Javascript - Alarm Manager like https://developer.chrome.com/apps/alarms

Javascript - Alarm Manager

var Alarm = function () {
	this.name;
	this.scheduledTime;
	this.periodInMinutes;
};

var AlarmManager = function () {
	var alarms = {},
		timerOuts = {},
		timerIntervels = {},
		self = this,
		onAlarmListener = null;

	var setOneTimeTimer = function (alarmName) {
		var alarm = alarms[alarmName];
		var delayInMilliSeconds = alarm.scheduledTime - Date.now();
		var timeout = setTimeout(function (alarmName) {
			return function () { // SetTimeout Callback function
				var l_alarm = alarms[alarmName];
				setRepeatedTimer(alarmName);
				
				// OnAlarm callback function
				if(onAlarmListener)
					onAlarmListener(l_alarm);
			};
		}(alarmName), delayInMilliSeconds);

		timerOuts[alarmName] = timeout;
	};

	var setRepeatedTimer = function (alarmName) {
		var alarm = alarms[alarmName];
		// Set Interval if the alarm has periodInMinutes
		if(alarm.periodInMinutes) {
			var intervalInMilliSeconds = alarm.periodInMinutes * 60 * 1000;
			var timeInterval = setInterval(function (alarmName) {
				return function () {
					// OnAlarm callback function
					if(onAlarmListener)
						onAlarmListener(alarms[alarmName]);
				};
			}(alarmName), intervalInMilliSeconds);
			timerIntervels[alarmName] = timeInterval;
		}
	};

	this.create = function (alarmName, alarmInfo) {
		var alarm = new Alarm();
		alarm.name = alarmName;
		if(!alarmInfo['delayInMinutes'])
			alarm.scheduledTime = alarmInfo['when'];
		else 
			alarm.scheduledTime = Date.now() + (alarmInfo['delayInMinutes'] * 60 * 1000);
		alarm.periodInMinutes = alarmInfo['periodInMinutes'];

		alarms[alarmName] = alarm;

		setOneTimeTimer(alarmName);
	};

	this.get = function (alarmName, callback){
		callback(alarms[alarmName]);
	};

	this.getAll = function (callback){
		for(var alarmName in alarms)
			alarmList.push(alarms[alarmName]);
		callback(alarmList);
	};

	this.clear = function (alarmName, callback){
		clearTimeout(timerOuts[alarmName]); // Clear Timeout
		delete timerOuts[alarmName];
		clearInterval(timerIntervels[alarmName]);// Clear Interval
		delete timerIntervels[alarmName];
		delete alarms[alarmName];
		callback(true);
	};

	this.clearAll = function (callback) {
		for (var alarmName in alarms) {
			clearTimeout(timerOuts[alarmName]);
			delete timerOuts[alarmName];
			clearInterval(timerIntervels[alarmName]);
			delete timerIntervels[alarmName];
			delete alarms[alarmName];
		}
		callback(true);	
	};

	this.addListener = function (callback){
		if(callback)
			onAlarmListener = callback;
	};
};

var alarmManager = new AlarmManager();