/*--------------------------------------------------------
 * Copyright © 2009 – 2010* France Telecom
 * This software is distributed under the "Simplified BSD license",
 * the text of which is available at http://www.winktoolkit.org/licence.txt
 * or see the "license.txt" file for more details.
 *--------------------------------------------------------*/

/**
 * Implements an encapsulation of an event
 * 
 * @properties:
 * 	data =
 * 	{
 * 		type 			= type of event (start, move, end, gesturestart, gesturemove, gestureend)
 * 		x				= x coordinate of the event
 * 		y				= y coordinate of the event
 * 		timestamp		= the event timestamp
 * 		target			= the target element
 * 		srcEvent		= the original source event
 * 		multitouch		= boolean that indicates whether the current event occurs in a multi-touch context
 * 	}
 * 
 * @methods:
 * 	--> preventDefault: allows to prevent default behavior
 *  --> stopPropagation: allows to stop event propagation
 * 	--> dispatch: assigns the event to another target
 * 
 * @attributes:
 *  --> uId: unique identifier of the component
 *  --> type: the type of event (start, move, end, gesturestart, gesturemove, gestureend)
 *  --> x: the x coordinate of the event
 *  --> y: the y coordinate of the event
 *  --> timestamp: the timestamp of the event
 *  --> target: the event target
 *  --> srcEvent: the original source event
 *  --> multitouch: a boolean that indicates whether there was more than one touch when the event was raised
 * 
 * @compatibility
 *  --> Iphone OS2, Iphone OS3, Iphone OS4, Android 1.5, Android 2.1, Android 2.2, Android 2.3, BlackBerry 6, Bada 1.0
 * 
 * @author:
 * 	--> Sylvain LALANDE
 */

(function(wink) {
	
var undef = wink.isUndefined;
var isSet = wink.isSet;

wink.ux.Event = function(properties)
{
	this.uId		= wink.getUId();
	wink.mixin(this, properties);
	
	if (this._validateProperties() === false) return;
};

wink.ux.Event.prototype = 
{
	/**
	 * allows to prevent default behavior
	 */
	preventDefault: function()
	{
		this.srcEvent.preventDefault();
	},

	/**
	 * allows to stop event propagation
	 */
	stopPropagation: function()
	{
		this.srcEvent.stopPropagation();
	},

	/**
	 * assigns the event to another target
	 * 
	 * @parameters:
	 * 	--> target: the dom node that will receive the event
	 * 	--> type: [optional] dispatch as this type
	 */
	dispatch: function(target, type)
	{
		var srcEvent = this.srcEvent;
		var targetedType = srcEvent.type;
		if (isSet(type))
		{
			targetedType = type;
		}
		var cloneEvent = _createEvent(srcEvent, targetedType);
		target.dispatchEvent(cloneEvent);
	},
	
	/**
	 * Check if the properties are correct
	 */
	_validateProperties: function()
	{
		var l = function(p) {
			wink.log('[Event] ' + p + ' must be specified');
		};
		if ( !isSet(this.type) || this.type == '' )
		{
			l('type');
			return false;
		}
		if ( undef(this.x) )
		{
			l('x');
			return false;
		}
		if ( undef(this.y) )
		{
			l('y');
			return false;
		}
		if ( !isSet(this.timestamp) )
		{
			l('timestamp');
			return false;
		}
		if ( undef(this.target) )
		{
			l('target');
			return false;
		}
		if ( !isSet(this.srcEvent) )
		{
			l('srcEvent');
			return false;
		}
	}
};

/**
 * 
 * @parameters:
 * 	--> sourceEvent: the source event
 *  --> type: the event type
 * 
 * @return a new event
 */
var _createEvent = function(sourceEvent, type)
{
	var s = sourceEvent;
	var eventInterface = "HTMLEvents";
	
	if (/blur|focus|resize|scroll/i.test(type)) {
		eventInterface = "UIEvent";
	} else if (/click|mouse(down|move|up)/i.test(type)) {
		eventInterface = "MouseEvent";
	} else if (/touch(start|move|end|cancel)/i.test(type)) {
		eventInterface = "TouchEvent";
	}
	
	var event = document.createEvent(eventInterface);
	var ct = s.changedTouches;
	if (eventInterface == "HTMLEvents") {
		event.initEvent(type, s.bubbles, s.cancelable);
	} else if (eventInterface == "UIEvent") {
		event.initUIEvent(type, s.bubbles, s.cancelable, window, s.detail);
	} else if (eventInterface == "MouseEvent") {
		var sx = s.screenX, sy = s.screenY, cx = s.clientX, cy = s.clientY;
		if (s.initTouchEvent && ct && ct.length > 0) {
			var t = ct[0];
			sx = t.screenX;
			sy = t.screenY;
			cx = t.clientX;
			cy = t.clientY;
		}
		event.initMouseEvent(type, s.bubbles, s.cancelable, document.defaultView, s.detail, sx, sy, cx, cy, s.ctrlKey, s.altKey, s.shiftKey, s.metaKey, s.button, s.relatedTarget);
	} else if (eventInterface == "TouchEvent") {
		event.initTouchEvent(type, s.bubbles, s.cancelable, window, s.detail, s.screenX, s.screenY, s.clientX, s.clientY, s.ctrlKey, s.altKey, s.shiftKey, s.metaKey, s.touches, s.targetTouches, ct, s.scale, s.rotation);
	}
	
	return event;
};

})(wink);