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July 31, 2014 18:13
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| /** | |
| * This script gives you the zone info key representing your device's time zone setting. | |
| * | |
| * @name jsTimezoneDetect | |
| * @version 1.0.5 | |
| * @author Jon Nylander | |
| * @license MIT License - http://www.opensource.org/licenses/mit-license.php | |
| * | |
| * For usage and examples, visit: | |
| * http://pellepim.bitbucket.org/jstz/ | |
| * | |
| * Copyright (c) Jon Nylander | |
| */ | |
| /*jslint undef: true */ | |
| /*global console, exports*/ | |
| (function(root) { | |
| /** | |
| * Namespace to hold all the code for timezone detection. | |
| */ | |
| var jstz = (function () { | |
| 'use strict'; | |
| var HEMISPHERE_SOUTH = 's', | |
| /** | |
| * Gets the offset in minutes from UTC for a certain date. | |
| * @param {Date} date | |
| * @returns {Number} | |
| */ | |
| get_date_offset = function (date) { | |
| var offset = -date.getTimezoneOffset(); | |
| return (offset !== null ? offset : 0); | |
| }, | |
| get_date = function (year, month, date) { | |
| var d = new Date(); | |
| if (year !== undefined) { | |
| d.setFullYear(year); | |
| } | |
| d.setMonth(month); | |
| d.setDate(date); | |
| return d; | |
| }, | |
| get_january_offset = function (year) { | |
| return get_date_offset(get_date(year, 0 ,2)); | |
| }, | |
| get_june_offset = function (year) { | |
| return get_date_offset(get_date(year, 5, 2)); | |
| }, | |
| /** | |
| * Private method. | |
| * Checks whether a given date is in daylight saving time. | |
| * If the date supplied is after august, we assume that we're checking | |
| * for southern hemisphere DST. | |
| * @param {Date} date | |
| * @returns {Boolean} | |
| */ | |
| date_is_dst = function (date) { | |
| var is_southern = date.getMonth() > 7, | |
| base_offset = is_southern ? get_june_offset(date.getFullYear()) : | |
| get_january_offset(date.getFullYear()), | |
| date_offset = get_date_offset(date), | |
| is_west = base_offset < 0, | |
| dst_offset = base_offset - date_offset; | |
| if (!is_west && !is_southern) { | |
| return dst_offset < 0; | |
| } | |
| return dst_offset !== 0; | |
| }, | |
| /** | |
| * This function does some basic calculations to create information about | |
| * the user's timezone. It uses REFERENCE_YEAR as a solid year for which | |
| * the script has been tested rather than depend on the year set by the | |
| * client device. | |
| * | |
| * Returns a key that can be used to do lookups in jstz.olson.timezones. | |
| * eg: "720,1,2". | |
| * | |
| * @returns {String} | |
| */ | |
| lookup_key = function () { | |
| var january_offset = get_january_offset(), | |
| june_offset = get_june_offset(), | |
| diff = january_offset - june_offset; | |
| if (diff < 0) { | |
| return january_offset + ",1"; | |
| } else if (diff > 0) { | |
| return june_offset + ",1," + HEMISPHERE_SOUTH; | |
| } | |
| return january_offset + ",0"; | |
| }, | |
| /** | |
| * Uses get_timezone_info() to formulate a key to use in the olson.timezones dictionary. | |
| * | |
| * Returns a primitive object on the format: | |
| * {'timezone': TimeZone, 'key' : 'the key used to find the TimeZone object'} | |
| * | |
| * @returns Object | |
| */ | |
| determine = function () { | |
| var key = lookup_key(); | |
| return new jstz.TimeZone(jstz.olson.timezones[key]); | |
| }, | |
| /** | |
| * This object contains information on when daylight savings starts for | |
| * different timezones. | |
| * | |
| * The list is short for a reason. Often we do not have to be very specific | |
| * to single out the correct timezone. But when we do, this list comes in | |
| * handy. | |
| * | |
| * Each value is a date denoting when daylight savings starts for that timezone. | |
| */ | |
| dst_start_for = function (tz_name) { | |
| var ru_pre_dst_change = new Date(2010, 6, 15, 1, 0, 0, 0), // In 2010 Russia had DST, this allows us to detect Russia :) | |
| dst_starts = { | |
| 'America/Denver': new Date(2011, 2, 13, 3, 0, 0, 0), | |
| 'America/Mazatlan': new Date(2011, 3, 3, 3, 0, 0, 0), | |
| 'America/Chicago': new Date(2011, 2, 13, 3, 0, 0, 0), | |
| 'America/Mexico_City': new Date(2011, 3, 3, 3, 0, 0, 0), | |
| 'America/Asuncion': new Date(2012, 9, 7, 3, 0, 0, 0), | |
| 'America/Santiago': new Date(2012, 9, 3, 3, 0, 0, 0), | |
| 'America/Campo_Grande': new Date(2012, 9, 21, 5, 0, 0, 0), | |
| 'America/Montevideo': new Date(2011, 9, 2, 3, 0, 0, 0), | |
| 'America/Sao_Paulo': new Date(2011, 9, 16, 5, 0, 0, 0), | |
| 'America/Los_Angeles': new Date(2011, 2, 13, 8, 0, 0, 0), | |
| 'America/Santa_Isabel': new Date(2011, 3, 5, 8, 0, 0, 0), | |
| 'America/Havana': new Date(2012, 2, 10, 2, 0, 0, 0), | |
| 'America/New_York': new Date(2012, 2, 10, 7, 0, 0, 0), | |
| 'Europe/Helsinki': new Date(2013, 2, 31, 5, 0, 0, 0), | |
| 'Pacific/Auckland': new Date(2011, 8, 26, 7, 0, 0, 0), | |
| 'America/Halifax': new Date(2011, 2, 13, 6, 0, 0, 0), | |
| 'America/Goose_Bay': new Date(2011, 2, 13, 2, 1, 0, 0), | |
| 'America/Miquelon': new Date(2011, 2, 13, 5, 0, 0, 0), | |
| 'America/Godthab': new Date(2011, 2, 27, 1, 0, 0, 0), | |
| 'Europe/Moscow': ru_pre_dst_change, | |
| 'Asia/Amman': new Date(2013, 2, 29, 1, 0, 0, 0), | |
| 'Asia/Beirut': new Date(2013, 2, 31, 2, 0, 0, 0), | |
| 'Asia/Damascus': new Date(2013, 3, 6, 2, 0, 0, 0), | |
| 'Asia/Jerusalem': new Date(2013, 2, 29, 5, 0, 0, 0), | |
| 'Asia/Yekaterinburg': ru_pre_dst_change, | |
| 'Asia/Omsk': ru_pre_dst_change, | |
| 'Asia/Krasnoyarsk': ru_pre_dst_change, | |
| 'Asia/Irkutsk': ru_pre_dst_change, | |
| 'Asia/Yakutsk': ru_pre_dst_change, | |
| 'Asia/Vladivostok': ru_pre_dst_change, | |
| 'Asia/Baku': new Date(2013, 2, 31, 4, 0, 0), | |
| 'Asia/Yerevan': new Date(2013, 2, 31, 3, 0, 0), | |
| 'Asia/Kamchatka': ru_pre_dst_change, | |
| 'Asia/Gaza': new Date(2010, 2, 27, 4, 0, 0), | |
| 'Africa/Cairo': new Date(2010, 4, 1, 3, 0, 0), | |
| 'Europe/Minsk': ru_pre_dst_change, | |
| 'Pacific/Apia': new Date(2010, 10, 1, 1, 0, 0, 0), | |
| 'Pacific/Fiji': new Date(2010, 11, 1, 0, 0, 0), | |
| 'Australia/Perth': new Date(2008, 10, 1, 1, 0, 0, 0) | |
| }; | |
| return dst_starts[tz_name]; | |
| }; | |
| return { | |
| determine: determine, | |
| date_is_dst: date_is_dst, | |
| dst_start_for: dst_start_for | |
| }; | |
| }()); | |
| /** | |
| * Simple object to perform ambiguity check and to return name of time zone. | |
| */ | |
| jstz.TimeZone = function (tz_name) { | |
| 'use strict'; | |
| /** | |
| * The keys in this object are timezones that we know may be ambiguous after | |
| * a preliminary scan through the olson_tz object. | |
| * | |
| * The array of timezones to compare must be in the order that daylight savings | |
| * starts for the regions. | |
| */ | |
| var AMBIGUITIES = { | |
| 'America/Denver': ['America/Denver', 'America/Mazatlan'], | |
| 'America/Chicago': ['America/Chicago', 'America/Mexico_City'], | |
| 'America/Santiago': ['America/Santiago', 'America/Asuncion', 'America/Campo_Grande'], | |
| 'America/Montevideo': ['America/Montevideo', 'America/Sao_Paulo'], | |
| 'Asia/Beirut': ['Asia/Amman', 'Asia/Jerusalem', 'Asia/Beirut', 'Europe/Helsinki','Asia/Damascus'], | |
| 'Pacific/Auckland': ['Pacific/Auckland', 'Pacific/Fiji'], | |
| 'America/Los_Angeles': ['America/Los_Angeles', 'America/Santa_Isabel'], | |
| 'America/New_York': ['America/Havana', 'America/New_York'], | |
| 'America/Halifax': ['America/Goose_Bay', 'America/Halifax'], | |
| 'America/Godthab': ['America/Miquelon', 'America/Godthab'], | |
| 'Asia/Dubai': ['Europe/Moscow'], | |
| 'Asia/Dhaka': ['Asia/Yekaterinburg'], | |
| 'Asia/Jakarta': ['Asia/Omsk'], | |
| 'Asia/Shanghai': ['Asia/Krasnoyarsk', 'Australia/Perth'], | |
| 'Asia/Tokyo': ['Asia/Irkutsk'], | |
| 'Australia/Brisbane': ['Asia/Yakutsk'], | |
| 'Pacific/Noumea': ['Asia/Vladivostok'], | |
| 'Pacific/Tarawa': ['Asia/Kamchatka', 'Pacific/Fiji'], | |
| 'Pacific/Tongatapu': ['Pacific/Apia'], | |
| 'Asia/Baghdad': ['Europe/Minsk'], | |
| 'Asia/Baku': ['Asia/Yerevan','Asia/Baku'], | |
| 'Africa/Johannesburg': ['Asia/Gaza', 'Africa/Cairo'] | |
| }, | |
| timezone_name = tz_name, | |
| /** | |
| * Checks if a timezone has possible ambiguities. I.e timezones that are similar. | |
| * | |
| * For example, if the preliminary scan determines that we're in America/Denver. | |
| * We double check here that we're really there and not in America/Mazatlan. | |
| * | |
| * This is done by checking known dates for when daylight savings start for different | |
| * timezones during 2010 and 2011. | |
| */ | |
| ambiguity_check = function () { | |
| var ambiguity_list = AMBIGUITIES[timezone_name], | |
| length = ambiguity_list.length, | |
| i = 0, | |
| tz = ambiguity_list[0]; | |
| for (; i < length; i += 1) { | |
| tz = ambiguity_list[i]; | |
| if (jstz.date_is_dst(jstz.dst_start_for(tz))) { | |
| timezone_name = tz; | |
| return; | |
| } | |
| } | |
| }, | |
| /** | |
| * Checks if it is possible that the timezone is ambiguous. | |
| */ | |
| is_ambiguous = function () { | |
| return typeof (AMBIGUITIES[timezone_name]) !== 'undefined'; | |
| }; | |
| if (is_ambiguous()) { | |
| ambiguity_check(); | |
| } | |
| return { | |
| name: function () { | |
| return timezone_name; | |
| } | |
| }; | |
| }; | |
| jstz.olson = {}; | |
| /* | |
| * The keys in this dictionary are comma separated as such: | |
| * | |
| * First the offset compared to UTC time in minutes. | |
| * | |
| * Then a flag which is 0 if the timezone does not take daylight savings into account and 1 if it | |
| * does. | |
| * | |
| * Thirdly an optional 's' signifies that the timezone is in the southern hemisphere, | |
| * only interesting for timezones with DST. | |
| * | |
| * The mapped arrays is used for constructing the jstz.TimeZone object from within | |
| * jstz.determine_timezone(); | |
| */ | |
| jstz.olson.timezones = { | |
| '-720,0' : 'Pacific/Majuro', | |
| '-660,0' : 'Pacific/Pago_Pago', | |
| '-600,1' : 'America/Adak', | |
| '-600,0' : 'Pacific/Honolulu', | |
| '-570,0' : 'Pacific/Marquesas', | |
| '-540,0' : 'Pacific/Gambier', | |
| '-540,1' : 'America/Anchorage', | |
| '-480,1' : 'America/Los_Angeles', | |
| '-480,0' : 'Pacific/Pitcairn', | |
| '-420,0' : 'America/Phoenix', | |
| '-420,1' : 'America/Denver', | |
| '-360,0' : 'America/Guatemala', | |
| '-360,1' : 'America/Chicago', | |
| '-360,1,s' : 'Pacific/Easter', | |
| '-300,0' : 'America/Bogota', | |
| '-300,1' : 'America/New_York', | |
| '-270,0' : 'America/Caracas', | |
| '-240,1' : 'America/Halifax', | |
| '-240,0' : 'America/Santo_Domingo', | |
| '-240,1,s' : 'America/Santiago', | |
| '-210,1' : 'America/St_Johns', | |
| '-180,1' : 'America/Godthab', | |
| '-180,0' : 'America/Argentina/Buenos_Aires', | |
| '-180,1,s' : 'America/Montevideo', | |
| '-120,0' : 'America/Noronha', | |
| '-120,1' : 'America/Noronha', | |
| '-60,1' : 'Atlantic/Azores', | |
| '-60,0' : 'Atlantic/Cape_Verde', | |
| '0,0' : 'UTC', | |
| '0,1' : 'Europe/London', | |
| '60,1' : 'Europe/Berlin', | |
| '60,0' : 'Africa/Lagos', | |
| '60,1,s' : 'Africa/Windhoek', | |
| '120,1' : 'Asia/Beirut', | |
| '120,0' : 'Africa/Johannesburg', | |
| '180,0' : 'Asia/Baghdad', | |
| '180,1' : 'Europe/Moscow', | |
| '210,1' : 'Asia/Tehran', | |
| '240,0' : 'Asia/Dubai', | |
| '240,1' : 'Asia/Baku', | |
| '270,0' : 'Asia/Kabul', | |
| '300,1' : 'Asia/Yekaterinburg', | |
| '300,0' : 'Asia/Karachi', | |
| '330,0' : 'Asia/Kolkata', | |
| '345,0' : 'Asia/Kathmandu', | |
| '360,0' : 'Asia/Dhaka', | |
| '360,1' : 'Asia/Omsk', | |
| '390,0' : 'Asia/Rangoon', | |
| '420,1' : 'Asia/Krasnoyarsk', | |
| '420,0' : 'Asia/Jakarta', | |
| '480,0' : 'Asia/Shanghai', | |
| '480,1' : 'Asia/Irkutsk', | |
| '525,0' : 'Australia/Eucla', | |
| '525,1,s' : 'Australia/Eucla', | |
| '540,1' : 'Asia/Yakutsk', | |
| '540,0' : 'Asia/Tokyo', | |
| '570,0' : 'Australia/Darwin', | |
| '570,1,s' : 'Australia/Adelaide', | |
| '600,0' : 'Australia/Brisbane', | |
| '600,1' : 'Asia/Vladivostok', | |
| '600,1,s' : 'Australia/Sydney', | |
| '630,1,s' : 'Australia/Lord_Howe', | |
| '660,1' : 'Asia/Kamchatka', | |
| '660,0' : 'Pacific/Noumea', | |
| '690,0' : 'Pacific/Norfolk', | |
| '720,1,s' : 'Pacific/Auckland', | |
| '720,0' : 'Pacific/Tarawa', | |
| '765,1,s' : 'Pacific/Chatham', | |
| '780,0' : 'Pacific/Tongatapu', | |
| '780,1,s' : 'Pacific/Apia', | |
| '840,0' : 'Pacific/Kiritimati' | |
| }; | |
| if (typeof exports !== 'undefined') { | |
| exports.jstz = jstz; | |
| } else { | |
| root.jstz = jstz; | |
| } | |
| })(this); |
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