Merge pull request trentrichardson#424 from Zauberfisch/dev

BUGFIX timeZoneString UTC & UTC+5.5

Author: trentrichardson

jquery-ui-timepicker-addon.js

@@ -471,7 +471,7 @@ $.extend(Timepicker.prototype, {
 			);
 			if (typeof(this.timezone) != "undefined" && this.timezone !== null && this.timezone !== "") {
 				var local_date = new Date(this.inst.selectedYear, this.inst.selectedMonth, this.inst.selectedDay, 12);
-				var local_timezone = timeZoneString(local_date);
+				var local_timezone = $.timepicker.timeZoneOffsetString(local_date);
 				if (local_timezone == this.timezone) {
 					selectLocalTimeZone(tp_inst);
 				} else {
@@ -1553,26 +1553,29 @@ var selectLocalTimeZone = function(tp_inst, date)
 	if (tp_inst && tp_inst.timezone_select) {
 		tp_inst._defaults.useLocalTimezone = true;
 		var now = typeof date !== 'undefined' ? date : new Date();
-		var tzoffset = timeZoneString(now);
+		var tzoffset = $.timepicker.timeZoneOffsetString(now);
 		if (tp_inst._defaults.timezoneIso8601) {
 			tzoffset = tzoffset.substring(0, 3) + ':' + tzoffset.substring(3);
         }
 		tp_inst.timezone_select.val(tzoffset);
 	}
 };
 
-// Input: Date Object
-// Output: String with timezone offset, e.g. '+0100'
-var timeZoneString = function(date)
-{
-	var off = date.getTimezoneOffset() * -10100 / 60;
-	var timezone = (off >= 0 ? '+' : '-') + Math.abs(off).toString().substr(1);
-	return timezone;
-};
-
 $.timepicker = new Timepicker(); // singleton instance
 $.timepicker.version = "1.0.2";
 
+/**
+ * Get the timezone offset as string from a date object (eg '+0530' for UTC+5.5)
+ * @param  date
+ * @return string
+ */
+$.timepicker.timeZoneOffsetString = function(date) {
+	var off = date.getTimezoneOffset() * -1,
+		minutes = off % 60,
+		hours = (off-minutes) / 60;
+	return (off >= 0 ? '+' : '-') + ('0'+(hours*101).toString()).substr(-2) + ('0'+(minutes*101).toString()).substr(-2);
+};
+
 //#######################################################################################
 // Changes by simonvwade to better handle time range limits
 //#######################################################################################