/**
* 
* @module Kiwi
* @submodule Time
*
*/

module Kiwi.Time {

	/**
	* The MasterClock tracks time elapsed since the application started.
	* Each ClockManager has only one MasterClock which is automatically generated when the game initially booted.
	* You should not access it directly, use the Clock and Timer classes instead.
	*
	* @class MasterClock
	* @namespace Kiwi.Time
	* @constructor
	* @return {Kiwi.Time.MasterClock} This Object.
	*
	*/
	export class MasterClock {

		constructor () {

			this._started = Date.now();
			this.now = Date.now();
			this.time = this._started;

		}

		/**
		* The type of object that this is.
		* @method objType
		* @return {String} "MasterClock"
		* @public
		*/
		public objType() {
			return "MasterClock";
		}

		/**
		* The time when the MasterClock was started.
		* @property _started
		* @type Number
		* @private
		*/
		private _started: number;

		/**
		* The current time. This is updated every frame but AFTER the delta is calculated.
		* @property time
		* @type Number
		* @public
		*/
		public time: number = 0;

		/**
		* The current time, this is straight from the Date.now() method and is updated every frame BEFORE the delta.
		* @property now
		* @type Number
		* @public
		*/
		public now: number = 0;

		/**
		* The time it takes for the time to update. Using this you can calculate the fps.
		* @property delta
		* @type Number
		* @public
		*/
		public delta: number = 0;

		/**
		* The rate at which ideal frames are passing. Multiply per-frame iterations by this factor to create smooth movement. For example, if the ideal fps is 60, but you're only getting 45, rate will equal 1.333.
		* @property rate
		* @type Number
		* @public
		* @since 1.1.0
		*/
		public rate = 1;

		/**
		* The ideal frame delta in milliseconds. This is automatically adjusted when the game sets a new frameRate.
		* @property idealDelta
		* @type Number
		* @public
		* @since 1.1.0
		*/
		public idealDelta = 1000/60.0;

		/**
		* The time that has elapsed since the game started. In milliseconds.
		* @method elapsed
		* @return {Number}
		* @public
		*/
		public elapsed():number {

			return this.now - this._started;

		}

		/**
		* The time that has elapsed since the game started but in seconds.
		* @method totalElapsedSeconds
		* @return {Number}
		* @public
		*/
		public totalElapsedSeconds(): number {

			return (this.now - this._started) * 0.001;

		}

		/**
		* The update loop that should be executed every frame. Used to update the time.
		* @method update
		* @public
		*/
		public update() {

			//  Not in < IE8 (fixed via polyfill)
			this.now = Date.now();

			this.delta = this.now - this.time;

			this.time = this.now;

			this.rate = this.delta / this.idealDelta;

			//  Apply time scaling

		}

		/**
		* Used to calculate the elapsed time from a point that is specified. This is returned in Milliseconds.
		* @method elapsedSince
		* @param since {Number} The point in time in which you would like to see how many milliseconds have passed. In milliseconds.
		* @return {Number}
		* @public
		*/
		public elapsedSince(since: number): number {

			return this.now - since;

		}

		/**
		* Used to calculate the elapsed time from a point that is specified BUT this is in seconds.
		* @method elapsedSecondsSince
		* @param since {Number} The point in time in which you would like to see how many seconds have passed. In milliseconds.
		* @return {Number }
		* @public
		*/
		public elapsedSecondsSince(since: number): number {

			return (this.now - since) * 0.001;

		}

		/**
		* Resets the MasterClocks time.
		* @method reset
		* @public
		*/
		public reset() {

			this._started = this.now;

		}

	}

}