/**
* 
* @module Kiwi
* 
*/

module Kiwi {

	/**
	* Used to handle the creation and management of Cameras on a Game. Each Game will always have created for it a CameraManager and a default Camera on the manager. 
	* Games currently only usupport the use of a single camera, the default camera. Much of this class has been written with future multiple camera support in mind. 
	* 
	* @class CameraManager
	* @namespace Kiwi
	* @constructor
	* @param {Kiwi.Game} game
	* @return {Kiwi.CameraManager} 
	*/
	export class CameraManager {

		constructor(game: Kiwi.Game) {

			this._game = game;
			this._cameras = [];
			this._nextCameraID = 0;

		}

		/**
		* Returns the type of this object
		* @method objType
		* @return {String} "CameraManager"
		* @public
		*/
		public objType():string {
			return "CameraManager";
		}

		/**
		* The game this object belongs to
		* @property _game
		* @type Kiwi.Game
		* @private
		*/
		private _game: Kiwi.Game;

		/**
		* A collection of cameras
		* @property _cameras
		* @type Array
		* @private
		*/
		private _cameras: Kiwi.Camera[];

		/**
		* The id which will be used when next creating a camera
		* @property _nextCameraID
		* @type Number
		* @private
		*/
		private _nextCameraID: number;

		/**
		* The default camera that is on this manager.
		* @property defaultCamera
		* @type Kiwi.Camara
		* @public
		*/
		public defaultCamera: Kiwi.Camera;

		/**
		* Initializes the CameraManager, creates a new camera and assigns it to the defaultCamera
		* @method boot
		* @public
		*/
		public boot() {

			this.create("defaultCamera", 0, 0, this._game.stage.width, this._game.stage.height);
			this.defaultCamera = this._cameras[0];
		}

		/**
		* Creates a new Camera and adds it to the collection of cameras.
		* @param {String} name. The name of the new camera.
		* @param {Number} x. The x position of the new camera.
		* @param {Number} y. The y position of the new camera.
		* @param {Number} width. The width of the new camera.
		* @param {Number} height. The height of the new camera.
		* @return {Kiwi.Camera} The new camera object.
		* @public
		*/
		public create(name: string, x: number, y: number, width: number, height: number): Kiwi.Camera {
			var newCamera: Kiwi.Camera = new Kiwi.Camera(this._game, this._nextCameraID++,name,x,y,width,height);

			//newCamera.parent = state;

			this._cameras.push(newCamera);

			return newCamera;

		}

		/**
		* Removes the given camera, if it is present in the camera managers camera collection.
		* @method remove
		* @param camera {Kiwi.Camera}
		* @return {boolean} True if the camera was removed, false otherwise.
		* @public
		*/
		public remove(camera: Kiwi.Camera):boolean {
			var i = this._cameras.indexOf(camera); //what if it was the default one! :(

			if (i !== -1) {
				//  Send Layer a killed call
				this._cameras.splice(i, 1);
				return true;
			}

			return false;
		}

		/**
		* Calls update on all the cameras.
		* @method update
		* @public
		*/
		public update() {

			if (this._cameras.length === 0) {
				return false;
			}

			for (var i = 0; i < this._cameras.length; i++) {
				this._cameras[i].update();
			}

		}

		/**
		* Calls the render method on all the cameras
		* @method render
		* @public
		*/
		public render() {

			if (this._cameras.length === 0) {
				return false;
			}

			//render each camera
			for (var i = 0; i < this._cameras.length; i++) {
				this._cameras[i].render();
			}

		}

		/**
		* Removes all cameras in the camera Manager except the default camera. Does nothing if in multi camera mode.
		* @method removeAll
		* @public
		*/
		public removeAll() {
			this._cameras = []; 
		}

		/**
		* Returns all cameras to origin. Called when starting a new state.
		* @method zeroAllCameras
		* @public
		* @since 1.1.0
		*/
		public zeroAllCameras() {
			for( var i = 0;  i < this._cameras.length;  i++ )
			{
				this.zeroCamera( this._cameras[i] );
			}
			this.zeroCamera( this.defaultCamera );
		}

		/**
		* Returns camera to origin.
		* @method zeroCamera
		* @param camera {Kiwi.Camera}
		* @public
		* @since 1.1.0
		*/
		public zeroCamera(camera:Kiwi.Camera)
		{
			camera.transform.x = 0;
			camera.transform.y = 0;
			camera.transform.rotation = 0;
			camera.transform.scaleX = 1;
			camera.transform.scaleY = 1;
			camera.transform.rotPointX = camera.width / 2;
			camera.transform.rotPointY = camera.height / 2;
		}

	}
}