Commits

Ilya Sedlovsky committed 9954bee

[*] Separate from other code using namespace
[*] Move demo code to index.html

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Files changed (2)

detect_timezone.js

  * This code is  maintained at bitbucket.org as jsTimezoneDetect.
  */
 
-var HEMISPHERE_SOUTH = 'SOUTH';
-var HEMISPHERE_NORTH = 'NORTH';
-var HEMISPHERE_UNKNOWN = 'N/A';
-var olson = {}
+/**
+ * Namespace to hold all the code for timezone detection.
+ */
+var jzTimezoneDetector = new Object();
 
-/**
- * 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 values of the dictionary are TimeZone objects.
- */
-olson.timezones = {
-	'-720,0'   : new TimeZone('-12:00','Etc/GMT+12', false),
-	'-660,0'   : new TimeZone('-11:00','Pacific/Pago_Pago', false),
-	'-600,1'   : new TimeZone('-11:00','America/Adak',true),
-	'-660,1,s' : new TimeZone('-11:00','Pacific/Apia', true),
-	'-600,0'   : new TimeZone('-10:00','Pacific/Honolulu', false),
-	'-570,0'   : new TimeZone('-10:30','Pacific/Marquesas',false),
-	'-540,0'   : new TimeZone('-09:00','Pacific/Gambier',false),
-	'-540,1'   : new TimeZone('-09:00','America/Anchorage', true),
-	'-480,1'   : new TimeZone('-08:00','America/Los_Angeles', true),
-	'-480,0'   : new TimeZone('-08:00','Pacific/Pitcairn',false),
-	'-420,0'   : new TimeZone('-07:00','America/Phoenix', false),
-	'-420,1'   : new TimeZone('-07:00','America/Denver', true),
-	'-360,0'   : new TimeZone('-06:00','America/Guatemala', false),
-	'-360,1'   : new TimeZone('-06:00','America/Chicago', true),
-	'-360,1,s' : new TimeZone('-06:00','Pacific/Easter',true),
-	'-300,0'   : new TimeZone('-05:00','America/Bogota', false),
-	'-300,1'   : new TimeZone('-05:00','America/New_York', true),
-	'-270,0'   : new TimeZone('-04:30','America/Caracas', false),
-	'-240,1'   : new TimeZone('-04:00','America/Halifax', true),
-	'-240,0'   : new TimeZone('-04:00','America/Santo_Domingo', false),
-	'-240,1,s' : new TimeZone('-04:00','America/Asuncion', true),
-	'-210,1'   : new TimeZone('-03:30','America/St_Johns', true),
-	'-180,1'   : new TimeZone('-03:00','America/Godthab', true),
-	'-180,0'   : new TimeZone('-03:00','America/Argentina/Buenos_Aires', false),
-	'-180,1,s' : new TimeZone('-03:00','America/Montevideo', true),
-	'-120,0'   : new TimeZone('-02:00','America/Noronha', false),
-	'-120,1'   : new TimeZone('-02:00','Etc/GMT+2', true),
-	'-60,1'    : new TimeZone('-01:00','Atlantic/Azores', true),
-	'-60,0'    : new TimeZone('-01:00','Atlantic/Cape_Verde', false),
-	'0,0'      : new TimeZone('00:00','Etc/UTC', false),
-	'0,1'      : new TimeZone('00:00','Europe/London', true),
-	'60,1'     : new TimeZone('+01:00','Europe/Berlin', true),
-	'60,0'     : new TimeZone('+01:00','Africa/Lagos', false),
-	'60,1,s'   : new TimeZone('+01:00','Africa/Windhoek',true),
-	'120,1'    : new TimeZone('+02:00','Asia/Beirut', true),
-	'120,0'    : new TimeZone('+02:00','Africa/Johannesburg', false),
-	'180,1'    : new TimeZone('+03:00','Europe/Moscow', true),
-	'180,0'    : new TimeZone('+03:00','Asia/Baghdad', false),
-	'210,1'    : new TimeZone('+03:30','Asia/Tehran', true),
-	'240,0'    : new TimeZone('+04:00','Asia/Dubai', false),
-	'240,1'    : new TimeZone('+04:00','Asia/Yerevan', true),
-	'270,0'    : new TimeZone('+04:30','Asia/Kabul', false),
-	'300,1'    : new TimeZone('+05:00','Asia/Yekaterinburg', true),
-	'300,0'    : new TimeZone('+05:00','Asia/Karachi', false),
-	'330,0'    : new TimeZone('+05:30','Asia/Kolkata', false),
-	'345,0'    : new TimeZone('+05:45','Asia/Kathmandu', false),
-	'360,0'    : new TimeZone('+06:00','Asia/Dhaka', false),
-	'360,1'    : new TimeZone('+06:00','Asia/Omsk', true),
-	'390,0'    : new TimeZone('+06:30','Asia/Rangoon', false),
-	'420,1'    : new TimeZone('+07:00','Asia/Krasnoyarsk', true),
-	'420,0'    : new TimeZone('+07:00','Asia/Jakarta', false),
-	'480,0'    : new TimeZone('+08:00','Asia/Shanghai', false),
-	'480,1'    : new TimeZone('+08:00','Asia/Irkutsk', true),
-	'525,0'    : new TimeZone('+08:45','Australia/Eucla', true),
-	'525,1,s'  : new TimeZone('+08:45','Australia/Eucla', true),
-	'540,1'    : new TimeZone('+09:00','Asia/Yakutsk', true),
-	'540,0'    : new TimeZone('+09:00','Asia/Tokyo', false),
-	'570,0'    : new TimeZone('+09:30','Australia/Darwin', false),
-	'570,1,s'  : new TimeZone('+09:30','Australia/Adelaide', true),
-	'600,0'    : new TimeZone('+10:00','Australia/Brisbane', false),
-	'600,1'	   : new TimeZone('+10:00','Asia/Vladivostok', true),
-	'600,1,s'  : new TimeZone('+10:00','Australia/Sydney', true),
-	'630,1,s'  : new TimeZone('+10:30','Australia/Lord_Howe', true),
-	'660,1'    : new TimeZone('+11:00','Asia/Kamchatka', true),
-	'660,0'    : new TimeZone('+11:00','Pacific/Noumea', false),
-	'690,0'    : new TimeZone('+11:30','Pacific/Norfolk', false),
-	'720,1,s'  : new TimeZone('+12:00','Pacific/Auckland', true),
-	'720,0'    : new TimeZone('+12:00','Pacific/Tarawa', false),
-	'765,1,s'  : new TimeZone('+12:45','Pacific/Chatham', true),
-	'780,0'    : new TimeZone('+13:00','Pacific/Tongatapu', false),
-	'840,0'    : new TimeZone('+14:00','Pacific/Kiritimati', false)
-}
-
-/**
- * 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.
- */
-olson.dst_start_dates = {
-	'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),
-	'Atlantic/Stanley' : new Date(2011, 8, 4, 7, 0, 0, 0),
-	'America/Asuncion' : new Date(2011, 9, 2, 3, 0, 0, 0),
-	'America/Santiago' : new Date(2011, 9, 9, 3, 0, 0, 0),
-	'America/Campo_Grande' : new Date(2011, 9, 16, 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(2011, 2, 13, 2, 0, 0, 0),
-	'America/New_York' : new Date(2011, 2, 13, 7, 0, 0, 0),
-	'Asia/Gaza' : new Date(2011, 2, 26, 23, 0, 0, 0),
-	'Asia/Beirut' : new Date(2011, 2, 27, 1, 0, 0, 0),
-	'Europe/Minsk' : new Date(2011, 2, 27, 3, 0, 0, 0),
-	'Europe/Istanbul' : new Date(2011, 2, 27, 7, 0, 0, 0),
-	'Asia/Damascus' : new Date(2011, 3, 1, 2, 0, 0, 0),
-	'Asia/Jerusalem' : new Date(2011, 3, 1, 6, 0, 0, 0),
-	'Africa/Cairo' : new Date(2011, 3, 29, 4, 0, 0, 0),
-	'Asia/Yerevan' : new Date(2011, 2, 27, 4, 0, 0, 0),
-	'Asia/Baku'    : new Date(2011, 2, 27, 8, 0, 0, 0),
-	'Pacific/Auckland' : new Date(2011, 8, 26, 7, 0, 0, 0),
-	'Pacific/Fiji' : new Date(2010, 11, 29, 23, 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)
-}
-
-/**
- * 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.
- */
-olson.ambiguity_list = {
-	'America/Denver' : ['America/Denver','America/Mazatlan'],
-	'America/Chicago' : ['America/Chicago','America/Mexico_City'],
-	'America/Asuncion' : ['Atlantic/Stanley', 'America/Asuncion', 'America/Santiago','America/Campo_Grande'],
-	'America/Montevideo' : ['America/Montevideo', 'America/Sao_Paulo'],
-	'Asia/Beirut' : ['Asia/Gaza','Asia/Beirut', 'Europe/Minsk', 'Europe/Istanbul', 'Asia/Damascus', 'Asia/Jerusalem','Africa/Cairo'],
-	'Asia/Yerevan' : ['Asia/Yerevan', 'Asia/Baku'],
-	'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']
-}
-
+jzTimezoneDetector.HEMISPHERE_SOUTH = 'SOUTH';
+jzTimezoneDetector.HEMISPHERE_NORTH = 'NORTH';
+jzTimezoneDetector.HEMISPHERE_UNKNOWN = 'N/A';
+jzTimezoneDetector.olson = {};
 
 /**
  * A simple object containing information of utc_offset, which olson timezone key to use, 
  * @param {string} olson_tz - the olson Identifier, such as "America/Denver"
  * @param {boolean} uses_dst - flag for whether the time zone somehow cares about daylight savings.
  */
-function TimeZone(offset, olson_tz, uses_dst) {
+jzTimezoneDetector.TimeZone = function (offset, olson_tz, uses_dst) {
 	this.utc_offset = offset;
 	this.olson_tz = olson_tz;
 	this.uses_dst = uses_dst;
  * Prints out the result.
  * But before it does that, it calls this.ambiguity_check.
  */
-TimeZone.prototype.display = function() {
+jzTimezoneDetector.TimeZone.prototype.display = function() {
 	this.ambiguity_check();
 	var response_text = '<b>UTC-offset</b>: ' + this.utc_offset + '<br/>';
 	response_text += '<b>Zoneinfo key</b>: ' + this.olson_tz + '<br/>';
  * This is done by checking known dates for when daylight savings start for different
  * timezones.
  */
-TimeZone.prototype.ambiguity_check = function() {
-	var local_ambiguity_list = olson.ambiguity_list[this.olson_tz];
+jzTimezoneDetector.TimeZone.prototype.ambiguity_check = function() {
+	var local_ambiguity_list = jzTimezoneDetector.olson.ambiguity_list[this.olson_tz];
 	
 	if (typeof(local_ambiguity_list) == 'undefined') {
 		return;
 	for (var i = 0; i < length; i++) {
 		var tz = local_ambiguity_list[i]
 
-		if (date_is_dst(olson.dst_start_dates[tz])) {
+		if (jzTimezoneDetector.date_is_dst(jzTimezoneDetector.olson.dst_start_dates[tz])) {
 			this.olson_tz = tz;
 			return;
 		}	
  * @param {Date} date
  * @returns {boolean}
  */
-function date_is_dst(date) {
-	var base_offset = ( (date.getMonth() > 5 ? get_june_offset() : get_january_offset()) )
+jzTimezoneDetector.date_is_dst = function (date) {
+	var base_offset = ( (date.getMonth() > 5 ? jzTimezoneDetector.get_june_offset() : jzTimezoneDetector.get_january_offset()) )
 	
-	var date_offset = get_date_offset(date);
+	var date_offset = jzTimezoneDetector.get_date_offset(date);
 	
 	return (base_offset - date_offset) != 0;
 }
  * @param date
  * @returns {number}
  */
-function get_date_offset(date) {
+jzTimezoneDetector.get_date_offset = function (date) {
 	return -date.getTimezoneOffset();
 }
 
  * 
  * @returns {Object}  
  */
-function get_timezone_info() {
-	var january_offset = get_january_offset();
+jzTimezoneDetector.get_timezone_info = function () {
+	var january_offset = jzTimezoneDetector.get_january_offset();
 	
-	var june_offset = get_june_offset();
+	var june_offset = jzTimezoneDetector.get_june_offset();
 	
 	var diff = january_offset - june_offset;
 
 	if (diff < 0) {
 	    return {'utc_offset' : january_offset,
 	    		'dst':	1,
-	    		'hemisphere' : HEMISPHERE_NORTH}
+	    		'hemisphere' : jzTimezoneDetector.HEMISPHERE_NORTH}
 	}
 	else if (diff > 0) {
         return {'utc_offset' : june_offset,
         		'dst' : 1,
-        		'hemisphere' : HEMISPHERE_SOUTH}
+        		'hemisphere' : jzTimezoneDetector.HEMISPHERE_SOUTH}
 	}
 
     return {'utc_offset' : january_offset, 
     		'dst': 0, 
-    		'hemisphere' : HEMISPHERE_UNKNOWN}
+    		'hemisphere' : jzTimezoneDetector.HEMISPHERE_UNKNOWN}
 }
 
-function get_january_offset() {
-	return get_date_offset(new Date(2011, 0, 1, 0, 0, 0, 0));
+jzTimezoneDetector.get_january_offset = function () {
+	return jzTimezoneDetector.get_date_offset(new Date(2011, 0, 1, 0, 0, 0, 0));
 }
 
-function get_june_offset() {
-	return get_date_offset(new Date(2011, 5, 1, 0, 0, 0, 0));
+jzTimezoneDetector.get_june_offset = function () {
+	return jzTimezoneDetector.get_date_offset(new Date(2011, 5, 1, 0, 0, 0, 0));
 }
 
 /**
  * 
  * @returns Object 
  */
-function determine_timezone() {
-	var timezone_key_info = get_timezone_info();
+jzTimezoneDetector.determine_timezone = function () {
+	var timezone_key_info = jzTimezoneDetector.get_timezone_info();
 	
 	var hemisphere_suffix = ''
 		
-	if (timezone_key_info.hemisphere == HEMISPHERE_SOUTH) {
+	if (timezone_key_info.hemisphere == jzTimezoneDetector.HEMISPHERE_SOUTH) {
 		hemisphere_suffix = ',s';
 	}
 	
 	var tz_key = timezone_key_info.utc_offset + ',' + timezone_key_info.dst + hemisphere_suffix
 	
-	return {'timezone' : olson.timezones[tz_key], 'key' : tz_key}
+	return {'timezone' : jzTimezoneDetector.olson.timezones[tz_key], 'key' : tz_key}
 }
 
 /**
- * This is the entry point of the application.
+ * 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 values of the dictionary are TimeZone objects.
  */
-function show_timezone_info() {
-	var tz_info = determine_timezone();
-	
-	response_text = 'No timezone found for ' + tz_info.key;
-	
-	if (typeof(tz_info.timezone) == 'undefined') {
-		response_text = 'No timezone found for ' + tz_info.key;
-	}
-	else {
-		response_text = tz_info.timezone.display(); 
-	}
-	
-	document.getElementById('tz_info').innerHTML = response_text
-	
-	$('#tz_info').fadeIn(3000);
+jzTimezoneDetector.olson.timezones = {
+    '-720,0'   : new jzTimezoneDetector.TimeZone('-12:00','Etc/GMT+12', false),
+    '-660,0'   : new jzTimezoneDetector.TimeZone('-11:00','Pacific/Pago_Pago', false),
+    '-600,1'   : new jzTimezoneDetector.TimeZone('-11:00','America/Adak',true),
+    '-660,1,s' : new jzTimezoneDetector.TimeZone('-11:00','Pacific/Apia', true),
+    '-600,0'   : new jzTimezoneDetector.TimeZone('-10:00','Pacific/Honolulu', false),
+    '-570,0'   : new jzTimezoneDetector.TimeZone('-10:30','Pacific/Marquesas',false),
+    '-540,0'   : new jzTimezoneDetector.TimeZone('-09:00','Pacific/Gambier',false),
+    '-540,1'   : new jzTimezoneDetector.TimeZone('-09:00','America/Anchorage', true),
+    '-480,1'   : new jzTimezoneDetector.TimeZone('-08:00','America/Los_Angeles', true),
+    '-480,0'   : new jzTimezoneDetector.TimeZone('-08:00','Pacific/Pitcairn',false),
+    '-420,0'   : new jzTimezoneDetector.TimeZone('-07:00','America/Phoenix', false),
+    '-420,1'   : new jzTimezoneDetector.TimeZone('-07:00','America/Denver', true),
+    '-360,0'   : new jzTimezoneDetector.TimeZone('-06:00','America/Guatemala', false),
+    '-360,1'   : new jzTimezoneDetector.TimeZone('-06:00','America/Chicago', true),
+    '-360,1,s' : new jzTimezoneDetector.TimeZone('-06:00','Pacific/Easter',true),
+    '-300,0'   : new jzTimezoneDetector.TimeZone('-05:00','America/Bogota', false),
+    '-300,1'   : new jzTimezoneDetector.TimeZone('-05:00','America/New_York', true),
+    '-270,0'   : new jzTimezoneDetector.TimeZone('-04:30','America/Caracas', false),
+    '-240,1'   : new jzTimezoneDetector.TimeZone('-04:00','America/Halifax', true),
+    '-240,0'   : new jzTimezoneDetector.TimeZone('-04:00','America/Santo_Domingo', false),
+    '-240,1,s' : new jzTimezoneDetector.TimeZone('-04:00','America/Asuncion', true),
+    '-210,1'   : new jzTimezoneDetector.TimeZone('-03:30','America/St_Johns', true),
+    '-180,1'   : new jzTimezoneDetector.TimeZone('-03:00','America/Godthab', true),
+    '-180,0'   : new jzTimezoneDetector.TimeZone('-03:00','America/Argentina/Buenos_Aires', false),
+    '-180,1,s' : new jzTimezoneDetector.TimeZone('-03:00','America/Montevideo', true),
+    '-120,0'   : new jzTimezoneDetector.TimeZone('-02:00','America/Noronha', false),
+    '-120,1'   : new jzTimezoneDetector.TimeZone('-02:00','Etc/GMT+2', true),
+    '-60,1'    : new jzTimezoneDetector.TimeZone('-01:00','Atlantic/Azores', true),
+    '-60,0'    : new jzTimezoneDetector.TimeZone('-01:00','Atlantic/Cape_Verde', false),
+    '0,0'      : new jzTimezoneDetector.TimeZone('00:00','Etc/UTC', false),
+    '0,1'      : new jzTimezoneDetector.TimeZone('00:00','Europe/London', true),
+    '60,1'     : new jzTimezoneDetector.TimeZone('+01:00','Europe/Berlin', true),
+    '60,0'     : new jzTimezoneDetector.TimeZone('+01:00','Africa/Lagos', false),
+    '60,1,s'   : new jzTimezoneDetector.TimeZone('+01:00','Africa/Windhoek',true),
+    '120,1'    : new jzTimezoneDetector.TimeZone('+02:00','Asia/Beirut', true),
+    '120,0'    : new jzTimezoneDetector.TimeZone('+02:00','Africa/Johannesburg', false),
+    '180,1'    : new jzTimezoneDetector.TimeZone('+03:00','Europe/Moscow', true),
+    '180,0'    : new jzTimezoneDetector.TimeZone('+03:00','Asia/Baghdad', false),
+    '210,1'    : new jzTimezoneDetector.TimeZone('+03:30','Asia/Tehran', true),
+    '240,0'    : new jzTimezoneDetector.TimeZone('+04:00','Asia/Dubai', false),
+    '240,1'    : new jzTimezoneDetector.TimeZone('+04:00','Asia/Yerevan', true),
+    '270,0'    : new jzTimezoneDetector.TimeZone('+04:30','Asia/Kabul', false),
+    '300,1'    : new jzTimezoneDetector.TimeZone('+05:00','Asia/Yekaterinburg', true),
+    '300,0'    : new jzTimezoneDetector.TimeZone('+05:00','Asia/Karachi', false),
+    '330,0'    : new jzTimezoneDetector.TimeZone('+05:30','Asia/Kolkata', false),
+    '345,0'    : new jzTimezoneDetector.TimeZone('+05:45','Asia/Kathmandu', false),
+    '360,0'    : new jzTimezoneDetector.TimeZone('+06:00','Asia/Dhaka', false),
+    '360,1'    : new jzTimezoneDetector.TimeZone('+06:00','Asia/Omsk', true),
+    '390,0'    : new jzTimezoneDetector.TimeZone('+06:30','Asia/Rangoon', false),
+    '420,1'    : new jzTimezoneDetector.TimeZone('+07:00','Asia/Krasnoyarsk', true),
+    '420,0'    : new jzTimezoneDetector.TimeZone('+07:00','Asia/Jakarta', false),
+    '480,0'    : new jzTimezoneDetector.TimeZone('+08:00','Asia/Shanghai', false),
+    '480,1'    : new jzTimezoneDetector.TimeZone('+08:00','Asia/Irkutsk', true),
+    '525,0'    : new jzTimezoneDetector.TimeZone('+08:45','Australia/Eucla', true),
+    '525,1,s'  : new jzTimezoneDetector.TimeZone('+08:45','Australia/Eucla', true),
+    '540,1'    : new jzTimezoneDetector.TimeZone('+09:00','Asia/Yakutsk', true),
+    '540,0'    : new jzTimezoneDetector.TimeZone('+09:00','Asia/Tokyo', false),
+    '570,0'    : new jzTimezoneDetector.TimeZone('+09:30','Australia/Darwin', false),
+    '570,1,s'  : new jzTimezoneDetector.TimeZone('+09:30','Australia/Adelaide', true),
+    '600,0'    : new jzTimezoneDetector.TimeZone('+10:00','Australia/Brisbane', false),
+    '600,1'    : new jzTimezoneDetector.TimeZone('+10:00','Asia/Vladivostok', true),
+    '600,1,s'  : new jzTimezoneDetector.TimeZone('+10:00','Australia/Sydney', true),
+    '630,1,s'  : new jzTimezoneDetector.TimeZone('+10:30','Australia/Lord_Howe', true),
+    '660,1'    : new jzTimezoneDetector.TimeZone('+11:00','Asia/Kamchatka', true),
+    '660,0'    : new jzTimezoneDetector.TimeZone('+11:00','Pacific/Noumea', false),
+    '690,0'    : new jzTimezoneDetector.TimeZone('+11:30','Pacific/Norfolk', false),
+    '720,1,s'  : new jzTimezoneDetector.TimeZone('+12:00','Pacific/Auckland', true),
+    '720,0'    : new jzTimezoneDetector.TimeZone('+12:00','Pacific/Tarawa', false),
+    '765,1,s'  : new jzTimezoneDetector.TimeZone('+12:45','Pacific/Chatham', true),
+    '780,0'    : new jzTimezoneDetector.TimeZone('+13:00','Pacific/Tongatapu', false),
+    '840,0'    : new jzTimezoneDetector.TimeZone('+14:00','Pacific/Kiritimati', false)
 }
-onload = show_timezone_info;
+
+/**
+ * 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.
+ */
+jzTimezoneDetector.olson.dst_start_dates = {
+    '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),
+    'Atlantic/Stanley' : new Date(2011, 8, 4, 7, 0, 0, 0),
+    'America/Asuncion' : new Date(2011, 9, 2, 3, 0, 0, 0),
+    'America/Santiago' : new Date(2011, 9, 9, 3, 0, 0, 0),
+    'America/Campo_Grande' : new Date(2011, 9, 16, 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(2011, 2, 13, 2, 0, 0, 0),
+    'America/New_York' : new Date(2011, 2, 13, 7, 0, 0, 0),
+    'Asia/Gaza' : new Date(2011, 2, 26, 23, 0, 0, 0),
+    'Asia/Beirut' : new Date(2011, 2, 27, 1, 0, 0, 0),
+    'Europe/Minsk' : new Date(2011, 2, 27, 3, 0, 0, 0),
+    'Europe/Istanbul' : new Date(2011, 2, 27, 7, 0, 0, 0),
+    'Asia/Damascus' : new Date(2011, 3, 1, 2, 0, 0, 0),
+    'Asia/Jerusalem' : new Date(2011, 3, 1, 6, 0, 0, 0),
+    'Africa/Cairo' : new Date(2011, 3, 29, 4, 0, 0, 0),
+    'Asia/Yerevan' : new Date(2011, 2, 27, 4, 0, 0, 0),
+    'Asia/Baku'    : new Date(2011, 2, 27, 8, 0, 0, 0),
+    'Pacific/Auckland' : new Date(2011, 8, 26, 7, 0, 0, 0),
+    'Pacific/Fiji' : new Date(2010, 11, 29, 23, 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)
+}
+
+/**
+ * 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.
+ */
+jzTimezoneDetector.olson.ambiguity_list = {
+    'America/Denver' : ['America/Denver','America/Mazatlan'],
+    'America/Chicago' : ['America/Chicago','America/Mexico_City'],
+    'America/Asuncion' : ['Atlantic/Stanley', 'America/Asuncion', 'America/Santiago','America/Campo_Grande'],
+    'America/Montevideo' : ['America/Montevideo', 'America/Sao_Paulo'],
+    'Asia/Beirut' : ['Asia/Gaza','Asia/Beirut', 'Europe/Minsk', 'Europe/Istanbul', 'Asia/Damascus', 'Asia/Jerusalem','Africa/Cairo'],
+    'Asia/Yerevan' : ['Asia/Yerevan', 'Asia/Baku'],
+    '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']
+}
   </style>
   <script type="text/javascript" src='detect_timezone.js'></script>
   <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
+  <script type="text/javascript">
+  $("body").ready(function () {
+        var tz_info = jzTimezoneDetector.determine_timezone();
+        
+        response_text = 'No timezone found for ' + tz_info.key;
+        
+        if (typeof(tz_info.timezone) == 'undefined') {
+            response_text = 'No timezone found for ' + tz_info.key;
+        }
+        else {
+            response_text = tz_info.timezone.display(); 
+        }
+        
+        document.getElementById('tz_info').innerHTML = response_text
+        
+        $('#tz_info').fadeIn(3000);
+    });
+  </script>
 </head>
 
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