/*****
*
*   EventTarget.es
*
*   Authors: Kevin Lindsey, Antoine Quint
*
*****/


EventTarget.VERSION = 0.1;

function EventTarget() {
	if (arguments.length == 0) {
		this.Init();
	}
};

EventTarget.prototype.Init = function() {
	this._EventListeners = {};
};

EventTarget.prototype.handleEvent = function(e) {
	var handler = 'On' + e.type;
	if ( this[handler] == null ) {
		alert("Unsupported type: " + e.type);
	}
	this[handler](e);
};

EventTarget.prototype.AddEventListener = function(type, listener, useCapture) {
	var listeners = this._EventListeners[type];
    
	if ( listeners == null ) {
		listeners = [];
		this._EventListeners[type] = listeners;
	}

	listeners.push(listener);
};

EventTarget.prototype.RemoveEventListener = function(type, listener, useCapture) {
	var listeners = this._EventListeners[type];

	if ( listeners != null ) {
		for ( var i = 0; i < listeners.length; i++ ) {
			if ( listeners[i] === listener ) {
      	listeners.splice(i, 1);
        break;
      }
    }
  }
};

EventTarget.prototype.DispatchEvent = function(evt) {
	var listeners = this._EventListeners[evt.type];
	
	if ( listeners != null ) {
		for ( var i = listeners.length - 1; i >= 0; i-- ) {
			var listener = listeners[i];
			
			switch ( typeof(listener) ) {
				case "function": listener(evt);             break;
				case "object":   listener.handleEvent(evt); break;
				case "string":   eval(listener);            break;
				default:
					throw new Error(
							"Unrecognized event listener type: " + typeof(listener)
					);
			};
		}
	}
};

EventTarget.prototype.HasListener = function(type) {
	return this._EventListeners[type] != null;
};