/**
 * https://github.com/mrdoob/eventtarget.js/
 * THankS mr DOob!
 */

/**
 * Adds event emitter functionality to a class
 *
 * @class EventTarget
 * @example
 *		function MyEmitter() {
 *			PIXI.EventTarget.call(this); //mixes in event target stuff
 *		}
 *
 *		var em = new MyEmitter();
 *		em.emit({ type: 'eventName', data: 'some data' });
 */
PIXI.EventTarget = function () {

	var listeners = {};

	this.addEventListener = this.on = function ( type, listener ) {


		if ( listeners[ type ] === undefined ) {

			listeners[ type ] = [];

		}

		if ( listeners[ type ].indexOf( listener ) === - 1 ) {

			listeners[ type ].push( listener );
		}

	};

	this.dispatchEvent = this.emit = function ( event ) {

		if ( !listeners[ event.type ] || !listeners[ event.type ].length ) {

			return;

		}

		for(var i = 0, l = listeners[ event.type ].length; i < l; i++) {

			listeners[ event.type ][ i ]( event );

		}

	};

	this.removeEventListener = this.off = function ( type, listener ) {

		var index = listeners[ type ].indexOf( listener );

		if ( index !== - 1 ) {

			listeners[ type ].splice( index, 1 );

		}

	};

};