AlarmManager.js

var Time = function(hour, minute, second){

  var getNextOccurrence = function(){
    var date = new Date();
    date.setHours(hour, minute, second);

    var currentTime = new Date();

    // If the alarm time is in the past, move it to the next day
    if(date.getTime() < currentTime.getTime()){
      date.setTime(date.getTime() + 86400000); // Increment by 1 day in millis
    }

    return date;
  };

  return {
    hour: hour,
    minute: minute,
    second: second,
    getNextOccurrence: getNextOccurrence
  };
};

var AlarmManager = (function(){

  var AlarmClockInfo = function(tag, triggerTime, intervalTime, operation){
    return {
      tag: tag,
      triggerTime: triggerTime,
      intervalTime: intervalTime,
      operation: operation
    };
  };

  var alarms = [];
  var alarmIds = [];

  var cancelAlarm = function(alarmIndex){
    clearTimeout(alarmIds[alarmIndex]);
    alarms.splice(alarmIndex, 1);
    alarmIds.splice(alarmIndex, 1);
  };

  var cancel = function(operation){
    if (typeof(operation) === "string") {
      var tag = operation;
      for (var i = alarms.length - 1; i >= 0; i--){
        if (alarms[i].tag === tag) {
          cancelAlarm(i);
        }
      }
    } else {
      for (var i = alarms.length - 1; i >= 0; i--){
        if (alarms[i].operation === operation) {
          cancelAlarm(i);
        }
      }
    }
  };

  var getNextAlarm = function(){
    if (alarms.length > 0) {
      var min = alarms[0];
      for (var i = 0; i < alarms.length; i++) {
        var alarm = alarms[i];
        if (alarm.triggerTime < min.triggerTime) {
          min = alarm;
        }
      }
      return min;
    }
    return null;
  };

  var getAllAlarms = function(){
    return alarms;
  };

  var addAlarm = function(alarm){
    var id = setTimeout(function(){
      alarm.operation();
      cancel(alarm.operation);
      if (alarm.intervalTime > 0) {
        setRepeating(alarm.tag, parseInt(new Date().getTime() + alarm.intervalTime), alarm.intervalTime, alarm.operation);
      }
    }, parseInt(alarm.triggerTime - new Date()));

    alarms.push(alarm);
    alarmIds.push(id);
  };

  var set = function(tag, triggerAtMillis, operation){
    var alarm = new AlarmClockInfo(tag, triggerAtMillis, -1, operation);
    addAlarm(alarm);
  };

  var setRepeating = function(tag, triggerAtMillis, intervalMillis, operation){
    var alarm = new AlarmClockInfo(tag, triggerAtMillis, intervalMillis, operation);
    addAlarm(alarm);
  };

  return {
    cancel: cancel,
    getNextAlarm: getNextAlarm,
    getAllAlarms: getAllAlarms,
    set: set,
    setRepeating: setRepeating
  };

})();