer, if provided

  if (buf) {
    for (var ii = 0; ii < 16; ++ii) {
      buf[i + ii] = rnds[ii];
    }
  }

  return buf || (0, _bytesToUuid.default)(rnds);
}

var _default = v4;
exports.default = _default;
module.exports = exports.default;
});

var sha1_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _crypto = _interopRequireDefault(require$$0__default['default']);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function sha1(bytes) {
  if (Array.isArray(bytes)) {
    bytes = Buffer.from(bytes);
  } else if (typeof bytes === 'string') {
    bytes = Buffer.from(bytes, 'utf8');
  }

  return _crypto.default.createHash('sha1').update(bytes).digest();
}

var _default = sha1;
exports.default = _default;
module.exports = exports.default;
});

var v5_1 = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _v = _interopRequireDefault(v35);

var _sha = _interopRequireDefault(sha1_1);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const v5 = (0, _v.default)('v5', 0x50, _sha.default);
var _default = v5;
exports.default = _default;
module.exports = exports.default;
});

var dist = createCommonjsModule(function (module, exports) {

Object.defineProperty(exports, "__esModule", {
  value: true
});
Object.defineProperty(exports, "v1", {
  enumerable: true,
  get: function () {
    return _v.default;
  }
});
Object.defineProperty(exports, "v3", {
  enumerable: true,
  get: function () {
    return _v2.default;
  }
});
Object.defineProperty(exports, "v4", {
  enumerable: true,
  get: function () {
    return _v3.default;
  }
});
Object.defineProperty(exports, "v5", {
  enumerable: true,
  get: function () {
    return _v4.default;
  }
});

var _v = _interopRequireDefault(v1_1);

var _v2 = _interopRequireDefault(v3_1);

var _v3 = _interopRequireDefault(v4_1);

var _v4 = _interopRequireDefault(v5_1);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
});

/**
 * vis-data
 * http://visjs.org/
 *
 * Manage unstructured data using DataSet. Add, update, and remove data, and listen for changes in the data.
 *
 * @version 7.1.2
 * @date    2021-01-08T20:37:11.601Z
 *
 * @copyright (c) 2011-2017 Almende B.V, http://almende.com
 * @copyright (c) 2017-2019 visjs contributors, https://github.com/visjs
 *
 * @license
 * vis.js is dual licensed under both
 *
 *   1. The Apache 2.0 License
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *   and
 *
 *   2. The MIT License
 *      http://opensource.org/licenses/MIT
 *
 * vis.js may be distributed under either license.
 */

/**
 * Create new data pipe.
 *
 * @param from - The source data set or data view.
 *
 * @remarks
 * Example usage:
 * ```typescript
 * interface AppItem {
 *   whoami: string;
 *   appData: unknown;
 *   visData: VisItem;
 * }
 * interface VisItem {
 *   id: number;
 *   label: string;
 *   color: string;
 *   x: number;
 *   y: number;
 * }
 *
 * const ds1 = new DataSet<AppItem, "whoami">([], { fieldId: "whoami" });
 * const ds2 = new DataSet<VisItem, "id">();
 *
 * const pipe = createNewDataPipeFrom(ds1)
 *   .filter((item): boolean => item.enabled === true)
 *   .map<VisItem, "id">((item): VisItem => item.visData)
 *   .to(ds2);
 *
 * pipe.start();
 * ```
 *
 * @returns A factory whose methods can be used to configure the pipe.
 */
function createNewDataPipeFrom(from) {
    return new DataPipeUnderConstruction(from);
}
/**
 * Internal implementation of the pipe. This should be accessible only through
 * `createNewDataPipeFrom` from the outside.
 *
 * @typeParam SI - Source item type.
 * @typeParam SP - Source item type's id property name.
 * @typeParam TI - Target item type.
 * @typeParam TP - Target item type's id property name.
 */
class SimpleDataPipe {
    /**
     * Create a new data pipe.
     *
     * @param _source - The data set or data view that will be observed.
     * @param _transformers - An array of transforming functions to be used to
     * filter or transform the items in the pipe.
     * @param _target - The data set or data view that will receive the items.
     */
    constructor(_source, _transformers, _target) {
        this._source = _source;
        this._transformers = _transformers;
        this._target = _target;
        /**
         * Bound listeners for use with `DataInterface['on' | 'off']`.
         */
        this._listeners = {
            add: this._add.bind(this),
            remove: this._remove.bind(this),
            update: this._update.bind(this),
        };
    }
    /** @inheritDoc */
    all() {
        this._target.update(this._transformItems(this._source.get()));
        return this;
    }
    /** @inheritDoc */
    start() {
        this._source.on("add", this._listeners.add);
        this._source.on("remove", this._listeners.remove);
        this._source.on("update", this._listeners.update);
        return this;
    }
    /** @inheritDoc */
    stop() {
        this._source.off("add", this._listeners.add);
        this._source.off("remove", this._listeners.remove);
        this._source.off("update", this._listeners.update);
        return this;
    }
    /**
     * Apply the transformers to the items.
     *
     * @param items - The items to be transformed.
     *
     * @returns The transformed items.
     */
    _transformItems(items) {
        return this._transformers.reduce((items, transform) => {
            return transform(items);
        }, items);
    }
    /**
     * Handle an add event.
     *
     * @param _name - Ignored.
     * @param payload - The payload containing the ids of the added items.
     */
    _add(_name, payload) {
        if (payload == null) {
            return;
        }
        this._target.add(this._transformItems(this._source.get(payload.items)));
    }
    /**
     * Handle an update event.
     *
     * @param _name - Ignored.
     * @param payload - The payload containing the ids of the updated items.
     */
    _update(_name, payload) {
        if (payload == null) {
            return;
        }
        this._target.update(this._transformItems(this._source.get(payload.items)));
    }
    /**
     * Handle a remove event.
     *
     * @param _name - Ignored.
     * @param payload - The payload containing the data of the removed items.
     */
    _remove(_name, payload) {
        if (payload == null) {
            return;
        }
        this._target.remove(this._transformItems(payload.oldData));
    }
}
/**
 * Internal implementation of the pipe factory. This should be accessible
 * only through `createNewDataPipeFrom` from the outside.
 *
 * @typeParam TI - Target item type.
 * @typeParam TP - Target item type's id property name.
 */
class DataPipeUnderConstruction {
    /**
     * Create a new data pipe factory. This is an internal constructor that
     * should never be called from outside of this file.
     *
     * @param _source - The source data set or data view for this pipe.
     */
    constructor(_source) {
        this._source = _source;
        /**
         * Array transformers used to transform items within the pipe. This is typed
         * as any for the sake of simplicity.
         */
        this._transformers = [];
    }
    /**
     * Filter the items.
     *
     * @param callback - A filtering function that returns true if given item
     * should be piped and false if not.
     *
     * @returns This factory for further configuration.
     */
    filter(callback) {
        this._transformers.push((input) => input.filter(callback));
        return this;
    }
    /**
     * Map each source item to a new type.
     *
     * @param callback - A mapping function that takes a source item and returns
     * corresponding mapped item.
     *
     * @typeParam TI - Target item type.
     * @typeParam TP - Target item type's id property name.
     *
     * @returns This factory for further configuration.
     */
    map(callback) {
        this._transformers.push((input) => input.map(callback));
        return this;
    }
    /**
     * Map each source item to zero or more items of a new type.
     *
     * @param callback - A mapping function that takes a source item and returns
     * an array of corresponding mapped items.
     *
     * @typeParam TI - Target item type.
     * @typeParam TP - Target item type's id property name.
     *
     * @returns This factory for further configuration.
     */
    flatMap(callback) {
        this._transformers.push((input) => input.flatMap(callback));
        return this;
    }
    /**
     * Connect this pipe to given data set.
     *
     * @param target - The data set that will receive the items from this pipe.
     *
     * @returns The pipe connected between given data sets and performing
     * configured transformation on the processed items.
     */
    to(target) {
        return new SimpleDataPipe(this._source, this._transformers, target);
    }
}

/**
 * Determine whether a value can be used as an id.
 *
 * @param value - Input value of unknown type.
 *
 * @returns True if the value is valid id, false otherwise.
 */
function isId(value) {
    return typeof value === "string" || typeof value === "number";
}

/**
 * A queue.
 *
 * @typeParam T - The type of method names to be replaced by queued versions.
 */
class Queue {
    /**
     * Construct a new Queue.
     *
     * @param options - Queue configuration.
     */
    constructor(options) {
        this._queue = [];
        this._timeout = null;
        this._extended = null;
        // options
        this.delay = null;
        this.max = Infinity;
        this.setOptions(options);
    }
    /**
     * Update the configuration of the queue.
     *
     * @param options - Queue configuration.
     */
    setOptions(options) {
        if (options && typeof options.delay !== "undefined") {
            this.delay = options.delay;
        }
        if (options && typeof options.max !== "undefined") {
            this.max = options.max;
        }
        this._flushIfNeeded();
    }
    /**
     * Extend an object with queuing functionality.
     * The object will be extended with a function flush, and the methods provided in options.replace will be replaced with queued ones.
     *
     * @param object - The object to be extended.
     * @param options - Additional options.
     *
     * @returns The created queue.
     */
    static extend(object, options) {
        const queue = new Queue(options);
        if (object.flush !== undefined) {
            throw new Error("Target object already has a property flush");
        }
        object.flush = () => {
            queue.flush();
        };
        const methods = [
            {
                name: "flush",
                original: undefined,
            },
        ];
        if (options && options.replace) {
            for (let i = 0; i < options.replace.length; i++) {
                const name = options.replace[i];
                methods.push({
                    name: name,
                    // @TODO: better solution?
                    original: object[name],
                });
                // @TODO: better solution?
                queue.replace(object, name);
            }
        }
        queue._extended = {
            object: object,
            methods: methods,
        };
        return queue;
    }
    /**
     * Destroy the queue. The queue will first flush all queued actions, and in case it has extended an object, will restore the original object.
     */
    destroy() {
        this.flush();
        if (this._extended) {
            const object = this._extended.object;
            const methods = this._extended.methods;
            for (let i = 0; i < methods.length; i++) {
                const method = methods[i];
                if (method.original) {
                    // @TODO: better solution?
                    object[method.name] = method.original;
                }
                else {
                    // @TODO: better solution?
                    delete object[method.name];
                }
            }
            this._extended = null;
        }
    }
    /**
     * Replace a method on an object with a queued version.
     *
     * @param object - Object having the method.
     * @param method - The method name.
     */
    replace(object, method) {
        /* eslint-disable-next-line @typescript-eslint/no-this-alias -- Function this is necessary in the function bellow, so class this has to be saved into a variable here. */
        const me = this;
        const original = object[method];
        if (!original) {
            throw new Error("Method " + method + " undefined");
        }
        object[method] = function (...args) {
            // add this call to the queue
            me.queue({
                args: args,
                fn: original,
                context: this,
            });
        };
    }
    /**
     * Queue a call.
     *
     * @param entry - The function or entry to be queued.
     */
    queue(entry) {
        if (typeof entry === "function") {
            this._queue.push({ fn: entry });
        }
        else {
            this._queue.push(entry);
        }
        this._flushIfNeeded();
    }
    /**
     * Check whether the queue needs to be flushed.
     */
    _flushIfNeeded() {
        // flush when the maximum is exceeded.
        if (this._queue.length > this.max) {
            this.flush();
        }
        // flush after a period of inactivity when a delay is configured
        if (this._timeout != null) {
            clearTimeout(this._timeout);
            this._timeout = null;
        }
        if (this.queue.length > 0 && typeof this.delay === "number") {
            this._timeout = setTimeout(() => {
                this.flush();
            }, this.delay);
        }
    }
    /**
     * Flush all queued calls
     */
    flush() {
        this._queue.splice(0).forEach((entry) => {
            entry.fn.apply(entry.context || entry.fn, entry.args || []);
        });
    }
}

/**
 * [[DataSet]] code that can be reused in [[DataView]] or other similar implementations of [[DataInterface]].
 *
 * @typeParam Item - Item type that may or may not have an id.
 * @typeParam IdProp - Name of the property that contains the id.
 */
class DataSetPart {
    constructor() {
        this._subscribers = {
            "*": [],
            add: [],
            remove: [],
            update: [],
        };
        /**
         * @deprecated Use on instead (PS: DataView.subscribe === DataView.on).
         */
        this.subscribe = DataSetPart.prototype.on;
        /**
         * @deprecated Use off instead (PS: DataView.unsubscribe === DataView.off).
         */
        this.unsubscribe = DataSetPart.prototype.off;
    }
    /**
     * Trigger an event
     *
     * @param event - Event name.
     * @param payload - Event payload.
     * @param senderId - Id of the sender.
     */
    _trigger(event, payload, senderId) {
        if (event === "*") {
            throw new Error("Cannot trigger event *");
        }
        [...this._subscribers[event], ...this._subscribers["*"]].forEach((subscriber) => {
            subscriber(event, payload, senderId != null ? senderId : null);
        });
    }
    /**
     * Subscribe to an event, add an event listener.
     *
     * @remarks Non-function callbacks are ignored.
     *
     * @param event - Event name.
     * @param callback - Callback method.
     */
    on(event, callback) {
        if (typeof callback === "function") {
            this._subscribers[event].push(callback);
        }
        // @TODO: Maybe throw for invalid callbacks?
    }
    /**
     * Unsubscribe from an event, remove an event listener.
     *
     * @remarks If the same callback was subscribed more than once **all** occurences will be removed.
     *
     * @param event - Event name.
     * @param callback - Callback method.
     */
    off(event, callback) {
        this._subscribers[event] = this._subscribers[event].filter((subscriber) => subscriber !== callback);
    }
}

/**
 * Data stream
 *
 * @remarks
 * [[DataStream]] offers an always up to date stream of items from a [[DataSet]] or [[DataView]].
 * That means that the stream is evaluated at the time of iteration, conversion to another data type or when [[cache]] is called, not when the [[DataStream]] was created.
 * Multiple invocations of for example [[toItemArray]] may yield different results (if the data source like for example [[DataSet]] gets modified).
 *
 * @typeParam Item - The item type this stream is going to work with.
 */
class DataStream {
    /**
     * Create a new data stream.
     *
     * @param pairs - The id, item pairs.
     */
    constructor(pairs) {
        this._pairs = pairs;
    }
    /**
     * Return an iterable of key, value pairs for every entry in the stream.
     */
    *[Symbol.iterator]() {
        for (const [id, item] of this._pairs) {
            yield [id, item];
        }
    }
    /**
     * Return an iterable of key, value pairs for every entry in the stream.
     */
    *entries() {
        for (const [id, item] of this._pairs) {
            yield [id, item];
        }
    }
    /**
     * Return an iterable of keys in the stream.
     */
    *keys() {
        for (const [id] of this._pairs) {
            yield id;
        }
    }
    /**
     * Return an iterable of values in the stream.
     */
    *values() {
        for (const [, item] of this._pairs) {
            yield item;
        }
    }
    /**
     * Return an array containing all the ids in this stream.
     *
     * @remarks
     * The array may contain duplicities.
     *
     * @returns The array with all ids from this stream.
     */
    toIdArray() {
        return [...this._pairs].map((pair) => pair[0]);
    }
    /**
     * Return an array containing all the items in this stream.
     *
     * @remarks
     * The array may contain duplicities.
     *
     * @returns The array with all items from this stream.
     */
    toItemArray() {
        return [...this._pairs].map((pair) => pair[1]);
    }
    /**
     * Return an array containing all the entries in this stream.
     *
     * @remarks
     * The array may contain duplicities.
     *
     * @returns The array with all entries from this stream.
     */
    toEntryArray() {
        return [...this._pairs];
    }
    /**
     * Return an object map containing all the items in this stream accessible by ids.
     *
     * @remarks
     * In case of duplicate ids (coerced to string so `7 == '7'`) the last encoutered appears in the returned object.
     *
     * @returns The object map of all id → item pairs from this stream.
     */
    toObjectMap() {
        const map = Object.create(null);
        for (const [id, item] of this._pairs) {
            map[id] = item;
        }
        return map;
    }
    /**
     * Return a map containing all the items in this stream accessible by ids.
     *
     * @returns The map of all id → item pairs from this stream.
     */
    toMap() {
        return new Map(this._pairs);
    }
    /**
     * Return a set containing all the (unique) ids in this stream.
     *
     * @returns The set of all ids from this stream.
     */
    toIdSet() {
        return new Set(this.toIdArray());
    }
    /**
     * Return a set containing all the (unique) items in this stream.
     *
     * @returns The set of all items from this stream.
     */
    toItemSet() {
        return new Set(this.toItemArray());
    }
    /**
     * Cache the items from this stream.
     *
     * @remarks
     * This method allows for items to be fetched immediatelly and used (possibly multiple times) later.
     * It can also be used to optimize performance as [[DataStream]] would otherwise reevaluate everything upon each iteration.
     *
     * ## Example
     * ```javascript
     * const ds = new DataSet([…])
     *
     * const cachedStream = ds.stream()
     *   .filter(…)
     *   .sort(…)
     *   .map(…)
     *   .cached(…) // Data are fetched, processed and cached here.
     *
     * ds.clear()
     * chachedStream // Still has all the items.
     * ```
     *
     * @returns A new [[DataStream]] with cached items (detached from the original [[DataSet]]).
     */
    cache() {
        return new DataStream([...this._pairs]);
    }
    /**
     * Get the distinct values of given property.
     *
     * @param callback - The function that picks and possibly converts the property.
     *
     * @typeParam T - The type of the distinct value.
     *
     * @returns A set of all distinct properties.
     */
    distinct(callback) {
        const set = new Set();
        for (const [id, item] of this._pairs) {
            set.add(callback(item, id));
        }
        return set;
    }
    /**
     * Filter the items of the stream.
     *
     * @param callback - The function that decides whether an item will be included.
     *
     * @returns A new data stream with the filtered items.
     */
    filter(callback) {
        const pairs = this._pairs;
        return new DataStream({
            *[Symbol.iterator]() {
                for (const [id, item] of pairs) {
                    if (callback(item, id)) {
                        yield [id, item];
                    }
                }
            },
        });
    }
    /**
     * Execute a callback for each item of the stream.
     *
     * @param callback - The function that will be invoked for each item.
     */
    forEach(callback) {
        for (const [id, item] of this._pairs) {
            callback(item, id);
        }
    }
    /**
     * Map the items into a different type.
     *
     * @param callback - The function that does the conversion.
     *
     * @typeParam Mapped - The type of the item after mapping.
     *
     * @returns A new data stream with the mapped items.
     */
    map(callback) {
        const pairs = this._pairs;
        return new DataStream({
            *[Symbol.iterator]() {
                for (const [id, item] of pairs) {
                    yield [id, callback(item, id)];
                }
            },
        });
    }
    /**
     * Get the item with the maximum value of given property.
     *
     * @param callback - The function that picks and possibly converts the property.
     *
     * @returns The item with the maximum if found otherwise null.
     */
    max(callback) {
        const iter = this._pairs[Symbol.iterator]();
        let curr = iter.next();
        if (curr.done) {
            return null;
        }
        let maxItem = curr.value[1];
        let maxValue = callback(curr.value[1], curr.value[0]);
        while (!(curr = iter.next()).done) {
            const [id, item] = curr.value;
            const value = callback(item, id);
            if (value > maxValue) {
                maxValue = value;
                maxItem = item;
            }
        }
        return maxItem;
    }
    /**
     * Get the item with the minimum value of given property.
     *
     * @param callback - The function that picks and possibly converts the property.
     *
     * @returns The item with the minimum if found otherwise null.
     */
    min(callback) {
        const iter = this._pairs[Symbol.iterator]();
        let curr = iter.next();
        if (curr.done) {
            return null;
        }
        let minItem = curr.value[1];
        let minValue = callback(curr.value[1], curr.value[0]);
        while (!(curr = iter.next()).done) {
            const [id, item] = curr.value;
            const value = callback(item, id);
            if (value < minValue) {
                minValue = value;
                minItem = item;
            }
        }
        return minItem;
    }
    /**
     * Reduce the items into a single value.
     *
     * @param callback - The function that does the reduction.
     * @param accumulator - The initial value of the accumulator.
     *
     * @typeParam T - The type of the accumulated value.
     *
     * @returns The reduced value.
     */
    reduce(callback, accumulator) {
        for (const [id, item] of this._pairs) {
            accumulator = callback(accumulator, item, id);
        }
        return accumulator;
    }
    /**
     * Sort the items.
     *
     * @param callback - Item comparator.
     *
     * @returns A new stream with sorted items.
     */
    sort(callback) {
        return new DataStream({
            [Symbol.iterator]: () => [...this._pairs]
                .sort(([idA, itemA], [idB, itemB]) => callback(itemA, itemB, idA, idB))[Symbol.iterator](),
        });
    }
}

/**
 * Add an id to given item if it doesn't have one already.
 *
 * @remarks
 * The item will be modified.
 *
 * @param item - The item that will have an id after a call to this function.
 * @param idProp - The key of the id property.
 *
 * @typeParam Item - Item type that may or may not have an id.
 * @typeParam IdProp - Name of the property that contains the id.
 *
 * @returns true
 */
function ensureFullItem(item, idProp) {
    if (item[idProp] == null) {
        // generate an id
        item[idProp] = dist.v4();
    }
    return item;
}
/**
 * # DataSet
 *
 * Vis.js comes with a flexible DataSet, which can be used to hold and
 * manipulate unstructured data and listen for changes in the data. The DataSet
 * is key/value based. Data items can be added, updated and removed from the
 * DataSet, and one can subscribe to changes in the DataSet. The data in the
 * DataSet can be filtered and ordered. Data can be normalized when appending it
 * to the DataSet as well.
 *
 * ## Example
 *
 * The following example shows how to use a DataSet.
 *
 * ```javascript
 * // create a DataSet
 * var options = {};
 * var data = new vis.DataSet(options);
 *
 * // add items
 * // note that the data items can contain different properties and data formats
 * data.add([
 *   {id: 1, text: 'item 1', date: new Date(2013, 6, 20), group: 1, first: true},
 *   {id: 2, text: 'item 2', date: '2013-06-23', group: 2},
 *   {id: 3, text: 'item 3', date: '2013-06-25', group: 2},
 *   {id: 4, text: 'item 4'}
 * ]);
 *
 * // subscribe to any change in the DataSet
 * data.on('*', function (event, properties, senderId) {
 *   console.log('event', event, properties);
 * });
 *
 * // update an existing item
 * data.update({id: 2, group: 1});
 *
 * // remove an item
 * data.remove(4);
 *
 * // get all ids
 * var ids = data.getIds();
 * console.log('ids', ids);
 *
 * // get a specific item
 * var item1 = data.get(1);
 * console.log('item1', item1);
 *
 * // retrieve a filtered subset of the data
 * var items = data.get({
 *   filter: function (item) {
 *     return item.group == 1;
 *   }
 * });
 * console.log('filtered items', items);
 * ```
 *
 * @typeParam Item - Item type that may or may not have an id.
 * @typeParam IdProp - Name of the property that contains the id.
 */
class DataSet extends DataSetPart {
    /**
     * Construct a new DataSet.
     *
     * @param data - Initial data or options.
     * @param options - Options (type error if data is also options).
     */
    constructor(data, options) {
        super();
        this._queue = null;
        // correctly read optional arguments
        if (data && !Array.isArray(data)) {
            options = data;
            data = [];
        }
        this._options = options || {};
        this._data = new Map(); // map with data indexed by id
        this.length = 0; // number of items in the DataSet
        this._idProp = this._options.fieldId || "id"; // name of the field containing id
        // add initial data when provided
        if (data && data.length) {
            this.add(data);
        }
        this.setOptions(options);
    }
    /** @inheritDoc */
    get idProp() {
        return this._idProp;
    }
    /**
     * Set new options.
     *
     * @param options - The new options.
     */
    setOptions(options) {
        if (options && options.queue !== undefined) {
            if (options.queue === false) {
                // delete queue if loaded
                if (this._queue) {
                    this._queue.destroy();
                    this._queue = null;
                }
            }
            else {
                // create queue and update its options
                if (!this._queue) {
                    this._queue = Queue.extend(this, {
                        replace: ["add", "update", "remove"],
                    });
                }
                if (options.queue && typeof options.queue === "object") {
                    this._queue.setOptions(options.queue);
                }
            }
        }
    }
    /**
     * Add a data item or an array with items.
     *
     * After the items are added to the DataSet, the DataSet will trigger an event `add`. When a `senderId` is provided, this id will be passed with the triggered event to all subscribers.
     *
     * ## Example
     *
     * ```javascript
     * // create a DataSet
     * const data = new vis.DataSet()
     *
     * // add items
     * const ids = data.add([
     *   { id: 1, text: 'item 1' },
     *   { id: 2, text: 'item 2' },
     *   { text: 'item without an id' }
     * ])
     *
     * console.log(ids) // [1, 2, '<UUIDv4>']
     * ```
     *
     * @param data - Items to be added (ids will be generated if missing).
     * @param senderId - Sender id.
     *
     * @returns addedIds - Array with the ids (generated if not present) of the added items.
     *
     * @throws When an item with the same id as any of the added items already exists.
     */
    add(data, senderId) {
        const addedIds = [];
        let id;
        if (Array.isArray(data)) {
            // Array
            const idsToAdd = data.map((d) => d[this._idProp]);
            if (idsToAdd.some((id) => this._data.has(id))) {
                throw new Error("A duplicate id was found in the parameter array.");
            }
            for (let i = 0, len = data.length; i < len; i++) {
                id = this._addItem(data[i]);
                addedIds.push(id);
            }
        }
        else if (data && typeof data === "object") {
            // Single item
            id = this._addItem(data);
            addedIds.push(id);
        }
        else {
            throw new Error("Unknown dataType");
        }
        if (addedIds.length) {
            this._trigger("add", { items: addedIds }, senderId);
        }
        return addedIds;
    }
    /**
     * Update existing items. When an item does not exist, it will be created.
     *
     * @remarks
     * The provided properties will be merged in the existing item. When an item does not exist, it will be created.
     *
     * After the items are updated, the DataSet will trigger an event `add` for the added items, and an event `update`. When a `senderId` is provided, this id will be passed with the triggered event to all subscribers.
     *
     * ## Example
     *
     * ```javascript
     * // create a DataSet
     * const data = new vis.DataSet([
     *   { id: 1, text: 'item 1' },
     *   { id: 2, text: 'item 2' },
     *   { id: 3, text: 'item 3' }
     * ])
     *
     * // update items
     * const ids = data.update([
     *   { id: 2, text: 'item 2 (updated)' },
     *   { id: 4, text: 'item 4 (new)' }
     * ])
     *
     * console.log(ids) // [2, 4]
     * ```
     *
     * ## Warning for TypeScript users
     * This method may introduce partial items into the data set. Use add or updateOnly instead for better type safety.
     *
     * @param data - Items to be updated (if the id is already present) or added (if the id is missing).
     * @param senderId - Sender id.
     *
     * @returns updatedIds - The ids of the added (these may be newly generated if there was no id in the item from the data) or updated items.
     *
     * @throws When the supplied data is neither an item nor an array of items.
     */
    update(data, senderId) {
        const addedIds = [];
        const updatedIds = [];
        const oldData = [];
        const updatedData = [];
        const idProp = this._idProp;
        const addOrUpdate = (item) => {
            const origId = item[idProp];
            if (origId != null && this._data.has(origId)) {
                const fullItem = item; // it has an id, therefore it is a fullitem
                const oldItem = Object.assign({}, this._data.get(origId));
                // update item
                const id = this._updateItem(fullItem);
                updatedIds.push(id);
                updatedData.push(fullItem);
                oldData.push(oldItem);
            }
            else {
                // add new item
                const id = this._addItem(item);
                addedIds.push(id);
            }
        };
        if (Array.isArray(data)) {
            // Array
            for (let i = 0, len = data.length; i < len; i++) {
                if (data[i] && typeof data[i] === "object") {
                    addOrUpdate(data[i]);
                }
                else {
                    console.warn("Ignoring input item, which is not an object at index " + i);
                }
            }
        }
        else if (data && typeof data === "object") {
            // Single item
            addOrUpdate(data);
        }
        else {
            throw new Error("Unknown dataType");
        }
        if (addedIds.length) {
            this._trigger("add", { items: addedIds }, senderId);
        }
        if (updatedIds.length) {
            const props = { items: updatedIds, oldData: oldData, data: updatedData };
            // TODO: remove deprecated property 'data' some day
            //Object.defineProperty(props, 'data', {
            //  'get': (function() {
            //    console.warn('Property data is deprecated. Use DataSet.get(ids) to retrieve the new data, use the oldData property on this object to get the old data');
            //    return updatedData;
            //  }).bind(this)
            //});
            this._trigger("update", props, senderId);
        }
        return addedIds.concat(updatedIds);
    }
    /**
     * Update existing items. When an item does not exist, an error will be thrown.
     *
     * @remarks
     * The provided properties will be deeply merged into the existing item.
     * When an item does not exist (id not present in the data set or absent), an error will be thrown and nothing will be changed.
     *
     * After the items are updated, the DataSet will trigger an event `update`.
     * When a `senderId` is provided, this id will be passed with the triggered event to all subscribers.
     *
     * ## Example
     *
     * ```javascript
     * // create a DataSet
     * const data = new vis.DataSet([
     *   { id: 1, text: 'item 1' },
     *   { id: 2, text: 'item 2' },
     *   { id: 3, text: 'item 3' },
     * ])
     *
     * // update items
     * const ids = data.update([
     *   { id: 2, text: 'item 2 (updated)' }, // works
     *   // { id: 4, text: 'item 4 (new)' }, // would throw
     *   // { text: 'item 4 (new)' }, // would also throw
     * ])
     *
     * console.log(ids) // [2]
     * ```
     *
     * @param data - Updates (the id and optionally other props) to the items in this data set.
     * @param senderId - Sender id.
     *
     * @returns updatedIds - The ids of the updated items.
     *
     * @throws When the supplied data is neither an item nor an array of items, when the ids are missing.
     */
    updateOnly(data, senderId) {
        if (!Array.isArray(data)) {
            data = [data];
        }
        const updateEventData = data
            .map((update) => {
            const oldData = this._data.get(update[this._idProp]);
            if (oldData == null) {
                throw new Error("Updating non-existent items is not allowed.");
            }
            return { oldData, update };
        })
            .map(({ oldData, update }) => {
            const id = oldData[this._idProp];
            const updatedData = pureDeepObjectAssign(oldData, update);
            this._data.set(id, updatedData);
            return {
                id,
                oldData: oldData,
                updatedData,
            };
        });
        if (updateEventData.length) {
            const props = {
                items: updateEventData.map((value) => value.id),
                oldData: updateEventData.map((value) => value.oldData),
                data: updateEventData.map((value) => value.updatedData),
            };
            // TODO: remove deprecated property 'data' some day
            //Object.defineProperty(props, 'data', {
            //  'get': (function() {
            //    console.warn('Property data is deprecated. Use DataSet.get(ids) to retrieve the new data, use the oldData property on this object to get the old data');
            //    return updatedData;
            //  }).bind(this)
            //});
            this._trigger("update", props, senderId);
            return props.items;
        }
        else {
            return [];
        }
    }
    /** @inheritDoc */
    get(first, second) {
        // @TODO: Woudn't it be better to split this into multiple methods?
        // parse the arguments
        let id = undefined;
        let ids = undefined;
        let options = undefined;
        if (isId(first)) {
            // get(id [, options])
            id = first;
            options = second;
        }
        else if (Array.isArray(first)) {
            // get(ids [, options])
            ids = first;
            options = second;
        }
        else {
            // get([, options])
            options = first;
        }
        // determine the return type
        const returnType = options && options.returnType === "Object" ? "Object" : "Array";
        // @TODO: WTF is this? Or am I missing something?
        // var returnType
        // if (options && options.returnType) {
        //   var allowedValues = ['Array', 'Object']
        //   returnType =
        //     allowedValues.indexOf(options.returnType) == -1
        //       ? 'Array'
        //       : options.returnType
        // } else {
        //   returnType = 'Array'
        // }
        // build options
        const filter = options && options.filter;
        const items = [];
        let item = undefined;
        let itemIds = undefined;
        let itemId = undefined;
        // convert items
        if (id != null) {
            // return a single item
            item = this._data.get(id);
            if (item && filter && !filter(item)) {
                item = undefined;
            }
        }
        else if (ids != null) {
            // return a subset of items
            for (let i = 0, len = ids.length; i < len; i++) {
                item = this._data.get(ids[i]);
                if (item != null && (!filter || filter(item))) {
                    items.push(item);
                }
            }
        }
        else {
            // return all items
            itemIds = [...this._data.keys()];
            for (let i = 0, len = itemIds.length; i < len; i++) {
                itemId = itemIds[i];
                item = this._data.get(itemId);
                if (item != null && (!filter || filter(item))) {
                    items.push(item);
                }
            }
        }
        // order the results
        if (options && options.order && id == undefined) {
            this._sort(items, options.order);
        }
        // filter fields of the items
        if (options && options.fields) {
            const fields = options.fields;
            if (id != undefined && item != null) {
                item = this._filterFields(item, fields);
            }
            else {
                for (let i = 0, len = items.length; i < len; i++) {
                    items[i] = this._filterFields(items[i], fields);
                }
            }
        }
        // return the results
        if (returnType == "Object") {
            const result = {};
            for (let i = 0, len = items.length; i < len; i++) {
                const resultant = items[i];
                // @TODO: Shoudn't this be this._fieldId?
                // result[resultant.id] = resultant
                const id = resultant[this._idProp];
                result[id] = resultant;
            }
            return result;
        }
        else {
            if (id != null) {
                // a single item
                return item ?? null;
            }
            else {
                // just return our array
                return items;
            }
        }
    }
    /** @inheritDoc */
    getIds(options) {
        const data = this._data;
        const filter = options && options.filter;
        const order = options && options.order;
        const itemIds = [...data.keys()];
        const ids = [];
        if (filter) {
            // get filtered items
            if (order) {
                // create ordered list
                const items = [];
                for (let i = 0, len = itemIds.length; i < len; i++) {
                    const id = itemIds[i];
                    const item = this._data.get(id);
                    if (item != null && filter(item)) {
                        items.push(item);
                    }
                }
                this._sort(items, order);
                for (let i = 0, len = items.length; i < len; i++) {
                    ids.push(items[i][this._idProp]);
                }
            }
            else {
                // create unordered list
                for (let i = 0, len = itemIds.length; i < len; i++) {
                    const id = itemIds[i];
                    const item = this._data.get(id);
                    if (item != null && filter(item)) {
                        ids.push(item[this._idProp]);
                    }
                }
            }
        }
        else {
            // get all items
            if (order) {
                // create an ordered list
                const items = [];
                for (let i = 0, len = itemIds.length; i < len; i++) {
                    const id = itemIds[i];
                    items.push(data.get(id));
                }
                this._sort(items, order);
                for (let i = 0, len = items.length; i < len; i++) {
                    ids.push(items[i][this._idProp]);
                }
            }
            else {
                // create unordered list
                for (let i = 0, len = itemIds.length; i < len; i++) {
                    const id = itemIds[i];
                    const item = data.get(id);
                    if (item != null) {
                        ids.push(item[this._idProp]);
                    }
                }
            }
        }
        return ids;
    }
    /** @inheritDoc */
    getDataSet() {
        return this;
    }
    /** @inheritDoc */
    forEach(callback, options) {
        const filter = options && options.filter;
        const data = this._data;
        const itemIds = [...data.keys()];
        if (options && options.order) {
            // execute forEach on ordered list
            const items = this.get(options);
            for (let i = 0, len = items.length; i < len; i++) {
                const item = items[i];
                const id = item[this._idProp];
                callback(item, id);
            }
        }
        else {
            // unordered
            for (let i = 0, len = itemIds.length; i < len; i++) {
                const id = itemIds[i];
                const item = this._data.get(id);
                if (item != null && (!filter || filter(item))) {
                    callback(item, id);
                }
            }
        }
    }
    /** @inheritDoc */
    map(callback, options) {
        const filter = options && options.filter;
        const mappedItems = [];
        const data = this._data;
        const itemIds = [...data.keys()];
        // convert and filter items
        for (let i = 0, len = itemIds.length; i < len; i++) {
            const id = itemIds[i];
            const item = this._data.get(id);
            if (item != null && (!filter || filter(item))) {
                mappedItems.push(callback(item, id));
            }
        }
        // order items
        if (options && options.order) {
            this._sort(mappedItems, options.order);
        }
        return mappedItems;
    }
    /**
     * Filter the fields of an item.
     *
     * @param item - The item whose fields should be filtered.
     * @param fields - The names of the fields that will be kept.
     *
     * @typeParam K - Field name type.
     *
     * @returns The item without any additional fields.
     */
    _filterFields(item, fields) {
        if (!item) {
            // item is null
            return item;
        }
        return (Array.isArray(fields)
            ? // Use the supplied array
                fields
            : // Use the keys of the supplied object
                Object.keys(fields)).reduce((filteredItem, field) => {
            filteredItem[field] = item[field];
            return filteredItem;
        }, {});
    }
    /**
     * Sort the provided array with items.
     *
     * @param items - Items to be sorted in place.
     * @param order - A field name or custom sort function.
     *
     * @typeParam T - The type of the items in the items array.
     */
    _sort(items, order) {
        if (typeof order === "string") {
            // order by provided field name
            const name = order; // field name
            items.sort((a, b) => {
                // @TODO: How to treat missing properties?
                const av = a[name];
                const bv = b[name];
                return av > bv ? 1 : av < bv ? -1 : 0;
            });
        }
        else if (typeof order === "function") {
            // order by sort function
            items.sort(order);
        }
        else {
            // TODO: extend order by an Object {field:string, direction:string}
            //       where direction can be 'asc' or 'desc'
            throw new TypeError("Order must be a function or a string");
        }
    }
    /**
     * Remove an item or multiple items by “reference” (only the id is used) or by id.
     *
     * The method ignores removal of non-existing items, and returns an array containing the ids of the items which are actually removed from the DataSet.
     *
     * After the items are removed, the DataSet will trigger an event `remove` for the removed items. When a `senderId` is provided, this id will be passed with the triggered event to all subscribers.
     *
     * ## Example
     * ```javascript
     * // create a DataSet
     * const data = new vis.DataSet([
     *   { id: 1, text: 'item 1' },
     *   { id: 2, text: 'item 2' },
     *   { id: 3, text: 'item 3' }
     * ])
     *
     * // remove items
     * const ids = data.remove([2, { id: 3 }, 4])
     *
     * console.log(ids) // [2, 3]
     * ```
     *
     * @param id - One or more items or ids of items to be removed.
     * @param senderId - Sender id.
     *
     * @returns The ids of the removed items.
     */
    remove(id, senderId) {
        const removedIds = [];
        const removedItems = [];
        // force everything to be an array for simplicity
        const ids = Array.isArray(id) ? id : [id];
        for (let i = 0, len = ids.length; i < len; i++) {
            const item = this._remove(ids[i]);
            if (item) {
                const itemId = item[this._idProp];
                if (itemId != null) {
                    removedIds.push(itemId);
                    removedItems.push(item);
                }
            }
        }
        if (removedIds.length) {
            this._trigger("remove", { items: removedIds, oldData: removedItems }, senderId);
        }
        return removedIds;
    }
    /**
     * Remove an item by its id or reference.
     *
     * @param id - Id of an item or the item itself.
     *
     * @returns The removed item if removed, null otherwise.
     */
    _remove(id) {
        // @TODO: It origianlly returned the item although the docs say id.
        // The code expects the item, so probably an error in the docs.
        let ident;
        // confirm the id to use based on the args type
        if (isId(id)) {
            ident = id;
        }
        else if (id && typeof id === "object") {
            ident = id[this._idProp]; // look for the identifier field using ._idProp
        }
        // do the removing if the item is found
        if (ident != null && this._data.has(ident)) {
            const item = this._data.get(ident) || null;
            this._data.delete(ident);
            --this.length;
            return item;
        }
        return null;
    }
    /**
     * Clear the entire data set.
     *
     * After the items are removed, the [[DataSet]] will trigger an event `remove` for all removed items. When a `senderId` is provided, this id will be passed with the triggered event to all subscribers.
     *
     * @param senderId - Sender id.
     *
     * @returns removedIds - The ids of all removed items.
     */
    clear(senderId) {
        const ids = [...this._data.keys()];
        const items = [];
        for (let i = 0, len = ids.length; i < len; i++) {
            items.push(this._data.get(ids[i]));
        }
        this._data.clear();
        this.length = 0;
        this._trigger("remove", { items: ids, oldData: items }, senderId);
        return ids;
    }
    /**
     * Find the item with maximum value of a specified field.
     *
     * @param field - Name of the property that should be searched for max value.
     *
     * @returns Item containing max value, or null if no items.
     */
    max(field) {
        let max = null;
        let maxField = null;
        for (const item of this._data.values()) {
            const itemField = item[field];
            if (typeof itemField === "number" &&
                (maxField == null || itemField > maxField)) {
                max = item;
                maxField = itemField;
            }
        }
        return max || null;
    }
    /**
     * Find the item with minimum value of a specified field.
     *
     * @param field - Name of the property that should be searched for min value.
     *
     * @returns Item containing min value, or null if no items.
     */
    min(field) {
        let min = null;
        let minField = null;
        for (const item of this._data.values()) {
            const itemField = item[field];
            if (typeof itemField === "number" &&
                (minField == null || itemField < minField)) {
                min = item;
                minField = itemField;
            }
        }
        return min || null;
    }
    /**
     * Find all distinct values of a specified field
     *
     * @param prop - The property name whose distinct values should be returned.
     *
     * @returns Unordered array containing all distinct values. Items without specified property are ignored.
     */
    distinct(prop) {
        const data = this._data;
        const itemIds = [...data.keys()];
        const values = [];
        let count = 0;
        for (let i = 0, len = itemIds.length; i < len; i++) {
            const id = itemIds[i];
            const item = data.get(id);
            const value = item[prop];
            let exists = false;
            for (let j = 0; j < count; j++) {
                if (values[j] == value) {
                    exists = true;
                    break;
                }
            }
            if (!exists && value !== undefined) {
                values[count] = value;
                count++;
            }
        }
        return values;
    }
    /**
     * Add a single item. Will fail when an item with the same id already exists.
     *
     * @param item - A new item to be added.
     *
     * @returns Added item's id. An id is generated when it is not present in the item.
     */
    _addItem(item) {
        const fullItem = ensureFullItem(item, this._idProp);
        const id = fullItem[this._idProp];
        // check whether this id is already taken
        if (this._data.has(id)) {
            // item already exists
            throw new Error("Cannot add item: item with id " + id + " already exists");
        }
        this._data.set(id, fullItem);
        ++this.length;
        return id;
    }
    /**
     * Update a single item: merge with existing item.
     * Will fail when the item has no id, or when there does not exist an item with the same id.
     *
     * @param update - The new item
     *
     * @returns The id of the updated item.
     */
    _updateItem(update) {
        const id = update[this._idProp];
        if (id == null) {
            throw new Error("Cannot update item: item has no id (item: " +
                JSON.stringify(update) +
                ")");
        }
        const item = this._data.get(id);
        if (!item) {
            // item doesn't exist
            throw new Error("Cannot update item: no item with id " + id + " found");
        }
        this._data.set(id, { ...item, ...update });
        return id;
    }
    /** @inheritDoc */
    stream(ids) {
        if (ids) {
            const data = this._data;
            return new DataStream({
                *[Symbol.iterator]() {
                    for (const id of ids) {
                        const item = data.get(id);
                        if (item != null) {
                            yield [id, item];
                        }
                    }
                },
            });
        }
        else {
            return new DataStream({
                [Symbol.iterator]: this._data.entries.bind(this._data),
            });
        }
    }
}

/**
 * DataView
 *
 * A DataView offers a filtered and/or formatted view on a DataSet. One can subscribe to changes in a DataView, and easily get filtered or formatted data without having to specify filters and field types all the time.
 *
 * ## Example
 * ```javascript
 * // create a DataSet
 * var data = new vis.DataSet();
 * data.add([
 *   {id: 1, text: 'item 1', date: new Date(2013, 6, 20), group: 1, first: true},
 *   {id: 2, text: 'item 2', date: '2013-06-23', group: 2},
 *   {id: 3, text: 'item 3', date: '2013-06-25', group: 2},
 *   {id: 4, text: 'item 4'}
 * ]);
 *
 * // create a DataView
 * // the view will only contain items having a property group with value 1,
 * // and will only output fields id, text, and date.
 * var view = new vis.DataView(data, {
 *   filter: function (item) {
 *     return (item.group == 1);
 *   },
 *   fields: ['id', 'text', 'date']
 * });
 *
 * // subscribe to any change in the DataView
 * view.on('*', function (event, properties, senderId) {
 *   console.log('event', event, properties);
 * });
 *
 * // update an item in the data set
 * data.update({id: 2, group: 1});
 *
 * // get all ids in the view
 * var ids = view.getIds();
 * console.log('ids', ids); // will output [1, 2]
 *
 * // get all items in the view
 * var items = view.get();
 * ```
 *
 * @typeParam Item - Item type that may or may not have an id.
 * @typeParam IdProp - Name of the property that contains the id.
 */
class DataView extends DataSetPart {
    /**
     * Create a DataView.
     *
     * @param data - The instance containing data (directly or indirectly).
     * @param options - Options to configure this data view.
     */
    constructor(data, options) {
        super();
        /** @inheritDoc */
        this.length = 0;
        this._ids = new Set(); // ids of the items currently in memory (just contains a boolean true)
        this._options = options || {};
        this._listener = this._onEvent.bind(this);
        this.setData(data);
    }
    /** @inheritDoc */
    get idProp() {
        return this.getDataSet().idProp;
    }
    // TODO: implement a function .config() to dynamically update things like configured filter
    // and trigger changes accordingly
    /**
     * Set a data source for the view.
     *
     * @param data - The instance containing data (directly or indirectly).
     *
     * @remarks
     * Note that when the data view is bound to a data set it won't be garbage
     * collected unless the data set is too. Use `dataView.setData(null)` or
     * `dataView.dispose()` to enable garbage collection before you lose the last
     * reference.
     */
    setData(data) {
        if (this._data) {
            // unsubscribe from current dataset
            if (this._data.off) {
                this._data.off("*", this._listener);
            }
            // trigger a remove of all items in memory
            const ids = this._data.getIds({ filter: this._options.filter });
            const items = this._data.get(ids);
            this._ids.clear();
            this.length = 0;
            this._trigger("remove", { items: ids, oldData: items });
        }
        if (data != null) {
            this._data = data;
            // trigger an add of all added items
            const ids = this._data.getIds({ filter: this._options.filter });
            for (let i = 0, len = ids.length; i < len; i++) {
                const id = ids[i];
                this._ids.add(id);
            }
            this.length = ids.length;
            this._trigger("add", { items: ids });
        }
        else {
            this._data = new DataSet();
        }
        // subscribe to new dataset
        if (this._data.on) {
            this._data.on("*", this._listener);
        }
    }
    /**
     * Refresh the DataView.
     * Useful when the DataView has a filter function containing a variable parameter.
     */
    refresh() {
        const ids = this._data.getIds({
            filter: this._options.filter,
        });
        const oldIds = [...this._ids];
        const newIds = {};
        const addedIds = [];
        const removedIds = [];
        const removedItems = [];
        // check for additions
        for (let i = 0, len = ids.length; i < len; i++) {
            const id = ids[i];
            newIds[id] = true;
            if (!this._ids.has(id)) {
                addedIds.push(id);
                this._ids.add(id);
            }
        }
        // check for removals
        for (let i = 0, len = oldIds.length; i < len; i++) {
            const id = oldIds[i];
            const item = this._data.get(id);
            if (item == null) {
                // @TODO: Investigate.
                // Doesn't happen during tests or examples.
                // Is it really impossible or could it eventually happen?
                // How to handle it if it does? The types guarantee non-nullable items.
                console.error("If you see this, report it please.");
            }
            else if (!newIds[id]) {
                removedIds.push(id);
                removedItems.push(item);
                this._ids.delete(id);
            }
        }
        this.length += addedIds.length - removedIds.length;
        // trigger events
        if (addedIds.length) {
            this._trigger("add", { items: addedIds });
        }
        if (removedIds.length) {
            this._trigger("remove", { items: removedIds, oldData: removedItems });
        }
    }
    /** @inheritDoc */
    get(first, second) {
        if (this._data == null) {
            return null;
        }
        // parse the arguments
        let ids = null;
        let options;
        if (isId(first) || Array.isArray(first)) {
            ids = first;
            options = second;
        }
        else {
            options = first;
        }
        // extend the options with the default options and provided options
        const viewOptions = Object.assign({}, this._options, options);
        // create a combined filter method when needed
        const thisFilter = this._options.filter;
        const optionsFilter = options && options.filter;
        if (thisFilter && optionsFilter) {
            viewOptions.filter = (item) => {
                return thisFilter(item) && optionsFilter(item);
            };
        }
        if (ids == null) {
            return this._data.get(viewOptions);
        }
        else {
            return this._data.get(ids, viewOptions);
        }
    }
    /** @inheritDoc */
    getIds(options) {
        if (this._data.length) {
            const defaultFilter = this._options.filter;
            const optionsFilter = options != null ? options.filter : null;
            let filter;
            if (optionsFilter) {
                if (defaultFilter) {
                    filter = (item) => {
                        return defaultFilter(item) && optionsFilter(item);
                    };
                }
                else {
                    filter = optionsFilter;
                }
            }
            else {
                filter = defaultFilter;
            }
            return this._data.getIds({
                filter: filter,
                order: options && options.order,
            });
        }
        else {
            return [];
        }
    }
    /** @inheritDoc */
    forEach(callback, options) {
        if (this._data) {
            const defaultFilter = this._options.filter;
            const optionsFilter = options && options.filter;
            let filter;
            if (optionsFilter) {
                if (defaultFilter) {
                    filter = function (item) {
                        return defaultFilter(item) && optionsFilter(item);
                    };
                }
                else {
                    filter = optionsFilter;
                }
            }
            else {
                filter = defaultFilter;
            }
            this._data.forEach(callback, {
                filter: filter,
                order: options && options.order,
            });
        }
    }
    /** @inheritDoc */
    map(callback, options) {
        if (this._data) {
            const defaultFilter = this._options.filter;
            const optionsFilter = options && options.filter;
            let filter;
            if (optionsFilter) {
                if (defaultFilter) {
                    filter = (item) => {
                        return defaultFilter(item) && optionsFilter(item);
                    };
                }
                else {
                    filter = optionsFilter;
                }
            }
            else {
                filter = defaultFilter;
            }
            return this._data.map(callback, {
                filter: filter,
                order: options && options.order,
            });
        }
        else {
            return [];
        }
    }
    /** @inheritDoc */
    getDataSet() {
        return this._data.getDataSet();
    }
    /** @inheritDoc */
    stream(ids) {
        return this._data.stream(ids || {
            [Symbol.iterator]: this._ids.keys.bind(this._ids),
        });
    }
    /**
     * Render the instance unusable prior to garbage collection.
     *
     * @remarks
     * The intention of this method is to help discover scenarios where the data
     * view is being used when the programmer thinks it has been garbage collected
     * already. It's stricter version of `dataView.setData(null)`.
     */
    dispose() {
        if (this._data?.off) {
            this._data.off("*", this._listener);
        }
        const message = "This data view has already been disposed of.";
        const replacement = {
            get: () => {
                throw new Error(message);
            },
            set: () => {
                throw new Error(message);
            },
            configurable: false,
        };
        for (const key of Reflect.ownKeys(DataView.prototype)) {
            Object.defineProperty(this, key, replacement);
        }
    }
    /**
     * Event listener. Will propagate all events from the connected data set to the subscribers of the DataView, but will filter the items and only trigger when there are changes in the filtered data set.
     *
     * @param event - The name of the event.
     * @param params - Parameters of the event.
     * @param senderId - Id supplied by the sender.
     */
    _onEvent(event, params, senderId) {
        if (!params || !params.items || !this._data) {
            return;
        }
        const ids = params.items;
        const addedIds = [];
        const updatedIds = [];
        const removedIds = [];
        const oldItems = [];
        const updatedItems = [];
        const removedItems = [];
        switch (event) {
            case "add":
                // filter the ids of the added items
                for (let i = 0, len = ids.length; i < len; i++) {
                    const id = ids[i];
                    const item = this.get(id);
                    if (item) {
                        this._ids.add(id);
                        addedIds.push(id);
                    }
                }
                break;
            case "update":
                // determine the event from the views viewpoint: an updated
                // item can be added, updated, or removed from this view.
                for (let i = 0, len = ids.length; i < len; i++) {
                    const id = ids[i];
                    const item = this.get(id);
                    if (item) {
                        if (this._ids.has(id)) {
                            updatedIds.push(id);
                            updatedItems.push(params.data[i]);
                            oldItems.push(params.oldData[i]);
                        }
                        else {
                            this._ids.add(id);
                            addedIds.push(id);
                        }
                    }
                    else {
                        if (this._ids.has(id)) {
                            this._ids.delete(id);
                            removedIds.push(id);
                            removedItems.push(params.oldData[i]);
                        }
                    }
                }
                break;
            case "remove":
                // filter the ids of the removed items
                for (let i = 0, len = ids.length; i < len; i++) {
                    const id = ids[i];
                    if (this._ids.has(id)) {
                        this._ids.delete(id);
                        removedIds.push(id);
                        removedItems.push(params.oldData[i]);
                    }
                }
                break;
        }
        this.length += addedIds.length - removedIds.length;
        if (addedIds.length) {
            this._trigger("add", { items: addedIds }, senderId);
        }
        if (updatedIds.length) {
            this._trigger("update", { items: updatedIds, oldData: oldItems, data: updatedItems }, senderId);
        }
        if (removedIds.length) {
            this._trigger("remove", { items: removedIds, oldData: removedItems }, senderId);
        }
    }
}

/**
 * Check that given value is compatible with Vis Data Set interface.
 *
 * @param idProp - The expected property to contain item id.
 * @param v - The value to be tested.
 *
 * @returns True if all expected values and methods match, false otherwise.
 */
function isDataSetLike(idProp, v) {
    return (typeof v === "object" &&
        v !== null &&
        idProp === v.idProp &&
        typeof v.add === "function" &&
        typeof v.clear === "function" &&
        typeof v.distinct === "function" &&
        typeof v.forEach === "function" &&
        typeof v.get === "function" &&
        typeof v.getDataSet === "function" &&
        typeof v.getIds === "function" &&
        typeof v.length === "number" &&
        typeof v.map === "function" &&
        typeof v.max === "function" &&
        typeof v.min === "function" &&
        typeof v.off === "function" &&
        typeof v.on === "function" &&
        typeof v.remove === "function" &&
        typeof v.setOptions === "function" &&
        typeof v.stream === "function" &&
        typeof v.update === "function" &&
        typeof v.updateOnly === "function");
}

/**
 * Check that given value is compatible with Vis Data View interface.
 *
 * @param idProp - The expected property to contain item id.
 * @param v - The value to be tested.
 *
 * @returns True if all expected values and methods match, false otherwise.
 */
function isDataViewLike(idProp, v) {
    return (typeof v === "object" &&
        v !== null &&
        idProp === v.idProp &&
        typeof v.forEach === "function" &&
        typeof v.get === "function" &&
        typeof v.getDataSet === "function" &&
        typeof v.getIds === "function" &&
        typeof v.length === "number" &&
        typeof v.map === "function" &&
        typeof v.off === "function" &&
        typeof v.on === "function" &&
        typeof v.stream === "function" &&
        isDataSetLike(idProp, v.getDataSet()));
}

/**
 * cssfilter
 *
 * @author 老雷<leizongmin@gmail.com>
 */

function getDefaultWhiteList () {
  // 白名单值说明：
  // true: 允许该属性
  // Function: function (val) { } 返回true表示允许该属性，其他值均表示不允许
  // RegExp: regexp.test(val) 返回true表示允许该属性，其他值均表示不允许
  // 除上面列出的值外均表示不允许
  var whiteList = {};

  whiteList['align-content'] = false; // default: auto
  whiteList['align-items'] = false; // default: auto
  whiteList['align-self'] = false; // default: auto
  whiteList['alignment-adjust'] = false; // default: auto
  whiteList['alignment-baseline'] = false; // default: baseline
  whiteList['all'] = false; // default: depending on individual properties
  whiteList['anchor-point'] = false; // default: none
  whiteList['animation'] = false; // default: depending on individual properties
  whiteList['animation-delay'] = false; // default: 0
  whiteList['animation-direction'] = false; // default: normal
  whiteList['animation-duration'] = false; // default: 0
  whiteList['animation-fill-mode'] = false; // default: none
  whiteList['animation-iteration-count'] = false; // default: 1
  whiteList['animation-name'] = false; // default: none
  whiteList['animation-play-state'] = false; // default: running
  whiteList['animation-timing-function'] = false; // default: ease
  whiteList['azimuth'] = false; // default: center
  whiteList['backface-visibility'] = false; // default: visible
  whiteList['background'] = true; // default: depending on individual properties
  whiteList['background-attachment'] = true; // default: scroll
  whiteList['background-clip'] = true; // default: border-box
  whiteList['background-color'] = true; // default: transparent
  whiteList['background-image'] = true; // default: none
  whiteList['background-origin'] = true; // default: padding-box
  whiteList['background-position'] = true; // default: 0% 0%
  whiteList['background-repeat'] = true; // default: repeat
  whiteList['background-size'] = true; // default: auto
  whiteList['baseline-shift'] = false; // default: baseline
  whiteList['binding'] = false; // default: none
  whiteList['bleed'] = false; // default: 6pt
  whiteList['bookmark-label'] = false; // default: content()
  whiteList['bookmark-level'] = false; // default: none
  whiteList['bookmark-state'] = false; // default: open
  whiteList['border'] = true; // default: depending on individual properties
  whiteList['border-bottom'] = true; // default: depending on individual properties
  whiteList['border-bottom-color'] = true; // default: current color
  whiteList['border-bottom-left-radius'] = true; // default: 0
  whiteList['border-bottom-right-radius'] = true; // default: 0
  whiteList['border-bottom-style'] = true; // default: none
  whiteList['border-bottom-width'] = true; // default: medium
  whiteList['border-collapse'] = true; // default: separate
  whiteList['border-color'] = true; // default: depending on individual properties
  whiteList['border-image'] = true; // default: none
  whiteList['border-image-outset'] = true; // default: 0
  whiteList['border-image-repeat'] = true; // default: stretch
  whiteList['border-image-slice'] = true; // default: 100%
  whiteList['border-image-source'] = true; // default: none
  whiteList['border-image-width'] = true; // default: 1
  whiteList['border-left'] = true; // default: depending on individual properties
  whiteList['border-left-color'] = true; // default: current color
  whiteList['border-left-style'] = true; // default: none
  whiteList['border-left-width'] = true; // default: medium
  whiteList['border-radius'] = true; // default: 0
  whiteList['border-right'] = true; // default: depending on individual properties
  whiteList['border-right-color'] = true; // default: current color
  whiteList['border-right-style'] = true; // default: none
  whiteList['border-right-width'] = true; // default: medium
  whiteList['border-spacing'] = true; // default: 0
  whiteList['border-style'] = true; // default: depending on individual properties
  whiteList['border-top'] = true; // default: depending on individual properties
  whiteList['border-top-color'] = true; // default: current color
  whiteList['border-top-left-radius'] = true; // default: 0
  whiteList['border-top-right-radius'] = true; // default: 0
  whiteList['border-top-style'] = true; // default: none
  whiteList['border-top-width'] = true; // default: medium
  whiteList['border-width'] = true; // default: depending on individual properties
  whiteList['bottom'] = false; // default: auto
  whiteList['box-decoration-break'] = true; // default: slice
  whiteList['box-shadow'] = true; // default: none
  whiteList['box-sizing'] = true; // default: content-box
  whiteList['box-snap'] = true; // default: none
  whiteList['box-suppress'] = true; // default: show
  whiteList['break-after'] = true; // default: auto
  whiteList['break-before'] = true; // default: auto
  whiteList['break-inside'] = true; // default: auto
  whiteList['caption-side'] = false; // default: top
  whiteList['chains'] = false; // default: none
  whiteList['clear'] = true; // default: none
  whiteList['clip'] = false; // default: auto
  whiteList['clip-path'] = false; // default: none
  whiteList['clip-rule'] = false; // default: nonzero
  whiteList['color'] = true; // default: implementation dependent
  whiteList['color-interpolation-filters'] = true; // default: auto
  whiteList['column-count'] = false; // default: auto
  whiteList['column-fill'] = false; // default: balance
  whiteList['column-gap'] = false; // default: normal
  whiteList['column-rule'] = false; // default: depending on individual properties
  whiteList['column-rule-color'] = false; // default: current color
  whiteList['column-rule-style'] = false; // default: medium
  whiteList['column-rule-width'] = false; // default: medium
  whiteList['column-span'] = false; // default: none
  whiteList['column-width'] = false; // default: auto
  whiteList['columns'] = false; // default: depending on individual properties
  whiteList['contain'] = false; // default: none
  whiteList['content'] = false; // default: normal
  whiteList['counter-increment'] = false; // default: none
  whiteList['counter-reset'] = false; // default: none
  whiteList['counter-set'] = false; // default: none
  whiteList['crop'] = false; // default: auto
  whiteList['cue'] = false; // default: depending on individual properties
  whiteList['cue-after'] = false; // default: none
  whiteList['cue-before'] = false; // default: none
  whiteList['cursor'] = false; // default: auto
  whiteList['direction'] = false; // default: ltr
  whiteList['display'] = true; // default: depending on individual properties
  whiteList['display-inside'] = true; // default: auto
  whiteList['display-list'] = true; // default: none
  whiteList['display-outside'] = true; // default: inline-level
  whiteList['dominant-baseline'] = false; // default: auto
  whiteList['elevation'] = false; // default: level
  whiteList['empty-cells'] = false; // default: show
  whiteList['filter'] = false; // default: none
  whiteList['flex'] = false; // default: depending on individual properties
  whiteList['flex-basis'] = false; // default: auto
  whiteList['flex-direction'] = false; // default: row
  whiteList['flex-flow'] = false; // default: depending on individual properties
  whiteList['flex-grow'] = false; // default: 0
  whiteList['flex-shrink'] = false; // default: 1
  whiteList['flex-wrap'] = false; // default: nowrap
  whiteList['float'] = false; // default: none
  whiteList['float-offset'] = false; // default: 0 0
  whiteList['flood-color'] = false; // default: black
  whiteList['flood-opacity'] = false; // default: 1
  whiteList['flow-from'] = false; // default: none
  whiteList['flow-into'] = false; // default: none
  whiteList['font'] = true; // default: depending on individual properties
  whiteList['font-family'] = true; // default: implementation dependent
  whiteList['font-feature-settings'] = true; // default: normal
  whiteList['font-kerning'] = true; // default: auto
  whiteList['font-language-override'] = true; // default: normal
  whiteList['font-size'] = true; // default: medium
  whiteList['font-size-adjust'] = true; // default: none
  whiteList['font-stretch'] = true; // default: normal
  whiteList['font-style'] = true; // default: normal
  whiteList['font-synthesis'] = true; // default: weight style
  whiteList['font-variant'] = true; // default: normal
  whiteList['font-variant-alternates'] = true; // default: normal
  whiteList['font-variant-caps'] = true; // default: normal
  whiteList['font-variant-east-asian'] = true; // default: normal
  whiteList['font-variant-ligatures'] = true; // default: normal
  whiteList['font-variant-numeric'] = true; // default: normal
  whiteList['font-variant-position'] = true; // default: normal
  whiteList['font-weight'] = true; // default: normal
  whiteList['grid'] = false; // default: depending on individual properties
  whiteList['grid-area'] = false; // default: depending on individual properties
  whiteList['grid-auto-columns'] = false; // default: auto
  whiteList['grid-auto-flow'] = false; // default: none
  whiteList['grid-auto-rows'] = false; // default: auto
  whiteList['grid-column'] = false; // default: depending on individual properties
  whiteList['grid-column-end'] = false; // default: auto
  whiteList['grid-column-start'] = false; // default: auto
  whiteList['grid-row'] = false; // default: depending on individual properties
  whiteList['grid-row-end'] = false; // default: auto
  whiteList['grid-row-start'] = false; // default: auto
  whiteList['grid-template'] = false; // default: depending on individual properties
  whiteList['grid-template-areas'] = false; // default: none
  whiteList['grid-template-columns'] = false; // default: none
  whiteList['grid-template-rows'] = false; // default: none
  whiteList['hanging-punctuation'] = false; // default: none
  whiteList['height'] = true; // default: auto
  whiteList['hyphens'] = false; // default: manual
  whiteList['icon'] = false; // default: auto
  whiteList['image-orientation'] = false; // default: auto
  whiteList['image-resolution'] = false; // default: normal
  whiteList['ime-mode'] = false; // default: auto
  whiteList['initial-letters'] = false; // default: normal
  whiteList['inline-box-align'] = false; // default: last
  whiteList['justify-content'] = false; // default: auto
  whiteList['justify-items'] = false; // default: auto
  whiteList['justify-self'] = false; // default: auto
  whiteList['left'] = false; // default: auto
  whiteList['letter-spacing'] = true; // default: normal
  whiteList['lighting-color'] = true; // default: white
  whiteList['line-box-contain'] = false; // default: block inline replaced
  whiteList['line-break'] = false; // default: auto
  whiteList['line-grid'] = false; // default: match-parent
  whiteList['line-height'] = false; // default: normal
  whiteList['line-snap'] = false; // default: none
  whiteList['line-stacking'] = false; // default: depending on individual properties
  whiteList['line-stacking-ruby'] = false; // default: exclude-ruby
  whiteList['line-stacking-shift'] = false; // default: consider-shifts
  whiteList['line-stacking-strategy'] = false; // default: inline-line-height
  whiteList['list-style'] = true; // default: depending on individual properties
  whiteList['list-style-image'] = true; // default: none
  whiteList['list-style-position'] = true; // default: outside
  whiteList['list-style-type'] = true; // default: disc
  whiteList['margin'] = true; // default: depending on individual properties
  whiteList['margin-bottom'] = true; // default: 0
  whiteList['margin-left'] = true; // default: 0
  whiteList['margin-right'] = true; // default: 0
  whiteList['margin-top'] = true; // default: 0
  whiteList['marker-offset'] = false; // default: auto
  whiteList['marker-side'] = false; // default: list-item
  whiteList['marks'] = false; // default: none
  whiteList['mask'] = false; // default: border-box
  whiteList['mask-box'] = false; // default: see individual properties
  whiteList['mask-box-outset'] = false; // default: 0
  whiteList['mask-box-repeat'] = false; // default: stretch
  whiteList['mask-box-slice'] = false; // default: 0 fill
  whiteList['mask-box-source'] = false; // default: none
  whiteList['mask-box-width'] = false; // default: auto
  whiteList['mask-clip'] = false; // default: border-box
  whiteList['mask-image'] = false; // default: none
  whiteList['mask-origin'] = false; // default: border-box
  whiteList['mask-position'] = false; // default: center
  whiteList['mask-repeat'] = false; // default: no-repeat
  whiteList['mask-size'] = false; // default: border-box
  whiteList['mask-source-type'] = false; // default: auto
  whiteList['mask-type'] = false; // default: luminance
  whiteList['max-height'] = true; // default: none
  whiteList['max-lines'] = false; // default: none
  whiteList['max-width'] = true; // default: none
  whiteList['min-height'] = true; // default: 0
  whiteList['min-width'] = true; // default: 0
  whiteList['move-to'] = false; // default: normal
  whiteList['nav-down'] = false; // default: auto
  whiteList['nav-index'] = false; // default: auto
  whiteList['nav-left'] = false; // default: auto
  whiteList['nav-right'] = false; // default: auto
  whiteList['nav-up'] = false; // default: auto
  whiteList['object-fit'] = false; // default: fill
  whiteList['object-position'] = false; // default: 50% 50%
  whiteList['opacity'] = false; // default: 1
  whiteList['order'] = false; // default: 0
  whiteList['orphans'] = false; // default: 2
  whiteList['outline'] = false; // default: depending on individual properties
  whiteList['outline-color'] = false; // default: invert
  whiteList['outline-offset'] = false; // default: 0
  whiteList['outline-style'] = false; // default: none
  whiteList['outline-width'] = false; // default: medium
  whiteList['overflow'] = false; // default: depending on individual properties
  whiteList['overflow-wrap'] = false; // default: normal
  whiteList['overflow-x'] = false; // default: visible
  whiteList['overflow-y'] = false; // default: visible
  whiteList['padding'] = true; // default: depending on individual properties
  whiteList['padding-bottom'] = true; // default: 0
  whiteList['padding-left'] = true; // default: 0
  whiteList['padding-right'] = true; // default: 0
  whiteList['padding-top'] = true; // default: 0
  whiteList['page'] = false; // default: auto
  whiteList['page-break-after'] = false; // default: auto
  whiteList['page-break-before'] = false; // default: auto
  whiteList['page-break-inside'] = false; // default: auto
  whiteList['page-policy'] = false; // default: start
  whiteList['pause'] = false; // default: implementation dependent
  whiteList['pause-after'] = false; // default: implementation dependent
  whiteList['pause-before'] = false; // default: implementation dependent
  whiteList['perspective'] = false; // default: none
  whiteList['perspective-origin'] = false; // default: 50% 50%
  whiteList['pitch'] = false; // default: medium
  whiteList['pitch-range'] = false; // default: 50
  whiteList['play-during'] = false; // default: auto
  whiteList['position'] = false; // default: static
  whiteList['presentation-level'] = false; // default: 0
  whiteList['quotes'] = false; // default: text
  whiteList['region-fragment'] = false; // default: auto
  whiteList['resize'] = false; // default: none
  whiteList['rest'] = false; // default: depending on individual properties
  whiteList['rest-after'] = false; // default: none
  whiteList['rest-before'] = false; // default: none
  whiteList['richness'] = false; // default: 50
  whiteList['right'] = false; // default: auto
  whiteList['rotation'] = false; // default: 0
  whiteList['rotation-point'] = false; // default: 50% 50%
  whiteList['ruby-align'] = false; // default: auto
  whiteList['ruby-merge'] = false; // default: separate
  whiteList['ruby-position'] = false; // default: before
  whiteList['shape-image-threshold'] = false; // default: 0.0
  whiteList['shape-outside'] = false; // default: none
  whiteList['shape-margin'] = false; // default: 0
  whiteList['size'] = false; // default: auto
  whiteList['speak'] = false; // default: auto
  whiteList['speak-as'] = false; // default: normal
  whiteList['speak-header'] = false; // default: once
  whiteList['speak-numeral'] = false; // default: continuous
  whiteList['speak-punctuation'] = false; // default: none
  whiteList['speech-rate'] = false; // default: medium
  whiteList['stress'] = false; // default: 50
  whiteList['string-set'] = false; // default: none
  whiteList['tab-size'] = false; // default: 8
  whiteList['table-layout'] = false; // default: auto
  whiteList['text-align'] = true; // default: start
  whiteList['text-align-last'] = true; // default: auto
  whiteList['text-combine-upright'] = true; // default: none
  whiteList['text-decoration'] = true; // default: none
  whiteList['text-decoration-color'] = true; // default: currentColor
  whiteList['text-decoration-line'] = true; // default: none
  whiteList['text-decoration-skip'] = true; // default: objects
  whiteList['text-decoration-style'] = true; // default: solid
  whiteList['text-emphasis'] = true; // default: depending on individual properties
  whiteList['text-emphasis-color'] = true; // default: currentColor
  whiteList['text-emphasis-position'] = true; // default: over right
  whiteList['text-emphasis-style'] = true; // default: none
  whiteList['text-height'] = true; // default: auto
  whiteList['text-indent'] = true; // default: 0
  whiteList['text-justify'] = true; // default: auto
  whiteList['text-orientation'] = true; // default: mixed
  whiteList['text-overflow'] = true; // default: clip
  whiteList['text-shadow'] = true; // default: none
  whiteList['text-space-collapse'] = true; // default: collapse
  whiteList['text-transform'] = true; // default: none
  whiteList['text-underline-position'] = true; // default: auto
  whiteList['text-wrap'] = true; // default: normal
  whiteList['top'] = false; // default: auto
  whiteList['transform'] = false; // default: none
  whiteList['transform-origin'] = false; // default: 50% 50% 0
  whiteList['transform-style'] = false; // default: flat
  whiteList['transition'] = false; // default: depending on individual properties
  whiteList['transition-delay'] = false; // default: 0s
  whiteList['transition-duration'] = false; // default: 0s
  whiteList['transition-property'] = false; // default: all
  whiteList['transition-timing-function'] = false; // default: ease
  whiteList['unicode-bidi'] = false; // default: normal
  whiteList['vertical-align'] = false; // default: baseline
  whiteList['visibility'] = false; // default: visible
  whiteList['voice-balance'] = false; // default: center
  whiteList['voice-duration'] = false; // default: auto
  whiteList['voice-family'] = false; // default: implementation dependent
  whiteList['voice-pitch'] = false; // default: medium
  whiteList['voice-range'] = false; // default: medium
  whiteList['voice-rate'] = false; // default: normal
  whiteList['voice-stress'] = false; // default: normal
  whiteList['voice-volume'] = false; // default: medium
  whiteList['volume'] = false; // default: medium
  whiteList['white-space'] = false; // default: normal
  whiteList['widows'] = false; // default: 2
  whiteList['width'] = true; // default: auto
  whiteList['will-change'] = false; // default: auto
  whiteList['word-break'] = true; // default: normal
  whiteList['word-spacing'] = true; // default: normal
  whiteList['word-wrap'] = true; // default: normal
  whiteList['wrap-flow'] = false; // default: auto
  whiteList['wrap-through'] = false; // default: wrap
  whiteList['writing-mode'] = false; // default: horizontal-tb
  whiteList['z-index'] = false; // default: auto

  return whiteList;
}


/**
 * 匹配到白名单上的一个属性时
 *
 * @param {String} name
 * @param {String} value
 * @param {Object} options
 * @return {String}
 */
function onAttr (name, value, options) {
  // do nothing
}

/**
 * 匹配到不在白名单上的一个属性时
 *
 * @param {String} name
 * @param {String} value
 * @param {Object} options
 * @return {String}
 */
function onIgnoreAttr (name, value, options) {
  // do nothing
}

var REGEXP_URL_JAVASCRIPT = /javascript\s*\:/img;

/**
 * 过滤属性值
 *
 * @param {String} name
 * @param {String} value
 * @return {String}
 */
function safeAttrValue(name, value) {
  if (REGEXP_URL_JAVASCRIPT.test(value)) return '';
  return value;
}


var whiteList = getDefaultWhiteList();
var getDefaultWhiteList_1 = getDefaultWhiteList;
var onAttr_1 = onAttr;
var onIgnoreAttr_1 = onIgnoreAttr;
var safeAttrValue_1 = safeAttrValue;

var _default = {
	whiteList: whiteList,
	getDefaultWhiteList: getDefaultWhiteList_1,
	onAttr: onAttr_1,
	onIgnoreAttr: onIgnoreAttr_1,
	safeAttrValue: safeAttrValue_1
};

var util = {
  indexOf: function (arr, item) {
    var i, j;
    if (Array.prototype.indexOf) {
      return arr.indexOf(item);
    }
    for (i = 0, j = arr.length; i < j; i++) {
      if (arr[i] === item) {
        return i;
      }
    }
    return -1;
  },
  forEach: function (arr, fn, scope) {
    var i, j;
    if (Array.prototype.forEach) {
      return arr.forEach(fn, scope);
    }
    for (i = 0, j = arr.length; i < j; i++) {
      fn.call(scope, arr[i], i, arr);
    }
  },
  trim: function (str) {
    if (String.prototype.trim) {
      return str.trim();
    }
    return str.replace(/(^\s*)|(\s*$)/g, '');
  },
  trimRight: function (str) {
    if (String.prototype.trimRight) {
      return str.trimRight();
    }
    return str.replace(/(\s*$)/g, '');
  }
};

/**
 * cssfilter
 *
 * @author 老雷<leizongmin@gmail.com>
 */




/**
 * 解析style
 *
 * @param {String} css
 * @param {Function} onAttr 处理属性的函数
 *   参数格式： function (sourcePosition, position, name, value, source)
 * @return {String}
 */
function parseStyle (css, onAttr) {
  css = util.trimRight(css);
  if (css[css.length - 1] !== ';') css += ';';
  var cssLength = css.length;
  var isParenthesisOpen = false;
  var lastPos = 0;
  var i = 0;
  var retCSS = '';

  function addNewAttr () {
    // 如果没有正常的闭合圆括号，则直接忽略当前属性
    if (!isParenthesisOpen) {
      var source = util.trim(css.slice(lastPos, i));
      var j = source.indexOf(':');
      if (j !== -1) {
        var name = util.trim(source.slice(0, j));
        var value = util.trim(source.slice(j + 1));
        // 必须有属性名称
        if (name) {
          var ret = onAttr(lastPos, retCSS.length, name, value, source);
          if (ret) retCSS += ret + '; ';
        }
      }
    }
    lastPos = i + 1;
  }

  for (; i < cssLength; i++) {
    var c = css[i];
    if (c === '/' && css[i + 1] === '*') {
      // 备注开始
      var j = css.indexOf('*/', i + 2);
      // 如果没有正常的备注结束，则后面的部分全部跳过
      if (j === -1) break;
      // 直接将当前位置调到备注结尾，并且初始化状态
      i = j + 1;
      lastPos = i + 1;
      isParenthesisOpen = false;
    } else if (c === '(') {
      isParenthesisOpen = true;
    } else if (c === ')') {
      isParenthesisOpen = false;
    } else if (c === ';') {
      if (isParenthesisOpen) ; else {
        addNewAttr();
      }
    } else if (c === '\n') {
      addNewAttr();
    }
  }

  return util.trim(retCSS);
}

var parser = parseStyle;

/**
 * cssfilter
 *
 * @author 老雷<leizongmin@gmail.com>
 */






/**
 * 返回值是否为空
 *
 * @param {Object} obj
 * @return {Boolean}
 */
function isNull (obj) {
  return (obj === undefined || obj === null);
}

/**
 * 浅拷贝对象
 *
 * @param {Object} obj
 * @return {Object}
 */
function shallowCopyObject (obj) {
  var ret = {};
  for (var i in obj) {
    ret[i] = obj[i];
  }
  return ret;
}

/**
 * 创建CSS过滤器
 *
 * @param {Object} options
 *   - {Object} whiteList
 *   - {Function} onAttr
 *   - {Function} onIgnoreAttr
 *   - {Function} safeAttrValue
 */
function FilterCSS (options) {
  options = shallowCopyObject(options || {});
  options.whiteList = options.whiteList || _default.whiteList;
  options.onAttr = options.onAttr || _default.onAttr;
  options.onIgnoreAttr = options.onIgnoreAttr || _default.onIgnoreAttr;
  options.safeAttrValue = options.safeAttrValue || _default.safeAttrValue;
  this.options = options;
}

FilterCSS.prototype.process = function (css) {
  // 兼容各种奇葩输入
  css = css || '';
  css = css.toString();
  if (!css) return '';

  var me = this;
  var options = me.options;
  var whiteList = options.whiteList;
  var onAttr = options.onAttr;
  var onIgnoreAttr = options.onIgnoreAttr;
  var safeAttrValue = options.safeAttrValue;

  var retCSS = parser(css, function (sourcePosition, position, name, value, source) {

    var check = whiteList[name];
    var isWhite = false;
    if (check === true) isWhite = check;
    else if (typeof check === 'function') isWhite = check(value);
    else if (check instanceof RegExp) isWhite = check.test(value);
    if (isWhite !== true) isWhite = false;

    // 如果过滤后 value 为空则直接忽略
    value = safeAttrValue(name, value);
    if (!value) return;

    var opts = {
      position: position,
      sourcePosition: sourcePosition,
      source: source,
      isWhite: isWhite
    };

    if (isWhite) {

      var ret = onAttr(name, value, opts);
      if (isNull(ret)) {
        return name + ':' + value;
      } else {
        return ret;
      }

    } else {

      var ret = onIgnoreAttr(name, value, opts);
      if (!isNull(ret)) {
        return ret;
      }

    }
  });

  return retCSS;
};


var css = FilterCSS;

var lib = createCommonjsModule(function (module, exports) {
/**
 * cssfilter
 *
 * @author 老雷<leizongmin@gmail.com>
 */





/**
 * XSS过滤
 *
 * @param {String} css 要过滤的CSS代码
 * @param {Object} options 选项：whiteList, onAttr, onIgnoreAttr
 * @return {String}
 */
function filterCSS (html, options) {
  var xss = new css(options);
  return xss.process(html);
}


// 输出
exports = module.exports = filterCSS;
exports.FilterCSS = css;
for (var i in _default) exports[i] = _default[i];

// 在浏览器端使用
if (typeof window !== 'undefined') {
  window.filterCSS = module.exports;
}
});

var util$2 = {
  indexOf: function(arr, item) {
    var i, j;
    if (Array.prototype.indexOf) {
      return arr.indexOf(item);
    }
    for (i = 0, j = arr.length; i < j; i++) {
      if (arr[i] === item) {
        return i;
      }
    }
    return -1;
  },
  forEach: function(arr, fn, scope) {
    var i, j;
    if (Array.prototype.forEach) {
      return arr.forEach(fn, scope);
    }
    for (i = 0, j = arr.length; i < j; i++) {
      fn.call(scope, arr[i], i, arr);
    }
  },
  trim: function(str) {
    if (String.prototype.trim) {
      return str.trim();
    }
    return str.replace(/(^\s*)|(\s*$)/g, "");
  },
  spaceIndex: function(str) {
    var reg = /\s|\n|\t/;
    var match = reg.exec(str);
    return match ? match.index : -1;
  }
};

/**
 * default settings
 *
 * @author Zongmin Lei<leizongmin@gmail.com>
 */

var FilterCSS$1 = lib.FilterCSS;
var getDefaultCSSWhiteList = lib.getDefaultWhiteList;


function getDefaultWhiteList$1() {
  return {
    a: ["target", "href", "title"],
    abbr: ["title"],
    address: [],
    area: ["shape", "coords", "href", "alt"],
    article: [],
    aside: [],
    audio: ["autoplay", "controls", "loop", "preload", "src"],
    b: [],
    bdi: ["dir"],
    bdo: ["dir"],
    big: [],
    blockquote: ["cite"],
    br: [],
    caption: [],
    center: [],
    cite: [],
    code: [],
    col: ["align", "valign", "span", "width"],
    colgroup: ["align", "valign", "span", "width"],
    dd: [],
    del: ["datetime"],
    details: ["open"],
    div: [],
    dl: [],
    dt: [],
    em: [],
    font: ["color", "size", "face"],
    footer: [],
    h1: [],
    h2: [],
    h3: [],
    h4: [],
    h5: [],
    h6: [],
    header: [],
    hr: [],
    i: [],
    img: ["src", "alt", "title", "width", "height"],
    ins: ["datetime"],
    li: [],
    mark: [],
    nav: [],
    ol: [],
    p: [],
    pre: [],
    s: [],
    section: [],
    small: [],
    span: [],
    sub: [],
    sup: [],
    strong: [],
    table: ["width", "border", "align", "valign"],
    tbody: ["align", "valign"],
    td: ["width", "rowspan", "colspan", "align", "valign"],
    tfoot: ["align", "valign"],
    th: ["width", "rowspan", "colspan", "align", "valign"],
    thead: ["align", "valign"],
    tr: ["rowspan", "align", "valign"],
    tt: [],
    u: [],
    ul: [],
    video: ["autoplay", "controls", "loop", "preload", "src", "height", "width"]
  };
}

var defaultCSSFilter = new FilterCSS$1();

/**
 * default onTag function
 *
 * @param {String} tag
 * @param {String} html
 * @param {Object} options
 * @return {String}
 */
function onTag(tag, html, options) {
  // do nothing
}

/**
 * default onIgnoreTag function
 *
 * @param {String} tag
 * @param {String} html
 * @param {Object} options
 * @return {String}
 */
function onIgnoreTag(tag, html, options) {
  // do nothing
}

/**
 * default onTagAttr function
 *
 * @param {String} tag
 * @param {String} name
 * @param {String} value
 * @return {String}
 */
function onTagAttr(tag, name, value) {
  // do nothing
}

/**
 * default onIgnoreTagAttr function
 *
 * @param {String} tag
 * @param {String} name
 * @param {String} value
 * @return {String}
 */
function onIgnoreTagAttr(tag, name, value) {
  // do nothing
}

/**
 * default escapeHtml function
 *
 * @param {String} html
 */
function escapeHtml(html) {
  return html.replace(REGEXP_LT, "&lt;").replace(REGEXP_GT, "&gt;");
}

/**
 * default safeAttrValue function
 *
 * @param {String} tag
 * @param {String} name
 * @param {String} value
 * @param {Object} cssFilter
 * @return {String}
 */
function safeAttrValue$1(tag, name, value, cssFilter) {
  // unescape attribute value firstly
  value = friendlyAttrValue(value);

  if (name === "href" || name === "src") {
    // filter `href` and `src` attribute
    // only allow the value that starts with `http://` | `https://` | `mailto:` | `/` | `#`
    value = util$2.trim(value);
    if (value === "#") return "#";
    if (
      !(
        value.substr(0, 7) === "http://" ||
        value.substr(0, 8) === "https://" ||
        value.substr(0, 7) === "mailto:" ||
        value.substr(0, 4) === "tel:" ||
        value.substr(0, 11) === "data:image/" ||
        value.substr(0, 6) === "ftp://" ||
        value.substr(0, 2) === "./" ||
        value.substr(0, 3) === "../" ||
        value[0] === "#" ||
        value[0] === "/"
      )
    ) {
      return "";
    }
  } else if (name === "background") {
    // filter `background` attribute (maybe no use)
    // `javascript:`
    REGEXP_DEFAULT_ON_TAG_ATTR_4.lastIndex = 0;
    if (REGEXP_DEFAULT_ON_TAG_ATTR_4.test(value)) {
      return "";
    }
  } else if (name === "style") {
    // `expression()`
    REGEXP_DEFAULT_ON_TAG_ATTR_7.lastIndex = 0;
    if (REGEXP_DEFAULT_ON_TAG_ATTR_7.test(value)) {
      return "";
    }
    // `url()`
    REGEXP_DEFAULT_ON_TAG_ATTR_8.lastIndex = 0;
    if (REGEXP_DEFAULT_ON_TAG_ATTR_8.test(value)) {
      REGEXP_DEFAULT_ON_TAG_ATTR_4.lastIndex = 0;
      if (REGEXP_DEFAULT_ON_TAG_ATTR_4.test(value)) {
        return "";
      }
    }
    if (cssFilter !== false) {
      cssFilter = cssFilter || defaultCSSFilter;
      value = cssFilter.process(value);
    }
  }

  // escape `<>"` before returns
  value = escapeAttrValue(value);
  return value;
}

// RegExp list
var REGEXP_LT = /</g;
var REGEXP_GT = />/g;
var REGEXP_QUOTE = /"/g;
var REGEXP_QUOTE_2 = /&quot;/g;
var REGEXP_ATTR_VALUE_1 = /&#([a-zA-Z0-9]*);?/gim;
var REGEXP_ATTR_VALUE_COLON = /&colon;?/gim;
var REGEXP_ATTR_VALUE_NEWLINE = /&newline;?/gim;
var REGEXP_DEFAULT_ON_TAG_ATTR_4 = /((j\s*a\s*v\s*a|v\s*b|l\s*i\s*v\s*e)\s*s\s*c\s*r\s*i\s*p\s*t\s*|m\s*o\s*c\s*h\s*a)\:/gi;
var REGEXP_DEFAULT_ON_TAG_ATTR_7 = /e\s*x\s*p\s*r\s*e\s*s\s*s\s*i\s*o\s*n\s*\(.*/gi;
var REGEXP_DEFAULT_ON_TAG_ATTR_8 = /u\s*r\s*l\s*\(.*/gi;

/**
 * escape doube quote
 *
 * @param {String} str
 * @return {String} str
 */
function escapeQuote(str) {
  return str.replace(REGEXP_QUOTE, "&quot;");
}

/**
 * unescape double quote
 *
 * @param {String} str
 * @return {String} str
 */
function unescapeQuote(str) {
  return str.replace(REGEXP_QUOTE_2, '"');
}

/**
 * escape html entities
 *
 * @param {String} str
 * @return {String}
 */
function escapeHtmlEntities(str) {
  return str.replace(REGEXP_ATTR_VALUE_1, function replaceUnicode(str, code) {
    return code[0] === "x" || code[0] === "X"
      ? String.fromCharCode(parseInt(code.substr(1), 16))
      : String.fromCharCode(parseInt(code, 10));
  });
}

/**
 * escape html5 new danger entities
 *
 * @param {String} str
 * @return {String}
 */
function escapeDangerHtml5Entities(str) {
  return str
    .replace(REGEXP_ATTR_VALUE_COLON, ":")
    .replace(REGEXP_ATTR_VALUE_NEWLINE, " ");
}

/**
 * clear nonprintable characters
 *
 * @param {String} str
 * @return {String}
 */
function clearNonPrintableCharacter(str) {
  var str2 = "";
  for (var i = 0, len = str.length; i < len; i++) {
    str2 += str.charCodeAt(i) < 32 ? " " : str.charAt(i);
  }
  return util$2.trim(str2);
}

/**
 * get friendly attribute value
 *
 * @param {String} str
 * @return {String}
 */
function friendlyAttrValue(str) {
  str = unescapeQuote(str);
  str = escapeHtmlEntities(str);
  str = escapeDangerHtml5Entities(str);
  str = clearNonPrintableCharacter(str);
  return str;
}

/**
 * unescape attribute value
 *
 * @param {String} str
 * @return {String}
 */
function escapeAttrValue(str) {
  str = escapeQuote(str);
  str = escapeHtml(str);
  return str;
}

/**
 * `onIgnoreTag` function for removing all the tags that are not in whitelist
 */
function onIgnoreTagStripAll() {
  return "";
}

/**
 * remove tag body
 * specify a `tags` list, if the tag is not in the `tags` list then process by the specify function (optional)
 *
 * @param {array} tags
 * @param {function} next
 */
function StripTagBody(tags, next) {
  if (typeof next !== "function") {
    next = function() {};
  }

  var isRemoveAllTag = !Array.isArray(tags);
  function isRemoveTag(tag) {
    if (isRemoveAllTag) return true;
    return util$2.indexOf(tags, tag) !== -1;
  }

  var removeList = [];
  var posStart = false;

  return {
    onIgnoreTag: function(tag, html, options) {
      if (isRemoveTag(tag)) {
        if (options.isClosing) {
          var ret = "[/removed]";
          var end = options.position + ret.length;
          removeList.push([
            posStart !== false ? posStart : options.position,
            end
          ]);
          posStart = false;
          return ret;
        } else {
          if (!posStart) {
            posStart = options.position;
          }
          return "[removed]";
        }
      } else {
        return next(tag, html, options);
      }
    },
    remove: function(html) {
      var rethtml = "";
      var lastPos = 0;
      util$2.forEach(removeList, function(pos) {
        rethtml += html.slice(lastPos, pos[0]);
        lastPos = pos[1];
      });
      rethtml += html.slice(lastPos);
      return rethtml;
    }
  };
}

/**
 * remove html comments
 *
 * @param {String} html
 * @return {String}
 */
function stripCommentTag(html) {
  return html.replace(STRIP_COMMENT_TAG_REGEXP, "");
}
var STRIP_COMMENT_TAG_REGEXP = /<!--[\s\S]*?-->/g;

/**
 * remove invisible characters
 *
 * @param {String} html
 * @return {String}
 */
function stripBlankChar(html) {
  var chars = html.split("");
  chars = chars.filter(function(char) {
    var c = char.charCodeAt(0);
    if (c === 127) return false;
    if (c <= 31) {
      if (c === 10 || c === 13) return true;
      return false;
    }
    return true;
  });
  return chars.join("");
}

var whiteList$1 = getDefaultWhiteList$1();
var getDefaultWhiteList_1$1 = getDefaultWhiteList$1;
var onTag_1 = onTag;
var onIgnoreTag_1 = onIgnoreTag;
var onTagAttr_1 = onTagAttr;
var onIgnoreTagAttr_1 = onIgnoreTagAttr;
var safeAttrValue_1$1 = safeAttrValue$1;
var escapeHtml_1 = escapeHtml;
var escapeQuote_1 = escapeQuote;
var unescapeQuote_1 = unescapeQuote;
var escapeHtmlEntities_1 = escapeHtmlEntities;
var escapeDangerHtml5Entities_1 = escapeDangerHtml5Entities;
var clearNonPrintableCharacter_1 = clearNonPrintableCharacter;
var friendlyAttrValue_1 = friendlyAttrValue;
var escapeAttrValue_1 = escapeAttrValue;
var onIgnoreTagStripAll_1 = onIgnoreTagStripAll;
var StripTagBody_1 = StripTagBody;
var stripCommentTag_1 = stripCommentTag;
var stripBlankChar_1 = stripBlankChar;
var cssFilter = defaultCSSFilter;
var getDefaultCSSWhiteList_1 = getDefaultCSSWhiteList;

var _default$1 = {
	whiteList: whiteList$1,
	getDefaultWhiteList: getDefaultWhiteList_1$1,
	onTag: onTag_1,
	onIgnoreTag: onIgnoreTag_1,
	onTagAttr: onTagAttr_1,
	onIgnoreTagAttr: onIgnoreTagAttr_1,
	safeAttrValue: safeAttrValue_1$1,
	escapeHtml: escapeHtml_1,
	escapeQuote: escapeQuote_1,
	unescapeQuote: unescapeQuote_1,
	escapeHtmlEntities: escapeHtmlEntities_1,
	escapeDangerHtml5Entities: escapeDangerHtml5Entities_1,
	clearNonPrintableCharacter: clearNonPrintableCharacter_1,
	friendlyAttrValue: friendlyAttrValue_1,
	escapeAttrValue: escapeAttrValue_1,
	onIgnoreTagStripAll: onIgnoreTagStripAll_1,
	StripTagBody: StripTagBody_1,
	stripCommentTag: stripCommentTag_1,
	stripBlankChar: stripBlankChar_1,
	cssFilter: cssFilter,
	getDefaultCSSWhiteList: getDefaultCSSWhiteList_1
};

/**
 * Simple HTML Parser
 *
 * @author Zongmin Lei<leizongmin@gmail.com>
 */



/**
 * get tag name
 *
 * @param {String} html e.g. '<a hef="#">'
 * @return {String}
 */
function getTagName(html) {
  var i = util$2.spaceIndex(html);
  if (i === -1) {
    var tagName = html.slice(1, -1);
  } else {
    var tagName = html.slice(1, i + 1);
  }
  tagName = util$2.trim(tagName).toLowerCase();
  if (tagName.slice(0, 1) === "/") tagName = tagName.slice(1);
  if (tagName.slice(-1) === "/") tagName = tagName.slice(0, -1);
  return tagName;
}

/**
 * is close tag?
 *
 * @param {String} html 如：'<a hef="#">'
 * @return {Boolean}
 */
function isClosing(html) {
  return html.slice(0, 2) === "</";
}

/**
 * parse input html and returns processed html
 *
 * @param {String} html
 * @param {Function} onTag e.g. function (sourcePosition, position, tag, html, isClosing)
 * @param {Function} escapeHtml
 * @return {String}
 */
function parseTag(html, onTag, escapeHtml) {

  var rethtml = "";
  var lastPos = 0;
  var tagStart = false;
  var quoteStart = false;
  var currentPos = 0;
  var len = html.length;
  var currentTagName = "";
  var currentHtml = "";

  chariterator: for (currentPos = 0; currentPos < len; currentPos++) {
    var c = html.charAt(currentPos);
    if (tagStart === false) {
      if (c === "<") {
        tagStart = currentPos;
        continue;
      }
    } else {
      if (quoteStart === false) {
        if (c === "<") {
          rethtml += escapeHtml(html.slice(lastPos, currentPos));
          tagStart = currentPos;
          lastPos = currentPos;
          continue;
        }
        if (c === ">") {
          rethtml += escapeHtml(html.slice(lastPos, tagStart));
          currentHtml = html.slice(tagStart, currentPos + 1);
          currentTagName = getTagName(currentHtml);
          rethtml += onTag(
            tagStart,
            rethtml.length,
            currentTagName,
            currentHtml,
            isClosing(currentHtml)
          );
          lastPos = currentPos + 1;
          tagStart = false;
          continue;
        }
        if ((c === '"' || c === "'")) {
          var i = 1;
          var ic = html.charAt(currentPos - i);

          while ((ic === " ") || (ic === "=")) {
            if (ic === "=") {
              quoteStart = c;
              continue chariterator;
            }
            ic = html.charAt(currentPos - ++i);
          }
        }
      } else {
        if (c === quoteStart) {
          quoteStart = false;
          continue;
        }
      }
    }
  }
  if (lastPos < html.length) {
    rethtml += escapeHtml(html.substr(lastPos));
  }

  return rethtml;
}

var REGEXP_ILLEGAL_ATTR_NAME = /[^a-zA-Z0-9_:\.\-]/gim;

/**
 * parse input attributes and returns processed attributes
 *
 * @param {String} html e.g. `href="#" target="_blank"`
 * @param {Function} onAttr e.g. `function (name, value)`
 * @return {String}
 */
function parseAttr(html, onAttr) {

  var lastPos = 0;
  var retAttrs = [];
  var tmpName = false;
  var len = html.length;

  function addAttr(name, value) {
    name = util$2.trim(name);
    name = name.replace(REGEXP_ILLEGAL_ATTR_NAME, "").toLowerCase();
    if (name.length < 1) return;
    var ret = onAttr(name, value || "");
    if (ret) retAttrs.push(ret);
  }

  // 逐个分析字符
  for (var i = 0; i < len; i++) {
    var c = html.charAt(i);
    var v, j;
    if (tmpName === false && c === "=") {
      tmpName = html.slice(lastPos, i);
      lastPos = i + 1;
      continue;
    }
    if (tmpName !== false) {
      if (
        i === lastPos &&
        (c === '"' || c === "'") &&
        html.charAt(i - 1) === "="
      ) {
        j = html.indexOf(c, i + 1);
        if (j === -1) {
          break;
        } else {
          v = util$2.trim(html.slice(lastPos + 1, j));
          addAttr(tmpName, v);
          tmpName = false;
          i = j;
          lastPos = i + 1;
          continue;
        }
      }
    }
    if (/\s|\n|\t/.test(c)) {
      html = html.replace(/\s|\n|\t/g, " ");
      if (tmpName === false) {
        j = findNextEqual(html, i);
        if (j === -1) {
          v = util$2.trim(html.slice(lastPos, i));
          addAttr(v);
          tmpName = false;
          lastPos = i + 1;
          continue;
        } else {
          i = j - 1;
          continue;
        }
      } else {
        j = findBeforeEqual(html, i - 1);
        if (j === -1) {
          v = util$2.trim(html.slice(lastPos, i));
          v = stripQuoteWrap(v);
          addAttr(tmpName, v);
          tmpName = false;
          lastPos = i + 1;
          continue;
        } else {
          continue;
        }
      }
    }
  }

  if (lastPos < html.length) {
    if (tmpName === false) {
      addAttr(html.slice(lastPos));
    } else {
      addAttr(tmpName, stripQuoteWrap(util$2.trim(html.slice(lastPos))));
    }
  }

  return util$2.trim(retAttrs.join(" "));
}

function findNextEqual(str, i) {
  for (; i < str.length; i++) {
    var c = str[i];
    if (c === " ") continue;
    if (c === "=") return i;
    return -1;
  }
}

function findBeforeEqual(str, i) {
  for (; i > 0; i--) {
    var c = str[i];
    if (c === " ") continue;
    if (c === "=") return i;
    return -1;
  }
}

function isQuoteWrapString(text) {
  if (
    (text[0] === '"' && text[text.length - 1] === '"') ||
    (text[0] === "'" && text[text.length - 1] === "'")
  ) {
    return true;
  } else {
    return false;
  }
}

function stripQuoteWrap(text) {
  if (isQuoteWrapString(text)) {
    return text.substr(1, text.length - 2);
  } else {
    return text;
  }
}

var parseTag_1 = parseTag;
var parseAttr_1 = parseAttr;

var parser$1 = {
	parseTag: parseTag_1,
	parseAttr: parseAttr_1
};

/**
 * filter xss
 *
 * @author Zongmin Lei<leizongmin@gmail.com>
 */

var FilterCSS$2 = lib.FilterCSS;


var parseTag$1 = parser$1.parseTag;
var parseAttr$1 = parser$1.parseAttr;


/**
 * returns `true` if the input value is `undefined` or `null`
 *
 * @param {Object} obj
 * @return {Boolean}
 */
function isNull$1(obj) {
  return obj === undefined || obj === null;
}

/**
 * get attributes for a tag
 *
 * @param {String} html
 * @return {Object}
 *   - {String} html
 *   - {Boolean} closing
 */
function getAttrs(html) {
  var i = util$2.spaceIndex(html);
  if (i === -1) {
    return {
      html: "",
      closing: html[html.length - 2] === "/"
    };
  }
  html = util$2.trim(html.slice(i + 1, -1));
  var isClosing = html[html.length - 1] === "/";
  if (isClosing) html = util$2.trim(html.slice(0, -1));
  return {
    html: html,
    closing: isClosing
  };
}

/**
 * shallow copy
 *
 * @param {Object} obj
 * @return {Object}
 */
function shallowCopyObject$1(obj) {
  var ret = {};
  for (var i in obj) {
    ret[i] = obj[i];
  }
  return ret;
}

/**
 * FilterXSS class
 *
 * @param {Object} options
 *        whiteList, onTag, onTagAttr, onIgnoreTag,
 *        onIgnoreTagAttr, safeAttrValue, escapeHtml
 *        stripIgnoreTagBody, allowCommentTag, stripBlankChar
 *        css{whiteList, onAttr, onIgnoreAttr} `css=false` means don't use `cssfilter`
 */
function FilterXSS(options) {
  options = shallowCopyObject$1(options || {});

  if (options.stripIgnoreTag) {
    if (options.onIgnoreTag) {
      console.error(
        'Notes: cannot use these two options "stripIgnoreTag" and "onIgnoreTag" at the same time'
      );
    }
    options.onIgnoreTag = _default$1.onIgnoreTagStripAll;
  }

  options.whiteList = options.whiteList || _default$1.whiteList;
  options.onTag = options.onTag || _default$1.onTag;
  options.onTagAttr = options.onTagAttr || _default$1.onTagAttr;
  options.onIgnoreTag = options.onIgnoreTag || _default$1.onIgnoreTag;
  options.onIgnoreTagAttr = options.onIgnoreTagAttr || _default$1.onIgnoreTagAttr;
  options.safeAttrValue = options.safeAttrValue || _default$1.safeAttrValue;
  options.escapeHtml = options.escapeHtml || _default$1.escapeHtml;
  this.options = options;

  if (options.css === false) {
    this.cssFilter = false;
  } else {
    options.css = options.css || {};
    this.cssFilter = new FilterCSS$2(options.css);
  }
}

/**
 * start process and returns result
 *
 * @param {String} html
 * @return {String}
 */
FilterXSS.prototype.process = function(html) {
  // compatible with the input
  html = html || "";
  html = html.toString();
  if (!html) return "";

  var me = this;
  var options = me.options;
  var whiteList = options.whiteList;
  var onTag = options.onTag;
  var onIgnoreTag = options.onIgnoreTag;
  var onTagAttr = options.onTagAttr;
  var onIgnoreTagAttr = options.onIgnoreTagAttr;
  var safeAttrValue = options.safeAttrValue;
  var escapeHtml = options.escapeHtml;
  var cssFilter = me.cssFilter;

  // remove invisible characters
  if (options.stripBlankChar) {
    html = _default$1.stripBlankChar(html);
  }

  // remove html comments
  if (!options.allowCommentTag) {
    html = _default$1.stripCommentTag(html);
  }

  // if enable stripIgnoreTagBody
  var stripIgnoreTagBody = false;
  if (options.stripIgnoreTagBody) {
    var stripIgnoreTagBody = _default$1.StripTagBody(
      options.stripIgnoreTagBody,
      onIgnoreTag
    );
    onIgnoreTag = stripIgnoreTagBody.onIgnoreTag;
  }

  var retHtml = parseTag$1(
    html,
    function(sourcePosition, position, tag, html, isClosing) {
      var info = {
        sourcePosition: sourcePosition,
        position: position,
        isClosing: isClosing,
        isWhite: whiteList.hasOwnProperty(tag)
      };

      // call `onTag()`
      var ret = onTag(tag, html, info);
      if (!isNull$1(ret)) return ret;

      if (info.isWhite) {
        if (info.isClosing) {
          return "</" + tag + ">";
        }

        var attrs = getAttrs(html);
        var whiteAttrList = whiteList[tag];
        var attrsHtml = parseAttr$1(attrs.html, function(name, value) {
          // call `onTagAttr()`
          var isWhiteAttr = util$2.indexOf(whiteAttrList, name) !== -1;
          var ret = onTagAttr(tag, name, value, isWhiteAttr);
          if (!isNull$1(ret)) return ret;

          if (isWhiteAttr) {
            // call `safeAttrValue()`
            value = safeAttrValue(tag, name, value, cssFilter);
            if (value) {
              return name + '="' + value + '"';
            } else {
              return name;
            }
          } else {
            // call `onIgnoreTagAttr()`
            var ret = onIgnoreTagAttr(tag, name, value, isWhiteAttr);
            if (!isNull$1(ret)) return ret;
            return;
          }
        });

        // build new tag html
        var html = "<" + tag;
        if (attrsHtml) html += " " + attrsHtml;
        if (attrs.closing) html += " /";
        html += ">";
        return html;
      } else {
        // call `onIgnoreTag()`
        var ret = onIgnoreTag(tag, html, info);
        if (!isNull$1(ret)) return ret;
        return escapeHtml(html);
      }
    },
    escapeHtml
  );

  // if enable stripIgnoreTagBody
  if (stripIgnoreTagBody) {
    retHtml = stripIgnoreTagBody.remove(retHtml);
  }

  return retHtml;
};

var xss = FilterXSS;

var lib$1 = createCommonjsModule(function (module, exports) {
/**
 * xss
 *
 * @author Zongmin Lei<leizongmin@gmail.com>
 */





/**
 * filter xss function
 *
 * @param {String} html
 * @param {Object} options { whiteList, onTag, onTagAttr, onIgnoreTag, onIgnoreTagAttr, safeAttrValue, escapeHtml }
 * @return {String}
 */
function filterXSS(html, options) {
  var xss$1 = new xss(options);
  return xss$1.process(html);
}

exports = module.exports = filterXSS;
exports.filterXSS = filterXSS;
exports.FilterXSS = xss;
for (var i in _default$1) exports[i] = _default$1[i];
for (var i in parser$1) exports[i] = parser$1[i];

// using `xss` on the browser, output `filterXSS` to the globals
if (typeof window !== "undefined") {
  window.filterXSS = module.exports;
}

// using `xss` on the WebWorker, output `filterXSS` to the globals
function isWorkerEnv() {
  return typeof self !== 'undefined' && typeof DedicatedWorkerGlobalScope !== 'undefined' && self instanceof DedicatedWorkerGlobalScope;
}
if (isWorkerEnv()) {
  self.filterXSS = module.exports;
}
});

var propagating = createCommonjsModule(function (module, exports) {
(function (global, factory) {
  module.exports = factory() ;
}(commonjsGlobal, (function () {
  var _firstTarget = null; // singleton, will contain the target element where the touch event started

  /**
   * Extend an Hammer.js instance with event propagation.
   *
   * Features:
   * - Events emitted by hammer will propagate in order from child to parent
   *   elements.
   * - Events are extended with a function `event.stopPropagation()` to stop
   *   propagation to parent elements.
   * - An option `preventDefault` to stop all default browser behavior.
   *
   * Usage:
   *   var hammer = propagatingHammer(new Hammer(element));
   *   var hammer = propagatingHammer(new Hammer(element), {preventDefault: true});
   *
   * @param {Hammer.Manager} hammer   An hammer instance.
   * @param {Object} [options]        Available options:
   *                                  - `preventDefault: true | false | 'mouse' | 'touch' | 'pen'`.
   *                                    Enforce preventing the default browser behavior.
   *                                    Cannot be set to `false`.
   * @return {Hammer.Manager} Returns the same hammer instance with extended
   *                          functionality
   */
  function propagating(hammer, options) {
    var _options = options || {
      preventDefault: false
    };

    if (hammer.Manager) {
      // This looks like the Hammer constructor.
      // Overload the constructors with our own.
      var Hammer = hammer;

      var PropagatingHammer = function(element, options) {
        var o = Object.create(_options);
        if (options) Hammer.assign(o, options);
        return propagating(new Hammer(element, o), o);
      };
      Hammer.assign(PropagatingHammer, Hammer);

      PropagatingHammer.Manager = function (element, options) {
        var o = Object.create(_options);
        if (options) Hammer.assign(o, options);
        return propagating(new Hammer.Manager(element, o), o);
      };

      return PropagatingHammer;
    }

    // create a wrapper object which will override the functions
    // `on`, `off`, `destroy`, and `emit` of the hammer instance
    var wrapper = Object.create(hammer);

    // attach to DOM element
    var element = hammer.element;

    if(!element.hammer) element.hammer = [];
    element.hammer.push(wrapper);

    // register an event to catch the start of a gesture and store the
    // target in a singleton
    hammer.on('hammer.input', function (event) {
      if (_options.preventDefault === true || (_options.preventDefault === event.pointerType)) {
        event.preventDefault();
      }
      if (event.isFirst) {
        _firstTarget = event.target;
      }
    });

    /** @type {Object.<String, Array.<function>>} */
    wrapper._handlers = {};

    /**
     * Register a handler for one or multiple events
     * @param {String} events    A space separated string with events
     * @param {function} handler A callback function, called as handler(event)
     * @returns {Hammer.Manager} Returns the hammer instance
     */
    wrapper.on = function (events, handler) {
      // register the handler
      split(events).forEach(function (event) {
        var _handlers = wrapper._handlers[event];
        if (!_handlers) {
          wrapper._handlers[event] = _handlers = [];

          // register the static, propagated handler
          hammer.on(event, propagatedHandler);
        }
        _handlers.push(handler);
      });

      return wrapper;
    };

    /**
     * Unregister a handler for one or multiple events
     * @param {String} events      A space separated string with events
     * @param {function} [handler] Optional. The registered handler. If not
     *                             provided, all handlers for given events
     *                             are removed.
     * @returns {Hammer.Manager}   Returns the hammer instance
     */
    wrapper.off = function (events, handler) {
      // unregister the handler
      split(events).forEach(function (event) {
        var _handlers = wrapper._handlers[event];
        if (_handlers) {
          _handlers = handler ? _handlers.filter(function (h) {
            return h !== handler;
          }) : [];

          if (_handlers.length > 0) {
            wrapper._handlers[event] = _handlers;
          }
          else {
            // remove static, propagated handler
            hammer.off(event, propagatedHandler);
            delete wrapper._handlers[event];
          }
        }
      });

      return wrapper;
    };

    /**
     * Emit to the event listeners
     * @param {string} eventType
     * @param {Event} event
     */
    wrapper.emit = function(eventType, event) {
      _firstTarget = event.target;
      hammer.emit(eventType, event);
    };

    wrapper.destroy = function () {
      // Detach from DOM element
      var hammers = hammer.element.hammer;
      var idx = hammers.indexOf(wrapper);
      if(idx !== -1) hammers.splice(idx,1);
      if(!hammers.length) delete hammer.element.hammer;

      // clear all handlers
      wrapper._handlers = {};

      // call original hammer destroy
      hammer.destroy();
    };

    // split a string with space separated words
    function split(events) {
      return events.match(/[^ ]+/g);
    }

    /**
     * A static event handler, applying event propagation.
     * @param {Object} event
     */
    function propagatedHandler(event) {
      // let only a single hammer instance handle this event
      if (event.type !== 'hammer.input') {
        // it is possible that the same srcEvent is used with multiple hammer events,
        // we keep track on which events are handled in an object _handled
        if (!event.srcEvent._handled) {
          event.srcEvent._handled = {};
        }

        if (event.srcEvent._handled[event.type]) {
          return;
        }
        else {
          event.srcEvent._handled[event.type] = true;
        }
      }

      // attach a stopPropagation function to the event
      var stopped = false;
      event.stopPropagation = function () {
        stopped = true;
      };

      //wrap the srcEvent's stopPropagation to also stop hammer propagation:
      var srcStop = event.srcEvent.stopPropagation.bind(event.srcEvent);
      if(typeof srcStop == "function") {
        event.srcEvent.stopPropagation = function(){
          srcStop();
          event.stopPropagation();
        };
      }

      // attach firstTarget property to the event
      event.firstTarget = _firstTarget;

      // propagate over all elements (until stopped)
      var elem = _firstTarget;
      while (elem && !stopped) {
        var elemHammer = elem.hammer;
        if(elemHammer){
          var _handlers;
          for(var k = 0; k < elemHammer.length; k++){
            _handlers = elemHammer[k]._handlers[event.type];
            if(_handlers) for (var i = 0; i < _handlers.length && !stopped; i++) {
              _handlers[i](event);
            }
          }
        }
        elem = elem.parentNode;
      }
    }

    return wrapper;
  }

  return propagating;

})));
});

/**
 * Created by Alex on 11/6/2014.
 */
function keycharm(options) {
  var preventDefault = options && options.preventDefault || false;

  var container = options && options.container || window;

  var _exportFunctions = {};
  var _bound = {keydown:{}, keyup:{}};
  var _keys = {};
  var i;

  // a - z
  for (i = 97; i <= 122; i++) {_keys[String.fromCharCode(i)] = {code:65 + (i - 97), shift: false};}
  // A - Z
  for (i = 65; i <= 90; i++) {_keys[String.fromCharCode(i)] = {code:i, shift: true};}
  // 0 - 9
  for (i = 0;  i <= 9;   i++) {_keys['' + i] = {code:48 + i, shift: false};}
  // F1 - F12
  for (i = 1;  i <= 12;   i++) {_keys['F' + i] = {code:111 + i, shift: false};}
  // num0 - num9
  for (i = 0;  i <= 9;   i++) {_keys['num' + i] = {code:96 + i, shift: false};}

  // numpad misc
  _keys['num*'] = {code:106, shift: false};
  _keys['num+'] = {code:107, shift: false};
  _keys['num-'] = {code:109, shift: false};
  _keys['num/'] = {code:111, shift: false};
  _keys['num.'] = {code:110, shift: false};
  // arrows
  _keys['left']  = {code:37, shift: false};
  _keys['up']    = {code:38, shift: false};
  _keys['right'] = {code:39, shift: false};
  _keys['down']  = {code:40, shift: false};
  // extra keys
  _keys['space'] = {code:32, shift: false};
  _keys['enter'] = {code:13, shift: false};
  _keys['shift'] = {code:16, shift: undefined};
  _keys['esc']   = {code:27, shift: false};
  _keys['backspace'] = {code:8, shift: false};
  _keys['tab']       = {code:9, shift: false};
  _keys['ctrl']      = {code:17, shift: false};
  _keys['alt']       = {code:18, shift: false};
  _keys['delete']    = {code:46, shift: false};
  _keys['pageup']    = {code:33, shift: false};
  _keys['pagedown']  = {code:34, shift: false};
  // symbols
  _keys['=']     = {code:187, shift: false};
  _keys['-']     = {code:189, shift: false};
  _keys[']']     = {code:221, shift: false};
  _keys['[']     = {code:219, shift: false};



  var down = function(event) {handleEvent(event,'keydown');};
  var up = function(event) {handleEvent(event,'keyup');};

  // handle the actualy bound key with the event
  var handleEvent = function(event,type) {
    if (_bound[type][event.keyCode] !== undefined) {
      var bound = _bound[type][event.keyCode];
      for (var i = 0; i < bound.length; i++) {
        if (bound[i].shift === undefined) {
          bound[i].fn(event);
        }
        else if (bound[i].shift == true && event.shiftKey == true) {
          bound[i].fn(event);
        }
        else if (bound[i].shift == false && event.shiftKey == false) {
          bound[i].fn(event);
        }
      }

      if (preventDefault == true) {
        event.preventDefault();
      }
    }
  };

  // bind a key to a callback
  _exportFunctions.bind = function(key, callback, type) {
    if (type === undefined) {
      type = 'keydown';
    }
    if (_keys[key] === undefined) {
      throw new Error("unsupported key: " + key);
    }
    if (_bound[type][_keys[key].code] === undefined) {
      _bound[type][_keys[key].code] = [];
    }
    _bound[type][_keys[key].code].push({fn:callback, shift:_keys[key].shift});
  };


  // bind all keys to a call back (demo purposes)
  _exportFunctions.bindAll = function(callback, type) {
    if (type === undefined) {
      type = 'keydown';
    }
    for (var key in _keys) {
      if (_keys.hasOwnProperty(key)) {
        _exportFunctions.bind(key,callback,type);
      }
    }
  };

  // get the key label from an event
  _exportFunctions.getKey = function(event) {
    for (var key in _keys) {
      if (_keys.hasOwnProperty(key)) {
        if (event.shiftKey == true && _keys[key].shift == true && event.keyCode == _keys[key].code) {
          return key;
        }
        else if (event.shiftKey == false && _keys[key].shift == false && event.keyCode == _keys[key].code) {
          return key;
        }
        else if (event.keyCode == _keys[key].code && key == 'shift') {
          return key;
        }
      }
    }
    return "unknown key, currently not supported";
  };

  // unbind either a specific callback from a key or all of them (by leaving callback undefined)
  _exportFunctions.unbind = function(key, callback, type) {
    if (type === undefined) {
      type = 'keydown';
    }
    if (_keys[key] === undefined) {
      throw new Error("unsupported key: " + key);
    }
    if (callback !== undefined) {
      var newBindings = [];
      var bound = _bound[type][_keys[key].code];
      if (bound !== undefined) {
        for (var i = 0; i < bound.length; i++) {
          if (!(bound[i].fn == callback && bound[i].shift == _keys[key].shift)) {
            newBindings.push(_bound[type][_keys[key].code][i]);
          }
        }
      }
      _bound[type][_keys[key].code] = newBindings;
    }
    else {
      _bound[type][_keys[key].code] = [];
    }
  };

  // reset all bound variables.
  _exportFunctions.reset = function() {
    _bound = {keydown:{}, keyup:{}};
  };

  // unbind all listeners and reset all variables.
  _exportFunctions.destroy = function() {
    _bound = {keydown:{}, keyup:{}};
    container.removeEventListener('keydown', down, true);
    container.removeEventListener('keyup', up, true);
  };

  // create listeners.
  container.addEventListener('keydown',down,true);
  container.addEventListener('keyup',up,true);

  // return the public functions.
  return _exportFunctions;
}

/**
 * vis-timeline and vis-graph2d
 * https://visjs.github.io/vis-timeline/
 *
 * Create a fully customizable, interactive timeline with items and ranges.
 *
 * @version 7.4.6
 * @date    2021-01-15T09:00:33.590Z
 *
 * @copyright (c) 2011-2017 Almende B.V, http://almende.com
 * @copyright (c) 2017-2019 visjs contributors, https://github.com/visjs
 *
 * @license
 * vis.js is dual licensed under both
 *
 *   1. The Apache 2.0 License
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *   and
 *
 *   2. The MIT License
 *      http://opensource.org/licenses/MIT
 *
 * vis.js may be distributed under either license.
 */

// first check if moment.js is already loaded in the browser window, if so,
// use this instance. Else, load via commonjs.
//
// Note: This doesn't work in ESM.
var moment$1 = (typeof window !== 'undefined') && window['moment'] || moment;

// utility functions

// parse ASP.Net Date pattern,
// for example '/Date(1198908717056)/' or '/Date(1198908717056-0700)/'
// code from http://momentjs.com/
const ASPDateRegex$1 = /^\/?Date\((-?\d+)/i;
const NumericRegex = /^\d+$/;
/**
 * Convert an object into another type
 *
 * @param object - Value of unknown type.
 * @param type - Name of the desired type.
 *
 * @returns Object in the desired type.
 * @throws Error
 */
function convert(object, type) {
  let match;

  if (object === undefined) {
    return undefined;
  }
  if (object === null) {
    return null;
  }

  if (!type) {
    return object;
  }
  if (!(typeof type === "string") && !(type instanceof String)) {
    throw new Error("Type must be a string");
  }

  //noinspection FallthroughInSwitchStatementJS
  switch (type) {
    case "boolean":
    case "Boolean":
      return Boolean(object);

    case "number":
    case "Number":
      if (isString(object) && !isNaN(Date.parse(object))) {
        return moment(object).valueOf();
      } else {
        // @TODO: I don't think that Number and String constructors are a good idea.
        // This could also fail if the object doesn't have valueOf method or if it's redefined.
        // For example: Object.create(null) or { valueOf: 7 }.
        return Number(object.valueOf());
      }
    case "string":
    case "String":
      return String(object);

    case "Date":
      try {
        return convert(object, "Moment").toDate();
      }
      catch(e){
        if (e instanceof TypeError) {
          throw new TypeError(
            "Cannot convert object of type " + getType(object) + " to type " + type
          );
        } else {
          throw e;
        }
      }

    case "Moment":
      if (isNumber(object)) {
        return moment(object);
      }
      if (object instanceof Date) {
        return moment(object.valueOf());
      } else if (moment.isMoment(object)) {
        return moment(object);
      }
      if (isString(object)) {
        match = ASPDateRegex$1.exec(object);
        if (match) {
          // object is an ASP date
          return moment(Number(match[1])); // parse number
        } 
        match = NumericRegex.exec(object);

        if (match) {
          return moment(Number(object));
        }
        
        return moment(object); // parse string
      } else {
        throw new TypeError(
          "Cannot convert object of type " + getType(object) + " to type " + type
        );
      }

    case "ISODate":
      if (isNumber(object)) {
        return new Date(object);
      } else if (object instanceof Date) {
        return object.toISOString();
      } else if (moment.isMoment(object)) {
        return object.toDate().toISOString();
      } else if (isString(object)) {
        match = ASPDateRegex$1.exec(object);
        if (match) {
          // object is an ASP date
          return new Date(Number(match[1])).toISOString(); // parse number
        } else {
          return moment(object).format(); // ISO 8601
        }
      } else {
        throw new Error(
          "Cannot convert object of type " +
            getType(object) +
            " to type ISODate"
        );
      }

    case "ASPDate":
      if (isNumber(object)) {
        return "/Date(" + object + ")/";
      } else if (object instanceof Date || moment.isMoment(object)) {
        return "/Date(" + object.valueOf() + ")/";
      } else if (isString(object)) {
        match = ASPDateRegex$1.exec(object);
        let value;
        if (match) {
          // object is an ASP date
          value = new Date(Number(match[1])).valueOf(); // parse number
        } else {
          value = new Date(object).valueOf(); // parse string
        }
        return "/Date(" + value + ")/";
      } else {
        throw new Error(
          "Cannot convert object of type " +
            getType(object) +
            " to type ASPDate"
        );
      }

    default:
      throw new Error(`Unknown type ${type}`);
  }
}

/**
 * Create a Data Set like wrapper to seamlessly coerce data types.
 *
 * @param rawDS - The Data Set with raw uncoerced data.
 * @param type - A record assigning a data type to property name.
 *
 * @remarks
 * The write operations (`add`, `remove`, `update` and `updateOnly`) write into
 * the raw (uncoerced) data set. These values are then picked up by a pipe
 * which coerces the values using the [[convert]] function and feeds them into
 * the coerced data set. When querying (`forEach`, `get`, `getIds`, `off` and
 * `on`) the values are then fetched from the coerced data set and already have
 * the required data types. The values are coerced only once when inserted and
 * then the same value is returned each time until it is updated or deleted.
 *
 * For example: `typeCoercedDataSet.add({ id: 7, start: "2020-01-21" })` would
 * result in `typeCoercedDataSet.get(7)` returning `{ id: 7, start: moment(new
 * Date("2020-01-21")).toDate() }`.
 *
 * Use the dispose method prior to throwing a reference to this away. Otherwise
 * the pipe connecting the two Data Sets will keep the unaccessible coerced
 * Data Set alive and updated as long as the raw Data Set exists.
 *
 * @returns A Data Set like object that saves data into the raw Data Set and
 * retrieves them from the coerced Data Set.
 */
function typeCoerceDataSet(
  rawDS,
  type = { start: "Date", end: "Date" }
) {
  const idProp = rawDS._idProp;
  const coercedDS = new DataSet({ fieldId: idProp });

  const pipe = createNewDataPipeFrom(rawDS)
    .map(item =>
      Object.keys(item).reduce((acc, key) => {
        acc[key] = convert(item[key], type[key]);
        return acc;
      }, {})
    )
    .to(coercedDS);

  pipe.all().start();

  return {
    // Write only.
    add: (...args) => rawDS.getDataSet().add(...args),
    remove: (...args) => rawDS.getDataSet().remove(...args),
    update: (...args) => rawDS.getDataSet().update(...args),
    updateOnly: (...args) => rawDS.getDataSet().updateOnly(...args),
    clear : (...args) => rawDS.getDataSet().clear(...args),

    // Read only.
    forEach: coercedDS.forEach.bind(coercedDS),
    get: coercedDS.get.bind(coercedDS),
    getIds: coercedDS.getIds.bind(coercedDS),
    off: coercedDS.off.bind(coercedDS),
    on: coercedDS.on.bind(coercedDS),

    get length() {
      return coercedDS.length;
    },

    // Non standard.
    idProp,
    type,

    rawDS,
    coercedDS,
    dispose: () => pipe.stop()
  };
}

var util$3 = {
  ...util$1,
  convert,
  xss: lib$1
};

/** Prototype for visual components */
class Component {
  /**
 * @param {{dom: Object, domProps: Object, emitter: Emitter, range: Range}} [body]
 * @param {Object} [options]
 */
  constructor(body, options) {  // eslint-disable-line no-unused-vars
    this.options = null;
    this.props = null;
  }

  /**
   * Set options for the component. The new options will be merged into the
   * current options.
   * @param {Object} options
   */
  setOptions(options) {
    if (options) {
      util$3.extend(this.options, options);
    }
  }

  /**
   * Repaint the component
   * @return {boolean} Returns true if the component is resized
   */
  redraw() {
    // should be implemented by the component
    return false;
  }

  /**
   * Destroy the component. Cleanup DOM and event listeners
   */
  destroy() {
    // should be implemented by the component
  }

  /**
   * Test whether the component is resized since the last time _isResized() was
   * called.
   * @return {Boolean} Returns true if the component is resized
   * @protected
   */
  _isResized() {
    const resized = (
      this.props._previousWidth !== this.props.width ||
      this.props._previousHeight !== this.props.height
    );

    this.props._previousWidth = this.props.width;
    this.props._previousHeight = this.props.height;

    return resized;
  }
}

/**
 * used in Core to convert the options into a volatile variable
 * 
 * @param {function} moment
 * @param {Object} body
 * @param {Array | Object} hiddenDates
 * @returns {number}
 */
function convertHiddenOptions(moment, body, hiddenDates) {
  if (hiddenDates && !Array.isArray(hiddenDates)) {
    return convertHiddenOptions(moment, body, [hiddenDates])
  }

  body.hiddenDates = [];
  if (hiddenDates) {
    if (Array.isArray(hiddenDates) == true) {
      for (let i = 0; i < hiddenDates.length; i++) {
        if (hiddenDates[i].repeat === undefined) {
          const dateItem = {};
          dateItem.start = moment(hiddenDates[i].start).toDate().valueOf();
          dateItem.end = moment(hiddenDates[i].end).toDate().valueOf();
          body.hiddenDates.push(dateItem);
        }
      }
      body.hiddenDates.sort((a, b) => a.start - b.start); // sort by start time
    }
  }
}

/**
 * create new entrees for the repeating hidden dates
 *
 * @param {function} moment
 * @param {Object} body
 * @param {Array | Object} hiddenDates
 * @returns {null}
 */
function updateHiddenDates(moment, body, hiddenDates) {
  if (hiddenDates && !Array.isArray(hiddenDates)) {
    return updateHiddenDates(moment, body, [hiddenDates])
  }

  if (hiddenDates && body.domProps.centerContainer.width !== undefined) {
    convertHiddenOptions(moment, body, hiddenDates);

    const start = moment(body.range.start);
    const end = moment(body.range.end);

    const totalRange = (body.range.end - body.range.start);
    const pixelTime = totalRange / body.domProps.centerContainer.width;

    for (let i = 0; i < hiddenDates.length; i++) {
      if (hiddenDates[i].repeat !== undefined) {
        const startDate = moment(hiddenDates[i].start);
        let endDate = moment(hiddenDates[i].end);

        if (startDate._d == "Invalid Date") {
          throw new Error(`Supplied start date is not valid: ${hiddenDates[i].start}`);
        }
        if (endDate._d == "Invalid Date") {
          throw new Error(`Supplied end date is not valid: ${hiddenDates[i].end}`);
        }

        const duration = endDate - startDate;
        if (duration >= 4 * pixelTime) {

          let offset = 0;
          const runUntil = end.clone();
          switch (hiddenDates[i].repeat) {
            case "daily": // case of time
              if (startDate.day() != endDate.day()) {
                offset = 1;
              }
              startDate.dayOfYear(start.dayOfYear());
              startDate.year(start.year());
              startDate.subtract(7,'days');

              endDate.dayOfYear(start.dayOfYear());
              endDate.year(start.year());
              endDate.subtract(7 - offset,'days');

              runUntil.add(1, 'weeks');
              break;
            case "weekly": {
              const dayOffset = endDate.diff(startDate,'days');
              const day = startDate.day();

              // set the start date to the range.start
              startDate.date(start.date());
              startDate.month(start.month());
              startDate.year(start.year());
              endDate = startDate.clone();

              // force
              startDate.day(day);
              endDate.day(day);
              endDate.add(dayOffset,'days');

              startDate.subtract(1,'weeks');
              endDate.subtract(1,'weeks');

              runUntil.add(1, 'weeks');
              break;
            }
            case "monthly":
              if (startDate.month() != endDate.month()) {
                offset = 1;
              }
              startDate.month(start.month());
              startDate.year(start.year());
              startDate.subtract(1,'months');

              endDate.month(start.month());
              endDate.year(start.year());
              endDate.subtract(1,'months');
              endDate.add(offset,'months');

              runUntil.add(1, 'months');
              break;
            case "yearly":
              if (startDate.year() != endDate.year()) {
                offset = 1;
              }
              startDate.year(start.year());
              startDate.subtract(1,'years');
              endDate.year(start.year());
              endDate.subtract(1,'years');
              endDate.add(offset,'years');

              runUntil.add(1, 'years');
              break;
            default:
              console.log("Wrong repeat format, allowed are: daily, weekly, monthly, yearly. Given:", hiddenDates[i].repeat);
              return;
          }
          while (startDate < runUntil) {
            body.hiddenDates.push({start: startDate.valueOf(), end: endDate.valueOf()});
            switch (hiddenDates[i].repeat) {
              case "daily":
                startDate.add(1, 'days');
                endDate.add(1, 'days');
                break;
              case "weekly":
                startDate.add(1, 'weeks');
                endDate.add(1, 'weeks');
                break;
              case "monthly":
                startDate.add(1, 'months');
                endDate.add(1, 'months');
                break;
              case "yearly":
                startDate.add(1, 'y');
                endDate.add(1, 'y');
                break;
              default:
                console.log("Wrong repeat format, allowed are: daily, weekly, monthly, yearly. Given:", hiddenDates[i].repeat);
                return;
            }
          }
          body.hiddenDates.push({start: startDate.valueOf(), end: endDate.valueOf()});
        }
      }
    }
    // remove duplicates, merge where possible
    removeDuplicates(body);
    // ensure the new positions are not on hidden dates
    const startHidden = getIsHidden(body.range.start, body.hiddenDates);
    const endHidden = getIsHidden(body.range.end,body.hiddenDates);
    let rangeStart = body.range.start;
    let rangeEnd = body.range.end;
    if (startHidden.hidden == true) {rangeStart = body.range.startToFront == true ? startHidden.startDate - 1 : startHidden.endDate + 1;}
    if (endHidden.hidden == true)   {rangeEnd   = body.range.endToFront == true ?   endHidden.startDate - 1   : endHidden.endDate + 1;}
    if (startHidden.hidden == true || endHidden.hidden == true) {
      body.range._applyRange(rangeStart, rangeEnd);
    }
  }

}

/**
 * remove duplicates from the hidden dates list. Duplicates are evil. They mess everything up.
 * Scales with N^2
 *
 * @param {Object} body
 */
function removeDuplicates(body) {
  const hiddenDates = body.hiddenDates;
  const safeDates = [];
  for (var i = 0; i < hiddenDates.length; i++) {
    for (let j = 0; j < hiddenDates.length; j++) {
      if (i != j && hiddenDates[j].remove != true && hiddenDates[i].remove != true) {
        // j inside i
        if (hiddenDates[j].start >= hiddenDates[i].start && hiddenDates[j].end <= hiddenDates[i].end) {
          hiddenDates[j].remove = true;
        }
        // j start inside i
        else if (hiddenDates[j].start >= hiddenDates[i].start && hiddenDates[j].start <= hiddenDates[i].end) {
          hiddenDates[i].end = hiddenDates[j].end;
          hiddenDates[j].remove = true;
        }
        // j end inside i
        else if (hiddenDates[j].end >= hiddenDates[i].start && hiddenDates[j].end <= hiddenDates[i].end) {
          hiddenDates[i].start = hiddenDates[j].start;
          hiddenDates[j].remove = true;
        }
      }
    }
  }

  for (i = 0; i < hiddenDates.length; i++) {
    if (hiddenDates[i].remove !== true) {
      safeDates.push(hiddenDates[i]);
    }
  }

  body.hiddenDates = safeDates;
  body.hiddenDates.sort((a, b) => a.start - b.start); // sort by start time
}

/**
 * Used in TimeStep to avoid the hidden times.
 * @param {function} moment
 * @param {TimeStep} timeStep
 * @param {Date} previousTime
 */
function stepOverHiddenDates(moment, timeStep, previousTime) {
  let stepInHidden = false;
  const currentValue = timeStep.current.valueOf();
  for (let i = 0; i < timeStep.hiddenDates.length; i++) {
    const startDate = timeStep.hiddenDates[i].start;
    var endDate = timeStep.hiddenDates[i].end;
    if (currentValue >= startDate && currentValue < endDate) {
      stepInHidden = true;
      break;
    }
  }

  if (stepInHidden == true && currentValue < timeStep._end.valueOf() && currentValue != previousTime) {
    const prevValue = moment(previousTime);
    const newValue = moment(endDate);
    //check if the next step should be major
    if (prevValue.year() != newValue.year()) {timeStep.switchedYear = true;}
    else if (prevValue.month() != newValue.month()) {timeStep.switchedMonth = true;}
    else if (prevValue.dayOfYear() != newValue.dayOfYear()) {timeStep.switchedDay = true;}

    timeStep.current = newValue;
  }
}

///**
// * Used in TimeStep to avoid the hidden times.
// * @param timeStep
// * @param previousTime
// */
//checkFirstStep = function(timeStep) {
//  var stepInHidden = false;
//  var currentValue = timeStep.current.valueOf();
//  for (var i = 0; i < timeStep.hiddenDates.length; i++) {
//    var startDate = timeStep.hiddenDates[i].start;
//    var endDate = timeStep.hiddenDates[i].end;
//    if (currentValue >= startDate && currentValue < endDate) {
//      stepInHidden = true;
//      break;
//    }
//  }
//
//  if (stepInHidden == true && currentValue <= timeStep._end.valueOf()) {
//    var newValue = moment(endDate);
//    timeStep.current = newValue.toDate();
//  }
//};

/**
 * replaces the Core toScreen methods
 *
 * @param {timeline.Core} Core
 * @param {Date} time
 * @param {number} width
 * @returns {number}
 */
function toScreen(Core, time, width) {
  let conversion;
  if (Core.body.hiddenDates.length == 0) {
      conversion = Core.range.conversion(width);
      return (time.valueOf() - conversion.offset) * conversion.scale;
    } else {
      const hidden = getIsHidden(time, Core.body.hiddenDates);
      if (hidden.hidden == true) {
        time = hidden.startDate;
      }

      const duration = getHiddenDurationBetween(Core.body.hiddenDates, Core.range.start, Core.range.end);
      if (time < Core.range.start) {
        conversion = Core.range.conversion(width, duration);
        const hiddenBeforeStart = getHiddenDurationBeforeStart(Core.body.hiddenDates, time, conversion.offset);
        time = Core.options.moment(time).toDate().valueOf();
        time = time + hiddenBeforeStart;
        return -(conversion.offset - time.valueOf()) * conversion.scale;
        
      } else if (time > Core.range.end) {
        const rangeAfterEnd = {start: Core.range.start, end: time};
        time = correctTimeForHidden(Core.options.moment, Core.body.hiddenDates, rangeAfterEnd, time);
        conversion = Core.range.conversion(width, duration);
        return (time.valueOf() - conversion.offset) * conversion.scale;

      } else {
        time = correctTimeForHidden(Core.options.moment, Core.body.hiddenDates, Core.range, time);
        conversion = Core.range.conversion(width, duration);
        return (time.valueOf() - conversion.offset) * conversion.scale;
      }
    }
  }

/**
 * Replaces the core toTime methods
 *
 * @param {timeline.Core} Core
 * @param {number} x
 * @param {number} width
 * @returns {Date}
 */
function toTime(Core, x, width) {
  if (Core.body.hiddenDates.length == 0) {
    const conversion = Core.range.conversion(width);
    return new Date(x / conversion.scale + conversion.offset);
  }
  else {
    const hiddenDuration = getHiddenDurationBetween(Core.body.hiddenDates, Core.range.start, Core.range.end);
    const totalDuration = Core.range.end - Core.range.start - hiddenDuration;
    const partialDuration = totalDuration * x / width;
    const accumulatedHiddenDuration = getAccumulatedHiddenDuration(Core.body.hiddenDates, Core.range, partialDuration);

    return new Date(accumulatedHiddenDuration + partialDuration + Core.range.start);
  }
}

/**
 * Support function
 *
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @param {number} start
 * @param {number} end
 * @returns {number}
 */
function getHiddenDurationBetween(hiddenDates, start, end) {
  let duration = 0;
  for (let i = 0; i < hiddenDates.length; i++) {
    const startDate = hiddenDates[i].start;
    const endDate = hiddenDates[i].end;
    // if time after the cutout, and the
    if (startDate >= start && endDate < end) {
      duration += endDate - startDate;
    }
  }
  return duration;
}

/**
 * Support function
 *
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @param {number} start
 * @param {number} end
 * @returns {number}
 */
function getHiddenDurationBeforeStart(hiddenDates, start, end) {
  let duration = 0;
  for (let i = 0; i < hiddenDates.length; i++) {
    const startDate = hiddenDates[i].start;
    const endDate = hiddenDates[i].end;

    if (startDate >= start && endDate <= end) {
      duration += endDate - startDate;
    }
  }
  return duration;
}

/**
 * Support function
 * @param {function} moment
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @param {{start: number, end: number}} range
 * @param {Date} time
 * @returns {number}
 */
function correctTimeForHidden(moment, hiddenDates, range, time) {
  time = moment(time).toDate().valueOf();
  time -= getHiddenDurationBefore(moment, hiddenDates,range,time);
  return time;
}

/**
 * Support function
 * @param {function} moment
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @param {{start: number, end: number}} range
 * @param {Date} time
 * @returns {number}
 */
function getHiddenDurationBefore(moment, hiddenDates, range, time) {
  let timeOffset = 0;
  time = moment(time).toDate().valueOf();

  for (let i = 0; i < hiddenDates.length; i++) {
    const startDate = hiddenDates[i].start;
    const endDate = hiddenDates[i].end;
    // if time after the cutout, and the
    if (startDate >= range.start && endDate < range.end) {
      if (time >= endDate) {
        timeOffset += (endDate - startDate);
      }
    }
  }
  return timeOffset;
}

/**
 * sum the duration from start to finish, including the hidden duration,
 * until the required amount has been reached, return the accumulated hidden duration
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @param {{start: number, end: number}} range
 * @param {number} [requiredDuration=0]
 * @returns {number}
 */
function getAccumulatedHiddenDuration(hiddenDates, range, requiredDuration) {
  let hiddenDuration = 0;
  let duration = 0;
  let previousPoint = range.start;
  //printDates(hiddenDates)
  for (let i = 0; i < hiddenDates.length; i++) {
    const startDate = hiddenDates[i].start;
    const endDate = hiddenDates[i].end;
    // if time after the cutout, and the
    if (startDate >= range.start && endDate < range.end) {
      duration += startDate - previousPoint;
      previousPoint = endDate;
      if (duration >= requiredDuration) {
        break;
      }
      else {
        hiddenDuration += endDate - startDate;
      }
    }
  }

  return hiddenDuration;
}

/**
 * used to step over to either side of a hidden block. Correction is disabled on tablets, might be set to true
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @param {Date} time
 * @param {number} direction
 * @param {boolean} correctionEnabled
 * @returns {Date|number}
 */
function snapAwayFromHidden(hiddenDates, time, direction, correctionEnabled) {
  const isHidden = getIsHidden(time, hiddenDates);
  if (isHidden.hidden == true) {
    if (direction < 0) {
      if (correctionEnabled == true) {
        return isHidden.startDate - (isHidden.endDate - time) - 1;
      }
      else {
        return isHidden.startDate - 1;
      }
    }
    else {
      if (correctionEnabled == true) {
        return isHidden.endDate + (time - isHidden.startDate) + 1;
      }
      else {
        return isHidden.endDate + 1;
      }
    }
  }
  else {
    return time;
  }

}

/**
 * Check if a time is hidden
 *
 * @param {Date} time
 * @param {Array.<{start: Window.start, end: *}>} hiddenDates
 * @returns {{hidden: boolean, startDate: Window.start, endDate: *}}
 */
function getIsHidden(time, hiddenDates) {
  for (let i = 0; i < hiddenDates.length; i++) {
    var startDate = hiddenDates[i].start;
    var endDate = hiddenDates[i].end;

    if (time >= startDate && time < endDate) { // if the start is entering a hidden zone
      return {hidden: true, startDate, endDate};
    }
  }
  return {hidden: false, startDate, endDate};
}

/**
 * A Range controls a numeric range with a start and end value.
 * The Range adjusts the range based on mouse events or programmatic changes,
 * and triggers events when the range is changing or has been changed.
 */
class Range extends Component {
  /**
 * @param {{dom: Object, domProps: Object, emitter: Emitter}} body
 * @param {Object} [options]    See description at Range.setOptions
 * @constructor Range
 * @extends Component
 */
  constructor(body, options) {
    super();
    const now = moment$1().hours(0).minutes(0).seconds(0).milliseconds(0);
    const start = now.clone().add(-3, 'days').valueOf();
    const end = now.clone().add(3, 'days').valueOf(); 
    this.millisecondsPerPixelCache = undefined;
    
    if(options === undefined) {
      this.start = start;
      this.end = end;
    } else {
      this.start = options.start || start;
      this.end = options.end || end;
    }

    this.rolling = false;

    this.body = body;
    this.deltaDifference = 0;
    this.scaleOffset = 0;
    this.startToFront = false;
    this.endToFront = true;

    // default options
    this.defaultOptions = {
      rtl: false,
      start: null,
      end: null,
      moment: moment$1,
      direction: 'horizontal', // 'horizontal' or 'vertical'
      moveable: true,
      zoomable: true,
      min: null,
      max: null,
      zoomMin: 10,                                // milliseconds
      zoomMax: 1000 * 60 * 60 * 24 * 365 * 10000,  // milliseconds
      rollingMode: {
        follow: false,
        offset: 0.5
      }
    };
    this.options = util$3.extend({}, this.defaultOptions);
    this.props = {
      touch: {}
    };
    this.animationTimer = null;

    // drag listeners for dragging
    this.body.emitter.on('panstart', this._onDragStart.bind(this));
    this.body.emitter.on('panmove',  this._onDrag.bind(this));
    this.body.emitter.on('panend',   this._onDragEnd.bind(this));

    // mouse wheel for zooming
    this.body.emitter.on('mousewheel', this._onMouseWheel.bind(this));

    // pinch to zoom
    this.body.emitter.on('touch', this._onTouch.bind(this));
    this.body.emitter.on('pinch', this._onPinch.bind(this));

    // on click of rolling mode button
    this.body.dom.rollingModeBtn.addEventListener('click', this.startRolling.bind(this));

    this.setOptions(options);
  }

  /**
   * Set options for the range controller
   * @param {Object} options      Available options:
   *                              {number | Date | String} start  Start date for the range
   *                              {number | Date | String} end    End date for the range
   *                              {number} min    Minimum value for start
   *                              {number} max    Maximum value for end
   *                              {number} zoomMin    Set a minimum value for
   *                                                  (end - start).
   *                              {number} zoomMax    Set a maximum value for
   *                                                  (end - start).
   *                              {boolean} moveable Enable moving of the range
   *                                                 by dragging. True by default
   *                              {boolean} zoomable Enable zooming of the range
   *                                                 by pinching/scrolling. True by default
   */
  setOptions(options) {
    if (options) {
      // copy the options that we know
      const fields = [
        'animation', 'direction', 'min', 'max', 'zoomMin', 'zoomMax', 'moveable', 'zoomable',
        'moment', 'activate', 'hiddenDates', 'zoomKey', 'zoomFriction', 'rtl', 'showCurrentTime', 'rollingMode', 'horizontalScroll'
      ];
      util$3.selectiveExtend(fields, this.options, options);

      if (options.rollingMode && options.rollingMode.follow) {
        this.startRolling();
      }
      if ('start' in options || 'end' in options) {
        // apply a new range. both start and end are optional
        this.setRange(options.start, options.end);
      }
    }
  }

  /**
   * Start auto refreshing the current time bar
   */
  startRolling() {
    const me = this;

    /**
     *  Updates the current time.
     */
    function update () {
      me.stopRolling();
      me.rolling = true;


      let interval = me.end - me.start;
      const t = util$3.convert(new Date(), 'Date').valueOf();
      const rollingModeOffset = me.options.rollingMode && me.options.rollingMode.offset || 0.5;

      const start = t - interval * (rollingModeOffset);
      const end = t + interval * (1 - rollingModeOffset);

      const options = {
        animation: false
      };
      me.setRange(start, end, options);

      // determine interval to refresh
      const scale = me.conversion(me.body.domProps.center.width).scale;
      interval = 1 / scale / 10;
      if (interval < 30)   interval = 30;
      if (interval > 1000) interval = 1000;

      me.body.dom.rollingModeBtn.style.visibility = "hidden";
      // start a renderTimer to adjust for the new time
      me.currentTimeTimer = setTimeout(update, interval);
    }

    update();
  }

  /**
   * Stop auto refreshing the current time bar
   */
  stopRolling() {
    if (this.currentTimeTimer !== undefined) {
      clearTimeout(this.currentTimeTimer);
      this.rolling = false;
      this.body.dom.rollingModeBtn.style.visibility = "visible";
    }
  }

  /**
   * Set a new start and end range
   * @param {Date | number | string} start
   * @param {Date | number | string} end
   * @param {Object} options      Available options:
   *                              {boolean | {duration: number, easingFunction: string}} [animation=false]
   *                                    If true, the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   *                              {boolean} [byUser=false]
   *                              {Event}  event  Mouse event
   * @param {Function} callback     a callback function to be executed at the end of this function  
   * @param {Function} frameCallback    a callback function executed each frame of the range animation.
   *                                    The callback will be passed three parameters:
   *                                    {number} easeCoefficient    an easing coefficent
   *                                    {boolean} willDraw          If true the caller will redraw after the callback completes
   *                                    {boolean} done              If true then animation is ending after the current frame
   * @return {void}
   */
  setRange(start, end, options, callback, frameCallback) {
    if (!options) {
      options = {};
    }
    if (options.byUser !== true) {
      options.byUser = false;
    }
    const me = this;
    const finalStart = start != undefined ? util$3.convert(start, 'Date').valueOf() : null;
    const finalEnd   = end != undefined   ? util$3.convert(end, 'Date').valueOf()   : null;
    this._cancelAnimation();
    this.millisecondsPerPixelCache = undefined;

    if (options.animation) { // true or an Object
      const initStart = this.start;
      const initEnd = this.end;
      const duration = (typeof options.animation === 'object' && 'duration' in options.animation) ? options.animation.duration : 500;
      const easingName = (typeof options.animation === 'object' && 'easingFunction' in options.animation) ? options.animation.easingFunction : 'easeInOutQuad';
      const easingFunction = util$3.easingFunctions[easingName];
      if (!easingFunction) {
        throw new Error(`Unknown easing function ${JSON.stringify(easingName)}. Choose from: ${Object.keys(util$3.easingFunctions).join(', ')}`);
      }

      const initTime = Date.now();
      let anyChanged = false;

      const next = () => {
        if (!me.props.touch.dragging) {
          const now = Date.now();
          const time = now - initTime;
          const ease = easingFunction(time / duration);
          const done = time > duration;
          const s = (done || finalStart === null) ? finalStart : initStart + (finalStart - initStart) * ease;
          const e = (done || finalEnd   === null) ? finalEnd   : initEnd   + (finalEnd   - initEnd)   * ease;

          changed = me._applyRange(s, e);
          updateHiddenDates(me.options.moment, me.body, me.options.hiddenDates);
          anyChanged = anyChanged || changed;

          const params = {
            start: new Date(me.start), 
            end: new Date(me.end), 
            byUser: options.byUser,
            event: options.event
          };

          if (frameCallback) { frameCallback(ease, changed, done); }

          if (changed) {          
            me.body.emitter.emit('rangechange', params);
          }

          if (done) {
            if (anyChanged) {
              me.body.emitter.emit('rangechanged', params);
              if (callback) { return callback() }
            }
          }
          else {
            // animate with as high as possible frame rate, leave 20 ms in between
            // each to prevent the browser from blocking
            me.animationTimer = setTimeout(next, 20);
          }
        }
      };

      return next();
    }
    else {
      var changed = this._applyRange(finalStart, finalEnd);
      updateHiddenDates(this.options.moment, this.body, this.options.hiddenDates);
      if (changed) {
        const params = {
          start: new Date(this.start), 
          end: new Date(this.end), 
          byUser: options.byUser, 
          event: options.event
        };

        this.body.emitter.emit('rangechange', params);
        clearTimeout( me.timeoutID );
        me.timeoutID = setTimeout( () => {
          me.body.emitter.emit('rangechanged', params);
        }, 200 );
        if (callback) { return callback() }
      }
    }
  }

  /**
   * Get the number of milliseconds per pixel.
   *
   * @returns {undefined|number}
   */
  getMillisecondsPerPixel() {
    if (this.millisecondsPerPixelCache === undefined) {
      this.millisecondsPerPixelCache = (this.end - this.start) / this.body.dom.center.clientWidth;
    }
    return this.millisecondsPerPixelCache;
  }

  /**
   * Stop an animation
   * @private
   */
  _cancelAnimation() {
    if (this.animationTimer) {
      clearTimeout(this.animationTimer);
      this.animationTimer = null;
    }
  }

  /**
   * Set a new start and end range. This method is the same as setRange, but
   * does not trigger a range change and range changed event, and it returns
   * true when the range is changed
   * @param {number} [start]
   * @param {number} [end]
   * @return {boolean} changed
   * @private
   */
  _applyRange(start, end) {
    let newStart = (start != null) ? util$3.convert(start, 'Date').valueOf() : this.start;
    let newEnd   = (end != null)   ? util$3.convert(end, 'Date').valueOf()   : this.end;
    const max = (this.options.max != null) ? util$3.convert(this.options.max, 'Date').valueOf() : null;
    const min = (this.options.min != null) ? util$3.convert(this.options.min, 'Date').valueOf() : null;
    let diff;

    // check for valid number
    if (isNaN(newStart) || newStart === null) {
      throw new Error(`Invalid start "${start}"`);
    }
    if (isNaN(newEnd) || newEnd === null) {
      throw new Error(`Invalid end "${end}"`);
    }

    // prevent end < start
    if (newEnd < newStart) {
      newEnd = newStart;
    }

    // prevent start < min
    if (min !== null) {
      if (newStart < min) {
        diff = (min - newStart);
        newStart += diff;
        newEnd += diff;

        // prevent end > max
        if (max != null) {
          if (newEnd > max) {
            newEnd = max;
          }
        }
      }
    }

    // prevent end > max
    if (max !== null) {
      if (newEnd > max) {
        diff = (newEnd - max);
        newStart -= diff;
        newEnd -= diff;

        // prevent start < min
        if (min != null) {
          if (newStart < min) {
            newStart = min;
          }
        }
      }
    }

    // prevent (end-start) < zoomMin
    if (this.options.zoomMin !== null) {
      let zoomMin = parseFloat(this.options.zoomMin);
      if (zoomMin < 0) {
        zoomMin = 0;
      }
      if ((newEnd - newStart) < zoomMin) {
        // compensate for a scale of 0.5 ms
        const compensation = 0.5;
        if ((this.end - this.start) === zoomMin && newStart >= this.start - compensation && newEnd <= this.end) {
          // ignore this action, we are already zoomed to the minimum
          newStart = this.start;
          newEnd = this.end;
        }
        else {
          // zoom to the minimum
          diff = (zoomMin - (newEnd - newStart));
          newStart -= diff / 2;
          newEnd += diff / 2;
        }
      }
    }

    // prevent (end-start) > zoomMax
    if (this.options.zoomMax !== null) {
      let zoomMax = parseFloat(this.options.zoomMax);
      if (zoomMax < 0) {
        zoomMax = 0;
      }

      if ((newEnd - newStart) > zoomMax) {
        if ((this.end - this.start) === zoomMax && newStart < this.start && newEnd > this.end) {
          // ignore this action, we are already zoomed to the maximum
          newStart = this.start;
          newEnd = this.end;
        }
        else {
          // zoom to the maximum
          diff = ((newEnd - newStart) - zoomMax);
          newStart += diff / 2;
          newEnd -= diff / 2;
        }
      }
    }

    const changed = (this.start != newStart || this.end != newEnd);

    // if the new range does NOT overlap with the old range, emit checkRangedItems to avoid not showing ranged items (ranged meaning has end time, not necessarily of type Range)
    if (!((newStart >= this.start && newStart   <= this.end) || (newEnd   >= this.start && newEnd   <= this.end)) &&
        !((this.start >= newStart && this.start <= newEnd)   || (this.end >= newStart   && this.end <= newEnd) )) {
      this.body.emitter.emit('checkRangedItems');
    }

    this.start = newStart;
    this.end = newEnd;
    return changed;
  }

  /**
   * Retrieve the current range.
   * @return {Object} An object with start and end properties
   */
  getRange() {
    return {
      start: this.start,
      end: this.end
    };
  }

  /**
   * Calculate the conversion offset and scale for current range, based on
   * the provided width
   * @param {number} width
   * @param {number} [totalHidden=0]
   * @returns {{offset: number, scale: number}} conversion
   */
  conversion(width, totalHidden) {
    return Range.conversion(this.start, this.end, width, totalHidden);
  }

  /**
   * Static method to calculate the conversion offset and scale for a range,
   * based on the provided start, end, and width
   * @param {number} start
   * @param {number} end
   * @param {number} width
   * @param {number} [totalHidden=0]
   * @returns {{offset: number, scale: number}} conversion
   */
  static conversion(start, end, width, totalHidden) {
    if (totalHidden === undefined) {
      totalHidden = 0;
    }
    if (width != 0 && (end - start != 0)) {
      return {
        offset: start,
        scale: width / (end - start - totalHidden)
      }
    }
    else {
      return {
        offset: 0,
        scale: 1
      };
    }
  }

  /**
   * Start dragging horizontally or vertically
   * @param {Event} event
   * @private
   */
  _onDragStart(event) {
    this.deltaDifference = 0;
    this.previousDelta = 0;

    // only allow dragging when configured as movable
    if (!this.options.moveable) return;

    // only start dragging when the mouse is inside the current range
    if (!this._isInsideRange(event)) return;

    // refuse to drag when we where pinching to prevent the timeline make a jump
    // when releasing the fingers in opposite order from the touch screen
    if (!this.props.touch.allowDragging) return;

    this.stopRolling();

    this.props.touch.start = this.start;
    this.props.touch.end = this.end;
    this.props.touch.dragging = true;

    if (this.body.dom.root) {
      this.body.dom.root.style.cursor = 'move';
    }
  }

  /**
   * Perform dragging operation
   * @param {Event} event
   * @private
   */
  _onDrag(event) {
    if (!event) return;

    if (!this.props.touch.dragging) return;

    // only allow dragging when configured as movable
    if (!this.options.moveable) return;

    // TODO: this may be redundant in hammerjs2
    // refuse to drag when we where pinching to prevent the timeline make a jump
    // when releasing the fingers in opposite order from the touch screen
    if (!this.props.touch.allowDragging) return;

    const direction = this.options.direction;
    validateDirection(direction);
    let delta = (direction == 'horizontal') ? event.deltaX : event.deltaY;
    delta -= this.deltaDifference;
    let interval = (this.props.touch.end - this.props.touch.start);

    // normalize dragging speed if cutout is in between.
    const duration = getHiddenDurationBetween(this.body.hiddenDates, this.start, this.end);
    interval -= duration;

    const width = (direction == 'horizontal') ? this.body.domProps.center.width : this.body.domProps.center.height;
    let diffRange;
    if (this.options.rtl) {
      diffRange = delta / width * interval;
    } else {
      diffRange = -delta / width * interval;
    }

    const newStart = this.props.touch.start + diffRange;
    const newEnd = this.props.touch.end + diffRange;

    // snapping times away from hidden zones
    const safeStart = snapAwayFromHidden(this.body.hiddenDates, newStart, this.previousDelta-delta, true);
    const safeEnd = snapAwayFromHidden(this.body.hiddenDates, newEnd, this.previousDelta-delta, true);
    if (safeStart != newStart || safeEnd != newEnd) {
      this.deltaDifference += delta;
      this.props.touch.start = safeStart;
      this.props.touch.end = safeEnd;
      this._onDrag(event);
      return;
    }

    this.previousDelta = delta;
    this._applyRange(newStart, newEnd);


    const startDate = new Date(this.start);
    const endDate = new Date(this.end);

    // fire a rangechange event
    this.body.emitter.emit('rangechange', {
      start: startDate,
      end:   endDate,
      byUser: true,
      event
    });

    // fire a panmove event
    this.body.emitter.emit('panmove');
  }

  /**
   * Stop dragging operation
   * @param {event} event
   * @private
   */
  _onDragEnd(event) {
    if (!this.props.touch.dragging) return;

    // only allow dragging when configured as movable
    if (!this.options.moveable) return;

    // TODO: this may be redundant in hammerjs2
    // refuse to drag when we where pinching to prevent the timeline make a jump
    // when releasing the fingers in opposite order from the touch screen
    if (!this.props.touch.allowDragging) return;

    this.props.touch.dragging = false;
    if (this.body.dom.root) {
      this.body.dom.root.style.cursor = 'auto';
    }

    // fire a rangechanged event
    this.body.emitter.emit('rangechanged', {
      start: new Date(this.start),
      end:   new Date(this.end),
      byUser: true,
      event
    });
  }

  /**
   * Event handler for mouse wheel event, used to zoom
   * Code from http://adomas.org/javascript-mouse-wheel/
   * @param {Event} event
   * @private
   */
  _onMouseWheel(event) {
    // retrieve delta
    let delta = 0;
    if (event.wheelDelta) { /* IE/Opera. */
      delta = event.wheelDelta / 120;
    } else if (event.detail) { /* Mozilla case. */
      // In Mozilla, sign of delta is different than in IE.
      // Also, delta is multiple of 3.
      delta = -event.detail / 3;
    } else if (event.deltaY) {
      delta = -event.deltaY / 3;
    } 

    // don't allow zoom when the according key is pressed and the zoomKey option or not zoomable but movable
    if ((this.options.zoomKey && !event[this.options.zoomKey] && this.options.zoomable) 
      || (!this.options.zoomable && this.options.moveable)) {
      return;
    }

    // only allow zooming when configured as zoomable and moveable
    if (!(this.options.zoomable && this.options.moveable)) return;
    
    // only zoom when the mouse is inside the current range
    if (!this._isInsideRange(event)) return;

    // If delta is nonzero, handle it.
    // Basically, delta is now positive if wheel was scrolled up,
    // and negative, if wheel was scrolled down.
    if (delta) {
      // perform the zoom action. Delta is normally 1 or -1

      // adjust a negative delta such that zooming in with delta 0.1
      // equals zooming out with a delta -0.1

      const zoomFriction = this.options.zoomFriction || 5;
      let scale;
      if (delta < 0) {
        scale = 1 - (delta / zoomFriction);
      }
      else {
        scale = 1 / (1 + (delta / zoomFriction)) ;
      }

      // calculate center, the date to zoom around
      let pointerDate;
      if (this.rolling) {
        const rollingModeOffset = this.options.rollingMode && this.options.rollingMode.offset || 0.5;
        pointerDate = this.start + ((this.end - this.start) * rollingModeOffset);
      } else {
        const pointer = this.getPointer({x: event.clientX, y: event.clientY}, this.body.dom.center);
        pointerDate = this._pointerToDate(pointer);
      }
      this.zoom(scale, pointerDate, delta, event);

      // Prevent default actions caused by mouse wheel
      // (else the page and timeline both scroll)
      event.preventDefault();
    }
  }

  /**
   * Start of a touch gesture
   * @param {Event} event
   * @private
   */
  _onTouch(event) {  // eslint-disable-line no-unused-vars
    this.props.touch.start = this.start;
    this.props.touch.end = this.end;
    this.props.touch.allowDragging = true;
    this.props.touch.center = null;
    this.props.touch.centerDate = null;
    this.scaleOffset = 0;
    this.deltaDifference = 0;
    // Disable the browser default handling of this event.
    util$3.preventDefault(event);
  }

  /**
   * Handle pinch event
   * @param {Event} event
   * @private
   */
  _onPinch(event) {
    // only allow zooming when configured as zoomable and moveable
    if (!(this.options.zoomable && this.options.moveable)) return;

    // Disable the browser default handling of this event.
    util$3.preventDefault(event);

    this.props.touch.allowDragging = false;

    if (!this.props.touch.center) {
      this.props.touch.center = this.getPointer(event.center, this.body.dom.center);
      this.props.touch.centerDate = this._pointerToDate(this.props.touch.center);
    }

    this.stopRolling();
    const scale = 1 / (event.scale + this.scaleOffset);
    const centerDate = this.props.touch.centerDate;

    const hiddenDuration = getHiddenDurationBetween(this.body.hiddenDates, this.start, this.end);
    const hiddenDurationBefore = getHiddenDurationBefore(this.options.moment, this.body.hiddenDates, this, centerDate);
    const hiddenDurationAfter = hiddenDuration - hiddenDurationBefore;

    // calculate new start and end
    let newStart = (centerDate - hiddenDurationBefore) + (this.props.touch.start - (centerDate - hiddenDurationBefore)) * scale;
    let newEnd = (centerDate + hiddenDurationAfter) + (this.props.touch.end - (centerDate + hiddenDurationAfter)) * scale;

    // snapping times away from hidden zones
    this.startToFront = 1 - scale <= 0; // used to do the right auto correction with periodic hidden times
    this.endToFront = scale - 1 <= 0;   // used to do the right auto correction with periodic hidden times
    
    const safeStart = snapAwayFromHidden(this.body.hiddenDates, newStart, 1 - scale, true);
    const safeEnd = snapAwayFromHidden(this.body.hiddenDates, newEnd, scale - 1, true);
    if (safeStart != newStart || safeEnd != newEnd) {
      this.props.touch.start = safeStart;
      this.props.touch.end = safeEnd;
      this.scaleOffset = 1 - event.scale;
      newStart = safeStart;
      newEnd = safeEnd;
    }
    
    const options = {
      animation: false,
      byUser: true,
      event
    };
    this.setRange(newStart, newEnd, options);

    this.startToFront = false; // revert to default
    this.endToFront = true; // revert to default
  }

  /**
   * Test whether the mouse from a mouse event is inside the visible window,
   * between the current start and end date
   * @param {Object} event
   * @return {boolean} Returns true when inside the visible window
   * @private
   */
  _isInsideRange(event) {
    // calculate the time where the mouse is, check whether inside
    // and no scroll action should happen.
    const clientX = event.center ? event.center.x : event.clientX;
    const centerContainerRect = this.body.dom.centerContainer.getBoundingClientRect();
    const x = this.options.rtl ? clientX - centerContainerRect.left : centerContainerRect.right - clientX;
    const time = this.body.util.toTime(x);

    return time >= this.start && time <= this.end;
  }

  /**
   * Helper function to calculate the center date for zooming
   * @param {{x: number, y: number}} pointer
   * @return {number} date
   * @private
   */
  _pointerToDate(pointer) {
    let conversion;
    const direction = this.options.direction;

    validateDirection(direction);

    if (direction == 'horizontal') {
      return this.body.util.toTime(pointer.x).valueOf();
    }
    else {
      const height = this.body.domProps.center.height;
      conversion = this.conversion(height);
      return pointer.y / conversion.scale + conversion.offset;
    }
  }

  /**
   * Get the pointer location relative to the location of the dom element
   * @param {{x: number, y: number}} touch
   * @param {Element} element   HTML DOM element
   * @return {{x: number, y: number}} pointer
   * @private
   */
  getPointer(touch, element) {
    const elementRect = element.getBoundingClientRect();
    if (this.options.rtl) {
      return {
        x: elementRect.right - touch.x,
        y: touch.y - elementRect.top
      };
    } else {
      return {
        x: touch.x - elementRect.left,
        y: touch.y - elementRect.top
      };
    }
  }

  /**
   * Zoom the range the given scale in or out. Start and end date will
   * be adjusted, and the timeline will be redrawn. You can optionally give a
   * date around which to zoom.
   * For example, try scale = 0.9 or 1.1
   * @param {number} scale      Scaling factor. Values above 1 will zoom out,
   *                            values below 1 will zoom in.
   * @param {number} [center]   Value representing a date around which will
   *                            be zoomed.
   * @param {number} delta
   * @param {Event} event
   */
  zoom(scale, center, delta, event) {
    // if centerDate is not provided, take it half between start Date and end Date
    if (center == null) {
      center = (this.start + this.end) / 2;
    }

    const hiddenDuration = getHiddenDurationBetween(this.body.hiddenDates, this.start, this.end);
    const hiddenDurationBefore = getHiddenDurationBefore(this.options.moment, this.body.hiddenDates, this, center);
    const hiddenDurationAfter = hiddenDuration - hiddenDurationBefore;

    // calculate new start and end
    let newStart = (center-hiddenDurationBefore) + (this.start - (center-hiddenDurationBefore)) * scale;
    let newEnd   = (center+hiddenDurationAfter) + (this.end - (center+hiddenDurationAfter)) * scale;

    // snapping times away from hidden zones
    this.startToFront = delta > 0 ? false : true; // used to do the right autocorrection with periodic hidden times
    this.endToFront = -delta  > 0 ? false : true; // used to do the right autocorrection with periodic hidden times
    const safeStart = snapAwayFromHidden(this.body.hiddenDates, newStart, delta, true);
    const safeEnd = snapAwayFromHidden(this.body.hiddenDates, newEnd, -delta, true);
    if (safeStart != newStart || safeEnd != newEnd) {
      newStart = safeStart;
      newEnd = safeEnd;
    }

    const options = {
      animation: false,
      byUser: true,
      event
    };
    this.setRange(newStart, newEnd, options);

    this.startToFront = false; // revert to default
    this.endToFront = true; // revert to default
  }

  /**
   * Move the range with a given delta to the left or right. Start and end
   * value will be adjusted. For example, try delta = 0.1 or -0.1
   * @param {number}  delta     Moving amount. Positive value will move right,
   *                            negative value will move left
   */
  move(delta) {
    // zoom start Date and end Date relative to the centerDate
    const diff = (this.end - this.start);

    // apply new values
    const newStart = this.start + diff * delta;
    const newEnd = this.end + diff * delta;

    // TODO: reckon with min and max range

    this.start = newStart;
    this.end = newEnd;
  }

  /**
   * Move the range to a new center point
   * @param {number} moveTo      New center point of the range
   */
  moveTo(moveTo) {
    const center = (this.start + this.end) / 2;

    const diff = center - moveTo;

    // calculate new start and end
    const newStart = this.start - diff;
    const newEnd = this.end - diff;

    const options = {
      animation: false,
      byUser: true,
      event: null
    };
    this.setRange(newStart, newEnd, options);
  }
}

/**
 * Test whether direction has a valid value
 * @param {string} direction    'horizontal' or 'vertical'
 */
function validateDirection (direction) {
  if (direction != 'horizontal' && direction != 'vertical') {
    throw new TypeError(`Unknown direction "${direction}". Choose "horizontal" or "vertical".`);
  }
}

/**
 * Setup a mock hammer.js object, for unit testing.
 *
 * Inspiration: https://github.com/uber/deck.gl/pull/658
 *
 * @returns {{on: noop, off: noop, destroy: noop, emit: noop, get: get}}
 */
function hammerMock$1() {
  const noop = () => {};

  return {
    on: noop,
    off: noop,
    destroy: noop,
    emit: noop,

    get(m) {	//eslint-disable-line no-unused-vars
      return {
        set: noop
      };
    }
  };
}

let modifiedHammer;

if (typeof window !== 'undefined') {
  const OurHammer = window['Hammer'] || Hammer;
  modifiedHammer = propagating(OurHammer, {
    preventDefault: 'mouse'
  });
} else {
  modifiedHammer = () => // hammer.js is only available in a browser, not in node.js. Replacing it with a mock object.
  hammerMock$1();
}

var Hammer$2 = modifiedHammer;

/**
 * Register a touch event, taking place before a gesture
 * @param {Hammer} hammer       A hammer instance
 * @param {function} callback   Callback, called as callback(event)
 */
function onTouch (hammer, callback) {
  callback.inputHandler = function (event) {
    if (event.isFirst) {
      callback(event);
    }
  };

  hammer.on('hammer.input', callback.inputHandler);
}

/**
 * Register a release event, taking place after a gesture
 * @param {Hammer} hammer       A hammer instance
 * @param {function} callback   Callback, called as callback(event)
 * @returns {*}
 */
function onRelease (hammer, callback) {
  callback.inputHandler = function (event) {
    if (event.isFinal) {
      callback(event);
    }
  };

  return hammer.on('hammer.input', callback.inputHandler);
}

/**
 * Hack the PinchRecognizer such that it doesn't prevent default behavior
 * for vertical panning.
 *
 * Yeah ... this is quite a hack ... see https://github.com/hammerjs/hammer.js/issues/932
 *
 * @param {Hammer.Pinch} pinchRecognizer
 * @return {Hammer.Pinch} returns the pinchRecognizer
 */
function disablePreventDefaultVertically (pinchRecognizer) {
  const TOUCH_ACTION_PAN_Y = 'pan-y';

  pinchRecognizer.getTouchAction = function() {
    // default method returns [TOUCH_ACTION_NONE]
    return [TOUCH_ACTION_PAN_Y];
  };

  return pinchRecognizer;
}

/**
 * The class TimeStep is an iterator for dates. You provide a start date and an
 * end date. The class itself determines the best scale (step size) based on the
 * provided start Date, end Date, and minimumStep.
 *
 * If minimumStep is provided, the step size is chosen as close as possible
 * to the minimumStep but larger than minimumStep. If minimumStep is not
 * provided, the scale is set to 1 DAY.
 * The minimumStep should correspond with the onscreen size of about 6 characters
 *
 * Alternatively, you can set a scale by hand.
 * After creation, you can initialize the class by executing first(). Then you
 * can iterate from the start date to the end date via next(). You can check if
 * the end date is reached with the function hasNext(). After each step, you can
 * retrieve the current date via getCurrent().
 * The TimeStep has scales ranging from milliseconds, seconds, minutes, hours,
 * days, to years.
 *
 * Version: 1.2
 *
 */
class TimeStep {
  /**
    * @param {Date} [start]         The start date, for example new Date(2010, 9, 21)
    *                               or new Date(2010, 9, 21, 23, 45, 00)
    * @param {Date} [end]           The end date
    * @param {number} [minimumStep] Optional. Minimum step size in milliseconds
    * @param {Date|Array.<Date>} [hiddenDates] Optional.
    * @param {{showMajorLabels: boolean, showWeekScale: boolean}} [options] Optional.
    * @constructor  TimeStep
    */
  constructor(start, end, minimumStep, hiddenDates, options) {
    this.moment = (options && options.moment) || moment$1;
    this.options = options ? options : {};

    // variables
    this.current = this.moment();
    this._start = this.moment();
    this._end = this.moment();

    this.autoScale  = true;
    this.scale = 'day';
    this.step = 1;

    // initialize the range
    this.setRange(start, end, minimumStep);

    // hidden Dates options
    this.switchedDay = false;
    this.switchedMonth = false;
    this.switchedYear = false;
    if (Array.isArray(hiddenDates)) {
      this.hiddenDates = hiddenDates;
    }
    else if (hiddenDates != undefined) {
      this.hiddenDates = [hiddenDates];
    }
    else {
      this.hiddenDates = [];
    }

    this.format = TimeStep.FORMAT; // default formatting
  }

  /**
   * Set custom constructor function for moment. Can be used to set dates
   * to UTC or to set a utcOffset.
   * @param {function} moment
   */
  setMoment(moment) {
    this.moment = moment;

    // update the date properties, can have a new utcOffset
    this.current = this.moment(this.current.valueOf());
    this._start = this.moment(this._start.valueOf());
    this._end = this.moment(this._end.valueOf());
  }

  /**
   * Set custom formatting for the minor an major labels of the TimeStep.
   * Both `minorLabels` and `majorLabels` are an Object with properties:
   * 'millisecond', 'second', 'minute', 'hour', 'weekday', 'day', 'week', 'month', 'year'.
   * @param {{minorLabels: Object, majorLabels: Object}} format
   */
  setFormat(format) {
    const defaultFormat = util$3.deepExtend({}, TimeStep.FORMAT);
    this.format = util$3.deepExtend(defaultFormat, format);
  }

  /**
   * Set a new range
   * If minimumStep is provided, the step size is chosen as close as possible
   * to the minimumStep but larger than minimumStep. If minimumStep is not
   * provided, the scale is set to 1 DAY.
   * The minimumStep should correspond with the onscreen size of about 6 characters
   * @param {Date} [start]      The start date and time.
   * @param {Date} [end]        The end date and time.
   * @param {int} [minimumStep] Optional. Minimum step size in milliseconds
   */
  setRange(start, end, minimumStep) {
    if (!(start instanceof Date) || !(end instanceof Date)) {
      throw  "No legal start or end date in method setRange";
    }

    this._start = (start != undefined) ? this.moment(start.valueOf()) : Date.now();
    this._end = (end != undefined) ? this.moment(end.valueOf()) : Date.now();

    if (this.autoScale) {
      this.setMinimumStep(minimumStep);
    }
  }

  /**
   * Set the range iterator to the start date.
   */
  start() {
    this.current = this._start.clone();
    this.roundToMinor();
  }

  /**
   * Round the current date to the first minor date value
   * This must be executed once when the current date is set to start Date
   */
  roundToMinor() {
    // round to floor
    // to prevent year & month scales rounding down to the first day of week we perform this separately
    if (this.scale == 'week') {
      this.current.weekday(0);
    }
    // IMPORTANT: we have no breaks in this switch! (this is no bug)
    // noinspection FallThroughInSwitchStatementJS
    switch (this.scale) {
      case 'year':
        this.current.year(this.step * Math.floor(this.current.year() / this.step));
        this.current.month(0);
      case 'month':        this.current.date(1);          // eslint-disable-line no-fallthrough
      case 'week':                                        // eslint-disable-line no-fallthrough
      case 'day':                                         // eslint-disable-line no-fallthrough
      case 'weekday':      this.current.hours(0);         // eslint-disable-line no-fallthrough
      case 'hour':         this.current.minutes(0);       // eslint-disable-line no-fallthrough
      case 'minute':       this.current.seconds(0);       // eslint-disable-line no-fallthrough
      case 'second':       this.current.milliseconds(0);  // eslint-disable-line no-fallthrough
      //case 'millisecond': // nothing to do for milliseconds
    }

    if (this.step != 1) {
      // round down to the first minor value that is a multiple of the current step size
      let  priorCurrent = this.current.clone();
      switch (this.scale) {        
        case 'millisecond':  this.current.subtract(this.current.milliseconds() % this.step, 'milliseconds');  break;
        case 'second':       this.current.subtract(this.current.seconds() % this.step, 'seconds'); break;
        case 'minute':       this.current.subtract(this.current.minutes() % this.step, 'minutes'); break;
        case 'hour':         this.current.subtract(this.current.hours() % this.step, 'hours'); break;
        case 'weekday':      // intentional fall through
        case 'day':          this.current.subtract((this.current.date() - 1) % this.step, 'day'); break;
        case 'week':         this.current.subtract(this.current.week() % this.step, 'week'); break;
        case 'month':        this.current.subtract(this.current.month() % this.step, 'month');  break;
        case 'year':         this.current.subtract(this.current.year() % this.step, 'year'); break;
      }
      if (!priorCurrent.isSame(this.current)) {
          this.current = this.moment(snapAwayFromHidden(this.hiddenDates, this.current.valueOf(), -1, true));
      }
    }
  }

  /**
   * Check if the there is a next step
   * @return {boolean}  true if the current date has not passed the end date
   */
  hasNext() {
    return (this.current.valueOf() <= this._end.valueOf());
  }

  /**
   * Do the next step
   */
  next() {
    const prev = this.current.valueOf();

    // Two cases, needed to prevent issues with switching daylight savings
    // (end of March and end of October)
    switch (this.scale) {
      case 'millisecond':  this.current.add(this.step, 'millisecond'); break;
      case 'second':       this.current.add(this.step, 'second'); break;
      case 'minute':       this.current.add(this.step, 'minute'); break;
      case 'hour':
        this.current.add(this.step, 'hour');

        if (this.current.month() < 6) {
          this.current.subtract(this.current.hours() % this.step, 'hour');
        } else {
          if (this.current.hours() % this.step !== 0) {
            this.current.add(this.step - this.current.hours() % this.step, 'hour');
          }
        }
        break;
      case 'weekday':      // intentional fall through
      case 'day':          this.current.add(this.step, 'day'); break;
      case 'week':
        if (this.current.weekday() !== 0){ // we had a month break not correlating with a week's start before
          this.current.weekday(0); // switch back to week cycles
          this.current.add(this.step, 'week');
        } else if(this.options.showMajorLabels === false) {
          this.current.add(this.step, 'week'); // the default case
        } else { // first day of the week
          const nextWeek = this.current.clone();
          nextWeek.add(1, 'week');
          if(nextWeek.isSame(this.current, 'month')){ // is the first day of the next week in the same month?
            this.current.add(this.step, 'week'); // the default case
          } else { // inject a step at each first day of the month
            this.current.add(this.step, 'week');
            this.current.date(1);
          }
        }
        break;
      case 'month':        this.current.add(this.step, 'month'); break;
      case 'year':         this.current.add(this.step, 'year'); break;
    }

    if (this.step != 1) {
      // round down to the correct major value
      switch (this.scale) {
        case 'millisecond':  if(this.current.milliseconds() > 0 && this.current.milliseconds() < this.step) this.current.milliseconds(0);  break;
        case 'second':       if(this.current.seconds() > 0 && this.current.seconds() < this.step) this.current.seconds(0);  break;
        case 'minute':       if(this.current.minutes() > 0 && this.current.minutes() < this.step) this.current.minutes(0); break;
        case 'hour':         if(this.current.hours() > 0 && this.current.hours() < this.step) this.current.hours(0);  break;
        case 'weekday':      // intentional fall through
        case 'day':          if(this.current.date() < this.step+1) this.current.date(1); break;
        case 'week':         if(this.current.week() < this.step) this.current.week(1); break; // week numbering starts at 1, not 0
        case 'month':        if(this.current.month() < this.step) this.current.month(0);  break;
      }
    }

    // safety mechanism: if current time is still unchanged, move to the end
    if (this.current.valueOf() == prev) {
      this.current = this._end.clone();
    }

    // Reset switches for year, month and day. Will get set to true where appropriate in DateUtil.stepOverHiddenDates
    this.switchedDay = false;
    this.switchedMonth = false;
    this.switchedYear = false;

    stepOverHiddenDates(this.moment, this, prev);
  }

  /**
   * Get the current datetime
   * @return {Moment}  current The current date
   */
  getCurrent() {
    return this.current.clone();
  }

  /**
   * Set a custom scale. Autoscaling will be disabled.
   * For example setScale('minute', 5) will result
   * in minor steps of 5 minutes, and major steps of an hour.
   *
   * @param {{scale: string, step: number}} params
   *                               An object containing two properties:
   *                               - A string 'scale'. Choose from 'millisecond', 'second',
   *                                 'minute', 'hour', 'weekday', 'day', 'week', 'month', 'year'.
   *                               - A number 'step'. A step size, by default 1.
   *                                 Choose for example 1, 2, 5, or 10.
   */
  setScale(params) {
    if (params && typeof params.scale == 'string') {
      this.scale = params.scale;
      this.step = params.step > 0 ? params.step : 1;
      this.autoScale = false;
    }
  }

  /**
   * Enable or disable autoscaling
   * @param {boolean} enable  If true, autoascaling is set true
   */
  setAutoScale(enable) {
    this.autoScale = enable;
  }

  /**
   * Automatically determine the scale that bests fits the provided minimum step
   * @param {number} [minimumStep]  The minimum step size in milliseconds
   */
  setMinimumStep(minimumStep) {
    if (minimumStep == undefined) {
      return;
    }

    //var b = asc + ds;

    const stepYear       = (1000 * 60 * 60 * 24 * 30 * 12);
    const stepMonth      = (1000 * 60 * 60 * 24 * 30);
    const stepDay        = (1000 * 60 * 60 * 24);
    const stepHour       = (1000 * 60 * 60);
    const stepMinute     = (1000 * 60);
    const stepSecond     = (1000);
    const stepMillisecond= (1);

    // find the smallest step that is larger than the provided minimumStep
    if (stepYear*1000 > minimumStep)        {this.scale = 'year';        this.step = 1000;}
    if (stepYear*500 > minimumStep)         {this.scale = 'year';        this.step = 500;}
    if (stepYear*100 > minimumStep)         {this.scale = 'year';        this.step = 100;}
    if (stepYear*50 > minimumStep)          {this.scale = 'year';        this.step = 50;}
    if (stepYear*10 > minimumStep)          {this.scale = 'year';        this.step = 10;}
    if (stepYear*5 > minimumStep)           {this.scale = 'year';        this.step = 5;}
    if (stepYear > minimumStep)             {this.scale = 'year';        this.step = 1;}
    if (stepMonth*3 > minimumStep)          {this.scale = 'month';       this.step = 3;}
    if (stepMonth > minimumStep)            {this.scale = 'month';       this.step = 1;}
    if (stepDay*7 > minimumStep && this.options.showWeekScale)            {this.scale = 'week';        this.step = 1;}
    if (stepDay*2 > minimumStep)            {this.scale = 'day';         this.step = 2;}
    if (stepDay > minimumStep)              {this.scale = 'day';         this.step = 1;}
    if (stepDay/2 > minimumStep)            {this.scale = 'weekday';     this.step = 1;}
    if (stepHour*4 > minimumStep)           {this.scale = 'hour';        this.step = 4;}
    if (stepHour > minimumStep)             {this.scale = 'hour';        this.step = 1;}
    if (stepMinute*15 > minimumStep)        {this.scale = 'minute';      this.step = 15;}
    if (stepMinute*10 > minimumStep)        {this.scale = 'minute';      this.step = 10;}
    if (stepMinute*5 > minimumStep)         {this.scale = 'minute';      this.step = 5;}
    if (stepMinute > minimumStep)           {this.scale = 'minute';      this.step = 1;}
    if (stepSecond*15 > minimumStep)        {this.scale = 'second';      this.step = 15;}
    if (stepSecond*10 > minimumStep)        {this.scale = 'second';      this.step = 10;}
    if (stepSecond*5 > minimumStep)         {this.scale = 'second';      this.step = 5;}
    if (stepSecond > minimumStep)           {this.scale = 'second';      this.step = 1;}
    if (stepMillisecond*200 > minimumStep)  {this.scale = 'millisecond'; this.step = 200;}
    if (stepMillisecond*100 > minimumStep)  {this.scale = 'millisecond'; this.step = 100;}
    if (stepMillisecond*50 > minimumStep)   {this.scale = 'millisecond'; this.step = 50;}
    if (stepMillisecond*10 > minimumStep)   {this.scale = 'millisecond'; this.step = 10;}
    if (stepMillisecond*5 > minimumStep)    {this.scale = 'millisecond'; this.step = 5;}
    if (stepMillisecond > minimumStep)      {this.scale = 'millisecond'; this.step = 1;}
  }

  /**
   * Snap a date to a rounded value.
   * The snap intervals are dependent on the current scale and step.
   * Static function
   * @param {Date} date    the date to be snapped.
   * @param {string} scale Current scale, can be 'millisecond', 'second',
   *                       'minute', 'hour', 'weekday, 'day', 'week', 'month', 'year'.
   * @param {number} step  Current step (1, 2, 4, 5, ...
   * @return {Date} snappedDate
   */
  static snap(date, scale, step) {
    const clone = moment$1(date);

    if (scale == 'year') {
      const year = clone.year() + Math.round(clone.month() / 12);
      clone.year(Math.round(year / step) * step);
      clone.month(0);
      clone.date(0);
      clone.hours(0);
      clone.minutes(0);
      clone.seconds(0);
      clone.milliseconds(0);
    }
    else if (scale == 'month') {
      if (clone.date() > 15) {
        clone.date(1);
        clone.add(1, 'month');
        // important: first set Date to 1, after that change the month.
      }
      else {
        clone.date(1);
      }

      clone.hours(0);
      clone.minutes(0);
      clone.seconds(0);
      clone.milliseconds(0);
    }
    else if (scale == 'week') {
        if (clone.weekday() > 2) { // doing it the momentjs locale aware way
            clone.weekday(0);
            clone.add(1, 'week');
        }
        else {
            clone.weekday(0);
        }

        clone.hours(0);
        clone.minutes(0);
        clone.seconds(0);
        clone.milliseconds(0);
    }
    else if (scale == 'day') {
      //noinspection FallthroughInSwitchStatementJS
      switch (step) {
        case 5:
        case 2:
          clone.hours(Math.round(clone.hours() / 24) * 24); break;
        default:
          clone.hours(Math.round(clone.hours() / 12) * 12); break;
      }
      clone.minutes(0);
      clone.seconds(0);
      clone.milliseconds(0);
    }
    else if (scale == 'weekday') {
      //noinspection FallthroughInSwitchStatementJS
      switch (step) {
        case 5:
        case 2:
          clone.hours(Math.round(clone.hours() / 12) * 12); break;
        default:
          clone.hours(Math.round(clone.hours() / 6) * 6); break;
      }
      clone.minutes(0);
      clone.seconds(0);
      clone.milliseconds(0);
    }
    else if (scale == 'hour') {
      switch (step) {
        case 4:
          clone.minutes(Math.round(clone.minutes() / 60) * 60); break;
        default:
          clone.minutes(Math.round(clone.minutes() / 30) * 30); break;
      }
      clone.seconds(0);
      clone.milliseconds(0);
    } else if (scale == 'minute') {
      //noinspection FallthroughInSwitchStatementJS
      switch (step) {
        case 15:
        case 10:
          clone.minutes(Math.round(clone.minutes() / 5) * 5);
          clone.seconds(0);
          break;
        case 5:
          clone.seconds(Math.round(clone.seconds() / 60) * 60); break;
        default:
          clone.seconds(Math.round(clone.seconds() / 30) * 30); break;
      }
      clone.milliseconds(0);
    }
    else if (scale == 'second') {
      //noinspection FallthroughInSwitchStatementJS
      switch (step) {
        case 15:
        case 10:
          clone.seconds(Math.round(clone.seconds() / 5) * 5);
          clone.milliseconds(0);
          break;
        case 5:
          clone.milliseconds(Math.round(clone.milliseconds() / 1000) * 1000); break;
        default:
          clone.milliseconds(Math.round(clone.milliseconds() / 500) * 500); break;
      }
    }
    else if (scale == 'millisecond') {
      const _step = step > 5 ? step / 2 : 1;
      clone.milliseconds(Math.round(clone.milliseconds() / _step) * _step);
    }

    return clone;
  }

  /**
   * Check if the current value is a major value (for example when the step
   * is DAY, a major value is each first day of the MONTH)
   * @return {boolean} true if current date is major, else false.
   */
  isMajor() {
    if (this.switchedYear == true) {
      switch (this.scale) {
        case 'year':
        case 'month':
        case 'week':
        case 'weekday':
        case 'day':
        case 'hour':
        case 'minute':
        case 'second':
        case 'millisecond':
          return true;
        default:
          return false;
      }
    }
    else if (this.switchedMonth == true) {
      switch (this.scale) {
        case 'week':
        case 'weekday':
        case 'day':
        case 'hour':
        case 'minute':
        case 'second':
        case 'millisecond':
          return true;
        default:
          return false;
      }
    }
    else if (this.switchedDay == true) {
      switch (this.scale) {
        case 'millisecond':
        case 'second':
        case 'minute':
        case 'hour':
          return true;
        default:
          return false;
      }
    }

    const date = this.moment(this.current);
    switch (this.scale) {
      case 'millisecond':
        return (date.milliseconds() == 0);
      case 'second':
        return (date.seconds() == 0);
      case 'minute':
        return (date.hours() == 0) && (date.minutes() == 0);
      case 'hour':
        return (date.hours() == 0);
      case 'weekday': // intentional fall through
      case 'day':
        return (date.date() == 1);
      case 'week':
        return (date.date() == 1);
      case 'month':
        return (date.month() == 0);
      case 'year':
        return false;
      default:
        return false;
    }
  }

  /**
   * Returns formatted text for the minor axislabel, depending on the current
   * date and the scale. For example when scale is MINUTE, the current time is
   * formatted as "hh:mm".
   * @param {Date} [date=this.current] custom date. if not provided, current date is taken
   * @returns {String}
   */
  getLabelMinor(date) {
    if (date == undefined) {
      date = this.current;
    }
    if (date instanceof Date) {
      date = this.moment(date);
    }

    if (typeof(this.format.minorLabels) === "function") {
      return this.format.minorLabels(date, this.scale, this.step);
    }

    const format = this.format.minorLabels[this.scale];
    // noinspection FallThroughInSwitchStatementJS
    switch (this.scale) {
      case 'week':
        // Don't draw the minor label if this date is the first day of a month AND if it's NOT the start of the week.
        // The 'date' variable may actually be the 'next' step when called from TimeAxis' _repaintLabels.
        if(date.date() === 1 && date.weekday() !== 0){
            return "";
        }
      default: // eslint-disable-line no-fallthrough
        return (format && format.length > 0) ? this.moment(date).format(format) : '';
    }
  }

  /**
   * Returns formatted text for the major axis label, depending on the current
   * date and the scale. For example when scale is MINUTE, the major scale is
   * hours, and the hour will be formatted as "hh".
   * @param {Date} [date=this.current] custom date. if not provided, current date is taken
   * @returns {String}
   */
  getLabelMajor(date) {
    if (date == undefined) {
      date = this.current;
    }
    if (date instanceof Date) {
      date = this.moment(date);
    }

    if (typeof(this.format.majorLabels) === "function") {
      return this.format.majorLabels(date, this.scale, this.step);
    }

    const format = this.format.majorLabels[this.scale];
    return (format && format.length > 0) ? this.moment(date).format(format) : '';
  }

  /**
   * get class name
   * @return {string} class name
   */
  getClassName() {
    const _moment = this.moment;
    const m = this.moment(this.current);
    const current = m.locale ? m.locale('en') : m.lang('en'); // old versions of moment have .lang() function
    const step = this.step;
    const classNames = [];

    /**
     *
     * @param {number} value
     * @returns {String}
     */
    function even(value) {
      return (value / step % 2 == 0) ? ' vis-even' : ' vis-odd';
    }

    /**
     *
     * @param {Date} date
     * @returns {String}
     */
    function today(date) {
      if (date.isSame(Date.now(), 'day')) {
        return ' vis-today';
      }
      if (date.isSame(_moment().add(1, 'day'), 'day')) {
        return ' vis-tomorrow';
      }
      if (date.isSame(_moment().add(-1, 'day'), 'day')) {
        return ' vis-yesterday';
      }
      return '';
    }

    /**
     *
     * @param {Date} date
     * @returns {String}
     */
    function currentWeek(date) {
      return date.isSame(Date.now(), 'week') ? ' vis-current-week' : '';
    }

    /**
     *
     * @param {Date} date
     * @returns {String}
     */
    function currentMonth(date) {
      return date.isSame(Date.now(), 'month') ? ' vis-current-month' : '';
    }

    /**
     *
     * @param {Date} date
     * @returns {String}
     */
    function currentYear(date) {
      return date.isSame(Date.now(), 'year') ? ' vis-current-year' : '';
    }

    switch (this.scale) {
      case 'millisecond':
        classNames.push(today(current));
        classNames.push(even(current.milliseconds()));
        break;
      case 'second':
        classNames.push(today(current));
        classNames.push(even(current.seconds()));
        break;
      case 'minute':
        classNames.push(today(current));
        classNames.push(even(current.minutes()));
        break;
      case 'hour':
        classNames.push(`vis-h${current.hours()}${this.step == 4 ? '-h' + (current.hours() + 4) : ''}`);
        classNames.push(today(current));
        classNames.push(even(current.hours()));
        break;
      case 'weekday':
        classNames.push(`vis-${current.format('dddd').toLowerCase()}`);
        classNames.push(today(current));
        classNames.push(currentWeek(current));
        classNames.push(even(current.date()));
        break;
      case 'day':
        classNames.push(`vis-day${current.date()}`);
        classNames.push(`vis-${current.format('MMMM').toLowerCase()}`);
        classNames.push(today(current));
        classNames.push(currentMonth(current));
        classNames.push(this.step <= 2 ? today(current) : '');
        classNames.push(this.step <= 2 ? `vis-${current.format('dddd').toLowerCase()}` : '');
        classNames.push(even(current.date() - 1));
        break;
      case 'week':
        classNames.push(`vis-week${current.format('w')}`);
        classNames.push(currentWeek(current));
        classNames.push(even(current.week()));
        break;
      case 'month':
        classNames.push(`vis-${current.format('MMMM').toLowerCase()}`);
        classNames.push(currentMonth(current));
        classNames.push(even(current.month()));
        break;
      case 'year':
        classNames.push(`vis-year${current.year()}`);
        classNames.push(currentYear(current));
        classNames.push(even(current.year()));
        break;
    }
    return classNames.filter(String).join(" ");
  }
}

// Time formatting
TimeStep.FORMAT = {
  minorLabels: {
    millisecond:'SSS',
    second:     's',
    minute:     'HH:mm',
    hour:       'HH:mm',
    weekday:    'ddd D',
    day:        'D',
    week:       'w',
    month:      'MMM',
    year:       'YYYY'
  },
  majorLabels: {
    millisecond:'HH:mm:ss',
    second:     'D MMMM HH:mm',
    minute:     'ddd D MMMM',
    hour:       'ddd D MMMM',
    weekday:    'MMMM YYYY',
    day:        'MMMM YYYY',
    week:       'MMMM YYYY',
    month:      'YYYY',
    year:       ''
  }
};

/** A horizontal time axis */
class TimeAxis extends Component {
/**
 * @param {{dom: Object, domProps: Object, emitter: Emitter, range: Range}} body
 * @param {Object} [options]        See TimeAxis.setOptions for the available
 *                                  options.
 * @constructor TimeAxis
 * @extends Component
 */
  constructor(body, options) {
    super();
    this.dom = {
      foreground: null,
      lines: [],
      majorTexts: [],
      minorTexts: [],
      redundant: {
        lines: [],
        majorTexts: [],
        minorTexts: []
      }
    };
    this.props = {
      range: {
        start: 0,
        end: 0,
        minimumStep: 0
      },
      lineTop: 0
    };

    this.defaultOptions = {
      orientation: {
        axis: 'bottom'
      },  // axis orientation: 'top' or 'bottom'
      showMinorLabels: true,
      showMajorLabels: true,
      showWeekScale: false,
      maxMinorChars: 7,
      format: util$3.extend({}, TimeStep.FORMAT),
      moment: moment$1,
      timeAxis: null
    };
    this.options = util$3.extend({}, this.defaultOptions);

    this.body = body;

    // create the HTML DOM
    this._create();

    this.setOptions(options);
  }

  /**
   * Set options for the TimeAxis.
   * Parameters will be merged in current options.
   * @param {Object} options  Available options:
   *                          {string} [orientation.axis]
   *                          {boolean} [showMinorLabels]
   *                          {boolean} [showMajorLabels]
   *                          {boolean} [showWeekScale]
   */
  setOptions(options) {
    if (options) {
      // copy all options that we know
      util$3.selectiveExtend([
        'showMinorLabels',
        'showMajorLabels',
        'showWeekScale',
        'maxMinorChars',
        'hiddenDates',
        'timeAxis',
        'moment',
        'rtl'
      ], this.options, options);

      // deep copy the format options
      util$3.selectiveDeepExtend(['format'], this.options, options);

      if ('orientation' in options) {
        if (typeof options.orientation === 'string') {
          this.options.orientation.axis = options.orientation;
        }
        else if (typeof options.orientation === 'object' && 'axis' in options.orientation) {
          this.options.orientation.axis = options.orientation.axis;
        }
      }

      // apply locale to moment.js
      // TODO: not so nice, this is applied globally to moment.js
      if ('locale' in options) {
        if (typeof moment$1.locale === 'function') {
          // moment.js 2.8.1+
          moment$1.locale(options.locale);
        }
        else {
          moment$1.lang(options.locale);
        }
      }
    }
  }

  /**
   * Create the HTML DOM for the TimeAxis
   */
  _create() {
    this.dom.foreground = document.createElement('div');
    this.dom.background = document.createElement('div');

    this.dom.foreground.className = 'vis-time-axis vis-foreground';
    this.dom.background.className = 'vis-time-axis vis-background';
  }

  /**
   * Destroy the TimeAxis
   */
  destroy() {
    // remove from DOM
    if (this.dom.foreground.parentNode) {
      this.dom.foreground.parentNode.removeChild(this.dom.foreground);
    }
    if (this.dom.background.parentNode) {
      this.dom.background.parentNode.removeChild(this.dom.background);
    }

    this.body = null;
  }

  /**
   * Repaint the component
   * @return {boolean} Returns true if the component is resized
   */
  redraw() {
    const props = this.props;
    const foreground = this.dom.foreground;
    const background = this.dom.background;

    // determine the correct parent DOM element (depending on option orientation)
    const parent = (this.options.orientation.axis == 'top') ? this.body.dom.top : this.body.dom.bottom;
    const parentChanged = (foreground.parentNode !== parent);

    // calculate character width and height
    this._calculateCharSize();

    // TODO: recalculate sizes only needed when parent is resized or options is changed
    const showMinorLabels = this.options.showMinorLabels && this.options.orientation.axis !== 'none';
    const showMajorLabels = this.options.showMajorLabels && this.options.orientation.axis !== 'none';

    // determine the width and height of the elemens for the axis
    props.minorLabelHeight = showMinorLabels ? props.minorCharHeight : 0;
    props.majorLabelHeight = showMajorLabels ? props.majorCharHeight : 0;
    props.height = props.minorLabelHeight + props.majorLabelHeight;
    props.width = foreground.offsetWidth;

    props.minorLineHeight = this.body.domProps.root.height - props.majorLabelHeight -
        (this.options.orientation.axis == 'top' ? this.body.domProps.bottom.height : this.body.domProps.top.height);
    props.minorLineWidth = 1; // TODO: really calculate width
    props.majorLineHeight = props.minorLineHeight + props.majorLabelHeight;
    props.majorLineWidth = 1; // TODO: really calculate width

    //  take foreground and background offline while updating (is almost twice as fast)
    const foregroundNextSibling = foreground.nextSibling;
    const backgroundNextSibling = background.nextSibling;
    foreground.parentNode && foreground.parentNode.removeChild(foreground);
    background.parentNode && background.parentNode.removeChild(background);

    foreground.style.height = `${this.props.height}px`;

    this._repaintLabels();

    // put DOM online again (at the same place)
    if (foregroundNextSibling) {
      parent.insertBefore(foreground, foregroundNextSibling);
    }
    else {
      parent.appendChild(foreground);
    }
    if (backgroundNextSibling) {
      this.body.dom.backgroundVertical.insertBefore(background, backgroundNextSibling);
    }
    else {
      this.body.dom.backgroundVertical.appendChild(background);
    }
    return this._isResized() || parentChanged;
  }

  /**
   * Repaint major and minor text labels and vertical grid lines
   * @private
   */
  _repaintLabels() {
    const orientation = this.options.orientation.axis;

    // calculate range and step (step such that we have space for 7 characters per label)
    const start = util$3.convert(this.body.range.start, 'Number');
    const end = util$3.convert(this.body.range.end, 'Number');
    const timeLabelsize = this.body.util.toTime((this.props.minorCharWidth || 10) * this.options.maxMinorChars).valueOf();
    let minimumStep = timeLabelsize - getHiddenDurationBefore(this.options.moment, this.body.hiddenDates, this.body.range, timeLabelsize);
    minimumStep -= this.body.util.toTime(0).valueOf();

    const step = new TimeStep(new Date(start), new Date(end), minimumStep, this.body.hiddenDates, this.options);
    step.setMoment(this.options.moment);
    if (this.options.format) {
      step.setFormat(this.options.format);
    }
    if (this.options.timeAxis) {
      step.setScale(this.options.timeAxis);
    }
    this.step = step;

    // Move all DOM elements to a "redundant" list, where they
    // can be picked for re-use, and clear the lists with lines and texts.
    // At the end of the function _repaintLabels, left over elements will be cleaned up
    const dom = this.dom;
    dom.redundant.lines = dom.lines;
    dom.redundant.majorTexts = dom.majorTexts;
    dom.redundant.minorTexts = dom.minorTexts;
    dom.lines = [];
    dom.majorTexts = [];
    dom.minorTexts = [];

    let current;
    let next;
    let x;
    let xNext;
    let isMajor;
    let showMinorGrid;
    let width = 0;
    let prevWidth;
    let line;
    let xFirstMajorLabel = undefined;
    let count = 0;
    const MAX = 1000;
    let className;

    step.start();
    next = step.getCurrent();
    xNext = this.body.util.toScreen(next);
    while (step.hasNext() && count < MAX) {
      count++;

      isMajor = step.isMajor();
      className = step.getClassName();

      current = next;
      x = xNext;

      step.next();
      next = step.getCurrent();
      xNext = this.body.util.toScreen(next);

      prevWidth = width;
      width = xNext - x;
      switch (step.scale) {
        case 'week':         showMinorGrid = true; break;
        default:             showMinorGrid = (width >= prevWidth * 0.4); break; // prevent displaying of the 31th of the month on a scale of 5 days
      }

      if (this.options.showMinorLabels && showMinorGrid) {
        var label = this._repaintMinorText(x, step.getLabelMinor(current), orientation, className);
        label.style.width = `${width}px`; // set width to prevent overflow
      }

      if (isMajor && this.options.showMajorLabels) {
        if (x > 0) {
          if (xFirstMajorLabel == undefined) {
            xFirstMajorLabel = x;
          }
          label = this._repaintMajorText(x, step.getLabelMajor(current), orientation, className);
        }
        line = this._repaintMajorLine(x, width, orientation, className);
      }
      else { // minor line
        if (showMinorGrid) {
          line = this._repaintMinorLine(x, width, orientation, className);
        }
        else {
          if (line) {
            // adjust the width of the previous grid
            line.style.width = `${parseInt(line.style.width) + width}px`;
          }
        }
      }
    }

    if (count === MAX && !warnedForOverflow) {
        console.warn(`Something is wrong with the Timeline scale. Limited drawing of grid lines to ${MAX} lines.`);
        warnedForOverflow = true;
    }

    // create a major label on the left when needed
    if (this.options.showMajorLabels) {
      const leftTime = this.body.util.toTime(0); // upper bound estimation
      const leftText = step.getLabelMajor(leftTime);
      const widthText = leftText.length * (this.props.majorCharWidth || 10) + 10;

      if (xFirstMajorLabel == undefined || widthText < xFirstMajorLabel) {
        this._repaintMajorText(0, leftText, orientation, className);
      }
    }

    // Cleanup leftover DOM elements from the redundant list
    util$3.forEach(this.dom.redundant, arr => {
      while (arr.length) {
        const elem = arr.pop();
        if (elem && elem.parentNode) {
          elem.parentNode.removeChild(elem);
        }
      }
    });
  }

  /**
   * Create a minor label for the axis at position x
   * @param {number} x
   * @param {string} text
   * @param {string} orientation   "top" or "bottom" (default)
   * @param {string} className
   * @return {Element} Returns the HTML element of the created label
   * @private
   */
  _repaintMinorText(x, text, orientation, className) {
    // reuse redundant label
    let label = this.dom.redundant.minorTexts.shift();

    if (!label) {
      // create new label
      const content = document.createTextNode('');
      label = document.createElement('div');
      label.appendChild(content);
      this.dom.foreground.appendChild(label);
    }
    this.dom.minorTexts.push(label);
    label.innerHTML = util$3.xss(text);


    let y = (orientation == 'top') ? this.props.majorLabelHeight : 0;
    this._setXY(label, x, y);

    label.className = `vis-text vis-minor ${className}`;
    //label.title = title;  // TODO: this is a heavy operation

    return label;
  }

  /**
   * Create a Major label for the axis at position x
   * @param {number} x
   * @param {string} text
   * @param {string} orientation   "top" or "bottom" (default)
   * @param {string} className
   * @return {Element} Returns the HTML element of the created label
   * @private
   */
  _repaintMajorText(x, text, orientation, className) {
    // reuse redundant label
    let label = this.dom.redundant.majorTexts.shift();

    if (!label) {
      // create label
      const content = document.createElement('div');
      label = document.createElement('div');
      label.appendChild(content);
      this.dom.foreground.appendChild(label);
    }

    label.childNodes[0].innerHTML = util$3.xss(text);
    label.className = `vis-text vis-major ${className}`;
    //label.title = title; // TODO: this is a heavy operation

    let y = (orientation == 'top') ? 0 : this.props.minorLabelHeight;
    this._setXY(label, x, y);

    this.dom.majorTexts.push(label);
    return label;
  }

  /**
   * sets xy
   * @param {string} label
   * @param {number} x
   * @param {number} y
   * @private
   */
  _setXY(label, x, y) {
    // If rtl is true, inverse x.
    const directionX = this.options.rtl ? (x * -1) : x;
    label.style.transform = `translate(${directionX}px, ${y}px)`;
  }

  /**
   * Create a minor line for the axis at position x
   * @param {number} left
   * @param {number} width
   * @param {string} orientation   "top" or "bottom" (default)
   * @param {string} className
   * @return {Element} Returns the created line
   * @private
   */
  _repaintMinorLine(left, width, orientation, className) {
    // reuse redundant line
    let line = this.dom.redundant.lines.shift();
    if (!line) {
      // create vertical line
      line = document.createElement('div');
      this.dom.background.appendChild(line);
    }
    this.dom.lines.push(line);

    const props = this.props;
    
    line.style.width = `${width}px`;
    line.style.height = `${props.minorLineHeight}px`;

    let y = (orientation == 'top') ? props.majorLabelHeight : this.body.domProps.top.height;
    let x = left - props.minorLineWidth / 2;

    this._setXY(line, x, y);
    line.className = `vis-grid ${this.options.rtl ?  'vis-vertical-rtl' : 'vis-vertical'} vis-minor ${className}`;

    return line;
  }

  /**
   * Create a Major line for the axis at position x
   * @param {number} left
   * @param {number} width
   * @param {string} orientation   "top" or "bottom" (default)
   * @param {string} className
   * @return {Element} Returns the created line
   * @private
   */
  _repaintMajorLine(left, width, orientation, className) {
    // reuse redundant line
    let line = this.dom.redundant.lines.shift();
    if (!line) {
      // create vertical line
      line = document.createElement('div');
      this.dom.background.appendChild(line);
    }
    this.dom.lines.push(line);

    const props = this.props;
    
    line.style.width = `${width}px`;
    line.style.height = `${props.majorLineHeight}px`;

    let y = (orientation == 'top') ? 0 : this.body.domProps.top.height;
    let x = left - props.majorLineWidth / 2;

    this._setXY(line, x, y);
    line.className = `vis-grid ${this.options.rtl ?  'vis-vertical-rtl' : 'vis-vertical'} vis-major ${className}`;

    return line;
  }

  /**
   * Determine the size of text on the axis (both major and minor axis).
   * The size is calculated only once and then cached in this.props.
   * @private
   */
  _calculateCharSize() {
    // Note: We calculate char size with every redraw. Size may change, for
    // example when any of the timelines parents had display:none for example.

    // determine the char width and height on the minor axis
    if (!this.dom.measureCharMinor) {
      this.dom.measureCharMinor = document.createElement('DIV');
      this.dom.measureCharMinor.className = 'vis-text vis-minor vis-measure';
      this.dom.measureCharMinor.style.position = 'absolute';

      this.dom.measureCharMinor.appendChild(document.createTextNode('0'));
      this.dom.foreground.appendChild(this.dom.measureCharMinor);
    }
    this.props.minorCharHeight = this.dom.measureCharMinor.clientHeight;
    this.props.minorCharWidth = this.dom.measureCharMinor.clientWidth;

    // determine the char width and height on the major axis
    if (!this.dom.measureCharMajor) {
      this.dom.measureCharMajor = document.createElement('DIV');
      this.dom.measureCharMajor.className = 'vis-text vis-major vis-measure';
      this.dom.measureCharMajor.style.position = 'absolute';

      this.dom.measureCharMajor.appendChild(document.createTextNode('0'));
      this.dom.foreground.appendChild(this.dom.measureCharMajor);
    }
    this.props.majorCharHeight = this.dom.measureCharMajor.clientHeight;
    this.props.majorCharWidth = this.dom.measureCharMajor.clientWidth;
  }
}


var warnedForOverflow = false;

/**
 * Turn an element into an clickToUse element.
 * When not active, the element has a transparent overlay. When the overlay is
 * clicked, the mode is changed to active.
 * When active, the element is displayed with a blue border around it, and
 * the interactive contents of the element can be used. When clicked outside
 * the element, the elements mode is changed to inactive.
 * @param {Element} container
 * @constructor Activator
 */
function Activator$2(container) {
  this.active = false;

  this.dom = {
    container: container
  };

  this.dom.overlay = document.createElement('div');
  this.dom.overlay.className = 'vis-overlay';

  this.dom.container.appendChild(this.dom.overlay);

  this.hammer = Hammer$2(this.dom.overlay);
  this.hammer.on('tap', this._onTapOverlay.bind(this));

  // block all touch events (except tap)
  var me = this;
  var events = [
    'tap', 'doubletap', 'press',
    'pinch',
    'pan', 'panstart', 'panmove', 'panend'
  ];
  events.forEach(function (event) {
    me.hammer.on(event, function (event) {
      event.stopPropagation();
    });
  });

  // attach a click event to the window, in order to deactivate when clicking outside the timeline
  if (document && document.body) {
    this.onClick = function (event) {
      if (!_hasParent$1(event.target, container)) {
        me.deactivate();
      }
    };
    document.body.addEventListener('click', this.onClick);
  }

  if (this.keycharm !== undefined) {
    this.keycharm.destroy();
  }
  this.keycharm = keycharm();

  // keycharm listener only bounded when active)
  this.escListener = this.deactivate.bind(this);
}

// turn into an event emitter
componentEmitter(Activator$2.prototype);

// The currently active activator
Activator$2.current = null;

/**
 * Destroy the activator. Cleans up all created DOM and event listeners
 */
Activator$2.prototype.destroy = function () {
  this.deactivate();

  // remove dom
  this.dom.overlay.parentNode.removeChild(this.dom.overlay);

  // remove global event listener
  if (this.onClick) {
    document.body.removeEventListener('click', this.onClick);
  }
  // remove keycharm
  if (this.keycharm !== undefined) {
    this.keycharm.destroy();
  }
  this.keycharm = null;
  // cleanup hammer instances
  this.hammer.destroy();
  this.hammer = null;
  // FIXME: cleaning up hammer instances doesn't work (Timeline not removed from memory)
};

/**
 * Activate the element
 * Overlay is hidden, element is decorated with a blue shadow border
 */
Activator$2.prototype.activate = function () {
  // we allow only one active activator at a time
  if (Activator$2.current) {
    Activator$2.current.deactivate();
  }
  Activator$2.current = this;

  this.active = true;
  this.dom.overlay.style.display = 'none';
  util$3.addClassName(this.dom.container, 'vis-active');

  this.emit('change');
  this.emit('activate');

  // ugly hack: bind ESC after emitting the events, as the Network rebinds all
  // keyboard events on a 'change' event
  this.keycharm.bind('esc', this.escListener);
};

/**
 * Deactivate the element
 * Overlay is displayed on top of the element
 */
Activator$2.prototype.deactivate = function () {
  if (Activator$2.current === this) {
    Activator$2.current = null;
  }

  this.active = false;
  this.dom.overlay.style.display = '';
  util$3.removeClassName(this.dom.container, 'vis-active');
  this.keycharm.unbind('esc', this.escListener);

  this.emit('change');
  this.emit('deactivate');
};

/**
 * Handle a tap event: activate the container
 * @param {Event}  event   The event
 * @private
 */
Activator$2.prototype._onTapOverlay = function (event) {
  // activate the container
  this.activate();
  event.stopPropagation();
};

/**
 * Test whether the element has the requested parent element somewhere in
 * its chain of parent nodes.
 * @param {HTMLElement} element
 * @param {HTMLElement} parent
 * @returns {boolean} Returns true when the parent is found somewhere in the
 *                    chain of parent nodes.
 * @private
 */
function _hasParent$1(element, parent) {
  while (element) {
    if (element === parent) {
      return true
    }
    element = element.parentNode;
  }
  return false;
}

/*
 * IMPORTANT: Locales for Moment has to be imported in the legacy and standalone
 * entry points. For the peer build it's users responsibility to do so.
 */

// English
const en = {
  current: 'current',
  time: 'time',
  deleteSelected: 'Delete selected',
};
const en_EN = en;
const en_US = en;

// Italiano
const it = {
  current: 'attuale',
  time: 'tempo',
  deleteSelected: 'Cancella la selezione',
};
const it_IT = it;
const it_CH = it;

// Dutch
const nl = {
  current: 'huidige',
  time: 'tijd',
  deleteSelected: 'Selectie verwijderen'
};
const nl_NL = nl;
const nl_BE = nl;

// German
const de = {
  current: 'Aktuelle',
  time: 'Zeit',
  deleteSelected: 'L\u00f6sche Auswahl',
};
const de_DE = de;

// French
const fr = {
  current: 'actuel',
  time: 'heure',
  deleteSelected: 'Effacer la selection',
};
const fr_FR = fr;
const fr_CA = fr;
const fr_BE = fr;

// Espanol
const es = {
  current: 'corriente',
  time: 'hora',
  deleteSelected: 'Eliminar selecci\u00f3n',
};
const es_ES = es;

// Ukrainian
const uk = {
  current: 'поточний',
  time: 'час',
  deleteSelected: 'Видалити обране',
};
const uk_UA = uk;

// Russian
const ru = {
  current: 'текущее',
  time: 'время',
  deleteSelected: 'Удалить выбранное',
};
const ru_RU = ru;

// Polish
const pl = {
  current: 'aktualny',
  time: 'czas',
  deleteSelected: 'Usuń wybrane',
};
const pl_PL = pl;

// Portuguese
const pt = {
  current: 'atual',
  time: 'data',
  deleteSelected: 'Apagar selecionado',
};
const pt_BR = pt;
const pt_PT = pt;

// Japanese
const ja = {
  current: '現在',
  time: '時刻',
  deleteSelected: '選択されたものを削除',
};
const ja_JP = ja;

const locales = {
  en,
  en_EN,
  en_US,
  it,
  it_IT,
  it_CH,
  nl,
  nl_NL,
  nl_BE,
  de,
  de_DE,
  fr,
  fr_FR,
  fr_CA,
  fr_BE,
  es,
  es_ES,
  uk,
  uk_UA,
  ru,
  ru_RU,
  pl,
  pl_PL,
  pt,
  pt_BR,
  pt_PT,
  ja,
  ja_JP,
};

/** A custom time bar */
class CustomTime extends Component {
 /**
 * @param {{range: Range, dom: Object}} body
 * @param {Object} [options]        Available parameters:
 *                                  {number | string} id
 *                                  {string} locales
 *                                  {string} locale
 * @constructor CustomTime
 * @extends Component
 */
  constructor(body, options) {
    super();
    this.body = body;

    // default options
    this.defaultOptions = {
      moment: moment$1,
      locales,
      locale: 'en',
      id: undefined,
      title: undefined
    };
    this.options = util$3.extend({}, this.defaultOptions);
    this.setOptions(options);
    this.options.locales = util$3.extend({}, locales, this.options.locales);
    const defaultLocales = this.defaultOptions.locales[this.defaultOptions.locale];
    Object.keys(this.options.locales).forEach(locale => {
      this.options.locales[locale] = util$3.extend(
        {},
        defaultLocales,
        this.options.locales[locale]
      );
    });

    if (options && options.time != null) {
      this.customTime = options.time;
    } else {
      this.customTime = new Date();
    }

    this.eventParams = {}; // stores state parameters while dragging the bar

    // create the DOM
    this._create();
  }

  /**
   * Set options for the component. Options will be merged in current options.
   * @param {Object} options  Available parameters:
   *                                  {number | string} id
   *                                  {string} locales
   *                                  {string} locale
   */
  setOptions(options) {
    if (options) {
      // copy all options that we know
      util$3.selectiveExtend(['moment', 'locale', 'locales', 'id', 'title', 'rtl', 'snap'], this.options, options);
    }
  }

  /**
   * Create the DOM for the custom time
   * @private
   */
  _create() {
    const bar = document.createElement('div');
    bar['custom-time'] = this;
    bar.className = `vis-custom-time ${this.options.id || ''}`;
    bar.style.position = 'absolute';
    bar.style.top = '0px';
    bar.style.height = '100%';
    this.bar = bar;

    const drag = document.createElement('div');
    drag.style.position = 'relative';
    drag.style.top = '0px';
    if(this.options.rtl) {
      drag.style.right = '-10px';
    } else  {
       drag.style.left = '-10px';
    }
    drag.style.height = '100%';
    drag.style.width = '20px';

    /**
     *
     * @param {WheelEvent} e
     */
    function onMouseWheel (e) {
      this.body.range._onMouseWheel(e);
    }

    if (drag.addEventListener) {
      // IE9, Chrome, Safari, Opera
      drag.addEventListener("mousewheel", onMouseWheel.bind(this), false);
      // Firefox
      drag.addEventListener("DOMMouseScroll", onMouseWheel.bind(this), false);
    } else {
      // IE 6/7/8
      drag.attachEvent("onmousewheel", onMouseWheel.bind(this));
    }

    bar.appendChild(drag);
    // attach event listeners
    this.hammer = new Hammer$2(drag);
    this.hammer.on('panstart', this._onDragStart.bind(this));
    this.hammer.on('panmove',  this._onDrag.bind(this));
    this.hammer.on('panend',   this._onDragEnd.bind(this));
    this.hammer.get('pan').set({threshold:5, direction: Hammer$2.DIRECTION_ALL});
  }

  /**
   * Destroy the CustomTime bar
   */
  destroy() {
    this.hide();

    this.hammer.destroy();
    this.hammer = null;

    this.body = null;
  }

  /**
   * Repaint the component
   * @return {boolean} Returns true if the component is resized
   */
  redraw() {
    const parent = this.body.dom.backgroundVertical;
    if (this.bar.parentNode != parent) {
      // attach to the dom
      if (this.bar.parentNode) {
        this.bar.parentNode.removeChild(this.bar);
      }
      parent.appendChild(this.bar);
    }

    const x = this.body.util.toScreen(this.customTime);

    let locale = this.options.locales[this.options.locale];
    if (!locale) {
      if (!this.warned) {
        console.warn(`WARNING: options.locales['${this.options.locale}'] not found. See https://visjs.github.io/vis-timeline/docs/timeline/#Localization`);
        this.warned = true;
      }
      locale = this.options.locales['en']; // fall back on english when not available
    }

    let title = this.options.title;
    // To hide the title completely use empty string ''.
    if (title === undefined) {
      title = `${locale.time}: ${this.options.moment(this.customTime).format('dddd, MMMM Do YYYY, H:mm:ss')}`;
      title = title.charAt(0).toUpperCase() + title.substring(1);
    } else if (typeof title === "function") {
      title = title.call(this, this.customTime);
    }

    this.options.rtl ? this.bar.style.right = `${x}px` : this.bar.style.left = `${x}px`;
    this.bar.title = title;

    return false;
  }

  /**
   * Remove the CustomTime from the DOM
   */
  hide() {
    // remove the line from the DOM
    if (this.bar.parentNode) {
      this.bar.parentNode.removeChild(this.bar);
    }
  }

  /**
   * Set custom time.
   * @param {Date | number | string} time
   */
  setCustomTime(time) {
    this.customTime = util$3.convert(time, 'Date');
    this.redraw();
  }

  /**
   * Retrieve the current custom time.
   * @return {Date} customTime
   */
  getCustomTime() {
    return new Date(this.customTime.valueOf());
  }

  /**
   * Set custom marker.
   * @param {string} [title] Title of the custom marker
   * @param {boolean} [editable] Make the custom marker editable.
   */
  setCustomMarker(title, editable) {
    const marker = document.createElement('div');
    marker.className = `vis-custom-time-marker`;
    marker.innerHTML = util$3.xss(title);
    marker.style.position = 'absolute';

    if (editable) {
      marker.setAttribute('contenteditable', 'true');
      marker.addEventListener('pointerdown', function () {
        marker.focus();
      });
      marker.addEventListener('input', this._onMarkerChange.bind(this));
      // The editable div element has no change event, so here emulates the change event.
      marker.title = title;
      marker.addEventListener('blur', function (event) {
        if (this.title != event.target.innerHTML) {
          this._onMarkerChanged(event);
          this.title = event.target.innerHTML;
        }
      }.bind(this));
    }

    this.bar.appendChild(marker);
  }

  /**
    * Set custom title.
    * @param {Date | number | string} title
    */
  setCustomTitle(title) {
    this.options.title = title;
  }

  /**
   * Start moving horizontally
   * @param {Event} event
   * @private
   */
  _onDragStart(event) {
    this.eventParams.dragging = true;
    this.eventParams.customTime = this.customTime;

    event.stopPropagation();
  }

  /**
   * Perform moving operating.
   * @param {Event} event
   * @private
   */
  _onDrag(event) {
    if (!this.eventParams.dragging) return;

    let deltaX = this.options.rtl ? (-1) * event.deltaX : event.deltaX;

    const x = this.body.util.toScreen(this.eventParams.customTime) + deltaX;
    const time = this.body.util.toTime(x);

    const scale = this.body.util.getScale();
    const step = this.body.util.getStep();
    const snap = this.options.snap;

    const snappedTime = snap ? snap(time, scale, step) : time;

    this.setCustomTime(snappedTime);

    // fire a timechange event
    this.body.emitter.emit('timechange', {
      id: this.options.id,
      time: new Date(this.customTime.valueOf()),
      event
    });

    event.stopPropagation();
  }

  /**
   * Stop moving operating.
   * @param {Event} event
   * @private
   */
  _onDragEnd(event) {
    if (!this.eventParams.dragging) return;

    // fire a timechanged event
    this.body.emitter.emit('timechanged', {
      id: this.options.id,
      time: new Date(this.customTime.valueOf()),
      event
    });

    event.stopPropagation();
  }

  /**
   * Perform input operating.
   * @param {Event} event
   * @private
   */
  _onMarkerChange(event) {
    this.body.emitter.emit('markerchange', {
      id: this.options.id,
      title: event.target.innerHTML,
      event
    });

    event.stopPropagation();
  }

  /**
   * Perform change operating.
   * @param {Event} event
   * @private
   */
  _onMarkerChanged(event) {
    this.body.emitter.emit('markerchanged', {
      id: this.options.id,
      title: event.target.innerHTML,
      event
    });

    event.stopPropagation();
  }

  /**
   * Find a custom time from an event target:
   * searches for the attribute 'custom-time' in the event target's element tree
   * @param {Event} event
   * @return {CustomTime | null} customTime
   */
  static customTimeFromTarget(event) {
    let target = event.target;
    while (target) {
      if (target.hasOwnProperty('custom-time')) {
        return target['custom-time'];
      }
      target = target.parentNode;
    }

    return null;
  }
}

/**
 * Create a timeline visualization
 * @constructor Core
 */
class Core {
  /**
   * Create the main DOM for the Core: a root panel containing left, right,
   * top, bottom, content, and background panel.
   * @param {Element} container  The container element where the Core will
   *                             be attached.
   * @protected
   */
  _create(container) {
    this.dom = {};

    this.dom.container = container;
    this.dom.container.style.position = 'relative';

    this.dom.root                 = document.createElement('div');
    this.dom.background           = document.createElement('div');
    this.dom.backgroundVertical   = document.createElement('div');
    this.dom.backgroundHorizontal = document.createElement('div');
    this.dom.centerContainer      = document.createElement('div');
    this.dom.leftContainer        = document.createElement('div');
    this.dom.rightContainer       = document.createElement('div');
    this.dom.center               = document.createElement('div');
    this.dom.left                 = document.createElement('div');
    this.dom.right                = document.createElement('div');
    this.dom.top                  = document.createElement('div');
    this.dom.bottom               = document.createElement('div');
    this.dom.shadowTop            = document.createElement('div');
    this.dom.shadowBottom         = document.createElement('div');
    this.dom.shadowTopLeft        = document.createElement('div');
    this.dom.shadowBottomLeft     = document.createElement('div');
    this.dom.shadowTopRight       = document.createElement('div');
    this.dom.shadowBottomRight    = document.createElement('div');
    this.dom.rollingModeBtn       = document.createElement('div');
    this.dom.loadingScreen        = document.createElement('div');

    this.dom.root.className                 = 'vis-timeline';
    this.dom.background.className           = 'vis-panel vis-background';
    this.dom.backgroundVertical.className   = 'vis-panel vis-background vis-vertical';
    this.dom.backgroundHorizontal.className = 'vis-panel vis-background vis-horizontal';
    this.dom.centerContainer.className      = 'vis-panel vis-center';
    this.dom.leftContainer.className        = 'vis-panel vis-left';
    this.dom.rightContainer.className       = 'vis-panel vis-right';
    this.dom.top.className                  = 'vis-panel vis-top';
    this.dom.bottom.className               = 'vis-panel vis-bottom';
    this.dom.left.className                 = 'vis-content';
    this.dom.center.className               = 'vis-content';
    this.dom.right.className                = 'vis-content';
    this.dom.shadowTop.className            = 'vis-shadow vis-top';
    this.dom.shadowBottom.className         = 'vis-shadow vis-bottom';
    this.dom.shadowTopLeft.className        = 'vis-shadow vis-top';
    this.dom.shadowBottomLeft.className     = 'vis-shadow vis-bottom';
    this.dom.shadowTopRight.className       = 'vis-shadow vis-top';
    this.dom.shadowBottomRight.className    = 'vis-shadow vis-bottom';
    this.dom.rollingModeBtn.className       = 'vis-rolling-mode-btn';
    this.dom.loadingScreen.className        = 'vis-loading-screen';

    this.dom.root.appendChild(this.dom.background);
    this.dom.root.appendChild(this.dom.backgroundVertical);
    this.dom.root.appendChild(this.dom.backgroundHorizontal);
    this.dom.root.appendChild(this.dom.centerContainer);
    this.dom.root.appendChild(this.dom.leftContainer);
    this.dom.root.appendChild(this.dom.rightContainer);
    this.dom.root.appendChild(this.dom.top);
    this.dom.root.appendChild(this.dom.bottom);
    this.dom.root.appendChild(this.dom.rollingModeBtn);

    this.dom.centerContainer.appendChild(this.dom.center);
    this.dom.leftContainer.appendChild(this.dom.left);
    this.dom.rightContainer.appendChild(this.dom.right);
    this.dom.centerContainer.appendChild(this.dom.shadowTop);
    this.dom.centerContainer.appendChild(this.dom.shadowBottom);
    this.dom.leftContainer.appendChild(this.dom.shadowTopLeft);
    this.dom.leftContainer.appendChild(this.dom.shadowBottomLeft);
    this.dom.rightContainer.appendChild(this.dom.shadowTopRight);
    this.dom.rightContainer.appendChild(this.dom.shadowBottomRight);
    
    // size properties of each of the panels
    this.props = {
      root: {},
      background: {},
      centerContainer: {},
      leftContainer: {},
      rightContainer: {},
      center: {},
      left: {},
      right: {},
      top: {},
      bottom: {},
      border: {},
      scrollTop: 0,
      scrollTopMin: 0
    };

    this.on('rangechange', () => {
      if (this.initialDrawDone === true) {
        this._redraw();
      }
    });
    this.on('rangechanged', () => {
      if (!this.initialRangeChangeDone) {
        this.initialRangeChangeDone = true;
      }
    });
    this.on('touch',       this._onTouch.bind(this));
    this.on('panmove',         this._onDrag.bind(this));

    const me = this;
    this._origRedraw = this._redraw.bind(this);
    this._redraw = util$3.throttle(this._origRedraw);

    this.on('_change', properties => {
      if (me.itemSet && me.itemSet.initialItemSetDrawn && properties && properties.queue == true) {
        me._redraw();
      } else {
        me._origRedraw();
      }
    });

    // create event listeners for all interesting events, these events will be
    // emitted via emitter
    this.hammer = new Hammer$2(this.dom.root);
    const pinchRecognizer = this.hammer.get('pinch').set({enable: true});
    pinchRecognizer && disablePreventDefaultVertically(pinchRecognizer);
    this.hammer.get('pan').set({threshold:5, direction: Hammer$2.DIRECTION_ALL});
    this.timelineListeners = {};

    const events = [
      'tap', 'doubletap', 'press',
      'pinch',
      'pan', 'panstart', 'panmove', 'panend'
        // TODO: cleanup
      //'touch', 'pinch',
      //'tap', 'doubletap', 'hold',
      //'dragstart', 'drag', 'dragend',
      //'mousewheel', 'DOMMouseScroll' // DOMMouseScroll is needed for Firefox
    ];
    events.forEach(type => {
      const listener = event => {
        if (me.isActive()) {
          me.emit(type, event);
        }
      };
      me.hammer.on(type, listener);
      me.timelineListeners[type] = listener;
    });

    // emulate a touch event (emitted before the start of a pan, pinch, tap, or press)
    onTouch(this.hammer, event => {
      me.emit('touch', event);
    });

    // emulate a release event (emitted after a pan, pinch, tap, or press)
    onRelease(this.hammer, event => {
      me.emit('release', event);
    });

    /**
     *
     * @param {WheelEvent} event
     */
    function onMouseWheel(event) {

      // Reasonable default wheel deltas
      const LINE_HEIGHT = 40;
      const PAGE_HEIGHT = 800;

      if (this.isActive()) {
        this.emit('mousewheel', event);
      }

      // deltaX and deltaY normalization from jquery.mousewheel.js
      let deltaX = 0;
      let deltaY = 0;

      // Old school scrollwheel delta
      if ( 'detail'      in event ) { deltaY = event.detail * -1;      }
      if ( 'wheelDelta'  in event ) { deltaY = event.wheelDelta;       }
      if ( 'wheelDeltaY' in event ) { deltaY = event.wheelDeltaY;      }
      if ( 'wheelDeltaX' in event ) { deltaX = event.wheelDeltaX * -1; }

      // Firefox < 17 horizontal scrolling related to DOMMouseScroll event
      if ( 'axis' in event && event.axis === event.HORIZONTAL_AXIS ) {
        deltaX = deltaY * -1;
        deltaY = 0;
      }

      // New school wheel delta (wheel event)
      if ( 'deltaY' in event ) {
        deltaY = event.deltaY * -1;
      }
      if ( 'deltaX' in event ) {
        deltaX = event.deltaX;
      }

      // Normalize deltas
      if (event.deltaMode) {
          if (event.deltaMode === 1) {   // delta in LINE units
            deltaX *= LINE_HEIGHT;
            deltaY *= LINE_HEIGHT;
          } else {                       // delta in PAGE units
            deltaX *= LINE_HEIGHT;
            deltaY *= PAGE_HEIGHT;
          }
        }
        // Prevent scrolling when zooming (no zoom key, or pressing zoom key)
      if (this.options.preferZoom) {
        if (!this.options.zoomKey || event[this.options.zoomKey]) return;
      } else {
        if (this.options.zoomKey && event[this.options.zoomKey]) return
      }
      // Don't preventDefault if you can't scroll
      if (!this.options.verticalScroll && !this.options.horizontalScroll) return;

      if (this.options.verticalScroll && Math.abs(deltaY) >= Math.abs(deltaX)) {
        const current = this.props.scrollTop;
        const adjusted = current + deltaY;

        if (this.isActive()) {
          const newScrollTop = this._setScrollTop(adjusted);

          if (newScrollTop !== current) {
            this._redraw();
            this.emit('scroll', event);

            // Prevent default actions caused by mouse wheel
            // (else the page and timeline both scroll)
            event.preventDefault();
          }
        }
      } else if (this.options.horizontalScroll) {
        const delta = Math.abs(deltaX) >= Math.abs(deltaY) ? deltaX : deltaY;

        // calculate a single scroll jump relative to the range scale
        const diff = (delta / 120) * (this.range.end - this.range.start) / 20;
        // calculate new start and end
        const newStart = this.range.start + diff;
        const newEnd = this.range.end + diff;

        const options = {
          animation: false,
          byUser: true,
          event
        };
        this.range.setRange(newStart, newEnd, options);

        event.preventDefault();
      }
    }

    // Add modern wheel event listener
    const wheelType = "onwheel" in document.createElement("div") ? "wheel" : // Modern browsers support "wheel"
    document.onmousewheel !== undefined ? "mousewheel" : // Webkit and IE support at least "mousewheel"
    
    // DOMMouseScroll - Older Firefox versions use "DOMMouseScroll"
    // onmousewheel - All the use "onmousewheel"
    this.dom.centerContainer.addEventListener ? "DOMMouseScroll" :  "onmousewheel";
    this.dom.top.addEventListener ? "DOMMouseScroll" : "onmousewheel";
    this.dom.bottom.addEventListener ? "DOMMouseScroll" : "onmousewheel";
    this.dom.centerContainer.addEventListener(wheelType, onMouseWheel.bind(this), false);
    this.dom.top.addEventListener(wheelType, onMouseWheel.bind(this), false);
    this.dom.bottom.addEventListener(wheelType, onMouseWheel.bind(this), false);


    /**
     *
     * @param {scroll} event
     */
    function onMouseScrollSide(event) {
      if (!me.options.verticalScroll) return;
      
      event.preventDefault();
      if (me.isActive()) {
        const adjusted = -event.target.scrollTop;
        me._setScrollTop(adjusted);
        me._redraw();
        me.emit('scrollSide', event);
      }
    }

    this.dom.left.parentNode.addEventListener('scroll', onMouseScrollSide.bind(this));
    this.dom.right.parentNode.addEventListener('scroll', onMouseScrollSide.bind(this));

    let itemAddedToTimeline = false;

    /**
     *
     * @param {dragover} event
     * @returns {boolean}
     */
    function handleDragOver(event) {
      if (event.preventDefault) {
        me.emit('dragover', me.getEventProperties(event));
        event.preventDefault(); // Necessary. Allows us to drop.
      }

      // make sure your target is a timeline element
      if (!(event.target.className.indexOf("timeline") > -1)) return;

      // make sure only one item is added every time you're over the timeline
      if (itemAddedToTimeline) return;

      event.dataTransfer.dropEffect = 'move';  
      itemAddedToTimeline = true;
      return false;
    }

    /**
     *
     * @param {drop} event
     * @returns {boolean}
     */
    function handleDrop(event) {
      // prevent redirect to blank page - Firefox
      if(event.preventDefault) { event.preventDefault(); }
      if(event.stopPropagation) { event.stopPropagation(); }
      // return when dropping non-timeline items
      try {
        var itemData = JSON.parse(event.dataTransfer.getData("text"));
        if (!itemData || !itemData.content) return
      } catch (err) {
        return false;
      }

      itemAddedToTimeline = false;
      event.center = {
        x: event.clientX,
        y: event.clientY
      };

      if (itemData.target !== 'item') {
        me.itemSet._onAddItem(event);
      } else {
        me.itemSet._onDropObjectOnItem(event);
      }
      me.emit('drop', me.getEventProperties(event));
      return false;
    }

    this.dom.center.addEventListener('dragover', handleDragOver.bind(this), false);
    this.dom.center.addEventListener('drop', handleDrop.bind(this), false);

    this.customTimes = [];

    // store state information needed for touch events
    this.touch = {};

    this.redrawCount = 0;
    this.initialDrawDone = false;
    this.initialRangeChangeDone = false;

    // attach the root panel to the provided container
    if (!container) throw new Error('No container provided');
    container.appendChild(this.dom.root);
    container.appendChild(this.dom.loadingScreen);
  }

  /**
   * Set options. Options will be passed to all components loaded in the Timeline.
   * @param {Object} [options]
   *                           {String} orientation
   *                              Vertical orientation for the Timeline,
   *                              can be 'bottom' (default) or 'top'.
   *                           {string | number} width
   *                              Width for the timeline, a number in pixels or
   *                              a css string like '1000px' or '75%'. '100%' by default.
   *                           {string | number} height
   *                              Fixed height for the Timeline, a number in pixels or
   *                              a css string like '400px' or '75%'. If undefined,
   *                              The Timeline will automatically size such that
   *                              its contents fit.
   *                           {string | number} minHeight
   *                              Minimum height for the Timeline, a number in pixels or
   *                              a css string like '400px' or '75%'.
   *                           {string | number} maxHeight
   *                              Maximum height for the Timeline, a number in pixels or
   *                              a css string like '400px' or '75%'.
   *                           {number | Date | string} start
   *                              Start date for the visible window
   *                           {number | Date | string} end
   *                              End date for the visible window
   */
  setOptions(options) {
    if (options) {
      // copy the known options
      const fields = [
        'width', 'height', 'minHeight', 'maxHeight', 'autoResize',
        'start', 'end', 'clickToUse', 'dataAttributes', 'hiddenDates',
        'locale', 'locales', 'moment', 'preferZoom', 'rtl', 'zoomKey',
        'horizontalScroll', 'verticalScroll', 'longSelectPressTime', 'snap'
      ];
      util$3.selectiveExtend(fields, this.options, options);
      this.dom.rollingModeBtn.style.visibility = 'hidden';

      if (this.options.rtl) {
        this.dom.container.style.direction = "rtl";
        this.dom.backgroundVertical.className = 'vis-panel vis-background vis-vertical-rtl';    
      }

      if (this.options.verticalScroll) {
        if (this.options.rtl) {
          this.dom.rightContainer.className = 'vis-panel vis-right vis-vertical-scroll';
        } else {
          this.dom.leftContainer.className = 'vis-panel vis-left vis-vertical-scroll';
        }
      }

      if (typeof this.options.orientation !== 'object') {
        this.options.orientation = {item:undefined,axis:undefined};
      }
      if ('orientation' in options) {
        if (typeof options.orientation === 'string') {
          this.options.orientation = {
            item: options.orientation,
            axis: options.orientation
          };
        }
        else if (typeof options.orientation === 'object') {
          if ('item' in options.orientation) {
            this.options.orientation.item = options.orientation.item;
          }
          if ('axis' in options.orientation) {
            this.options.orientation.axis = options.orientation.axis;
          }
        }
      }

      if (this.options.orientation.axis === 'both') {
        if (!this.timeAxis2) {
          const timeAxis2 = this.timeAxis2 = new TimeAxis(this.body);
          timeAxis2.setOptions = options => {
            const _options = options ? util$3.extend({}, options) : {};
            _options.orientation = 'top'; // override the orientation option, always top
            TimeAxis.prototype.setOptions.call(timeAxis2, _options);
          };
          this.components.push(timeAxis2);
        }
      }
      else {
        if (this.timeAxis2) {
          const index = this.components.indexOf(this.timeAxis2);
          if (index !== -1) {
            this.components.splice(index, 1);
          }
          this.timeAxis2.destroy();
          this.timeAxis2 = null;
        }
      }

      // if the graph2d's drawPoints is a function delegate the callback to the onRender property
      if (typeof options.drawPoints == 'function') {
        options.drawPoints = {
            onRender: options.drawPoints
        };
      }

      if ('hiddenDates' in this.options) {
        convertHiddenOptions(this.options.moment, this.body, this.options.hiddenDates);
      }

      if ('clickToUse' in options) {
        if (options.clickToUse) {
          if (!this.activator) {
            this.activator = new Activator$2(this.dom.root);
          }
        }
        else {
          if (this.activator) {
            this.activator.destroy();
            delete this.activator;
          }
        }
      }

      // enable/disable autoResize
      this._initAutoResize();
    }

    // propagate options to all components
    this.components.forEach(component => component.setOptions(options));

    // enable/disable configure
    if ('configure' in options) {
      if (!this.configurator) {
        this.configurator = this._createConfigurator();
      }

      this.configurator.setOptions(options.configure);

      // collect the settings of all components, and pass them to the configuration system
      const appliedOptions = util$3.deepExtend({}, this.options);
      this.components.forEach(component => {
        util$3.deepExtend(appliedOptions, component.options);
      });
      this.configurator.setModuleOptions({global: appliedOptions});
    }

    this._redraw();
  }

  /**
   * Returns true when the Timeline is active.
   * @returns {boolean}
   */
  isActive() {
    return !this.activator || this.activator.active;
  }

  /**
   * Destroy the Core, clean up all DOM elements and event listeners.
   */
  destroy() {
    // unbind datasets
    this.setItems(null);
    this.setGroups(null);

    // remove all event listeners
    this.off();

    // stop checking for changed size
    this._stopAutoResize();

    // remove from DOM
    if (this.dom.root.parentNode) {
      this.dom.root.parentNode.removeChild(this.dom.root);
    }
    this.dom = null;

    // remove Activator
    if (this.activator) {
      this.activator.destroy();
      delete this.activator;
    }

    // cleanup hammer touch events
    for (const event in this.timelineListeners) {
      if (this.timelineListeners.hasOwnProperty(event)) {
        delete this.timelineListeners[event];
      }
    }
    this.timelineListeners = null;
    this.hammer && this.hammer.destroy();
    this.hammer = null;

    // give all components the opportunity to cleanup
    this.components.forEach(component => component.destroy());

    this.body = null;
  }

  /**
   * Set a custom time bar
   * @param {Date} time
   * @param {number} [id=undefined] Optional id of the custom time bar to be adjusted.
   */
  setCustomTime(time, id) {
    const customTimes = this.customTimes.filter(component => id === component.options.id);

    if (customTimes.length === 0) {
      throw new Error(`No custom time bar found with id ${JSON.stringify(id)}`)
    }

    if (customTimes.length > 0) {
      customTimes[0].setCustomTime(time);
    }
  }

  /**
   * Retrieve the current custom time.
   * @param {number} [id=undefined]    Id of the custom time bar.
   * @return {Date | undefined} customTime
   */
  getCustomTime(id) {
    const customTimes = this.customTimes.filter(component => component.options.id === id);

    if (customTimes.length === 0) {
      throw new Error(`No custom time bar found with id ${JSON.stringify(id)}`)
    }
    return customTimes[0].getCustomTime();
  }

  /**
   * Set a custom marker for the custom time bar.
   * @param {string} [title] Title of the custom marker.
   * @param {number} [id=undefined] Id of the custom marker.
   * @param {boolean} [editable=false] Make the custom marker editable.
   */
  setCustomTimeMarker(title, id, editable) {
    const customTimes = this.customTimes.filter(component => component.options.id === id);

    if (customTimes.length === 0) {
      throw new Error(`No custom time bar found with id ${JSON.stringify(id)}`)
    }
    if (customTimes.length > 0) {
      customTimes[0].setCustomMarker(title, editable);
    }
  }

  /**
   * Set a custom title for the custom time bar.
   * @param {string} [title] Custom title
   * @param {number} [id=undefined]    Id of the custom time bar.
   * @returns {*}
   */
  setCustomTimeTitle(title, id) {
    const customTimes = this.customTimes.filter(component => component.options.id === id);

    if (customTimes.length === 0) {
      throw new Error(`No custom time bar found with id ${JSON.stringify(id)}`)
    }
    if (customTimes.length > 0) {
      return customTimes[0].setCustomTitle(title);
    }
  }

  /**
   * Retrieve meta information from an event.
   * Should be overridden by classes extending Core
   * @param {Event} event
   * @return {Object} An object with related information.
   */
  getEventProperties(event) {
    return { event };
  }

  /**
   * Add custom vertical bar
   * @param {Date | string | number} [time]  A Date, unix timestamp, or
   *                                         ISO date string. Time point where
   *                                         the new bar should be placed.
   *                                         If not provided, `new Date()` will
   *                                         be used.
   * @param {number | string} [id=undefined] Id of the new bar. Optional
   * @return {number | string}               Returns the id of the new bar
   */
  addCustomTime(time, id) {
    const timestamp = time !== undefined
        ? util$3.convert(time, 'Date')
        : new Date();

    const exists = this.customTimes.some(customTime => customTime.options.id === id);
    if (exists) {
      throw new Error(`A custom time with id ${JSON.stringify(id)} already exists`);
    }

    const customTime = new CustomTime(this.body, util$3.extend({}, this.options, {
      time: timestamp,
      id,
      snap: this.itemSet ? this.itemSet.options.snap : this.options.snap
    }));

    this.customTimes.push(customTime);
    this.components.push(customTime);
    this._redraw();

    return id;
  }

  /**
   * Remove previously added custom bar
   * @param {int} id ID of the custom bar to be removed
   * [at]returns {boolean} True if the bar exists and is removed, false otherwise
   */
  removeCustomTime(id) {
    const customTimes = this.customTimes.filter(bar => bar.options.id === id);

    if (customTimes.length === 0) {
      throw new Error(`No custom time bar found with id ${JSON.stringify(id)}`)
    }

    customTimes.forEach(customTime => {
      this.customTimes.splice(this.customTimes.indexOf(customTime), 1);
      this.components.splice(this.components.indexOf(customTime), 1);
      customTime.destroy();
    });
  }

  /**
   * Get the id's of the currently visible items.
   * @returns {Array} The ids of the visible items
   */
  getVisibleItems() {
    return this.itemSet && this.itemSet.getVisibleItems() || [];
  }

  /**
   * Get the id's of the currently visible groups.
   * @returns {Array} The ids of the visible groups
   */
  getVisibleGroups() {
    return this.itemSet && this.itemSet.getVisibleGroups() || [];
  }

  /**
   * Set Core window such that it fits all items
   * @param {Object} [options]  Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   * @param {function} [callback] a callback funtion to be executed at the end of this function
   */
  fit(options, callback) {
    const range = this.getDataRange();

    // skip range set if there is no min and max date
    if (range.min === null && range.max === null) {
      return;
    }

    // apply a margin of 1% left and right of the data
    const interval = range.max - range.min;
    const min = new Date(range.min.valueOf() - interval * 0.01);
    const max = new Date(range.max.valueOf() + interval * 0.01);
    const animation = (options && options.animation !== undefined) ? options.animation : true;
    this.range.setRange(min, max, { animation }, callback);
  }

  /**
   * Calculate the data range of the items start and end dates
   * [at]returns {{min: [Date], max: [Date]}}
   * @protected
   */
  getDataRange() {
    // must be implemented by Timeline and Graph2d
    throw new Error('Cannot invoke abstract method getDataRange');
  }

  /**
   * Set the visible window. Both parameters are optional, you can change only
   * start or only end. Syntax:
   *
   *     TimeLine.setWindow(start, end)
   *     TimeLine.setWindow(start, end, options)
   *     TimeLine.setWindow(range)
   *
   * Where start and end can be a Date, number, or string, and range is an
   * object with properties start and end.
   *
   * @param {Date | number | string | Object} [start] Start date of visible window
   * @param {Date | number | string} [end]            End date of visible window
   * @param {Object} [options]  Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   * @param {function} [callback] a callback funtion to be executed at the end of this function
   */
  setWindow(start, end, options, callback) {
    if (typeof arguments[2] == "function") {
      callback = arguments[2];
      options = {};
    }
    let animation;
    let range;
    if (arguments.length == 1) {
      range = arguments[0];
      animation = (range.animation !== undefined) ? range.animation : true;
      this.range.setRange(range.start, range.end, { animation });
    }
    else if (arguments.length == 2 && typeof arguments[1] == "function") {
      range = arguments[0];
      callback = arguments[1];
      animation = (range.animation !== undefined) ? range.animation : true;
      this.range.setRange(range.start, range.end, { animation }, callback);
    }
    else {
      animation = (options && options.animation !== undefined) ? options.animation : true;
      this.range.setRange(start, end, { animation }, callback);
    }
  }

  /**
   * Move the window such that given time is centered on screen.
   * @param {Date | number | string} time
   * @param {Object} [options]  Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   * @param {function} [callback] a callback funtion to be executed at the end of this function
   */
  moveTo(time, options, callback) {
    if (typeof arguments[1] == "function") {
      callback = arguments[1];
      options = {};
    }
    const interval = this.range.end - this.range.start;
    const t = util$3.convert(time, 'Date').valueOf();

    const start = t - interval / 2;
    const end = t + interval / 2;
    const animation = (options && options.animation !== undefined) ? options.animation : true;

    this.range.setRange(start, end, { animation }, callback);
  }

  /**
   * Get the visible window
   * @return {{start: Date, end: Date}}   Visible range
   */
  getWindow() {
    const range = this.range.getRange();
    return {
      start: new Date(range.start),
      end: new Date(range.end)
    };
  }

  /**
   * Zoom in the window such that given time is centered on screen.
   * @param {number} percentage - must be between [0..1]
   * @param {Object} [options]  Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   * @param {function} [callback] a callback funtion to be executed at the end of this function
   */
  zoomIn(percentage, options, callback) {
    if (!percentage || percentage < 0 || percentage > 1) return;
    if (typeof arguments[1] == "function") {
      callback = arguments[1];
      options = {};
    }
    const range = this.getWindow();
    const start = range.start.valueOf();
    const end = range.end.valueOf();
    const interval = end - start;
    const newInterval = interval / (1 + percentage);
    const distance = (interval - newInterval) / 2;
    const newStart = start + distance;
    const newEnd = end - distance;

    this.setWindow(newStart, newEnd, options, callback);
  }

  /**
   * Zoom out the window such that given time is centered on screen.
   * @param {number} percentage - must be between [0..1]
   * @param {Object} [options]  Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   * @param {function} [callback] a callback funtion to be executed at the end of this function
   */
  zoomOut(percentage, options, callback) {
    if (!percentage || percentage < 0 || percentage > 1) return
    if (typeof arguments[1] == "function") {
      callback = arguments[1];
      options = {};
    }
    const range = this.getWindow();
    const start = range.start.valueOf();
    const end = range.end.valueOf();
    const interval = end - start;
    const newStart = start - interval * percentage / 2;
    const newEnd = end + interval * percentage / 2;

    this.setWindow(newStart, newEnd, options, callback);
  }

  /**
   * Force a redraw. Can be overridden by implementations of Core
   *
   * Note: this function will be overridden on construction with a trottled version
   */
  redraw() {
    this._redraw();
  }

  /**
   * Redraw for internal use. Redraws all components. See also the public
   * method redraw.
   * @protected
   */
  _redraw() {
    this.redrawCount++;
    const dom = this.dom;
    
    if (!dom || !dom.container || dom.root.offsetWidth == 0) return; // when destroyed, or invisible
    
    let resized = false;
    const options = this.options;
    const props = this.props;

    updateHiddenDates(this.options.moment, this.body, this.options.hiddenDates);

    // update class names
    if (options.orientation == 'top') {
      util$3.addClassName(dom.root, 'vis-top');
      util$3.removeClassName(dom.root, 'vis-bottom');
    }
    else {
      util$3.removeClassName(dom.root, 'vis-top');
      util$3.addClassName(dom.root, 'vis-bottom');
    }

    if (options.rtl) {
      util$3.addClassName(dom.root, 'vis-rtl');
      util$3.removeClassName(dom.root, 'vis-ltr');
    } else {
      util$3.addClassName(dom.root, 'vis-ltr');
      util$3.removeClassName(dom.root, 'vis-rtl');
    }

    // update root width and height options
    dom.root.style.maxHeight = util$3.option.asSize(options.maxHeight, '');
    dom.root.style.minHeight = util$3.option.asSize(options.minHeight, '');
    dom.root.style.width = util$3.option.asSize(options.width, '');
    const rootOffsetWidth = dom.root.offsetWidth;

    // calculate border widths
    props.border.left = 1;
    props.border.right = 1;
    props.border.top = 1;
    props.border.bottom = 1;

    // calculate the heights. If any of the side panels is empty, we set the height to
    // minus the border width, such that the border will be invisible
    props.center.height = dom.center.offsetHeight;
    props.left.height   = dom.left.offsetHeight;
    props.right.height  = dom.right.offsetHeight;
    props.top.height    = dom.top.clientHeight    || -props.border.top;
    props.bottom.height = Math.round(dom.bottom.getBoundingClientRect().height) || dom.bottom.clientHeight || -props.border.bottom;

    // TODO: compensate borders when any of the panels is empty.

    // apply auto height
    // TODO: only calculate autoHeight when needed (else we cause an extra reflow/repaint of the DOM)
    const contentHeight = Math.max(props.left.height, props.center.height, props.right.height);
    const autoHeight = props.top.height + contentHeight + props.bottom.height + props.border.top + props.border.bottom;
    dom.root.style.height = util$3.option.asSize(options.height, `${autoHeight}px`);

    // calculate heights of the content panels
    props.root.height = dom.root.offsetHeight;
    props.background.height = props.root.height;
    const containerHeight = props.root.height - props.top.height - props.bottom.height;
    props.centerContainer.height  = containerHeight;
    props.leftContainer.height    = containerHeight;
    props.rightContainer.height   = props.leftContainer.height;

    // calculate the widths of the panels
    props.root.width = rootOffsetWidth;
    props.background.width = props.root.width;

    if (!this.initialDrawDone) {
      props.scrollbarWidth = util$3.getScrollBarWidth();
    }

    const leftContainerClientWidth = dom.leftContainer.clientWidth;
    const rightContainerClientWidth = dom.rightContainer.clientWidth;

    if (options.verticalScroll) {
      if (options.rtl) {
        props.left.width = leftContainerClientWidth || -props.border.left;
        props.right.width = rightContainerClientWidth + props.scrollbarWidth || -props.border.right;
      } else {
        props.left.width = leftContainerClientWidth + props.scrollbarWidth || -props.border.left;
        props.right.width = rightContainerClientWidth || -props.border.right;
      }
    } else {
      props.left.width = leftContainerClientWidth  || -props.border.left;
      props.right.width = rightContainerClientWidth || -props.border.right;
    }

    this._setDOM();

    // update the scrollTop, feasible range for the offset can be changed
    // when the height of the Core or of the contents of the center changed
    let offset = this._updateScrollTop();

    // reposition the scrollable contents
    if (options.orientation.item != 'top') {
      offset += Math.max(props.centerContainer.height - props.center.height -
        props.border.top - props.border.bottom, 0);
    }
    dom.center.style.transform  = `translateY(${offset}px)`;

    // show shadows when vertical scrolling is available
    const visibilityTop = props.scrollTop == 0 ? 'hidden' : '';
    const visibilityBottom = props.scrollTop == props.scrollTopMin ? 'hidden' : '';
    dom.shadowTop.style.visibility          = visibilityTop;
    dom.shadowBottom.style.visibility       = visibilityBottom;
    dom.shadowTopLeft.style.visibility      = visibilityTop;
    dom.shadowBottomLeft.style.visibility   = visibilityBottom;
    dom.shadowTopRight.style.visibility     = visibilityTop;
    dom.shadowBottomRight.style.visibility  = visibilityBottom;

    if (options.verticalScroll) {
      dom.rightContainer.className = 'vis-panel vis-right vis-vertical-scroll';
      dom.leftContainer.className = 'vis-panel vis-left vis-vertical-scroll';

      dom.shadowTopRight.style.visibility     = "hidden";
      dom.shadowBottomRight.style.visibility  = "hidden";
      dom.shadowTopLeft.style.visibility      = "hidden";
      dom.shadowBottomLeft.style.visibility   = "hidden";

      dom.left.style.top    = '0px';
      dom.right.style.top   = '0px';
    }

    if (!options.verticalScroll ||  props.center.height < props.centerContainer.height) {
      dom.left.style.top    = `${offset}px`;
      dom.right.style.top   = `${offset}px`;
      dom.rightContainer.className = dom.rightContainer.className.replace(new RegExp('(?:^|\\s)'+ 'vis-vertical-scroll' + '(?:\\s|$)'), ' ');
      dom.leftContainer.className = dom.leftContainer.className.replace(new RegExp('(?:^|\\s)'+ 'vis-vertical-scroll' + '(?:\\s|$)'), ' ');
      props.left.width = leftContainerClientWidth  || -props.border.left;
      props.right.width = rightContainerClientWidth || -props.border.right;
      this._setDOM();
    }

    // enable/disable vertical panning
    const contentsOverflow = props.center.height > props.centerContainer.height;
    this.hammer.get('pan').set({
      direction: contentsOverflow ? Hammer$2.DIRECTION_ALL : Hammer$2.DIRECTION_HORIZONTAL
    });

    // set the long press time
    this.hammer.get('press').set({
      time: this.options.longSelectPressTime
    });

    // redraw all components
    this.components.forEach(component => {
      resized = component.redraw() || resized;
    });
    const MAX_REDRAW = 5;
    if (resized) {
      if (this.redrawCount < MAX_REDRAW) {
        this.body.emitter.emit('_change');
        return;
      }
      else {
        console.log('WARNING: infinite loop in redraw?');
      }
    } else {
      this.redrawCount = 0;
    }

    //Emit public 'changed' event for UI updates, see issue #1592
    this.body.emitter.emit("changed");
  }

  /**
   * sets the basic DOM components needed for the timeline\graph2d
   */
  _setDOM() {
    const props = this.props;
    const dom = this.dom;

    props.leftContainer.width = props.left.width;
    props.rightContainer.width = props.right.width;
    const centerWidth = props.root.width - props.left.width - props.right.width;
    props.center.width          = centerWidth;
    props.centerContainer.width = centerWidth;
    props.top.width             = centerWidth;
    props.bottom.width          = centerWidth;

    // resize the panels
    dom.background.style.height           = `${props.background.height}px`;
    dom.backgroundVertical.style.height   = `${props.background.height}px`;
    dom.backgroundHorizontal.style.height = `${props.centerContainer.height}px`;
    dom.centerContainer.style.height      = `${props.centerContainer.height}px`;
    dom.leftContainer.style.height        = `${props.leftContainer.height}px`;
    dom.rightContainer.style.height       = `${props.rightContainer.height}px`;

    dom.background.style.width            = `${props.background.width}px`;
    dom.backgroundVertical.style.width    = `${props.centerContainer.width}px`;
    dom.backgroundHorizontal.style.width  = `${props.background.width}px`;
    dom.centerContainer.style.width       = `${props.center.width}px`;
    dom.top.style.width                   = `${props.top.width}px`;
    dom.bottom.style.width                = `${props.bottom.width}px`;

    // reposition the panels
    dom.background.style.left           = '0';
    dom.background.style.top            = '0';
    dom.backgroundVertical.style.left   = `${props.left.width + props.border.left}px`;
    dom.backgroundVertical.style.top    = '0';
    dom.backgroundHorizontal.style.left = '0';
    dom.backgroundHorizontal.style.top  = `${props.top.height}px`;
    dom.centerContainer.style.left      = `${props.left.width}px`;
    dom.centerContainer.style.top       = `${props.top.height}px`;
    dom.leftContainer.style.left        = '0';
    dom.leftContainer.style.top         = `${props.top.height}px`;
    dom.rightContainer.style.left       = `${props.left.width + props.center.width}px`;
    dom.rightContainer.style.top        = `${props.top.height}px`;
    dom.top.style.left                  = `${props.left.width}px`;
    dom.top.style.top                   = '0';
    dom.bottom.style.left               = `${props.left.width}px`;
    dom.bottom.style.top                = `${props.top.height + props.centerContainer.height}px`;
    dom.center.style.left               = '0';
    dom.left.style.left                 = '0';
    dom.right.style.left                = '0';
  }

  /**
   * Set a current time. This can be used for example to ensure that a client's
   * time is synchronized with a shared server time.
   * Only applicable when option `showCurrentTime` is true.
   * @param {Date | string | number} time     A Date, unix timestamp, or
   *                                          ISO date string.
   */
  setCurrentTime(time) {
    if (!this.currentTime) {
      throw new Error('Option showCurrentTime must be true');
    }

    this.currentTime.setCurrentTime(time);
  }

  /**
   * Get the current time.
   * Only applicable when option `showCurrentTime` is true.
   * @return {Date} Returns the current time.
   */
  getCurrentTime() {
    if (!this.currentTime) {
      throw new Error('Option showCurrentTime must be true');
    }

    return this.currentTime.getCurrentTime();
  }

  /**
   * Convert a position on screen (pixels) to a datetime
   * @param {int}     x    Position on the screen in pixels
   * @return {Date}   time The datetime the corresponds with given position x
   * @protected
   * TODO: move this function to Range
   */
  _toTime(x) {
    return toTime(this, x, this.props.center.width);
  }

  /**
   * Convert a position on the global screen (pixels) to a datetime
   * @param {int}     x    Position on the screen in pixels
   * @return {Date}   time The datetime the corresponds with given position x
   * @protected
   * TODO: move this function to Range
   */
  _toGlobalTime(x) {
    return toTime(this, x, this.props.root.width);
    //var conversion = this.range.conversion(this.props.root.width);
    //return new Date(x / conversion.scale + conversion.offset);
  }

  /**
   * Convert a datetime (Date object) into a position on the screen
   * @param {Date}   time A date
   * @return {int}   x    The position on the screen in pixels which corresponds
   *                      with the given date.
   * @protected
   * TODO: move this function to Range
   */
  _toScreen(time) {
    return toScreen(this, time, this.props.center.width);
  }

  /**
   * Convert a datetime (Date object) into a position on the root
   * This is used to get the pixel density estimate for the screen, not the center panel
   * @param {Date}   time A date
   * @return {int}   x    The position on root in pixels which corresponds
   *                      with the given date.
   * @protected
   * TODO: move this function to Range
   */
  _toGlobalScreen(time) {
    return toScreen(this, time, this.props.root.width);
    //var conversion = this.range.conversion(this.props.root.width);
    //return (time.valueOf() - conversion.offset) * conversion.scale;
  }

  /**
   * Initialize watching when option autoResize is true
   * @private
   */
  _initAutoResize() {
    if (this.options.autoResize == true) {
      this._startAutoResize();
    }
    else {
      this._stopAutoResize();
    }
  }

  /**
   * Watch for changes in the size of the container. On resize, the Panel will
   * automatically redraw itself.
   * @private
   */
  _startAutoResize() {
    const me = this;

    this._stopAutoResize();

    this._onResize = () => {
      if (me.options.autoResize != true) {
        // stop watching when the option autoResize is changed to false
        me._stopAutoResize();
        return;
      }

      if (me.dom.root) {
        const rootOffsetHeight = me.dom.root.offsetHeight;
        const rootOffsetWidth = me.dom.root.offsetWidth;
        // check whether the frame is resized
        // Note: we compare offsetWidth here, not clientWidth. For some reason,
        // IE does not restore the clientWidth from 0 to the actual width after
        // changing the timeline's container display style from none to visible
        if ((rootOffsetWidth != me.props.lastWidth) ||
          (rootOffsetHeight != me.props.lastHeight)) {
          me.props.lastWidth = rootOffsetWidth;
          me.props.lastHeight = rootOffsetHeight;
          me.props.scrollbarWidth = util$3.getScrollBarWidth();

          me.body.emitter.emit('_change');
        }
      }
    };

    // add event listener to window resize
    util$3.addEventListener(window, 'resize', this._onResize);

    //Prevent initial unnecessary redraw
    if (me.dom.root) {
        me.props.lastWidth = me.dom.root.offsetWidth;
        me.props.lastHeight = me.dom.root.offsetHeight;
    }

    this.watchTimer = setInterval(this._onResize, 1000);
  }

  /**
   * Stop watching for a resize of the frame.
   * @private
   */
  _stopAutoResize() {
    if (this.watchTimer) {
      clearInterval(this.watchTimer);
      this.watchTimer = undefined;
    }

    // remove event listener on window.resize
    if (this._onResize) {
      util$3.removeEventListener(window, 'resize', this._onResize);
      this._onResize = null;
    }
  }

  /**
   * Start moving the timeline vertically
   * @param {Event} event
   * @private
   */
  _onTouch(event) {  // eslint-disable-line no-unused-vars
    this.touch.allowDragging = true;
    this.touch.initialScrollTop = this.props.scrollTop;
  }

  /**
   * Start moving the timeline vertically
   * @param {Event} event
   * @private
   */
  _onPinch(event) {  // eslint-disable-line no-unused-vars
    this.touch.allowDragging = false;
  }

  /**
   * Move the timeline vertically
   * @param {Event} event
   * @private
   */
  _onDrag(event) {
    if (!event) return
    // refuse to drag when we where pinching to prevent the timeline make a jump
    // when releasing the fingers in opposite order from the touch screen
    if (!this.touch.allowDragging) return;

    const delta = event.deltaY;

    const oldScrollTop = this._getScrollTop();
    const newScrollTop = this._setScrollTop(this.touch.initialScrollTop + delta);

    if (this.options.verticalScroll) {
      this.dom.left.parentNode.scrollTop = -this.props.scrollTop;
      this.dom.right.parentNode.scrollTop = -this.props.scrollTop;
    }

    if (newScrollTop != oldScrollTop) {
      this.emit("verticalDrag");
    }
  }

  /**
   * Apply a scrollTop
   * @param {number} scrollTop
   * @returns {number} scrollTop  Returns the applied scrollTop
   * @private
   */
  _setScrollTop(scrollTop) {
    this.props.scrollTop = scrollTop;
    this._updateScrollTop();
    return this.props.scrollTop;
  }

  /**
   * Update the current scrollTop when the height of  the containers has been changed
   * @returns {number} scrollTop  Returns the applied scrollTop
   * @private
   */
  _updateScrollTop() {
    // recalculate the scrollTopMin
    const scrollTopMin = Math.min(this.props.centerContainer.height - this.props.border.top - this.props.border.bottom - this.props.center.height, 0); // is negative or zero    
    if (scrollTopMin != this.props.scrollTopMin) {
      // in case of bottom orientation, change the scrollTop such that the contents
      // do not move relative to the time axis at the bottom
      if (this.options.orientation.item != 'top') {
        this.props.scrollTop += (scrollTopMin - this.props.scrollTopMin);
      }
      this.props.scrollTopMin = scrollTopMin;
    }

    // limit the scrollTop to the feasible scroll range
    if (this.props.scrollTop > 0) this.props.scrollTop = 0;
    if (this.props.scrollTop < scrollTopMin) this.props.scrollTop = scrollTopMin;

    if (this.options.verticalScroll) {
      this.dom.left.parentNode.scrollTop = -this.props.scrollTop;
      this.dom.right.parentNode.scrollTop = -this.props.scrollTop;
    }
    return this.props.scrollTop;
  }

  /**
   * Get the current scrollTop
   * @returns {number} scrollTop
   * @private
   */
  _getScrollTop() {
    return this.props.scrollTop;
  }

  /**
   * Load a configurator
   * [at]returns {Object}
   * @private
   */
  _createConfigurator() {
    throw new Error('Cannot invoke abstract method _createConfigurator');
  }
}

// turn Core into an event emitter
componentEmitter(Core.prototype);

/**
 * A current time bar
 */
class CurrentTime extends Component {
/**
 * @param {{range: Range, dom: Object, domProps: Object}} body
 * @param {Object} [options]        Available parameters:
 *                                  {Boolean} [showCurrentTime]
 *                                  {String}  [alignCurrentTime]
 * @constructor CurrentTime
 * @extends Component
 */
  constructor(body, options) {
    super();
    this.body = body;

    // default options
    this.defaultOptions = {
      rtl: false,
      showCurrentTime: true,
      alignCurrentTime: undefined,

      moment: moment$1,
      locales,
      locale: 'en'
    };
    this.options = util$3.extend({}, this.defaultOptions);
    this.setOptions(options);
    this.options.locales = util$3.extend({}, locales, this.options.locales);
    const defaultLocales = this.defaultOptions.locales[this.defaultOptions.locale];
    Object.keys(this.options.locales).forEach(locale => {
      this.options.locales[locale] = util$3.extend(
        {},
        defaultLocales,
        this.options.locales[locale]
      );
    });
    this.offset = 0;

    this._create();

  }

  /**
   * Create the HTML DOM for the current time bar
   * @private
   */
  _create() {
    const bar = document.createElement('div');
    bar.className = 'vis-current-time';
    bar.style.position = 'absolute';
    bar.style.top = '0px';
    bar.style.height = '100%';

    this.bar = bar;
  }

  /**
   * Destroy the CurrentTime bar
   */
  destroy() {
    this.options.showCurrentTime = false;
    this.redraw(); // will remove the bar from the DOM and stop refreshing

    this.body = null;
  }

  /**
   * Set options for the component. Options will be merged in current options.
   * @param {Object} options  Available parameters:
   *                          {boolean} [showCurrentTime]
   *                          {String}  [alignCurrentTime]
   */
  setOptions(options) {
    if (options) {
      // copy all options that we know
      util$3.selectiveExtend(['rtl', 'showCurrentTime', 'alignCurrentTime', 'moment', 'locale', 'locales'], this.options, options);
    }
  }

  /**
   * Repaint the component
   * @return {boolean} Returns true if the component is resized
   */
  redraw() {
    if (this.options.showCurrentTime) {
      const parent = this.body.dom.backgroundVertical;
      if (this.bar.parentNode != parent) {
        // attach to the dom
        if (this.bar.parentNode) {
          this.bar.parentNode.removeChild(this.bar);
        }
        parent.appendChild(this.bar);

        this.start();
      }

      let now = this.options.moment(Date.now() + this.offset);

      if (this.options.alignCurrentTime) {
        now = now.startOf(this.options.alignCurrentTime);
      }

      const x = this.body.util.toScreen(now);

      let locale = this.options.locales[this.options.locale];
      if (!locale) {
        if (!this.warned) {
          console.warn(`WARNING: options.locales['${this.options.locale}'] not found. See https://visjs.github.io/vis-timeline/docs/timeline/#Localization`);
          this.warned = true;
        }
        locale = this.options.locales['en']; // fall back on english when not available
      }
      let title = `${locale.current} ${locale.time}: ${now.format('dddd, MMMM Do YYYY, H:mm:ss')}`;
      title = title.charAt(0).toUpperCase() + title.substring(1);

      if (this.options.rtl) {
        this.bar.style.transform = `translateX(${x * -1}px)`;
      } else {
        this.bar.style.transform = `translateX(${x}px)`;
      }
      this.bar.title = title;
    }
    else {
      // remove the line from the DOM
      if (this.bar.parentNode) {
        this.bar.parentNode.removeChild(this.bar);
      }
      this.stop();
    }

    return false;
  }

  /**
   * Start auto refreshing the current time bar
   */
  start() {
    const me = this;

      /**
       *  Updates the current time.
       */
      function update () {
      me.stop();

      // determine interval to refresh
      const scale = me.body.range.conversion(me.body.domProps.center.width).scale;
      let interval = 1 / scale / 10;
      if (interval < 30)   interval = 30;
      if (interval > 1000) interval = 1000;

      me.redraw();
      me.body.emitter.emit('currentTimeTick');

      // start a renderTimer to adjust for the new time
      me.currentTimeTimer = setTimeout(update, interval);
    }

    update();
  }

  /**
   * Stop auto refreshing the current time bar
   */
  stop() {
    if (this.currentTimeTimer !== undefined) {
      clearTimeout(this.currentTimeTimer);
      delete this.currentTimeTimer;
    }
  }

  /**
   * Set a current time. This can be used for example to ensure that a client's
   * time is synchronized with a shared server time.
   * @param {Date | string | number} time     A Date, unix timestamp, or
   *                                          ISO date string.
   */
  setCurrentTime(time) {
    const t = util$3.convert(time, 'Date').valueOf();
    const now = Date.now();
    this.offset = t - now;
    this.redraw();
  }

  /**
   * Get the current time.
   * @return {Date} Returns the current time.
   */
  getCurrentTime() {
    return new Date(Date.now() + this.offset);
  }
}

// Utility functions for ordering and stacking of items
const EPSILON = 0.001; // used when checking collisions, to prevent round-off errors

/**
 * Order items by their start data
 * @param {Item[]} items
 */
function orderByStart(items) {
  items.sort((a, b) => a.data.start - b.data.start);
}

/**
 * Order items by their end date. If they have no end date, their start date
 * is used.
 * @param {Item[]} items
 */
function orderByEnd(items) {
  items.sort((a, b) => {
    const aTime = ('end' in a.data) ? a.data.end : a.data.start;
    const bTime = ('end' in b.data) ? b.data.end : b.data.start;

    return aTime - bTime;
  });
}

/**
 * Adjust vertical positions of the items such that they don't overlap each
 * other.
 * @param {Item[]} items
 *            All visible items
 * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
 *            Margins between items and between items and the axis.
 * @param {boolean} [force=false]
 *            If true, all items will be repositioned. If false (default), only
 *            items having a top===null will be re-stacked
 * @param {function} shouldBailItemsRedrawFunction
 *            bailing function
 * @return {boolean} shouldBail
 */
function stack(items, margin, force, shouldBailItemsRedrawFunction) {
  if (force) {
    // reset top position of all items
    for (var i = 0; i < items.length; i++) {
      items[i].top = null;
    }
  }

  // calculate new, non-overlapping positions
  for (var i = 0; i < items.length; i++) {  // eslint-disable-line no-redeclare
    const item = items[i];
    if (item.stack && item.top === null) {
      // initialize top position
      item.top = margin.axis;
      var shouldBail = false;

      do {
        // TODO: optimize checking for overlap. when there is a gap without items,
        //       you only need to check for items from the next item on, not from zero
        var collidingItem = null;
        for (let j = 0, jj = items.length; j < jj; j++) {
          const other = items[j];
          shouldBail = shouldBailItemsRedrawFunction() || false;

          if (shouldBail) { return true; }

          if (other.top !== null && other !== item && other.stack && collision(item, other, margin.item, other.options.rtl)) {
            collidingItem = other;
            break;
          }
        }

        if (collidingItem != null) {
          // There is a collision. Reposition the items above the colliding element
          item.top = collidingItem.top + collidingItem.height + margin.item.vertical;
        }
      } while (collidingItem);
    }
  }
  return shouldBail;
}

/**
 * Adjust vertical positions of the items within a single subgroup such that they
 * don't overlap each other.
 * @param {Item[]} items
 *            All items withina subgroup
 * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
 *            Margins between items and between items and the axis.
 * @param {subgroup} subgroup
 *            The subgroup that is being stacked
 */
function substack(items, margin, subgroup) {
  for (var i = 0; i < items.length; i++) {
    items[i].top = null;
  }

  // Set the initial height
  let subgroupHeight = subgroup.height;

  // calculate new, non-overlapping positions
  for (i = 0; i < items.length; i++) {
    const item = items[i];

    if (item.stack && item.top === null) {
      // initialize top position
      item.top = item.baseTop;//margin.axis + item.baseTop;

      do {
        // TODO: optimize checking for overlap. when there is a gap without items,
        //       you only need to check for items from the next item on, not from zero
        var collidingItem = null;
        for (let j = 0, jj = items.length; j < jj; j++) {
          const other = items[j];
          if (other.top !== null && other !== item /*&& other.stack*/ && collision(item, other, margin.item, other.options.rtl)) {
            collidingItem = other;
            break;
          }
        }

        if (collidingItem != null) {
          // There is a collision. Reposition the items above the colliding element
          item.top = collidingItem.top + collidingItem.height + margin.item.vertical;// + item.baseTop;
        }

        if (item.top + item.height > subgroupHeight) {
          subgroupHeight = item.top + item.height;
        }
      } while (collidingItem);
    }
  }

  // Set the new height
  subgroup.height = subgroupHeight - subgroup.top + 0.5 * margin.item.vertical;
}

/**
 * Adjust vertical positions of the items without stacking them
 * @param {Item[]} items
 *            All visible items
 * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
 *            Margins between items and between items and the axis.
 * @param {subgroups[]} subgroups
 *            All subgroups
 * @param {boolean} isStackSubgroups
 */
function nostack(items, margin, subgroups, isStackSubgroups) {
  for (let i = 0; i < items.length; i++) {
    if (items[i].data.subgroup == undefined) {
      items[i].top = margin.item.vertical;
    } else if (items[i].data.subgroup !== undefined && isStackSubgroups) {
      let newTop = 0;
      for (const subgroup in subgroups) {
        if (subgroups.hasOwnProperty(subgroup)) {
          if (subgroups[subgroup].visible == true && subgroups[subgroup].index < subgroups[items[i].data.subgroup].index) {
            newTop += subgroups[subgroup].height;
            subgroups[items[i].data.subgroup].top = newTop;
          }
        }
      }
      items[i].top = newTop + 0.5 * margin.item.vertical;
    }
  }
  if (!isStackSubgroups) {
    stackSubgroups(items, margin, subgroups);
  }
}

/**
 * Adjust vertical positions of the subgroups such that they don't overlap each
 * other.
 * @param {Array.<timeline.Item>} items
 * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin Margins between items and between items and the axis.
 * @param {subgroups[]} subgroups
 *            All subgroups
 */
function stackSubgroups(items, margin, subgroups) {
  for (const subgroup in subgroups) {
    if (subgroups.hasOwnProperty(subgroup)) {


      subgroups[subgroup].top = 0;
      do {
        // TODO: optimize checking for overlap. when there is a gap without items,
        //       you only need to check for items from the next item on, not from zero
        var collidingItem = null;
        for (const otherSubgroup in subgroups) {
          if (subgroups[otherSubgroup].top !== null && otherSubgroup !== subgroup && subgroups[subgroup].index > subgroups[otherSubgroup].index && collisionByTimes(subgroups[subgroup], subgroups[otherSubgroup])) {
            collidingItem = subgroups[otherSubgroup];
            break;
          }
        }

        if (collidingItem != null) {
          // There is a collision. Reposition the subgroups above the colliding element
          subgroups[subgroup].top = collidingItem.top + collidingItem.height;
        }
      } while (collidingItem);
    }
  }
  for (let i = 0; i < items.length; i++) {
    if (items[i].data.subgroup !== undefined) {
      items[i].top = subgroups[items[i].data.subgroup].top + 0.5 * margin.item.vertical;
    }
  }
}

/**
 * Adjust vertical positions of the subgroups such that they don't overlap each
 * other, then stacks the contents of each subgroup individually.
 * @param {Item[]} subgroupItems
 *            All the items in a subgroup
 * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
 *            Margins between items and between items and the axis.
 * @param {subgroups[]} subgroups
 *            All subgroups
 */
function stackSubgroupsWithInnerStack(subgroupItems, margin, subgroups) {
  let doSubStack = false;

  // Run subgroups in their order (if any)
  const subgroupOrder = [];

  for(var subgroup in subgroups) {
    if (subgroups[subgroup].hasOwnProperty("index")) {
      subgroupOrder[subgroups[subgroup].index] = subgroup;
    }
    else {
      subgroupOrder.push(subgroup);
    }
  }

  for(let j = 0; j < subgroupOrder.length; j++) {
    subgroup = subgroupOrder[j];
    if (subgroups.hasOwnProperty(subgroup)) {

      doSubStack = doSubStack || subgroups[subgroup].stack;
      subgroups[subgroup].top = 0;

      for (const otherSubgroup in subgroups) {
        if (subgroups[otherSubgroup].visible && subgroups[subgroup].index > subgroups[otherSubgroup].index) {
          subgroups[subgroup].top += subgroups[otherSubgroup].height;
        }
      }

      const items = subgroupItems[subgroup];
      for(let i = 0; i < items.length; i++) {
        if (items[i].data.subgroup !== undefined) {
          items[i].top = subgroups[items[i].data.subgroup].top + 0.5 * margin.item.vertical;

          if (subgroups[subgroup].stack) {
            items[i].baseTop = items[i].top;
          }
        }
      }

      if (doSubStack && subgroups[subgroup].stack) {
        substack(subgroupItems[subgroup], margin, subgroups[subgroup]);
      }
    }
  }
}

/**
 * Test if the two provided items collide
 * The items must have parameters left, width, top, and height.
 * @param {Item} a          The first item
 * @param {Item} b          The second item
 * @param {{horizontal: number, vertical: number}} margin
 *                          An object containing a horizontal and vertical
 *                          minimum required margin.
 * @param {boolean} rtl
 * @return {boolean}        true if a and b collide, else false
 */
function collision(a, b, margin, rtl) {
  if (rtl) {
    return  ((a.right - margin.horizontal + EPSILON)  < (b.right + b.width) &&
    (a.right + a.width + margin.horizontal - EPSILON) > b.right &&
    (a.top - margin.vertical + EPSILON)              < (b.top + b.height) &&
    (a.top + a.height + margin.vertical - EPSILON)   > b.top);
  } else {
    return ((a.left - margin.horizontal + EPSILON)   < (b.left + b.width) &&
    (a.left + a.width + margin.horizontal - EPSILON) > b.left &&
    (a.top - margin.vertical + EPSILON)              < (b.top + b.height) &&
    (a.top + a.height + margin.vertical - EPSILON)   > b.top);
  }
}

/**
 * Test if the two provided objects collide
 * The objects must have parameters start, end, top, and height.
 * @param {Object} a          The first Object
 * @param {Object} b          The second Object
 * @return {boolean}        true if a and b collide, else false
 */
function collisionByTimes(a, b) {

  // Check for overlap by time and height. Abutting is OK and
  // not considered a collision while overlap is considered a collision.
  const timeOverlap = a.start < b.end && a.end > b.start;
  const heightOverlap = a.top < (b.top + b.height) && (a.top + a.height) > b.top;
  return timeOverlap && heightOverlap;
}

const UNGROUPED = '__ungrouped__';   // reserved group id for ungrouped items
const BACKGROUND = '__background__'; // reserved group id for background items without group

const ReservedGroupIds = {
  UNGROUPED,
  BACKGROUND
};


/**
 * @constructor Group
 */
class Group {
  /**
 * @param {number | string} groupId
 * @param {Object} data
 * @param {ItemSet} itemSet
 * @constructor Group
 */
  constructor(groupId, data, itemSet) {
    this.groupId = groupId;
    this.subgroups = {};
    this.subgroupStack = {};
    this.subgroupStackAll = false;
    this.subgroupVisibility = {};
    this.doInnerStack = false;
    this.shouldBailStackItems = false;
    this.subgroupIndex = 0;
    this.subgroupOrderer = data && data.subgroupOrder;
    this.itemSet = itemSet;
    this.isVisible = null;
    this.stackDirty = true; // if true, items will be restacked on next redraw

    // This is a stack of functions (`() => void`) that will be executed before
    // the instance is disposed off (method `dispose`). Anything that needs to
    // be manually disposed off before garbage collection happens (or so that
    // garbage collection can happen) should be added to this stack.
    this._disposeCallbacks = [];

    if (data && data.nestedGroups) {
      this.nestedGroups = data.nestedGroups;
      if (data.showNested == false) {
        this.showNested = false;
      } else {
        this.showNested = true;
      }
    }

    if (data && data.subgroupStack) {
      if (typeof data.subgroupStack === "boolean") {
        this.doInnerStack = data.subgroupStack;
        this.subgroupStackAll = data.subgroupStack;
      }
      else {
        // We might be doing stacking on specific sub groups, but only
        // if at least one is set to do stacking
        for(const key in data.subgroupStack) {
          this.subgroupStack[key] = data.subgroupStack[key];
          this.doInnerStack = this.doInnerStack || data.subgroupStack[key];
        }
      }
    }

    if (data && data.heightMode) {
      this.heightMode = data.heightMode;
    } else {
      this.heightMode = itemSet.options.groupHeightMode;
    }

    this.nestedInGroup = null;

    this.dom = {};
    this.props = {
      label: {
        width: 0,
        height: 0
      }
    };
    this.className = null;

    this.items = {};        // items filtered by groupId of this group
    this.visibleItems = []; // items currently visible in window
    this.itemsInRange = []; // items currently in range
    this.orderedItems = {
      byStart: [],
      byEnd: []
    };
    this.checkRangedItems = false; // needed to refresh the ranged items if the window is programatically changed with NO overlap.

    const handleCheckRangedItems = () => {
      this.checkRangedItems = true;
    };
    this.itemSet.body.emitter.on("checkRangedItems", handleCheckRangedItems);
    this._disposeCallbacks.push(() => {
      this.itemSet.body.emitter.off("checkRangedItems", handleCheckRangedItems);
    });

    this._create();

    this.setData(data);
  }

  /**
   * Create DOM elements for the group
   * @private
   */
  _create() {
    const label = document.createElement('div');
    if (this.itemSet.options.groupEditable.order) {
      label.className = 'vis-label draggable';
    } else {
      label.className = 'vis-label';
    }
    this.dom.label = label;

    const inner = document.createElement('div');
    inner.className = 'vis-inner';
    label.appendChild(inner);
    this.dom.inner = inner;

    const foreground = document.createElement('div');
    foreground.className = 'vis-group';
    foreground['vis-group'] = this;
    this.dom.foreground = foreground;

    this.dom.background = document.createElement('div');
    this.dom.background.className = 'vis-group';

    this.dom.axis = document.createElement('div');
    this.dom.axis.className = 'vis-group';

    // create a hidden marker to detect when the Timelines container is attached
    // to the DOM, or the style of a parent of the Timeline is changed from
    // display:none is changed to visible.
    this.dom.marker = document.createElement('div');
    this.dom.marker.style.visibility = 'hidden';
    this.dom.marker.style.position = 'absolute';
    this.dom.marker.innerHTML = '';
    this.dom.background.appendChild(this.dom.marker);
  }

  /**
   * Set the group data for this group
   * @param {Object} data   Group data, can contain properties content and className
   */
  setData(data) {
    if (this.itemSet.groupTouchParams.isDragging) return;

    // update contents
    let content;
    let templateFunction;

    if (data && data.subgroupVisibility) {
      for (const key in data.subgroupVisibility) {
        this.subgroupVisibility[key] = data.subgroupVisibility[key];
      }
    }

    if (this.itemSet.options && this.itemSet.options.groupTemplate) {
      templateFunction = this.itemSet.options.groupTemplate.bind(this);
      content = templateFunction(data, this.dom.inner);
    } else {
      content = data && data.content;
    }

    if (content instanceof Element) {
      while (this.dom.inner.firstChild) {
        this.dom.inner.removeChild(this.dom.inner.firstChild);
      }
      this.dom.inner.appendChild(content);
    } else if (content instanceof Object && content.isReactComponent) ; else if (content instanceof Object) {
      templateFunction(data, this.dom.inner);
    } else if (content !== undefined && content !== null) {
      this.dom.inner.innerHTML = util$3.xss(content);
    } else {
      this.dom.inner.innerHTML = util$3.xss(this.groupId || ''); // groupId can be null
    }

    // update title
    this.dom.label.title = data && data.title || '';
    if (!this.dom.inner.firstChild) {
      util$3.addClassName(this.dom.inner, 'vis-hidden');
    }
    else {
      util$3.removeClassName(this.dom.inner, 'vis-hidden');
    }

    if (data && data.nestedGroups) {
      if (!this.nestedGroups || this.nestedGroups != data.nestedGroups) {
        this.nestedGroups = data.nestedGroups;
      }

      if (data.showNested !== undefined || this.showNested === undefined) {
        if (data.showNested == false) {
          this.showNested = false;
        } else {
          this.showNested = true;
        }
      }

      util$3.addClassName(this.dom.label, 'vis-nesting-group');
      if (this.showNested) {
        util$3.removeClassName(this.dom.label, 'collapsed');
        util$3.addClassName(this.dom.label, 'expanded');
      } else {
        util$3.removeClassName(this.dom.label, 'expanded');
        util$3.addClassName(this.dom.label, 'collapsed');
      }
    } else if (this.nestedGroups) {
      this.nestedGroups = null;
      util$3.removeClassName(this.dom.label, 'collapsed');
      util$3.removeClassName(this.dom.label, 'expanded');
      util$3.removeClassName(this.dom.label, 'vis-nesting-group');
    }

    if (data && (data.treeLevel|| data.nestedInGroup)) {
      util$3.addClassName(this.dom.label, 'vis-nested-group');
      if (data.treeLevel) {
        util$3.addClassName(this.dom.label, 'vis-group-level-' + data.treeLevel);
      } else {
        // Nesting level is unknown, but we're sure it's at least 1
        util$3.addClassName(this.dom.label, 'vis-group-level-unknown-but-gte1');
      }
    } else {
      util$3.addClassName(this.dom.label, 'vis-group-level-0');
    }
    
    // update className
    const className = data && data.className || null;
    if (className != this.className) {
      if (this.className) {
        util$3.removeClassName(this.dom.label, this.className);
        util$3.removeClassName(this.dom.foreground, this.className);
        util$3.removeClassName(this.dom.background, this.className);
        util$3.removeClassName(this.dom.axis, this.className);
      }
      util$3.addClassName(this.dom.label, className);
      util$3.addClassName(this.dom.foreground, className);
      util$3.addClassName(this.dom.background, className);
      util$3.addClassName(this.dom.axis, className);
      this.className = className;
    }

    // update style
    if (this.style) {
      util$3.removeCssText(this.dom.label, this.style);
      this.style = null;
    }
    if (data && data.style) {
      util$3.addCssText(this.dom.label, data.style);
      this.style = data.style;
    }
  }

  /**
   * Get the width of the group label
   * @return {number} width
   */
  getLabelWidth() {
    return this.props.label.width;
  }

  /**
   * check if group has had an initial height hange
   * @returns {boolean} 
   */
  _didMarkerHeightChange() {
    const markerHeight = this.dom.marker.clientHeight;
    if (markerHeight != this.lastMarkerHeight) {
      this.lastMarkerHeight = markerHeight;
      const redrawQueue = {};
      let redrawQueueLength = 0;

      util$3.forEach(this.items, (item, key) => {
        item.dirty = true;
        if (item.displayed) {
          const returnQueue = true;
          redrawQueue[key] = item.redraw(returnQueue);
          redrawQueueLength = redrawQueue[key].length;
        }
      });

      const needRedraw = redrawQueueLength > 0;
      if (needRedraw) {
        // redraw all regular items
        for (let i = 0; i < redrawQueueLength; i++) {
          util$3.forEach(redrawQueue, fns => {
            fns[i]();
          });
        }
      }
      return true;
    } else {
      return false;
    }
  }

  /**
   * calculate group dimentions and position
   * @param {number} pixels
   */
  _calculateGroupSizeAndPosition() {
    const { offsetTop, offsetLeft, offsetWidth } = this.dom.foreground;
    this.top = offsetTop;
    this.right = offsetLeft;
    this.width = offsetWidth;
  }

  /**
   * checks if should bail redraw of items
   * @returns {boolean} should bail 
   */
  _shouldBailItemsRedraw() {
    const me = this;
    const timeoutOptions = this.itemSet.options.onTimeout;
    const bailOptions = {
      relativeBailingTime: this.itemSet.itemsSettingTime,
      bailTimeMs: timeoutOptions && timeoutOptions.timeoutMs,
      userBailFunction: timeoutOptions && timeoutOptions.callback,
      shouldBailStackItems: this.shouldBailStackItems
    };
    let bail = null;
    if (!this.itemSet.initialDrawDone) {
      if (bailOptions.shouldBailStackItems) { return true; }
      if (Math.abs(Date.now() - new Date(bailOptions.relativeBailingTime)) > bailOptions.bailTimeMs) {
        if (bailOptions.userBailFunction && this.itemSet.userContinueNotBail == null) {
          bailOptions.userBailFunction(didUserContinue => {
            me.itemSet.userContinueNotBail = didUserContinue;
            bail = !didUserContinue;
          });
        } else if (me.itemSet.userContinueNotBail == false) {
          bail = true;
        } else {
          bail = false;
        }
      }
    }

    return bail;
  }

  /**
   * redraws items
   * @param {boolean} forceRestack
   * @param {boolean} lastIsVisible
   * @param {number} margin
   * @param {object} range
   * @private
   */
  _redrawItems(forceRestack, lastIsVisible, margin, range) {
    const restack = forceRestack || this.stackDirty || this.isVisible && !lastIsVisible;

    // if restacking, reposition visible items vertically
    if (restack) {
      const orderedItems = {
        byEnd: this.orderedItems.byEnd.filter(item => !item.isCluster),
        byStart: this.orderedItems.byStart.filter(item => !item.isCluster)
      };

      const orderedClusters = {
        byEnd: [...new Set(this.orderedItems.byEnd.map(item => item.cluster).filter(item => !!item))],
        byStart: [...new Set(this.orderedItems.byStart.map(item => item.cluster).filter(item => !!item))],
      };

     /**
     * Get all visible items in range
     * @return {array} items
     */
      const getVisibleItems = () => {
        const visibleItems = this._updateItemsInRange(orderedItems, this.visibleItems.filter(item => !item.isCluster), range);
        const visibleClusters = this._updateClustersInRange(orderedClusters, this.visibleItems.filter(item => item.isCluster), range);
        return [...visibleItems, ...visibleClusters];
      };

      /**
       * Get visible items grouped by subgroup
       * @param {function} orderFn An optional function to order items inside the subgroups
       * @return {Object}
       */
      const getVisibleItemsGroupedBySubgroup = orderFn => {
        let visibleSubgroupsItems = {};
        for (const subgroup in this.subgroups) {
          const items = this.visibleItems.filter(item => item.data.subgroup === subgroup);
          visibleSubgroupsItems[subgroup] = orderFn ? items.sort((a, b) => orderFn(a.data, b.data)) : items;
        }
        return visibleSubgroupsItems;
      };

      if (typeof this.itemSet.options.order === 'function') {
        // a custom order function
        //show all items
        const me = this;
        if (this.doInnerStack && this.itemSet.options.stackSubgroups) {
          // Order the items within each subgroup
          const visibleSubgroupsItems = getVisibleItemsGroupedBySubgroup(this.itemSet.options.order);
          stackSubgroupsWithInnerStack(visibleSubgroupsItems, margin, this.subgroups);
          this.visibleItems = getVisibleItems();
          this._updateSubGroupHeights(margin);
        }
        else {
          this.visibleItems = getVisibleItems();
          this._updateSubGroupHeights(margin);
          // order all items and force a restacking
           // order all items outside clusters and force a restacking
          const customOrderedItems = this.visibleItems
                                  .slice()
                                  .filter(item => item.isCluster || (!item.isCluster && !item.cluster))
                                  .sort((a, b) => {
                                      return me.itemSet.options.order(a.data, b.data);
                                  });
          this.shouldBailStackItems = stack(customOrderedItems, margin, true, this._shouldBailItemsRedraw.bind(this));
        }
      } else {
        // no custom order function, lazy stacking
        this.visibleItems = getVisibleItems();
        this._updateSubGroupHeights(margin);

        if (this.itemSet.options.stack) {
          if (this.doInnerStack && this.itemSet.options.stackSubgroups) {
            const visibleSubgroupsItems = getVisibleItemsGroupedBySubgroup();
            stackSubgroupsWithInnerStack(visibleSubgroupsItems, margin, this.subgroups);
          }
          else {
            // TODO: ugly way to access options...
            this.shouldBailStackItems = stack(this.visibleItems, margin, true, this._shouldBailItemsRedraw.bind(this));
          }
        } else {
          // no stacking
          nostack(this.visibleItems, margin, this.subgroups, this.itemSet.options.stackSubgroups);
        }
      }

      for (let i = 0; i < this.visibleItems.length; i++) {
        this.visibleItems[i].repositionX();
        if (this.subgroupVisibility[this.visibleItems[i].data.subgroup] !== undefined) {
          if (!this.subgroupVisibility[this.visibleItems[i].data.subgroup]) {
            this.visibleItems[i].hide();
          }
        }
      }

      if (this.itemSet.options.cluster) {
        util$3.forEach(this.items, item => {
          if (item.cluster && item.displayed) {
            item.hide();
          }
        });
      }

      if (this.shouldBailStackItems) {
        this.itemSet.body.emitter.emit('destroyTimeline');
      }
      this.stackDirty = false;
    }
  }

  /**
   * check if group resized
   * @param {boolean} resized
   * @param {number} height
   * @return {boolean} did resize
   */
  _didResize(resized, height) {
    resized = util$3.updateProperty(this, 'height', height) || resized;
    // recalculate size of label
    const labelWidth = this.dom.inner.clientWidth;
    const labelHeight = this.dom.inner.clientHeight;
    resized = util$3.updateProperty(this.props.label, 'width', labelWidth) || resized;
    resized = util$3.updateProperty(this.props.label, 'height', labelHeight) || resized;
    return resized;
  }

  /**
   * apply group height
   * @param {number} height
   */
  _applyGroupHeight(height) {
    this.dom.background.style.height = `${height}px`;
    this.dom.foreground.style.height = `${height}px`;
    this.dom.label.style.height = `${height}px`;
  }

  /**
   * update vertical position of items after they are re-stacked and the height of the group is calculated
   * @param {number} margin
   */
  _updateItemsVerticalPosition(margin) {
    for (let i = 0, ii = this.visibleItems.length; i < ii; i++) {
      const item = this.visibleItems[i];
      item.repositionY(margin);
      if (!this.isVisible && this.groupId != ReservedGroupIds.BACKGROUND) {
        if (item.displayed) item.hide();
      }
    }
  }

  /**
   * Repaint this group
   * @param {{start: number, end: number}} range
   * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
   * @param {boolean} [forceRestack=false]  Force restacking of all items
   * @param {boolean} [returnQueue=false]  return the queue or if the group resized
   * @return {boolean} Returns true if the group is resized or the redraw queue if returnQueue=true
   */
  redraw(range, margin, forceRestack, returnQueue) {
    let resized = false;
    const lastIsVisible = this.isVisible;
    let height;

    const queue = [
      () => {
        forceRestack = this._didMarkerHeightChange.call(this) || forceRestack;
      },
      
      // recalculate the height of the subgroups
      this._updateSubGroupHeights.bind(this, margin),

      // calculate actual size and position
      this._calculateGroupSizeAndPosition.bind(this),

      () => {
        this.isVisible = this._isGroupVisible.bind(this)(range, margin);
      },
      
      () => {
        this._redrawItems.bind(this)(forceRestack, lastIsVisible, margin, range);
      },

      // update subgroups
      this._updateSubgroupsSizes.bind(this),

      () => {
        height = this._calculateHeight.bind(this)(margin);
      },

      // calculate actual size and position again
      this._calculateGroupSizeAndPosition.bind(this),

      () => {
        resized = this._didResize.bind(this)(resized, height);
      },

      () => {
        this._applyGroupHeight.bind(this)(height);
      },

      () => {
        this._updateItemsVerticalPosition.bind(this)(margin);
      },

      (() => {
        if (!this.isVisible && this.height) {
          resized = false;
        }
        return resized
      }).bind(this)
    ];

    if (returnQueue) {
      return queue;
    } else {
      let result;
      queue.forEach(fn => {
        result = fn();
      });
      return result;
    }
  }

  /**
   * recalculate the height of the subgroups
   *
   * @param {{item: timeline.Item}} margin
   * @private
   */
  _updateSubGroupHeights(margin) {
    if (Object.keys(this.subgroups).length > 0) {
      const me = this;

      this._resetSubgroups();

      util$3.forEach(this.visibleItems, item => {
        if (item.data.subgroup !== undefined) {
          me.subgroups[item.data.subgroup].height = Math.max(me.subgroups[item.data.subgroup].height, item.height + margin.item.vertical);
          me.subgroups[item.data.subgroup].visible = typeof this.subgroupVisibility[item.data.subgroup] === 'undefined' ? true : Boolean(this.subgroupVisibility[item.data.subgroup]);
        }
      });
    }
  }

  /**
   * check if group is visible
   *
   * @param {timeline.Range} range
   * @param {{axis: timeline.DataAxis}} margin
   * @returns {boolean} is visible
   * @private
   */
  _isGroupVisible(range, margin) {
    return (this.top <= range.body.domProps.centerContainer.height - range.body.domProps.scrollTop + margin.axis)
    && (this.top + this.height + margin.axis >= - range.body.domProps.scrollTop);
  }

  /**
   * recalculate the height of the group
   * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
   * @returns {number} Returns the height
   * @private
   */
  _calculateHeight(margin) {
    // recalculate the height of the group
    let height;

    let items;

    if (this.heightMode === 'fixed') {
      items = util$3.toArray(this.items);
    } else {
      // default or 'auto'
      items = this.visibleItems;
    }

    if (items.length > 0) {
      let min = items[0].top;
      let max = items[0].top + items[0].height;
      util$3.forEach(items, item => {
        min = Math.min(min, item.top);
        max = Math.max(max, (item.top + item.height));
      });
      if (min > margin.axis) {
        // there is an empty gap between the lowest item and the axis
        const offset = min - margin.axis;
        max -= offset;
        util$3.forEach(items, item => {
          item.top -= offset;
        });
      }
      height = Math.ceil(max + margin.item.vertical / 2);
      if (this.heightMode !== "fitItems") {
        height = Math.max(height, this.props.label.height);
      }
    }
    else {
      height =  this.props.label.height;
    }
    return height;
  }

  /**
   * Show this group: attach to the DOM
   */
  show() {
    if (!this.dom.label.parentNode) {
      this.itemSet.dom.labelSet.appendChild(this.dom.label);
    }

    if (!this.dom.foreground.parentNode) {
      this.itemSet.dom.foreground.appendChild(this.dom.foreground);
    }

    if (!this.dom.background.parentNode) {
      this.itemSet.dom.background.appendChild(this.dom.background);
    }

    if (!this.dom.axis.parentNode) {
      this.itemSet.dom.axis.appendChild(this.dom.axis);
    }
  }

  /**
   * Hide this group: remove from the DOM
   */
  hide() {
    const label = this.dom.label;
    if (label.parentNode) {
      label.parentNode.removeChild(label);
    }

    const foreground = this.dom.foreground;
    if (foreground.parentNode) {
      foreground.parentNode.removeChild(foreground);
    }

    const background = this.dom.background;
    if (background.parentNode) {
      background.parentNode.removeChild(background);
    }

    const axis = this.dom.axis;
    if (axis.parentNode) {
      axis.parentNode.removeChild(axis);
    }
  }

  /**
   * Add an item to the group
   * @param {Item} item
   */
  add(item) {
    this.items[item.id] = item;
    item.setParent(this);
    this.stackDirty = true;
    // add to
    if (item.data.subgroup !== undefined) {
      this._addToSubgroup(item);
      this.orderSubgroups();
    }

    if (!this.visibleItems.includes(item)) {
      const range = this.itemSet.body.range; // TODO: not nice accessing the range like this
      this._checkIfVisible(item, this.visibleItems, range);
    }
  }

  /**
   * add item to subgroup
   * @param {object} item
   * @param {string} subgroupId
   */
  _addToSubgroup(item, subgroupId=item.data.subgroup) {
    if (subgroupId != undefined && this.subgroups[subgroupId] === undefined) {
      this.subgroups[subgroupId] = {
        height: 0,
        top: 0,
        start: item.data.start,
        end: item.data.end || item.data.start,
        visible: false,
        index: this.subgroupIndex,
        items: [],
        stack: this.subgroupStackAll || this.subgroupStack[subgroupId] || false
      };
      this.subgroupIndex++;
    }


    if (new Date(item.data.start) < new Date(this.subgroups[subgroupId].start)) {
      this.subgroups[subgroupId].start = item.data.start;
    }

    const itemEnd = item.data.end || item.data.start;
    if (new Date(itemEnd) > new Date(this.subgroups[subgroupId].end)) {
      this.subgroups[subgroupId].end = itemEnd;
    }

    this.subgroups[subgroupId].items.push(item);
  }

  /**
   * update subgroup sizes
   */
  _updateSubgroupsSizes() {
    const me = this;
    if (me.subgroups) {
      for (const subgroup in me.subgroups) {
        const initialEnd = me.subgroups[subgroup].items[0].data.end || me.subgroups[subgroup].items[0].data.start;
        let newStart = me.subgroups[subgroup].items[0].data.start;
        let newEnd = initialEnd - 1;

        me.subgroups[subgroup].items.forEach(item => {
          if (new Date(item.data.start) < new Date(newStart)) {
            newStart = item.data.start;
          }

          const itemEnd = item.data.end || item.data.start;
          if (new Date(itemEnd) > new Date(newEnd)) {
            newEnd = itemEnd;
          }
        });

        me.subgroups[subgroup].start = newStart;
        me.subgroups[subgroup].end = new Date(newEnd - 1); // -1 to compensate for colliding end to start subgroups;

      }
    }
  }

  /**
   * order subgroups
   */
  orderSubgroups() {
    if (this.subgroupOrderer !== undefined) {
      const sortArray = [];
      if (typeof this.subgroupOrderer == 'string') {
        for (const subgroup in this.subgroups) {
          sortArray.push({subgroup, sortField: this.subgroups[subgroup].items[0].data[this.subgroupOrderer]});
        }
        sortArray.sort((a, b) => a.sortField - b.sortField);
      }
      else if (typeof this.subgroupOrderer == 'function') {
        for (const subgroup in this.subgroups) {
          sortArray.push(this.subgroups[subgroup].items[0].data);
        }
        sortArray.sort(this.subgroupOrderer);
      }

      if (sortArray.length > 0) {
        for (let i = 0; i < sortArray.length; i++) {
          this.subgroups[sortArray[i].subgroup].index = i;
        }
      }
    }
  }

  /**
   * add item to subgroup
   */
  _resetSubgroups() {
    for (const subgroup in this.subgroups) {
      if (this.subgroups.hasOwnProperty(subgroup)) {
        this.subgroups[subgroup].visible = false;
        this.subgroups[subgroup].height = 0;
      }
    }
  }

  /**
   * Remove an item from the group
   * @param {Item} item
   */
  remove(item) {
    delete this.items[item.id];
    item.setParent(null);
    this.stackDirty = true;

    // remove from visible items
    const index = this.visibleItems.indexOf(item);
    if (index != -1) this.visibleItems.splice(index, 1);

    if(item.data.subgroup !== undefined){
      this._removeFromSubgroup(item);
      this.orderSubgroups();
    }
  }

  /**
   * remove item from subgroup
   * @param {object} item
   * @param {string} subgroupId
   */
  _removeFromSubgroup(item, subgroupId=item.data.subgroup) {
    if (subgroupId != undefined) {
      const subgroup = this.subgroups[subgroupId];
      if (subgroup){
        const itemIndex = subgroup.items.indexOf(item);
        //  Check the item is actually in this subgroup. How should items not in the group be handled?
        if (itemIndex >= 0) {
          subgroup.items.splice(itemIndex,1);
          if (!subgroup.items.length){
            delete this.subgroups[subgroupId];
          } else {
            this._updateSubgroupsSizes();
          }
        }
      }
    }
  }

  /**
   * Remove an item from the corresponding DataSet
   * @param {Item} item
   */
  removeFromDataSet(item) {
    this.itemSet.removeItem(item.id);
  }

  /**
   * Reorder the items
   */
  order() {
    const array = util$3.toArray(this.items);
    const startArray = [];
    const endArray = [];

    for (let i = 0; i < array.length; i++) {
      if (array[i].data.end !== undefined) {
        endArray.push(array[i]);
      }
      startArray.push(array[i]);
    }
    this.orderedItems = {
      byStart: startArray,
      byEnd: endArray
    };

    orderByStart(this.orderedItems.byStart);
    orderByEnd(this.orderedItems.byEnd);
  }

  /**
   * Update the visible items
   * @param {{byStart: Item[], byEnd: Item[]}} orderedItems   All items ordered by start date and by end date
   * @param {Item[]} oldVisibleItems                          The previously visible items.
   * @param {{start: number, end: number}} range              Visible range
   * @return {Item[]} visibleItems                            The new visible items.
   * @private
   */
  _updateItemsInRange(orderedItems, oldVisibleItems, range) {
    const visibleItems = [];
    const visibleItemsLookup = {}; // we keep this to quickly look up if an item already exists in the list without using indexOf on visibleItems

    if (!this.isVisible && this.groupId != ReservedGroupIds.BACKGROUND) {
      for (let i = 0; i < oldVisibleItems.length; i++) {
        var item = oldVisibleItems[i];
        if (item.displayed) item.hide();
      }
      return visibleItems;
    } 

    const interval = (range.end - range.start) / 4;
    const lowerBound = range.start - interval;
    const upperBound = range.end + interval;

    // this function is used to do the binary search for items having start date only.
    const startSearchFunction = value => {
      if      (value < lowerBound)  {return -1;}
      else if (value <= upperBound) {return  0;}
      else                          {return  1;}
    };

    // this function is used to do the binary search for items having start and end dates (range).
    const endSearchFunction = data => {
      const {start, end} = data;
      if      (end < lowerBound)    {return -1;}
      else if (start <= upperBound) {return  0;}
      else                          {return  1;}
    };

    // first check if the items that were in view previously are still in view.
    // IMPORTANT: this handles the case for the items with startdate before the window and enddate after the window!
    // also cleans up invisible items.
    if (oldVisibleItems.length > 0) {
      for (let i = 0; i < oldVisibleItems.length; i++) {
        this._checkIfVisibleWithReference(oldVisibleItems[i], visibleItems, visibleItemsLookup, range);
      }
    }

    // we do a binary search for the items that have only start values.
    const initialPosByStart = util$3.binarySearchCustom(orderedItems.byStart, startSearchFunction, 'data','start');

    // trace the visible items from the inital start pos both ways until an invisible item is found, we only look at the start values.
    this._traceVisible(initialPosByStart, orderedItems.byStart, visibleItems, visibleItemsLookup, item => item.data.start < lowerBound || item.data.start > upperBound);

    // if the window has changed programmatically without overlapping the old window, the ranged items with start < lowerBound and end > upperbound are not shown.
    // We therefore have to brute force check all items in the byEnd list
    if (this.checkRangedItems == true) {
      this.checkRangedItems = false;
      for (let i = 0; i < orderedItems.byEnd.length; i++) {
        this._checkIfVisibleWithReference(orderedItems.byEnd[i], visibleItems, visibleItemsLookup, range);
      }
    }
    else {
      // we do a binary search for the items that have defined end times.
      const initialPosByEnd = util$3.binarySearchCustom(orderedItems.byEnd, endSearchFunction, 'data');

      // trace the visible items from the inital start pos both ways until an invisible item is found, we only look at the end values.
      this._traceVisible(initialPosByEnd, orderedItems.byEnd, visibleItems, visibleItemsLookup, item => item.data.end < lowerBound || item.data.start > upperBound);
    }

    const redrawQueue = {};
    let redrawQueueLength = 0;

    for (let i = 0; i < visibleItems.length; i++) {
      const item = visibleItems[i];
      if (!item.displayed) {
        const returnQueue = true;
        redrawQueue[i] = item.redraw(returnQueue);
        redrawQueueLength = redrawQueue[i].length;
      }
    }

    const needRedraw = redrawQueueLength > 0;
    if (needRedraw) {
      // redraw all regular items
      for (let j = 0; j < redrawQueueLength; j++) {
        util$3.forEach(redrawQueue, fns => {
          fns[j]();
        });
      }
    }

    for (let i = 0; i < visibleItems.length; i++) {
      visibleItems[i].repositionX();
    }

    return visibleItems;
  }

  /**
   * trace visible items in group
   * @param {number} initialPos
   * @param {array} items
   * @param {aray} visibleItems
   * @param {object} visibleItemsLookup
   * @param {function} breakCondition
   */
  _traceVisible(initialPos, items, visibleItems, visibleItemsLookup, breakCondition) {
    if (initialPos != -1) {
      for (let i = initialPos; i >= 0; i--) {
        let item = items[i];
        if (breakCondition(item)) {
          break;
        }
        else {
          if (!(item.isCluster  && !item.hasItems()) && !item.cluster) {
            if (visibleItemsLookup[item.id] === undefined) {
              visibleItemsLookup[item.id] = true;
              visibleItems.push(item);
            }
          }
        }
      }

      for (let i = initialPos + 1; i < items.length; i++) {
        let item = items[i];
        if (breakCondition(item)) {
          break;
        }
        else {
          if (!(item.isCluster && !item.hasItems()) && !item.cluster) {
            if (visibleItemsLookup[item.id] === undefined) {
              visibleItemsLookup[item.id] = true;
              visibleItems.push(item);
            }
          }
        }
      }
    }
  }

  /**
   * this function is very similar to the _checkIfInvisible() but it does not
   * return booleans, hides the item if it should not be seen and always adds to
   * the visibleItems.
   * this one is for brute forcing and hiding.
   *
   * @param {Item} item
   * @param {Array} visibleItems
   * @param {{start:number, end:number}} range
   * @private
   */
  _checkIfVisible(item, visibleItems, range) {
      if (item.isVisible(range)) {
        if (!item.displayed) item.show();
        // reposition item horizontally
        item.repositionX();
        visibleItems.push(item);
      }
      else {
        if (item.displayed) item.hide();
      }
  }

  /**
   * this function is very similar to the _checkIfInvisible() but it does not
   * return booleans, hides the item if it should not be seen and always adds to
   * the visibleItems.
   * this one is for brute forcing and hiding.
   *
   * @param {Item} item
   * @param {Array.<timeline.Item>} visibleItems
   * @param {Object<number, boolean>} visibleItemsLookup
   * @param {{start:number, end:number}} range
   * @private
   */
  _checkIfVisibleWithReference(item, visibleItems, visibleItemsLookup, range) {
    if (item.isVisible(range)) {
      if (visibleItemsLookup[item.id] === undefined) {
        visibleItemsLookup[item.id] = true;
        visibleItems.push(item);
      }
    }
    else {
      if (item.displayed) item.hide();
    }
  }

  /**
   * Update the visible items
   * @param {array} orderedClusters 
   * @param {array} oldVisibleClusters                         
   * @param {{start: number, end: number}} range             
   * @return {Item[]} visibleItems                            
   * @private
   */
  _updateClustersInRange(orderedClusters, oldVisibleClusters, range) {
    // Clusters can overlap each other so we cannot use binary search here
    const visibleClusters = [];
    const visibleClustersLookup = {}; // we keep this to quickly look up if an item already exists in the list without using indexOf on visibleItems
  
    if (oldVisibleClusters.length > 0) {
      for (let i = 0; i < oldVisibleClusters.length; i++) {
        this._checkIfVisibleWithReference(oldVisibleClusters[i], visibleClusters, visibleClustersLookup, range);
      }
    }
  
    for (let i = 0; i < orderedClusters.byStart.length; i++) {
      this._checkIfVisibleWithReference(orderedClusters.byStart[i], visibleClusters, visibleClustersLookup, range);
    }
  
    for (let i = 0; i < orderedClusters.byEnd.length; i++) {
      this._checkIfVisibleWithReference(orderedClusters.byEnd[i], visibleClusters, visibleClustersLookup, range);
    }
  
    const redrawQueue = {};
    let redrawQueueLength = 0;
  
    for (let i = 0; i < visibleClusters.length; i++) {
      const item = visibleClusters[i];
      if (!item.displayed) {
        const returnQueue = true;
        redrawQueue[i] = item.redraw(returnQueue);
        redrawQueueLength = redrawQueue[i].length;
      }
    }
  
    const needRedraw = redrawQueueLength > 0;
    if (needRedraw) {
      // redraw all regular items
      for (var j = 0; j < redrawQueueLength; j++) {
        util$3.forEach(redrawQueue, function (fns) {
          fns[j]();
        });
      }
    }
  
    for (let i = 0; i < visibleClusters.length; i++) {
      visibleClusters[i].repositionX();
    }
    
    return visibleClusters;
  }

  /**
   * change item subgroup
   * @param {object} item
   * @param {string} oldSubgroup
   * @param {string} newSubgroup
   */
  changeSubgroup(item, oldSubgroup, newSubgroup) {
    this._removeFromSubgroup(item, oldSubgroup);
    this._addToSubgroup(item, newSubgroup);
    this.orderSubgroups();
  }

  /**
   * Call this method before you lose the last reference to an instance of this.
   * It will remove listeners etc.
   */
  dispose() {
    this.hide();

    let disposeCallback;
    while ((disposeCallback = this._disposeCallbacks.pop())) {
      disposeCallback();
    }
  }
}

/**
 * @constructor BackgroundGroup
 * @extends Group
 */
class BackgroundGroup extends Group {
  /**
 * @param {number | string} groupId
 * @param {Object} data
 * @param {ItemSet} itemSet
 */
  constructor(groupId, data, itemSet) {
    super(groupId, data, itemSet);
    // Group.call(this, groupId, data, itemSet);

    this.width = 0;
    this.height = 0;
    this.top = 0;
    this.left = 0;
  }

  /**
   * Repaint this group
   * @param {{start: number, end: number}} range
   * @param {{item: {horizontal: number, vertical: number}, axis: number}} margin
   * @param {boolean} [forceRestack=false]  Force restacking of all items
   * @return {boolean} Returns true if the group is resized
   */
  redraw(range, margin, forceRestack) {  // eslint-disable-line no-unused-vars
    const resized = false;

    this.visibleItems = this._updateItemsInRange(this.orderedItems, this.visibleItems, range);

    // calculate actual size
    this.width = this.dom.background.offsetWidth;

    // apply new height (just always zero for BackgroundGroup
    this.dom.background.style.height  = '0';

    // update vertical position of items after they are re-stacked and the height of the group is calculated
    for (let i = 0, ii = this.visibleItems.length; i < ii; i++) {
      const item = this.visibleItems[i];
      item.repositionY(margin);
    }

    return resized;
  }

  /**
   * Show this group: attach to the DOM
   */
  show() {
    if (!this.dom.background.parentNode) {
      this.itemSet.dom.background.appendChild(this.dom.background);
    }
  }
}

/**
 * Item
 */
class Item {
  /**
 * @constructor Item
 * @param {Object} data             Object containing (optional) parameters type,
 *                                  start, end, content, group, className.
 * @param {{toScreen: function, toTime: function}} conversion
 *                                  Conversion functions from time to screen and vice versa
 * @param {Object} options          Configuration options
 *                                  // TODO: describe available options
 */
  constructor(data, conversion, options) {
    this.id = null;
    this.parent = null;
    this.data = data;
    this.dom = null;
    this.conversion = conversion || {};
    this.defaultOptions = {
      locales,
      locale: 'en'
    };
    this.options = util$3.extend({}, this.defaultOptions, options);
    this.options.locales = util$3.extend({}, locales, this.options.locales);
    const defaultLocales = this.defaultOptions.locales[this.defaultOptions.locale];
    Object.keys(this.options.locales).forEach(locale => {
      this.options.locales[locale] = util$3.extend(
        {},
        defaultLocales,
        this.options.locales[locale]
      );
    });
    this.selected = false;
    this.displayed = false;
    this.groupShowing = true;
    this.selectable = (options && options.selectable) || false;
    this.dirty = true;

    this.top = null;
    this.right = null;
    this.left = null;
    this.width = null;
    this.height = null;

    this.setSelectability(data);

    this.editable = null;
    this._updateEditStatus();
  }

  /**
   * Select current item
   */
  select() {
    if (this.selectable) {
      this.selected = true;
      this.dirty = true;
      if (this.displayed) this.redraw();
    }
  }

  /**
   * Unselect current item
   */
  unselect() {
    this.selected = false;
    this.dirty = true;
    if (this.displayed) this.redraw();
  }

  /**
   * Set data for the item. Existing data will be updated. The id should not
   * be changed. When the item is displayed, it will be redrawn immediately.
   * @param {Object} data
   */
  setData(data) {
    const groupChanged = data.group != undefined && this.data.group != data.group;
    if (groupChanged && this.parent != null) {
      this.parent.itemSet._moveToGroup(this, data.group);
    }

    this.setSelectability(data);

    if (this.parent) {
      this.parent.stackDirty = true;
    }
    
    const subGroupChanged = data.subgroup != undefined && this.data.subgroup != data.subgroup;
    if (subGroupChanged && this.parent != null) {
      this.parent.changeSubgroup(this, this.data.subgroup, data.subgroup);
    }

    this.data = data;
    this._updateEditStatus();
    this.dirty = true;
    if (this.displayed) this.redraw();
  }

  /**
   * Set whether the item can be selected.
   * Can only be set/unset if the timeline's `selectable` configuration option is `true`.
   * @param {Object} data `data` from `constructor` and `setData`
   */
  setSelectability(data) {
    if (data) {
      this.selectable = typeof data.selectable === 'undefined' ? true : Boolean(data.selectable);
    }
  }

  /**
   * Set a parent for the item
   * @param {Group} parent
   */
  setParent(parent) {
    if (this.displayed) {
      this.hide();
      this.parent = parent;
      if (this.parent) {
        this.show();
      }
    }
    else {
      this.parent = parent;
    }
  }

  /**
   * Check whether this item is visible inside given range
   * @param {timeline.Range} range with a timestamp for start and end
   * @returns {boolean} True if visible
   */
  isVisible(range) {  // eslint-disable-line no-unused-vars
    return false;
  }

  /**
   * Show the Item in the DOM (when not already visible)
   * @return {Boolean} changed
   */
  show() {
    return false;
  }

  /**
   * Hide the Item from the DOM (when visible)
   * @return {Boolean} changed
   */
  hide() {
    return false;
  }

  /**
   * Repaint the item
   */
  redraw() {
    // should be implemented by the item
  }

  /**
   * Reposition the Item horizontally
   */
  repositionX() {
    // should be implemented by the item
  }

  /**
   * Reposition the Item vertically
   */
  repositionY() {
    // should be implemented by the item
  }

  /**
   * Repaint a drag area on the center of the item when the item is selected
   * @protected
   */
  _repaintDragCenter() {
    if (this.selected && this.editable.updateTime && !this.dom.dragCenter) {
      const me = this;
      // create and show drag area
      const dragCenter = document.createElement('div');
      dragCenter.className = 'vis-drag-center';
      dragCenter.dragCenterItem = this;
      this.hammerDragCenter = new Hammer$2(dragCenter);

      this.hammerDragCenter.on('tap', event => {
        me.parent.itemSet.body.emitter.emit('click',  {
          event,
          item: me.id
        });
      });
      this.hammerDragCenter.on('doubletap', event => {
        event.stopPropagation();
        me.parent.itemSet._onUpdateItem(me);
        me.parent.itemSet.body.emitter.emit('doubleClick', {
          event,
          item: me.id
        });
      });
      this.hammerDragCenter.on('panstart', event => {
        // do not allow this event to propagate to the Range
        event.stopPropagation();
        me.parent.itemSet._onDragStart(event);
      });
      this.hammerDragCenter.on('panmove',  me.parent.itemSet._onDrag.bind(me.parent.itemSet));
      this.hammerDragCenter.on('panend',   me.parent.itemSet._onDragEnd.bind(me.parent.itemSet));

      if (this.dom.box) {
        if (this.dom.dragLeft) {
          this.dom.box.insertBefore(dragCenter, this.dom.dragLeft);
        }
        else {
          this.dom.box.appendChild(dragCenter);
        }
      }
      else if (this.dom.point) {
        this.dom.point.appendChild(dragCenter);
      }
      
      this.dom.dragCenter = dragCenter;
    }
    else if (!this.selected && this.dom.dragCenter) {
      // delete drag area
      if (this.dom.dragCenter.parentNode) {
        this.dom.dragCenter.parentNode.removeChild(this.dom.dragCenter);
      }
      this.dom.dragCenter = null;
      
      if (this.hammerDragCenter) {
        this.hammerDragCenter.destroy();
        this.hammerDragCenter = null;
      }
    }
  }

  /**
   * Repaint a delete button on the top right of the item when the item is selected
   * @param {HTMLElement} anchor
   * @protected
   */
  _repaintDeleteButton(anchor) {
    const editable = ((this.options.editable.overrideItems || this.editable == null) && this.options.editable.remove) ||
                   (!this.options.editable.overrideItems && this.editable != null && this.editable.remove);

    if (this.selected && editable && !this.dom.deleteButton) {
      // create and show button
      const me = this;

      const deleteButton = document.createElement('div');

      if (this.options.rtl) {
        deleteButton.className = 'vis-delete-rtl';
      } else {
        deleteButton.className = 'vis-delete';
      }
      let optionsLocale = this.options.locales[this.options.locale];
      if (!optionsLocale) {
        if (!this.warned) {
          console.warn(`WARNING: options.locales['${this.options.locale}'] not found. See https://visjs.github.io/vis-timeline/docs/timeline/#Localization`);
          this.warned = true;
        }
        optionsLocale = this.options.locales['en']; // fall back on english when not available
      }
      deleteButton.title = optionsLocale.deleteSelected;

      // TODO: be able to destroy the delete button
      this.hammerDeleteButton = new Hammer$2(deleteButton).on('tap', event => {
        event.stopPropagation();
        me.parent.removeFromDataSet(me);
      });

      anchor.appendChild(deleteButton);
      this.dom.deleteButton = deleteButton;
    }
    else if (!this.selected && this.dom.deleteButton) {
      // remove button
      if (this.dom.deleteButton.parentNode) {
        this.dom.deleteButton.parentNode.removeChild(this.dom.deleteButton);
      }
      this.dom.deleteButton = null;

      if (this.hammerDeleteButton) {
        this.hammerDeleteButton.destroy();
        this.hammerDeleteButton = null;
      }
    }
  }

  /**
   * Repaint a onChange tooltip on the top right of the item when the item is selected
   * @param {HTMLElement} anchor
   * @protected
   */
  _repaintOnItemUpdateTimeTooltip(anchor) {
    if (!this.options.tooltipOnItemUpdateTime) return;

    const editable = (this.options.editable.updateTime || 
                    this.data.editable === true) &&
                   this.data.editable !== false;

    if (this.selected && editable && !this.dom.onItemUpdateTimeTooltip) {
      const onItemUpdateTimeTooltip = document.createElement('div');

      onItemUpdateTimeTooltip.className = 'vis-onUpdateTime-tooltip';
      anchor.appendChild(onItemUpdateTimeTooltip);
      this.dom.onItemUpdateTimeTooltip = onItemUpdateTimeTooltip;

    } else if (!this.selected && this.dom.onItemUpdateTimeTooltip) {
      // remove button
      if (this.dom.onItemUpdateTimeTooltip.parentNode) {
        this.dom.onItemUpdateTimeTooltip.parentNode.removeChild(this.dom.onItemUpdateTimeTooltip);
      }
      this.dom.onItemUpdateTimeTooltip = null;
    }

    // position onChange tooltip
    if (this.dom.onItemUpdateTimeTooltip) {

      // only show when editing
      this.dom.onItemUpdateTimeTooltip.style.visibility = this.parent.itemSet.touchParams.itemIsDragging ? 'visible' : 'hidden';
      
      // position relative to item's content
      this.dom.onItemUpdateTimeTooltip.style.transform = 'translateX(-50%)';
      this.dom.onItemUpdateTimeTooltip.style.left = '50%';

      // position above or below the item depending on the item's position in the window
      const tooltipOffset = 50; // TODO: should be tooltip height (depends on template)
      const scrollTop = this.parent.itemSet.body.domProps.scrollTop;

        // TODO: this.top for orientation:true is actually the items distance from the bottom... 
        // (should be this.bottom)
      let itemDistanceFromTop; 
      if (this.options.orientation.item == 'top') {
        itemDistanceFromTop = this.top;
      } else {
        itemDistanceFromTop = (this.parent.height - this.top - this.height);
      }
      const isCloseToTop = itemDistanceFromTop + this.parent.top - tooltipOffset < -scrollTop;

      if (isCloseToTop) {
        this.dom.onItemUpdateTimeTooltip.style.bottom = "";
        this.dom.onItemUpdateTimeTooltip.style.top = `${this.height + 2}px`;
      } else {
        this.dom.onItemUpdateTimeTooltip.style.top = "";
        this.dom.onItemUpdateTimeTooltip.style.bottom = `${this.height + 2}px`;
      }
      
      // handle tooltip content
      let content;
      let templateFunction;

      if (this.options.tooltipOnItemUpdateTime && this.options.tooltipOnItemUpdateTime.template) {
        templateFunction = this.options.tooltipOnItemUpdateTime.template.bind(this);
        content = templateFunction(this.data);
      } else {
        content = `start: ${moment$1(this.data.start).format('MM/DD/YYYY hh:mm')}`;
        if (this.data.end) { 
          content += `<br> end: ${moment$1(this.data.end).format('MM/DD/YYYY hh:mm')}`;
        }
      }
      this.dom.onItemUpdateTimeTooltip.innerHTML = util$3.xss(content);
    }
  }

   /**
   * get item data
   * @return {object}
   * @private
   */
  _getItemData() {
    return this.parent.itemSet.itemsData.get(this.id);
  }

  /**
   * Set HTML contents for the item
   * @param {Element} element   HTML element to fill with the contents
   * @private
   */
  _updateContents(element) {
    let content;
    let changed;
    let templateFunction;
    let itemVisibleFrameContent;
    let visibleFrameTemplateFunction; 
    const itemData = this._getItemData(); // get a clone of the data from the dataset

    const frameElement = this.dom.box || this.dom.point;
    const itemVisibleFrameContentElement = frameElement.getElementsByClassName('vis-item-visible-frame')[0];

    if (this.options.visibleFrameTemplate) {
      visibleFrameTemplateFunction = this.options.visibleFrameTemplate.bind(this);
      itemVisibleFrameContent = util$3.xss(visibleFrameTemplateFunction(itemData, itemVisibleFrameContentElement));
    } else {
      itemVisibleFrameContent = '';
    }
    
    if (itemVisibleFrameContentElement) {
      if ((itemVisibleFrameContent instanceof Object) && !(itemVisibleFrameContent instanceof Element)) {
        visibleFrameTemplateFunction(itemData, itemVisibleFrameContentElement);
      } else {
         changed = this._contentToString(this.itemVisibleFrameContent) !== this._contentToString(itemVisibleFrameContent);
         if (changed) {
          // only replace the content when changed
          if (itemVisibleFrameContent instanceof Element) {
            itemVisibleFrameContentElement.innerHTML = '';
            itemVisibleFrameContentElement.appendChild(itemVisibleFrameContent);
          }
          else if (itemVisibleFrameContent != undefined) {
            itemVisibleFrameContentElement.innerHTML = util$3.xss(itemVisibleFrameContent);
          }
          else {
            if (!(this.data.type == 'background' && this.data.content === undefined)) {
              throw new Error(`Property "content" missing in item ${this.id}`);
            }
          }

          this.itemVisibleFrameContent = itemVisibleFrameContent;
         }
      }
    }

    if (this.options.template) {
      templateFunction = this.options.template.bind(this);
      content = templateFunction(itemData, element, this.data);
    } else {
      content = this.data.content;
    }

    if ((content instanceof Object) && !(content instanceof Element)) {
      templateFunction(itemData, element);
    } else {
      changed = this._contentToString(this.content) !== this._contentToString(content);
      if (changed) {
        // only replace the content when changed
        if (content instanceof Element) {
          element.innerHTML = '';
          element.appendChild(content);
        }
        else if (content != undefined) {
          element.innerHTML = util$3.xss(content);
        }
        else {
          if (!(this.data.type == 'background' && this.data.content === undefined)) {
            throw new Error(`Property "content" missing in item ${this.id}`);
          }
        }
        this.content = content;
      }
    }
  }

  /**
   * Process dataAttributes timeline option and set as data- attributes on dom.content
   * @param {Element} element   HTML element to which the attributes will be attached
   * @private
   */
  _updateDataAttributes(element) {
   if (this.options.dataAttributes && this.options.dataAttributes.length > 0) {
     let attributes = [];

     if (Array.isArray(this.options.dataAttributes)) {
       attributes = this.options.dataAttributes;
     }
     else if (this.options.dataAttributes == 'all') {
       attributes = Object.keys(this.data);
     }
     else {
       return;
     }

     for (const name of attributes) {
       const value = this.data[name];

       if (value != null) {
         element.setAttribute(`data-${name}`, value);
       }
       else {
         element.removeAttribute(`data-${name}`);
       }
     }
   }
 }

  /**
   * Update custom styles of the element
   * @param {Element} element
   * @private
   */
  _updateStyle(element) {
    // remove old styles
    if (this.style) {
      util$3.removeCssText(element, this.style);
      this.style = null;
    }

    // append new styles
    if (this.data.style) {
      util$3.addCssText(element, this.data.style);
      this.style = this.data.style;
    }
  }

  /**
   * Stringify the items contents
   * @param {string | Element | undefined} content
   * @returns {string | undefined}
   * @private
   */
  _contentToString(content) {
    if (typeof content === 'string') return content;
    if (content && 'outerHTML' in content) return content.outerHTML;
    return content;
  }

  /**
   * Update the editability of this item.
   */
  _updateEditStatus() {
    if (this.options) {
      if(typeof this.options.editable === 'boolean') {
        this.editable = {
          updateTime: this.options.editable,
          updateGroup: this.options.editable,
          remove: this.options.editable
        };
      } else if(typeof this.options.editable === 'object') {
          this.editable = {};
          util$3.selectiveExtend(['updateTime', 'updateGroup', 'remove'], this.editable, this.options.editable);
      }
    }
    // Item data overrides, except if options.editable.overrideItems is set.
    if (!this.options || !(this.options.editable) || (this.options.editable.overrideItems !== true)) {
      if (this.data) {
        if (typeof this.data.editable === 'boolean') {
          this.editable = {
            updateTime: this.data.editable,
            updateGroup: this.data.editable,
            remove: this.data.editable
          };
        } else if (typeof this.data.editable === 'object') {
          // TODO: in timeline.js 5.0, we should change this to not reset options from the timeline configuration.
          // Basically just remove the next line...
          this.editable = {};
          util$3.selectiveExtend(['updateTime', 'updateGroup', 'remove'], this.editable, this.data.editable);
        }
      }
    }
  }

  /**
   * Return the width of the item left from its start date
   * @return {number}
   */
  getWidthLeft() {
    return 0;
  }

  /**
   * Return the width of the item right from the max of its start and end date
   * @return {number}
   */
  getWidthRight() {
    return 0;
  }

  /**
   * Return the title of the item
   * @return {string | undefined}
   */
  getTitle() {
    if (this.options.tooltip && this.options.tooltip.template) {
      const templateFunction = this.options.tooltip.template.bind(this);
      return templateFunction(this._getItemData(), this.data);
    }

    return this.data.title;
  }
}

Item.prototype.stack = true;

/**
 * @constructor BoxItem
 * @extends Item
 */
class BoxItem extends Item {
  /**
 * @param {Object} data             Object containing parameters start
 *                                  content, className.
 * @param {{toScreen: function, toTime: function}} conversion
 *                                  Conversion functions from time to screen and vice versa
 * @param {Object} [options]        Configuration options
 *                                  // TODO: describe available options
 */
  constructor(data, conversion, options) {
    super(data, conversion, options);
    this.props = {
      dot: {
        width: 0,
        height: 0
      },
      line: {
        width: 0,
        height: 0
      }
    };
    // validate data
    if (data) {
      if (data.start == undefined) {
        throw new Error(`Property "start" missing in item ${data}`);
      }
    }
  }

  /**
   * Check whether this item is visible inside given range
   * @param {{start: number, end: number}} range with a timestamp for start and end
   * @returns {boolean} True if visible
   */
  isVisible(range) {
    if (this.cluster) {
      return false;
    }
    // determine visibility
    let isVisible;
    const align = this.data.align || this.options.align;
    const widthInMs = this.width * range.getMillisecondsPerPixel();

    if (align == 'right') {
      isVisible = (this.data.start.getTime() > range.start) && (this.data.start.getTime() - widthInMs < range.end);
    }
    else if (align == 'left') {
      isVisible = (this.data.start.getTime() + widthInMs > range.start) && (this.data.start.getTime() < range.end);
    }
    else {
      // default or 'center'
      isVisible = (this.data.start.getTime() + widthInMs / 2 > range.start ) && (this.data.start.getTime() - widthInMs/2 < range.end);
    }
    return isVisible;
  }

   /**
   * create DOM element
   * @private
   */
  _createDomElement() {
    if (!this.dom) {
      // create DOM
      this.dom = {};

      // create main box
      this.dom.box = document.createElement('DIV');

      // contents box (inside the background box). used for making margins
      this.dom.content = document.createElement('DIV');
      this.dom.content.className = 'vis-item-content';
      this.dom.box.appendChild(this.dom.content);

      // line to axis
      this.dom.line = document.createElement('DIV');
      this.dom.line.className = 'vis-line';

      // dot on axis
      this.dom.dot = document.createElement('DIV');
      this.dom.dot.className = 'vis-dot';

      // attach this item as attribute
      this.dom.box['vis-item'] = this;

      this.dirty = true;
    }
  }

  /**
   * append DOM element
   * @private
   */
  _appendDomElement() {
    if (!this.parent) {
      throw new Error('Cannot redraw item: no parent attached');
    }
    if (!this.dom.box.parentNode) {
      const foreground = this.parent.dom.foreground;
      if (!foreground) throw new Error('Cannot redraw item: parent has no foreground container element');
      foreground.appendChild(this.dom.box);
    }
    if (!this.dom.line.parentNode) {
      var background = this.parent.dom.background;
      if (!background) throw new Error('Cannot redraw item: parent has no background container element');
      background.appendChild(this.dom.line);
    }
    if (!this.dom.dot.parentNode) {
      const axis = this.parent.dom.axis;
      if (!background) throw new Error('Cannot redraw item: parent has no axis container element');
      axis.appendChild(this.dom.dot);
    }
    this.displayed = true;
  }

  /**
   * update dirty DOM element
   * @private
   */
  _updateDirtyDomComponents() {
    // An item is marked dirty when:
    // - the item is not yet rendered
    // - the item's data is changed
    // - the item is selected/deselected
    if (this.dirty) {
      this._updateContents(this.dom.content);
      this._updateDataAttributes(this.dom.box);
      this._updateStyle(this.dom.box);

      const editable = (this.editable.updateTime || this.editable.updateGroup);

      // update class
      const className = (this.data.className ? ' ' + this.data.className : '') +
        (this.selected ? ' vis-selected' : '') +
        (editable ? ' vis-editable' : ' vis-readonly');
      this.dom.box.className = `vis-item vis-box${className}`;
      this.dom.line.className = `vis-item vis-line${className}`;
      this.dom.dot.className = `vis-item vis-dot${className}`;
    }
  }

  /**
   * get DOM components sizes
   * @return {object}
   * @private
   */
  _getDomComponentsSizes() {
    return {
      previous: {
        right: this.dom.box.style.right,
        left: this.dom.box.style.left
      },
      dot: {
        height: this.dom.dot.offsetHeight,
        width: this.dom.dot.offsetWidth
      },
      line: {
        width: this.dom.line.offsetWidth
      },
      box: {
        width: this.dom.box.offsetWidth,
        height: this.dom.box.offsetHeight
      }
    }
  }

  /**
   * update DOM components sizes
   * @param {object} sizes
   * @private
   */
  _updateDomComponentsSizes(sizes) {
    if (this.options.rtl) {
      this.dom.box.style.right = "0px";
    } else {
      this.dom.box.style.left = "0px";
    }

    // recalculate size
    this.props.dot.height = sizes.dot.height;
    this.props.dot.width = sizes.dot.width;
    this.props.line.width = sizes.line.width;
    this.width = sizes.box.width;
    this.height = sizes.box.height;

    // restore previous position
    if (this.options.rtl) {
      this.dom.box.style.right = sizes.previous.right;
    } else {
      this.dom.box.style.left = sizes.previous.left;
    }

    this.dirty = false;
  }

  /**
   * repaint DOM additionals
   * @private
   */
  _repaintDomAdditionals() {
    this._repaintOnItemUpdateTimeTooltip(this.dom.box);
    this._repaintDragCenter();
    this._repaintDeleteButton(this.dom.box);
  }

  /**
   * Repaint the item
   * @param {boolean} [returnQueue=false]  return the queue
   * @return {boolean} the redraw queue if returnQueue=true
   */
  redraw(returnQueue) {
    let sizes;
    const queue = [
      // create item DOM
      this._createDomElement.bind(this),

      // append DOM to parent DOM
      this._appendDomElement.bind(this),

      // update dirty DOM
      this._updateDirtyDomComponents.bind(this),

      () => {
        if (this.dirty) {
          sizes = this._getDomComponentsSizes();
        }
      },

      () => {
        if (this.dirty) {
          this._updateDomComponentsSizes.bind(this)(sizes);
        }
      },

      // repaint DOM additionals
      this._repaintDomAdditionals.bind(this)
    ];

    if (returnQueue) {
      return queue;
    } else {
      let result;
      queue.forEach(fn => {
        result = fn();
      });
      return result;
    }
  }

  /**
   * Show the item in the DOM (when not already visible). The items DOM will
   * be created when needed.
   * @param {boolean} [returnQueue=false]  whether to return a queue of functions to execute instead of just executing them
   * @return {boolean} the redraw queue if returnQueue=true
   */
  show(returnQueue) {
    if (!this.displayed) {
      return this.redraw(returnQueue);
    }
  }

  /**
   * Hide the item from the DOM (when visible)
   */
  hide() {
    if (this.displayed) {
      const dom = this.dom;

      if (dom.box.remove) dom.box.remove();
      else if (dom.box.parentNode) dom.box.parentNode.removeChild(dom.box); // IE11

      if (dom.line.remove) dom.line.remove();
      else if (dom.line.parentNode) dom.line.parentNode.removeChild(dom.line); // IE11
      
      if (dom.dot.remove) dom.dot.remove();
      else if (dom.dot.parentNode) dom.dot.parentNode.removeChild(dom.dot); // IE11

      this.displayed = false;
    }
  }

  /**
   * Reposition the item XY
   */
  repositionXY() {
    const rtl = this.options.rtl;

    const repositionXY = (element, x, y, rtl = false) => {
      if (x === undefined && y === undefined) return;
      // If rtl invert the number.
      const directionX = rtl ? (x * -1) : x;

      //no y. translate x
      if (y === undefined) {
        element.style.transform = `translateX(${directionX}px)`;
        return;
      }

      //no x. translate y
      if (x === undefined) {
        element.style.transform = `translateY(${y}px)`;
        return;
      }

      element.style.transform = `translate(${directionX}px, ${y}px)`;
    };
    repositionXY(this.dom.box, this.boxX, this.boxY, rtl);
    repositionXY(this.dom.dot, this.dotX, this.dotY, rtl);
    repositionXY(this.dom.line, this.lineX, this.lineY, rtl);
  }

  /**
   * Reposition the item horizontally
   * @Override
   */
  repositionX() {
    const start = this.conversion.toScreen(this.data.start);
    const align = this.data.align === undefined ? this.options.align : this.data.align;
    const lineWidth = this.props.line.width;
    const dotWidth = this.props.dot.width;
    
    if (align == 'right') {
      // calculate right position of the box
      this.boxX = start - this.width;
      this.lineX = start - lineWidth;
      this.dotX = start - lineWidth / 2 - dotWidth / 2;
    }
    else if (align == 'left') {
      // calculate left position of the box
      this.boxX = start;
      this.lineX = start;
      this.dotX = start + lineWidth / 2 - dotWidth / 2;
    }
    else {
      // default or 'center'
      this.boxX = start - this.width / 2;
      this.lineX = this.options.rtl ? start - lineWidth : start - lineWidth / 2;
      this.dotX = start - dotWidth / 2;
    }

    if (this.options.rtl)
      this.right = this.boxX;
    else
      this.left = this.boxX;

    this.repositionXY();
  }

  /**
   * Reposition the item vertically
   * @Override
   */
  repositionY() {
    const orientation = this.options.orientation.item;
    const lineStyle = this.dom.line.style;

    if (orientation == 'top') {
      const lineHeight = this.parent.top + this.top + 1;

      this.boxY = this.top || 0;
      lineStyle.height = `${lineHeight}px`;
      lineStyle.bottom = '';
      lineStyle.top = '0';
    }
    else { // orientation 'bottom'
      const itemSetHeight = this.parent.itemSet.props.height; // TODO: this is nasty
      const lineHeight = itemSetHeight - this.parent.top - this.parent.height + this.top;

      this.boxY = this.parent.height - this.top - (this.height || 0);
      lineStyle.height = `${lineHeight}px`;
      lineStyle.top = '';
      lineStyle.bottom = '0';
    }

    this.dotY = -this.props.dot.height / 2;

    this.repositionXY();
  }

  /**
   * Return the width of the item left from its start date
   * @return {number}
   */
  getWidthLeft() {
    return this.width / 2;
  }

  /**
   * Return the width of the item right from its start date
   * @return {number}
   */
  getWidthRight() {
    return this.width / 2;
  }
}

/**
 * @constructor PointItem
 * @extends Item
 */
class PointItem extends Item {
  /**
 * @param {Object} data             Object containing parameters start
 *                                  content, className.
 * @param {{toScreen: function, toTime: function}} conversion
 *                                  Conversion functions from time to screen and vice versa
 * @param {Object} [options]        Configuration options
 *                                  // TODO: describe available options
 */
  constructor(data, conversion, options) {
    super(data, conversion, options);
    this.props = {
      dot: {
        top: 0,
        width: 0,
        height: 0
      },
      content: {
        height: 0,
        marginLeft: 0,
        marginRight: 0
      }
    };
    // validate data
    if (data) {
      if (data.start == undefined) {
        throw new Error(`Property "start" missing in item ${data}`);
      }
    }
  }

  /**
   * Check whether this item is visible inside given range
   * @param {{start: number, end: number}} range with a timestamp for start and end
   * @returns {boolean} True if visible
   */
  isVisible(range) {
    if (this.cluster) {
      return false;
    }
    // determine visibility
    const widthInMs = this.width * range.getMillisecondsPerPixel();
    
    return (this.data.start.getTime() + widthInMs > range.start ) && (this.data.start < range.end);
  }

  /**
   * create DOM element
   * @private
   */
  _createDomElement() {
    if (!this.dom) {
      // create DOM
      this.dom = {};

      // background box
      this.dom.point = document.createElement('div');
      // className is updated in redraw()

      // contents box, right from the dot
      this.dom.content = document.createElement('div');
      this.dom.content.className = 'vis-item-content';
      this.dom.point.appendChild(this.dom.content);

      // dot at start
      this.dom.dot = document.createElement('div');
      this.dom.point.appendChild(this.dom.dot);

      // attach this item as attribute
      this.dom.point['vis-item'] = this;

      this.dirty = true;
    }
  }

  /**
   * append DOM element
   * @private
   */
  _appendDomElement() {
    if (!this.parent) {
      throw new Error('Cannot redraw item: no parent attached');
    }
    if (!this.dom.point.parentNode) {
      const foreground = this.parent.dom.foreground;
      if (!foreground) {
        throw new Error('Cannot redraw item: parent has no foreground container element');
      }
      foreground.appendChild(this.dom.point);
    }
    this.displayed = true;
  }

  /**
   * update dirty DOM components
   * @private
   */
  _updateDirtyDomComponents() {
    // An item is marked dirty when:
    // - the item is not yet rendered
    // - the item's data is changed
    // - the item is selected/deselected
    if (this.dirty) {
      this._updateContents(this.dom.content);
      this._updateDataAttributes(this.dom.point);
      this._updateStyle(this.dom.point);

      const editable = (this.editable.updateTime || this.editable.updateGroup);
      // update class
      const className = (this.data.className ? ' ' + this.data.className : '') +
          (this.selected ? ' vis-selected' : '') +
          (editable ? ' vis-editable' : ' vis-readonly');
      this.dom.point.className  = `vis-item vis-point${className}`;
      this.dom.dot.className  = `vis-item vis-dot${className}`;
    }
  }

  /**
   * get DOM component sizes
   * @return {object}
   * @private
   */
  _getDomComponentsSizes() {
    return {
      dot:  {
        width: this.dom.dot.offsetWidth,
        height: this.dom.dot.offsetHeight
      },
      content: {
        width: this.dom.content.offsetWidth,
        height: this.dom.content.offsetHeight
      },
      point: {
        width: this.dom.point.offsetWidth,
        height: this.dom.point.offsetHeight
      }
    }
  }

  /**
   * update DOM components sizes
   * @param {array} sizes
   * @private
   */
  _updateDomComponentsSizes(sizes) {
    // recalculate size of dot and contents
    this.props.dot.width = sizes.dot.width;
    this.props.dot.height = sizes.dot.height;
    this.props.content.height = sizes.content.height;

    // resize contents
    if (this.options.rtl) {
      this.dom.content.style.marginRight = `${2 * this.props.dot.width}px`;
    } else {
      this.dom.content.style.marginLeft = `${2 * this.props.dot.width}px`;
    }
    //this.dom.content.style.marginRight = ... + 'px'; // TODO: margin right

    // recalculate size
    this.width = sizes.point.width;
    this.height = sizes.point.height;

    // reposition the dot
    this.dom.dot.style.top = `${(this.height - this.props.dot.height) / 2}px`;
    
    const dotWidth = this.props.dot.width;
    const translateX = this.options.rtl ? (dotWidth / 2) * -1 : dotWidth / 2;
    this.dom.dot.style.transform = `translateX(${translateX}px`;
    this.dirty = false;
  }

  /**
   * Repain DOM additionals
   * @private
   */
  _repaintDomAdditionals() {
    this._repaintOnItemUpdateTimeTooltip(this.dom.point);
    this._repaintDragCenter();
    this._repaintDeleteButton(this.dom.point);
  }

  /**
   * Repaint the item
   * @param {boolean} [returnQueue=false]  return the queue
   * @return {boolean} the redraw queue if returnQueue=true
   */
  redraw(returnQueue) {
    let sizes;
    const queue = [
      // create item DOM
      this._createDomElement.bind(this),

      // append DOM to parent DOM
      this._appendDomElement.bind(this),

      // update dirty DOM
      this._updateDirtyDomComponents.bind(this),

      () => {
        if (this.dirty) {
          sizes = this._getDomComponentsSizes();
        }
      },

      () => {
        if (this.dirty) {
          this._updateDomComponentsSizes.bind(this)(sizes);
        }
      },

      // repaint DOM additionals
      this._repaintDomAdditionals.bind(this)
    ];

    if (returnQueue) {
      return queue;
    } else {
      let result;
      queue.forEach(fn => {
        result = fn();
      });
      return result;
    }
  }

  
  /**
   * Reposition XY
   */
  repositionXY() {
    const rtl = this.options.rtl;
    
    const repositionXY = (element, x, y, rtl = false) => {
      if (x === undefined && y === undefined) return;
      // If rtl invert the number.
      const directionX = rtl ? (x * -1) : x;

      //no y. translate x
      if (y === undefined) {
        element.style.transform = `translateX(${directionX}px)`;
        return;
      }

      //no x. translate y
      if (x === undefined) {
        element.style.transform = `translateY(${y}px)`;
        return;
      }

      element.style.transform = `translate(${directionX}px, ${y}px)`;
    };
    repositionXY(this.dom.point, this.pointX, this.pointY, rtl);
  }

  /**
   * Show the item in the DOM (when not already visible). The items DOM will
   * be created when needed.
   * @param {boolean} [returnQueue=false]  whether to return a queue of functions to execute instead of just executing them
   * @return {boolean} the redraw queue if returnQueue=true
   */
  show(returnQueue) {
    if (!this.displayed) {
      return this.redraw(returnQueue);
    }
  }

  /**
   * Hide the item from the DOM (when visible)
   */
  hide() {
    if (this.displayed) {
      if (this.dom.point.parentNode) {
        this.dom.point.parentNode.removeChild(this.dom.point);
      }

      this.displayed = false;
    }
  }

  /**
   * Reposition the item horizontally
   * @Override
   */
  repositionX() {
    const start = this.conversion.toScreen(this.data.start);

    this.pointX = start;
    if (this.options.rtl) {
      this.right = start - this.props.dot.width;
    } else {
      this.left = start - this.props.dot.width;
    }

    this.repositionXY();
  }

  /**
   * Reposition the item vertically
   * @Override
   */
  repositionY() {
    const orientation = this.options.orientation.item;
    if (orientation == 'top') {
      this.pointY = this.top;
    }
    else {
      this.pointY = this.parent.height - this.top - this.height;
    }

    this.repositionXY();
  }

  /**
   * Return the width of the item left from its start date
   * @return {number}
   */
  getWidthLeft() {
    return this.props.dot.width;
  }

  /**
   * Return the width of the item right from  its start date
   * @return {number}
   */
  getWidthRight() {
    return this.props.dot.width;
  }
}

/**
 * @constructor RangeItem
 * @extends Item
 */
class RangeItem extends Item {
  /**
 * @param {Object} data             Object containing parameters start, end
 *                                  content, className.
 * @param {{toScreen: function, toTime: function}} conversion
 *                                  Conversion functions from time to screen and vice versa
 * @param {Object} [options]        Configuration options
 *                                  // TODO: describe options
 */
  constructor(data, conversion, options) {
    super(data, conversion, options);
    this.props = {
      content: {
        width: 0
      }
    };
    this.overflow = false; // if contents can overflow (css styling), this flag is set to true
    // validate data
    if (data) {
      if (data.start == undefined) {
        throw new Error(`Property "start" missing in item ${data.id}`);
      }
      if (data.end == undefined) {
        throw new Error(`Property "end" missing in item ${data.id}`);
      }
    }
  }

  /**
   * Check whether this item is visible inside given range
   *
   * @param {timeline.Range} range with a timestamp for start and end
   * @returns {boolean} True if visible
   */
  isVisible(range) {
    if (this.cluster) {
      return false;
    }
    // determine visibility
    return (this.data.start < range.end) && (this.data.end > range.start);
  }

  /**
   * create DOM elements
   * @private
   */
  _createDomElement() {
    if (!this.dom) {
      // create DOM
      this.dom = {};

        // background box
      this.dom.box = document.createElement('div');
      // className is updated in redraw()

      // frame box (to prevent the item contents from overflowing)
      this.dom.frame = document.createElement('div');
      this.dom.frame.className = 'vis-item-overflow';
      this.dom.box.appendChild(this.dom.frame);
    
      // visible frame box (showing the frame that is always visible)
      this.dom.visibleFrame = document.createElement('div');
      this.dom.visibleFrame.className = 'vis-item-visible-frame';
      this.dom.box.appendChild(this.dom.visibleFrame);

      // contents box
      this.dom.content = document.createElement('div');
      this.dom.content.className = 'vis-item-content';
      this.dom.frame.appendChild(this.dom.content);

      // attach this item as attribute
      this.dom.box['vis-item'] = this;

      this.dirty = true;
    }

  }

  /**
   * append element to DOM
   * @private
   */
  _appendDomElement() {
    if (!this.parent) {
      throw new Error('Cannot redraw item: no parent attached');
    }
    if (!this.dom.box.parentNode) {
      const foreground = this.parent.dom.foreground;
      if (!foreground) {
        throw new Error('Cannot redraw item: parent has no foreground container element');
      }
      foreground.appendChild(this.dom.box);
    }
    this.displayed = true;
  }

  /**
   * update dirty DOM components
   * @private
   */
  _updateDirtyDomComponents() {
    // update dirty DOM. An item is marked dirty when:
    // - the item is not yet rendered
    // - the item's data is changed
    // - the item is selected/deselected
    if (this.dirty) {
      this._updateContents(this.dom.content);
      this._updateDataAttributes(this.dom.box);
      this._updateStyle(this.dom.box);

      const editable = (this.editable.updateTime || this.editable.updateGroup);

      // update class
      const className = (this.data.className ? (' ' + this.data.className) : '') +
          (this.selected ? ' vis-selected' : '') + 
          (editable ? ' vis-editable' : ' vis-readonly');
      this.dom.box.className = this.baseClassName + className;

      // turn off max-width to be able to calculate the real width
      // this causes an extra browser repaint/reflow, but so be it
      this.dom.content.style.maxWidth = 'none';
    }
  }

  /**
   * get DOM component sizes
   * @return {object}
   * @private
   */
  _getDomComponentsSizes() {
    // determine from css whether this box has overflow
    this.overflow = window.getComputedStyle(this.dom.frame).overflow !== 'hidden';
    this.whiteSpace = window.getComputedStyle(this.dom.content).whiteSpace !== 'nowrap';
    return {
      content: {
        width: this.dom.content.offsetWidth,
      },
      box: {
        height: this.dom.box.offsetHeight
      }
    }
  }

  /**
   * update DOM component sizes
   * @param {array} sizes
   * @private
   */
  _updateDomComponentsSizes(sizes) {
    this.props.content.width = sizes.content.width;
    this.height = sizes.box.height;
    this.dom.content.style.maxWidth = '';
    this.dirty = false;
  }

  /**
   * repaint DOM additional components
   * @private
   */
  _repaintDomAdditionals() {
    this._repaintOnItemUpdateTimeTooltip(this.dom.box);
    this._repaintDeleteButton(this.dom.box);
    this._repaintDragCenter();
    this._repaintDragLeft();
    this._repaintDragRight();
  }

  /**
   * Repaint the item
   * @param {boolean} [returnQueue=false]  return the queue
   * @return {boolean} the redraw queue if returnQueue=true
   */
  redraw(returnQueue) {
    let sizes;
    const queue = [
      // create item DOM
      this._createDomElement.bind(this),

      // append DOM to parent DOM
      this._appendDomElement.bind(this),

      // update dirty DOM 
      this._updateDirtyDomComponents.bind(this),

      () => {
        if (this.dirty) {
          sizes = this._getDomComponentsSizes.bind(this)();
        }
      },

      () => {
        if (this.dirty) {
          this._updateDomComponentsSizes.bind(this)(sizes);
        }
      },

      // repaint DOM additionals
      this._repaintDomAdditionals.bind(this)
    ];

    if (returnQueue) {
      return queue;
    } else {
      let result;
      queue.forEach(fn => {
        result = fn();
      });
      return result;
    }
  }

  /**
   * Show the item in the DOM (when not already visible). The items DOM will
   * be created when needed.
   * @param {boolean} [returnQueue=false]  whether to return a queue of functions to execute instead of just executing them
   * @return {boolean} the redraw queue if returnQueue=true
   */
  show(returnQueue) {
    if (!this.displayed) {
      return this.redraw(returnQueue);
    }
  }

  /**
   * Hide the item from the DOM (when visible)
   */
  hide() {
    if (this.displayed) {
      const box = this.dom.box;

      if (box.parentNode) {
        box.parentNode.removeChild(box);
      }

      this.displayed = false;
    }
  }

  /**
   * Reposition the item horizontally
   * @param {boolean} [limitSize=true] If true (default), the width of the range
   *                                   item will be limited, as the browser cannot
   *                                   display very wide divs. This means though
   *                                   that the applied left and width may
   *                                   not correspond to the ranges start and end
   * @Override
   */
  repositionX(limitSize) {
    const parentWidth = this.parent.width;
    let start = this.conversion.toScreen(this.data.start);
    let end = this.conversion.toScreen(this.data.end);
    const align = this.data.align === undefined ? this.options.align : this.data.align;
    let contentStartPosition;
    let contentWidth;

    // limit the width of the range, as browsers cannot draw very wide divs
    // unless limitSize: false is explicitly set in item data
    if (this.data.limitSize !== false && (limitSize === undefined || limitSize === true)) {
      if (start < -parentWidth) {
        start = -parentWidth;
      }
      if (end > 2 * parentWidth) {
        end = 2 * parentWidth;
      }
    }

    //round to 3 decimals to compensate floating-point values rounding
    const boxWidth = Math.max(Math.round((end - start) * 1000) / 1000, 1);

    if (this.overflow) {
      if (this.options.rtl) {
        this.right = start;
      } else {
        this.left = start;
      }
      this.width = boxWidth + this.props.content.width;
      contentWidth = this.props.content.width;

      // Note: The calculation of width is an optimistic calculation, giving
      //       a width which will not change when moving the Timeline
      //       So no re-stacking needed, which is nicer for the eye;
    }
    else {
      if (this.options.rtl) {
        this.right = start;
      } else {
        this.left = start;
      }
      this.width = boxWidth;
      contentWidth = Math.min(end - start, this.props.content.width);
    }

    if (this.options.rtl) {
      this.dom.box.style.transform = `translateX(${this.right * -1}px)`;
    } else {
      this.dom.box.style.transform = `translateX(${this.left}px)`;
    }
    this.dom.box.style.width = `${boxWidth}px`;
    if (this.whiteSpace) {
        this.height = this.dom.box.offsetHeight;
    }

    switch (align) {
      case 'left':
        this.dom.content.style.transform = 'translateX(0)';
        break;

      case 'right':
        if (this.options.rtl) {
          const translateX = Math.max((boxWidth - contentWidth), 0) * -1;
          this.dom.content.style.transform = `translateX(${translateX}px)`;
        } else {
          this.dom.content.style.transform = `translateX(${Math.max((boxWidth - contentWidth), 0)}px)`;
        }
        break;

      case 'center':
        if (this.options.rtl) {
          const translateX = Math.max((boxWidth - contentWidth) / 2, 0) * -1;
          this.dom.content.style.transform = `translateX(${translateX}px)`;
        } else {
          this.dom.content.style.transform = `translateX(${Math.max((boxWidth - contentWidth) / 2, 0)}px)`;
        }
        
        break;

      default: // 'auto'
        // when range exceeds left of the window, position the contents at the left of the visible area
        if (this.overflow) {
          if (end > 0) {
            contentStartPosition = Math.max(-start, 0);
          }
          else {
            contentStartPosition = -contentWidth; // ensure it's not visible anymore
          }
        }
        else {
          if (start < 0) {
            contentStartPosition = -start;
          }
          else {
            contentStartPosition = 0;
          }
        }
        if (this.options.rtl) {
          const translateX = contentStartPosition * -1;
          this.dom.content.style.transform = `translateX(${translateX}px)`;
        } else {
          this.dom.content.style.transform = `translateX(${contentStartPosition}px)`;
          // this.dom.content.style.width = `calc(100% - ${contentStartPosition}px)`;
        }
    }
  }

  /**
   * Reposition the item vertically
   * @Override
   */
  repositionY() {
    const orientation = this.options.orientation.item;
    const box = this.dom.box;

    if (orientation == 'top') {
      box.style.top = `${this.top}px`;
    }
    else {
      box.style.top = `${this.parent.height - this.top - this.height}px`;
    }
  }

  /**
   * Repaint a drag area on the left side of the range when the range is selected
   * @protected
   */
  _repaintDragLeft() {
    if ((this.selected || this.options.itemsAlwaysDraggable.range) && this.editable.updateTime && !this.dom.dragLeft) {
      // create and show drag area
      const dragLeft = document.createElement('div');
      dragLeft.className = 'vis-drag-left';
      dragLeft.dragLeftItem = this;

      this.dom.box.appendChild(dragLeft);
      this.dom.dragLeft = dragLeft;
    }
    else if (!this.selected && !this.options.itemsAlwaysDraggable.range && this.dom.dragLeft) {
      // delete drag area
      if (this.dom.dragLeft.parentNode) {
        this.dom.dragLeft.parentNode.removeChild(this.dom.dragLeft);
      }
      this.dom.dragLeft = null;
    }
  }

  /**
   * Repaint a drag area on the right side of the range when the range is selected
   * @protected
   */
  _repaintDragRight() {
    if ((this.selected || this.options.itemsAlwaysDraggable.range) && this.editable.updateTime && !this.dom.dragRight) {
      // create and show drag area
      const dragRight = document.createElement('div');
      dragRight.className = 'vis-drag-right';
      dragRight.dragRightItem = this;

      this.dom.box.appendChild(dragRight);
      this.dom.dragRight = dragRight;
    }
    else if (!this.selected && !this.options.itemsAlwaysDraggable.range && this.dom.dragRight) {
      // delete drag area
      if (this.dom.dragRight.parentNode) {
        this.dom.dragRight.parentNode.removeChild(this.dom.dragRight);
      }
      this.dom.dragRight = null;
    }
  }
}

RangeItem.prototype.baseClassName = 'vis-item vis-range';

/**
 * @constructor BackgroundItem
 * @extends Item
 */
class BackgroundItem extends Item {
  /**
 * @constructor BackgroundItem
 * @param {Object} data             Object containing parameters start, end
 *                                  content, className.
 * @param {{toScreen: function, toTime: function}} conversion
 *                                  Conversion functions from time to screen and vice versa
 * @param {Object} [options]        Configuration options
 *                                  // TODO: describe options
 * // TODO: implement support for the BackgroundItem just having a start, then being displayed as a sort of an annotation
 */
  constructor(data, conversion, options) {
    super(data, conversion, options);
    this.props = {
      content: {
        width: 0
      }
    };
    this.overflow = false; // if contents can overflow (css styling), this flag is set to true

    // validate data
    if (data) {
      if (data.start == undefined) {
        throw new Error(`Property "start" missing in item ${data.id}`);
      }
      if (data.end == undefined) {
        throw new Error(`Property "end" missing in item ${data.id}`);
      }
    }
  }

  /**
   * Check whether this item is visible inside given range
   * @param {timeline.Range} range with a timestamp for start and end
   * @returns {boolean} True if visible
   */
  isVisible(range) {
    // determine visibility
    return (this.data.start < range.end) && (this.data.end > range.start); 
  }

  /**
   * create DOM element
   * @private
   */
  _createDomElement() {
    if (!this.dom) {
      // create DOM
      this.dom = {};

      // background box
      this.dom.box = document.createElement('div');
      // className is updated in redraw()

      // frame box (to prevent the item contents from overflowing
      this.dom.frame = document.createElement('div');
      this.dom.frame.className = 'vis-item-overflow';
      this.dom.box.appendChild(this.dom.frame);

      // contents box
      this.dom.content = document.createElement('div');
      this.dom.content.className = 'vis-item-content';
      this.dom.frame.appendChild(this.dom.content);

      // Note: we do NOT attach this item as attribute to the DOM,
      //       such that background items cannot be selected
      //this.dom.box['vis-item'] = this;

      this.dirty = true;
    }
  }

  /**
   * append DOM element
   * @private
   */
  _appendDomElement() {
    if (!this.parent) {
      throw new Error('Cannot redraw item: no parent attached');
    }
    if (!this.dom.box.parentNode) {
      const background = this.parent.dom.background;
      if (!background) {
        throw new Error('Cannot redraw item: parent has no background container element');
      }
      background.appendChild(this.dom.box);
    }
    this.displayed = true;
  }

  /**
   * update DOM Dirty components
   * @private
   */
  _updateDirtyDomComponents() {
    // update dirty DOM. An item is marked dirty when:
    // - the item is not yet rendered
    // - the item's data is changed
    // - the item is selected/deselected
    if (this.dirty) {
      this._updateContents(this.dom.content);
      this._updateDataAttributes(this.dom.content);
      this._updateStyle(this.dom.box);

      // update class
      const className = (this.data.className ? (' ' + this.data.className) : '') +
          (this.selected ? ' vis-selected' : '');
      this.dom.box.className = this.baseClassName + className;
    }
  }

  /**
   * get DOM components sizes
   * @return {object}
   * @private
   */
  _getDomComponentsSizes() {
    // determine from css whether this box has overflow
    this.overflow = window.getComputedStyle(this.dom.content).overflow !== 'hidden';
    return {
      content: {
        width: this.dom.content.offsetWidth
      }
    }
  }

  /**
   * update DOM components sizes
   * @param {object} sizes
   * @private
   */
  _updateDomComponentsSizes(sizes) {
    // recalculate size
    this.props.content.width = sizes.content.width;
    this.height = 0; // set height zero, so this item will be ignored when stacking items

    this.dirty = false;
  }

  /**
   * repaint DOM additionals
   * @private
   */
  _repaintDomAdditionals() {
  }

  /**
   * Repaint the item
   * @param {boolean} [returnQueue=false]  return the queue
   * @return {boolean} the redraw result or the redraw queue if returnQueue=true
   */
  redraw(returnQueue) {
    let sizes;
    const queue = [
      // create item DOM
      this._createDomElement.bind(this),

      // append DOM to parent DOM
      this._appendDomElement.bind(this),

      this._updateDirtyDomComponents.bind(this),

      () => {
        if (this.dirty) {
          sizes = this._getDomComponentsSizes.bind(this)();
        }
      },

      () => {
        if (this.dirty) {
          this._updateDomComponentsSizes.bind(this)(sizes);
        }
      },

      // repaint DOM additionals
      this._repaintDomAdditionals.bind(this)
    ];

    if (returnQueue) {
      return queue;
    } else {
      let result;
      queue.forEach(fn => {
        result = fn();
      });
      return result;
    }
  }

  /**
   * Reposition the item vertically
   * @Override
   */
  repositionY(margin) {  // eslint-disable-line no-unused-vars
    let height;
    const orientation = this.options.orientation.item;

    // special positioning for subgroups
    if (this.data.subgroup !== undefined) {
      // TODO: instead of calculating the top position of the subgroups here for every BackgroundItem, calculate the top of the subgroup once in Itemset
      const itemSubgroup = this.data.subgroup;

      this.dom.box.style.height = `${this.parent.subgroups[itemSubgroup].height}px`;

      if (orientation == 'top') { 
        this.dom.box.style.top = `${this.parent.top + this.parent.subgroups[itemSubgroup].top}px`;
      } else {
        this.dom.box.style.top = `${this.parent.top + this.parent.height - this.parent.subgroups[itemSubgroup].top - this.parent.subgroups[itemSubgroup].height}px`;
      }
      this.dom.box.style.bottom = '';
    }
    // and in the case of no subgroups:
    else {
      // we want backgrounds with groups to only show in groups.
      if (this.parent instanceof BackgroundGroup) {
        // if the item is not in a group:
        height = Math.max(this.parent.height,
            this.parent.itemSet.body.domProps.center.height,
            this.parent.itemSet.body.domProps.centerContainer.height);
        this.dom.box.style.bottom = orientation == 'bottom' ? '0' : '';
        this.dom.box.style.top = orientation == 'top' ? '0' : '';
      }
      else {
        height = this.parent.height;
        // same alignment for items when orientation is top or bottom
        this.dom.box.style.top = `${this.parent.top}px`;
        this.dom.box.style.bottom = '';
      }
    }
    this.dom.box.style.height = `${height}px`;
  }
}

BackgroundItem.prototype.baseClassName = 'vis-item vis-background';

BackgroundItem.prototype.stack = false;

/**
 * Show the item in the DOM (when not already visible). The items DOM will
 * be created when needed.
 */
BackgroundItem.prototype.show = RangeItem.prototype.show;

/**
 * Hide the item from the DOM (when visible)
 * @return {Boolean} changed
 */
BackgroundItem.prototype.hide = RangeItem.prototype.hide;

/**
 * Reposition the item horizontally
 * @Override
 */
BackgroundItem.prototype.repositionX = RangeItem.prototype.repositionX;

/**
 * Popup is a class to create a popup window with some text
 */
class Popup$2 {
  /**
   * @param {Element} container       The container object.
   * @param {string}  overflowMethod  How the popup should act to overflowing ('flip', 'cap' or 'none')
   */
  constructor(container, overflowMethod) {
    this.container = container;
    this.overflowMethod = overflowMethod || 'cap';

    this.x = 0;
    this.y = 0;
    this.padding = 5;
    this.hidden = false;

    // create the frame
    this.frame = document.createElement('div');
    this.frame.className = 'vis-tooltip';
    this.container.appendChild(this.frame);
  }

  /**
   * @param {number} x   Horizontal position of the popup window
   * @param {number} y   Vertical position of the popup window
   */
  setPosition(x, y) {
    this.x = parseInt(x);
    this.y = parseInt(y);
  }

  /**
   * Set the content for the popup window. This can be HTML code or text.
   * @param {string | Element} content
   */
  setText(content) {
    if (content instanceof Element) {
      this.frame.innerHTML = '';
      this.frame.appendChild(content);
    }
    else {
      this.frame.innerHTML = util$3.xss(content); // string containing text or HTML
    }
  }

  /**
   * Show the popup window
   * @param {boolean} [doShow]    Show or hide the window
   */
  show(doShow) {
    if (doShow === undefined) {
      doShow = true;
    }

    if (doShow === true) {
      var height = this.frame.clientHeight;
      var width = this.frame.clientWidth;
      var maxHeight = this.frame.parentNode.clientHeight;
      var maxWidth = this.frame.parentNode.clientWidth;

      var left = 0, top = 0;

      if (this.overflowMethod == 'flip' || this.overflowMethod == 'none') {
        let isLeft = false, isTop = true; // Where around the position it's located

        if (this.overflowMethod == 'flip') {
          if (this.y - height < this.padding) {
            isTop = false;
          }

          if (this.x + width > maxWidth - this.padding) {
            isLeft = true;
          }
        }

        if (isLeft) {
          left = this.x - width;
        } else {
          left = this.x;
        }

        if (isTop) {
          top = this.y - height;
        } else {
          top = this.y;
        }
      } else { // this.overflowMethod == 'cap'
        top = (this.y - height);
        if (top + height + this.padding > maxHeight) {
          top = maxHeight - height - this.padding;
        }
        if (top < this.padding) {
          top = this.padding;
        }

        left = this.x;
        if (left + width + this.padding > maxWidth) {
          left = maxWidth - width - this.padding;
        }
        if (left < this.padding) {
          left = this.padding;
        }
      }

      this.frame.style.left = left + "px";
      this.frame.style.top = top + "px";
      this.frame.style.visibility = "visible";
      this.hidden = false;
    }
    else {
      this.hide();
    }
  }

  /**
   * Hide the popup window
   */
  hide() {
    this.hidden = true;
    this.frame.style.left = "0";
    this.frame.style.top = "0";
    this.frame.style.visibility = "hidden";
  }

  /**
   * Remove the popup window
   */
  destroy() {
    this.frame.parentNode.removeChild(this.frame); // Remove element from DOM
  }
}

/**
 * ClusterItem
 */
class ClusterItem extends Item {
  /**
 * @constructor Item
 * @param {Object} data             Object containing (optional) parameters type,
 *                                  start, end, content, group, className.
 * @param {{toScreen: function, toTime: function}} conversion
 *                                  Conversion functions from time to screen and vice versa
 * @param {Object} options          Configuration options
 *                                  // TODO: describe available options
 */
  constructor(data, conversion, options) {
    const modifiedOptions = Object.assign({}, {fitOnDoubleClick: true}, options, {editable: false});
    super(data, conversion, modifiedOptions);

    this.props = {
      content: {
        width: 0,
        height: 0
      },
    };
    
    if (!data || data.uiItems == undefined) {
      throw new Error('Property "uiItems" missing in item ' + data.id);
    }
  
    this.id = dist.v4();
    this.group = data.group;
    this._setupRange();
  
    this.emitter = this.data.eventEmitter;
    this.range = this.data.range;
    this.attached = false;
    this.isCluster = true;
    this.data.isCluster = true;
  }

  /**
   * check if there are items
   * @return {boolean}
   */
  hasItems() {
    return this.data.uiItems && this.data.uiItems.length && this.attached;
  }
  
  /**
   * set UI items
   * @param {array} items
   */
  setUiItems(items) {
    this.detach();
  
    this.data.uiItems = items;
  
    this._setupRange();
  
    this.attach();
  }
  
  /**
   * check is visible
   * @param {object} range
   * @return {boolean}
   */
  isVisible(range) {
    const rangeWidth = this.data.end ? this.data.end - this.data.start : 0;
    const widthInMs = this.width * range.getMillisecondsPerPixel();
    const end = Math.max(this.data.start.getTime() + rangeWidth, this.data.start.getTime() + widthInMs);
    return (this.data.start < range.end) && (end > range.start) && this.hasItems();
  }
  
  /**
   * get cluster data
   * @return {object}
   */
  getData() {
    return {
      isCluster: true,
      id: this.id,
      items: this.data.items || [],
      data: this.data
    }
  }
  
  /**
   * redraw cluster item
   * @param {boolean} returnQueue
   * @return {boolean}
   */
  redraw (returnQueue) {
    var sizes;
    var queue = [
      // create item DOM
      this._createDomElement.bind(this),
  
      // append DOM to parent DOM
      this._appendDomElement.bind(this),
  
      // update dirty DOM
      this._updateDirtyDomComponents.bind(this),
  
      (function () {
        if (this.dirty) {
          sizes = this._getDomComponentsSizes();
        }
      }).bind(this),
  
      (function () {
        if (this.dirty) {
          this._updateDomComponentsSizes.bind(this)(sizes);
        }
      }).bind(this),
  
      // repaint DOM additionals
      this._repaintDomAdditionals.bind(this)
    ];
  
    if (returnQueue) {
      return queue;
    } else {
      var result;
      queue.forEach(function (fn) {
        result = fn();
      });
      return result;
    }
  }
  
  /**
   * show cluster item
   */
  show() {
    if (!this.displayed) {
      this.redraw();
    }
  }
  
  /**
   * Hide the item from the DOM (when visible)
   */
  hide() {
    if (this.displayed) {
      var dom = this.dom;
      if (dom.box.parentNode) {
        dom.box.parentNode.removeChild(dom.box);
      }

      if (this.options.showStipes) {
        if (dom.line.parentNode)  {
          dom.line.parentNode.removeChild(dom.line);
        }
        if (dom.dot.parentNode)  {
          dom.dot.parentNode.removeChild(dom.dot);
        }
      }
      this.displayed = false;
    }
  }
  
  /**
   * reposition item x axis
   */
  repositionX() {
    let start = this.conversion.toScreen(this.data.start);
    let end = this.data.end ? this.conversion.toScreen(this.data.end) : 0;
    if (end) {
      this.repositionXWithRanges(start, end);
    } else {
      let align = this.data.align === undefined ? this.options.align : this.data.align;
      this.repositionXWithoutRanges(start, align);
    }
  
    if (this.options.showStipes) {
      this.dom.line.style.display = this._isStipeVisible() ? 'block' : 'none';
      this.dom.dot.style.display = this._isStipeVisible() ? 'block' : 'none';

      if (this._isStipeVisible()) {
        this.repositionStype(start, end);
      }
    }
  }

  /**
   * reposition item stype
   * @param {date} start
   * @param {date} end
   */
  repositionStype(start, end) {
    this.dom.line.style.display = 'block';
    this.dom.dot.style.display = 'block';
    const lineOffsetWidth = this.dom.line.offsetWidth;
    const dotOffsetWidth = this.dom.dot.offsetWidth;

    if (end) {
      const lineOffset = lineOffsetWidth + start + (end - start) / 2;
      const dotOffset = lineOffset - dotOffsetWidth / 2;
      const lineOffsetDirection = this.options.rtl ? lineOffset * -1 : lineOffset;
      const dotOffsetDirection = this.options.rtl ? dotOffset * -1 : dotOffset;

      this.dom.line.style.transform = `translateX(${lineOffsetDirection}px)`;
      this.dom.dot.style.transform = `translateX(${dotOffsetDirection}px)`;
    } else {
      const lineOffsetDirection = this.options.rtl ? (start * -1) : start;
      const dotOffsetDirection = this.options.rtl ? ((start - dotOffsetWidth / 2) * -1) : (start - dotOffsetWidth / 2);

      this.dom.line.style.transform = `translateX(${lineOffsetDirection}px)`;
      this.dom.dot.style.transform = `translateX(${dotOffsetDirection}px)`;
    }
  }
  
  /**
   * reposition x without ranges
   * @param {date} start
   * @param {string} align
   */
  repositionXWithoutRanges(start, align) {
    // calculate left position of the box
    if (align == 'right') {
      if (this.options.rtl) {
        this.right = start - this.width;
  
        // reposition box, line, and dot
        this.dom.box.style.right = this.right + 'px';
      } else {
        this.left = start - this.width;
  
        // reposition box, line, and dot
        this.dom.box.style.left = this.left + 'px';
      }
    } else if (align == 'left') {
      if (this.options.rtl) {
        this.right = start;
  
        // reposition box, line, and dot
        this.dom.box.style.right = this.right + 'px';
      } else {
        this.left = start;
  
        // reposition box, line, and dot
        this.dom.box.style.left = this.left + 'px';
      }
    } else {
      // default or 'center'
      if (this.options.rtl) {
        this.right = start - this.width / 2;
  
        // reposition box, line, and dot
        this.dom.box.style.right = this.right + 'px';
      } else {
        this.left = start - this.width / 2;
  
        // reposition box, line, and dot
        this.dom.box.style.left = this.left + 'px';
      }
    }
  }
  
  /**
   * reposition x with ranges
   * @param {date} start
   * @param {date} end
   */
  repositionXWithRanges(start, end) {
    let boxWidth = Math.round(Math.max(end - start + 0.5, 1));
  
    if (this.options.rtl) {
      this.right = start;
    } else {
      this.left = start;
    }
  
    this.width = Math.max(boxWidth, this.minWidth || 0);
  
    if (this.options.rtl) {
      this.dom.box.style.right = this.right + 'px';
    } else {
      this.dom.box.style.left = this.left + 'px';
    }
  
    this.dom.box.style.width = boxWidth + 'px';
  }
  
  /**
   * reposition item y axis
   */
  repositionY() {
    var orientation = this.options.orientation.item;
    var box = this.dom.box;
    if (orientation == 'top') {
      box.style.top = (this.top || 0) + 'px';
    } else { 
      // orientation 'bottom'
      box.style.top = (this.parent.height - this.top - this.height || 0) + 'px';
    }
  
    if (this.options.showStipes) {
      if (orientation == 'top') {
        this.dom.line.style.top    = '0';
        this.dom.line.style.height = (this.parent.top + this.top + 1) + 'px';
        this.dom.line.style.bottom = '';
      }
      else { 
        // orientation 'bottom'
        var itemSetHeight = this.parent.itemSet.props.height;
        var lineHeight = itemSetHeight - this.parent.top - this.parent.height + this.top;
        this.dom.line.style.top    = (itemSetHeight - lineHeight) + 'px';
        this.dom.line.style.bottom = '0';
      }
    
      this.dom.dot.style.top = (-this.dom.dot.offsetHeight / 2) + 'px';
    }
  }

  /**
   * get width left
   * @return {number}
   */
  getWidthLeft() {
    return this.width / 2;
  }
  
  /**
   * get width right
   * @return {number}
   */
  getWidthRight() {
    return this.width / 2;
  }
  
  /**
   * move cluster item
   */
  move() {
    this.repositionX();
    this.repositionY();
  }
  
  /**
   * attach
   */
  attach() {
    for (let item of this.data.uiItems) {
      item.cluster = this;
    }
  
    this.data.items = this.data.uiItems.map(item => item.data);

    this.attached = true;
    this.dirty = true;
  }
  
  /**
   * detach
   * @param {boolean} detachFromParent
   * @return {void}
   */
  detach(detachFromParent = false) {
    if (!this.hasItems()) {
      return;
    }
  
    for (let item of this.data.uiItems) {
      delete item.cluster;
    }
  
    this.attached = false;
  
    if (detachFromParent && this.group) {
      this.group.remove(this);
      this.group = null;
    }
  
    this.data.items = [];
    this.dirty = true;
  }
  
  /**
   * handle on double click
   */
  _onDoubleClick() {
   this._fit();
  }
  
  /**
   * set range
   */
  _setupRange() {
    const stats = this.data.uiItems.map(item => ({
      start: item.data.start.valueOf(),
      end: item.data.end ? item.data.end.valueOf() : item.data.start.valueOf(),
    }));
  
    this.data.min = Math.min(...stats.map(s => Math.min(s.start, s.end || s.start)));
    this.data.max = Math.max(...stats.map(s => Math.max(s.start, s.end || s.start)));
    const centers = this.data.uiItems.map(item => item.center);
    const avg = centers.reduce((sum, value) => sum + value, 0) / this.data.uiItems.length;
  
    if (this.data.uiItems.some(item => item.data.end)) {
      // contains ranges
      this.data.start = new Date(this.data.min);
      this.data.end = new Date(this.data.max);
    } else {
      this.data.start = new Date(avg);
      this.data.end = null;
    }
  }
  
  /**
   * get UI items
   * @return {array}
   */
  _getUiItems() {
    if (this.data.uiItems && this.data.uiItems.length) {
      return this.data.uiItems.filter(item => item.cluster === this);
    }
  
    return [];
  }
  
  /**
   * create DOM element
   */
  _createDomElement() {
    if (!this.dom) {
      // create DOM
      this.dom = {};
  
      // create main box
      this.dom.box = document.createElement('DIV');
  
      // contents box (inside the background box). used for making margins
      this.dom.content = document.createElement('DIV');
      this.dom.content.className = 'vis-item-content';
      
      this.dom.box.appendChild(this.dom.content);
  
      if (this.options.showStipes) {
        // line to axis
        this.dom.line = document.createElement('DIV');
        this.dom.line.className = 'vis-cluster-line';
        this.dom.line.style.display = 'none';
  
        // dot on axis
        this.dom.dot = document.createElement('DIV');
        this.dom.dot.className = 'vis-cluster-dot';
        this.dom.dot.style.display = 'none';
      }
  
      if (this.options.fitOnDoubleClick) {
        this.dom.box.ondblclick = ClusterItem.prototype._onDoubleClick.bind(this);
      }
      
      // attach this item as attribute
      this.dom.box['vis-item'] = this;
  
      this.dirty = true;
    }
  }
  
  /**
   * append element to DOM
   */
  _appendDomElement() {
    if (!this.parent) {
      throw new Error('Cannot redraw item: no parent attached');
    }
  
    if (!this.dom.box.parentNode) {
      const foreground = this.parent.dom.foreground;
      if (!foreground) {
        throw new Error('Cannot redraw item: parent has no foreground container element');
      }
  
      foreground.appendChild(this.dom.box);
    }
  
    const background = this.parent.dom.background;
  
    if (this.options.showStipes) {
      if (!this.dom.line.parentNode) {
        if (!background) throw new Error('Cannot redraw item: parent has no background container element');
        background.appendChild(this.dom.line);
      }
    
      if (!this.dom.dot.parentNode) {
        var axis = this.parent.dom.axis;
        if (!background) throw new Error('Cannot redraw item: parent has no axis container element');
        axis.appendChild(this.dom.dot);
      }
    }
  
    this.displayed = true;
  }
  
  /**
   * update dirty DOM components
   */
  _updateDirtyDomComponents() {
    // An item is marked dirty when:
    // - the item is not yet rendered
    // - the item's data is changed
    // - the item is selected/deselected
    if (this.dirty) {
      this._updateContents(this.dom.content);
      this._updateDataAttributes(this.dom.box);
      this._updateStyle(this.dom.box);
  
      // update class
      const className = this.baseClassName + ' ' + (this.data.className ? ' ' + this.data.className : '') +
        (this.selected ? ' vis-selected' : '') + ' vis-readonly';
      this.dom.box.className = 'vis-item ' + className;
  
      if (this.options.showStipes) {
        this.dom.line.className = 'vis-item vis-cluster-line ' +  (this.selected ? ' vis-selected' : '');
        this.dom.dot.className  = 'vis-item vis-cluster-dot ' +  (this.selected ? ' vis-selected' : '');
      }
  
      if (this.data.end) {
        // turn off max-width to be able to calculate the real width
        // this causes an extra browser repaint/reflow, but so be it
        this.dom.content.style.maxWidth = 'none';
      }
    }
  }
  
  /**
   * get DOM components sizes
   * @return {object}
   */
  _getDomComponentsSizes() {
    const sizes = {
      previous: {
        right: this.dom.box.style.right,
        left: this.dom.box.style.left
      },
      box: {
        width: this.dom.box.offsetWidth,
        height: this.dom.box.offsetHeight
      },
    };

    if (this.options.showStipes) {
      sizes.dot = {
        height: this.dom.dot.offsetHeight,
        width: this.dom.dot.offsetWidth
      };
      sizes.line = {
        width: this.dom.line.offsetWidth
      };
    }

    return sizes;
  }
  
  /**
   * update DOM components sizes
   * @param {object} sizes
   */
  _updateDomComponentsSizes(sizes) {
    if (this.options.rtl) {
      this.dom.box.style.right = "0px";
    } else {
      this.dom.box.style.left = "0px";
    }
  
    // recalculate size
    if (!this.data.end) {
      this.width = sizes.box.width;
    } else {
      this.minWidth = sizes.box.width;
    }
  
    this.height = sizes.box.height;
  
    // restore previous position
    if (this.options.rtl) {
      this.dom.box.style.right = sizes.previous.right;
    } else {
      this.dom.box.style.left = sizes.previous.left;
    }
  
    this.dirty = false;
  }
  
  /**
   * repaint DOM additional components
   */
  _repaintDomAdditionals() {
    this._repaintOnItemUpdateTimeTooltip(this.dom.box);
  }
  
  /**
   * check is stripe visible
   * @return {number}
   * @private
   */
  _isStipeVisible() {
    return this.minWidth >= this.width || !this.data.end;
  }
  
  /**
   * get fit range
   * @return {object}
   * @private
   */
  _getFitRange() {
    const offset = 0.05*(this.data.max - this.data.min) / 2;
      return {
        fitStart: this.data.min - offset,
        fitEnd: this.data.max + offset
      };
  }
  
   /**
   * fit
   * @private
   */
  _fit() {
    if (this.emitter) {
      const {fitStart, fitEnd} = this._getFitRange();
  
      const fitArgs = {
        start: new Date(fitStart),
        end: new Date(fitEnd),
        animation: true
      };
  
      this.emitter.emit('fit', fitArgs);
    }
  }

   /**
   * get item data
   * @return {object}
   * @private
   */
  _getItemData() {
    return this.data;
  }
}

ClusterItem.prototype.baseClassName = 'vis-item vis-range vis-cluster';

const UNGROUPED$1 = '__ungrouped__';   // reserved group id for ungrouped items
const BACKGROUND$1 = '__background__'; // reserved group id for background items without group

const ReservedGroupIds$1 = {
  UNGROUPED: UNGROUPED$1,
  BACKGROUND: BACKGROUND$1
};

/**
 * An Cluster generator generates cluster items
 */
class ClusterGenerator {
    /**
     * @param {ItemSet} itemSet itemsSet instance
     * @constructor ClusterGenerator
    */
    constructor(itemSet) {
        this.itemSet = itemSet;
        this.groups = {};
        this.cache = {};
        this.cache[-1] = [];
    }

    /**
     * @param {Object} itemData             Object containing parameters start content, className.
     * @param {{toScreen: function, toTime: function}} conversion
     *                                  Conversion functions from time to screen and vice versa
     * @param {Object} [options]        Configuration options
     * @return {Object} newItem
    */
    createClusterItem(itemData, conversion, options) {
        const newItem = new ClusterItem(itemData, conversion, options);
        return newItem;
    }

    /**
     * Set the items to be clustered.
     * This will clear cached clusters.
     * @param {Item[]} items
     * @param {Object} [options]  Available options:
     *                            {boolean} applyOnChangedLevel
     *                                If true (default), the changed data is applied
     *                                as soon the cluster level changes. If false,
     *                                The changed data is applied immediately
     */
    setItems(items, options) {
        this.items = items || [];
        this.dataChanged = true;
        this.applyOnChangedLevel = false;

        if (options && options.applyOnChangedLevel) {
            this.applyOnChangedLevel = options.applyOnChangedLevel;
        }
    }

    /**
     * Update the current data set: clear cache, and recalculate the clustering for
     * the current level
     */
    updateData() {
        this.dataChanged = true;
        this.applyOnChangedLevel = false;
    }

    /**
     * Cluster the items which are too close together
     * @param {array} oldClusters 
     * @param {number} scale      The scale of the current window : (windowWidth / (endDate - startDate)) 
     * @param {{maxItems: number, clusterCriteria: function, titleTemplate: string}} options             
     * @return {array} clusters
    */
    getClusters(oldClusters, scale, options) {
        let { maxItems, clusterCriteria } = typeof options === "boolean" ? {} : options;
    
        if (!clusterCriteria) {
            clusterCriteria = () => true;
        }

        maxItems = maxItems || 1;

        let level = -1;
        let granularity = 2;
        let timeWindow = 0;

        if (scale > 0) {
            if (scale >= 1) {
                return [];
            }

            level = Math.abs(Math.round(Math.log(100 / scale) / Math.log(granularity)));
            timeWindow = Math.abs(Math.pow(granularity, level));
        }

        // clear the cache when and re-generate groups the data when needed.
        if (this.dataChanged) {
            const levelChanged = (level != this.cacheLevel);
            const applyDataNow = this.applyOnChangedLevel ? levelChanged : true;
            if (applyDataNow) {
                this._dropLevelsCache();
                this._filterData();
            }
        }

        this.cacheLevel = level;
        let clusters = this.cache[level];
        if (!clusters) {
            clusters = [];
            for (let groupName in this.groups) {
                if (this.groups.hasOwnProperty(groupName)) {
                    const items = this.groups[groupName];
                    const iMax = items.length;
                    let i = 0;
                    while (i < iMax) {
                        // find all items around current item, within the timeWindow
                        let item = items[i];
                        let neighbors = 1; // start at 1, to include itself)

                        // loop through items left from the current item
                        let j = i - 1;
                        while (j >= 0 && (item.center - items[j].center) < timeWindow / 2) {
                            if (!items[j].cluster && clusterCriteria(item.data, items[j].data)) {
                                neighbors++;
                            }
                            j--;
                        }

                        // loop through items right from the current item
                        let k = i + 1;
                        while (k < items.length && (items[k].center - item.center) < timeWindow / 2) {
                            if (clusterCriteria(item.data, items[k].data)) {
                                neighbors++;
                            }
                            k++;
                        }

                        // loop through the created clusters
                        let l = clusters.length - 1;
                        while (l >= 0 && (item.center - clusters[l].center) < timeWindow) {
                            if (item.group == clusters[l].group && clusterCriteria(item.data, clusters[l].data)) {
                                neighbors++;
                            }
                            l--;
                        }

                        // aggregate until the number of items is within maxItems
                        if (neighbors > maxItems) {
                            // too busy in this window.
                            const num = neighbors - maxItems + 1;
                            const clusterItems = [];

                            // append the items to the cluster,
                            // and calculate the average start for the cluster
                            let m = i;
                            while (clusterItems.length < num && m < items.length) {
                                if (clusterCriteria(items[i].data, items[m].data)) {
                                    clusterItems.push(items[m]);
                                }
                                m++;
                            }

                            const groupId = this.itemSet.getGroupId(item.data);
                            const group = this.itemSet.groups[groupId] || this.itemSet.groups[ReservedGroupIds$1.UNGROUPED];
                            let cluster = this._getClusterForItems(clusterItems, group, oldClusters, options);
                            clusters.push(cluster);

                            i += num;
                        } else {
                            delete item.cluster;
                            i += 1;
                        }
                    }
                }
            }

            this.cache[level] = clusters;
        }

        return clusters;
    }

    /**
     * Filter the items per group.
     * @private
     */
    _filterData() {
        // filter per group
        const groups = {};
        this.groups = groups;

        // split the items per group
        for (const item of Object.values(this.items)) {
            // put the item in the correct group
            const groupName = item.parent ? item.parent.groupId : '';
            let group = groups[groupName];
            if (!group) {
                group = [];
                groups[groupName] = group;
            }
            group.push(item);

            // calculate the center of the item
            if (item.data.start) {
                if (item.data.end) {
                    // range
                    item.center = (item.data.start.valueOf() + item.data.end.valueOf()) / 2;
                } else {
                    // box, dot
                    item.center = item.data.start.valueOf();
                }
            }
        }

        // sort the items per group
        for (let currentGroupName in groups) {
            if (groups.hasOwnProperty(currentGroupName)) {
                groups[currentGroupName].sort((a, b) => a.center - b.center);
            }
        }

        this.dataChanged = false;
    }

    /**
     * Create new cluster or return existing
     * @private
     * @param {array} clusterItems    
     * @param {object} group 
     * @param {array} oldClusters 
     * @param {object} options 
     * @returns {object} cluster
     */
    _getClusterForItems(clusterItems, group, oldClusters, options) {
        const oldClustersLookup = (oldClusters || []).map(cluster => ({
            cluster,
            itemsIds: new Set(cluster.data.uiItems.map(item => item.id))
        }));
        let cluster;
        if (oldClustersLookup.length) {
            for (let oldClusterData of oldClustersLookup) {
                if (oldClusterData.itemsIds.size === clusterItems.length 
                    && clusterItems.every(clusterItem => oldClusterData.itemsIds.has(clusterItem.id))) {
                    cluster = oldClusterData.cluster;
                    break;
                }
            }
        }

        if (cluster) {
            cluster.setUiItems(clusterItems);
            if (cluster.group !== group) {
                if (cluster.group) {
                    cluster.group.remove(cluster);    
                }

                if (group) {
                    group.add(cluster);    
                    cluster.group = group;
                }
            }
            return cluster;
        }

        let titleTemplate = options.titleTemplate || '';
        const conversion = {
            toScreen: this.itemSet.body.util.toScreen,
            toTime: this.itemSet.body.util.toTime
        };

        const title = titleTemplate.replace(/{count}/, clusterItems.length);
        const clusterContent = '<div title="' + title + '">' + clusterItems.length + '</div>';
        const clusterOptions = Object.assign({}, options, this.itemSet.options);
        const data = {
            'content': clusterContent,
            'title': title,
            'group': group,
            'uiItems': clusterItems,
            'eventEmitter': this.itemSet.body.emitter,
            'range': this.itemSet.body.range
        };
        cluster = this.createClusterItem(data,
        conversion,
        clusterOptions);

        if (group) {
            group.add(cluster);
            cluster.group = group;
        }

        cluster.attach();

        return cluster;
    }

    /**
     * Drop cache
     * @private
     */
    _dropLevelsCache() {
        this.cache = {};
        this.cacheLevel = -1;
        this.cache[this.cacheLevel] = [];
    }
}

const UNGROUPED$2 = '__ungrouped__';   // reserved group id for ungrouped items
const BACKGROUND$2 = '__background__'; // reserved group id for background items without group

/**
 * An ItemSet holds a set of items and ranges which can be displayed in a
 * range. The width is determined by the parent of the ItemSet, and the height
 * is determined by the size of the items.
 */
class ItemSet extends Component {
  /**
 * @param {{dom: Object, domProps: Object, emitter: Emitter, range: Range}} body
 * @param {Object} [options]      See ItemSet.setOptions for the available options.
 * @constructor ItemSet
 * @extends Component
 */
  constructor(body, options) {
    super();
    this.body = body;
    this.defaultOptions = {
      type: null,  // 'box', 'point', 'range', 'background'
      orientation: {
        item: 'bottom'   // item orientation: 'top' or 'bottom'
      },
      align: 'auto', // alignment of box items
      stack: true,
      stackSubgroups: true,
      groupOrderSwap(fromGroup, toGroup, groups) {  // eslint-disable-line no-unused-vars
        const targetOrder = toGroup.order;
        toGroup.order = fromGroup.order;
        fromGroup.order = targetOrder;
      },
      groupOrder: 'order',

      selectable: true,
      multiselect: false,
      longSelectPressTime: 251,
      itemsAlwaysDraggable: {
        item: false,
        range: false,
      },

      editable: {
        updateTime: false,
        updateGroup: false,
        add: false,
        remove: false,
        overrideItems: false
      },

      groupEditable: {
        order: false,
        add: false,
        remove: false
      },

      snap: TimeStep.snap,

      // Only called when `objectData.target === 'item'.
      onDropObjectOnItem(objectData, item, callback) {
        callback(item);
      },
      onAdd(item, callback) {
        callback(item);
      },
      onUpdate(item, callback) {
        callback(item);
      },
      onMove(item, callback) {
        callback(item);
      },
      onRemove(item, callback) {
        callback(item);
      },
      onMoving(item, callback) {
        callback(item);
      },
      onAddGroup(item, callback) {
        callback(item);
      },
      onMoveGroup(item, callback) {
        callback(item);
      },
      onRemoveGroup(item, callback) {
        callback(item);
      },

      margin: {
        item: {
          horizontal: 10,
          vertical: 10
        },
        axis: 20
      },

      showTooltips: true,

      tooltip: {
        followMouse: false,
        overflowMethod: 'flip',
        delay: 500
      },

      tooltipOnItemUpdateTime: false
    };

    // options is shared by this ItemSet and all its items
    this.options = util$3.extend({}, this.defaultOptions);
    this.options.rtl = options.rtl;
    this.options.onTimeout = options.onTimeout;

    this.conversion = {
      toScreen: body.util.toScreen,
      toTime: body.util.toTime
    };
    this.dom = {};
    this.props = {};
    this.hammer = null;
    
    const me = this;
    this.itemsData = null;    // DataSet
    this.groupsData = null;   // DataSet
    this.itemsSettingTime = null;
    this.initialItemSetDrawn = false;
    this.userContinueNotBail = null;  

    this.sequentialSelection = false;
    
    // listeners for the DataSet of the items
    this.itemListeners = {
      'add'(event, params, senderId) {  // eslint-disable-line no-unused-vars
        me._onAdd(params.items);
        if (me.options.cluster) {
          me.clusterGenerator.setItems(me.items, { applyOnChangedLevel: false });
        }
        me.redraw();
      },
      'update'(event, params, senderId) {  // eslint-disable-line no-unused-vars
        me._onUpdate(params.items);
        if (me.options.cluster) {
          me.clusterGenerator.setItems(me.items, { applyOnChangedLevel: false });
        }
        me.redraw();
      },
      'remove'(event, params, senderId) {  // eslint-disable-line no-unused-vars
        me._onRemove(params.items);
        if (me.options.cluster) {
          me.clusterGenerator.setItems(me.items, { applyOnChangedLevel: false });
        }
        me.redraw();
      }
    };

    // listeners for the DataSet of the groups
    this.groupListeners = {
      'add'(event, params, senderId) {  // eslint-disable-line no-unused-vars
        me._onAddGroups(params.items);
        
        if (me.groupsData && me.groupsData.length > 0) {
            const groupsData = me.groupsData.getDataSet();
            groupsData.get().forEach(groupData => {
            if (groupData.nestedGroups) {
              if (groupData.showNested != false) {
                groupData.showNested = true;
              }
              let updatedGroups = [];
              groupData.nestedGroups.forEach(nestedGroupId => {
                const updatedNestedGroup = groupsData.get(nestedGroupId);
                if (!updatedNestedGroup) { return; }
                updatedNestedGroup.nestedInGroup = groupData.id;
                if (groupData.showNested == false) {
                  updatedNestedGroup.visible = false;
                }
                updatedGroups = updatedGroups.concat(updatedNestedGroup);
              });
              groupsData.update(updatedGroups, senderId);
            }
          });
        }
      },
      'update'(event, params, senderId) {  // eslint-disable-line no-unused-vars
        me._onUpdateGroups(params.items);
      },
      'remove'(event, params, senderId) {  // eslint-disable-line no-unused-vars
        me._onRemoveGroups(params.items);
      }
    };

    this.items = {};      // object with an Item for every data item
    this.groups = {};     // Group object for every group
    this.groupIds = [];

    this.selection = [];  // list with the ids of all selected nodes

    this.popup = null;
    this.popupTimer = null;

    this.touchParams = {}; // stores properties while dragging
    this.groupTouchParams = {
      group: null,
      isDragging: false
    };
  
    // create the HTML DOM
    this._create();

    this.setOptions(options);
    this.clusters = [];
  }

  /**
   * Create the HTML DOM for the ItemSet
   */
  _create() {
    const frame = document.createElement('div');
    frame.className = 'vis-itemset';
    frame['vis-itemset'] = this;
    this.dom.frame = frame;

    // create background panel
    const background = document.createElement('div');
    background.className = 'vis-background';
    frame.appendChild(background);
    this.dom.background = background;

    // create foreground panel
    const foreground = document.createElement('div');
    foreground.className = 'vis-foreground';
    frame.appendChild(foreground);
    this.dom.foreground = foreground;

    // create axis panel
    const axis = document.createElement('div');
    axis.className = 'vis-axis';
    this.dom.axis = axis;

    // create labelset
    const labelSet = document.createElement('div');
    labelSet.className = 'vis-labelset';
    this.dom.labelSet = labelSet;

    // create ungrouped Group
    this._updateUngrouped();

    // create background Group
    const backgroundGroup = new BackgroundGroup(BACKGROUND$2, null, this);
    backgroundGroup.show();
    this.groups[BACKGROUND$2] = backgroundGroup;

    // attach event listeners
    // Note: we bind to the centerContainer for the case where the height
    //       of the center container is larger than of the ItemSet, so we
    //       can click in the empty area to create a new item or deselect an item.
    this.hammer = new Hammer$2(this.body.dom.centerContainer);

    // drag items when selected
    this.hammer.on('hammer.input', event => {
      if (event.isFirst) {
        this._onTouch(event);
      }
    });
    this.hammer.on('panstart', this._onDragStart.bind(this));
    this.hammer.on('panmove',  this._onDrag.bind(this));
    this.hammer.on('panend',   this._onDragEnd.bind(this));
    this.hammer.get('pan').set({threshold:5, direction: Hammer$2.ALL});

    // single select (or unselect) when tapping an item
    this.hammer.on('tap',  this._onSelectItem.bind(this));

    // multi select when holding mouse/touch, or on ctrl+click
    this.hammer.on('press', this._onMultiSelectItem.bind(this));

    // add item on doubletap
    this.hammer.on('doubletap', this._onAddItem.bind(this));

    if (this.options.rtl) {
      this.groupHammer = new Hammer$2(this.body.dom.rightContainer);
    } else {
      this.groupHammer = new Hammer$2(this.body.dom.leftContainer);
    }
    
    this.groupHammer.on('tap',      this._onGroupClick.bind(this));
    this.groupHammer.on('panstart', this._onGroupDragStart.bind(this));
    this.groupHammer.on('panmove',  this._onGroupDrag.bind(this));
    this.groupHammer.on('panend',   this._onGroupDragEnd.bind(this));
    this.groupHammer.get('pan').set({threshold:5, direction: Hammer$2.DIRECTION_VERTICAL});
    
    this.body.dom.centerContainer.addEventListener('mouseover', this._onMouseOver.bind(this));
    this.body.dom.centerContainer.addEventListener('mouseout', this._onMouseOut.bind(this));
    this.body.dom.centerContainer.addEventListener('mousemove', this._onMouseMove.bind(this));
    // right-click on timeline 
    this.body.dom.centerContainer.addEventListener('contextmenu', this._onDragEnd.bind(this));

    this.body.dom.centerContainer.addEventListener('mousewheel', this._onMouseWheel.bind(this));

    // attach to the DOM
    this.show();
  }

  /**
   * Set options for the ItemSet. Existing options will be extended/overwritten.
   * @param {Object} [options] The following options are available:
   *                           {string} type
   *                              Default type for the items. Choose from 'box'
   *                              (default), 'point', 'range', or 'background'.
   *                              The default style can be overwritten by
   *                              individual items.
   *                           {string} align
   *                              Alignment for the items, only applicable for
   *                              BoxItem. Choose 'center' (default), 'left', or
   *                              'right'.
   *                           {string} orientation.item
   *                              Orientation of the item set. Choose 'top' or
   *                              'bottom' (default).
   *                           {Function} groupOrder
   *                              A sorting function for ordering groups
   *                           {boolean} stack
   *                              If true (default), items will be stacked on
   *                              top of each other.
   *                           {number} margin.axis
   *                              Margin between the axis and the items in pixels.
   *                              Default is 20.
   *                           {number} margin.item.horizontal
   *                              Horizontal margin between items in pixels.
   *                              Default is 10.
   *                           {number} margin.item.vertical
   *                              Vertical Margin between items in pixels.
   *                              Default is 10.
   *                           {number} margin.item
   *                              Margin between items in pixels in both horizontal
   *                              and vertical direction. Default is 10.
   *                           {number} margin
   *                              Set margin for both axis and items in pixels.
   *                           {boolean} selectable
   *                              If true (default), items can be selected.
   *                           {boolean} multiselect
   *                              If true, multiple items can be selected.
   *                              False by default.
   *                           {boolean} editable
   *                              Set all editable options to true or false
   *                           {boolean} editable.updateTime
   *                              Allow dragging an item to an other moment in time
   *                           {boolean} editable.updateGroup
   *                              Allow dragging an item to an other group
   *                           {boolean} editable.add
   *                              Allow creating new items on double tap
   *                           {boolean} editable.remove
   *                              Allow removing items by clicking the delete button
   *                              top right of a selected item.
   *                           {Function(item: Item, callback: Function)} onAdd
   *                              Callback function triggered when an item is about to be added:
   *                              when the user double taps an empty space in the Timeline.
   *                           {Function(item: Item, callback: Function)} onUpdate
   *                              Callback function fired when an item is about to be updated.
   *                              This function typically has to show a dialog where the user
   *                              change the item. If not implemented, nothing happens.
   *                           {Function(item: Item, callback: Function)} onMove
   *                              Fired when an item has been moved. If not implemented,
   *                              the move action will be accepted.
   *                           {Function(item: Item, callback: Function)} onRemove
   *                              Fired when an item is about to be deleted.
   *                              If not implemented, the item will be always removed.
   */
  setOptions(options) {
    if (options) {
      // copy all options that we know
      const fields = [
        'type', 'rtl', 'align', 'order', 'stack', 'stackSubgroups', 'selectable', 'multiselect', 'sequentialSelection',
        'multiselectPerGroup', 'longSelectPressTime', 'groupOrder', 'dataAttributes', 'template', 'groupTemplate', 'visibleFrameTemplate',
        'hide', 'snap', 'groupOrderSwap', 'showTooltips', 'tooltip', 'tooltipOnItemUpdateTime', 'groupHeightMode', 'onTimeout'
      ];
      util$3.selectiveExtend(fields, this.options, options);

      if ('itemsAlwaysDraggable' in options) {
        if (typeof options.itemsAlwaysDraggable === 'boolean') {
          this.options.itemsAlwaysDraggable.item = options.itemsAlwaysDraggable;
          this.options.itemsAlwaysDraggable.range = false;
        }
        else if (typeof options.itemsAlwaysDraggable === 'object') {
          util$3.selectiveExtend(['item', 'range'], this.options.itemsAlwaysDraggable, options.itemsAlwaysDraggable);
          // only allow range always draggable when item is always draggable as well
          if (! this.options.itemsAlwaysDraggable.item) {
            this.options.itemsAlwaysDraggable.range = false;
          }
        }
      }

      if ('sequentialSelection' in options) {
        if (typeof options.sequentialSelection === 'boolean') {
          this.options.sequentialSelection = options.sequentialSelection;
        }
      }

      if ('orientation' in options) {
        if (typeof options.orientation === 'string') {
          this.options.orientation.item = options.orientation === 'top' ? 'top' : 'bottom';
        }
        else if (typeof options.orientation === 'object' && 'item' in options.orientation) {
          this.options.orientation.item = options.orientation.item;
        }
      }

      if ('margin' in options) {
        if (typeof options.margin === 'number') {
          this.options.margin.axis = options.margin;
          this.options.margin.item.horizontal = options.margin;
          this.options.margin.item.vertical = options.margin;
        }
        else if (typeof options.margin === 'object') {
          util$3.selectiveExtend(['axis'], this.options.margin, options.margin);
          if ('item' in options.margin) {
            if (typeof options.margin.item === 'number') {
              this.options.margin.item.horizontal = options.margin.item;
              this.options.margin.item.vertical = options.margin.item;
            }
            else if (typeof options.margin.item === 'object') {
              util$3.selectiveExtend(['horizontal', 'vertical'], this.options.margin.item, options.margin.item);
            }
          }
        }
      }

      ['locale', 'locales'].forEach(key => {
        if (key in options) {
          this.options[key] = options[key];
        }
      });

      if ('editable' in options) {
        if (typeof options.editable === 'boolean') {
          this.options.editable.updateTime    = options.editable;
          this.options.editable.updateGroup   = options.editable;
          this.options.editable.add           = options.editable;
          this.options.editable.remove        = options.editable;
          this.options.editable.overrideItems = false;
        }
        else if (typeof options.editable === 'object') {
          util$3.selectiveExtend(['updateTime', 'updateGroup', 'add', 'remove', 'overrideItems'], this.options.editable, options.editable);
        }
      }

      if ('groupEditable' in options) {
        if (typeof options.groupEditable === 'boolean') {
          this.options.groupEditable.order  = options.groupEditable;
          this.options.groupEditable.add    = options.groupEditable;
          this.options.groupEditable.remove = options.groupEditable;
        }
        else if (typeof options.groupEditable === 'object') {
          util$3.selectiveExtend(['order', 'add', 'remove'], this.options.groupEditable, options.groupEditable);
        }
      }

      // callback functions
      const addCallback = name => {
        const fn = options[name];
        if (fn) {
          if (!(typeof fn === 'function')) {
            throw new Error(`option ${name} must be a function ${name}(item, callback)`);
          }
          this.options[name] = fn;
        }
      };
      ['onDropObjectOnItem', 'onAdd', 'onUpdate', 'onRemove', 'onMove', 'onMoving', 'onAddGroup', 'onMoveGroup', 'onRemoveGroup'].forEach(addCallback);

      if (options.cluster) {
        Object.assign(this.options, {
          cluster: options.cluster
        });
        if (!this.clusterGenerator) {
          this.clusterGenerator = new ClusterGenerator(this);
        } 
        this.clusterGenerator.setItems(this.items, { applyOnChangedLevel: false });
        this.markDirty({ refreshItems: true, restackGroups: true });

        this.redraw();
      } else if (this.clusterGenerator) {
        this._detachAllClusters();
        this.clusters = [];
        this.clusterGenerator = null;
        this.options.cluster = undefined;
        this.markDirty({ refreshItems: true, restackGroups: true });

        this.redraw();
      } else {
        // force the itemSet to refresh: options like orientation and margins may be changed
        this.markDirty();
      }
    }
  }

  /**
   * Mark the ItemSet dirty so it will refresh everything with next redraw.
   * Optionally, all items can be marked as dirty and be refreshed.
   * @param {{refreshItems: boolean}} [options]
   */
  markDirty(options) {
    this.groupIds = [];

    if (options) {
      if (options.refreshItems) {
        util$3.forEach(this.items, item => {
          item.dirty = true;
          if (item.displayed) item.redraw();
        });
      }
      
      if (options.restackGroups) {
        util$3.forEach(this.groups, (group, key) => {
          if (key === BACKGROUND$2) return;
          group.stackDirty = true;
        });
      }
    }
  }

  /**
   * Destroy the ItemSet
   */
  destroy() {
    this.clearPopupTimer();
    this.hide();
    this.setItems(null);
    this.setGroups(null);

    this.hammer && this.hammer.destroy();
    this.groupHammer && this.groupHammer.destroy();
    this.hammer = null;

    this.body = null;
    this.conversion = null;
  }

  /**
   * Hide the component from the DOM
   */
  hide() {
    // remove the frame containing the items
    if (this.dom.frame.parentNode) {
      this.dom.frame.parentNode.removeChild(this.dom.frame);
    }

    // remove the axis with dots
    if (this.dom.axis.parentNode) {
      this.dom.axis.parentNode.removeChild(this.dom.axis);
    }

    // remove the labelset containing all group labels
    if (this.dom.labelSet.parentNode) {
      this.dom.labelSet.parentNode.removeChild(this.dom.labelSet);
    }
  }

  /**
   * Show the component in the DOM (when not already visible).
   */
  show() {
    // show frame containing the items
    if (!this.dom.frame.parentNode) {
      this.body.dom.center.appendChild(this.dom.frame);
    }

    // show axis with dots
    if (!this.dom.axis.parentNode) {
      this.body.dom.backgroundVertical.appendChild(this.dom.axis);
    }

    // show labelset containing labels
    if (!this.dom.labelSet.parentNode) {
      if (this.options.rtl) {
        this.body.dom.right.appendChild(this.dom.labelSet);
      } else {
        this.body.dom.left.appendChild(this.dom.labelSet);
      }
    }
  }

  /**
   * Activates the popup timer to show the given popup after a fixed time.
   * @param {Popup} popup
   */
  setPopupTimer(popup) {
    this.clearPopupTimer();
    if (popup) {
      const delay = this.options.tooltip.delay || typeof this.options.tooltip.delay === 'number' ?
            this.options.tooltip.delay :
            500;
      this.popupTimer = setTimeout(
        function () {
          popup.show();
        }, delay);
    }
  }

  /**
   * Clears the popup timer for the tooltip.
   */
  clearPopupTimer() {
    if (this.popupTimer != null) {
        clearTimeout(this.popupTimer);
        this.popupTimer = null;
    }
  }
  
  /**
   * Set selected items by their id. Replaces the current selection
   * Unknown id's are silently ignored.
   * @param {string[] | string} [ids] An array with zero or more id's of the items to be
   *                                  selected, or a single item id. If ids is undefined
   *                                  or an empty array, all items will be unselected.
   */
  setSelection(ids) {
    if (ids == undefined) { 
      ids = [];
    }
    
    if (!Array.isArray(ids)) {
      ids = [ids];
    }
  

    const idsToDeselect = this.selection.filter(id => ids.indexOf(id) === -1);

    // unselect currently selected items
    for (let selectedId of idsToDeselect) {
      const item = this.getItemById(selectedId);
      if (item) {
        item.unselect();
      }
    }
  
    // select items
    this.selection = [ ...ids ];
    for (let id of ids) {
      const item = this.getItemById(id);
      if (item) {
        item.select();
      }
    }
  }

  /**
   * Get the selected items by their id
   * @return {Array} ids  The ids of the selected items
   */
  getSelection() {
    return this.selection.concat([]);
  }

  /**
   * Get the id's of the currently visible items.
   * @returns {Array} The ids of the visible items
   */
  getVisibleItems() {
    const range = this.body.range.getRange();
    let right;
    let left;

    if (this.options.rtl) { 
      right  = this.body.util.toScreen(range.start);
      left = this.body.util.toScreen(range.end);
    } else {
      left  = this.body.util.toScreen(range.start);
      right = this.body.util.toScreen(range.end);
    }

    const ids = [];
    for (const groupId in this.groups) {
      if (this.groups.hasOwnProperty(groupId)) {
        const group = this.groups[groupId];
        const rawVisibleItems = group.isVisible ? group.visibleItems : [];

        // filter the "raw" set with visibleItems into a set which is really
        // visible by pixels
        for (const item of rawVisibleItems) {
          // TODO: also check whether visible vertically
          if (this.options.rtl) { 
            if ((item.right < left) && (item.right + item.width > right)) {
              ids.push(item.id);
            }
          } else {
            if ((item.left < right) && (item.left + item.width > left)) {
              ids.push(item.id);
            }
          }
        }
      }
    }

    return ids;
  }

  /**
   * Get the id's of the currently visible groups.
   * @returns {Array} The ids of the visible groups
   */
  getVisibleGroups() {
    const ids = [];

    for (const groupId in this.groups) {
      if (this.groups.hasOwnProperty(groupId)) {
        const group = this.groups[groupId];
        if (group.isVisible) {
          ids.push(groupId);
        }
      }
    }

    return ids;
  }
  
  /**
   * get item by id
   * @param {string} id
   * @return {object} item
   */
  getItemById(id) {
    return this.items[id] || this.clusters.find(cluster => cluster.id === id);
  } 

  /**
   * Deselect a selected item
   * @param {string | number} id
   * @private
   */
  _deselect(id) {
    const selection = this.selection;
    for (let i = 0, ii = selection.length; i < ii; i++) {
      if (selection[i] == id) { // non-strict comparison!
        selection.splice(i, 1);
        break;
      }
    }
  }

  /**
   * Repaint the component
   * @return {boolean} Returns true if the component is resized
   */
  redraw() {
    const margin = this.options.margin;
    const range = this.body.range;
    const asSize = util$3.option.asSize;
    const options = this.options;
    const orientation = options.orientation.item;
    let resized = false;
    const frame = this.dom.frame;

    // recalculate absolute position (before redrawing groups)
    this.props.top = this.body.domProps.top.height + this.body.domProps.border.top;

    if (this.options.rtl) {
      this.props.right = this.body.domProps.right.width + this.body.domProps.border.right;
    } else {
      this.props.left = this.body.domProps.left.width + this.body.domProps.border.left;
    }

    // update class name
    frame.className = 'vis-itemset';

    if (this.options.cluster) {
      this._clusterItems();
    }

    // reorder the groups (if needed)
    resized = this._orderGroups() || resized;

    // check whether zoomed (in that case we need to re-stack everything)
    // TODO: would be nicer to get this as a trigger from Range
    const visibleInterval = range.end - range.start;
    const zoomed = (visibleInterval != this.lastVisibleInterval) || (this.props.width != this.props.lastWidth);
    const scrolled = range.start != this.lastRangeStart;
    const changedStackOption = options.stack != this.lastStack;
    const changedStackSubgroupsOption = options.stackSubgroups != this.lastStackSubgroups;
    const forceRestack = (zoomed || scrolled || changedStackOption || changedStackSubgroupsOption);
    this.lastVisibleInterval = visibleInterval;
    this.lastRangeStart = range.start;
    this.lastStack = options.stack;
    this.lastStackSubgroups = options.stackSubgroups;

    this.props.lastWidth = this.props.width;
    const firstGroup = this._firstGroup();
    const firstMargin = {
      item: margin.item,
      axis: margin.axis
    };
    const nonFirstMargin = {
      item: margin.item,
      axis: margin.item.vertical / 2
    };
    let height = 0;
    const minHeight = margin.axis + margin.item.vertical;

    // redraw the background group
    this.groups[BACKGROUND$2].redraw(range, nonFirstMargin, forceRestack);

    const redrawQueue = {};
    let redrawQueueLength = 0;

    // collect redraw functions
    util$3.forEach(this.groups, (group, key) => {
      if (key === BACKGROUND$2) return;
      const groupMargin = group == firstGroup ? firstMargin : nonFirstMargin;
      const returnQueue = true;
      redrawQueue[key] = group.redraw(range, groupMargin, forceRestack, returnQueue);
      redrawQueueLength = redrawQueue[key].length;
    });

    const needRedraw = redrawQueueLength > 0;
    if (needRedraw) {
      const redrawResults = {};

      for (let i = 0; i < redrawQueueLength; i++) {
        util$3.forEach(redrawQueue, (fns, key) => {
          redrawResults[key] = fns[i]();
        });
      }

      // redraw all regular groups
      util$3.forEach(this.groups, (group, key) => {
        if (key === BACKGROUND$2) return;
        const groupResized = redrawResults[key];
        resized = groupResized || resized;
        height += group.height;
      });
      height = Math.max(height, minHeight);
    }

    height = Math.max(height, minHeight);

    // update frame height
    frame.style.height  = asSize(height);

    // calculate actual size
    this.props.width = frame.offsetWidth;
    this.props.height = height;

    // reposition axis
    this.dom.axis.style.top = asSize((orientation == 'top') ?
        (this.body.domProps.top.height + this.body.domProps.border.top) :
        (this.body.domProps.top.height + this.body.domProps.centerContainer.height));
    if (this.options.rtl) {
      this.dom.axis.style.right = '0';
    } else {
      this.dom.axis.style.left = '0';
    }

    this.hammer.get('press').set({time: this.options.longSelectPressTime});

    this.initialItemSetDrawn = true;
    // check if this component is resized
    resized = this._isResized() || resized;

    return resized;
  }

  /**
   * Get the first group, aligned with the axis
   * @return {Group | null} firstGroup
   * @private
   */
  _firstGroup() {
    const firstGroupIndex = (this.options.orientation.item == 'top') ? 0 : (this.groupIds.length - 1);
    const firstGroupId = this.groupIds[firstGroupIndex];
    const firstGroup = this.groups[firstGroupId] || this.groups[UNGROUPED$2];

    return firstGroup || null;
  }

  /**
   * Create or delete the group holding all ungrouped items. This group is used when
   * there are no groups specified.
   * @protected
   */
  _updateUngrouped() {
    let ungrouped = this.groups[UNGROUPED$2];
    let item;
    let itemId;

    if (this.groupsData) {
      // remove the group holding all ungrouped items
      if (ungrouped) {
        ungrouped.dispose();
        delete this.groups[UNGROUPED$2];

        for (itemId in this.items) {
          if (this.items.hasOwnProperty(itemId)) {
            item = this.items[itemId];
            item.parent && item.parent.remove(item);
            const groupId = this.getGroupId(item.data);
            const group = this.groups[groupId];
            group && group.add(item) || item.hide();
          }
        }
      }
    }
    else {
      // create a group holding all (unfiltered) items
      if (!ungrouped) {
        const id = null;
        const data = null;
        ungrouped = new Group(id, data, this);
        this.groups[UNGROUPED$2] = ungrouped;

        for (itemId in this.items) {
          if (this.items.hasOwnProperty(itemId)) {
            item = this.items[itemId];
            ungrouped.add(item);
          }
        }

        ungrouped.show();
      }
    }
  }

  /**
   * Get the element for the labelset
   * @return {HTMLElement} labelSet
   */
  getLabelSet() {
    return this.dom.labelSet;
  }

  /**
   * Set items
   * @param {vis.DataSet | null} items
   */
  setItems(items) {
    this.itemsSettingTime = new Date();
    const me = this;
    let ids;
    const oldItemsData = this.itemsData;

    // replace the dataset
    if (!items) {
      this.itemsData = null;
    }
    else if (isDataViewLike("id", items)) {
      this.itemsData = typeCoerceDataSet(items);
    }
    else {
      throw new TypeError('Data must implement the interface of DataSet or DataView');
    }

    if (oldItemsData) {
      // unsubscribe from old dataset
      util$3.forEach(this.itemListeners, (callback, event) => {
        oldItemsData.off(event, callback);
      });

      // stop maintaining a coerced version of the old data set
      oldItemsData.dispose();

      // remove all drawn items
      ids = oldItemsData.getIds();
      this._onRemove(ids);
    }

    if (this.itemsData) {
      // subscribe to new dataset
      const id = this.id;
      util$3.forEach(this.itemListeners, (callback, event) => {
        me.itemsData.on(event, callback, id);
      });

      // add all new items
      ids = this.itemsData.getIds();
      this._onAdd(ids);

      // update the group holding all ungrouped items
      this._updateUngrouped();
    }

    this.body.emitter.emit('_change', {queue: true});
  }

  /**
   * Get the current items
   * @returns {vis.DataSet | null}
   */
  getItems() {
    return this.itemsData != null ? this.itemsData.rawDS : null;
  }

  /**
   * Set groups
   * @param {vis.DataSet} groups
   */
  setGroups(groups) {
    const me = this;
    let ids;

    // unsubscribe from current dataset
    if (this.groupsData) {
      util$3.forEach(this.groupListeners, (callback, event) => {
        me.groupsData.off(event, callback);
      });

      // remove all drawn groups
      ids = this.groupsData.getIds();
      this.groupsData = null;
      this._onRemoveGroups(ids); // note: this will cause a redraw
    }

    // replace the dataset
    if (!groups) {
      this.groupsData = null;
    }
    else if (isDataViewLike("id", groups)) {
      this.groupsData = groups;
    }
    else {
      throw new TypeError('Data must implement the interface of DataSet or DataView');
    }

    if (this.groupsData) {
      // go over all groups nesting
      const groupsData = this.groupsData.getDataSet();

      groupsData.get().forEach(group => {
        if (group.nestedGroups) {
          group.nestedGroups.forEach(nestedGroupId => {
            const updatedNestedGroup = groupsData.get(nestedGroupId);
            updatedNestedGroup.nestedInGroup = group.id;
            if (group.showNested == false) {
              updatedNestedGroup.visible = false;
            }
            groupsData.update(updatedNestedGroup);
          });
        }
      });

      // subscribe to new dataset
      const id = this.id;
      util$3.forEach(this.groupListeners, (callback, event) => {
        me.groupsData.on(event, callback, id);
      });

      // draw all ms
      ids = this.groupsData.getIds();
      this._onAddGroups(ids);
    }

    // update the group holding all ungrouped items
    this._updateUngrouped();

    // update the order of all items in each group
    this._order();

    if (this.options.cluster) {
      this.clusterGenerator.updateData();
      this._clusterItems();
      this.markDirty({ refreshItems: true, restackGroups: true });
    }

    this.body.emitter.emit('_change', {queue: true});
  }

  /**
   * Get the current groups
   * @returns {vis.DataSet | null} groups
   */
  getGroups() {
    return this.groupsData;
  }

  /**
   * Remove an item by its id
   * @param {string | number} id
   */
  removeItem(id) {
    const item = this.itemsData.get(id);

    if (item) {
      // confirm deletion
      this.options.onRemove(item, item => {
        if (item) {
          // remove by id here, it is possible that an item has no id defined
          // itself, so better not delete by the item itself
          this.itemsData.remove(id);
        }
      });
    }
  }

  /**
   * Get the time of an item based on it's data and options.type
   * @param {Object} itemData
   * @returns {string} Returns the type
   * @private
   */
  _getType(itemData) {
    return itemData.type || this.options.type || (itemData.end ? 'range' : 'box');
  }

  /**
   * Get the group id for an item
   * @param {Object} itemData
   * @returns {string} Returns the groupId
   * @private
   */
  getGroupId(itemData) {
    const type = this._getType(itemData);
    if (type == 'background' && itemData.group == undefined) {
     return BACKGROUND$2;
    }
    else {
      return this.groupsData ? itemData.group : UNGROUPED$2;
    }
  }

  /**
   * Handle updated items
   * @param {number[]} ids
   * @protected
   */
  _onUpdate(ids) {
    const me = this;

    ids.forEach(id => {
      const itemData = me.itemsData.get(id);
      let item = me.items[id];
      const type = itemData ? me._getType(itemData) : null;

      const constructor = ItemSet.types[type];
      let selected;

      if (item) {
        // update item   	
        if (!constructor || !(item instanceof constructor)) {
          // item type has changed, delete the item and recreate it
          selected = item.selected; // preserve selection of this item
          me._removeItem(item);
          item = null;
        }
        else {
          me._updateItem(item, itemData);
        }
      }

      if (!item && itemData) {
        // create item
        if (constructor) {
          item = new constructor(itemData, me.conversion, me.options);
          item.id = id; // TODO: not so nice setting id afterwards

          me._addItem(item);
          if (selected) {
            this.selection.push(id);
            item.select();
          }
        }
        else {
          throw new TypeError(`Unknown item type "${type}"`);
        }
      }
    });

    this._order();
    
    if (this.options.cluster) {
      this.clusterGenerator.setItems(this.items, { applyOnChangedLevel: false });
      this._clusterItems();
    }

    this.body.emitter.emit('_change', {queue: true});
  }

  /**
   * Handle removed items
   * @param {number[]} ids
   * @protected
   */
  _onRemove(ids) {
    let count = 0;
    const me = this;
    ids.forEach(id => {
      const item = me.items[id];
      if (item) {
        count++;
        me._removeItem(item);
      }
    });

    if (count) {
      // update order
      this._order();
      this.body.emitter.emit('_change', {queue: true});
    }
  }

  /**
   * Update the order of item in all groups
   * @private
   */
  _order() {
    // reorder the items in all groups
    // TODO: optimization: only reorder groups affected by the changed items
    util$3.forEach(this.groups, group => {
      group.order();
    });
  }

  /**
   * Handle updated groups
   * @param {number[]} ids
   * @private
   */
  _onUpdateGroups(ids) {
    this._onAddGroups(ids);
  }

  /**
   * Handle changed groups (added or updated)
   * @param {number[]} ids
   * @private
   */
  _onAddGroups(ids) {
    const me = this;

    ids.forEach(id => {
      const groupData = me.groupsData.get(id);
      let group = me.groups[id];

      if (!group) {
        // check for reserved ids
        if (id == UNGROUPED$2 || id == BACKGROUND$2) {
          throw new Error(`Illegal group id. ${id} is a reserved id.`);
        }

        const groupOptions = Object.create(me.options);
        util$3.extend(groupOptions, {
          height: null
        });

        group = new Group(id, groupData, me);
        me.groups[id] = group;

        // add items with this groupId to the new group
        for (const itemId in me.items) {
          if (me.items.hasOwnProperty(itemId)) {
            const item = me.items[itemId];
            if (item.data.group == id) {
              group.add(item);
            }
          }
        }

        group.order();
        group.show();
      }
      else {
        // update group
        group.setData(groupData);
      }
    });

    this.body.emitter.emit('_change', {queue: true});
  }

  /**
   * Handle removed groups
   * @param {number[]} ids
   * @private
   */
  _onRemoveGroups(ids) {
    ids.forEach(id => {
      const group = this.groups[id];

      if (group) {
        group.dispose();
        delete this.groups[id];
      }
    });

    if (this.options.cluster) {
      this.clusterGenerator.updateData();
      this._clusterItems();
    } 

    this.markDirty({ restackGroups: !!this.options.cluster });
    this.body.emitter.emit('_change', {queue: true});
  }

  /**
   * Reorder the groups if needed
   * @return {boolean} changed
   * @private
   */
  _orderGroups() {
    if (this.groupsData) {
      // reorder the groups
      let groupIds = this.groupsData.getIds({
        order: this.options.groupOrder
      });

      groupIds = this._orderNestedGroups(groupIds);

      const changed = !util$3.equalArray(groupIds, this.groupIds);
      if (changed) {
        // hide all groups, removes them from the DOM
        const groups = this.groups;
        groupIds.forEach(groupId => {
          groups[groupId].hide();
        });

        // show the groups again, attach them to the DOM in correct order
        groupIds.forEach(groupId => {
          groups[groupId].show();
        });

        this.groupIds = groupIds;
      }

      return changed;
    }
    else {
      return false;
    }
  }

  /**
   * Reorder the nested groups
   *
   * @param {Array.<number>} groupIds
   * @returns {Array.<number>}
   * @private
   */
  _orderNestedGroups(groupIds) {
    /**
     * Recursively order nested groups
     *
     * @param {ItemSet} t
     * @param {Array.<number>} groupIds
     * @returns {Array.<number>}
     * @private
     */
    function getOrderedNestedGroups(t, groupIds) {
      let result = [];
      groupIds.forEach(groupId => {
        result.push(groupId);
        const groupData = t.groupsData.get(groupId);
        if (groupData.nestedGroups) {
          const nestedGroupIds = t.groupsData.get({
            filter(nestedGroup) {
              return nestedGroup.nestedInGroup == groupId;
            },
            order: t.options.groupOrder
          }).map(nestedGroup => nestedGroup.id);
          result = result.concat(getOrderedNestedGroups(t, nestedGroupIds));
        }
      });

      return result;
    }

    const topGroupIds = groupIds.filter(groupId => !this.groupsData.get(groupId).nestedInGroup);

    return getOrderedNestedGroups(this, topGroupIds);
  }

  /**
   * Add a new item
   * @param {Item} item
   * @private
   */
  _addItem(item) {
    this.items[item.id] = item;

    // add to group
    const groupId = this.getGroupId(item.data);
    const group = this.groups[groupId];

    if (!group) {
      item.groupShowing = false;
    } else if (group && group.data && group.data.showNested) {
      item.groupShowing = true;
    }

    if (group) group.add(item);
  }

  /**
   * Update an existing item
   * @param {Item} item
   * @param {Object} itemData
   * @private
   */
  _updateItem(item, itemData) {
    // update the items data (will redraw the item when displayed)
    item.setData(itemData);

    const groupId = this.getGroupId(item.data);
    const group = this.groups[groupId];
    if (!group) {
      item.groupShowing = false;
    } else if (group && group.data && group.data.showNested) {
      item.groupShowing = true;
    }
  }

  /**
   * Delete an item from the ItemSet: remove it from the DOM, from the map
   * with items, and from the map with visible items, and from the selection
   * @param {Item} item
   * @private
   */
  _removeItem(item) {
    // remove from DOM
    item.hide();

    // remove from items
    delete this.items[item.id];

    // remove from selection
    const index = this.selection.indexOf(item.id);
    if (index != -1) this.selection.splice(index, 1);

    // remove from group
    item.parent && item.parent.remove(item);

    // remove Tooltip from DOM
    if (this.popup != null) {
      this.popup.hide();
    }
  }

  /**
   * Create an array containing all items being a range (having an end date)
   * @param {Array.<Object>} array
   * @returns {Array}
   * @private
   */
  _constructByEndArray(array) {
    const endArray = [];

    for (let i = 0; i < array.length; i++) {
      if (array[i] instanceof RangeItem) {
        endArray.push(array[i]);
      }
    }
    return endArray;
  }

  /**
   * Register the clicked item on touch, before dragStart is initiated.
   *
   * dragStart is initiated from a mousemove event, AFTER the mouse/touch is
   * already moving. Therefore, the mouse/touch can sometimes be above an other
   * DOM element than the item itself.
   *
   * @param {Event} event
   * @private
   */
  _onTouch(event) {
    // store the touched item, used in _onDragStart
    this.touchParams.item = this.itemFromTarget(event);
    this.touchParams.dragLeftItem = event.target.dragLeftItem || false;
    this.touchParams.dragRightItem = event.target.dragRightItem || false;
    this.touchParams.itemProps = null;
  }

  /**
   * Given an group id, returns the index it has.
   *
   * @param {number} groupId
   * @returns {number} index / groupId
   * @private
   */
  _getGroupIndex(groupId) {
      for (let i = 0; i < this.groupIds.length; i++) {
          if (groupId == this.groupIds[i])
              return i;
      }
  }

  /**
   * Start dragging the selected events
   * @param {Event} event
   * @private
   */
  _onDragStart(event) {
    if (this.touchParams.itemIsDragging) { return; }
    const item = this.touchParams.item || null;
    const me = this;
    let props;

    if (item && (item.selected || this.options.itemsAlwaysDraggable.item)) {

      if (this.options.editable.overrideItems &&
          !this.options.editable.updateTime &&
          !this.options.editable.updateGroup) {
        return;
      }

      // override options.editable
      if ((item.editable != null && !item.editable.updateTime && !item.editable.updateGroup)
          && !this.options.editable.overrideItems) {
        return;
      }

      const dragLeftItem = this.touchParams.dragLeftItem;
      const dragRightItem = this.touchParams.dragRightItem;
      this.touchParams.itemIsDragging = true;
      this.touchParams.selectedItem = item;

      if (dragLeftItem) {
        props = {
          item: dragLeftItem,
          initialX: event.center.x,
          dragLeft:  true,
          data: this._cloneItemData(item.data)
        };

        this.touchParams.itemProps = [props];
      } else if (dragRightItem) {
        props = {
          item: dragRightItem,
          initialX: event.center.x,
          dragRight: true,
          data: this._cloneItemData(item.data)
        };

        this.touchParams.itemProps = [props];
      } else if (this.options.editable.add && (event.srcEvent.ctrlKey || event.srcEvent.metaKey)) {
        // create a new range item when dragging with ctrl key down
        this._onDragStartAddItem(event);
      } else {
        if(this.groupIds.length < 1) {
          // Mitigates a race condition if _onDragStart() is
          // called after markDirty() without redraw() being called between.
          this.redraw();
        }
        
        const baseGroupIndex = this._getGroupIndex(item.data.group);

        const itemsToDrag = (this.options.itemsAlwaysDraggable.item && !item.selected) ? [item.id] : this.getSelection();

        this.touchParams.itemProps = itemsToDrag.map(id => {
          const item = me.items[id];
          const groupIndex = me._getGroupIndex(item.data.group);
          return {
            item,
            initialX: event.center.x,
            groupOffset: baseGroupIndex-groupIndex,
            data: this._cloneItemData(item.data)
          };
        });
      }

      event.stopPropagation();
    } else if (this.options.editable.add && (event.srcEvent.ctrlKey || event.srcEvent.metaKey)) {
      // create a new range item when dragging with ctrl key down
      this._onDragStartAddItem(event);
    }
  }

  /**
   * Start creating a new range item by dragging.
   * @param {Event} event
   * @private
   */
  _onDragStartAddItem(event) {
    const snap = this.options.snap || null;
    const frameRect = this.dom.frame.getBoundingClientRect();

    // plus (if rtl) 10 to compensate for the drag starting as soon as you've moved 10px
    const x = this.options.rtl ? frameRect.right - event.center.x  + 10 : event.center.x - frameRect.left - 10;

    const time = this.body.util.toTime(x);
    const scale = this.body.util.getScale();
    const step = this.body.util.getStep();
    const start = snap ? snap(time, scale, step) : time;
    const end = start;

    const itemData = {
      type: 'range',
      start,
      end,
      content: 'new item'
    };

    const id = dist.v4();
    itemData[this.itemsData.idProp] = id;

    const group = this.groupFromTarget(event);
    if (group) {
      itemData.group = group.groupId;
    }
    const newItem = new RangeItem(itemData, this.conversion, this.options);
    newItem.id = id; // TODO: not so nice setting id afterwards
    newItem.data = this._cloneItemData(itemData);
    this._addItem(newItem);
    this.touchParams.selectedItem = newItem;
    
    const props = {
      item: newItem,
      initialX: event.center.x,
      data: newItem.data
    };

    if (this.options.rtl) {
      props.dragLeft = true;
    } else {
      props.dragRight = true;
    }
    this.touchParams.itemProps = [props];

    event.stopPropagation();
  }

  /**
   * Drag selected items
   * @param {Event} event
   * @private
   */
  _onDrag(event) {
    if (this.popup != null && this.options.showTooltips && !this.popup.hidden) {
      // this.popup.hide();
      const container = this.body.dom.centerContainer;
      const containerRect = container.getBoundingClientRect();
      this.popup.setPosition(
        event.center.x - containerRect.left + container.offsetLeft,
        event.center.y - containerRect.top + container.offsetTop
      );
      this.popup.show(); // redraw
    }
    
    if (this.touchParams.itemProps) {
      event.stopPropagation();

      const me = this;
      const snap = this.options.snap || null;
      const domRootOffsetLeft = this.body.dom.root.offsetLeft;
      const xOffset = this.options.rtl ? domRootOffsetLeft + this.body.domProps.right.width : domRootOffsetLeft + this.body.domProps.left.width;
      const scale = this.body.util.getScale();
      const step = this.body.util.getStep();

      //only calculate the new group for the item that's actually dragged
      const selectedItem = this.touchParams.selectedItem;
      const updateGroupAllowed = ((this.options.editable.overrideItems || selectedItem.editable == null) && this.options.editable.updateGroup) ||
                               (!this.options.editable.overrideItems && selectedItem.editable != null && selectedItem.editable.updateGroup);
      let newGroupBase = null;
      if (updateGroupAllowed && selectedItem) {
        if (selectedItem.data.group != undefined) {
          // drag from one group to another
          const group = me.groupFromTarget(event);
          if (group) {
            //we know the offset for all items, so the new group for all items
            //will be relative to this one.
            newGroupBase = this._getGroupIndex(group.groupId);
          }
        }
      }

      // move
      this.touchParams.itemProps.forEach(props => {
        const current = me.body.util.toTime(event.center.x - xOffset);
        const initial = me.body.util.toTime(props.initialX - xOffset);
        let offset;
        let initialStart;
        let initialEnd;
        let start;
        let end;

        if (this.options.rtl) {
          offset = -(current - initial); // ms
        } else {
          offset = (current - initial); // ms
        }

        let itemData = this._cloneItemData(props.item.data); // clone the data
        if (props.item.editable != null
          && !props.item.editable.updateTime
          && !props.item.editable.updateGroup
          && !me.options.editable.overrideItems) {
          return;
        }

        const updateTimeAllowed = ((this.options.editable.overrideItems || selectedItem.editable == null) && this.options.editable.updateTime) ||
                                 (!this.options.editable.overrideItems && selectedItem.editable != null && selectedItem.editable.updateTime);
        if (updateTimeAllowed) {
          if (props.dragLeft) {
            // drag left side of a range item
            if (this.options.rtl) {
              if (itemData.end != undefined) {
                initialEnd = util$3.convert(props.data.end, 'Date');
                end = new Date(initialEnd.valueOf() + offset);
                // TODO: pass a Moment instead of a Date to snap(). (Breaking change)
                itemData.end = snap ? snap(end, scale, step) : end;
              }
            } else {
              if (itemData.start != undefined) {
                initialStart = util$3.convert(props.data.start, 'Date');
                start = new Date(initialStart.valueOf() + offset);
                // TODO: pass a Moment instead of a Date to snap(). (Breaking change)
                itemData.start = snap ? snap(start, scale, step) : start;
              }
            }
          }
          else if (props.dragRight) {
            // drag right side of a range item
            if (this.options.rtl) {
              if (itemData.start != undefined) {
                initialStart = util$3.convert(props.data.start, 'Date');
                start = new Date(initialStart.valueOf() + offset);
                // TODO: pass a Moment instead of a Date to snap(). (Breaking change)
                itemData.start = snap ? snap(start, scale, step) : start;
              }
            } else {
              if (itemData.end != undefined) {
                initialEnd = util$3.convert(props.data.end, 'Date');
                end = new Date(initialEnd.valueOf() + offset);
                // TODO: pass a Moment instead of a Date to snap(). (Breaking change)
                itemData.end = snap ? snap(end, scale, step) : end;
              }
            }
          }
          else {
            // drag both start and end
            if (itemData.start != undefined) {

              initialStart = util$3.convert(props.data.start, 'Date').valueOf();
              start = new Date(initialStart + offset);

              if (itemData.end != undefined) {
                initialEnd = util$3.convert(props.data.end, 'Date');
                const duration  = initialEnd.valueOf() - initialStart.valueOf();

                // TODO: pass a Moment instead of a Date to snap(). (Breaking change)
                itemData.start = snap ? snap(start, scale, step) : start;
                itemData.end   = new Date(itemData.start.valueOf() + duration);
              }
              else {
                // TODO: pass a Moment instead of a Date to snap(). (Breaking change)
                itemData.start = snap ? snap(start, scale, step) : start;
              }
            }
          }
        }

        if (updateGroupAllowed && (!props.dragLeft && !props.dragRight) && newGroupBase!=null) {
          if (itemData.group != undefined) {
            let newOffset = newGroupBase - props.groupOffset;

            //make sure we stay in bounds
            newOffset = Math.max(0, newOffset);
            newOffset = Math.min(me.groupIds.length-1, newOffset);
            itemData.group = me.groupIds[newOffset];
          }
        }

        // confirm moving the item
        itemData = this._cloneItemData(itemData);  // convert start and end to the correct type
        me.options.onMoving(itemData, itemData => {
          if (itemData) {
            props.item.setData(this._cloneItemData(itemData, 'Date'));
          }
        });
      });
      
      this.body.emitter.emit('_change');
    }
  }

  /**
   * Move an item to another group
   * @param {Item} item
   * @param {string | number} groupId
   * @private
   */
  _moveToGroup(item, groupId) {
    const group = this.groups[groupId];
    if (group && group.groupId != item.data.group) {
      const oldGroup = item.parent;
      oldGroup.remove(item);
      oldGroup.order();
      
      item.data.group = group.groupId;
      
      group.add(item);
      group.order();
    }
  }

  /**
   * End of dragging selected items
   * @param {Event} event
   * @private
   */
  _onDragEnd(event) {
    this.touchParams.itemIsDragging = false;
    if (this.touchParams.itemProps) {
      event.stopPropagation();

      const me = this;
      const itemProps = this.touchParams.itemProps;
      this.touchParams.itemProps = null;

      itemProps.forEach(props => {
        const id = props.item.id;
        const exists = me.itemsData.get(id) != null;

        if (!exists) {
          // add a new item
          me.options.onAdd(props.item.data, itemData => {
            me._removeItem(props.item); // remove temporary item
            if (itemData) {
              me.itemsData.add(itemData);
            }

            // force re-stacking of all items next redraw
            me.body.emitter.emit('_change');
          });
        }
        else {
          // update existing item
          const itemData = this._cloneItemData(props.item.data); // convert start and end to the correct type
          me.options.onMove(itemData, itemData => {
            if (itemData) {
              // apply changes
              itemData[this.itemsData.idProp] = id; // ensure the item contains its id (can be undefined)
              this.itemsData.update(itemData);
            }
            else {
              // restore original values
              props.item.setData(props.data);

              me.body.emitter.emit('_change');
            }
          });
        }
      });
    }
  }

  /**
   * On group click
   * @param {Event} event
   * @private
   */
  _onGroupClick(event) {
    const group = this.groupFromTarget(event);
    setTimeout(() => {
      this.toggleGroupShowNested(group);
    }, 1);
  }
  
  /**
   * Toggle show nested
   * @param {object} group
   * @param {boolean} force
   */
  toggleGroupShowNested(group, force = undefined) {

    if (!group || !group.nestedGroups) return;

    const groupsData = this.groupsData.getDataSet();

    if (force != undefined) {
      group.showNested = !!force;
    } else {
      group.showNested = !group.showNested;
    }

    let nestingGroup = groupsData.get(group.groupId);
    nestingGroup.showNested = group.showNested;

    let fullNestedGroups = group.nestedGroups;
    let nextLevel = fullNestedGroups;
    while (nextLevel.length > 0) {
      let current = nextLevel;
      nextLevel = [];
      for (let i = 0; i < current.length; i++) {
        let node = groupsData.get(current[i]);
        if (node.nestedGroups) {
          nextLevel = nextLevel.concat(node.nestedGroups);
        }
      }
      if (nextLevel.length > 0) {
        fullNestedGroups = fullNestedGroups.concat(nextLevel);
      }
    }
    let nestedGroups = groupsData.get(fullNestedGroups).map(function (nestedGroup) {
        if (nestedGroup.visible == undefined) {
          nestedGroup.visible = true;
        }
        nestedGroup.visible = !!nestingGroup.showNested;
        return nestedGroup;
      });

    groupsData.update(nestedGroups.concat(nestingGroup));

    if (nestingGroup.showNested) {
      util$3.removeClassName(group.dom.label, 'collapsed');
      util$3.addClassName(group.dom.label, 'expanded');
    } else {
      util$3.removeClassName(group.dom.label, 'expanded');
      util$3.addClassName(group.dom.label, 'collapsed');
    }
  }
  
  /**
   * Toggle group drag classname
   * @param {object} group
   */
  toggleGroupDragClassName(group) {
    group.dom.label.classList.toggle('vis-group-is-dragging');
    group.dom.foreground.classList.toggle('vis-group-is-dragging');
  }
  
  /**
   * on drag start
   * @param {Event} event
   * @return {void}   
   * @private
   */
  _onGroupDragStart(event) {
    if (this.groupTouchParams.isDragging) return;

    if (this.options.groupEditable.order) {
      this.groupTouchParams.group = this.groupFromTarget(event);
      
      if (this.groupTouchParams.group) {
        event.stopPropagation();      
        
        this.groupTouchParams.isDragging = true;
        this.toggleGroupDragClassName(this.groupTouchParams.group);
        
        this.groupTouchParams.originalOrder = this.groupsData.getIds({
          order: this.options.groupOrder
        });
      }
    }
  }

  /**
   * on drag
   * @param {Event} event
   * @return {void}
   * @private
   */
  _onGroupDrag(event) {
      if (this.options.groupEditable.order && this.groupTouchParams.group) {
          event.stopPropagation();
          
      const groupsData = this.groupsData.getDataSet();
          // drag from one group to another
          const group = this.groupFromTarget(event);
          
          // try to avoid toggling when groups differ in height
          if (group && group.height != this.groupTouchParams.group.height) {
              const movingUp = (group.top < this.groupTouchParams.group.top);
              const clientY = event.center ? event.center.y : event.clientY;
              const targetGroup = group.dom.foreground.getBoundingClientRect();
              const draggedGroupHeight = this.groupTouchParams.group.height;
              if (movingUp) {
                  // skip swapping the groups when the dragged group is not below clientY afterwards
                  if (targetGroup.top + draggedGroupHeight < clientY) {
                      return;
                  }
              } else {
                  const targetGroupHeight = group.height;
                  // skip swapping the groups when the dragged group is not below clientY afterwards
                  if (targetGroup.top + targetGroupHeight - draggedGroupHeight > clientY) {
                      return;
                  }
              }
          }
          
          if (group && group != this.groupTouchParams.group) {
              const targetGroup = groupsData.get(group.groupId);
              const draggedGroup = groupsData.get(this.groupTouchParams.group.groupId);
              
              // switch groups
              if (draggedGroup && targetGroup) {
                  this.options.groupOrderSwap(draggedGroup, targetGroup, groupsData);
                  groupsData.update(draggedGroup);
                  groupsData.update(targetGroup);
              }
              
              // fetch current order of groups
              const newOrder = groupsData.getIds({
                order: this.options.groupOrder
              });

              
              // in case of changes since _onGroupDragStart
              if (!util$3.equalArray(newOrder, this.groupTouchParams.originalOrder)) {
                  const origOrder = this.groupTouchParams.originalOrder;
                  const draggedId = this.groupTouchParams.group.groupId;
                  const numGroups = Math.min(origOrder.length, newOrder.length);
                  let curPos = 0;
                  let newOffset = 0;
                  let orgOffset = 0;
                  while (curPos < numGroups) {
                      // as long as the groups are where they should be step down along the groups order
                      while ((curPos+newOffset) < numGroups 
                          && (curPos+orgOffset) < numGroups 
                          && newOrder[curPos+newOffset] == origOrder[curPos+orgOffset]) {
                          curPos++;
                      }
                      
                      // all ok
                      if (curPos+newOffset >= numGroups) {
                          break;
                      }
                      
                      // not all ok
                      // if dragged group was move upwards everything below should have an offset
                      if (newOrder[curPos+newOffset] == draggedId) {
                          newOffset = 1;

                      }
                      // if dragged group was move downwards everything above should have an offset
                      else if (origOrder[curPos+orgOffset] == draggedId) {
                          orgOffset = 1;

                      } 
                      // found a group (apart from dragged group) that has the wrong position -> switch with the 
                      // group at the position where other one should be, fix index arrays and continue
                      else {
                          const slippedPosition = newOrder.indexOf(origOrder[curPos+orgOffset]);
                          const switchGroup = groupsData.get(newOrder[curPos+newOffset]);
                          const shouldBeGroup = groupsData.get(origOrder[curPos+orgOffset]);
                          this.options.groupOrderSwap(switchGroup, shouldBeGroup, groupsData);
                          groupsData.update(switchGroup);
                          groupsData.update(shouldBeGroup);
                          
                          const switchGroupId = newOrder[curPos+newOffset];
                          newOrder[curPos+newOffset] = origOrder[curPos+orgOffset];
                          newOrder[slippedPosition] = switchGroupId;
                          
                          curPos++;
                      }
                  }
              }
              
          }
      }
  }

  /**
   * on drag end
   * @param {Event} event
   * @return {void}
   * @private
   */
  _onGroupDragEnd(event) {
    this.groupTouchParams.isDragging = false;

    if (this.options.groupEditable.order && this.groupTouchParams.group) {
      event.stopPropagation();
          
      // update existing group
      const me = this;
      const id = me.groupTouchParams.group.groupId;
      const dataset = me.groupsData.getDataSet();
      const groupData = util$3.extend({}, dataset.get(id)); // clone the data
      me.options.onMoveGroup(groupData, groupData => {
        if (groupData) {
          // apply changes
          groupData[dataset._idProp] = id; // ensure the group contains its id (can be undefined)
          dataset.update(groupData);
        }
        else {

          // fetch current order of groups
          const newOrder = dataset.getIds({
              order: me.options.groupOrder
          });

          // restore original order
          if (!util$3.equalArray(newOrder, me.groupTouchParams.originalOrder)) {
            const origOrder = me.groupTouchParams.originalOrder;
            const numGroups = Math.min(origOrder.length, newOrder.length);
            let curPos = 0;
            while (curPos < numGroups) {
              // as long as the groups are where they should be step down along the groups order
              while (curPos < numGroups && newOrder[curPos] == origOrder[curPos]) {
                curPos++;
              }

              // all ok
              if (curPos >= numGroups) {
                break;
              }

              // found a group that has the wrong position -> switch with the
              // group at the position where other one should be, fix index arrays and continue
              const slippedPosition = newOrder.indexOf(origOrder[curPos]);
              const switchGroup = dataset.get(newOrder[curPos]);
              const shouldBeGroup = dataset.get(origOrder[curPos]);
              me.options.groupOrderSwap(switchGroup, shouldBeGroup, dataset);
              dataset.update(switchGroup);
              dataset.update(shouldBeGroup);

              const switchGroupId = newOrder[curPos];
              newOrder[curPos] = origOrder[curPos];
              newOrder[slippedPosition] = switchGroupId;

              curPos++;
            }
          }
        }
      });

      me.body.emitter.emit('groupDragged', { groupId: id });
      this.toggleGroupDragClassName(this.groupTouchParams.group);
      this.groupTouchParams.group = null;
    }
  }

  /**
   * Handle selecting/deselecting an item when tapping it
   * @param {Event} event
   * @private
   */
  _onSelectItem(event) {
    if (!this.options.selectable) return;

    const ctrlKey  = event.srcEvent && (event.srcEvent.ctrlKey || event.srcEvent.metaKey);
    const shiftKey = event.srcEvent && event.srcEvent.shiftKey;
    if (ctrlKey || shiftKey) {
      this._onMultiSelectItem(event);
      return;
    }

    const oldSelection = this.getSelection();

    const item = this.itemFromTarget(event);
    const selection = item && item.selectable ? [item.id] : [];
    this.setSelection(selection);

    const newSelection = this.getSelection();

    // emit a select event,
    // except when old selection is empty and new selection is still empty
    if (newSelection.length > 0 || oldSelection.length > 0) {
      this.body.emitter.emit('select', {
        items: newSelection,
        event
      });
    }
  }

  /**
   * Handle hovering an item
   * @param {Event} event
   * @private
   */
  _onMouseOver(event) {
    const item = this.itemFromTarget(event);
    if (!item) return;

    // Item we just left
    const related = this.itemFromRelatedTarget(event);
    if (item === related) {
      // We haven't changed item, just element in the item
      return;
    }

    const title = item.getTitle();
    if (this.options.showTooltips && title) {
      if (this.popup == null) {
        this.popup = new Popup$2(this.body.dom.root,
            this.options.tooltip.overflowMethod || 'flip');
      }

      this.popup.setText(title);
      const container = this.body.dom.centerContainer;
      const containerRect = container.getBoundingClientRect();
      this.popup.setPosition(
        event.clientX - containerRect.left + container.offsetLeft,
        event.clientY - containerRect.top + container.offsetTop
      );
      this.setPopupTimer(this.popup);
    } else {
      // Hovering over item without a title, hide popup
      // Needed instead of _just_ in _onMouseOut due to #2572
      this.clearPopupTimer();
      if (this.popup != null) {
        this.popup.hide();
      }
    }

    this.body.emitter.emit('itemover', {
      item: item.id,
      event
    });
  }

  /**
   * on mouse start
   * @param {Event} event
   * @return {void}   
   * @private
   */
  _onMouseOut(event) {
    const item = this.itemFromTarget(event);
    if (!item) return;

    // Item we are going to
    const related = this.itemFromRelatedTarget(event);
    if (item === related) {
      // We aren't changing item, just element in the item
      return;
    }

    this.clearPopupTimer();
    if (this.popup != null) {
      this.popup.hide();
    }

    this.body.emitter.emit('itemout', {
      item: item.id,
      event
    });
  }

  /**
   * on mouse move
   * @param {Event} event
   * @return {void}   
   * @private
   */
  _onMouseMove(event) {
    const item = this.itemFromTarget(event);
    if (!item) return;

    if (this.popupTimer != null) {
      // restart timer
      this.setPopupTimer(this.popup);
    }
    
    if (this.options.showTooltips && this.options.tooltip.followMouse && this.popup && !this.popup.hidden) {
      const container = this.body.dom.centerContainer;
      const containerRect = container.getBoundingClientRect();
      this.popup.setPosition(
        event.clientX - containerRect.left + container.offsetLeft,
        event.clientY - containerRect.top + container.offsetTop
      );
      this.popup.show(); // Redraw
    }
  }

  /**
   * Handle mousewheel
   * @param {Event}  event   The event
   * @private
   */
  _onMouseWheel(event) {
    if (this.touchParams.itemIsDragging) {
      this._onDragEnd(event);
    }
  }

  /**
   * Handle updates of an item on double tap
   * @param {timeline.Item}  item   The item
   * @private
   */
  _onUpdateItem(item) {
    if (!this.options.selectable) return;
    if (!this.options.editable.updateTime && !this.options.editable.updateGroup) return;

    const me = this;
   
    if (item) {
      // execute async handler to update the item (or cancel it)
      const itemData = me.itemsData.get(item.id); // get a clone of the data from the dataset
      this.options.onUpdate(itemData, itemData => {
        if (itemData) {
          me.itemsData.update(itemData);
        }
      });
    }
  }

  /**
   * Handle drop event of data on item
   * Only called when `objectData.target === 'item'.
   * @param {Event} event The event 
   * @private
   */
  _onDropObjectOnItem(event) {
    const item = this.itemFromTarget(event);
    const objectData = JSON.parse(event.dataTransfer.getData("text"));
    this.options.onDropObjectOnItem(objectData, item);
  }

  /**
   * Handle creation of an item on double tap or drop of a drag event
   * @param {Event} event   The event
   * @private
   */
  _onAddItem(event) {
    if (!this.options.selectable) return;
    if (!this.options.editable.add) return;

    const me = this;
    const snap = this.options.snap || null;

    // add item
    const frameRect = this.dom.frame.getBoundingClientRect();
    const x = this.options.rtl ? frameRect.right - event.center.x : event.center.x - frameRect.left;
    const start = this.body.util.toTime(x);
    const scale = this.body.util.getScale();
    const step = this.body.util.getStep();
    let end;

    let newItemData;
    if (event.type == 'drop') {
      newItemData = JSON.parse(event.dataTransfer.getData("text"));
      newItemData.content = newItemData.content ? newItemData.content : 'new item';
      newItemData.start = newItemData.start ? newItemData.start : (snap ? snap(start, scale, step) : start);
      newItemData.type = newItemData.type || 'box';
      newItemData[this.itemsData.idProp] = newItemData.id || dist.v4();

      if (newItemData.type == 'range' && !newItemData.end) {
        end = this.body.util.toTime(x + this.props.width / 5);
        newItemData.end = snap ? snap(end, scale, step) : end;
      }
    } else {
      newItemData = {
        start: snap ? snap(start, scale, step) : start,
        content: 'new item'
      };
      newItemData[this.itemsData.idProp] = dist.v4();

      // when default type is a range, add a default end date to the new item
      if (this.options.type === 'range') {
        end = this.body.util.toTime(x + this.props.width / 5);
        newItemData.end = snap ? snap(end, scale, step) : end;
      }
    }

    const group = this.groupFromTarget(event);
    if (group) {
      newItemData.group = group.groupId;
    }

    // execute async handler to customize (or cancel) adding an item
    newItemData = this._cloneItemData(newItemData);     // convert start and end to the correct type
    this.options.onAdd(newItemData, item => {
      if (item) {
        me.itemsData.add(item);
        if (event.type == 'drop') {
          me.setSelection([item.id]);
        }
        // TODO: need to trigger a redraw?
      }
    });
  }

  /**
   * Handle selecting/deselecting multiple items when holding an item
   * @param {Event} event
   * @private
   */
  _onMultiSelectItem(event) {
    if (!this.options.selectable) return;

    const item = this.itemFromTarget(event);

    if (item) {
      // multi select items (if allowed)

      let selection = this.options.multiselect
        ? this.getSelection() // take current selection
        : [];                 // deselect current selection

      const shiftKey = event.srcEvent && event.srcEvent.shiftKey || false;

      if ((shiftKey || this.options.sequentialSelection) && this.options.multiselect) {
        // select all items between the old selection and the tapped item
        const itemGroup = this.itemsData.get(item.id).group;

        // when filtering get the group of the last selected item
        let lastSelectedGroup = undefined;
        if (this.options.multiselectPerGroup) {
          if (selection.length > 0) {
            lastSelectedGroup = this.itemsData.get(selection[0]).group;
          }
        }

        // determine the selection range
        if (!this.options.multiselectPerGroup || lastSelectedGroup == undefined || lastSelectedGroup == itemGroup) {
          selection.push(item.id);
        }
        const range = ItemSet._getItemRange(this.itemsData.get(selection));
        
        if (!this.options.multiselectPerGroup || lastSelectedGroup == itemGroup) {
          // select all items within the selection range
          selection = [];
          for (const id in this.items) {
            if (this.items.hasOwnProperty(id)) {
              const _item = this.items[id];
              const start = _item.data.start;
              const end = (_item.data.end !== undefined) ? _item.data.end : start;

              if (start >= range.min &&
                  end <= range.max &&
                  (!this.options.multiselectPerGroup || lastSelectedGroup == this.itemsData.get(_item.id).group) &&
                  !(_item instanceof BackgroundItem)) {
                selection.push(_item.id); // do not use id but item.id, id itself is stringified
              }
            }
          }
        }
      }
      else {
        // add/remove this item from the current selection
        const index = selection.indexOf(item.id);
        if (index == -1) {
          // item is not yet selected -> select it
          selection.push(item.id);
        }
        else {
          // item is already selected -> deselect it
          selection.splice(index, 1);
        }
      }

      const filteredSelection = selection.filter(item => this.getItemById(item).selectable);

      this.setSelection(filteredSelection);

      this.body.emitter.emit('select', {
        items: this.getSelection(),
        event
      });
    }
  }

  /**
   * Calculate the time range of a list of items
   * @param {Array.<Object>} itemsData
   * @return {{min: Date, max: Date}} Returns the range of the provided items
   * @private
   */
  static _getItemRange(itemsData) {
    let max = null;
    let min = null;

    itemsData.forEach(data => {
      if (min == null || data.start < min) {
        min = data.start;
      }

      if (data.end != undefined) {
        if (max == null || data.end > max) {
          max = data.end;
        }
      }
      else {
        if (max == null || data.start > max) {
          max = data.start;
        }
      }
    });

    return {
      min,
      max
    }
  }

  /**
   * Find an item from an element:
   * searches for the attribute 'vis-item' in the element's tree
   * @param {HTMLElement} element
   * @return {Item | null} item
   */
  itemFromElement(element) {
    let cur = element;
    while (cur) {
      if (cur.hasOwnProperty('vis-item')) {
        return cur['vis-item'];
      }
      cur = cur.parentNode;
    }

    return null;
  }

  /**
   * Find an item from an event target:
   * searches for the attribute 'vis-item' in the event target's element tree
   * @param {Event} event
   * @return {Item | null} item
   */
  itemFromTarget(event) {
    return this.itemFromElement(event.target);
  }

  /**
   * Find an item from an event's related target:
   * searches for the attribute 'vis-item' in the related target's element tree
   * @param {Event} event
   * @return {Item | null} item
   */
  itemFromRelatedTarget(event) {
    return this.itemFromElement(event.relatedTarget);
  }

  /**
   * Find the Group from an event target:
   * searches for the attribute 'vis-group' in the event target's element tree
   * @param {Event} event
   * @return {Group | null} group
   */
  groupFromTarget(event) {
    const clientY = event.center ? event.center.y : event.clientY;
    let groupIds = this.groupIds;
    
    if (groupIds.length <= 0 && this.groupsData) {
      groupIds = this.groupsData.getIds({
        order: this.options.groupOrder
      });
    }
    
    for (let i = 0; i < groupIds.length; i++) {
      const groupId = groupIds[i];
      const group = this.groups[groupId];
      const foreground = group.dom.foreground;
      const foregroundRect = foreground.getBoundingClientRect();
      if (clientY >= foregroundRect.top && clientY < foregroundRect.top + foreground.offsetHeight) {
        return group;
      }

      if (this.options.orientation.item === 'top') {
        if (i === this.groupIds.length - 1 && clientY > foregroundRect.top) {
          return group;
        }
      }
      else {
        if (i === 0 && clientY < foregroundRect.top + foreground.offset) {
          return group;
        }
      }
    }

    return null;
  }

  /**
   * Find the ItemSet from an event target:
   * searches for the attribute 'vis-itemset' in the event target's element tree
   * @param {Event} event
   * @return {ItemSet | null} item
   */
  static itemSetFromTarget(event) {
    let target = event.target;
    while (target) {
      if (target.hasOwnProperty('vis-itemset')) {
        return target['vis-itemset'];
      }
      target = target.parentNode;
    }

    return null;
  }

  /**
   * Clone the data of an item, and "normalize" it: convert the start and end date
   * to the type (Date, Moment, ...) configured in the DataSet. If not configured,
   * start and end are converted to Date.
   * @param {Object} itemData, typically `item.data`
   * @param {string} [type]  Optional Date type. If not provided, the type from the DataSet is taken
   * @return {Object} The cloned object
   * @private
   */
  _cloneItemData(itemData, type) {
    const clone = util$3.extend({}, itemData);

    if (!type) {
      // convert start and end date to the type (Date, Moment, ...) configured in the DataSet
      type = this.itemsData.type;
    }

    if (clone.start != undefined) {
      clone.start = util$3.convert(clone.start, type && type.start || 'Date');
    }
    if (clone.end != undefined) {
      clone.end = util$3.convert(clone.end , type && type.end || 'Date');
    }

    return clone;
  }

  /**
   * cluster items
   * @return {void}   
   * @private
   */
  _clusterItems() {
    if (!this.options.cluster) {
      return;
    }

    const { scale } = this.body.range.conversion(this.body.domProps.center.width);
    const clusters = this.clusterGenerator.getClusters(this.clusters, scale, this.options.cluster);

    if (this.clusters != clusters) {
      this._detachAllClusters();

      if (clusters) {
        for (let cluster of clusters) {
          cluster.attach();
        }
        this.clusters = clusters;
      }

      this._updateClusters(clusters);
    }
  }

  /**
   * detach all cluster items
   * @private
   */
  _detachAllClusters() {
    if (this.options.cluster) {
      if (this.clusters && this.clusters.length) {
        for (let cluster of this.clusters) {
          cluster.detach();
        }
      }
    }
  }

  /**
   * update clusters
   * @param {array} clusters
   * @private
   */
  _updateClusters(clusters) {
    if (this.clusters && this.clusters.length) {
      const newClustersIds = new Set(clusters.map(cluster => cluster.id));
      const clustersToUnselect = this.clusters.filter(cluster => !newClustersIds.has(cluster.id));
      let selectionChanged = false;
      for (let cluster of clustersToUnselect) {
        const selectedIdx = this.selection.indexOf(cluster.id);
        if (selectedIdx !== -1) {
          cluster.unselect();
          this.selection.splice(selectedIdx, 1);
          selectionChanged = true;
        }
      }

      if (selectionChanged) {
        const newSelection = this.getSelection();
        this.body.emitter.emit('select', {
          items: newSelection,
          event: event
        });
      }
    }

    this.clusters = clusters || [];
  }
}

// available item types will be registered here
ItemSet.types = {
  background: BackgroundItem,
  box: BoxItem,
  range: RangeItem,
  point: PointItem
};

/**
 * Handle added items
 * @param {number[]} ids
 * @protected
 */
ItemSet.prototype._onAdd = ItemSet.prototype._onUpdate;

let errorFound$1 = false;
let allOptions$1;
let printStyle = 'background: #FFeeee; color: #dd0000';
/**
 *  Used to validate options.
 */
class Validator$2 {
  /**
   * @ignore
   */
  constructor() {
  }

  /**
   * Main function to be called
   * @param {Object} options
   * @param {Object} referenceOptions
   * @param {Object} subObject
   * @returns {boolean}
   * @static
   */
  static validate(options, referenceOptions, subObject) {
    errorFound$1 = false;
    allOptions$1 = referenceOptions;
    let usedOptions = referenceOptions;
    if (subObject !== undefined) {
      usedOptions = referenceOptions[subObject];
    }
    Validator$2.parse(options, usedOptions, []);
    return errorFound$1;
  }


  /**
   * Will traverse an object recursively and check every value
   * @param {Object} options
   * @param {Object} referenceOptions
   * @param {array} path    | where to look for the actual option
   * @static
   */
  static parse(options, referenceOptions, path) {
    for (let option in options) {
      if (options.hasOwnProperty(option)) {
        Validator$2.check(option, options, referenceOptions, path);
      }
    }
  }


  /**
   * Check every value. If the value is an object, call the parse function on that object.
   * @param {string} option
   * @param {Object} options
   * @param {Object} referenceOptions
   * @param {array} path    | where to look for the actual option
   * @static
   */
  static check(option, options, referenceOptions, path) {
    if (referenceOptions[option] === undefined && referenceOptions.__any__ === undefined) {
      Validator$2.getSuggestion(option, referenceOptions, path);
      return;
    }

    let referenceOption = option;
    let is_object = true;

    if (referenceOptions[option] === undefined && referenceOptions.__any__ !== undefined) {
      // NOTE: This only triggers if the __any__ is in the top level of the options object.
      //       THAT'S A REALLY BAD PLACE TO ALLOW IT!!!!
      // TODO: Examine if needed, remove if possible

      // __any__ is a wildcard. Any value is accepted and will be further analysed by reference.
      referenceOption = '__any__';

      // if the any-subgroup is not a predefined object in the configurator,
      // we do not look deeper into the object.
      is_object = (Validator$2.getType(options[option]) === 'object');
    }

    let refOptionObj = referenceOptions[referenceOption];
    if (is_object && refOptionObj.__type__ !== undefined) {
      refOptionObj = refOptionObj.__type__;
    }

    Validator$2.checkFields(option, options, referenceOptions, referenceOption, refOptionObj, path);
  }

  /**
   *
   * @param {string}  option           | the option property
   * @param {Object}  options          | The supplied options object
   * @param {Object}  referenceOptions | The reference options containing all options and their allowed formats
   * @param {string}  referenceOption  | Usually this is the same as option, except when handling an __any__ tag.
   * @param {string}  refOptionObj     | This is the type object from the reference options
   * @param {Array}   path             | where in the object is the option
   * @static
   */
  static checkFields(option, options, referenceOptions, referenceOption, refOptionObj, path) {
    let log = function(message) {
      console.log('%c' + message + Validator$2.printLocation(path, option), printStyle);
    };

    let optionType = Validator$2.getType(options[option]);
    let refOptionType = refOptionObj[optionType];

    if (refOptionType !== undefined) {
      // if the type is correct, we check if it is supposed to be one of a few select values
      if (Validator$2.getType(refOptionType) === 'array' && refOptionType.indexOf(options[option]) === -1) {
        log('Invalid option detected in "' + option + '".' +
          ' Allowed values are:' + Validator$2.print(refOptionType) +
          ' not "' + options[option] + '". ');
        errorFound$1 = true;
      }
      else if (optionType === 'object' && referenceOption !== "__any__") {
        path = util$3.copyAndExtendArray(path, option);
        Validator$2.parse(options[option], referenceOptions[referenceOption], path);
      }
    }
    else if (refOptionObj['any'] === undefined) {
      // type of the field is incorrect and the field cannot be any
      log('Invalid type received for "' + option +
        '". Expected: ' + Validator$2.print(Object.keys(refOptionObj)) +
        '. Received ['  + optionType + '] "' + options[option] + '"');
      errorFound$1 = true;
    }
  }

  /**
   *
   * @param {Object|boolean|number|string|Array.<number>|Date|Node|Moment|undefined|null} object
   * @returns {string}
   * @static
   */
  static getType(object) {
    var type = typeof object;

    if (type === 'object') {
      if (object === null) {
        return 'null';
      }
      if (object instanceof Boolean) {
        return 'boolean';
      }
      if (object instanceof Number) {
        return 'number';
      }
      if (object instanceof String) {
        return 'string';
      }
      if (Array.isArray(object)) {
        return 'array';
      }
      if (object instanceof Date) {
        return 'date';
      }
      if (object.nodeType !== undefined) {
        return 'dom';
      }
      if (object._isAMomentObject === true) {
        return 'moment';
      }
      return 'object';
    }
    else if (type === 'number') {
      return 'number';
    }
    else if (type === 'boolean') {
      return 'boolean';
    }
    else if (type === 'string') {
      return 'string';
    }
    else if (type === undefined) {
      return 'undefined';
    }
    return type;
  }

  /**
   * @param {string} option
   * @param {Object} options
   * @param {Array.<string>} path
   * @static
   */
  static getSuggestion(option, options, path) {
    let localSearch = Validator$2.findInOptions(option,options,path,false);
    let globalSearch = Validator$2.findInOptions(option,allOptions$1,[],true);

    let localSearchThreshold = 8;
    let globalSearchThreshold = 4;

    let msg;
    if (localSearch.indexMatch !== undefined) {
      msg = ' in ' + Validator$2.printLocation(localSearch.path, option,'') +
        'Perhaps it was incomplete? Did you mean: "' + localSearch.indexMatch + '"?\n\n';
    }
    else if (globalSearch.distance <= globalSearchThreshold && localSearch.distance > globalSearch.distance) {
      msg = ' in ' + Validator$2.printLocation(localSearch.path, option,'') +
        'Perhaps it was misplaced? Matching option found at: ' +
        Validator$2.printLocation(globalSearch.path, globalSearch.closestMatch,'');
    }
    else if (localSearch.distance <= localSearchThreshold) {
      msg = '. Did you mean "' + localSearch.closestMatch + '"?' +
        Validator$2.printLocation(localSearch.path, option);
    }
    else {
      msg = '. Did you mean one of these: ' + Validator$2.print(Object.keys(options)) +
      Validator$2.printLocation(path, option);
    }

    console.log('%cUnknown option detected: "' + option + '"' + msg, printStyle);
    errorFound$1 = true;
  }

  /**
   * traverse the options in search for a match.
   * @param {string} option
   * @param {Object} options
   * @param {Array} path    | where to look for the actual option
   * @param {boolean} [recursive=false]
   * @returns {{closestMatch: string, path: Array, distance: number}}
   * @static
   */
  static findInOptions(option, options, path, recursive = false) {
    let min = 1e9;
    let closestMatch = '';
    let closestMatchPath = [];
    let lowerCaseOption = option.toLowerCase();
    let indexMatch = undefined;
    for (let op in options) {  // eslint-disable-line guard-for-in
      let distance;
      if (options[op].__type__ !== undefined && recursive === true) {
        let result = Validator$2.findInOptions(option, options[op], util$3.copyAndExtendArray(path,op));
        if (min > result.distance) {
          closestMatch = result.closestMatch;
          closestMatchPath = result.path;
          min = result.distance;
          indexMatch = result.indexMatch;
        }
      }
      else {
        if (op.toLowerCase().indexOf(lowerCaseOption) !== -1) {
          indexMatch = op;
        }
        distance = Validator$2.levenshteinDistance(option, op);
        if (min > distance) {
          closestMatch = op;
          closestMatchPath = util$3.copyArray(path);
          min = distance;
        }
      }
    }
    return {closestMatch:closestMatch, path:closestMatchPath, distance:min, indexMatch: indexMatch};
  }

  /**
   * @param {Array.<string>} path
   * @param {Object} option
   * @param {string} prefix
   * @returns {String}
   * @static
   */
  static printLocation(path, option, prefix = 'Problem value found at: \n') {
    let str = '\n\n' + prefix + 'options = {\n';
    for (let i = 0; i < path.length; i++) {
      for (let j = 0; j < i + 1; j++) {
        str += '  ';
      }
      str += path[i] + ': {\n';
    }
    for (let j = 0; j < path.length + 1; j++) {
      str += '  ';
    }
    str += option + '\n';
    for (let i = 0; i < path.length + 1; i++) {
      for (let j = 0; j < path.length - i; j++) {
        str += '  ';
      }
      str += '}\n';
    }
    return str + '\n\n';
  }

  /**
   * @param {Object} options
   * @returns {String}
   * @static
   */
  static print(options) {
    return JSON.stringify(options).replace(/(\")|(\[)|(\])|(,"__type__")/g, "").replace(/(\,)/g, ', ')
  }


  /**
   *  Compute the edit distance between the two given strings
   * http://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Levenshtein_distance#JavaScript
   *
   * Copyright (c) 2011 Andrei Mackenzie
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   * @param {string} a
   * @param {string} b
   * @returns {Array.<Array.<number>>}}
   * @static
   */
  static levenshteinDistance(a, b) {
    if (a.length === 0) return b.length;
    if (b.length === 0) return a.length;

    var matrix = [];

    // increment along the first column of each row
    var i;
    for (i = 0; i <= b.length; i++) {
      matrix[i] = [i];
    }

    // increment each column in the first row
    var j;
    for (j = 0; j <= a.length; j++) {
      matrix[0][j] = j;
    }

    // Fill in the rest of the matrix
    for (i = 1; i <= b.length; i++) {
      for (j = 1; j <= a.length; j++) {
        if (b.charAt(i - 1) == a.charAt(j - 1)) {
          matrix[i][j] = matrix[i - 1][j - 1];
        } else {
          matrix[i][j] = Math.min(matrix[i - 1][j - 1] + 1, // substitution
            Math.min(matrix[i][j - 1] + 1, // insertion
              matrix[i - 1][j] + 1)); // deletion
        }
      }
    }

    return matrix[b.length][a.length];
  }
}

/**
 * This object contains all possible options. It will check if the types are correct, if required if the option is one
 * of the allowed values.
 *
 * __any__ means that the name of the property does not matter.
 * __type__ is a required field for all objects and contains the allowed types of all objects
 */
let string = 'string';
let bool = 'boolean';
let number = 'number';
let array = 'array';
let date = 'date';
let object = 'object'; // should only be in a __type__ property
let dom = 'dom';
let moment$1$1 = 'moment';
let any = 'any';

let allOptions$1$1 = {
  configure: {
    enabled: { 'boolean': bool},
    filter: { 'boolean': bool,'function': 'function'},
    container: {dom},
    __type__: {object, 'boolean': bool,'function': 'function'}
  },

  //globals :
  align: {string},
  alignCurrentTime: {string, 'undefined': 'undefined'},
  rtl: { 'boolean': bool, 'undefined': 'undefined'},
  rollingMode: {
    follow: { 'boolean': bool },
    offset: {number,'undefined': 'undefined'},
    __type__: {object}
  },
  onTimeout: {
    timeoutMs: {number},
    callback: {'function': 'function'},
    __type__: {object}
  },
  verticalScroll: { 'boolean': bool, 'undefined': 'undefined'},
  horizontalScroll: { 'boolean': bool, 'undefined': 'undefined'},
  autoResize: { 'boolean': bool},
  throttleRedraw: {number}, // TODO: DEPRICATED see https://github.com/almende/vis/issues/2511
  clickToUse: { 'boolean': bool},
  dataAttributes: {string, array},
  editable: {
    add: { 'boolean': bool, 'undefined': 'undefined'},
    remove: { 'boolean': bool, 'undefined': 'undefined'},
    updateGroup: { 'boolean': bool, 'undefined': 'undefined'},
    updateTime: { 'boolean': bool, 'undefined': 'undefined'},
    overrideItems: { 'boolean': bool, 'undefined': 'undefined'},
    __type__: { 'boolean': bool, object}
  },
  end: {number, date, string, moment: moment$1$1},
  format: {
    minorLabels: {
      millisecond: {string,'undefined': 'undefined'},
      second: {string,'undefined': 'undefined'},
      minute: {string,'undefined': 'undefined'},
      hour: {string,'undefined': 'undefined'},
      weekday: {string,'undefined': 'undefined'},
      day: {string,'undefined': 'undefined'},
      week: {string,'undefined': 'undefined'},
      month: {string,'undefined': 'undefined'},
      year: {string,'undefined': 'undefined'},
      __type__: {object, 'function': 'function'}
    },
    majorLabels: {
      millisecond: {string,'undefined': 'undefined'},
      second: {string,'undefined': 'undefined'},
      minute: {string,'undefined': 'undefined'},
      hour: {string,'undefined': 'undefined'},
      weekday: {string,'undefined': 'undefined'},
      day: {string,'undefined': 'undefined'},
      week: {string,'undefined': 'undefined'},
      month: {string,'undefined': 'undefined'},
      year: {string,'undefined': 'undefined'},
      __type__: {object, 'function': 'function'}
    },
    __type__: {object}
  },
  moment: {'function': 'function'},
  groupHeightMode: {string},
  groupOrder: {string, 'function': 'function'},
  groupEditable: {
    add: { 'boolean': bool, 'undefined': 'undefined'},
    remove: { 'boolean': bool, 'undefined': 'undefined'},
    order: { 'boolean': bool, 'undefined': 'undefined'},
    __type__: { 'boolean': bool, object}
  },
  groupOrderSwap: {'function': 'function'},
  height: {string, number},
  hiddenDates: {
    start: {date, number, string, moment: moment$1$1},
    end: {date, number, string, moment: moment$1$1},
    repeat: {string},
    __type__: {object, array}
  },
  itemsAlwaysDraggable: {
    item: { 'boolean': bool, 'undefined': 'undefined'},
    range: { 'boolean': bool, 'undefined': 'undefined'},
    __type__: { 'boolean': bool, object}
  },
  limitSize: {'boolean': bool},
  locale:{string},
  locales:{
    __any__: {any},
    __type__: {object}
  },
  longSelectPressTime: {number},
  margin: {
    axis: {number},
    item: {
      horizontal: {number,'undefined': 'undefined'},
      vertical: {number,'undefined': 'undefined'},
      __type__: {object,number}
    },
    __type__: {object,number}
  },
  max: {date, number, string, moment: moment$1$1},
  maxHeight: {number, string},
  maxMinorChars: {number},
  min: {date, number, string, moment: moment$1$1},
  minHeight: {number, string},
  moveable: { 'boolean': bool},
  multiselect: { 'boolean': bool},
  multiselectPerGroup: { 'boolean': bool},
  onAdd: {'function': 'function'},
  onDropObjectOnItem: {'function': 'function'},
  onUpdate: {'function': 'function'},
  onMove: {'function': 'function'},
  onMoving: {'function': 'function'},
  onRemove: {'function': 'function'},
  onAddGroup: {'function': 'function'},
  onMoveGroup: {'function': 'function'},
  onRemoveGroup: {'function': 'function'},
  onInitialDrawComplete: {'function': 'function'},
  order: {'function': 'function'},
  orientation: {
    axis: {string,'undefined': 'undefined'},
    item: {string,'undefined': 'undefined'},
    __type__: {string, object}
  },
  selectable: { 'boolean': bool},
  sequentialSelection: { 'boolean': bool },
  showCurrentTime: { 'boolean': bool},
  showMajorLabels: { 'boolean': bool},
  showMinorLabels: { 'boolean': bool},
  showWeekScale: { 'boolean': bool},
  stack: { 'boolean': bool},
  stackSubgroups: { 'boolean': bool},
  cluster: { 
    maxItems: {'number': number, 'undefined': 'undefined'},
    titleTemplate: {'string': string, 'undefined': 'undefined'},
    clusterCriteria: { 'function': 'function', 'undefined': 'undefined'},
    showStipes: {'boolean': bool, 'undefined': 'undefined'},
    fitOnDoubleClick: {'boolean': bool, 'undefined': 'undefined'},
    __type__: {'boolean': bool, object}
  },
  snap: {'function': 'function', 'null': 'null'},
  start: {date, number, string, moment: moment$1$1},
  template: {'function': 'function'},
  loadingScreenTemplate: {'function': 'function'},
  groupTemplate: {'function': 'function'},
  visibleFrameTemplate: {string, 'function': 'function'},
  showTooltips: { 'boolean': bool},
  tooltip: {
    followMouse: { 'boolean': bool },
    overflowMethod: { 'string': ['cap', 'flip', 'none'] },
    delay: {number},
    template: {'function': 'function'},
    __type__: {object}
  },
  tooltipOnItemUpdateTime: {
    template: {'function': 'function'},
    __type__: { 'boolean': bool, object}
  },
  timeAxis: {
    scale: {string,'undefined': 'undefined'},
    step: {number,'undefined': 'undefined'},
    __type__: {object}
  },
  type: {string},
  width: {string, number},
  preferZoom: { 'boolean': bool},
  zoomable: { 'boolean': bool},
  zoomKey: {string: ['ctrlKey', 'altKey', 'shiftKey', 'metaKey', '']},
  zoomFriction: {number},
  zoomMax: {number},
  zoomMin: {number},

  __type__: {object}
};

let configureOptions = {
  global: {
    align:  ['center', 'left', 'right'],
    alignCurrentTime: ['none', 'year', 'month', 'quarter', 'week', 'isoWeek', 'day', 'date', 'hour', 'minute', 'second'],
    direction:  false,
    autoResize: true,
    clickToUse: false,
    // dataAttributes: ['all'], // FIXME: can be 'all' or string[]
      editable: {
      add: false,
      remove: false,
      updateGroup: false,
      updateTime: false
    },
    end: '',
    format: {
      minorLabels: {
        millisecond:'SSS',
        second:     's',
        minute:     'HH:mm',
        hour:       'HH:mm',
        weekday:    'ddd D',
        day:        'D',
        week:       'w',
        month:      'MMM',
        year:       'YYYY'
      },
      majorLabels: {
        millisecond:'HH:mm:ss',
        second:     'D MMMM HH:mm',
        minute:     'ddd D MMMM',
        hour:       'ddd D MMMM',
        weekday:    'MMMM YYYY',
        day:        'MMMM YYYY',
        week:       'MMMM YYYY',
        month:      'YYYY',
        year:       ''
      }
    },
    groupHeightMode: ['auto', 'fixed', 'fitItems'],
    //groupOrder: {string, 'function': 'function'},
    groupsDraggable: false,
    height: '',
    //hiddenDates: {object, array},
    locale: '',
    longSelectPressTime: 251,
    margin: {
      axis: [20, 0, 100, 1],
      item: {
        horizontal: [10, 0, 100, 1],
        vertical: [10, 0, 100, 1]
      }
    },
    max: '',
    maxHeight: '',
    maxMinorChars: [7, 0, 20, 1],
    min: '',
    minHeight: '',
    moveable: false,
    multiselect: false,
    multiselectPerGroup: false,
    //onAdd: {'function': 'function'},
    //onUpdate: {'function': 'function'},
    //onMove: {'function': 'function'},
    //onMoving: {'function': 'function'},
    //onRename: {'function': 'function'},
    //order: {'function': 'function'},
    orientation: {
      axis: ['both', 'bottom', 'top'],
      item: ['bottom', 'top']
    },
    preferZoom: false,
    selectable: true,
    showCurrentTime: false,
    showMajorLabels: true,
    showMinorLabels: true,
    stack: true,
    stackSubgroups: true,
    cluster: false,
    //snap: {'function': 'function', nada},
    start: '',
    //template: {'function': 'function'},
    //timeAxis: {
    //  scale: ['millisecond', 'second', 'minute', 'hour', 'weekday', 'day', 'week', 'month', 'year'],
    //  step: [1, 1, 10, 1]
    //},
    showTooltips: true,
    tooltip: {
      followMouse: false,
      overflowMethod: 'flip',
      delay: [500, 0, 99999, 100],
    },
    tooltipOnItemUpdateTime: false,
    type: ['box', 'point', 'range', 'background'],
    width: '100%',
    zoomable: true,
    zoomKey: ['ctrlKey', 'altKey', 'shiftKey', 'metaKey', ''],
    zoomMax: [315360000000000, 10, 315360000000000, 1],
    zoomMin: [10, 10, 315360000000000, 1]
  }
};

var htmlColors$1 = {black: '#000000', navy: '#000080', darkblue: '#00008B', mediumblue: '#0000CD', blue: '#0000FF', darkgreen: '#006400', green: '#008000', teal: '#008080', darkcyan: '#008B8B', deepskyblue: '#00BFFF', darkturquoise: '#00CED1', mediumspringgreen: '#00FA9A', lime: '#00FF00', springgreen: '#00FF7F', aqua: '#00FFFF', cyan: '#00FFFF', midnightblue: '#191970', dodgerblue: '#1E90FF', lightseagreen: '#20B2AA', forestgreen: '#228B22', seagreen: '#2E8B57', darkslategray: '#2F4F4F', limegreen: '#32CD32', mediumseagreen: '#3CB371', turquoise: '#40E0D0', royalblue: '#4169E1', steelblue: '#4682B4', darkslateblue: '#483D8B', mediumturquoise: '#48D1CC', indigo: '#4B0082', darkolivegreen: '#556B2F', cadetblue: '#5F9EA0', cornflowerblue: '#6495ED', mediumaquamarine: '#66CDAA', dimgray: '#696969', slateblue: '#6A5ACD', olivedrab: '#6B8E23', slategray: '#708090', lightslategray: '#778899', mediumslateblue: '#7B68EE', lawngreen: '#7CFC00', chartreuse: '#7FFF00', aquamarine: '#7FFFD4', maroon: '#800000', purple: '#800080', olive: '#808000', gray: '#808080', skyblue: '#87CEEB', lightskyblue: '#87CEFA', blueviolet: '#8A2BE2', darkred: '#8B0000', darkmagenta: '#8B008B', saddlebrown: '#8B4513', darkseagreen: '#8FBC8F', lightgreen: '#90EE90', mediumpurple: '#9370D8', darkviolet: '#9400D3', palegreen: '#98FB98', darkorchid: '#9932CC', yellowgreen: '#9ACD32', sienna: '#A0522D', brown: '#A52A2A', darkgray: '#A9A9A9', lightblue: '#ADD8E6', greenyellow: '#ADFF2F', paleturquoise: '#AFEEEE', lightsteelblue: '#B0C4DE', powderblue: '#B0E0E6', firebrick: '#B22222', darkgoldenrod: '#B8860B', mediumorchid: '#BA55D3', rosybrown: '#BC8F8F', darkkhaki: '#BDB76B', silver: '#C0C0C0', mediumvioletred: '#C71585', indianred: '#CD5C5C', peru: '#CD853F', chocolate: '#D2691E', tan: '#D2B48C', lightgrey: '#D3D3D3', palevioletred: '#D87093', thistle: '#D8BFD8', orchid: '#DA70D6', goldenrod: '#DAA520', crimson: '#DC143C', gainsboro: '#DCDCDC', plum: '#DDA0DD', burlywood: '#DEB887', lightcyan: '#E0FFFF', lavender: '#E6E6FA', darksalmon: '#E9967A', violet: '#EE82EE', palegoldenrod: '#EEE8AA', lightcoral: '#F08080', khaki: '#F0E68C', aliceblue: '#F0F8FF', honeydew: '#F0FFF0', azure: '#F0FFFF', sandybrown: '#F4A460', wheat: '#F5DEB3', beige: '#F5F5DC', whitesmoke: '#F5F5F5', mintcream: '#F5FFFA', ghostwhite: '#F8F8FF', salmon: '#FA8072', antiquewhite: '#FAEBD7', linen: '#FAF0E6', lightgoldenrodyellow: '#FAFAD2', oldlace: '#FDF5E6', red: '#FF0000', fuchsia: '#FF00FF', magenta: '#FF00FF', deeppink: '#FF1493', orangered: '#FF4500', tomato: '#FF6347', hotpink: '#FF69B4', coral: '#FF7F50', darkorange: '#FF8C00', lightsalmon: '#FFA07A', orange: '#FFA500', lightpink: '#FFB6C1', pink: '#FFC0CB', gold: '#FFD700', peachpuff: '#FFDAB9', navajowhite: '#FFDEAD', moccasin: '#FFE4B5', bisque: '#FFE4C4', mistyrose: '#FFE4E1', blanchedalmond: '#FFEBCD', papayawhip: '#FFEFD5', lavenderblush: '#FFF0F5', seashell: '#FFF5EE', cornsilk: '#FFF8DC', lemonchiffon: '#FFFACD', floralwhite: '#FFFAF0', snow: '#FFFAFA', yellow: '#FFFF00', lightyellow: '#FFFFE0', ivory: '#FFFFF0', white: '#FFFFFF'};

/**
 * @param {number} [pixelRatio=1]
 */
class ColorPicker$2 {
  /**
   * @param {number} [pixelRatio=1]
   */
  constructor(pixelRatio = 1) {
    this.pixelRatio = pixelRatio;
    this.generated = false;
    this.centerCoordinates = {x:289/2, y:289/2};
    this.r = 289 * 0.49;
    this.color = {r:255,g:255,b:255,a:1.0};
    this.hueCircle = undefined;
    this.initialColor = {r:255,g:255,b:255,a:1.0};
    this.previousColor= undefined;
    this.applied = false;

    // bound by
    this.updateCallback = () => {};
    this.closeCallback = () => {};

    // create all DOM elements
    this._create();
  }


  /**
   * this inserts the colorPicker into a div from the DOM
   * @param {Element} container
   */
  insertTo(container) {
    if (this.hammer !== undefined) {
      this.hammer.destroy();
      this.hammer = undefined;
    }
    this.container = container;
    this.container.appendChild(this.frame);
    this._bindHammer();

    this._setSize();
  }

  /**
   * the callback is executed on apply and save. Bind it to the application
   * @param {function} callback
   */
  setUpdateCallback(callback) {
    if (typeof callback === 'function') {
      this.updateCallback = callback;
    }
    else {
      throw new Error("Function attempted to set as colorPicker update callback is not a function.");
    }
  }

  /**
   * the callback is executed on apply and save. Bind it to the application
   * @param {function} callback
   */
  setCloseCallback(callback) {
    if (typeof callback === 'function') {
      this.closeCallback = callback;
    }
    else {
      throw new Error("Function attempted to set as colorPicker closing callback is not a function.");
    }
  }

  /**
   *
   * @param {string} color
   * @returns {String}
   * @private
   */
  _isColorString(color) {
    if (typeof color === 'string') {
      return htmlColors$1[color];
    }
  }


  /**
   * Set the color of the colorPicker
   * Supported formats:
   * 'red'                   --> HTML color string
   * '#ffffff'               --> hex string
   * 'rgb(255,255,255)'      --> rgb string
   * 'rgba(255,255,255,1.0)' --> rgba string
   * {r:255,g:255,b:255}     --> rgb object
   * {r:255,g:255,b:255,a:1.0} --> rgba object
   * @param {string|Object} color
   * @param {boolean} [setInitial=true]
   */
  setColor(color, setInitial = true) {
    if (color === 'none') {
      return;
    }

    let rgba;

    // if a html color shorthand is used, convert to hex
    var htmlColor = this._isColorString(color);
    if (htmlColor !== undefined) {
      color = htmlColor;
    }

    // check format
    if (util$3.isString(color) === true) {
      if (util$3.isValidRGB(color) === true) {
        let rgbaArray = color.substr(4).substr(0, color.length - 5).split(',');
        rgba = {r:rgbaArray[0], g:rgbaArray[1], b:rgbaArray[2], a:1.0};
      }
      else if (util$3.isValidRGBA(color) === true) {
        let rgbaArray = color.substr(5).substr(0, color.length - 6).split(',');
        rgba = {r:rgbaArray[0], g:rgbaArray[1], b:rgbaArray[2], a:rgbaArray[3]};
      }
      else if (util$3.isValidHex(color) === true) {
        let rgbObj = util$3.hexToRGB(color);
        rgba = {r:rgbObj.r, g:rgbObj.g, b:rgbObj.b, a:1.0};
      }
    }
    else {
      if (color instanceof Object) {
        if (color.r !== undefined && color.g !== undefined && color.b !== undefined) {
          let alpha = color.a !== undefined ? color.a : '1.0';
          rgba = {r:color.r, g:color.g, b:color.b, a:alpha};
        }
      }
    }

    // set color
    if (rgba === undefined) {
      throw new Error("Unknown color passed to the colorPicker. Supported are strings: rgb, hex, rgba. Object: rgb ({r:r,g:g,b:b,[a:a]}). Supplied: " + JSON.stringify(color));
    }
    else {
      this._setColor(rgba, setInitial);
    }
  }


  /**
   * this shows the color picker.
   * The hue circle is constructed once and stored.
   */
  show() {
    if (this.closeCallback !== undefined) {
      this.closeCallback();
      this.closeCallback = undefined;
    }

    this.applied = false;
    this.frame.style.display = 'block';
    this._generateHueCircle();
  }

  // ------------------------------------------ PRIVATE ----------------------------- //

  /**
   * Hide the picker. Is called by the cancel button.
   * Optional boolean to store the previous color for easy access later on.
   * @param {boolean} [storePrevious=true]
   * @private
   */
  _hide(storePrevious = true) {
    // store the previous color for next time;
    if (storePrevious === true) {
      this.previousColor = util$3.extend({}, this.color);
    }

    if (this.applied === true) {
      this.updateCallback(this.initialColor);
    }

    this.frame.style.display = 'none';

    // call the closing callback, restoring the onclick method.
    // this is in a setTimeout because it will trigger the show again before the click is done.
    setTimeout(() => {
      if (this.closeCallback !== undefined) {
        this.closeCallback();
        this.closeCallback = undefined;
      }
    },0);
  }


  /**
   * bound to the save button. Saves and hides.
   * @private
   */
  _save() {
    this.updateCallback(this.color);
    this.applied = false;
    this._hide();
  }


  /**
   * Bound to apply button. Saves but does not close. Is undone by the cancel button.
   * @private
   */
  _apply() {
    this.applied = true;
    this.updateCallback(this.color);
    this._updatePicker(this.color);
  }


  /**
   * load the color from the previous session.
   * @private
   */
  _loadLast() {
    if (this.previousColor !== undefined) {
      this.setColor(this.previousColor, false);
    }
    else {
      alert("There is no last color to load...");
    }
  }


  /**
   * set the color, place the picker
   * @param {Object} rgba
   * @param {boolean} [setInitial=true]
   * @private
   */
  _setColor(rgba, setInitial = true) {
    // store the initial color
    if (setInitial === true) {
      this.initialColor = util$3.extend({}, rgba);
    }

    this.color = rgba;
    let hsv = util$3.RGBToHSV(rgba.r, rgba.g, rgba.b);

    let angleConvert = 2 * Math.PI;
    let radius = this.r * hsv.s;
    let x = this.centerCoordinates.x + radius * Math.sin(angleConvert * hsv.h);
    let y = this.centerCoordinates.y + radius * Math.cos(angleConvert * hsv.h);

    this.colorPickerSelector.style.left = x - 0.5 * this.colorPickerSelector.clientWidth + 'px';
    this.colorPickerSelector.style.top = y - 0.5 * this.colorPickerSelector.clientHeight + 'px';

    this._updatePicker(rgba);
  }


  /**
   * bound to opacity control
   * @param {number} value
   * @private
   */
  _setOpacity(value) {
    this.color.a = value / 100;
    this._updatePicker(this.color);
  }


  /**
   * bound to brightness control
   * @param {number} value
   * @private
   */
  _setBrightness(value) {
    let hsv = util$3.RGBToHSV(this.color.r, this.color.g, this.color.b);
    hsv.v = value / 100;
    let rgba = util$3.HSVToRGB(hsv.h, hsv.s, hsv.v);
    rgba['a'] = this.color.a;
    this.color = rgba;
    this._updatePicker();
  }


  /**
   * update the color picker. A black circle overlays the hue circle to mimic the brightness decreasing.
   * @param {Object} rgba
   * @private
   */
  _updatePicker(rgba = this.color) {
    let hsv = util$3.RGBToHSV(rgba.r, rgba.g, rgba.b);
    let ctx = this.colorPickerCanvas.getContext('2d');
    if (this.pixelRation === undefined) {
      this.pixelRatio = (window.devicePixelRatio || 1) / (ctx.webkitBackingStorePixelRatio ||
      ctx.mozBackingStorePixelRatio ||
      ctx.msBackingStorePixelRatio ||
      ctx.oBackingStorePixelRatio ||
      ctx.backingStorePixelRatio || 1);
    }
    ctx.setTransform(this.pixelRatio, 0, 0, this.pixelRatio, 0, 0);

    // clear the canvas
    let w = this.colorPickerCanvas.clientWidth;
    let h = this.colorPickerCanvas.clientHeight;
    ctx.clearRect(0, 0, w, h);

    ctx.putImageData(this.hueCircle, 0,0);
    ctx.fillStyle = 'rgba(0,0,0,' + (1- hsv.v) + ')';
    ctx.circle(this.centerCoordinates.x, this.centerCoordinates.y, this.r);
    ctx.fill();

    this.brightnessRange.value = 100 * hsv.v;
    this.opacityRange.value    = 100 * rgba.a;

    this.initialColorDiv.style.backgroundColor = 'rgba(' + this.initialColor.r + ',' + this.initialColor.g + ',' + this.initialColor.b + ',' + this.initialColor.a + ')';
    this.newColorDiv.style.backgroundColor = 'rgba(' + this.color.r + ',' + this.color.g + ',' + this.color.b + ',' + this.color.a + ')';
  }


  /**
   * used by create to set the size of the canvas.
   * @private
   */
  _setSize() {
    this.colorPickerCanvas.style.width = '100%';
    this.colorPickerCanvas.style.height = '100%';

    this.colorPickerCanvas.width = 289 * this.pixelRatio;
    this.colorPickerCanvas.height = 289 * this.pixelRatio;
  }


  /**
   * create all dom elements
   * TODO: cleanup, lots of similar dom elements
   * @private
   */
  _create() {
    this.frame = document.createElement('div');
    this.frame.className = 'vis-color-picker';

    this.colorPickerDiv = document.createElement('div');
    this.colorPickerSelector = document.createElement('div');
    this.colorPickerSelector.className = 'vis-selector';
    this.colorPickerDiv.appendChild(this.colorPickerSelector);

    this.colorPickerCanvas = document.createElement('canvas');
    this.colorPickerDiv.appendChild(this.colorPickerCanvas);

    if (!this.colorPickerCanvas.getContext) {
      let noCanvas = document.createElement( 'DIV' );
      noCanvas.style.color = 'red';
      noCanvas.style.fontWeight =  'bold' ;
      noCanvas.style.padding =  '10px';
      noCanvas.innerHTML =  'Error: your browser does not support HTML canvas';
      this.colorPickerCanvas.appendChild(noCanvas);
    }
    else {
      let ctx = this.colorPickerCanvas.getContext("2d");
      this.pixelRatio = (window.devicePixelRatio || 1) / (ctx.webkitBackingStorePixelRatio ||
      ctx.mozBackingStorePixelRatio ||
      ctx.msBackingStorePixelRatio ||
      ctx.oBackingStorePixelRatio ||
      ctx.backingStorePixelRatio || 1);
      this.colorPickerCanvas.getContext("2d").setTransform(this.pixelRatio, 0, 0, this.pixelRatio, 0, 0);
    }

    this.colorPickerDiv.className = 'vis-color';

    this.opacityDiv = document.createElement('div');
    this.opacityDiv.className = 'vis-opacity';

    this.brightnessDiv = document.createElement('div');
    this.brightnessDiv.className = 'vis-brightness';

    this.arrowDiv = document.createElement('div');
    this.arrowDiv.className = 'vis-arrow';

    this.opacityRange = document.createElement('input');
    try {
      this.opacityRange.type = 'range'; // Not supported on IE9
      this.opacityRange.min = '0';
      this.opacityRange.max = '100';
    }
    // TODO: Add some error handling and remove this lint exception
    catch (err) {}  // eslint-disable-line no-empty
    this.opacityRange.value = '100';
    this.opacityRange.className = 'vis-range';

    this.brightnessRange = document.createElement('input');
    try {
      this.brightnessRange.type = 'range'; // Not supported on IE9
      this.brightnessRange.min = '0';
      this.brightnessRange.max = '100';
    }
    // TODO: Add some error handling and remove this lint exception
    catch (err) {}  // eslint-disable-line no-empty
    this.brightnessRange.value = '100';
    this.brightnessRange.className = 'vis-range';

    this.opacityDiv.appendChild(this.opacityRange);
    this.brightnessDiv.appendChild(this.brightnessRange);

    var me = this;
    this.opacityRange.onchange = function () {me._setOpacity(this.value);};
    this.opacityRange.oninput  = function () {me._setOpacity(this.value);};
    this.brightnessRange.onchange = function () {me._setBrightness(this.value);};
    this.brightnessRange.oninput  = function () {me._setBrightness(this.value);};

    this.brightnessLabel = document.createElement("div");
    this.brightnessLabel.className = "vis-label vis-brightness";
    this.brightnessLabel.innerHTML = 'brightness:';

    this.opacityLabel = document.createElement("div");
    this.opacityLabel.className = "vis-label vis-opacity";
    this.opacityLabel.innerHTML = 'opacity:';

    this.newColorDiv = document.createElement("div");
    this.newColorDiv.className = "vis-new-color";
    this.newColorDiv.innerHTML = 'new';

    this.initialColorDiv = document.createElement("div");
    this.initialColorDiv.className = "vis-initial-color";
    this.initialColorDiv.innerHTML = 'initial';

    this.cancelButton = document.createElement("div");
    this.cancelButton.className = "vis-button vis-cancel";
    this.cancelButton.innerHTML = 'cancel';
    this.cancelButton.onclick = this._hide.bind(this, false);

    this.applyButton = document.createElement("div");
    this.applyButton.className = "vis-button vis-apply";
    this.applyButton.innerHTML = 'apply';
    this.applyButton.onclick = this._apply.bind(this);

    this.saveButton = document.createElement("div");
    this.saveButton.className = "vis-button vis-save";
    this.saveButton.innerHTML = 'save';
    this.saveButton.onclick = this._save.bind(this);

    this.loadButton = document.createElement("div");
    this.loadButton.className = "vis-button vis-load";
    this.loadButton.innerHTML = 'load last';
    this.loadButton.onclick = this._loadLast.bind(this);

    this.frame.appendChild(this.colorPickerDiv);
    this.frame.appendChild(this.arrowDiv);
    this.frame.appendChild(this.brightnessLabel);
    this.frame.appendChild(this.brightnessDiv);
    this.frame.appendChild(this.opacityLabel);
    this.frame.appendChild(this.opacityDiv);
    this.frame.appendChild(this.newColorDiv);
    this.frame.appendChild(this.initialColorDiv);

    this.frame.appendChild(this.cancelButton);
    this.frame.appendChild(this.applyButton);
    this.frame.appendChild(this.saveButton);
    this.frame.appendChild(this.loadButton);
  }


  /**
   * bind hammer to the color picker
   * @private
   */
  _bindHammer() {
    this.drag = {};
    this.pinch = {};
    this.hammer = new Hammer$2(this.colorPickerCanvas);
    this.hammer.get('pinch').set({enable: true});

    onTouch(this.hammer, (event) => {this._moveSelector(event);});
    this.hammer.on('tap',       (event) => {this._moveSelector(event);});
    this.hammer.on('panstart',  (event) => {this._moveSelector(event);});
    this.hammer.on('panmove',   (event) => {this._moveSelector(event);});
    this.hammer.on('panend',    (event) => {this._moveSelector(event);});
  }


  /**
   * generate the hue circle. This is relatively heavy (200ms) and is done only once on the first time it is shown.
   * @private
   */
  _generateHueCircle() {
    if (this.generated === false) {
      let ctx = this.colorPickerCanvas.getContext('2d');
      if (this.pixelRation === undefined) {
        this.pixelRatio = (window.devicePixelRatio || 1) / (ctx.webkitBackingStorePixelRatio ||
        ctx.mozBackingStorePixelRatio ||
        ctx.msBackingStorePixelRatio ||
        ctx.oBackingStorePixelRatio ||
        ctx.backingStorePixelRatio || 1);
      }
      ctx.setTransform(this.pixelRatio, 0, 0, this.pixelRatio, 0, 0);

      // clear the canvas
      let w = this.colorPickerCanvas.clientWidth;
      let h = this.colorPickerCanvas.clientHeight;
      ctx.clearRect(0, 0, w, h);


      // draw hue circle
      let x, y, hue, sat;
      this.centerCoordinates = {x: w * 0.5, y: h * 0.5};
      this.r = 0.49 * w;
      let angleConvert = (2 * Math.PI) / 360;
      let hfac = 1 / 360;
      let sfac = 1 / this.r;
      let rgb;
      for (hue = 0; hue < 360; hue++) {
        for (sat = 0; sat < this.r; sat++) {
          x = this.centerCoordinates.x + sat * Math.sin(angleConvert * hue);
          y = this.centerCoordinates.y + sat * Math.cos(angleConvert * hue);
          rgb = util$3.HSVToRGB(hue * hfac, sat * sfac, 1);
          ctx.fillStyle = 'rgb(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ')';
          ctx.fillRect(x - 0.5, y - 0.5, 2, 2);
        }
      }
      ctx.strokeStyle = 'rgba(0,0,0,1)';
      ctx.circle(this.centerCoordinates.x, this.centerCoordinates.y, this.r);
      ctx.stroke();

      this.hueCircle = ctx.getImageData(0,0,w,h);
    }
    this.generated = true;
  }


  /**
   * move the selector. This is called by hammer functions.
   *
   * @param {Event}  event   The event
   * @private
   */
  _moveSelector(event) {
    let rect = this.colorPickerDiv.getBoundingClientRect();
    let left = event.center.x - rect.left;
    let top = event.center.y - rect.top;

    let centerY = 0.5 * this.colorPickerDiv.clientHeight;
    let centerX = 0.5 * this.colorPickerDiv.clientWidth;

    let x = left - centerX;
    let y = top - centerY;

    let angle = Math.atan2(x,y);
    let radius = 0.98 * Math.min(Math.sqrt(x * x + y * y), centerX);

    let newTop = Math.cos(angle) * radius + centerY;
    let newLeft = Math.sin(angle) * radius + centerX;

    this.colorPickerSelector.style.top = newTop - 0.5 * this.colorPickerSelector.clientHeight + 'px';
    this.colorPickerSelector.style.left = newLeft - 0.5 * this.colorPickerSelector.clientWidth + 'px';

    // set color
    let h = angle / (2 * Math.PI);
    h = h < 0 ? h + 1 : h;
    let s = radius / this.r;
    let hsv = util$3.RGBToHSV(this.color.r, this.color.g, this.color.b);
    hsv.h = h;
    hsv.s = s;
    let rgba = util$3.HSVToRGB(hsv.h, hsv.s, hsv.v);
    rgba['a'] = this.color.a;
    this.color = rgba;

    // update previews
    this.initialColorDiv.style.backgroundColor = 'rgba(' + this.initialColor.r + ',' + this.initialColor.g + ',' + this.initialColor.b + ',' + this.initialColor.a + ')';
    this.newColorDiv.style.backgroundColor = 'rgba(' + this.color.r + ',' + this.color.g + ',' + this.color.b + ',' + this.color.a + ')';
  }
}

/**
 * The way this works is for all properties of this.possible options, you can supply the property name in any form to list the options.
 * Boolean options are recognised as Boolean
 * Number options should be written as array: [default value, min value, max value, stepsize]
 * Colors should be written as array: ['color', '#ffffff']
 * Strings with should be written as array: [option1, option2, option3, ..]
 *
 * The options are matched with their counterparts in each of the modules and the values used in the configuration are
 */
class Configurator$2 {
  /**
   * @param {Object} parentModule        | the location where parentModule.setOptions() can be called
   * @param {Object} defaultContainer    | the default container of the module
   * @param {Object} configureOptions    | the fully configured and predefined options set found in allOptions.js
   * @param {number} pixelRatio          | canvas pixel ratio
   */
  constructor(parentModule, defaultContainer, configureOptions, pixelRatio = 1) {
    this.parent = parentModule;
    this.changedOptions = [];
    this.container = defaultContainer;
    this.allowCreation = false;

    this.options = {};
    this.initialized = false;
    this.popupCounter = 0;
    this.defaultOptions = {
      enabled: false,
      filter: true,
      container: undefined,
      showButton: true
    };
    util$3.extend(this.options, this.defaultOptions);

    this.configureOptions = configureOptions;
    this.moduleOptions = {};
    this.domElements = [];
    this.popupDiv = {};
    this.popupLimit = 5;
    this.popupHistory = {};
    this.colorPicker = new ColorPicker$2(pixelRatio);
    this.wrapper = undefined;
  }


  /**
   * refresh all options.
   * Because all modules parse their options by themselves, we just use their options. We copy them here.
   *
   * @param {Object} options
   */
  setOptions(options) {
    if (options !== undefined) {
      // reset the popup history because the indices may have been changed.
      this.popupHistory = {};
      this._removePopup();

      let enabled = true;
      if (typeof options === 'string') {
        this.options.filter = options;
      }
      else if (Array.isArray(options)) {
        this.options.filter = options.join();
      }
      else if (typeof options === 'object') {
        if (options == null) {
          throw new TypeError('options cannot be null');
        }
        if (options.container !== undefined) {
          this.options.container = options.container;
        }
        if (options.filter !== undefined) {
          this.options.filter = options.filter;
        }
        if (options.showButton !== undefined) {
          this.options.showButton = options.showButton;
        }
        if (options.enabled !== undefined) {
          enabled = options.enabled;
        }
      }
      else if (typeof options === 'boolean') {
        this.options.filter = true;
        enabled = options;
      }
      else if (typeof options === 'function') {
        this.options.filter = options;
        enabled = true;
      }
      if (this.options.filter === false) {
        enabled = false;
      }

      this.options.enabled = enabled;
    }
    this._clean();
  }

  /**
   *
   * @param {Object} moduleOptions
   */
  setModuleOptions(moduleOptions) {
    this.moduleOptions = moduleOptions;
    if (this.options.enabled === true) {
      this._clean();
      if (this.options.container !== undefined) {
        this.container = this.options.container;
      }
      this._create();
    }
  }

  /**
   * Create all DOM elements
   * @private
   */
  _create() {
    this._clean();
    this.changedOptions = [];

    let filter = this.options.filter;
    let counter = 0;
    let show = false;
    for (let option in this.configureOptions) {
      if (this.configureOptions.hasOwnProperty(option)) {
        this.allowCreation = false;
        show = false;
        if (typeof filter === 'function') {
          show = filter(option,[]);
          show = show || this._handleObject(this.configureOptions[option], [option], true);
        }
        else if (filter === true || filter.indexOf(option) !== -1) {
          show = true;
        }

        if (show !== false) {
          this.allowCreation = true;

          // linebreak between categories
          if (counter > 0) {
            this._makeItem([]);
          }
          // a header for the category
          this._makeHeader(option);

          // get the sub options
          this._handleObject(this.configureOptions[option], [option]);
        }
        counter++;
      }
    }
    this._makeButton();
    this._push();
    //~ this.colorPicker.insertTo(this.container);
  }


  /**
   * draw all DOM elements on the screen
   * @private
   */
  _push() {
    this.wrapper = document.createElement('div');
    this.wrapper.className = 'vis-configuration-wrapper';
    this.container.appendChild(this.wrapper);
    for (var i = 0; i < this.domElements.length; i++) {
      this.wrapper.appendChild(this.domElements[i]);
    }

    this._showPopupIfNeeded();
  }


  /**
   * delete all DOM elements
   * @private
   */
  _clean() {
    for (var i = 0; i < this.domElements.length; i++) {
      this.wrapper.removeChild(this.domElements[i]);
    }

    if (this.wrapper !== undefined) {
      this.container.removeChild(this.wrapper);
      this.wrapper = undefined;
    }
    this.domElements = [];

    this._removePopup();
  }


  /**
   * get the value from the actualOptions if it exists
   * @param {array} path    | where to look for the actual option
   * @returns {*}
   * @private
   */
  _getValue(path) {
    let base = this.moduleOptions;
    for (let i = 0; i < path.length; i++) {
      if (base[path[i]] !== undefined) {
        base = base[path[i]];
      }
      else {
        base = undefined;
        break;
      }
    }
    return base;
  }


  /**
   * all option elements are wrapped in an item
   * @param {Array} path    | where to look for the actual option
   * @param {Array.<Element>} domElements
   * @returns {number}
   * @private
   */
  _makeItem(path, ...domElements) {
    if (this.allowCreation === true) {
      let item = document.createElement('div');
      item.className = 'vis-configuration vis-config-item vis-config-s' + path.length;
      domElements.forEach((element) => {
        item.appendChild(element);
      });
      this.domElements.push(item);
      return this.domElements.length;
    }
    return 0;
  }


  /**
   * header for major subjects
   * @param {string} name
   * @private
   */
  _makeHeader(name) {
    let div = document.createElement('div');
    div.className = 'vis-configuration vis-config-header';
    div.innerHTML = util$3.xss(name);
    this._makeItem([],div);
  }


  /**
   * make a label, if it is an object label, it gets different styling.
   * @param {string} name
   * @param {array} path    | where to look for the actual option
   * @param {string} objectLabel
   * @returns {HTMLElement}
   * @private
   */
  _makeLabel(name, path, objectLabel = false) {
    let div = document.createElement('div');
    div.className = 'vis-configuration vis-config-label vis-config-s' + path.length;
    if (objectLabel === true) {
      div.innerHTML = util$3.xss('<i><b>' + name + ':</b></i>');
    }
    else {
      div.innerHTML = util$3.xss(name + ':');
    }
    return div;
  }


  /**
   * make a dropdown list for multiple possible string optoins
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _makeDropdown(arr, value, path) {
    let select = document.createElement('select');
    select.className = 'vis-configuration vis-config-select';
    let selectedValue = 0;
    if (value !== undefined) {
      if (arr.indexOf(value) !== -1) {
        selectedValue = arr.indexOf(value);
      }
    }

    for (let i = 0; i < arr.length; i++) {
      let option = document.createElement('option');
      option.value = arr[i];
      if (i === selectedValue) {
        option.selected = 'selected';
      }
      option.innerHTML = arr[i];
      select.appendChild(option);
    }

    let me = this;
    select.onchange = function () {me._update(this.value, path);};

    let label = this._makeLabel(path[path.length-1], path);
    this._makeItem(path, label, select);
  }


  /**
   * make a range object for numeric options
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _makeRange(arr, value, path) {
    let defaultValue = arr[0];
    let min = arr[1];
    let max = arr[2];
    let step = arr[3];
    let range = document.createElement('input');
    range.className = 'vis-configuration vis-config-range';
    try {
      range.type = 'range'; // not supported on IE9
      range.min = min;
      range.max = max;
    }
    // TODO: Add some error handling and remove this lint exception
    catch (err) {}  // eslint-disable-line no-empty
    range.step = step;

    // set up the popup settings in case they are needed.
    let popupString = '';
    let popupValue = 0;

    if (value !== undefined) {
      let factor = 1.20;
      if (value < 0 && value * factor < min) {
        range.min = Math.ceil(value * factor);
        popupValue = range.min;
        popupString = 'range increased';
      }
      else if (value / factor < min) {
        range.min = Math.ceil(value / factor);
        popupValue = range.min;
        popupString = 'range increased';
      }
      if (value * factor > max && max !== 1) {
        range.max = Math.ceil(value * factor);
        popupValue = range.max;
        popupString = 'range increased';
      }
      range.value = value;
    }
    else {
      range.value = defaultValue;
    }

    let input = document.createElement('input');
    input.className = 'vis-configuration vis-config-rangeinput';
    input.value = Number(range.value);

    var me = this;
    range.onchange = function () {input.value = this.value; me._update(Number(this.value), path);};
    range.oninput  = function () {input.value = this.value; };

    let label = this._makeLabel(path[path.length-1], path);
    let itemIndex = this._makeItem(path, label, range, input);

    // if a popup is needed AND it has not been shown for this value, show it.
    if (popupString !== '' && this.popupHistory[itemIndex] !== popupValue) {
      this.popupHistory[itemIndex] = popupValue;
      this._setupPopup(popupString, itemIndex);
    }
  }

  /**
   * make a button object
   * @private
   */
  _makeButton() {
    if (this.options.showButton === true) {
      let generateButton = document.createElement('div');
      generateButton.className = 'vis-configuration vis-config-button';
      generateButton.innerHTML = 'generate options';
      generateButton.onclick =     () => {this._printOptions();};
      generateButton.onmouseover = () => {generateButton.className = 'vis-configuration vis-config-button hover';};
      generateButton.onmouseout =  () => {generateButton.className = 'vis-configuration vis-config-button';};

      this.optionsContainer = document.createElement('div');
      this.optionsContainer.className = 'vis-configuration vis-config-option-container';

      this.domElements.push(this.optionsContainer);
      this.domElements.push(generateButton);
    }
  }


  /**
   * prepare the popup
   * @param {string} string
   * @param {number} index
   * @private
   */
  _setupPopup(string, index) {
    if (this.initialized === true && this.allowCreation === true && this.popupCounter < this.popupLimit) {
      let div = document.createElement("div");
      div.id = "vis-configuration-popup";
      div.className = "vis-configuration-popup";
      div.innerHTML = util$3.xss(string);
      div.onclick = () => {this._removePopup();};
      this.popupCounter += 1;
      this.popupDiv = {html:div, index:index};
    }
  }


  /**
   * remove the popup from the dom
   * @private
   */
  _removePopup() {
    if (this.popupDiv.html !== undefined) {
      this.popupDiv.html.parentNode.removeChild(this.popupDiv.html);
      clearTimeout(this.popupDiv.hideTimeout);
      clearTimeout(this.popupDiv.deleteTimeout);
      this.popupDiv = {};
    }
  }


  /**
   * Show the popup if it is needed.
   * @private
   */
  _showPopupIfNeeded() {
    if (this.popupDiv.html !== undefined) {
      let correspondingElement = this.domElements[this.popupDiv.index];
      let rect = correspondingElement.getBoundingClientRect();
      this.popupDiv.html.style.left = rect.left + "px";
      this.popupDiv.html.style.top = rect.top - 30 + "px"; // 30 is the height;
      document.body.appendChild(this.popupDiv.html);
      this.popupDiv.hideTimeout = setTimeout(() => {
        this.popupDiv.html.style.opacity = 0;
      },1500);
      this.popupDiv.deleteTimeout = setTimeout(() => {
        this._removePopup();
      },1800);
    }
  }

  /**
   * make a checkbox for boolean options.
   * @param {number} defaultValue
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _makeCheckbox(defaultValue, value, path) {
    var checkbox = document.createElement('input');
    checkbox.type = 'checkbox';
    checkbox.className = 'vis-configuration vis-config-checkbox';
    checkbox.checked = defaultValue;
    if (value !== undefined) {
      checkbox.checked = value;
      if (value !== defaultValue) {
        if (typeof defaultValue === 'object') {
          if (value !== defaultValue.enabled) {
            this.changedOptions.push({path:path, value:value});
          }
        }
        else {
          this.changedOptions.push({path:path, value:value});
        }
      }
    }

    let me = this;
    checkbox.onchange = function() {me._update(this.checked, path);};

    let label = this._makeLabel(path[path.length-1], path);
    this._makeItem(path, label, checkbox);
  }

  /**
   * make a text input field for string options.
   * @param {number} defaultValue
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _makeTextInput(defaultValue, value, path) {
    var checkbox = document.createElement('input');
    checkbox.type = 'text';
    checkbox.className = 'vis-configuration vis-config-text';
    checkbox.value = value;
    if (value !== defaultValue) {
      this.changedOptions.push({path:path, value:value});
    }

    let me = this;
    checkbox.onchange = function() {me._update(this.value, path);};

    let label = this._makeLabel(path[path.length-1], path);
    this._makeItem(path, label, checkbox);
  }


  /**
   * make a color field with a color picker for color fields
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _makeColorField(arr, value, path) {
    let defaultColor = arr[1];
    let div = document.createElement('div');
    value = value === undefined ? defaultColor : value;

    if (value !== 'none') {
      div.className = 'vis-configuration vis-config-colorBlock';
      div.style.backgroundColor = value;
    }
    else {
      div.className = 'vis-configuration vis-config-colorBlock none';
    }

    value = value === undefined ? defaultColor : value;
    div.onclick = () => {
      this._showColorPicker(value,div,path);
    };

    let label = this._makeLabel(path[path.length-1], path);
    this._makeItem(path,label, div);
  }


  /**
   * used by the color buttons to call the color picker.
   * @param {number} value
   * @param {HTMLElement} div
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _showColorPicker(value, div, path) {
    // clear the callback from this div
    div.onclick = function() {};

    this.colorPicker.insertTo(div);
    this.colorPicker.show();

    this.colorPicker.setColor(value);
    this.colorPicker.setUpdateCallback((color) => {
      let colorString = 'rgba(' + color.r + ',' + color.g + ',' + color.b + ',' + color.a + ')';
      div.style.backgroundColor = colorString;
      this._update(colorString,path);
    });

    // on close of the colorpicker, restore the callback.
    this.colorPicker.setCloseCallback(() => {
      div.onclick = () => {
        this._showColorPicker(value,div,path);
      };
    });
  }


  /**
   * parse an object and draw the correct items
   * @param {Object} obj
   * @param {array} [path=[]]    | where to look for the actual option
   * @param {boolean} [checkOnly=false]
   * @returns {boolean}
   * @private
   */
  _handleObject(obj, path = [], checkOnly = false) {
    let show = false;
    let filter = this.options.filter;
    let visibleInSet = false;
    for (let subObj in obj) {
      if (obj.hasOwnProperty(subObj)) {
        show = true;
        let item = obj[subObj];
        let newPath = util$3.copyAndExtendArray(path, subObj);
        if (typeof filter === 'function') {
          show = filter(subObj,path);

          // if needed we must go deeper into the object.
          if (show === false) {
            if (!Array.isArray(item) && typeof item !== 'string' && typeof item !== 'boolean' && item instanceof Object) {
              this.allowCreation = false;
              show = this._handleObject(item, newPath, true);
              this.allowCreation = checkOnly === false;
            }
          }
        }

        if (show !== false) {
          visibleInSet = true;
          let value = this._getValue(newPath);

          if (Array.isArray(item)) {
            this._handleArray(item, value, newPath);
          }
          else if (typeof item === 'string') {
            this._makeTextInput(item, value, newPath);
          }
          else if (typeof item === 'boolean') {
            this._makeCheckbox(item, value, newPath);
          }
          else if (item instanceof Object) {
            // collapse the physics options that are not enabled
            let draw = true;
            if (path.indexOf('physics') !== -1) {
              if (this.moduleOptions.physics.solver !== subObj) {
                draw = false;
              }
            }

            if (draw === true) {
              // initially collapse options with an disabled enabled option.
              if (item.enabled !== undefined) {
                let enabledPath = util$3.copyAndExtendArray(newPath, 'enabled');
                let enabledValue = this._getValue(enabledPath);
                if (enabledValue === true) {
                  let label = this._makeLabel(subObj, newPath, true);
                  this._makeItem(newPath, label);
                  visibleInSet = this._handleObject(item, newPath) || visibleInSet;
                }
                else {
                  this._makeCheckbox(item, enabledValue, newPath);
                }
              }
              else {
                let label = this._makeLabel(subObj, newPath, true);
                this._makeItem(newPath, label);
                visibleInSet = this._handleObject(item, newPath) || visibleInSet;
              }
            }
          }
          else {
            console.error('dont know how to handle', item, subObj, newPath);
          }
        }
      }
    }
    return visibleInSet;
  }


  /**
   * handle the array type of option
   * @param {Array.<number>} arr
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _handleArray(arr, value, path) {
    if (typeof arr[0] === 'string' && arr[0] === 'color') {
      this._makeColorField(arr, value, path);
      if (arr[1] !== value) {this.changedOptions.push({path:path, value:value});}
    }
    else if (typeof arr[0] === 'string') {
      this._makeDropdown(arr, value, path);
      if (arr[0] !== value) {this.changedOptions.push({path:path, value:value});}
    }
    else if (typeof arr[0] === 'number') {
      this._makeRange(arr, value, path);
      if (arr[0] !== value) {this.changedOptions.push({path:path, value:Number(value)});}
    }
  }



  /**
   * called to update the network with the new settings.
   * @param {number} value
   * @param {array} path    | where to look for the actual option
   * @private
   */
  _update(value, path) {
    let options = this._constructOptions(value,path);

    if (this.parent.body && this.parent.body.emitter && this.parent.body.emitter.emit) {
      this.parent.body.emitter.emit("configChange", options);
    }
    this.initialized = true;
    this.parent.setOptions(options);
  }


  /**
   *
   * @param {string|Boolean} value
   * @param {Array.<string>} path
   * @param {{}} optionsObj
   * @returns {{}}
   * @private
   */
  _constructOptions(value, path, optionsObj = {}) {
    let pointer = optionsObj;

    // when dropdown boxes can be string or boolean, we typecast it into correct types
    value = value === 'true'  ? true  : value;
    value = value === 'false' ? false : value;

    for (let i = 0; i < path.length; i++) {
      if (path[i] !== 'global') {
        if (pointer[path[i]] === undefined) {
          pointer[path[i]] = {};
        }
        if (i !== path.length - 1) {
          pointer = pointer[path[i]];
        }
        else {
          pointer[path[i]] = value;
        }
      }
    }
    return optionsObj;
  }

  /**
   * @private
   */
  _printOptions() {
    let options = this.getOptions();
    this.optionsContainer.innerHTML = '<pre>var options = ' + JSON.stringify(options, null, 2) + '</pre>';
  }

  /**
   *
   * @returns {{}} options
   */
  getOptions() {
    let options = {};
    for (var i = 0; i < this.changedOptions.length; i++) {
      this._constructOptions(this.changedOptions[i].value, this.changedOptions[i].path, options);
    }
    return options;
  }
}

/**
 * Create a timeline visualization
 * @extends Core
 */
class Timeline extends Core {
  /**
 * @param {HTMLElement} container
 * @param {vis.DataSet | vis.DataView | Array} [items]
 * @param {vis.DataSet | vis.DataView | Array} [groups]
 * @param {Object} [options]  See Timeline.setOptions for the available options.
 * @constructor Timeline
 */
  constructor(container, items, groups, options) {
    super();
    this.initTime = new Date();
    this.itemsDone = false;

    if (!(this instanceof Timeline)) {
      throw new SyntaxError('Constructor must be called with the new operator');
    }

    // if the third element is options, the forth is groups (optionally);
    if (!(Array.isArray(groups) || isDataViewLike("id", groups)) && groups instanceof Object) {
      const forthArgument = options;
      options = groups;
      groups = forthArgument;
    }

    // TODO: REMOVE THIS in the next MAJOR release
    // see https://github.com/almende/vis/issues/2511
    if (options && options.throttleRedraw) {
      console.warn("Timeline option \"throttleRedraw\" is DEPRICATED and no longer supported. It will be removed in the next MAJOR release.");
    }

    const me = this;
    this.defaultOptions = {
      autoResize: true,
      longSelectPressTime: 251,
      orientation: {
        axis: 'bottom',   // axis orientation: 'bottom', 'top', or 'both'
        item: 'bottom'    // not relevant
      },
      moment: moment$1,
    };
    this.options = util$3.deepExtend({}, this.defaultOptions);

    // Create the DOM, props, and emitter
    this._create(container);
    if (!options || (options && typeof options.rtl == "undefined")) {
      this.dom.root.style.visibility = 'hidden';
      let directionFromDom;
      let domNode = this.dom.root;
      while (!directionFromDom && domNode) {
        directionFromDom = window.getComputedStyle(domNode, null).direction;
        domNode = domNode.parentElement;
      }
      this.options.rtl = (directionFromDom && (directionFromDom.toLowerCase() == "rtl"));
    } else {
      this.options.rtl = options.rtl;
    }

    if (options) {
      if (options.rollingMode) { this.options.rollingMode = options.rollingMode; }
      if (options.onInitialDrawComplete) { this.options.onInitialDrawComplete = options.onInitialDrawComplete; }
      if (options.onTimeout) { this.options.onTimeout = options.onTimeout; }
      if (options.loadingScreenTemplate) { this.options.loadingScreenTemplate = options.loadingScreenTemplate; }
    }

    // Prepare loading screen
    const loadingScreenFragment = document.createElement('div');
    if (this.options.loadingScreenTemplate) {
      const templateFunction = this.options.loadingScreenTemplate.bind(this);
      const loadingScreen = templateFunction(this.dom.loadingScreen);
      if ((loadingScreen instanceof Object) && !(loadingScreen instanceof Element)) {
        templateFunction(loadingScreenFragment);
      } else {
        if (loadingScreen instanceof Element) {
          loadingScreenFragment.innerHTML = '';
          loadingScreenFragment.appendChild(loadingScreen);
        }
        else if (loadingScreen != undefined) {
          loadingScreenFragment.innerHTML = util$3.xss(loadingScreen);
        }
      }
    }
    this.dom.loadingScreen.appendChild(loadingScreenFragment);

    // all components listed here will be repainted automatically
    this.components = [];

    this.body = {
      dom: this.dom,
      domProps: this.props,
      emitter: {
        on: this.on.bind(this),
        off: this.off.bind(this),
        emit: this.emit.bind(this)
      },
      hiddenDates: [],
      util: {
        getScale() {
          return me.timeAxis.step.scale;
        },
        getStep() {
          return me.timeAxis.step.step;
        },

        toScreen: me._toScreen.bind(me),
        toGlobalScreen: me._toGlobalScreen.bind(me), // this refers to the root.width
        toTime: me._toTime.bind(me),
        toGlobalTime : me._toGlobalTime.bind(me)
      }
    };

    // range
    this.range = new Range(this.body, this.options);
    this.components.push(this.range);
    this.body.range = this.range;

    // time axis
    this.timeAxis = new TimeAxis(this.body, this.options);
    this.timeAxis2 = null; // used in case of orientation option 'both'
    this.components.push(this.timeAxis);

    // current time bar
    this.currentTime = new CurrentTime(this.body, this.options);
    this.components.push(this.currentTime);

    // item set
    this.itemSet = new ItemSet(this.body, this.options);
    this.components.push(this.itemSet);

    this.itemsData = null;      // DataSet
    this.groupsData = null;     // DataSet

    function emit(eventName, event) {
      if (!me.hasListeners(eventName)) {
        return;
      }

      me.emit(eventName, me.getEventProperties(event));
    }

    this.dom.root.onclick = event => {
      emit('click', event);
    };
    this.dom.root.ondblclick = event => {
      emit('doubleClick', event);
    };
    this.dom.root.oncontextmenu = event => {
      emit('contextmenu', event);
    };
    this.dom.root.onmouseover = event => {
      emit('mouseOver', event);
    };
    if(window.PointerEvent) {
      this.dom.root.onpointerdown = event => {
        emit('mouseDown', event);
      };
      this.dom.root.onpointermove = event => {
        emit('mouseMove', event);
      };
      this.dom.root.onpointerup = event => {
        emit('mouseUp', event);
      };
    } else {
      this.dom.root.onmousemove = event => {
        emit('mouseMove', event);
      };
      this.dom.root.onmousedown = event => {
        emit('mouseDown', event);
      };
      this.dom.root.onmouseup = event => {
        emit('mouseUp', event);
      };
    }

    //Single time autoscale/fit
    this.initialFitDone = false;
    this.on('changed', () => {
      if (me.itemsData == null) return;
      if (!me.initialFitDone && !me.options.rollingMode) {
        me.initialFitDone = true;
        if (me.options.start != undefined || me.options.end != undefined) {
          if (me.options.start == undefined || me.options.end == undefined) {
            var range = me.getItemRange();
          }

          const start = me.options.start != undefined ? me.options.start : range.min;
          const end   = me.options.end   != undefined ? me.options.end   : range.max;
          me.setWindow(start, end, {animation: false});
        } else {
          me.fit({animation: false});
        }
      }

      if (!me.initialDrawDone && (me.initialRangeChangeDone || (!me.options.start && !me.options.end) 
        || me.options.rollingMode)) {
        me.initialDrawDone = true;
        me.itemSet.initialDrawDone = true;
        me.dom.root.style.visibility = 'visible';
        me.dom.loadingScreen.parentNode.removeChild(me.dom.loadingScreen);
        if (me.options.onInitialDrawComplete) {
          setTimeout(() => {
            return me.options.onInitialDrawComplete();
          }, 0);
        }
      }
    });

    this.on('destroyTimeline', () => {
      me.destroy();
    });

    // apply options
    if (options) {
      this.setOptions(options);
    }

    this.body.emitter.on('fit', (args) => {
      this._onFit(args);
      this.redraw();
    });

    // IMPORTANT: THIS HAPPENS BEFORE SET ITEMS!
    if (groups) {
      this.setGroups(groups);
    }

    // create itemset
    if (items) {
      this.setItems(items);
    }

    // draw for the first time
    this._redraw();
  }

  /**
   * Load a configurator
   * @return {Object}
   * @private
   */
  _createConfigurator() {
    return new Configurator$2(this, this.dom.container, configureOptions);
  }

  /**
   * Force a redraw. The size of all items will be recalculated.
   * Can be useful to manually redraw when option autoResize=false and the window
   * has been resized, or when the items CSS has been changed.
   *
   * Note: this function will be overridden on construction with a trottled version
   */
  redraw() {
    this.itemSet && this.itemSet.markDirty({refreshItems: true});
    this._redraw();
  }

  /**
   * Remove an item from the group
   * @param {object} options
   */
  setOptions(options) {
    // validate options
    let errorFound = Validator$2.validate(options, allOptions$1$1);

    if (errorFound === true) {
      console.log('%cErrors have been found in the supplied options object.', printStyle);
    }

    Core.prototype.setOptions.call(this, options);

    if ('type' in options) {
      if (options.type !== this.options.type) {
        this.options.type = options.type;

        // force recreation of all items
        const itemsData = this.itemsData;
        if (itemsData) {
          const selection = this.getSelection();
          this.setItems(null);            // remove all
          this.setItems(itemsData.rawDS); // add all
          this.setSelection(selection);   // restore selection
        }
      }
    }
  }

  /**
   * Set items
   * @param {vis.DataSet | Array | null} items
   */
  setItems(items) {
    this.itemsDone = false;
    
    // convert to type DataSet when needed
    let newDataSet;
    if (!items) {
      newDataSet = null;
    }
    else if (isDataViewLike("id", items)) {
      newDataSet = typeCoerceDataSet(items);
    }
    else {
      // turn an array into a dataset
      newDataSet = typeCoerceDataSet(new DataSet(items));
    }

    // set items
    if (this.itemsData) {
      // stop maintaining a coerced version of the old data set
      this.itemsData.dispose();
    }
    this.itemsData = newDataSet;
    this.itemSet && this.itemSet.setItems(newDataSet != null ? newDataSet.rawDS : null);
  }

  /**
   * Set groups
   * @param {vis.DataSet | Array} groups
   */
  setGroups(groups) {
    // convert to type DataSet when needed
    let newDataSet;
    const filter = group => group.visible !== false;
    
    if (!groups) {
      newDataSet = null;
    }
    else {
      // If groups is array, turn to DataSet & build dataview from that
      if (Array.isArray(groups)) groups = new DataSet(groups);
      
      newDataSet = new DataView(groups,{filter});
    }

    // This looks weird but it's necessary to prevent memory leaks.
    //
    // The problem is that the DataView will exist as long as the DataSet it's
    // connected to. This will force it to swap the groups DataSet for it's own
    // DataSet. In this arrangement it will become unreferenced from the outside
    // and garbage collected.
    //
    // IMPORTANT NOTE: If `this.groupsData` is a DataView was created in this
    // method. Even if the original is a DataView already a new one has been
    // created and assigned to `this.groupsData`. In case this changes in the
    // future it will be necessary to rework this!!!!
    if (this.groupsData != null && typeof this.groupsData.setData === "function") {
      this.groupsData.setData(null);
    }
    this.groupsData = newDataSet;
    this.itemSet.setGroups(newDataSet);
  }

  /**
   * Set both items and groups in one go
   * @param {{items: (Array | vis.DataSet), groups: (Array | vis.DataSet)}} data
   */
  setData(data) {
    if (data && data.groups) {
      this.setGroups(data.groups);
    }

    if (data && data.items) {
      this.setItems(data.items);
    }
  }

  /**
   * Set selected items by their id. Replaces the current selection
   * Unknown id's are silently ignored.
   * @param {string[] | string} [ids]  An array with zero or more id's of the items to be
   *                                selected. If ids is an empty array, all items will be
   *                                unselected.
   * @param {Object} [options]      Available options:
   *                                `focus: boolean`
   *                                    If true, focus will be set to the selected item(s)
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   *                                    Only applicable when option focus is true.
   */
  setSelection(ids, options) {
    this.itemSet && this.itemSet.setSelection(ids);

    if (options && options.focus) {
      this.focus(ids, options);
    }
  }

  /**
   * Get the selected items by their id
   * @return {Array} ids  The ids of the selected items
   */
  getSelection() {
    return this.itemSet && this.itemSet.getSelection() || [];
  }

  /**
   * Adjust the visible window such that the selected item (or multiple items)
   * are centered on screen.
   * @param {string | String[]} id     An item id or array with item ids
   * @param {Object} [options]      Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   *                                `zoom: boolean`
   *                                    If true (default), the timeline will
   *                                    zoom on the element after focus it.
   */
  focus(id, options) {
    if (!this.itemsData || id == undefined) return;

    const ids = Array.isArray(id) ? id : [id];

    // get the specified item(s)
    const itemsData = this.itemsData.get(ids);

    // calculate minimum start and maximum end of specified items
    let start = null;
    let end = null;
    itemsData.forEach(itemData => {
      const s = itemData.start.valueOf();
      const e = 'end' in itemData ? itemData.end.valueOf() : itemData.start.valueOf();

      if (start === null || s < start) {
        start = s;
      }

      if (end === null || e > end) {
        end = e;
      }
    });


    if (start !== null && end !== null) {
      const me = this;
      // Use the first item for the vertical focus
      const item = this.itemSet.items[ids[0]];
      let startPos = this._getScrollTop() * -1;
      let initialVerticalScroll = null;

      // Setup a handler for each frame of the vertical scroll
      const verticalAnimationFrame = (ease, willDraw, done) => {
        const verticalScroll = getItemVerticalScroll(me, item);

        if (verticalScroll === false) {
          return; // We don't need to scroll, so do nothing
        }

        if(!initialVerticalScroll) {
          initialVerticalScroll = verticalScroll;
        }

        if(initialVerticalScroll.itemTop == verticalScroll.itemTop && !initialVerticalScroll.shouldScroll) {
          return; // We don't need to scroll, so do nothing
        }
        else if(initialVerticalScroll.itemTop != verticalScroll.itemTop && verticalScroll.shouldScroll) {
          // The redraw shifted elements, so reset the animation to correct
          initialVerticalScroll = verticalScroll;
          startPos = me._getScrollTop() * -1;
        }      

        const from = startPos;
        const to = initialVerticalScroll.scrollOffset;
        const scrollTop = done ? to : (from + (to - from) * ease);

        me._setScrollTop(-scrollTop);

        if(!willDraw) {
          me._redraw();
        }
      };

      // Enforces the final vertical scroll position
      const setFinalVerticalPosition = () => {
        const finalVerticalScroll = getItemVerticalScroll(me, item);

        if (finalVerticalScroll.shouldScroll && finalVerticalScroll.itemTop != initialVerticalScroll.itemTop) {
          me._setScrollTop(-finalVerticalScroll.scrollOffset);
          me._redraw();
        }
      };

      // Perform one last check at the end to make sure the final vertical
      // position is correct
      const finalVerticalCallback = () => {
        // Double check we ended at the proper scroll position
        setFinalVerticalPosition();

        // Let the redraw settle and finalize the position.      
        setTimeout(setFinalVerticalPosition, 100);
      };

      // calculate the new middle and interval for the window
      const zoom = options && options.zoom !== undefined ? options.zoom : true;
      const middle = (start + end) / 2;
      const interval = zoom ? (end - start) * 1.1 : Math.max(this.range.end - this.range.start, (end - start) * 1.1);

      const animation = options && options.animation !== undefined ? options.animation : true;

      if (!animation) {
        // We aren't animating so set a default so that the final callback forces the vertical location
        initialVerticalScroll = { shouldScroll: false, scrollOffset: -1, itemTop: -1 };
      }

      this.range.setRange(middle - interval / 2, middle + interval / 2, { animation }, finalVerticalCallback, verticalAnimationFrame);  
    }
  }

  /**
   * Set Timeline window such that it fits all items
   * @param {Object} [options]  Available options:
   *                                `animation: boolean | {duration: number, easingFunction: string}`
   *                                    If true (default), the range is animated
   *                                    smoothly to the new window. An object can be
   *                                    provided to specify duration and easing function.
   *                                    Default duration is 500 ms, and default easing
   *                                    function is 'easeInOutQuad'.
   * @param {function} [callback]
   */
  fit(options, callback) {
    const animation = (options && options.animation !== undefined) ? options.animation : true;
    let range;

    if (this.itemsData.length === 1 && this.itemsData.get()[0].end === undefined) {
      // a single item -> don't fit, just show a range around the item from -4 to +3 days
      range = this.getDataRange();
      this.moveTo(range.min.valueOf(), {animation}, callback);
    }
    else {
      // exactly fit the items (plus a small margin)
      range = this.getItemRange();
      this.range.setRange(range.min, range.max, { animation }, callback);
    }
  }

  /**
   * Determine the range of the items, taking into account their actual width
   * and a margin of 10 pixels on both sides.
   *
   * @returns {{min: Date, max: Date}}
   */
  getItemRange() {
    // get a rough approximation for the range based on the items start and end dates
    const range = this.getDataRange();
    let min = range.min !== null ? range.min.valueOf() : null;
    let max = range.max !== null ? range.max.valueOf() : null;
    let minItem = null;
    let maxItem = null;

    if (min != null && max != null) {
      let interval = (max - min); // ms
      if (interval <= 0) {
        interval = 10;
      }
      const factor = interval / this.props.center.width;

      const redrawQueue = {};
      let redrawQueueLength = 0;

      // collect redraw functions
      util$3.forEach(this.itemSet.items, (item, key) => {
        if (item.groupShowing) {
          const returnQueue = true;
          redrawQueue[key] = item.redraw(returnQueue);
          redrawQueueLength = redrawQueue[key].length;
        }
      });

      const needRedraw = redrawQueueLength > 0;
      if (needRedraw) {
        // redraw all regular items
        for (let i = 0; i < redrawQueueLength; i++) {
          util$3.forEach(redrawQueue, fns => {
            fns[i]();
          });
        }
      }

       // calculate the date of the left side and right side of the items given
      util$3.forEach(this.itemSet.items, item => {
        const start = getStart(item);
        const end = getEnd(item);
        let startSide;
        let endSide;

        if (this.options.rtl) {
          startSide  = start - (item.getWidthRight()  + 10) * factor;
          endSide = end   + (item.getWidthLeft() + 10) * factor;
        } else {
          startSide  = start - (item.getWidthLeft()  + 10) * factor;
          endSide = end   + (item.getWidthRight() + 10) * factor;
        }

        if (startSide < min) {
          min = startSide;
          minItem = item;
        }
        if (endSide > max) {
          max = endSide;
          maxItem = item;
        }
      });

      if (minItem && maxItem) {
        const lhs = minItem.getWidthLeft() + 10;
        const rhs = maxItem.getWidthRight() + 10;
        const delta = this.props.center.width - lhs - rhs;  // px

        if (delta > 0) {
          if (this.options.rtl) {
            min = getStart(minItem) - rhs * interval / delta; // ms
            max = getEnd(maxItem)   + lhs * interval / delta; // ms
          } else {
            min = getStart(minItem) - lhs * interval / delta; // ms
            max = getEnd(maxItem)   + rhs * interval / delta; // ms
          }
        }
      }
    }

    return {
      min: min != null ? new Date(min) : null,
      max: max != null ? new Date(max) : null
    }
  }

  /**
   * Calculate the data range of the items start and end dates
   * @returns {{min: Date, max: Date}}
   */
  getDataRange() {
    let min = null;
    let max = null;

    if (this.itemsData) {
      this.itemsData.forEach(item => {
        const start = util$3.convert(item.start, 'Date').valueOf();
        const end   = util$3.convert(item.end != undefined ? item.end : item.start, 'Date').valueOf();
        if (min === null || start < min) {
          min = start;
        }
        if (max === null || end > max) {
          max = end;
        }
      });
    }

    return {
      min: min != null ? new Date(min) : null,
      max: max != null ? new Date(max) : null
    }
  }

  /**
   * Generate Timeline related information from an event
   * @param {Event} event
   * @return {Object} An object with related information, like on which area
   *                  The event happened, whether clicked on an item, etc.
   */
  getEventProperties(event) {
    const clientX = event.center ? event.center.x : event.clientX;
    const clientY = event.center ? event.center.y : event.clientY;
    const centerContainerRect = this.dom.centerContainer.getBoundingClientRect();
    const x = this.options.rtl ? centerContainerRect.right - clientX : clientX - centerContainerRect.left;
    const y = clientY - centerContainerRect.top;
    
    const item  = this.itemSet.itemFromTarget(event);
    const group = this.itemSet.groupFromTarget(event);
    const customTime = CustomTime.customTimeFromTarget(event);

    const snap = this.itemSet.options.snap || null;
    const scale = this.body.util.getScale();
    const step = this.body.util.getStep();
    const time = this._toTime(x);
    const snappedTime = snap ? snap(time, scale, step) : time;

    const element = util$3.getTarget(event);
    let what = null;
    if (item != null)                                                    {what = 'item';}
    else if (customTime != null)                                         {what = 'custom-time';}
    else if (util$3.hasParent(element, this.timeAxis.dom.foreground))      {what = 'axis';}
    else if (this.timeAxis2 && util$3.hasParent(element, this.timeAxis2.dom.foreground)) {what = 'axis';}
    else if (util$3.hasParent(element, this.itemSet.dom.labelSet))         {what = 'group-label';}
    else if (util$3.hasParent(element, this.currentTime.bar))              {what = 'current-time';}
    else if (util$3.hasParent(element, this.dom.center))                   {what = 'background';}

    return {
      event,
      item: item ? item.id : null,
      isCluster: item ? !!item.isCluster: false,
      items: item ? item.items || []: null,
      group: group ? group.groupId : null,
      customTime: customTime ? customTime.options.id : null,
      what,
      pageX: event.srcEvent ? event.srcEvent.pageX : event.pageX,
      pageY: event.srcEvent ? event.srcEvent.pageY : event.pageY,
      x,
      y,
      time,
      snappedTime
    }
  }

  /**
   * Toggle Timeline rolling mode
   */
  toggleRollingMode() {
    if (this.range.rolling) {
      this.range.stopRolling();
    } else {
      if (this.options.rollingMode == undefined) {
        this.setOptions(this.options);
      }
      this.range.startRolling();
    }
  }

  /**
   * redraw
   * @private
   */
  _redraw() {
    Core.prototype._redraw.call(this);
  }

  /**
   * on fit callback
   * @param {object} args
   * @private
   */
  _onFit(args) {
    const { start, end, animation } = args;
    if (!end) {
      this.moveTo(start.valueOf(), {
        animation
      });
    } else {
      this.range.setRange(start, end, {
        animation: animation
      });
    }
  }
}

/**
 *
 * @param {timeline.Item} item
 * @returns {number}
 */
function getStart(item) {
  return util$3.convert(item.data.start, 'Date').valueOf()
}

/**
 *
 * @param {timeline.Item} item
 * @returns {number}
 */
function getEnd(item) {
  const end = item.data.end != undefined ? item.data.end : item.data.start;
  return util$3.convert(end, 'Date').valueOf();
}

/**
 * @param {vis.Timeline} timeline
 * @param {timeline.Item} item
 * @return {{shouldScroll: bool, scrollOffset: number, itemTop: number}}
 */
function getItemVerticalScroll(timeline, item) {
  if (!item.parent) {
    // The item no longer exists, so ignore this focus.
    return false;
  }

  const itemsetHeight = timeline.options.rtl ? timeline.props.rightContainer.height : timeline.props.leftContainer.height;
  const contentHeight = timeline.props.center.height;
  
  const group = item.parent;
  let offset = group.top;
  let shouldScroll = true;
  const orientation = timeline.timeAxis.options.orientation.axis;
  
  const itemTop = () => {
  if (orientation == "bottom") {
      return group.height - item.top - item.height;
    }
    else {
      return item.top;
    }
  };

  const currentScrollHeight = timeline._getScrollTop() * -1;
  const targetOffset = offset + itemTop();
  const height = item.height;

  if (targetOffset < currentScrollHeight) {
    if (offset + itemsetHeight <= offset + itemTop() + height) {
      offset += itemTop() - timeline.itemSet.options.margin.item.vertical;
    }
  }
  else if (targetOffset + height > currentScrollHeight + itemsetHeight) {
    offset += itemTop() + height - itemsetHeight + timeline.itemSet.options.margin.item.vertical;
  }
  else {
    shouldScroll = false;
  }

  offset = Math.min(offset, contentHeight - itemsetHeight);

  return { shouldScroll, scrollOffset: offset, itemTop: targetOffset };
}

// DOM utility methods

/**
 * this prepares the JSON container for allocating SVG elements
 * @param {Object} JSONcontainer
 * @private
 */
function prepareElements(JSONcontainer) {
  // cleanup the redundant svgElements;
  for (var elementType in JSONcontainer) {
    if (JSONcontainer.hasOwnProperty(elementType)) {
      JSONcontainer[elementType].redundant = JSONcontainer[elementType].used;
      JSONcontainer[elementType].used = [];
    }
  }
}

/**
 * this cleans up all the unused SVG elements. By asking for the parentNode, we only need to supply the JSON container from
 * which to remove the redundant elements.
 *
 * @param {Object} JSONcontainer
 * @private
 */
function cleanupElements(JSONcontainer) {
  // cleanup the redundant svgElements;
  for (var elementType in JSONcontainer) {
    if (JSONcontainer.hasOwnProperty(elementType)) {
      if (JSONcontainer[elementType].redundant) {
        for (var i = 0; i < JSONcontainer[elementType].redundant.length; i++) {
          JSONcontainer[elementType].redundant[i].parentNode.removeChild(JSONcontainer[elementType].redundant[i]);
        }
        JSONcontainer[elementType].redundant = [];
      }
    }
  }
}

/**
 * Ensures that all elements are removed first up so they can be recreated cleanly
 * @param {Object} JSONcontainer
 */
function resetElements(JSONcontainer) {
  prepareElements(JSONcontainer);
  cleanupElements(JSONcontainer);
  prepareElements(JSONcontainer);
}

/**
 * Allocate or generate an SVG element if needed. Store a reference to it in the JSON container and draw it in the svgContainer
 * the JSON container and the SVG container have to be supplied so other svg containers (like the legend) can use this.
 *
 * @param {string} elementType
 * @param {Object} JSONcontainer
 * @param {Object} svgContainer
 * @returns {Element}
 * @private
 */
function getSVGElement(elementType, JSONcontainer, svgContainer) {
  var element;
  // allocate SVG element, if it doesnt yet exist, create one.
  if (JSONcontainer.hasOwnProperty(elementType)) { // this element has been created before
    // check if there is an redundant element
    if (JSONcontainer[elementType].redundant.length > 0) {
      element = JSONcontainer[elementType].redundant[0];
      JSONcontainer[elementType].redundant.shift();
    }
    else {
      // create a new element and add it to the SVG
      element = document.createElementNS('http://www.w3.org/2000/svg', elementType);
      svgContainer.appendChild(element);
    }
  }
  else {
    // create a new element and add it to the SVG, also create a new object in the svgElements to keep track of it.
    element = document.createElementNS('http://www.w3.org/2000/svg', elementType);
    JSONcontainer[elementType] = {used: [], redundant: []};
    svgContainer.appendChild(element);
  }
  JSONcontainer[elementType].used.push(element);
  return element;
}


/**
 * Allocate or generate an SVG element if needed. Store a reference to it in the JSON container and draw it in the svgContainer
 * the JSON container and the SVG container have to be supplied so other svg containers (like the legend) can use this.
 *
 * @param {string} elementType
 * @param {Object} JSONcontainer
 * @param {Element} DOMContainer
 * @param {Element} insertBefore
 * @returns {*}
 */
function getDOMElement(elementType, JSONcontainer, DOMContainer, insertBefore) {
  var element;
  // allocate DOM element, if it doesnt yet exist, create one.
  if (JSONcontainer.hasOwnProperty(elementType)) { // this element has been created before
    // check if there is an redundant element
    if (JSONcontainer[elementType].redundant.length > 0) {
      element = JSONcontainer[elementType].redundant[0];
      JSONcontainer[elementType].redundant.shift();
    }
    else {
      // create a new element and add it to the SVG
      element = document.createElement(elementType);
      if (insertBefore !== undefined) {
        DOMContainer.insertBefore(element, insertBefore);
      }
      else {
        DOMContainer.appendChild(element);
      }
    }
  }
  else {
    // create a new element and add it to the SVG, also create a new object in the svgElements to keep track of it.
    element = document.createElement(elementType);
    JSONcontainer[elementType] = {used: [], redundant: []};
    if (insertBefore !== undefined) {
      DOMContainer.insertBefore(element, insertBefore);
    }
    else {
      DOMContainer.appendChild(element);
    }
  }
  JSONcontainer[elementType].used.push(element);
  return element;
}




/**
 * Draw a point object. This is a separate function because it can also be called by the legend.
 * The reason the JSONcontainer and the target SVG svgContainer have to be supplied is so the legend can use these functions
 * as well.
 *
 * @param {number} x
 * @param {number} y
 * @param {Object} groupTemplate: A template containing the necessary information to draw the datapoint e.g., {style: 'circle', size: 5, className: 'className' }
 * @param {Object} JSONcontainer
 * @param {Object} svgContainer
 * @param {Object} labelObj
 * @returns {vis.PointItem}
 */
function drawPoint(x, y, groupTemplate, JSONcontainer, svgContainer, labelObj) {
  var point;
  if (groupTemplate.style == 'circle') {
    point = getSVGElement('circle', JSONcontainer, svgContainer);
    point.setAttributeNS(null, "cx", x);
    point.setAttributeNS(null, "cy", y);
    point.setAttributeNS(null, "r", 0.5 * groupTemplate.size);
  }
  else {
    point = getSVGElement('rect', JSONcontainer, svgContainer);
    point.setAttributeNS(null, "x", x - 0.5 * groupTemplate.size);
    point.setAttributeNS(null, "y", y - 0.5 * groupTemplate.size);
    point.setAttributeNS(null, "width", groupTemplate.size);
    point.setAttributeNS(null, "height", groupTemplate.size);
  }

  if (groupTemplate.styles !== undefined) {
    point.setAttributeNS(null, "style", groupTemplate.styles);
  }
  point.setAttributeNS(null, "class", groupTemplate.className + " vis-point");
  //handle label


  if (labelObj) {
    var label = getSVGElement('text', JSONcontainer, svgContainer);
    if (labelObj.xOffset) {
      x = x + labelObj.xOffset;
    }

    if (labelObj.yOffset) {
      y = y + labelObj.yOffset;
    }
    if (labelObj.content) {
      label.textContent = labelObj.content;
    }

    if (labelObj.className) {
      label.setAttributeNS(null, "class", labelObj.className  + " vis-label");
    }
    label.setAttributeNS(null, "x", x);
    label.setAttributeNS(null, "y", y);
  }

  return point;
}

/**
 * draw a bar SVG element centered on the X coordinate
 *
 * @param {number} x
 * @param {number} y
 * @param {number} width
 * @param {number} height
 * @param {string} className
 * @param {Object} JSONcontainer
 * @param {Object} svgContainer
 * @param {string} style
 */
function drawBar (x, y, width, height, className, JSONcontainer, svgContainer, style) {
  if (height != 0) {
    if (height < 0) {
      height *= -1;
      y -= height;
    }
    var rect = getSVGElement('rect',JSONcontainer, svgContainer);
    rect.setAttributeNS(null, "x", x - 0.5 * width);
    rect.setAttributeNS(null, "y", y);
    rect.setAttributeNS(null, "width", width);
    rect.setAttributeNS(null, "height", height);
    rect.setAttributeNS(null, "class", className);
    if (style) {
      rect.setAttributeNS(null, "style", style);
    }
  }
}

/**
 * get default language
 * @returns {string}
 */
function getNavigatorLanguage() {
  try {
    if (!navigator) return 'en';
    if (navigator.languages && navigator.languages.length) {
      return navigator.languages;
    } else {
      return navigator.userLanguage || navigator.language || navigator.browserLanguage || 'en';
    }
  } 
  catch(error) {
    return 'en';
  }
}

/** DataScale */
class DataScale {
  /**
   *
   * @param {number} start
   * @param {number} end
   * @param {boolean} autoScaleStart
   * @param {boolean} autoScaleEnd
   * @param {number} containerHeight
   * @param {number} majorCharHeight
   * @param {boolean} zeroAlign
   * @param {function} formattingFunction
   * @constructor DataScale
   */
  constructor(
    start,
    end,
    autoScaleStart,
    autoScaleEnd,
    containerHeight,
    majorCharHeight,
    zeroAlign = false,
    formattingFunction=false) {
    this.majorSteps = [1, 2, 5, 10];
    this.minorSteps = [0.25, 0.5, 1, 2];
    this.customLines = null;

    this.containerHeight = containerHeight;
    this.majorCharHeight = majorCharHeight;
    this._start = start;
    this._end = end;

    this.scale = 1;
    this.minorStepIdx = -1;
    this.magnitudefactor = 1;
    this.determineScale();

    this.zeroAlign = zeroAlign;
    this.autoScaleStart = autoScaleStart;
    this.autoScaleEnd = autoScaleEnd;

    this.formattingFunction = formattingFunction;

    if (autoScaleStart || autoScaleEnd) {
      const me = this;
      const roundToMinor = value => {
        const rounded = value - (value % (me.magnitudefactor * me.minorSteps[me.minorStepIdx]));
        if (value % (me.magnitudefactor * me.minorSteps[me.minorStepIdx]) > 0.5 * (me.magnitudefactor * me.minorSteps[me.minorStepIdx])) {
          return rounded + (me.magnitudefactor * me.minorSteps[me.minorStepIdx]);
        }
        else {
          return rounded;
        }
      };
      if (autoScaleStart) {
        this._start -= this.magnitudefactor * 2 * this.minorSteps[this.minorStepIdx];
        this._start = roundToMinor(this._start);
      }

      if (autoScaleEnd) {
        this._end += this.magnitudefactor * this.minorSteps[this.minorStepIdx];
        this._end = roundToMinor(this._end);
      }
      this.determineScale();
    }
  }

  /**
   * set chart height
   * @param {number} majorCharHeight 
   */
  setCharHeight(majorCharHeight) {
    this.majorCharHeight = majorCharHeight;
  }

  /**
   * set height
   * @param {number} containerHeight 
   */
  setHeight(containerHeight) {
    this.containerHeight = containerHeight;
  }

  /**
   * determine scale
   */
  determineScale() {
    const range = this._end - this._start;
    this.scale = this.containerHeight / range;
    const minimumStepValue = this.majorCharHeight / this.scale;
    const orderOfMagnitude = (range > 0)
        ? Math.round(Math.log(range) / Math.LN10)
        : 0;

    this.minorStepIdx = -1;
    this.magnitudefactor = Math.pow(10, orderOfMagnitude);

    let start = 0;
    if (orderOfMagnitude < 0) {
      start = orderOfMagnitude;
    }

    let solutionFound = false;
    for (let l = start; Math.abs(l) <= Math.abs(orderOfMagnitude); l++) {
      this.magnitudefactor = Math.pow(10, l);
      for (let j = 0; j < this.minorSteps.length; j++) {
        const stepSize = this.magnitudefactor * this.minorSteps[j];
        if (stepSize >= minimumStepValue) {
          solutionFound = true;
          this.minorStepIdx = j;
          break;
        }
      }
      if (solutionFound === true) {
        break;
      }
    }
  }

  /**
   * returns if value is major
   * @param {number} value
   * @returns {boolean} 
   */
  is_major(value) {
    return (value % (this.magnitudefactor * this.majorSteps[this.minorStepIdx]) === 0);
  }

  /**
   * returns step size
   * @returns {number} 
   */
  getStep() {
    return this.magnitudefactor * this.minorSteps[this.minorStepIdx];
  }

  /**
   * returns first major
   * @returns {number} 
   */
  getFirstMajor() {
    const majorStep = this.magnitudefactor * this.majorSteps[this.minorStepIdx];
    return this.convertValue(this._start + ((majorStep - (this._start % majorStep)) % majorStep));
  }

  /**
   * returns first major
   * @param {date} current
   * @returns {date} formatted date
   */
  formatValue(current) {
    let returnValue = current.toPrecision(5);
    if (typeof this.formattingFunction === 'function') {
      returnValue = this.formattingFunction(current);
    }

    if (typeof returnValue === 'number') {
      return `${returnValue}`;
    }
    else if (typeof returnValue === 'string') {
      return returnValue;
    }
    else {
      return current.toPrecision(5);
    }

  }

  /**
   * returns lines
   * @returns {object} lines
   */
  getLines() {
    const lines = [];
    const step = this.getStep();
    const bottomOffset = (step - (this._start % step)) % step;
    for (let i = (this._start + bottomOffset); this._end-i > 0.00001; i += step) {
      if (i != this._start) { //Skip the bottom line
        lines.push({major: this.is_major(i), y: this.convertValue(i), val: this.formatValue(i)});
      }
    }
    return lines;
  }

  /**
   * follow scale
   * @param {object} other
   */
  followScale(other) {
    const oldStepIdx = this.minorStepIdx;
    const oldStart = this._start;
    const oldEnd = this._end;

    const me = this;
    const increaseMagnitude = () => {
      me.magnitudefactor *= 2;
    };
    const decreaseMagnitude = () => {
      me.magnitudefactor /= 2;
    };

    if ((other.minorStepIdx <= 1 && this.minorStepIdx <= 1) || (other.minorStepIdx > 1 && this.minorStepIdx > 1)) ; else if (other.minorStepIdx < this.minorStepIdx) {
      //I'm 5, they are 4 per major.
      this.minorStepIdx = 1;
      if (oldStepIdx == 2) {
        increaseMagnitude();
      } else {
        increaseMagnitude();
        increaseMagnitude();
      }
    } else {
      //I'm 4, they are 5 per major
      this.minorStepIdx = 2;
      if (oldStepIdx == 1) {
        decreaseMagnitude();
      } else {
        decreaseMagnitude();
        decreaseMagnitude();
      }
    }

    //Get masters stats:
    const otherZero = other.convertValue(0);
    const otherStep = other.getStep() * other.scale;

    let done = false;
    let count = 0;
    //Loop until magnitude is correct for given constrains.
    while (!done && count++ <5) {

      //Get my stats:
      this.scale = otherStep / (this.minorSteps[this.minorStepIdx] * this.magnitudefactor);
      const newRange = this.containerHeight / this.scale;

      //For the case the magnitudefactor has changed:
      this._start = oldStart;
      this._end = this._start + newRange;

      const myOriginalZero = this._end * this.scale;
      const majorStep = this.magnitudefactor * this.majorSteps[this.minorStepIdx];
      const majorOffset = this.getFirstMajor() - other.getFirstMajor();

      if (this.zeroAlign) {
        const zeroOffset = otherZero - myOriginalZero;
        this._end += (zeroOffset / this.scale);
        this._start = this._end - newRange;
      } else {
        if (!this.autoScaleStart) {
          this._start += majorStep - (majorOffset / this.scale);
          this._end = this._start + newRange;
        } else {
          this._start -= majorOffset / this.scale;
          this._end = this._start + newRange;
        }
      }
      if (!this.autoScaleEnd && this._end > oldEnd+0.00001) {
        //Need to decrease magnitude to prevent scale overshoot! (end)
        decreaseMagnitude();
        done = false;
        continue;
      }
      if (!this.autoScaleStart && this._start < oldStart-0.00001) {
        if (this.zeroAlign && oldStart >= 0) {
          console.warn("Can't adhere to given 'min' range, due to zeroalign");
        } else {
          //Need to decrease magnitude to prevent scale overshoot! (start)
          decreaseMagnitude();
          done = false;
          continue;
        }
      }
      if (this.autoScaleStart && this.autoScaleEnd && newRange < (oldEnd-oldStart)){
        increaseMagnitude();
        done = false;
        continue;
      }
      done = true;
    }
  }

  /**
   * convert value
   * @param {number} value
   * @returns {number} 
   */
  convertValue(value) {
    return this.containerHeight - ((value - this._start) * this.scale);
  }

  /**
   * returns screen to value
   * @param {number} pixels
   * @returns {number} 
   */
  screenToValue(pixels) {
    return ((this.containerHeight - pixels) / this.scale) + this._start;
  }
}

/** A horizontal time axis */
class DataAxis extends Component {
  /**
 * @param {Object} body
 * @param {Object} [options]        See DataAxis.setOptions for the available
 *                                  options.
 * @param {SVGElement} svg
 * @param {timeline.LineGraph.options} linegraphOptions
 * @constructor DataAxis
 * @extends Component
 */
  constructor(body, options, svg, linegraphOptions) {
    super();
    this.id = dist.v4();
    this.body = body;

    this.defaultOptions = {
      orientation: 'left',  // supported: 'left', 'right'
      showMinorLabels: true,
      showMajorLabels: true,
      showWeekScale: false,
      icons: false,
      majorLinesOffset: 7,
      minorLinesOffset: 4,
      labelOffsetX: 10,
      labelOffsetY: 2,
      iconWidth: 20,
      width: '40px',
      visible: true,
      alignZeros: true,
      left: {
        range: {min: undefined, max: undefined},
        format(value) {
          return `${parseFloat(value.toPrecision(3))}`;
        },
        title: {text: undefined, style: undefined}
      },
      right: {
        range: {min: undefined, max: undefined},
        format(value) {
          return `${parseFloat(value.toPrecision(3))}`;
        },
        title: {text: undefined, style: undefined}
      }
    };

    this.linegraphOptions = linegraphOptions;
    this.linegraphSVG = svg;
    this.props = {};
    this.DOMelements = { // dynamic elements
      lines: {},
      labels: {},
      title: {}
    };

    this.dom = {};
    this.scale = undefined;
    this.range = {start: 0, end: 0};

    this.options = util$3.extend({}, this.defaultOptions);
    this.conversionFactor = 1;

    this.setOptions(options);
    this.width = Number((`${this.options.width}`).replace("px", ""));
    this.minWidth = this.width;
    this.height = this.linegraphSVG.getBoundingClientRect().height;
    this.hidden = false;

    this.stepPixels = 25;
    this.zeroCrossing = -1;
    this.amountOfSteps = -1;

    this.lineOffset = 0;
    this.master = true;
    this.masterAxis = null;
    this.svgElements = {};
    this.iconsRemoved = false;

    this.groups = {};
    this.amountOfGroups = 0;

    // create the HTML DOM
    this._create();
    if (this.scale == undefined) {
      this._redrawLabels();
    }
    this.framework = {svg: this.svg, svgElements: this.svgElements, options: this.options, groups: this.groups};

    const me = this;
    this.body.emitter.on("verticalDrag", () => {
      me.dom.lineContainer.style.top = `${me.body.domProps.scrollTop}px`;
    });
  }

  /**
   * Adds group to data axis
   * @param {string} label 
   * @param {object} graphOptions
   */
  addGroup(label, graphOptions) {
    if (!this.groups.hasOwnProperty(label)) {
      this.groups[label] = graphOptions;
    }
    this.amountOfGroups += 1;
  }

  /**
   * updates group of data axis
   * @param {string} label 
   * @param {object} graphOptions
   */
  updateGroup(label, graphOptions) {
    if (!this.groups.hasOwnProperty(label)) {
      this.amountOfGroups += 1;
    }
    this.groups[label] = graphOptions;
  }

  /**
   * removes group of data axis
   * @param {string} label 
   */
  removeGroup(label) {
    if (this.groups.hasOwnProperty(label)) {
      delete this.groups[label];
      this.amountOfGroups -= 1;
    }
  }

  /**
   * sets options
   * @param {object} options
   */
  setOptions(options) {
    if (options) {
      let redraw = false;
      if (this.options.orientation != options.orientation && options.orientation !== undefined) {
        redraw = true;
      }
      const fields = [
        'orientation',
        'showMinorLabels',
        'showMajorLabels',
        'icons',
        'majorLinesOffset',
        'minorLinesOffset',
        'labelOffsetX',
        'labelOffsetY',
        'iconWidth',
        'width',
        'visible',
        'left',
        'right',
        'alignZeros'
      ];
      util$3.selectiveDeepExtend(fields, this.options, options);

      this.minWidth = Number((`${this.options.width}`).replace("px", ""));
      if (redraw === true && this.dom.frame) {
        this.hide();
        this.show();
      }
    }
  }

  /**
   * Create the HTML DOM for the DataAxis
   */
  _create() {
    this.dom.frame = document.createElement('div');
    this.dom.frame.style.width = this.options.width;
    this.dom.frame.style.height = this.height;

    this.dom.lineContainer = document.createElement('div');
    this.dom.lineContainer.style.width = '100%';
    this.dom.lineContainer.style.height = this.height;
    this.dom.lineContainer.style.position = 'relative';
    this.dom.lineContainer.style.visibility = 'visible';
    this.dom.lineContainer.style.display = 'block';

    // create svg element for graph drawing.
    this.svg = document.createElementNS('http://www.w3.org/2000/svg', "svg");
    this.svg.style.position = "absolute";
    this.svg.style.top = '0px';
    this.svg.style.height = '100%';
    this.svg.style.width = '100%';
    this.svg.style.display = "block";
    this.dom.frame.appendChild(this.svg);
  }

  /**
   * redraws groups icons
   */
  _redrawGroupIcons() {
    prepareElements(this.svgElements);

    let x;
    const iconWidth = this.options.iconWidth;
    const iconHeight = 15;
    const iconOffset = 4;
    let y = iconOffset + 0.5 * iconHeight;

    if (this.options.orientation === 'left') {
      x = iconOffset;
    }
    else {
      x = this.width - iconWidth - iconOffset;
    }

    const groupArray = Object.keys(this.groups);
    groupArray.sort((a, b) => a < b ? -1 : 1);

    for (const groupId of groupArray) {
      if (this.groups[groupId].visible === true && (this.linegraphOptions.visibility[groupId] === undefined || this.linegraphOptions.visibility[groupId] === true)) {
        this.groups[groupId].getLegend(iconWidth, iconHeight, this.framework, x, y);
        y += iconHeight + iconOffset;
      }
    }

    cleanupElements(this.svgElements);
    this.iconsRemoved = false;
  }

  /**
   * Cleans up icons
   */
  _cleanupIcons() {
    if (this.iconsRemoved === false) {
      prepareElements(this.svgElements);
      cleanupElements(this.svgElements);
      this.iconsRemoved = true;
    }
  }

  /**
   * Create the HTML DOM for the DataAxis
   */
  show() {
    this.hidden = false;
    if (!this.dom.frame.parentNode) {
      if (this.options.orientation === 'left') {
        this.body.dom.left.appendChild(this.dom.frame);
      }
      else {
        this.body.dom.right.appendChild(this.dom.frame);
      }
    }

    if (!this.dom.lineContainer.parentNode) {
      this.body.dom.backgroundHorizontal.appendChild(this.dom.lineContainer);
    }
    this.dom.lineContainer.style.display = 'block';
  }

  /**
   * Create the HTML DOM for the DataAxis
   */
  hide() {
    this.hidden = true;
    if (this.dom.frame.parentNode) {
      this.dom.frame.parentNode.removeChild(this.dom.frame);
    }

    this.dom.lineContainer.style.display = 'none';
  }

  /**
   * Set a range (start and end)
   * @param {number} start
   * @param {number} end
   */
  setRange(start, end) {
    this.range.start = start;
    this.range.end = end;
  }

  /**
   * Repaint the component
   * @return {boolean} Returns true if the component is resized
   */
  redraw() {
    let resized = false;
    let activeGroups = 0;

    // Make sure the line container adheres to the vertical scrolling.
    this.dom.lineContainer.style.top = `${this.body.domProps.scrollTop}px`;

    for (const groupId in this.groups) {
      if (this.groups.hasOwnProperty(groupId)) {
        if (this.groups[groupId].visible === true && (this.linegraphOptions.visibility[groupId] === undefined || this.linegraphOptions.visibility[groupId] === true)) {
          activeGroups++;
        }
      }
    }
    if (this.amountOfGroups === 0 || activeGroups === 0) {
      this.hide();
    }
    else {
      this.show();
      this.height = Number(this.linegraphSVG.style.height.replace("px", ""));

      // svg offsetheight did not work in firefox and explorer...
      this.dom.lineContainer.style.height = `${this.height}px`;
      this.width = this.options.visible === true ? Number((`${this.options.width}`).replace("px", "")) : 0;

      const props = this.props;
      const frame = this.dom.frame;

      // update classname
      frame.className = 'vis-data-axis';

      // calculate character width and height
      this._calculateCharSize();

      const orientation = this.options.orientation;
      const showMinorLabels = this.options.showMinorLabels;
      const showMajorLabels = this.options.showMajorLabels;

      const backgroundHorizontalOffsetWidth = this.body.dom.backgroundHorizontal.offsetWidth;

      // determine the width and height of the elements for the axis
      props.minorLabelHeight = showMinorLabels ? props.minorCharHeight : 0;
      props.majorLabelHeight = showMajorLabels ? props.majorCharHeight : 0;

      props.minorLineWidth = backgroundHorizontalOffsetWidth - this.lineOffset - this.width + 2 * this.options.minorLinesOffset;
      props.minorLineHeight = 1;
      props.majorLineWidth = backgroundHorizontalOffsetWidth - this.lineOffset - this.width + 2 * this.options.majorLinesOffset;
      props.majorLineHeight = 1;

      //  take frame offline while updating (is almost twice as fast)
      if (orientation === 'left') {
        frame.style.top = '0';
        frame.style.left = '0';
        frame.style.bottom = '';
        frame.style.width = `${this.width}px`;
        frame.style.height = `${this.height}px`;
        this.props.width = this.body.domProps.left.width;
        this.props.height = this.body.domProps.left.height;
      }
      else { // right
        frame.style.top = '';
        frame.style.bottom = '0';
        frame.style.left = '0';
        frame.style.width = `${this.width}px`;
        frame.style.height = `${this.height}px`;
        this.props.width = this.body.domProps.right.width;
        this.props.height = this.body.domProps.right.height;
      }

      resized = this._redrawLabels();
      resized = this._isResized() || resized;

      if (this.options.icons === true) {
        this._redrawGroupIcons();
      }
      else {
        this._cleanupIcons();
      }

      this._redrawTitle(orientation);
    }
    return resized;
  }

  /**
   * Repaint major and minor text labels and vertical grid lines
   *
   * @returns {boolean}
   * @private
   */
  _redrawLabels() {
    let resized = false;
    prepareElements(this.DOMelements.lines);
    prepareElements(this.DOMelements.labels);
    const orientation = this.options['orientation'];
    const customRange = this.options[orientation].range != undefined ? this.options[orientation].range : {};

    //Override range with manual options:
    let autoScaleEnd = true;
    if (customRange.max != undefined) {
      this.range.end = customRange.max;
      autoScaleEnd = false;
    }
    let autoScaleStart = true;
    if (customRange.min != undefined) {
      this.range.start = customRange.min;
      autoScaleStart = false;
    }

    this.scale = new DataScale(
      this.range.start,
      this.range.end,
      autoScaleStart,
      autoScaleEnd,
      this.dom.frame.offsetHeight,
      this.props.majorCharHeight,
      this.options.alignZeros,
      this.options[orientation].format
    );

    if (this.master === false && this.masterAxis != undefined) {
      this.scale.followScale(this.masterAxis.scale);
      this.dom.lineContainer.style.display = 'none';
    } else {
      this.dom.lineContainer.style.display = 'block';
    }

    //Is updated in side-effect of _redrawLabel():
    this.maxLabelSize = 0;

    const lines = this.scale.getLines();
    lines.forEach(
      line=> {
        const y = line.y;
        const isMajor = line.major;
        if (this.options['showMinorLabels'] && isMajor === false) {
          this._redrawLabel(y - 2, line.val, orientation, 'vis-y-axis vis-minor', this.props.minorCharHeight);
        }
        if (isMajor) {
          if (y >= 0) {
            this._redrawLabel(y - 2, line.val, orientation, 'vis-y-axis vis-major', this.props.majorCharHeight);
          }
        }
        if (this.master === true) {
          if (isMajor) {
            this._redrawLine(y, orientation, 'vis-grid vis-horizontal vis-major', this.options.majorLinesOffset, this.props.majorLineWidth);
          }
          else {
            this._redrawLine(y, orientation, 'vis-grid vis-horizontal vis-minor', this.options.minorLinesOffset, this.props.minorLineWidth);
          }
        }
      });

    // Note that title is rotated, so we're using the height, not width!
    let titleWidth = 0;
    if (this.options[orientation].title !== undefined && this.options[orientation].title.text !== undefined) {
      titleWidth = this.props.titleCharHeight;
    }
    const offset = this.options.icons === true ? Math.max(this.options.iconWidth, titleWidth) + this.options.labelOffsetX + 15 : titleWidth + this.options.labelOffsetX + 15;

    // this will resize the yAxis to accommodate the labels.
    if (this.maxLabelSize > (this.width - offset) && this.options.visible === true) {
      this.width = this.maxLabelSize + offset;
      this.options.width = `${this.width}px`;
      cleanupElements(this.DOMelements.lines);
      cleanupElements(this.DOMelements.labels);
      this.redraw();
      resized = true;
    }
    // this will resize the yAxis if it is too big for the labels.
    else if (this.maxLabelSize < (this.width - offset) && this.options.visible === true && this.width > this.minWidth) {
      this.width = Math.max(this.minWidth, this.maxLabelSize + offset);
      this.options.width = `${this.width}px`;
      cleanupElements(this.DOMelements.lines);
      cleanupElements(this.DOMelements.labels);
      this.redraw();
      resized = true;
    }
    else {
      cleanupElements(this.DOMelements.lines);
      cleanupElements(this.DOMelements.labels);
      resized = false;
    }

    return resized;
  }

  /**
   * converts value
   * @param {number} value
   * @returns {number} converted number
   */
  convertValue(value) {
    return this.scale.convertValue(value);
  }

  /**
   * converts value
   * @param {number} x
   * @returns {number} screen value
   */
  screenToValue(x) {
    return this.scale.screenToValue(x);
  }

  /**
   * Create a label for the axis at position x
   *
   * @param {number} y
   * @param {string} text
   * @param {'top'|'right'|'bottom'|'left'} orientation
   * @param {string} className
   * @param {number} characterHeight
   * @private
   */
  _redrawLabel(y, text, orientation, className, characterHeight) {
    // reuse redundant label
    const label = getDOMElement('div', this.DOMelements.labels, this.dom.frame); //this.dom.redundant.labels.shift();
    label.className = className;
    label.innerHTML = util$3.xss(text);
    if (orientation === 'left') {
      label.style.left = `-${this.options.labelOffsetX}px`;
      label.style.textAlign = "right";
    }
    else {
      label.style.right = `-${this.options.labelOffsetX}px`;
      label.style.textAlign = "left";
    }

    label.style.top = `${y - 0.5 * characterHeight + this.options.labelOffsetY}px`;

    text += '';

    const largestWidth = Math.max(this.props.majorCharWidth, this.props.minorCharWidth);
    if (this.maxLabelSize < text.length * largestWidth) {
      this.maxLabelSize = text.length * largestWidth;
    }
  }

  /**
   * Create a minor line for the axis at position y
   * @param {number} y
   * @param {'top'|'right'|'bottom'|'left'} orientation
   * @param {string} className
   * @param {number} offset
   * @param {number} width
   */
  _redrawLine(y, orientation, className, offset, width) {
    if (this.master === true) {
      const line = getDOMElement('div', this.DOMelements.lines, this.dom.lineContainer);  //this.dom.redundant.lines.shift();
      line.className = className;
      line.innerHTML = '';

      if (orientation === 'left') {
        line.style.left = `${this.width - offset}px`;
      }
      else {
        line.style.right = `${this.width - offset}px`;
      }

      line.style.width = `${width}px`;
      line.style.top = `${y}px`;
    }
  }

  /**
   * Create a title for the axis
   * @private
   * @param {'top'|'right'|'bottom'|'left'} orientation
   */
  _redrawTitle(orientation) {
    prepareElements(this.DOMelements.title);

    // Check if the title is defined for this axes
    if (this.options[orientation].title !== undefined && this.options[orientation].title.text !== undefined) {
      const title = getDOMElement('div', this.DOMelements.title, this.dom.frame);
      title.className = `vis-y-axis vis-title vis-${orientation}`;
      title.innerHTML = util$3.xss(this.options[orientation].title.text);

      // Add style - if provided
      if (this.options[orientation].title.style !== undefined) {
        util$3.addCssText(title, this.options[orientation].title.style);
      }

      if (orientation === 'left') {
        title.style.left = `${this.props.titleCharHeight}px`;
      }
      else {
        title.style.right = `${this.props.titleCharHeight}px`;
      }

      title.style.width = `${this.height}px`;
    }

    // we need to clean up in case we did not use all elements.
    cleanupElements(this.DOMelements.title);
  }

  /**
   * Determine the size of text on the axis (both major and minor axis).
   * The size is calculated only once and then cached in this.props.
   * @private
   */
  _calculateCharSize() {
    // determine the char width and height on the minor axis
    if (!('minorCharHeight' in this.props)) {
      const textMinor = document.createTextNode('0');
      const measureCharMinor = document.createElement('div');
      measureCharMinor.className = 'vis-y-axis vis-minor vis-measure';
      measureCharMinor.appendChild(textMinor);
      this.dom.frame.appendChild(measureCharMinor);

      this.props.minorCharHeight = measureCharMinor.clientHeight;
      this.props.minorCharWidth = measureCharMinor.clientWidth;

      this.dom.frame.removeChild(measureCharMinor);
    }

    if (!('majorCharHeight' in this.props)) {
      const textMajor = document.createTextNode('0');
      const measureCharMajor = document.createElement('div');
      measureCharMajor.className = 'vis-y-axis vis-major vis-measure';
      measureCharMajor.appendChild(textMajor);
      this.dom.frame.appendChild(measureCharMajor);

      this.props.majorCharHeight = measureCharMajor.clientHeight;
      this.props.majorCharWidth = measureCharMajor.clientWidth;

      this.dom.frame.removeChild(measureCharMajor);
    }

    if (!('titleCharHeight' in this.props)) {
      const textTitle = document.createTextNode('0');
      const measureCharTitle = document.createElement('div');
      measureCharTitle.className = 'vis-y-axis vis-title vis-measure';
      measureCharTitle.appendChild(textTitle);
      this.dom.frame.appendChild(measureCharTitle);

      this.props.titleCharHeight = measureCharTitle.clientHeight;
      this.props.titleCharWidth = measureCharTitle.clientWidth;

      this.dom.frame.removeChild(measureCharTitle);
    }
  }
}

/**
 *
 * @param {number | string} groupId
 * @param {Object} options   // TODO: Describe options
 *
 * @constructor Points
 */
function Points(groupId, options) {  // eslint-disable-line no-unused-vars
}

/**
 * draw the data points
 *
 * @param {Array} dataset
 * @param {GraphGroup} group
 * @param {Object} framework            | SVG DOM element
 * @param {number} [offset]
 */
Points.draw = function (dataset, group, framework, offset) {
  offset = offset || 0;
  var callback = getCallback(framework, group);

  for (var i = 0; i < dataset.length; i++) {
    if (!callback) {
      // draw the point the simple way.
      drawPoint(dataset[i].screen_x + offset, dataset[i].screen_y, getGroupTemplate(group), framework.svgElements, framework.svg, dataset[i].label);
    }
    else {
      var callbackResult = callback(dataset[i], group); // result might be true, false or an object
      if (callbackResult === true || typeof callbackResult === 'object') {
        drawPoint(dataset[i].screen_x + offset, dataset[i].screen_y, getGroupTemplate(group, callbackResult), framework.svgElements, framework.svg, dataset[i].label);
      }
    }
  }
};

Points.drawIcon = function (group, x, y, iconWidth, iconHeight, framework) {
  var fillHeight = iconHeight * 0.5;

  var outline = getSVGElement("rect", framework.svgElements, framework.svg);
  outline.setAttributeNS(null, "x", x);
  outline.setAttributeNS(null, "y", y - fillHeight);
  outline.setAttributeNS(null, "width", iconWidth);
  outline.setAttributeNS(null, "height", 2 * fillHeight);
  outline.setAttributeNS(null, "class", "vis-outline");

  //Don't call callback on icon
  drawPoint(x + 0.5 * iconWidth, y, getGroupTemplate(group), framework.svgElements, framework.svg);
};

/**
 *
 * @param {vis.Group} group
 * @param {any} callbackResult
 * @returns {{style: *, styles: (*|string), size: *, className: *}}
 */
function getGroupTemplate(group, callbackResult) {
  callbackResult = (typeof callbackResult === 'undefined') ? {} : callbackResult;
  return {
    style: callbackResult.style || group.options.drawPoints.style,
    styles: callbackResult.styles || group.options.drawPoints.styles,
    size: callbackResult.size || group.options.drawPoints.size,
    className: callbackResult.className || group.className
  };
}

/**
 *
 * @param {Object} framework            | SVG DOM element
 * @param {vis.Group} group
 * @returns {function}
 */
function getCallback(framework, group) {
  var callback = undefined;
  // check for the graph2d onRender
  if (framework.options && framework.options.drawPoints && framework.options.drawPoints.onRender && typeof framework.options.drawPoints.onRender == 'function') {
    callback = framework.options.drawPoints.onRender;
  }

  // override it with the group onRender if defined
  if (group.group.options && group.group.options.drawPoints && group.group.options.drawPoints.onRender && typeof group.group.options.drawPoints.onRender == 'function') {
    callback = group.group.options.drawPoints.onRender;
  }
  return callback;
}

/**
 *
 * @param {vis.GraphGroup.id} groupId
 * @param {Object} options   // TODO: Describe options
 * @constructor Bargraph
 */
function Bargraph(groupId, options) {  // eslint-disable-line no-unused-vars
}

Bargraph.drawIcon = function (group, x, y, iconWidth, iconHeight, framework) {
  var fillHeight = iconHeight * 0.5;
  var outline = getSVGElement("rect", framework.svgElements, framework.svg);
  outline.setAttributeNS(null, "x", x);
  outline.setAttributeNS(null, "y", y - fillHeight);
  outline.setAttributeNS(null, "width", iconWidth);
  outline.setAttributeNS(null, "height", 2 * fillHeight);
  outline.setAttributeNS(null, "class", "vis-outline");

  var barWidth = Math.round(0.3 * iconWidth);
  var originalWidth = group.options.barChart.width;
  var scale = originalWidth / barWidth;
  var bar1Height = Math.round(0.4 * iconHeight);
  var bar2Height = Math.round(0.75 * iconHeight);

  var offset = Math.round((iconWidth - (2 * barWidth)) / 3);

  drawBar(x + 0.5 * barWidth + offset, y + fillHeight - bar1Height - 1, barWidth, bar1Height, group.className + ' vis-bar', framework.svgElements, framework.svg, group.style);
  drawBar(x + 1.5 * barWidth + offset + 2, y + fillHeight - bar2Height - 1, barWidth, bar2Height, group.className + ' vis-bar', framework.svgElements, framework.svg, group.style);

  if (group.options.drawPoints.enabled == true) {
    var groupTemplate = {
      style: group.options.drawPoints.style,
      styles: group.options.drawPoints.styles,
      size: (group.options.drawPoints.size / scale),
      className: group.className
    };
    drawPoint(x + 0.5 * barWidth + offset, y + fillHeight - bar1Height - 1, groupTemplate, framework.svgElements, framework.svg);
    drawPoint(x + 1.5 * barWidth + offset + 2, y + fillHeight - bar2Height - 1, groupTemplate, framework.svgElements, framework.svg);
  }
};

/**
 * draw a bar graph
 *
 * @param {Array.<vis.GraphGroup.id>} groupIds
 * @param {Object} processedGroupData
 * @param {{svg: Object, svgElements: Array.<Object>, options: Object, groups: Array.<vis.Group>}} framework
 */
Bargraph.draw = function (groupIds, processedGroupData, framework) {
  var combinedData = [];
  var intersections = {};
  var coreDistance;
  var key, drawData;
  var group;
  var i, j;
  var barPoints = 0;

  // combine all barchart data
  for (i = 0; i < groupIds.length; i++) {
    group = framework.groups[groupIds[i]];
    if (group.options.style === 'bar') {
      if (group.visible === true && (framework.options.groups.visibility[groupIds[i]] === undefined || framework.options.groups.visibility[groupIds[i]] === true)) {
        for (j = 0; j < processedGroupData[groupIds[i]].length; j++) {
          combinedData.push({
            screen_x: processedGroupData[groupIds[i]][j].screen_x,
            screen_end: processedGroupData[groupIds[i]][j].screen_end,
            screen_y: processedGroupData[groupIds[i]][j].screen_y,
            x: processedGroupData[groupIds[i]][j].x,
            end: processedGroupData[groupIds[i]][j].end,
            y: processedGroupData[groupIds[i]][j].y,
            groupId: groupIds[i],
            label: processedGroupData[groupIds[i]][j].label
          });
          barPoints += 1;
        }
      }
    }
  }

  if (barPoints === 0) {
    return;
  }

  // sort by time and by group
  combinedData.sort(function (a, b) {
    if (a.screen_x === b.screen_x) {
      return a.groupId < b.groupId ? -1 : 1;
    }
    else {
      return a.screen_x - b.screen_x;
    }
  });

  // get intersections
  Bargraph._getDataIntersections(intersections, combinedData);

  // plot barchart
  for (i = 0; i < combinedData.length; i++) {
    group = framework.groups[combinedData[i].groupId];
    var minWidth = group.options.barChart.minWidth != undefined ? group.options.barChart.minWidth : 0.1 * group.options.barChart.width;

    key = combinedData[i].screen_x;
    var heightOffset = 0;
    if (intersections[key] === undefined) {
      if (i + 1 < combinedData.length) {
        coreDistance = Math.abs(combinedData[i + 1].screen_x - key);
      }
      drawData = Bargraph._getSafeDrawData(coreDistance, group, minWidth);
    }
    else {
      var nextKey = i + (intersections[key].amount - intersections[key].resolved);
      if (nextKey < combinedData.length) {
        coreDistance = Math.abs(combinedData[nextKey].screen_x - key);
      }
      drawData = Bargraph._getSafeDrawData(coreDistance, group, minWidth);
      intersections[key].resolved += 1;

      if (group.options.stack === true && group.options.excludeFromStacking !== true) {
        if (combinedData[i].screen_y < group.zeroPosition) {
          heightOffset = intersections[key].accumulatedNegative;
          intersections[key].accumulatedNegative += group.zeroPosition - combinedData[i].screen_y;
        }
        else {
          heightOffset = intersections[key].accumulatedPositive;
          intersections[key].accumulatedPositive += group.zeroPosition - combinedData[i].screen_y;
        }
      }
      else if (group.options.barChart.sideBySide === true) {
        drawData.width = drawData.width / intersections[key].amount;
        drawData.offset += (intersections[key].resolved) * drawData.width - (0.5 * drawData.width * (intersections[key].amount + 1));
      }
    }
    
    let dataWidth = drawData.width;
    let start = combinedData[i].screen_x;

    // are we drawing explicit boxes? (we supplied an end value)
    if (combinedData[i].screen_end != undefined){
      dataWidth = combinedData[i].screen_end - combinedData[i].screen_x;
      start += (dataWidth * 0.5);
    }
    else {
      start += drawData.offset;
    }

    drawBar(start, combinedData[i].screen_y - heightOffset, dataWidth, group.zeroPosition - combinedData[i].screen_y, group.className + ' vis-bar', framework.svgElements, framework.svg, group.style);

    // draw points
    if (group.options.drawPoints.enabled === true) {
      let pointData = {
        screen_x: combinedData[i].screen_x,
        screen_y: combinedData[i].screen_y - heightOffset,
        x: combinedData[i].x,
        y: combinedData[i].y,
        groupId: combinedData[i].groupId,
        label: combinedData[i].label
      };
      Points.draw([pointData], group, framework, drawData.offset);
      //DOMutil.drawPoint(combinedData[i].x + drawData.offset, combinedData[i].y, group, framework.svgElements, framework.svg);
    }
  }
};


/**
 * Fill the intersections object with counters of how many datapoints share the same x coordinates
 * @param {Object} intersections
 * @param {Array.<Object>} combinedData
 * @private
 */
Bargraph._getDataIntersections = function (intersections, combinedData) {
  // get intersections
  var coreDistance;
  for (var i = 0; i < combinedData.length; i++) {
    if (i + 1 < combinedData.length) {
      coreDistance = Math.abs(combinedData[i + 1].screen_x - combinedData[i].screen_x);
    }
    if (i > 0) {
      coreDistance = Math.min(coreDistance, Math.abs(combinedData[i - 1].screen_x - combinedData[i].screen_x));
    }
    if (coreDistance === 0) {
      if (intersections[combinedData[i].screen_x] === undefined) {
        intersections[combinedData[i].screen_x] = {
          amount: 0,
          resolved: 0,
          accumulatedPositive: 0,
          accumulatedNegative: 0
        };
      }
      intersections[combinedData[i].screen_x].amount += 1;
    }
  }
};


/**
 * Get the width and offset for bargraphs based on the coredistance between datapoints
 *
 * @param {number} coreDistance
 * @param {vis.Group} group
 * @param {number} minWidth
 * @returns {{width: number, offset: number}}
 * @private
 */
Bargraph._getSafeDrawData = function (coreDistance, group, minWidth) {
  var width, offset;
  if (coreDistance < group.options.barChart.width && coreDistance > 0) {
    width = coreDistance < minWidth ? minWidth : coreDistance;

    offset = 0; // recalculate offset with the new width;
    if (group.options.barChart.align === 'left') {
      offset -= 0.5 * coreDistance;
    }
    else if (group.options.barChart.align === 'right') {
      offset += 0.5 * coreDistance;
    }
  }
  else {
    // default settings
    width = group.options.barChart.width;
    offset = 0;
    if (group.options.barChart.align === 'left') {
      offset -= 0.5 * group.options.barChart.width;
    }
    else if (group.options.barChart.align === 'right') {
      offset += 0.5 * group.options.barChart.width;
    }
  }

  return {width: width, offset: offset};
};

Bargraph.getStackedYRange = function (combinedData, groupRanges, groupIds, groupLabel, orientation) {
  if (combinedData.length > 0) {
    // sort by time and by group
    combinedData.sort(function (a, b) {
      if (a.screen_x === b.screen_x) {
        return a.groupId < b.groupId ? -1 : 1;
      }
      else {
        return a.screen_x - b.screen_x;
      }
    });
    var intersections = {};

    Bargraph._getDataIntersections(intersections, combinedData);
    groupRanges[groupLabel] = Bargraph._getStackedYRange(intersections, combinedData);
    groupRanges[groupLabel].yAxisOrientation = orientation;
    groupIds.push(groupLabel);
  }
};

Bargraph._getStackedYRange = function (intersections, combinedData) {
  var key;
  var yMin = combinedData[0].screen_y;
  var yMax = combinedData[0].screen_y;
  for (var i = 0; i < combinedData.length; i++) {
    key = combinedData[i].screen_x;
    if (intersections[key] === undefined) {
      yMin = yMin > combinedData[i].screen_y ? combinedData[i].screen_y : yMin;
      yMax = yMax < combinedData[i].screen_y ? combinedData[i].screen_y : yMax;
    }
    else {
      if (combinedData[i].screen_y < 0) {
        intersections[key].accumulatedNegative += combinedData[i].screen_y;
      }
      else {
        intersections[key].accumulatedPositive += combinedData[i].screen_y;
      }
    }
  }
  for (var xpos in intersections) {
    if (intersections.hasOwnProperty(xpos)) {
      yMin = yMin > intersections[xpos].accumulatedNegative ? intersections[xpos].accumulatedNegative : yMin;
      yMin = yMin > intersections[xpos].accumulatedPositive ? intersections[xpos].accumulatedPositive : yMin;
      yMax = yMax < intersections[xpos].accumulatedNegative ? intersections[xpos].accumulatedNegative : yMax;
      yMax = yMax < intersections[xpos].accumulatedPositive ? intersections[xpos].accumulatedPositive : yMax;
    }
  }

  return {min: yMin, max: yMax};
};

/**
 *
 * @param {vis.GraphGroup.id} groupId
 * @param {Object} options   // TODO: Describe options
 * @constructor Line
 */
function Line(groupId, options) {  // eslint-disable-line no-unused-vars
}

Line.calcPath = function (dataset, group) {
    if (dataset != null) {
        if (dataset.length > 0) {
            var d = [];

            // construct path from dataset
            if (group.options.interpolation.enabled == true) {
                d = Line._catmullRom(dataset, group);
            }
            else {
                d = Line._linear(dataset);
            }
            return d;
        }
    }
};

Line.drawIcon = function (group, x, y, iconWidth, iconHeight, framework) {
    var fillHeight = iconHeight * 0.5;
    var path, fillPath;

    var outline = getSVGElement("rect", framework.svgElements, framework.svg);
    outline.setAttributeNS(null, "x", x);
    outline.setAttributeNS(null, "y", y - fillHeight);
    outline.setAttributeNS(null, "width", iconWidth);
    outline.setAttributeNS(null, "height", 2 * fillHeight);
    outline.setAttributeNS(null, "class", "vis-outline");

    path = getSVGElement("path", framework.svgElements, framework.svg);
    path.setAttributeNS(null, "class", group.className);
    if (group.style !== undefined) {
        path.setAttributeNS(null, "style", group.style);
    }

    path.setAttributeNS(null, "d", "M" + x + "," + y + " L" + (x + iconWidth) + "," + y + "");
    if (group.options.shaded.enabled == true) {
        fillPath = getSVGElement("path", framework.svgElements, framework.svg);
        if (group.options.shaded.orientation == 'top') {
            fillPath.setAttributeNS(null, "d", "M" + x + ", " + (y - fillHeight) +
              "L" + x + "," + y + " L" + (x + iconWidth) + "," + y + " L" + (x + iconWidth) + "," + (y - fillHeight));
        }
        else {
            fillPath.setAttributeNS(null, "d", "M" + x + "," + y + " " +
              "L" + x + "," + (y + fillHeight) + " " +
              "L" + (x + iconWidth) + "," + (y + fillHeight) +
              "L" + (x + iconWidth) + "," + y);
        }
        fillPath.setAttributeNS(null, "class", group.className + " vis-icon-fill");
        if (group.options.shaded.style !== undefined && group.options.shaded.style !== "") {
            fillPath.setAttributeNS(null, "style", group.options.shaded.style);
        }
    }

    if (group.options.drawPoints.enabled == true) {
        var groupTemplate = {
            style: group.options.drawPoints.style,
            styles: group.options.drawPoints.styles,
            size: group.options.drawPoints.size,
            className: group.className
        };
        drawPoint(x + 0.5 * iconWidth, y, groupTemplate, framework.svgElements, framework.svg);
    }
};

Line.drawShading = function (pathArray, group, subPathArray, framework) {
    // append shading to the path
    if (group.options.shaded.enabled == true) {
        var svgHeight = Number(framework.svg.style.height.replace('px',''));
        var fillPath = getSVGElement('path', framework.svgElements, framework.svg);
        var type = "L";
        if (group.options.interpolation.enabled == true){
            type = "C";
        }
        var dFill;
        var zero = 0;
        if (group.options.shaded.orientation == 'top') {
            zero = 0;
        }
        else if (group.options.shaded.orientation == 'bottom') {
            zero = svgHeight;
        }
        else {
            zero = Math.min(Math.max(0, group.zeroPosition), svgHeight);
        }
        if (group.options.shaded.orientation == 'group' && (subPathArray != null && subPathArray != undefined)) {
            dFill = 'M' + pathArray[0][0]+ ","+pathArray[0][1] + " " +
                    this.serializePath(pathArray,type,false) +
                    ' L'+ subPathArray[subPathArray.length-1][0]+ "," + subPathArray[subPathArray.length-1][1] + " " +
                    this.serializePath(subPathArray,type,true) +
                    subPathArray[0][0]+ ","+subPathArray[0][1] + " Z";
        }
        else {
            dFill = 'M' + pathArray[0][0]+ ","+pathArray[0][1] + " " +
                    this.serializePath(pathArray,type,false) +
                    ' V' + zero + ' H'+ pathArray[0][0] + " Z";
        }

        fillPath.setAttributeNS(null, 'class', group.className + ' vis-fill');
        if (group.options.shaded.style !== undefined) {
            fillPath.setAttributeNS(null, 'style', group.options.shaded.style);
        }
        fillPath.setAttributeNS(null, 'd', dFill);
    }
};

/**
 * draw a line graph
 *
 * @param {Array.<Object>} pathArray
 * @param {vis.Group} group
 * @param {{svg: Object, svgElements: Array.<Object>, options: Object, groups: Array.<vis.Group>}} framework
 */
Line.draw = function (pathArray, group, framework) {
    if (pathArray != null && pathArray != undefined) {
        var path = getSVGElement('path', framework.svgElements, framework.svg);
        path.setAttributeNS(null, "class", group.className);
        if (group.style !== undefined) {
            path.setAttributeNS(null, "style", group.style);
        }

        var type = "L";
        if (group.options.interpolation.enabled == true){
            type = "C";
        }
        // copy properties to path for drawing.
        path.setAttributeNS(null, 'd', 'M' + pathArray[0][0]+ ","+pathArray[0][1] + " " + this.serializePath(pathArray,type,false));
    }
};

Line.serializePath = function(pathArray,type,inverse){
    if (pathArray.length < 2){
        //Too little data to create a path.
        return "";
    }
    var d = type;
    var i;
    if (inverse){
        for (i = pathArray.length-2; i > 0; i--){
            d += pathArray[i][0] + "," + pathArray[i][1] + " ";
        }
    }
    else {
        for (i = 1; i < pathArray.length; i++){
            d += pathArray[i][0] + "," + pathArray[i][1] + " ";
        }
    }
    return d;
};

/**
 * This uses an uniform parametrization of the interpolation algorithm:
 * 'On the Parameterization of Catmull-Rom Curves' by Cem Yuksel et al.
 * @param {Array.<Object>} data
 * @returns {string}
 * @private
 */
Line._catmullRomUniform = function (data) {
    // catmull rom
    var p0, p1, p2, p3, bp1, bp2;
    var d = [];
    d.push( [ Math.round(data[0].screen_x) , Math.round(data[0].screen_y) ]);
    var normalization = 1 / 6;
    var length = data.length;
    for (var i = 0; i < length - 1; i++) {

        p0 = (i == 0) ? data[0] : data[i - 1];
        p1 = data[i];
        p2 = data[i + 1];
        p3 = (i + 2 < length) ? data[i + 2] : p2;


        // Catmull-Rom to Cubic Bezier conversion matrix
        //    0       1       0       0
        //  -1/6      1      1/6      0
        //    0      1/6      1     -1/6
        //    0       0       1       0

        //    bp0 = { x: p1.x,                               y: p1.y };
        bp1 = {
            screen_x: ((-p0.screen_x + 6 * p1.screen_x + p2.screen_x) * normalization),
            screen_y: ((-p0.screen_y + 6 * p1.screen_y + p2.screen_y) * normalization)
        };
        bp2 = {
            screen_x: (( p1.screen_x + 6 * p2.screen_x - p3.screen_x) * normalization),
            screen_y: (( p1.screen_y + 6 * p2.screen_y - p3.screen_y) * normalization)
        };
        //    bp0 = { x: p2.x,                               y: p2.y };

        d.push( [ bp1.screen_x , bp1.screen_y ]);
        d.push( [ bp2.screen_x , bp2.screen_y ]);
        d.push( [ p2.screen_x  , p2.screen_y  ]);
    }

    return d;
};

/**
 * This uses either the chordal or centripetal parameterization of the catmull-rom algorithm.
 * By default, the centripetal parameterization is used because this gives the nicest results.
 * These parameterizations are relatively heavy because the distance between 4 points have to be calculated.
 *
 * One optimization can be used to reuse distances since this is a sliding window approach.
 * @param {Array.<Object>} data
 * @param {vis.GraphGroup} group
 * @returns {string}
 * @private
 */
Line._catmullRom = function (data, group) {
    var alpha = group.options.interpolation.alpha;
    if (alpha == 0 || alpha === undefined) {
        return this._catmullRomUniform(data);
    }
    else {
        var p0, p1, p2, p3, bp1, bp2, d1, d2, d3, A, B, N, M;
        var d3powA, d2powA, d3pow2A, d2pow2A, d1pow2A, d1powA;
        var d = [];
        d.push( [ Math.round(data[0].screen_x) , Math.round(data[0].screen_y) ]);
        var length = data.length;
        for (var i = 0; i < length - 1; i++) {

            p0 = (i == 0) ? data[0] : data[i - 1];
            p1 = data[i];
            p2 = data[i + 1];
            p3 = (i + 2 < length) ? data[i + 2] : p2;

            d1 = Math.sqrt(Math.pow(p0.screen_x - p1.screen_x, 2) + Math.pow(p0.screen_y - p1.screen_y, 2));
            d2 = Math.sqrt(Math.pow(p1.screen_x - p2.screen_x, 2) + Math.pow(p1.screen_y - p2.screen_y, 2));
            d3 = Math.sqrt(Math.pow(p2.screen_x - p3.screen_x, 2) + Math.pow(p2.screen_y - p3.screen_y, 2));

            // Catmull-Rom to Cubic Bezier conversion matrix

            // A = 2d1^2a + 3d1^a * d2^a + d3^2a
            // B = 2d3^2a + 3d3^a * d2^a + d2^2a

            // [   0             1            0          0          ]
            // [   -d2^2a /N     A/N          d1^2a /N   0          ]
            // [   0             d3^2a /M     B/M        -d2^2a /M  ]
            // [   0             0            1          0          ]

            d3powA = Math.pow(d3, alpha);
            d3pow2A = Math.pow(d3, 2 * alpha);
            d2powA = Math.pow(d2, alpha);
            d2pow2A = Math.pow(d2, 2 * alpha);
            d1powA = Math.pow(d1, alpha);
            d1pow2A = Math.pow(d1, 2 * alpha);

            A = 2 * d1pow2A + 3 * d1powA * d2powA + d2pow2A;
            B = 2 * d3pow2A + 3 * d3powA * d2powA + d2pow2A;
            N = 3 * d1powA * (d1powA + d2powA);
            if (N > 0) {
                N = 1 / N;
            }
            M = 3 * d3powA * (d3powA + d2powA);
            if (M > 0) {
                M = 1 / M;
            }

            bp1 = {
                screen_x: ((-d2pow2A * p0.screen_x + A * p1.screen_x + d1pow2A * p2.screen_x) * N),
                screen_y: ((-d2pow2A * p0.screen_y + A * p1.screen_y + d1pow2A * p2.screen_y) * N)
            };

            bp2 = {
                screen_x: (( d3pow2A * p1.screen_x + B * p2.screen_x - d2pow2A * p3.screen_x) * M),
                screen_y: (( d3pow2A * p1.screen_y + B * p2.screen_y - d2pow2A * p3.screen_y) * M)
            };

            if (bp1.screen_x == 0 && bp1.screen_y == 0) {
                bp1 = p1;
            }
            if (bp2.screen_x == 0 && bp2.screen_y == 0) {
                bp2 = p2;
            }
            d.push( [ bp1.screen_x , bp1.screen_y ]);
            d.push( [ bp2.screen_x , bp2.screen_y ]);
            d.push( [ p2.screen_x  , p2.screen_y  ]);
        }

        return d;
    }
};

/**
 * this generates the SVG path for a linear drawing between datapoints.
 * @param {Array.<Object>} data
 * @returns {string}
 * @private
 */
Line._linear = function (data) {
    // linear
    var d = [];
    for (var i = 0; i < data.length; i++) {
        d.push([ data[i].screen_x , data[i].screen_y ]);
    }
    return d;
};

/**
 * /**
 * @param {object} group            | the object of the group from the dataset
 * @param {string} groupId          | ID of the group
 * @param {object} options          | the default options
 * @param {array} groupsUsingDefaultStyles  | this array has one entree.
 *                                            It is passed as an array so it is passed by reference.
 *                                            It enumerates through the default styles
 * @constructor GraphGroup
 */
function GraphGroup(group, groupId, options, groupsUsingDefaultStyles) {
  this.id = groupId;
  var fields = ['sampling', 'style', 'sort', 'yAxisOrientation', 'barChart', 'drawPoints', 'shaded', 'interpolation', 'zIndex','excludeFromStacking', 'excludeFromLegend'];
  this.options = util$3.selectiveBridgeObject(fields, options);
  this.usingDefaultStyle = group.className === undefined;
  this.groupsUsingDefaultStyles = groupsUsingDefaultStyles;
  this.zeroPosition = 0;
  this.update(group);
  if (this.usingDefaultStyle == true) {
    this.groupsUsingDefaultStyles[0] += 1;
  }
  this.itemsData = [];
  this.visible = group.visible === undefined ? true : group.visible;
}

/**
 * this loads a reference to all items in this group into this group.
 * @param {array} items
 */
GraphGroup.prototype.setItems = function (items) {
  if (items != null) {
    this.itemsData = items;
    if (this.options.sort == true) {
      util$3.insertSort(this.itemsData,function (a, b) {
        return a.x > b.x ? 1 : -1;
      });
    }
  }
  else {
    this.itemsData = [];
  }
};

GraphGroup.prototype.getItems = function () {
  return this.itemsData;
};

/**
 * this is used for barcharts and shading, this way, we only have to calculate it once.
 * @param {number} pos
 */
GraphGroup.prototype.setZeroPosition = function (pos) {
  this.zeroPosition = pos;
};

/**
 * set the options of the graph group over the default options.
 * @param {Object} options
 */
GraphGroup.prototype.setOptions = function (options) {
  if (options !== undefined) {
    var fields = ['sampling', 'style', 'sort', 'yAxisOrientation', 'barChart', 'zIndex','excludeFromStacking', 'excludeFromLegend'];
    util$3.selectiveDeepExtend(fields, this.options, options);

    // if the group's drawPoints is a function delegate the callback to the onRender property
    if (typeof options.drawPoints == 'function') {
      options.drawPoints = {
        onRender: options.drawPoints
      };
    }

    util$3.mergeOptions(this.options, options, 'interpolation');
    util$3.mergeOptions(this.options, options, 'drawPoints');
    util$3.mergeOptions(this.options, options, 'shaded');

    if (options.interpolation) {
      if (typeof options.interpolation == 'object') {
        if (options.interpolation.parametrization) {
          if (options.interpolation.parametrization == 'uniform') {
            this.options.interpolation.alpha = 0;
          }
          else if (options.interpolation.parametrization == 'chordal') {
            this.options.interpolation.alpha = 1.0;
          }
          else {
            this.options.interpolation.parametrization = 'centripetal';
            this.options.interpolation.alpha = 0.5;
          }
        }
      }
    }
  }
};


/**
 * this updates the current group class with the latest group dataset entree, used in _updateGroup in linegraph
 * @param {vis.Group} group
 */
GraphGroup.prototype.update = function (group) {
  this.group = group;
  this.content = group.content || 'graph';
  this.className = group.className || this.className || 'vis-graph-group' + this.groupsUsingDefaultStyles[0] % 10;
  this.visible = group.visible === undefined ? true : group.visible;
  this.style = group.style;
  this.setOptions(group.options);
};

/**
 * return the legend entree for this group.
 *
 * @param {number} iconWidth
 * @param {number} iconHeight
 * @param {{svg: (*|Element), svgElements: Object, options: Object, groups: Array.<Object>}} framework
 * @param {number} x
 * @param {number} y
 * @returns {{icon: (*|Element), label: (*|string), orientation: *}}
 */
GraphGroup.prototype.getLegend = function (iconWidth, iconHeight, framework, x, y) {
  if (framework == undefined || framework == null) {
    var svg = document.createElementNS('http://www.w3.org/2000/svg', "svg");
    framework = {svg: svg, svgElements:{}, options: this.options, groups: [this]};
  }
  if (x == undefined || x == null){
    x = 0;
  }
  if (y == undefined || y == null){
    y = 0.5 * iconHeight;
  }
  switch (this.options.style){
    case "line":
      Line.drawIcon(this, x, y, iconWidth, iconHeight, framework);
      break;
    case "points": //explicit no break
    case "point":
      Points.drawIcon(this, x, y, iconWidth, iconHeight, framework);
      break;
    case "bar":
      Bargraph.drawIcon(this, x, y, iconWidth, iconHeight, framework);
      break;
  }
  return {icon: framework.svg, label: this.content, orientation: this.options.yAxisOrientation};
};

GraphGroup.prototype.getYRange = function (groupData) {
  var yMin = groupData[0].y;
  var yMax = groupData[0].y;
  for (var j = 0; j < groupData.length; j++) {
    yMin = yMin > groupData[j].y ? groupData[j].y : yMin;
    yMax = yMax < groupData[j].y ? groupData[j].y : yMax;
  }
  return {min: yMin, max: yMax, yAxisOrientation: this.options.yAxisOrientation};
};

/**
 * Legend for Graph2d
 *
 * @param {vis.Graph2d.body} body
 * @param {vis.Graph2d.options} options
 * @param {number} side
 * @param {vis.LineGraph.options} linegraphOptions
 * @constructor Legend
 * @extends Component
 */
function Legend(body, options, side, linegraphOptions) {
  this.body = body;
  this.defaultOptions = {
    enabled: false,
    icons: true,
    iconSize: 20,
    iconSpacing: 6,
    left: {
      visible: true,
      position: 'top-left' // top/bottom - left,center,right
    },
    right: {
      visible: true,
      position: 'top-right' // top/bottom - left,center,right
    }
  };

  this.side = side;
  this.options = util$3.extend({}, this.defaultOptions);
  this.linegraphOptions = linegraphOptions;

  this.svgElements = {};
  this.dom = {};
  this.groups = {};
  this.amountOfGroups = 0;
  this._create();
  this.framework = {svg: this.svg, svgElements: this.svgElements, options: this.options, groups: this.groups};

  this.setOptions(options);
}

Legend.prototype = new Component();

Legend.prototype.clear = function() {
  this.groups = {};
  this.amountOfGroups = 0;
};

Legend.prototype.addGroup = function(label, graphOptions) {

  // Include a group only if the group option 'excludeFromLegend: false' is not set.
  if (graphOptions.options.excludeFromLegend != true) {
    if (!this.groups.hasOwnProperty(label)) {
      this.groups[label] = graphOptions;
    }
    this.amountOfGroups += 1;
  }
};

Legend.prototype.updateGroup = function(label, graphOptions) {
  this.groups[label] = graphOptions;
};

Legend.prototype.removeGroup = function(label) {
  if (this.groups.hasOwnProperty(label)) {
    delete this.groups[label];
    this.amountOfGroups -= 1;
  }
};

Legend.prototype._create = function() {
  this.dom.frame = document.createElement('div');
  this.dom.frame.className = 'vis-legend';
  this.dom.frame.style.position = "absolute";
  this.dom.frame.style.top = "10px";
  this.dom.frame.style.display = "block";

  this.dom.textArea = document.createElement('div');
  this.dom.textArea.className = 'vis-legend-text';
  this.dom.textArea.style.position = "relative";
  this.dom.textArea.style.top = "0px";

  this.svg = document.createElementNS('http://www.w3.org/2000/svg',"svg");
  this.svg.style.position = 'absolute';
  this.svg.style.top = 0 +'px';
  this.svg.style.width = this.options.iconSize + 5 + 'px';
  this.svg.style.height = '100%';

  this.dom.frame.appendChild(this.svg);
  this.dom.frame.appendChild(this.dom.textArea);
};

/**
 * Hide the component from the DOM
 */
Legend.prototype.hide = function() {
  // remove the frame containing the items
  if (this.dom.frame.parentNode) {
    this.dom.frame.parentNode.removeChild(this.dom.frame);
  }
};

/**
 * Show the component in the DOM (when not already visible).
 */
Legend.prototype.show = function() {
  // show frame containing the items
  if (!this.dom.frame.parentNode) {
    this.body.dom.center.appendChild(this.dom.frame);
  }
};

Legend.prototype.setOptions = function(options) {
  var fields = ['enabled','orientation','icons','left','right'];
  util$3.selectiveDeepExtend(fields, this.options, options);
};

Legend.prototype.redraw = function() {
  var activeGroups = 0;
  var groupArray = Object.keys(this.groups);
  groupArray.sort(function (a,b) {
    return (a < b ? -1 : 1);
  });

  for (var i = 0; i < groupArray.length; i++) {
    var groupId = groupArray[i];
    if (this.groups[groupId].visible == true && (this.linegraphOptions.visibility[groupId] === undefined || this.linegraphOptions.visibility[groupId] == true)) {
      activeGroups++;
    }
  }

  if (this.options[this.side].visible == false || this.amountOfGroups == 0 || this.options.enabled == false || activeGroups == 0) {
    this.hide();
  }
  else {
    this.show();
    if (this.options[this.side].position == 'top-left' || this.options[this.side].position == 'bottom-left') {
      this.dom.frame.style.left = '4px';
      this.dom.frame.style.textAlign = "left";
      this.dom.textArea.style.textAlign = "left";
      this.dom.textArea.style.left = (this.options.iconSize + 15) + 'px';
      this.dom.textArea.style.right = '';
      this.svg.style.left = 0 +'px';
      this.svg.style.right = '';
    }
    else {
      this.dom.frame.style.right = '4px';
      this.dom.frame.style.textAlign = "right";
      this.dom.textArea.style.textAlign = "right";
      this.dom.textArea.style.right = (this.options.iconSize + 15) + 'px';
      this.dom.textArea.style.left = '';
      this.svg.style.right = 0 +'px';
      this.svg.style.left = '';
    }

    if (this.options[this.side].position == 'top-left' || this.options[this.side].position == 'top-right') {
      this.dom.frame.style.top = 4 - Number(this.body.dom.center.style.top.replace("px","")) + 'px';
      this.dom.frame.style.bottom = '';
    }
    else {
      var scrollableHeight = this.body.domProps.center.height - this.body.domProps.centerContainer.height;
      this.dom.frame.style.bottom = 4 + scrollableHeight + Number(this.body.dom.center.style.top.replace("px","")) + 'px';
      this.dom.frame.style.top = '';
    }

    if (this.options.icons == false) {
      this.dom.frame.style.width = this.dom.textArea.offsetWidth + 10 + 'px';
      this.dom.textArea.style.right = '';
      this.dom.textArea.style.left = '';
      this.svg.style.width = '0px';
    }
    else {
      this.dom.frame.style.width = this.options.iconSize + 15 + this.dom.textArea.offsetWidth + 10 + 'px';
      this.drawLegendIcons();
    }

    var content = '';
    for (i = 0; i < groupArray.length; i++) {
      groupId = groupArray[i];
      if (this.groups[groupId].visible == true && (this.linegraphOptions.visibility[groupId] === undefined || this.linegraphOptions.visibility[groupId] == true)) {
        content += this.groups[groupId].content + '<br />';
      }
    }
    this.dom.textArea.innerHTML = util$3.xss(content);
    this.dom.textArea.style.lineHeight = ((0.75 * this.options.iconSize) + this.options.iconSpacing) + 'px';
  }
};

Legend.prototype.drawLegendIcons = function() {
  if (this.dom.frame.parentNode) {
    var groupArray = Object.keys(this.groups);
    groupArray.sort(function (a,b) {
      return (a < b ? -1 : 1);
    });

    // this resets the elements so the order is maintained
    resetElements(this.svgElements);

    var padding = window.getComputedStyle(this.dom.frame).paddingTop;
    var iconOffset = Number(padding.replace('px',''));
    var x = iconOffset;
    var iconWidth = this.options.iconSize;
    var iconHeight = 0.75 * this.options.iconSize;
    var y = iconOffset + 0.5 * iconHeight + 3;

    this.svg.style.width = iconWidth + 5 + iconOffset + 'px';

    for (var i = 0; i < groupArray.length; i++) {
      var groupId = groupArray[i];
      if (this.groups[groupId].visible == true && (this.linegraphOptions.visibility[groupId] === undefined || this.linegraphOptions.visibility[groupId] == true)) {
        this.groups[groupId].getLegend(iconWidth, iconHeight, this.framework, x, y);
        y += iconHeight + this.options.iconSpacing;
      }
    }
  }
};

var UNGROUPED$3 = '__ungrouped__'; // reserved group id for ungrouped items

/**
 * This is the constructor of the LineGraph. It requires a Timeline body and options.
 *
 * @param {vis.Timeline.body} body
 * @param {Object} options
 * @constructor LineGraph
 * @extends Component
 */
function LineGraph(body, options) {
  this.id = dist.v4();
  this.body = body;

  this.defaultOptions = {
    yAxisOrientation: 'left',
    defaultGroup: 'default',
    sort: true,
    sampling: true,
    stack: false,
    graphHeight: '400px',
    shaded: {
      enabled: false,
      orientation: 'bottom' // top, bottom, zero
    },
    style: 'line', // line, bar
    barChart: {
      width: 50,
      sideBySide: false,
      align: 'center' // left, center, right
    },
    interpolation: {
      enabled: true,
      parametrization: 'centripetal', // uniform (alpha = 0.0), chordal (alpha = 1.0), centripetal (alpha = 0.5)
      alpha: 0.5
    },
    drawPoints: {
      enabled: true,
      size: 6,
      style: 'square' // square, circle
    },
    dataAxis: {}, //Defaults are done on DataAxis level
    legend: {}, //Defaults are done on Legend level
    groups: {
      visibility: {}
    }
  };

  // options is shared by this lineGraph and all its items
  this.options = util$3.extend({}, this.defaultOptions);
  this.dom = {};
  this.props = {};
  this.hammer = null;
  this.groups = {};
  this.abortedGraphUpdate = false;
  this.updateSVGheight = false;
  this.updateSVGheightOnResize = false;
  this.forceGraphUpdate = true;

  var me = this;
  this.itemsData = null;    // DataSet
  this.groupsData = null;   // DataSet

  // listeners for the DataSet of the items
  this.itemListeners = {
    'add': function (event, params, senderId) {  // eslint-disable-line no-unused-vars
      me._onAdd(params.items);
    },
    'update': function (event, params, senderId) {  // eslint-disable-line no-unused-vars
      me._onUpdate(params.items);
    },
    'remove': function (event, params, senderId) {  // eslint-disable-line no-unused-vars
      me._onRemove(params.items);
    }
  };

  // listeners for the DataSet of the groups
  this.groupListeners = {
    'add': function (event, params, senderId) {  // eslint-disable-line no-unused-vars
      me._onAddGroups(params.items);
    },
    'update': function (event, params, senderId) {  // eslint-disable-line no-unused-vars
      me._onUpdateGroups(params.items);
    },
    'remove': function (event, params, senderId) {  // eslint-disable-line no-unused-vars
      me._onRemoveGroups(params.items);
    }
  };

  this.items = {};      // object with an Item for every data item
  this.selection = [];  // list with the ids of all selected nodes
  this.lastStart = this.body.range.start;
  this.touchParams = {}; // stores properties while dragging

  this.svgElements = {};
  this.setOptions(options);
  this.groupsUsingDefaultStyles = [0];
  this.body.emitter.on('rangechanged', function () {
    me.svg.style.left = util$3.option.asSize(-me.props.width);

    me.forceGraphUpdate = true;
    //Is this local redraw necessary? (Core also does a change event!)
    me.redraw.call(me);
  });

  // create the HTML DOM
  this._create();
  this.framework = {svg: this.svg, svgElements: this.svgElements, options: this.options, groups: this.groups};
}

LineGraph.prototype = new Component();

/**
 * Create the HTML DOM for the ItemSet
 */
LineGraph.prototype._create = function () {
  var frame = document.createElement('div');
  frame.className = 'vis-line-graph';
  this.dom.frame = frame;

  // create svg element for graph drawing.
  this.svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
  this.svg.style.position = 'relative';
  this.svg.style.height = ('' + this.options.graphHeight).replace('px', '') + 'px';
  this.svg.style.display = 'block';
  frame.appendChild(this.svg);

  // data axis
  this.options.dataAxis.orientation = 'left';
  this.yAxisLeft = new DataAxis(this.body, this.options.dataAxis, this.svg, this.options.groups);

  this.options.dataAxis.orientation = 'right';
  this.yAxisRight = new DataAxis(this.body, this.options.dataAxis, this.svg, this.options.groups);
  delete this.options.dataAxis.orientation;

  // legends
  this.legendLeft = new Legend(this.body, this.options.legend, 'left', this.options.groups);
  this.legendRight = new Legend(this.body, this.options.legend, 'right', this.options.groups);

  this.show();
};

/**
 * set the options of the LineGraph. the mergeOptions is used for subObjects that have an enabled element.
 * @param {object} options
 */
LineGraph.prototype.setOptions = function (options) {
  if (options) {
    var fields = ['sampling', 'defaultGroup', 'stack', 'height', 'graphHeight', 'yAxisOrientation', 'style', 'barChart', 'dataAxis', 'sort', 'groups'];
    if (options.graphHeight === undefined && options.height !== undefined) {
      this.updateSVGheight = true;
      this.updateSVGheightOnResize = true;
    }
    else if (this.body.domProps.centerContainer.height !== undefined && options.graphHeight !== undefined) {
      if (parseInt((options.graphHeight + '').replace("px", '')) < this.body.domProps.centerContainer.height) {
        this.updateSVGheight = true;
      }
    }
    util$3.selectiveDeepExtend(fields, this.options, options);
    util$3.mergeOptions(this.options, options, 'interpolation');
    util$3.mergeOptions(this.options, options, 'drawPoints');
    util$3.mergeOptions(this.options, options, 'shaded');
    util$3.mergeOptions(this.options, options, 'legend');

    if (options.interpolation) {
      if (typeof options.interpolation == 'object') {
        if (options.interpolation.parametrization) {
          if (options.interpolation.parametrization == 'uniform') {
            this.options.interpolation.alpha = 0;
          }
          else if (options.interpolation.parametrization == 'chordal') {
            this.options.interpolation.alpha = 1.0;
          }
          else {
            this.options.interpolation.parametrization = 'centripetal';
            this.options.interpolation.alpha = 0.5;
          }
        }
      }
    }

    if (this.yAxisLeft) {
      if (options.dataAxis !== undefined) {
        this.yAxisLeft.setOptions(this.options.dataAxis);
        this.yAxisRight.setOptions(this.options.dataAxis);
      }
    }

    if (this.legendLeft) {
      if (options.legend !== undefined) {
        this.legendLeft.setOptions(this.options.legend);
        this.legendRight.setOptions(this.options.legend);
      }
    }

    if (this.groups.hasOwnProperty(UNGROUPED$3)) {
      this.groups[UNGROUPED$3].setOptions(options);
    }
  }

  // this is used to redraw the graph if the visibility of the groups is changed.
  if (this.dom.frame) { //not on initial run?
    this.forceGraphUpdate=true;
    this.body.emitter.emit("_change",{queue: true});
  }
};

/**
 * Hide the component from the DOM
 */
LineGraph.prototype.hide = function () {
  // remove the frame containing the items
  if (this.dom.frame.parentNode) {
    this.dom.frame.parentNode.removeChild(this.dom.frame);
  }
};


/**
 * Show the component in the DOM (when not already visible).
 */
LineGraph.prototype.show = function () {
  // show frame containing the items
  if (!this.dom.frame.parentNode) {
    this.body.dom.center.appendChild(this.dom.frame);
  }
};


/**
 * Set items
 * @param {vis.DataSet | null} items
 */
LineGraph.prototype.setItems = function (items) {
  var me = this,
    ids,
    oldItemsData = this.itemsData;

  // replace the dataset
  if (!items) {
    this.itemsData = null;
  }
  else if (isDataViewLike("id", items)) {
    this.itemsData = typeCoerceDataSet(items);
  }
  else {
    throw new TypeError('Data must implement the interface of DataSet or DataView');
  }

  if (oldItemsData) {
    // unsubscribe from old dataset
    util$3.forEach(this.itemListeners, function (callback, event) {
      oldItemsData.off(event, callback);
    });

    // stop maintaining a coerced version of the old data set
    oldItemsData.dispose();

    // remove all drawn items
    ids = oldItemsData.getIds();
    this._onRemove(ids);
  }

  if (this.itemsData) {
    // subscribe to new dataset
    var id = this.id;
    util$3.forEach(this.itemListeners, function (callback, event) {
      me.itemsData.on(event, callback, id);
    });

    // add all new items
    ids = this.itemsData.getIds();
    this._onAdd(ids);
  }
};


/**
 * Set groups
 * @param {vis.DataSet} groups
 */
LineGraph.prototype.setGroups = function (groups) {
  var me = this;
  var ids;

  // unsubscribe from current dataset
  if (this.groupsData) {
    util$3.forEach(this.groupListeners, function (callback, event) {
      me.groupsData.off(event, callback);
    });

    // remove all drawn groups
    ids = this.groupsData.getIds();
    this.groupsData = null;
    for (var i = 0; i < ids.length; i++) {
      this._removeGroup(ids[i]);
    }
  }

  // replace the dataset
  if (!groups) {
    this.groupsData = null;
  }
  else if (isDataViewLike("id", groups)) {
    this.groupsData = groups;
  }
  else {
    throw new TypeError('Data must implement the interface of DataSet or DataView');
  }

  if (this.groupsData) {
    // subscribe to new dataset
    var id = this.id;
    util$3.forEach(this.groupListeners, function (callback, event) {
      me.groupsData.on(event, callback, id);
    });

    // draw all ms
    ids = this.groupsData.getIds();
    this._onAddGroups(ids);
  }
};

LineGraph.prototype._onUpdate = function (ids) {
  this._updateAllGroupData(ids);
};
LineGraph.prototype._onAdd = function (ids) {
  this._onUpdate(ids);
};
LineGraph.prototype._onRemove = function (ids) {
  this._onUpdate(ids);
};
LineGraph.prototype._onUpdateGroups = function (groupIds) {
  this._updateAllGroupData(null, groupIds);
};
LineGraph.prototype._onAddGroups = function (groupIds) {
  this._onUpdateGroups(groupIds);
};

/**
 * this cleans the group out off the legends and the dataaxis, updates the ungrouped and updates the graph
 * @param {Array} groupIds
 * @private
 */
LineGraph.prototype._onRemoveGroups = function (groupIds) {
  for (var i = 0; i < groupIds.length; i++) {
    this._removeGroup(groupIds[i]);
  }
  this.forceGraphUpdate = true;
  this.body.emitter.emit("_change",{queue: true});
};

/**
 * this cleans the group out off the legends and the dataaxis
 * @param {vis.GraphGroup.id} groupId
 * @private
 */
LineGraph.prototype._removeGroup = function (groupId) {
  if (this.groups.hasOwnProperty(groupId)) {
    if (this.groups[groupId].options.yAxisOrientation == 'right') {
      this.yAxisRight.removeGroup(groupId);
      this.legendRight.removeGroup(groupId);
      this.legendRight.redraw();
    }
    else {
      this.yAxisLeft.removeGroup(groupId);
      this.legendLeft.removeGroup(groupId);
      this.legendLeft.redraw();
    }
    delete this.groups[groupId];
  }
};

/**
 * update a group object with the group dataset entree
 *
 * @param {vis.GraphGroup} group
 * @param {vis.GraphGroup.id} groupId
 * @private
 */
LineGraph.prototype._updateGroup = function (group, groupId) {
  if (!this.groups.hasOwnProperty(groupId)) {
    this.groups[groupId] = new GraphGroup(group, groupId, this.options, this.groupsUsingDefaultStyles);
    if (this.groups[groupId].options.yAxisOrientation == 'right') {
      this.yAxisRight.addGroup(groupId, this.groups[groupId]);
      this.legendRight.addGroup(groupId, this.groups[groupId]);
    }
    else {
      this.yAxisLeft.addGroup(groupId, this.groups[groupId]);
      this.legendLeft.addGroup(groupId, this.groups[groupId]);
    }
  }
  else {
    this.groups[groupId].update(group);
    if (this.groups[groupId].options.yAxisOrientation == 'right') {
      this.yAxisRight.updateGroup(groupId, this.groups[groupId]);
      this.legendRight.updateGroup(groupId, this.groups[groupId]);
      //If yAxisOrientation changed, clean out the group from the other axis.
      this.yAxisLeft.removeGroup(groupId);
      this.legendLeft.removeGroup(groupId);
    }
    else {
      this.yAxisLeft.updateGroup(groupId, this.groups[groupId]);
      this.legendLeft.updateGroup(groupId, this.groups[groupId]);
      //If yAxisOrientation changed, clean out the group from the other axis.
      this.yAxisRight.removeGroup(groupId);
      this.legendRight.removeGroup(groupId);
    }
  }
  this.legendLeft.redraw();
  this.legendRight.redraw();
};


/**
 * this updates all groups, it is used when there is an update the the itemset.
 *
 * @param  {Array} ids
 * @param  {Array} groupIds
 * @private
 */
LineGraph.prototype._updateAllGroupData = function (ids, groupIds) {
  if (this.itemsData != null) {
    var groupsContent = {};
    var items = this.itemsData.get();
    var fieldId = this.itemsData.idProp;
    var idMap = {};
    if (ids){
      ids.map(function (id) {
        idMap[id] = id;
      });
    }

    //pre-Determine array sizes, for more efficient memory claim
    var groupCounts = {};
    for (var i = 0; i < items.length; i++) {
      var item = items[i];
      var groupId = item.group;
      if (groupId === null || groupId === undefined) {
        groupId = UNGROUPED$3;
      }
      groupCounts.hasOwnProperty(groupId) ? groupCounts[groupId]++ : groupCounts[groupId] = 1;
    }

    //Pre-load arrays from existing groups if items are not changed (not in ids)
    var existingItemsMap = {};
    if (!groupIds && ids) {
      for (groupId in this.groups) {
        if (this.groups.hasOwnProperty(groupId)) {
          group = this.groups[groupId];
          var existing_items = group.getItems();

          groupsContent[groupId] = existing_items.filter(function (item) {
            existingItemsMap[item[fieldId]] = item[fieldId];
            return (item[fieldId] !== idMap[item[fieldId]]);
          });
          var newLength = groupCounts[groupId];
          groupCounts[groupId] -= groupsContent[groupId].length;
          if (groupsContent[groupId].length < newLength) {
            groupsContent[groupId][newLength - 1] = {};
          }
        }
      }
    }

    //Now insert data into the arrays.
    for (i = 0; i < items.length; i++) {
      item = items[i];
      groupId = item.group;
      if (groupId === null || groupId === undefined) {
        groupId = UNGROUPED$3;
      }
      if (!groupIds && ids && (item[fieldId] !== idMap[item[fieldId]]) && existingItemsMap.hasOwnProperty(item[fieldId])) {
        continue;
      }
      if (!groupsContent.hasOwnProperty(groupId)) {
        groupsContent[groupId] = new Array(groupCounts[groupId]);
      }
      //Copy data (because of unmodifiable DataView input.
      var extended = util$3.bridgeObject(item);
      extended.x = util$3.convert(item.x, 'Date');
      extended.end = util$3.convert(item.end, 'Date');
      extended.orginalY = item.y; //real Y
      extended.y = Number(item.y);
      extended[fieldId] = item[fieldId];

      var index= groupsContent[groupId].length - groupCounts[groupId]--;
      groupsContent[groupId][index] = extended;
    }

    //Make sure all groups are present, to allow removal of old groups
    for (groupId in this.groups){
      if (this.groups.hasOwnProperty(groupId)){
        if (!groupsContent.hasOwnProperty(groupId)) {
          groupsContent[groupId] = new Array(0);
        }
      }
    }

    //Update legendas, style and axis
    for (groupId in groupsContent) {
      if (groupsContent.hasOwnProperty(groupId)) {
        if (groupsContent[groupId].length == 0) {
          if (this.groups.hasOwnProperty(groupId)) {
            this._removeGroup(groupId);
          }
        } else {
          var group = undefined;
          if (this.groupsData != undefined) {
            group = this.groupsData.get(groupId);
          }
          if (group == undefined) {
            group = {id: groupId, content: this.options.defaultGroup + groupId};
          }
          this._updateGroup(group, groupId);
          this.groups[groupId].setItems(groupsContent[groupId]);
        }
      }
    }
    this.forceGraphUpdate = true;
    this.body.emitter.emit("_change",{queue: true});
  }
};

/**
 * Redraw the component, mandatory function
 * @return {boolean} Returns true if the component is resized
 */
LineGraph.prototype.redraw = function () {
  var resized = false;

  // calculate actual size and position
  this.props.width = this.dom.frame.offsetWidth;
  this.props.height = this.body.domProps.centerContainer.height
    - this.body.domProps.border.top
    - this.body.domProps.border.bottom;

  // check if this component is resized
  resized = this._isResized() || resized;

  // check whether zoomed (in that case we need to re-stack everything)
  var visibleInterval = this.body.range.end - this.body.range.start;
  var zoomed = (visibleInterval != this.lastVisibleInterval);
  this.lastVisibleInterval = visibleInterval;


  // the svg element is three times as big as the width, this allows for fully dragging left and right
  // without reloading the graph. the controls for this are bound to events in the constructor
  if (resized == true) {
    this.svg.style.width = util$3.option.asSize(3 * this.props.width);
    this.svg.style.left = util$3.option.asSize(-this.props.width);

    // if the height of the graph is set as proportional, change the height of the svg
    if ((this.options.height + '').indexOf("%") != -1 || this.updateSVGheightOnResize == true) {
      this.updateSVGheight = true;
    }
  }

  // update the height of the graph on each redraw of the graph.
  if (this.updateSVGheight == true) {
    if (this.options.graphHeight != this.props.height + 'px') {
      this.options.graphHeight = this.props.height + 'px';
      this.svg.style.height = this.props.height + 'px';
    }
    this.updateSVGheight = false;
  }
  else {
    this.svg.style.height = ('' + this.options.graphHeight).replace('px', '') + 'px';
  }

  // zoomed is here to ensure that animations are shown correctly.
  if (resized == true || zoomed == true || this.abortedGraphUpdate == true || this.forceGraphUpdate == true) {
    resized = this._updateGraph() || resized;
    this.forceGraphUpdate = false;
    this.lastStart = this.body.range.start;
    this.svg.style.left = (-this.props.width) + 'px';
  }
  else {
    // move the whole svg while dragging
    if (this.lastStart != 0) {
      var offset = this.body.range.start - this.lastStart;
      var range = this.body.range.end - this.body.range.start;
      if (this.props.width != 0) {
        var rangePerPixelInv = this.props.width / range;
        var xOffset = offset * rangePerPixelInv;
        this.svg.style.left = (-this.props.width - xOffset) + 'px';
      }
    }
  }
  this.legendLeft.redraw();
  this.legendRight.redraw();
  return resized;
};


LineGraph.prototype._getSortedGroupIds = function(){
  // getting group Ids
  var grouplist = [];
  for (var groupId in this.groups) {
    if (this.groups.hasOwnProperty(groupId)) {
      var group = this.groups[groupId];
      if (group.visible == true && (this.options.groups.visibility[groupId] === undefined || this.options.groups.visibility[groupId] == true)) {
        grouplist.push({id:groupId,zIndex:group.options.zIndex});
      }
    }
  }
  util$3.insertSort(grouplist,function(a,b){
    var az = a.zIndex;
    var bz = b.zIndex;
    if (az === undefined) az=0;
    if (bz === undefined) bz=0;
    return az==bz? 0: (az<bz ? -1: 1);
  });
  var groupIds = new Array(grouplist.length);
  for (var i=0; i< grouplist.length; i++){
    groupIds[i] = grouplist[i].id;
  }
  return groupIds;
};

/**
 * Update and redraw the graph.
 *
 * @returns {boolean}
 * @private
 */
LineGraph.prototype._updateGraph = function () {
  // reset the svg elements
  prepareElements(this.svgElements);
  if (this.props.width != 0 && this.itemsData != null) {
    var group, i;
    var groupRanges = {};
    var changeCalled = false;
    // this is the range of the SVG canvas
    var minDate = this.body.util.toGlobalTime(-this.body.domProps.root.width);
    var maxDate = this.body.util.toGlobalTime(2 * this.body.domProps.root.width);

    // getting group Ids
    var groupIds = this._getSortedGroupIds();
    if (groupIds.length > 0) {
      var groupsData = {};

      // fill groups data, this only loads the data we require based on the timewindow
      this._getRelevantData(groupIds, groupsData, minDate, maxDate);

      // apply sampling, if disabled, it will pass through this function.
      this._applySampling(groupIds, groupsData);

      // we transform the X coordinates to detect collisions
      for (i = 0; i < groupIds.length; i++) {
        this._convertXcoordinates(groupsData[groupIds[i]]);
      }

      // now all needed data has been collected we start the processing.
      this._getYRanges(groupIds, groupsData, groupRanges);

      // update the Y axis first, we use this data to draw at the correct Y points
      changeCalled = this._updateYAxis(groupIds, groupRanges);

      //  at changeCalled, abort this update cycle as the graph needs another update with new Width input from the Redraw container.
      //  Cleanup SVG elements on abort.
      if (changeCalled == true) {
        cleanupElements(this.svgElements);
        this.abortedGraphUpdate = true;
        return true;
      }
      this.abortedGraphUpdate = false;

      // With the yAxis scaled correctly, use this to get the Y values of the points.
      var below = undefined;
      for (i = 0; i < groupIds.length; i++) {
        group = this.groups[groupIds[i]];
        if (this.options.stack === true && this.options.style === 'line') {
          if (group.options.excludeFromStacking == undefined || !group.options.excludeFromStacking) {
            if (below != undefined) {
              this._stack(groupsData[group.id], groupsData[below.id]);
              if (group.options.shaded.enabled == true && group.options.shaded.orientation !== "group"){
                if (group.options.shaded.orientation == "top" && below.options.shaded.orientation !== "group"){
                  below.options.shaded.orientation="group";
                  below.options.shaded.groupId=group.id;
                } else {
                  group.options.shaded.orientation="group";
                  group.options.shaded.groupId=below.id;
                }
              }
            }
            below = group;
          }
        }
        this._convertYcoordinates(groupsData[groupIds[i]], group);
      }

      //Precalculate paths and draw shading if appropriate. This will make sure the shading is always behind any lines.
      var paths = {};
      for (i = 0; i < groupIds.length; i++) {
        group = this.groups[groupIds[i]];
        if (group.options.style === 'line' && group.options.shaded.enabled == true) {
          var dataset = groupsData[groupIds[i]];
          if (dataset == null || dataset.length == 0) {
            continue;
          }
          if (!paths.hasOwnProperty(groupIds[i])) {
            paths[groupIds[i]] = Line.calcPath(dataset, group);
          }
          if (group.options.shaded.orientation === "group") {
            var subGroupId = group.options.shaded.groupId;
            if (groupIds.indexOf(subGroupId) === -1) {
              console.log(group.id + ": Unknown shading group target given:" + subGroupId);
              continue;
            }
            if (!paths.hasOwnProperty(subGroupId)) {
              paths[subGroupId] = Line.calcPath(groupsData[subGroupId], this.groups[subGroupId]);
            }
            Line.drawShading(paths[groupIds[i]], group, paths[subGroupId], this.framework);
          }
          else {
            Line.drawShading(paths[groupIds[i]], group, undefined, this.framework);
          }
        }
      }

      // draw the groups, calculating paths if still necessary.
      Bargraph.draw(groupIds, groupsData, this.framework);
      for (i = 0; i < groupIds.length; i++) {
        group = this.groups[groupIds[i]];
        if (groupsData[groupIds[i]].length > 0) {
          switch (group.options.style) {
            case "line":
              if (!paths.hasOwnProperty(groupIds[i])) {
                paths[groupIds[i]] = Line.calcPath(groupsData[groupIds[i]], group);
              }
              Line.draw(paths[groupIds[i]], group, this.framework);
            // eslint-disable-line no-fallthrough
            case "point":
            // eslint-disable-line no-fallthrough
            case "points":
              if (group.options.style == "point" || group.options.style == "points" || group.options.drawPoints.enabled == true) {
                Points.draw(groupsData[groupIds[i]], group, this.framework);
              }
              break;
            //do nothing...
          }
        }

      }
    }
  }

  // cleanup unused svg elements
  cleanupElements(this.svgElements);
  return false;
};

LineGraph.prototype._stack = function (data, subData) {
  var index, dx, dy, subPrevPoint, subNextPoint;
  index = 0;
  // for each data point we look for a matching on in the set below
  for (var j = 0; j < data.length; j++) {
    subPrevPoint = undefined;
    subNextPoint = undefined;
    // we look for time matches or a before-after point
    for (var k = index; k < subData.length; k++) {
      // if times match exactly
      if (subData[k].x === data[j].x) {
        subPrevPoint = subData[k];
        subNextPoint = subData[k];
        index = k;
        break;
      }
      else if (subData[k].x > data[j].x) { // overshoot
        subNextPoint = subData[k];
        if (k == 0) {
          subPrevPoint = subNextPoint;
        }
        else {
          subPrevPoint = subData[k - 1];
        }
        index = k;
        break;
      }
    }
    // in case the last data point has been used, we assume it stays like this.
    if (subNextPoint === undefined) {
      subPrevPoint = subData[subData.length - 1];
      subNextPoint = subData[subData.length - 1];
    }
    // linear interpolation
    dx = subNextPoint.x - subPrevPoint.x;
    dy = subNextPoint.y - subPrevPoint.y;
    if (dx == 0) {
      data[j].y = data[j].orginalY + subNextPoint.y;
    }
    else {
      data[j].y = data[j].orginalY + (dy / dx) * (data[j].x - subPrevPoint.x) + subPrevPoint.y; // ax + b where b is data[j].y
    }
  }
};


/**
 * first select and preprocess the data from the datasets.
 * the groups have their preselection of data, we now loop over this data to see
 * what data we need to draw. Sorted data is much faster.
 * more optimization is possible by doing the sampling before and using the binary search
 * to find the end date to determine the increment.
 *
 * @param {array}  groupIds
 * @param {object} groupsData
 * @param {date}   minDate
 * @param {date}   maxDate
 * @private
 */
LineGraph.prototype._getRelevantData = function (groupIds, groupsData, minDate, maxDate) {
  var group, i, j, item;
  if (groupIds.length > 0) {
    for (i = 0; i < groupIds.length; i++) {
      group = this.groups[groupIds[i]];
      var itemsData = group.getItems();
      // optimization for sorted data
      if (group.options.sort == true) {
        var dateComparator = function (a, b) {
          return a.getTime() == b.getTime() ? 0 : a < b ? -1 : 1
        };
        var first = Math.max(0, util$3.binarySearchValue(itemsData, minDate, 'x', 'before', dateComparator));
        var last = Math.min(itemsData.length, util$3.binarySearchValue(itemsData, maxDate, 'x', 'after', dateComparator) + 1);
        if (last <= 0) {
          last = itemsData.length;
        }
        var dataContainer = new Array(last-first);
        for (j = first; j < last; j++) {
          item = group.itemsData[j];
          dataContainer[j-first] = item;
        }
        groupsData[groupIds[i]] = dataContainer;
      }
      else {
        // If unsorted data, all data is relevant, just returning entire structure
        groupsData[groupIds[i]] = group.itemsData;
      }
    }
  }
};


/**
 *
 * @param {Array.<vis.GraphGroup.id>} groupIds
 * @param {vis.DataSet} groupsData
 * @private
 */
LineGraph.prototype._applySampling = function (groupIds, groupsData) {
  var group;
  if (groupIds.length > 0) {
    for (var i = 0; i < groupIds.length; i++) {
      group = this.groups[groupIds[i]];
      if (group.options.sampling == true) {
        var dataContainer = groupsData[groupIds[i]];
        if (dataContainer.length > 0) {
          var increment = 1;
          var amountOfPoints = dataContainer.length;

          // the global screen is used because changing the width of the yAxis may affect the increment, resulting in an endless loop
          // of width changing of the yAxis.
          //TODO: This assumes sorted data, but that's not guaranteed!
          var xDistance = this.body.util.toGlobalScreen(dataContainer[dataContainer.length - 1].x) - this.body.util.toGlobalScreen(dataContainer[0].x);
          var pointsPerPixel = amountOfPoints / xDistance;
          increment = Math.min(Math.ceil(0.2 * amountOfPoints), Math.max(1, Math.round(pointsPerPixel)));

          var sampledData = new Array(amountOfPoints);
          for (var j = 0; j < amountOfPoints; j += increment) {
            var idx = Math.round(j/increment);
            sampledData[idx]=dataContainer[j];
          }
          groupsData[groupIds[i]] = sampledData.splice(0,Math.round(amountOfPoints/increment));
        }
      }
    }
  }
};


/**
 *
 * @param {Array.<vis.GraphGroup.id>} groupIds
 * @param {vis.DataSet} groupsData
 * @param {object} groupRanges  | this is being filled here
 * @private
 */
LineGraph.prototype._getYRanges = function (groupIds, groupsData, groupRanges) {
  var groupData, group, i;
  var combinedDataLeft = [];
  var combinedDataRight = [];
  var options;
  if (groupIds.length > 0) {
    for (i = 0; i < groupIds.length; i++) {
      groupData = groupsData[groupIds[i]];
      options = this.groups[groupIds[i]].options;
      if (groupData.length > 0) {
        group = this.groups[groupIds[i]];
        // if bar graphs are stacked, their range need to be handled differently and accumulated over all groups.
        if (options.stack === true && options.style === 'bar') {
          if (options.yAxisOrientation === 'left') {
            combinedDataLeft = combinedDataLeft.concat(groupData);
          }
          else {
            combinedDataRight = combinedDataRight.concat(groupData);
          }
        }
        else {
          groupRanges[groupIds[i]] = group.getYRange(groupData, groupIds[i]);
        }
      }
    }

    // if bar graphs are stacked, their range need to be handled differently and accumulated over all groups.
    Bargraph.getStackedYRange(combinedDataLeft, groupRanges, groupIds, '__barStackLeft', 'left');
    Bargraph.getStackedYRange(combinedDataRight, groupRanges, groupIds, '__barStackRight', 'right');
  }
};


/**
 * this sets the Y ranges for the Y axis. It also determines which of the axis should be shown or hidden.
 * @param {Array.<vis.GraphGroup.id>} groupIds
 * @param {Object} groupRanges
 * @returns {boolean} resized
 * @private
 */
LineGraph.prototype._updateYAxis = function (groupIds, groupRanges) {
  var resized = false;
  var yAxisLeftUsed = false;
  var yAxisRightUsed = false;
  var minLeft = 1e9, minRight = 1e9, maxLeft = -1e9, maxRight = -1e9, minVal, maxVal;
  // if groups are present
  if (groupIds.length > 0) {
    // this is here to make sure that if there are no items in the axis but there are groups, that there is no infinite draw/redraw loop.
    for (var i = 0; i < groupIds.length; i++) {
      var group = this.groups[groupIds[i]];
      if (group && group.options.yAxisOrientation != 'right') {
        yAxisLeftUsed = true;
        minLeft = 1e9;
        maxLeft = -1e9;
      }
      else if (group && group.options.yAxisOrientation) {
        yAxisRightUsed = true;
        minRight = 1e9;
        maxRight = -1e9;
      }
    }

    // if there are items:
    for (i = 0; i < groupIds.length; i++) {
      if (groupRanges.hasOwnProperty(groupIds[i])) {
        if (groupRanges[groupIds[i]].ignore !== true) {
          minVal = groupRanges[groupIds[i]].min;
          maxVal = groupRanges[groupIds[i]].max;

          if (groupRanges[groupIds[i]].yAxisOrientation != 'right') {
            yAxisLeftUsed = true;
            minLeft = minLeft > minVal ? minVal : minLeft;
            maxLeft = maxLeft < maxVal ? maxVal : maxLeft;
          }
          else {
            yAxisRightUsed = true;
            minRight = minRight > minVal ? minVal : minRight;
            maxRight = maxRight < maxVal ? maxVal : maxRight;
          }
        }
      }
    }

    if (yAxisLeftUsed == true) {
      this.yAxisLeft.setRange(minLeft, maxLeft);
    }
    if (yAxisRightUsed == true) {
      this.yAxisRight.setRange(minRight, maxRight);
    }
  }
  resized = this._toggleAxisVisiblity(yAxisLeftUsed, this.yAxisLeft) || resized;
  resized = this._toggleAxisVisiblity(yAxisRightUsed, this.yAxisRight) || resized;

  if (yAxisRightUsed == true && yAxisLeftUsed == true) {
    this.yAxisLeft.drawIcons = true;
    this.yAxisRight.drawIcons = true;
  }
  else {
    this.yAxisLeft.drawIcons = false;
    this.yAxisRight.drawIcons = false;
  }
  this.yAxisRight.master = !yAxisLeftUsed;
  this.yAxisRight.masterAxis = this.yAxisLeft;

  if (this.yAxisRight.master == false) {
    if (yAxisRightUsed == true) {
      this.yAxisLeft.lineOffset = this.yAxisRight.width;
    }
    else {
      this.yAxisLeft.lineOffset = 0;
    }

    resized = this.yAxisLeft.redraw() || resized;
    resized = this.yAxisRight.redraw() || resized;
  }
  else {
    resized = this.yAxisRight.redraw() || resized;
  }

  // clean the accumulated lists
  var tempGroups = ['__barStackLeft', '__barStackRight', '__lineStackLeft', '__lineStackRight'];
  for (i = 0; i < tempGroups.length; i++) {
    if (groupIds.indexOf(tempGroups[i]) != -1) {
      groupIds.splice(groupIds.indexOf(tempGroups[i]), 1);
    }
  }

  return resized;
};


/**
 * This shows or hides the Y axis if needed. If there is a change, the changed event is emitted by the updateYAxis function
 *
 * @param {boolean} axisUsed
 * @param {vis.DataAxis}  axis
 * @returns {boolean}
 * @private
 */
LineGraph.prototype._toggleAxisVisiblity = function (axisUsed, axis) {
  var changed = false;
  if (axisUsed == false) {
    if (axis.dom.frame.parentNode && axis.hidden == false) {
      axis.hide();
      changed = true;
    }
  }
  else {
    if (!axis.dom.frame.parentNode && axis.hidden == true) {
      axis.show();
      changed = true;
    }
  }
  return changed;
};


/**
 * This uses the DataAxis object to generate the correct X coordinate on the SVG window. It uses the
 * util function toScreen to get the x coordinate from the timestamp. It also pre-filters the data and get the minMax ranges for
 * the yAxis.
 *
 * @param {Array.<Object>} datapoints
 * @private
 */
LineGraph.prototype._convertXcoordinates = function (datapoints) {
  var toScreen = this.body.util.toScreen;
  for (var i = 0; i < datapoints.length; i++) {
    datapoints[i].screen_x = toScreen(datapoints[i].x) + this.props.width;
    datapoints[i].screen_y = datapoints[i].y; //starting point for range calculations
    if (datapoints[i].end != undefined) {
      datapoints[i].screen_end = toScreen(datapoints[i].end) + this.props.width;
    }
    else {
      datapoints[i].screen_end = undefined;
    }
  }
};


/**
 * This uses the DataAxis object to generate the correct X coordinate on the SVG window. It uses the
 * util function toScreen to get the x coordinate from the timestamp. It also pre-filters the data and get the minMax ranges for
 * the yAxis.
 *
 * @param {Array.<Object>} datapoints
 * @param {vis.GraphGroup} group
 * @private
 */
LineGraph.prototype._convertYcoordinates = function (datapoints, group) {
  var axis = this.yAxisLeft;
  var svgHeight = Number(this.svg.style.height.replace('px', ''));
  if (group.options.yAxisOrientation == 'right') {
    axis = this.yAxisRight;
  }
  for (var i = 0; i < datapoints.length; i++) {
    datapoints[i].screen_y = Math.round(axis.convertValue(datapoints[i].y));
  }
  group.setZeroPosition(Math.min(svgHeight, axis.convertValue(0)));
};

/**
 * This object contains all possible options. It will check if the types are correct, if required if the option is one
 * of the allowed values.
 *
 * __any__ means that the name of the property does not matter.
 * __type__ is a required field for all objects and contains the allowed types of all objects
 */
let string$1 = 'string';
let bool$1 = 'boolean';
let number$1 = 'number';
let array$1 = 'array';
let date$1 = 'date';
let object$1 = 'object'; // should only be in a __type__ property
let dom$1 = 'dom';
let moment$2 = 'moment';
let any$1 = 'any';


let allOptions$2 = {
  configure: {
    enabled: {'boolean': bool$1},
    filter: {'boolean': bool$1,'function': 'function'},
    container: {dom: dom$1},
    __type__: {object: object$1,'boolean': bool$1,'function': 'function'}
  },

  //globals :
  alignCurrentTime: {string: string$1, 'undefined': 'undefined'},  
  yAxisOrientation: {string:['left','right']},
  defaultGroup: {string: string$1},
  sort: {'boolean': bool$1},
  sampling: {'boolean': bool$1},
  stack:{'boolean': bool$1},
  graphHeight: {string: string$1, number: number$1},
  shaded: {
    enabled: {'boolean': bool$1},
    orientation: {string:['bottom','top','zero','group']}, // top, bottom, zero, group
    groupId: {object: object$1},
    __type__: {'boolean': bool$1,object: object$1}
  },
  style: {string:['line','bar','points']}, // line, bar
  barChart: {
    width: {number: number$1},
    minWidth: {number: number$1},
    sideBySide: {'boolean': bool$1},
    align: {string:['left','center','right']},
    __type__: {object: object$1}
  },
  interpolation: {
    enabled: {'boolean': bool$1},
    parametrization: {string:['centripetal', 'chordal','uniform']}, // uniform (alpha = 0.0), chordal (alpha = 1.0), centripetal (alpha = 0.5)
    alpha: {number: number$1},
    __type__: {object: object$1,'boolean': bool$1}
  },
  drawPoints: {
    enabled: {'boolean': bool$1},
    onRender: { 'function': 'function' },
    size: {number: number$1},
    style: {string:['square','circle']}, // square, circle
    __type__: {object: object$1,'boolean': bool$1,'function': 'function'}
  },
  dataAxis: {
    showMinorLabels: {'boolean': bool$1},
    showMajorLabels: {'boolean': bool$1},
    showWeekScale: {'boolean': bool$1},
    icons: {'boolean': bool$1},
    width: {string: string$1, number: number$1},
    visible: {'boolean': bool$1},
    alignZeros: {'boolean': bool$1},
    left:{
      range: {min:{number: number$1,'undefined': 'undefined'},max:{number: number$1,'undefined': 'undefined'},__type__: {object: object$1}},
      format: {'function': 'function'},
      title: {text:{string: string$1,number: number$1,'undefined': 'undefined'},style:{string: string$1,'undefined': 'undefined'},__type__: {object: object$1}},
      __type__: {object: object$1}
    },
    right:{
      range: {min:{number: number$1,'undefined': 'undefined'},max:{number: number$1,'undefined': 'undefined'},__type__: {object: object$1}},
      format: {'function': 'function'},
      title: {text:{string: string$1,number: number$1,'undefined': 'undefined'},style:{string: string$1,'undefined': 'undefined'},__type__: {object: object$1}},
      __type__: {object: object$1}
    },
    __type__: {object: object$1}
  },
  legend: {
    enabled: {'boolean': bool$1},
    icons: {'boolean': bool$1},
    left: {
      visible: {'boolean': bool$1},
      position: {string:['top-right','bottom-right','top-left','bottom-left']},
      __type__: {object: object$1}
    },
    right: {
      visible: {'boolean': bool$1},
      position: {string:['top-right','bottom-right','top-left','bottom-left']},
      __type__: {object: object$1}
    },
    __type__: {object: object$1,'boolean': bool$1}
  },
  groups: {
    visibility: {any: any$1},
    __type__: {object: object$1}
  },

  autoResize: {'boolean': bool$1},
  throttleRedraw: {number: number$1}, // TODO: DEPRICATED see https://github.com/almende/vis/issues/2511
  clickToUse: {'boolean': bool$1},
  end: {number: number$1, date: date$1, string: string$1, moment: moment$2},
  format: {
    minorLabels: {
      millisecond: {string: string$1,'undefined': 'undefined'},
      second: {string: string$1,'undefined': 'undefined'},
      minute: {string: string$1,'undefined': 'undefined'},
      hour: {string: string$1,'undefined': 'undefined'},
      weekday: {string: string$1,'undefined': 'undefined'},
      day: {string: string$1,'undefined': 'undefined'},
      week: {string: string$1,'undefined': 'undefined'},
      month: {string: string$1,'undefined': 'undefined'},
      quarter: {string: string$1,'undefined': 'undefined'},
      year: {string: string$1,'undefined': 'undefined'},
      __type__: {object: object$1}
    },
    majorLabels: {
      millisecond: {string: string$1,'undefined': 'undefined'},
      second: {string: string$1,'undefined': 'undefined'},
      minute: {string: string$1,'undefined': 'undefined'},
      hour: {string: string$1,'undefined': 'undefined'},
      weekday: {string: string$1,'undefined': 'undefined'},
      day: {string: string$1,'undefined': 'undefined'},
      week: {string: string$1,'undefined': 'undefined'},
      month: {string: string$1,'undefined': 'undefined'},
      quarter: {string: string$1,'undefined': 'undefined'},
      year: {string: string$1,'undefined': 'undefined'},
      __type__: {object: object$1}
    },
    __type__: {object: object$1}
  },
  moment: {'function': 'function'},
  height: {string: string$1, number: number$1},
  hiddenDates: {
    start: {date: date$1, number: number$1, string: string$1, moment: moment$2},
    end: {date: date$1, number: number$1, string: string$1, moment: moment$2},
    repeat: {string: string$1},
    __type__: {object: object$1, array: array$1}
  },
  locale:{string: string$1},
  locales:{
    __any__: {any: any$1},
    __type__: {object: object$1}
  },
  max: {date: date$1, number: number$1, string: string$1, moment: moment$2},
  maxHeight: {number: number$1, string: string$1},
  maxMinorChars: {number: number$1},
  min: {date: date$1, number: number$1, string: string$1, moment: moment$2},
  minHeight: {number: number$1, string: string$1},
  moveable: {'boolean': bool$1},
  multiselect: {'boolean': bool$1},
  orientation: {string: string$1},
  showCurrentTime: {'boolean': bool$1},
  showMajorLabels: {'boolean': bool$1},
  showMinorLabels: {'boolean': bool$1},
  showWeekScale: {'boolean': bool$1},
  snap: {'function': 'function', 'null': 'null'},
  start: {date: date$1, number: number$1, string: string$1, moment: moment$2},
  timeAxis: {
    scale: {string: string$1,'undefined': 'undefined'},
    step: {number: number$1,'undefined': 'undefined'},
    __type__: {object: object$1}
  },
  width: {string: string$1, number: number$1},
  zoomable: {'boolean': bool$1},
  zoomKey: {string: ['ctrlKey', 'altKey', 'metaKey', '']},
  zoomMax: {number: number$1},
  zoomMin: {number: number$1},
  zIndex: {number: number$1},
  __type__: {object: object$1}
};

let configureOptions$1 = {
  global: {
    alignCurrentTime: ['none', 'year', 'month', 'quarter', 'week', 'isoWeek', 'day', 'date', 'hour', 'minute', 'second'],   
    //yAxisOrientation: ['left','right'], // TDOO: enable as soon as Grahp2d doesn't crash when changing this on the fly
    sort: true,
    sampling: true,
    stack:false,
    shaded: {
      enabled: false,
      orientation: ['zero','top','bottom','group'] // zero, top, bottom
    },
    style: ['line','bar','points'], // line, bar
    barChart: {
      width: [50,5,100,5],
      minWidth: [50,5,100,5],
      sideBySide: false,
      align: ['left','center','right'] // left, center, right
    },
    interpolation: {
      enabled: true,
      parametrization: ['centripetal','chordal','uniform'] // uniform (alpha = 0.0), chordal (alpha = 1.0), centripetal (alpha = 0.5)
    },
    drawPoints: {
      enabled: true,
      size: [6,2,30,1],
      style: ['square', 'circle'] // square, circle
    },
    dataAxis: {
      showMinorLabels: true,
      showMajorLabels: true,
      showWeekScale: false,
      icons: false,
      width: [40,0,200,1],
      visible: true,
      alignZeros: true,
      left:{
        //range: {min:'undefined': 'undefined'ined,max:'undefined': 'undefined'ined},
        //format: function (value) {return value;},
        title: {text:'',style:''}
      },
      right:{
        //range: {min:'undefined': 'undefined'ined,max:'undefined': 'undefined'ined},
        //format: function (value) {return value;},
        title: {text:'',style:''}
      }
    },
    legend: {
      enabled: false,
      icons: true,
      left: {
        visible: true,
        position: ['top-right','bottom-right','top-left','bottom-left'] // top/bottom - left,right
      },
      right: {
        visible: true,
        position: ['top-right','bottom-right','top-left','bottom-left'] // top/bottom - left,right
      }
    },

    autoResize: true,
    clickToUse: false,
    end: '',
    format: {
      minorLabels: {
        millisecond:'SSS',
        second:     's',
        minute:     'HH:mm',
        hour:       'HH:mm',
        weekday:    'ddd D',
        day:        'D',
        week:       'w',
        month:      'MMM',
        quarter:    '[Q]Q',
        year:       'YYYY'
      },
      majorLabels: {
        millisecond:'HH:mm:ss',
        second:     'D MMMM HH:mm',
        minute:     'ddd D MMMM',
        hour:       'ddd D MMMM',
        weekday:    'MMMM YYYY',
        day:        'MMMM YYYY',
        week:       'MMMM YYYY',
        month:      'YYYY',
        quarter:    'YYYY',
        year:       ''
      }
    },

    height: '',
    locale: '',
    max: '',
    maxHeight: '',
    maxMinorChars: [7, 0, 20, 1],
    min: '',
    minHeight: '',
    moveable:true,
    orientation: ['both', 'bottom', 'top'],
    showCurrentTime: false,
    showMajorLabels: true,
    showMinorLabels: true,
    showWeekScale: false,
    start: '',
    width: '100%',
    zoomable: true,
    zoomKey: ['ctrlKey', 'altKey', 'metaKey', ''],
    zoomMax: [315360000000000, 10, 315360000000000, 1],
    zoomMin: [10, 10, 315360000000000, 1],
    zIndex: 0
  }
};

/**
 * Create a timeline visualization
 * @param {HTMLElement} container
 * @param {vis.DataSet | Array} [items]
 * @param {vis.DataSet | Array | vis.DataView | Object} [groups]
 * @param {Object} [options]  See Graph2d.setOptions for the available options.
 * @constructor Graph2d
 * @extends Core
 */
function Graph2d (container, items, groups, options) {
  // if the third element is options, the forth is groups (optionally);
  if (!(Array.isArray(groups) || isDataViewLike("id", groups)) && groups instanceof Object) {
    var forthArgument = options;
    options = groups;
    groups = forthArgument;
  }

  // TODO: REMOVE THIS in the next MAJOR release
  // see https://github.com/almende/vis/issues/2511
  if (options && options.throttleRedraw) {
    console.warn("Graph2d option \"throttleRedraw\" is DEPRICATED and no longer supported. It will be removed in the next MAJOR release.");
  }

  var me = this;
  this.defaultOptions = {
    start: null,
    end:   null,

    autoResize: true,

    orientation: {
      axis: 'bottom',   // axis orientation: 'bottom', 'top', or 'both'
      item: 'bottom'    // not relevant for Graph2d
    },

    moment: moment$1,

    width: null,
    height: null,
    maxHeight: null,
    minHeight: null
  };
  this.options = util$3.deepExtend({}, this.defaultOptions);

  // Create the DOM, props, and emitter
  this._create(container);

  // all components listed here will be repainted automatically
  this.components = [];

  this.body = {
    dom: this.dom,
    domProps: this.props,
    emitter: {
      on: this.on.bind(this),
      off: this.off.bind(this),
      emit: this.emit.bind(this)
    },
    hiddenDates: [],
    util: {
      getScale() {
        return me.timeAxis.step.scale;
      },
      getStep() {
        return me.timeAxis.step.step;
      },

      toScreen: me._toScreen.bind(me),
      toGlobalScreen: me._toGlobalScreen.bind(me), // this refers to the root.width
      toTime: me._toTime.bind(me),
      toGlobalTime : me._toGlobalTime.bind(me)
    }
  };

  // range
  this.range = new Range(this.body);
  this.components.push(this.range);
  this.body.range = this.range;

  // time axis
  this.timeAxis = new TimeAxis(this.body);
  this.components.push(this.timeAxis);
  //this.body.util.snap = this.timeAxis.snap.bind(this.timeAxis);

  // current time bar
  this.currentTime = new CurrentTime(this.body);
  this.components.push(this.currentTime);

  // item set
  this.linegraph = new LineGraph(this.body);

  this.components.push(this.linegraph);

  this.itemsData = null;      // DataSet
  this.groupsData = null;     // DataSet


  this.on('tap', function (event) {
    me.emit('click', me.getEventProperties(event));
  });
  this.on('doubletap', function (event) {
    me.emit('doubleClick', me.getEventProperties(event));
  });
  this.dom.root.oncontextmenu = function (event) {
    me.emit('contextmenu', me.getEventProperties(event));
  };
  
  //Single time autoscale/fit
  this.initialFitDone = false;
  this.on('changed', function (){
    if (me.itemsData == null) return;
    if (!me.initialFitDone && !me.options.rollingMode) {
      me.initialFitDone = true;
      if (me.options.start != undefined || me.options.end != undefined) {
        if (me.options.start == undefined || me.options.end == undefined) {
          var range = me.getItemRange();
        }

        var start = me.options.start != undefined ? me.options.start : range.min;
        var end   = me.options.end   != undefined ? me.options.end   : range.max;
        me.setWindow(start, end, {animation: false});
      } else {
        me.fit({animation: false});
      }
    }

    if (!me.initialDrawDone && (me.initialRangeChangeDone || (!me.options.start && !me.options.end) 
      || me.options.rollingMode)) {
      me.initialDrawDone = true;
      me.dom.root.style.visibility = 'visible';
      me.dom.loadingScreen.parentNode.removeChild(me.dom.loadingScreen);
      if (me.options.onInitialDrawComplete) {
        setTimeout(() => {
          return me.options.onInitialDrawComplete();
        }, 0);
      }
    }
  });
  
  // apply options
  if (options) {
    this.setOptions(options);
  }

  // IMPORTANT: THIS HAPPENS BEFORE SET ITEMS!
  if (groups) {
    this.setGroups(groups);
  }

  // create itemset
  if (items) {
    this.setItems(items);
  }

  // draw for the first time
  this._redraw();
}

// Extend the functionality from Core
Graph2d.prototype = new Core();

Graph2d.prototype.setOptions = function (options) {
  // validate options
  let errorFound = Validator$2.validate(options, allOptions$2);
  if (errorFound === true) {
    console.log('%cErrors have been found in the supplied options object.', printStyle);
  }

  Core.prototype.setOptions.call(this, options);
};

/**
 * Set items
 * @param {vis.DataSet | Array | null} items
 */
Graph2d.prototype.setItems = function(items) {
  var initialLoad = (this.itemsData == null);

  // convert to type DataSet when needed
  var newDataSet;
  if (!items) {
    newDataSet = null;
  }
  else if (isDataViewLike("id", newDataSet)) {
    newDataSet = typeCoerceDataSet(items);
  }
  else {
    // turn an array into a dataset
    newDataSet = typeCoerceDataSet(new DataSet(items));
  }

  // set items
  if (this.itemsData) {
    // stop maintaining a coerced version of the old data set
    this.itemsData.dispose();
  }
  this.itemsData = newDataSet;
  this.linegraph && this.linegraph.setItems(newDataSet != null ? newDataSet.rawDS : null);

  if (initialLoad) {
    if (this.options.start != undefined || this.options.end != undefined) {
      var start = this.options.start != undefined ? this.options.start : null;
      var end   = this.options.end != undefined   ? this.options.end : null;
      this.setWindow(start, end, {animation: false});
    }
    else {
      this.fit({animation: false});
    }
  }
};

/**
 * Set groups
 * @param {vis.DataSet | Array} groups
 */
Graph2d.prototype.setGroups = function(groups) {
  // convert to type DataSet when needed
  var newDataSet;
  if (!groups) {
    newDataSet = null;
  }
  else if (isDataViewLike("id", groups)) {
    newDataSet = groups;
  }
  else {
    // turn an array into a dataset
    newDataSet = new DataSet(groups);
  }

  this.groupsData = newDataSet;
  this.linegraph.setGroups(newDataSet);
};

/**
 * Returns an object containing an SVG element with the icon of the group (size determined by iconWidth and iconHeight), the label of the group (content) and the yAxisOrientation of the group (left or right).
 * @param {vis.GraphGroup.id} groupId
 * @param {number} width
 * @param {number} height
 * @returns {{icon: SVGElement, label: string, orientation: string}|string}
 */
Graph2d.prototype.getLegend = function(groupId, width, height) {
  if (width  === undefined) {width  = 15;}
  if (height === undefined) {height = 15;}
  if (this.linegraph.groups[groupId] !== undefined) {
    return this.linegraph.groups[groupId].getLegend(width,height);
  }
  else {
    return "cannot find group:'" +  groupId + "'";
  }
};

/**
 * This checks if the visible option of the supplied group (by ID) is true or false.
 * @param {vis.GraphGroup.id} groupId
 * @returns {boolean}
 */
Graph2d.prototype.isGroupVisible = function(groupId) {
  if (this.linegraph.groups[groupId] !== undefined) {
    return (this.linegraph.groups[groupId].visible && (this.linegraph.options.groups.visibility[groupId] === undefined || this.linegraph.options.groups.visibility[groupId] == true));
  }
  else {
    return false;
  }
};


/**
 * Get the data range of the item set.
 * @returns {{min: Date, max: Date}} range  A range with a start and end Date.
 *                                          When no minimum is found, min==null
 *                                          When no maximum is found, max==null
 */
Graph2d.prototype.getDataRange = function() {
  var min = null;
  var max = null;

  // calculate min from start filed
  for (var groupId in this.linegraph.groups) {
    if (this.linegraph.groups.hasOwnProperty(groupId)) {
      if (this.linegraph.groups[groupId].visible == true) {
        for (var i = 0; i < this.linegraph.groups[groupId].itemsData.length; i++) {
          var item = this.linegraph.groups[groupId].itemsData[i];
          var value = util$3.convert(item.x, 'Date').valueOf();
          min = min == null ? value : min > value ? value : min;
          max = max == null ? value : max < value ? value : max;
        }
      }
    }
  }

  return {
    min: (min != null) ? new Date(min) : null,
    max: (max != null) ? new Date(max) : null
  };
};


/**
 * Generate Timeline related information from an event
 * @param {Event} event
 * @return {Object} An object with related information, like on which area
 *                  The event happened, whether clicked on an item, etc.
 */
Graph2d.prototype.getEventProperties = function (event) {
  var clientX = event.center ? event.center.x : event.clientX;
  var clientY = event.center ? event.center.y : event.clientY;
  var x = clientX - util$3.getAbsoluteLeft(this.dom.centerContainer);
  var y = clientY - util$3.getAbsoluteTop(this.dom.centerContainer);
  var time = this._toTime(x);

  var customTime = CustomTime.customTimeFromTarget(event);

  var element = util$3.getTarget(event);
  var what = null;
  if (util$3.hasParent(element, this.timeAxis.dom.foreground))              {what = 'axis';}
  else if (this.timeAxis2 && util$3.hasParent(element, this.timeAxis2.dom.foreground)) {what = 'axis';}
  else if (util$3.hasParent(element, this.linegraph.yAxisLeft.dom.frame))   {what = 'data-axis';}
  else if (util$3.hasParent(element, this.linegraph.yAxisRight.dom.frame))  {what = 'data-axis';}
  else if (util$3.hasParent(element, this.linegraph.legendLeft.dom.frame))  {what = 'legend';}
  else if (util$3.hasParent(element, this.linegraph.legendRight.dom.frame)) {what = 'legend';}
  else if (customTime != null)                {what = 'custom-time';}
  else if (util$3.hasParent(element, this.currentTime.bar))                 {what = 'current-time';}
  else if (util$3.hasParent(element, this.dom.center))                      {what = 'background';}

  var value = [];
  var yAxisLeft = this.linegraph.yAxisLeft;
  var yAxisRight = this.linegraph.yAxisRight;
  if (!yAxisLeft.hidden && this.itemsData.length > 0) {
    value.push(yAxisLeft.screenToValue(y));
  }
  if (!yAxisRight.hidden && this.itemsData.length > 0) {
    value.push(yAxisRight.screenToValue(y));
  }

  return {
    event: event,
    customTime: customTime ? customTime.options.id : null,
    what: what,
    pageX: event.srcEvent ? event.srcEvent.pageX : event.pageX,
    pageY: event.srcEvent ? event.srcEvent.pageY : event.pageY,
    x: x,
    y: y,
    time: time,
    value: value
  }
};

/**
 * Load a configurator
 * @return {Object}
 * @private
 */
Graph2d.prototype._createConfigurator = function () {
  return new Configurator$2(this, this.dom.container, configureOptions$1);
};

// Locales have to be supplied by the user.
const defaultLanguage = getNavigatorLanguage();
moment.locale(defaultLanguage);

var visData_min = createCommonjsModule(function (module, exports) {
/**
 * vis-data
 * http://visjs.org/
 *
 * Manage unstructured data using DataSet. Add, update, and remove data, and listen for changes in the data.
 *
 * @version 7.1.2
 * @date    2021-01-08T20:37:11.601Z
 *
 * @copyright (c) 2011-2017 Almende B.V, http://almende.com
 * @copyright (c) 2017-2019 visjs contributors, https://github.com/visjs
 *
 * @license
 * vis.js is dual licensed under both
 *
 *   1. The Apache 2.0 License
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *   and
 *
 *   2. The MIT License
 *      http://opensource.org/licenses/MIT
 *
 * vis.js may be distributed under either license.
 */
!function(t,e){e(exports);}(commonjsGlobal,(function(t){var e="undefined"!=typeof globalThis?globalThis:"undefined"!=typeof window?window:"undefined"!=typeof commonjsGlobal?commonjsGlobal:"undefined"!=typeof self?self:{};function r(t){var e={exports:{}};return t(e,e.exports),e.exports}var n=function(t){return t&&t.Math==Math&&t},i=n("object"==typeof globalThis&&globalThis)||n("object"==typeof window&&window)||n("object"==typeof self&&self)||n("object"==typeof e&&e)||function(){return this}()||Function("return this")(),o=function(t){try{return !!t()}catch(t){return !0}},a=!o((function(){return 7!=Object.defineProperty({},1,{get:function(){return 7}})[1]})),u={}.propertyIsEnumerable,s=Object.getOwnPropertyDescriptor,c={f:s&&!u.call({1:2},1)?function(t){var e=s(this,t);return !!e&&e.enumerable}:u},f=function(t,e){return {enumerable:!(1&t),configurable:!(2&t),writable:!(4&t),value:e}},l={}.toString,h=function(t){return l.call(t).slice(8,-1)},p="".split,v=o((function(){return !Object("z").propertyIsEnumerable(0)}))?function(t){return "String"==h(t)?p.call(t,""):Object(t)}:Object,d=function(t){if(null==t)throw TypeError("Can't call method on "+t);return t},y=function(t){return v(d(t))},g=function(t){return "object"==typeof t?null!==t:"function"==typeof t},m=function(t,e){if(!g(t))return t;var r,n;if(e&&"function"==typeof(r=t.toString)&&!g(n=r.call(t)))return n;if("function"==typeof(r=t.valueOf)&&!g(n=r.call(t)))return n;if(!e&&"function"==typeof(r=t.toString)&&!g(n=r.call(t)))return n;throw TypeError("Can't convert object to primitive value")},b={}.hasOwnProperty,_=function(t,e){return b.call(t,e)},w=i.document,E=g(w)&&g(w.createElement),O=function(t){return E?w.createElement(t):{}},T=!a&&!o((function(){return 7!=Object.defineProperty(O("div"),"a",{get:function(){return 7}}).a})),S=Object.getOwnPropertyDescriptor,x={f:a?S:function(t,e){if(t=y(t),e=m(e,!0),T)try{return S(t,e)}catch(t){}if(_(t,e))return f(!c.f.call(t,e),t[e])}},k=/#|\.prototype\./,A=function(t,e){var r=I[j(t)];return r==D||r!=P&&("function"==typeof e?o(e):!!e)},j=A.normalize=function(t){return String(t).replace(k,".").toLowerCase()},I=A.data={},P=A.NATIVE="N",D=A.POLYFILL="P",L=A,C={},R=function(t){if("function"!=typeof t)throw TypeError(String(t)+" is not a function");return t},M=function(t,e,r){if(R(t),void 0===e)return t;switch(r){case 0:return function(){return t.call(e)};case 1:return function(r){return t.call(e,r)};case 2:return function(r,n){return t.call(e,r,n)};case 3:return function(r,n,i){return t.call(e,r,n,i)}}return function(){return t.apply(e,arguments)}},N=function(t){if(!g(t))throw TypeError(String(t)+" is not an object");return t},F=Object.defineProperty,z={f:a?F:function(t,e,r){if(N(t),e=m(e,!0),N(r),T)try{return F(t,e,r)}catch(t){}if("get"in r||"set"in r)throw TypeError("Accessors not supported");return "value"in r&&(t[e]=r.value),t}},q=a?function(t,e,r){return z.f(t,e,f(1,r))}:function(t,e,r){return t[e]=r,t},Y=x.f,U=function(t){var e=function(e,r,n){if(this instanceof t){switch(arguments.length){case 0:return new t;case 1:return new t(e);case 2:return new t(e,r)}return new t(e,r,n)}return t.apply(this,arguments)};return e.prototype=t.prototype,e},X=function(t,e){var r,n,o,a,u,s,c,f,l=t.target,h=t.global,p=t.stat,v=t.proto,d=h?i:p?i[l]:(i[l]||{}).prototype,y=h?C:C[l]||(C[l]={}),g=y.prototype;for(o in e)r=!L(h?o:l+(p?".":"#")+o,t.forced)&&d&&_(d,o),u=y[o],r&&(s=t.noTargetGet?(f=Y(d,o))&&f.value:d[o]),a=r&&s?s:e[o],r&&typeof u==typeof a||(c=t.bind&&r?M(a,i):t.wrap&&r?U(a):v&&"function"==typeof a?M(Function.call,a):a,(t.sham||a&&a.sham||u&&u.sham)&&q(c,"sham",!0),y[o]=c,v&&(_(C,n=l+"Prototype")||q(C,n,{}),C[n][o]=a,t.real&&g&&!g[o]&&q(g,o,a)));},V=Array.isArray||function(t){return "Array"==h(t)},W=Math.ceil,G=Math.floor,H=function(t){return isNaN(t=+t)?0:(t>0?G:W)(t)},$=Math.min,J=function(t){return t>0?$(H(t),9007199254740991):0},Q=function(t,e,r,n,i,o,a,u){for(var s,c=i,f=0,l=!!a&&M(a,u,3);f<n;){if(f in r){if(s=l?l(r[f],f,e):r[f],o>0&&V(s))c=Q(t,e,s,J(s.length),c,o-1)-1;else {if(c>=9007199254740991)throw TypeError("Exceed the acceptable arra
/*! Hammer.JS - v2.0.17-rc - 2019-12-16
	 * http://naver.github.io/egjs
	 *
	 * Forked By Naver egjs
	 * Copyright (c) hammerjs
	 * Licensed under the MIT license */
function ia(){return (ia=Object.assign||function(t){for(var e=1;e<arguments.length;e++){var r=arguments[e];for(var n in r)Object.prototype.hasOwnProperty.call(r,n)&&(t[n]=r[n]);}return t}).apply(this,arguments)}function oa(t,e){t.prototype=Object.create(e.prototype),t.prototype.constructor=t,t.__proto__=e;}function aa(t){if(void 0===t)throw new ReferenceError("this hasn't been initialised - super() hasn't been called");return t}var ua,sa="function"!=typeof Object.assign?function(t){if(null==t)throw new TypeError("Cannot convert undefined or null to object");for(var e=Object(t),r=1;r<arguments.length;r++){var n=arguments[r];if(null!=n)for(var i in n)n.hasOwnProperty(i)&&(e[i]=n[i]);}return e}:Object.assign,ca=["","webkit","Moz","MS","ms","o"],fa="undefined"==typeof document?{style:{}}:document.createElement("div"),la=Math.round,ha=Math.abs,pa=Date.now;function va(t,e){for(var r,n,i=e[0].toUpperCase()+e.slice(1),o=0;o<ca.length;){if((n=(r=ca[o])?r+i:e)in t)return n;o++;}}ua="undefined"==typeof window?{}:window;var da=va(fa.style,"touchAction"),ya=void 0!==da;var ga="compute",ma="auto",ba="manipulation",_a="none",wa="pan-x",Ea="pan-y",Oa=function(){if(!ya)return !1;var t={},e=ua.CSS&&ua.CSS.supports;return ["auto","manipulation","pan-y","pan-x","pan-x pan-y","none"].forEach((function(r){return t[r]=!e||ua.CSS.supports("touch-action",r)})),t}(),Ta="ontouchstart"in ua,Sa=void 0!==va(ua,"PointerEvent"),xa=Ta&&/mobile|tablet|ip(ad|hone|od)|android/i.test(navigator.userAgent),ka="touch",Aa="mouse",ja=16,Ia=24,Pa=["x","y"],Da=["clientX","clientY"];function La(t,e,r){var n;if(t)if(t.forEach)t.forEach(e,r);else if(void 0!==t.length)for(n=0;n<t.length;)e.call(r,t[n],n,t),n++;else for(n in t)t.hasOwnProperty(n)&&e.call(r,t[n],n,t);}function Ca(t,e){return "function"==typeof t?t.apply(e&&e[0]||void 0,e):t}function Ra(t,e){return t.indexOf(e)>-1}var Ma=function(){function t(t,e){this.manager=t,this.set(e);}var e=t.prototype;return e.set=function(t){t===ga&&(t=this.compute()),ya&&this.manager.element.style&&Oa[t]&&(this.manager.element.style[da]=t),this.actions=t.toLowerCase().trim();},e.update=function(){this.set(this.manager.options.touchAction);},e.compute=function(){var t=[];return La(this.manager.recognizers,(function(e){Ca(e.options.enable,[e])&&(t=t.concat(e.getTouchAction()));})),function(t){if(Ra(t,_a))return _a;var e=Ra(t,wa),r=Ra(t,Ea);return e&&r?_a:e||r?e?wa:Ea:Ra(t,ba)?ba:ma}(t.join(" "))},e.preventDefaults=function(t){var e=t.srcEvent,r=t.offsetDirection;if(this.manager.session.prevented)e.preventDefault();else {var n=this.actions,i=Ra(n,_a)&&!Oa.none,o=Ra(n,Ea)&&!Oa["pan-y"],a=Ra(n,wa)&&!Oa["pan-x"];if(i){var u=1===t.pointers.length,s=t.distance<2,c=t.deltaTime<250;if(u&&s&&c)return}if(!a||!o)return i||o&&6&r||a&&r&Ia?this.preventSrc(e):void 0}},e.preventSrc=function(t){this.manager.session.prevented=!0,t.preventDefault();},t}();function Na(t,e){for(;t;){if(t===e)return !0;t=t.parentNode;}return !1}function Fa(t){var e=t.length;if(1===e)return {x:la(t[0].clientX),y:la(t[0].clientY)};for(var r=0,n=0,i=0;i<e;)r+=t[i].clientX,n+=t[i].clientY,i++;return {x:la(r/e),y:la(n/e)}}function za(t){for(var e=[],r=0;r<t.pointers.length;)e[r]={clientX:la(t.pointers[r].clientX),clientY:la(t.pointers[r].clientY)},r++;return {timeStamp:pa(),pointers:e,center:Fa(e),deltaX:t.deltaX,deltaY:t.deltaY}}function qa(t,e,r){r||(r=Pa);var n=e[r[0]]-t[r[0]],i=e[r[1]]-t[r[1]];return Math.sqrt(n*n+i*i)}function Ya(t,e,r){r||(r=Pa);var n=e[r[0]]-t[r[0]],i=e[r[1]]-t[r[1]];return 180*Math.atan2(i,n)/Math.PI}function Ua(t,e){return t===e?1:ha(t)>=ha(e)?t<0?2:4:e<0?8:ja}function Xa(t,e,r){return {x:e/t||0,y:r/t||0}}function Va(t,e){var r=t.session,n=e.pointers,i=n.length;r.firstInput||(r.firstInput=za(e)),i>1&&!r.firstMultiple?r.firstMultiple=za(e):1===i&&(r.firstMultiple=!1);var o=r.firstInput,a=r.firstMultiple,u=a?a.center:o.center,s=e.center=Fa(n);e.timeStamp=pa(),e.deltaTime=e.timeStamp-o.timeStamp,e.angle=Ya(u,s),e.distance=qa(u,s),function(t,e){var r=e.center,n=t.offsetDelta||{},i=t.prevDelta||{},o=t.prevInput||{};1!==e.eventType&&4!==o.eventType||(

});

var e=[],t=[];function n(n,r){if(n&&"undefined"!=typeof document){var a,s=!0===r.prepend?"prepend":"append",d=!0===r.singleTag,i="string"==typeof r.container?document.querySelector(r.container):document.getElementsByTagName("head")[0];if(d){var u=e.indexOf(i);-1===u&&(u=e.push(i)-1,t[u]={}),a=t[u]&&t[u][s]?t[u][s]:t[u][s]=c();}else a=c();65279===n.charCodeAt(0)&&(n=n.substring(1)),a.styleSheet?a.styleSheet.cssText+=n:a.appendChild(document.createTextNode(n));}function c(){var e=document.createElement("style");if(e.setAttribute("type","text/css"),r.attributes)for(var t=Object.keys(r.attributes),n=0;n<t.length;n++)e.setAttribute(t[n],r.attributes[t[n]]);var a="prepend"===s?"afterbegin":"beforeend";return i.insertAdjacentElement(a,e),e}}

var css$1 = ".vis-time-axis {\n  position: relative;\n  overflow: hidden;\n}\n\n.vis-time-axis.vis-foreground {\n  top: 0;\n  left: 0;\n  width: 100%;\n}\n\n.vis-time-axis.vis-background {\n  position: absolute;\n  top: 0;\n  left: 0;\n  width: 100%;\n  height: 100%;\n}\n\n.vis-time-axis .vis-text {\n  position: absolute;\n  color: #4d4d4d;\n  padding: 3px;\n  overflow: hidden;\n  box-sizing: border-box;\n\n  white-space: nowrap;\n}\n\n.vis-time-axis .vis-text.vis-measure {\n  position: absolute;\n  padding-left: 0;\n  padding-right: 0;\n  margin-left: 0;\n  margin-right: 0;\n  visibility: hidden;\n}\n\n.vis-time-axis .vis-grid.vis-vertical {\n  position: absolute;\n  border-left: 1px solid;\n}\n\n.vis-time-axis .vis-grid.vis-vertical-rtl {\n  position: absolute;\n  border-right: 1px solid;\n}\n\n.vis-time-axis .vis-grid.vis-minor {\n  border-color: #e5e5e5;\n}\n\n.vis-time-axis .vis-grid.vis-major {\n  border-color: #bfbfbf;\n}\n\n.vis .overlay {\n  position: absolute;\n  top: 0;\n  left: 0;\n  width: 100%;\n  height: 100%;\n\n  /* Must be displayed above for example selected Timeline items */\n  z-index: 10;\n}\n\n.vis-active {\n  box-shadow: 0 0 10px #86d5f8;\n}\n\n.vis-custom-time {\n  background-color: #6E94FF;\n  width: 2px;\n  cursor: move;\n  z-index: 1;\n}\n\n.vis-custom-time > .vis-custom-time-marker {\n  background-color: inherit;\n  color: white;\n  font-size: 12px;\n  white-space: nowrap;\n  padding: 3px 5px;\n  top: 0px;\n  cursor: initial;\n  z-index: inherit;\n}\n.vis-timeline {\n  /*\n  -webkit-transition: height .4s ease-in-out;\n  transition:         height .4s ease-in-out;\n  */\n}\n\n.vis-panel {\n  /*\n  -webkit-transition: height .4s ease-in-out, top .4s ease-in-out;\n  transition:         height .4s ease-in-out, top .4s ease-in-out;\n  */\n}\n\n.vis-axis {\n  /*\n  -webkit-transition: top .4s ease-in-out;\n  transition:         top .4s ease-in-out;\n  */\n}\n\n/* TODO: get animation working nicely\n\n.vis-item {\n  -webkit-transition: top .4s ease-in-out;\n  transition:         top .4s ease-in-out;\n}\n\n.vis-item.line {\n  -webkit-transition: height .4s ease-in-out, top .4s ease-in-out;\n  transition:         height .4s ease-in-out, top .4s ease-in-out;\n}\n/**/\n.vis-current-time {\n  background-color: #FF7F6E;\n  width: 2px;\n  z-index: 1;\n  pointer-events: none;\n}\n\n.vis-rolling-mode-btn {\n  height: 40px;\n  width: 40px;\n  position: absolute;\n  top: 7px;\n  right: 20px;\n  border-radius: 50%;\n  font-size: 28px;\n  cursor: pointer;\n  opacity: 0.8;\n  color: white;\n  font-weight: bold;\n  text-align: center;\n  background: #3876c2;\n}\n.vis-rolling-mode-btn:before {\n  content: \"\\26F6\";\n}\n\n.vis-rolling-mode-btn:hover {\n  opacity: 1;\n}\n.vis-panel {\n  position: absolute;\n\n  padding: 0;\n  margin: 0;\n\n  box-sizing: border-box;\n}\n\n.vis-panel.vis-center,\n.vis-panel.vis-left,\n.vis-panel.vis-right,\n.vis-panel.vis-top,\n.vis-panel.vis-bottom {\n  border: 1px #bfbfbf;\n}\n\n.vis-panel.vis-center,\n.vis-panel.vis-left,\n.vis-panel.vis-right {\n  border-top-style: solid;\n  border-bottom-style: solid;\n  overflow: hidden;\n}\n\n.vis-left.vis-panel.vis-vertical-scroll, .vis-right.vis-panel.vis-vertical-scroll {\n  height: 100%;\n  overflow-x: hidden;\n  overflow-y: scroll;\n} \n\n.vis-left.vis-panel.vis-vertical-scroll {\n  direction: rtl;\n}\n\n.vis-left.vis-panel.vis-vertical-scroll .vis-content {\n  direction: ltr;\n}\n\n.vis-right.vis-panel.vis-vertical-scroll {\n  direction: ltr;\n}\n\n.vis-right.vis-panel.vis-vertical-scroll .vis-content {\n  direction: rtl;\n}\n\n.vis-panel.vis-center,\n.vis-panel.vis-top,\n.vis-panel.vis-bottom {\n  border-left-style: solid;\n  border-right-style: solid;\n}\n\n.vis-background {\n  overflow: hidden;\n}\n\n.vis-panel > .vis-content {\n  position: relative;\n}\n\n.vis-panel .vis-shadow {\n  position: absolute;\n  width: 100%;\n  height: 1px;\n  box-shadow: 0 0 10px rgba(0,0,0,0.8);\n  /* TODO: find a nice way to ensure vis-shadows are drawn on top of items\n  z-index: 1;\n  */\n}\n\n.vis-panel .vis-shadow.vis-top {\n  top: -1px;\n  left: 0
n(css$1,{});

function parseTag$2(tag, tagList) {
    tag = tag.trim();
    // Skip empty tags
    if (tag.length === 0) {
        return;
    }
    // Parse all subtags out of the given tag.
    // I.e., #hello/i/am would yield [#hello/i/am, #hello/i, #hello]. */
    tagList.push(tag);
    while (tag.contains("/")) {
        tag = tag.substring(0, tag.lastIndexOf("/"));
        tagList.push(tag);
    }
}
function FilterMDFiles(file, tagList, metadataCache) {
    if (!tagList || tagList.length === 0) {
        return true;
    }
    let tags = obsidian.getAllTags(metadataCache.getFileCache(file)).map(e => e.slice(1, e.length));
    if (tags && tags.length > 0) {
        let filetags = [];
        tags.forEach(tag => parseTag$2(tag, filetags));
        return tagList.every(val => { return filetags.indexOf(val) >= 0; });
    }
    return false;
}
/**
 * Create date of passed string
 * @date - string date in the format YYYY-MM-DD-HH
 */
function createDate(date) {
    var _a, _b, _c, _d;
    let dateComp = date.split(',');
    // cannot simply replace '-' as need to support negative years
    return new Date(+((_a = dateComp[0]) !== null && _a !== void 0 ? _a : 0), +((_b = dateComp[1]) !== null && _b !== void 0 ? _b : 0), +((_c = dateComp[2]) !== null && _c !== void 0 ? _c : 0), +((_d = dateComp[3]) !== null && _d !== void 0 ? _d : 0));
}
/**
 * Return URL for specified image path
 * @param path - image path
 */
function getImgUrl(vaultAdaptor, path) {
    if (!path) {
        return null;
    }
    let regex = new RegExp('^https:\/\/');
    if (path.match(regex)) {
        return path;
    }
    return vaultAdaptor.getResourcePath(path);
}

class TimelineProcessor {
    insertTimelineIntoCurrentNote(sourceView, settings, vaultFiles, fileCache, appVault) {
        return __awaiter(this, void 0, void 0, function* () {
            let editor = sourceView.sourceMode.cmEditor;
            if (editor) {
                const source = editor.getValue();
                let match = RENDER_TIMELINE.exec(source);
                if (match) {
                    let tagList = match[1];
                    let div = document.createElement('div');
                    let rendered = document.createElement('div');
                    rendered.addClass('timeline-rendered');
                    rendered.setText(new Date().toString());
                    div.appendChild(document.createComment(`TIMELINE BEGIN tags='${match[1]}'`));
                    yield this.run(tagList, div, settings, vaultFiles, fileCache, appVault, false);
                    div.appendChild(rendered);
                    div.appendChild(document.createComment('TIMELINE END'));
                    editor.setValue(source.replace(match[0], div.innerHTML));
                }
            }
        });
    }
    ;
    run(source, el, settings, vaultFiles, fileCache, appVault, visTimeline) {
        var _a, _b, _c, _d;
        return __awaiter(this, void 0, void 0, function* () {
            let args = {
                tags: '',
                divHeight: 400,
                startDate: '-1000',
                endDate: '3000',
                minDate: '-3000',
                maxDate: '3000'
            };
            // read arguments
            if (visTimeline) {
                source.split('\n').map(e => {
                    var _a;
                    e = e.trim();
                    if (e) {
                        let param = e.split('=');
                        if (param[1]) {
                            args[param[0]] = (_a = param[1]) === null || _a === void 0 ? void 0 : _a.trim();
                        }
                    }
                });
            }
            else {
                let lines = source.trim();
                // Parse the tags to search for the proper files
                args.tags = lines;
            }
            let tagList = [];
            args.tags.split(";").forEach(tag => parseTag$2(tag, tagList));
            tagList.push(settings.timelineTag);
            // Filter all markdown files to only those containing the tag list
            let fileList = vaultFiles.filter(file => FilterMDFiles(file, tagList, fileCache));
            if (!fileList) {
                // if no files valid for timeline
                return;
            }
            // Keep only the files that have the time info
            let timeline = document.createElement('div');
            timeline.setAttribute('class', 'timeline');
            let timelineNotes = [];
            let timelineDates = [];
            for (let file of fileList) {
                // Create a DOM Parser
                const domparser = new DOMParser();
                const doc = domparser.parseFromString(yield appVault.read(file), 'text/html');
                let timelineData = doc.getElementsByClassName('ob-timelines');
                for (let event of timelineData) {
                    if (!(event instanceof HTMLElement)) {
                        continue;
                    }
                    let noteId;
                    // check if a valid date is specified
                    if (event.dataset.date[0] == '-') {
                        // if it is a negative year
                        noteId = +event.dataset.date.substring(1, event.dataset.date.length).split('-').join('') * -1;
                    }
                    else {
                        noteId = +event.dataset.date.split('-').join('');
                    }
                    if (!Number.isInteger(noteId)) {
                        continue;
                    }
                    // if not title is specified use note name
                    let noteTitle = (_a = event.dataset.title) !== null && _a !== void 0 ? _a : file.name;
                    let noteClass = (_b = event.dataset.class) !== null && _b !== void 0 ? _b : "";
                    let notePath = '/' + file.path;
                    let type = (_c = event.dataset.type) !== null && _c !== void 0 ? _c : "";
                    let endDate = (_d = event.dataset.end) !== null && _d !== void 0 ? _d : null;
                    if (!timelineNotes[noteId]) {
                        timelineNotes[noteId] = [];
                        timelineNotes[noteId][0] = {
                            date: event.dataset.date,
                            title: noteTitle,
                            img: getImgUrl(appVault.adapter, event.dataset.img),
                            innerHTML: event.innerHTML,
                            path: notePath,
                            class: noteClass,
                            type: type,
                            endDate: endDate
                        };
                        timelineDates.push(noteId);
                    }
                    else {
                        // if note_id already present append to it
                        timelineNotes[noteId][timelineNotes[noteId].length] = {
                            date: event.dataset.date,
                            title: noteTitle,
                            img: getImgUrl(appVault.adapter, event.dataset.img),
                            innerHTML: event.innerHTML,
                            path: notePath,
                            class: noteClass,
                            type: type,
                            endDate: endDate
                        };
                    }
                }
            }
            // Sort events based on setting
            if (settings.sortDirection) {
                // default is ascending
                timelineDates = timelineDates.sort((d1, d2) => d1 - d2);
            }
            else {
                // else it is descending
                timelineDates = timelineDates.sort((d1, d2) => d2 - d1);
            }
            if (!visTimeline) {
                let eventCount = 0;
                // Build the timeline html element
                for (let date of timelineDates) {
                    let noteContainer = timeline.createDiv({ cls: 'timeline-container' });
                    let noteHeader = noteContainer.createEl('h2', { text: timelineNotes[date][0].date.replace(/-0*$/g, '').replace(/-0*$/g, '').replace(/-0*$/g, '') });
                    let eventContainer = noteContainer.createDiv({ cls: 'timeline-event-list', attr: { 'style': 'display: block' } });
                    noteHeader.addEventListener('click', event => {
                        if (eventContainer.style.getPropertyValue('display') === 'none') {
                            eventContainer.style.setProperty('display', 'block');
                            return;
                        }
                        eventContainer.style.setProperty('display', 'none');
                    });
                    if (eventCount % 2 == 0) {
                        // if its even add it to the left
                        noteContainer.addClass('timeline-left');
                    }
                    else {
                        // else add it to the right
                        noteContainer.addClass('timeline-right');
                        noteHeader.setAttribute('style', 'text-align: right;');
                    }
                    if (!timelineNotes[date]) {
                        continue;
                    }
                    for (let eventAtDate of timelineNotes[date]) {
                        let noteCard = eventContainer.createDiv({ cls: 'timeline-card' });
                        // add an image only if available
                        if (eventAtDate.img) {
                            noteCard.createDiv({ cls: 'thumb', attr: { style: `background-image: url(${eventAtDate.img});` } });
                        }
                        if (eventAtDate.class) {
                            noteCard.addClass(eventAtDate.class);
                        }
                        noteCard.createEl('article').createEl('h3').createEl('a', {
                            cls: 'internal-link',
                            attr: { href: `${eventAtDate.path}` },
                            text: eventAtDate.title
                        });
                        noteCard.createEl('p', { text: eventAtDate.innerHTML });
                    }
                    eventCount++;
                }
                // Replace the selected tags with the timeline html
                el.appendChild(timeline);
                return;
            }
            // Create a DataSet
            let items = new visData_min.DataSet([]);
            timelineDates.forEach(date => {
                // add all events at this date
                Object.values(timelineNotes[date]).forEach(event => {
                    var _a, _b, _c, _d;
                    // Create Event Card
                    let noteCard = document.createElement('div');
                    noteCard.className = 'timeline-card';
                    // add an image only if available
                    if (event.img) {
                        noteCard.createDiv({ cls: 'thumb', attr: { style: `background-image: url(${event.img});` } });
                    }
                    if (event.class) {
                        noteCard.addClass(event.class);
                    }
                    noteCard.createEl('article').createEl('h3').createEl('a', {
                        cls: 'internal-link',
                        attr: { href: `${event.path}` },
                        text: event.title
                    });
                    noteCard.createEl('p', { text: event.innerHTML });
                    let startDate = (_a = event.date) === null || _a === void 0 ? void 0 : _a.replace(/(.*)-\d*$/g, '$1');
                    let start, end;
                    if (startDate[0] == '-') {
                        // handle negative year
                        let startComp = startDate.substring(1, startDate.length).split('-');
                        start = new Date(+`-${startComp[0]}`, +startComp[1], +startComp[2]);
                    }
                    else {
                        start = new Date(startDate);
                    }
                    let endDate = (_b = event.endDate) === null || _b === void 0 ? void 0 : _b.replace(/(.*)-\d*$/g, '$1');
                    if (endDate && endDate[0] == '-') {
                        // handle negative year
                        let endComp = endDate.substring(1, endDate.length).split('-');
                        end = new Date(+`-${endComp[0]}`, +endComp[1], +endComp[2]);
                    }
                    else {
                        end = new Date(endDate);
                    }
                    if (start.toString() === 'Invalid Date') {
                        return;
                    }
                    if ((event.type === "range" || event.type === "background") && end.toString() === 'Invalid Date') {
                        return;
                    }
                    // Add Event data
                    items.add({
                        id: items.length + 1,
                        content: (_c = event.title) !== null && _c !== void 0 ? _c : '',
                        title: noteCard.outerHTML,
                        start: start,
                        className: (_d = event.class) !== null && _d !== void 0 ? _d : '',
                        type: event.type,
                        end: end !== null && end !== void 0 ? end : null
                    });
                });
            });
            // Configuration for the Timeline
            let options = {
                minHeight: +args.divHeight,
                showCurrentTime: false,
                showTooltips: false,
                template: function (item) {
                    let eventContainer = document.createElement('div');
                    eventContainer.setText(item.content);
                    let eventCard = eventContainer.createDiv();
                    eventCard.outerHTML = item.title;
                    eventContainer.addEventListener('click', event => {
                        let el = eventContainer.getElementsByClassName('timeline-card')[0];
                        el.style.setProperty('display', 'block');
                        el.style.setProperty('top', `-${el.clientHeight + 10}px`);
                    });
                    return eventContainer;
                },
                start: createDate(args.startDate),
                end: createDate(args.endDate),
                min: createDate(args.minDate),
                max: createDate(args.maxDate)
            };
            // Create a Timeline
            timeline.setAttribute('class', 'timeline-vis');
            new Timeline(timeline, items, options);
            // Replace the selected tags with the timeline html
            el.appendChild(timeline);
        });
    }
}

class TimelinesPlugin extends obsidian.Plugin {
    onload() {
        return __awaiter(this, void 0, void 0, function* () {
            // Load message
            yield this.loadSettings();
            console.log('Loaded Timelines Plugin');
            // Register timeline block renderer
            this.registerMarkdownCodeBlockProcessor('timeline', (source, el, ctx) => __awaiter(this, void 0, void 0, function* () {
                const proc = new TimelineProcessor();
                yield proc.run(source, el, this.settings, this.app.vault.getMarkdownFiles(), this.app.metadataCache, this.app.vault, false);
            }));
            // Register vis-timeline block renderer
            this.registerMarkdownCodeBlockProcessor('timeline-vis', (source, el, ctx) => __awaiter(this, void 0, void 0, function* () {
                const proc = new TimelineProcessor();
                yield proc.run(source, el, this.settings, this.app.vault.getMarkdownFiles(), this.app.metadataCache, this.app.vault, true);
            }));
            this.addCommand({
                id: "render-timeline",
                name: "Render Timeline",
                callback: () => __awaiter(this, void 0, void 0, function* () {
                    const proc = new TimelineProcessor();
                    let view = this.app.workspace.getActiveViewOfType(obsidian.MarkdownView);
                    if (view) {
                        yield proc.insertTimelineIntoCurrentNote(view, this.settings, this.app.vault.getMarkdownFiles(), this.app.metadataCache, this.app.vault);
                    }
                })
            });
            this.addSettingTab(new TimelinesSettingTab(this.app, this));
        });
    }
    onunload() {
        console.log('unloading plugin');
    }
    loadSettings() {
        return __awaiter(this, void 0, void 0, function* () {
            this.settings = Object.assign({}, DEFAULT_SETTINGS, yield this.loadData());
        });
    }
    saveSettings() {
        return __awaiter(this, void 0, void 0, function* () {
            yield this.saveData(this.settings);
        });
    }
}

module.exports = TimelinesPlugin;
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