/*

Copyright (c) 2009, Yahoo! Inc. All rights reserved.

Code licensed under the BSD License:

http://developer.yahoo.net/yui/license.txt

version: 3.0.0

build: 1549

*/

YUI.add('event-mouseenter', function(Y) {

/**

 * Adds support for mouseenter/mouseleave events

 * @module event

 * @submodule event-mouseenter

 */

var Event = Y.Event,

	Lang = Y.Lang,

	plugins = Y.Env.evt.plugins,

	listeners = {},

	eventConfig = {

    	on: function(type, fn, el) {

		    var args = Y.Array(arguments, 0, true),	    

				element = el,

				availHandle;

			if (Lang.isString(el)) {

				//	Need to use Y.all because if el is a string it could be a 

				//	selector that returns a NodeList

				element = Y.all(el);

				if (element.size() === 0) { // Not found, check using onAvailable

		            availHandle = Event.onAvailable(el, function() {

		                availHandle.handle = Y.on.apply(Y, args);

		            }, Event, true, false);

					return availHandle;

				}

			}

	        var sDOMEvent = (type === "mouseenter") ? "mouseover" : "mouseout",

				//	The name of the custom event

				sEventName = type + ":" + Y.stamp(element) + sDOMEvent,

				listener = listeners[sEventName],

				domEventHandle,

				ceHandle,

				nListeners;

			//	Bind an actual DOM event listener that will call the 

			//	the custom event				

			if (!listener) {

				domEventHandle = Y.on(sDOMEvent, Y.rbind(Event._fireMouseEnter, Y, sEventName), element);

				//	Hook into the _delete method for the Custom Event wrapper of this

				//	DOM Event in order to clean up the 'listeners' map and unsubscribe

				//	the associated Custom Event listeners fired by this DOM event

				//	listener if/when the user calls "purgeElement" OR removes all 

				//	listeners of the Custom Event.

				Y.after(function (sub) {

					if (domEventHandle.sub == sub) {

						//	Delete this event from the map of known mouseenter 

						//	and mouseleave listeners

						delete listeners[sEventName];

						Y.log("DOM event listener associated with the " + sEventName + " Custom Event removed.  Removing all " + sEventName + " listeners.", "info", "Event");

						//	Unsubscribe all listeners of the Custom Event fired 

						//	by this DOM event.

						Y.detachAll(sEventName);

					}

				}, domEventHandle.evt, "_delete");

				listener = {};				

				listener.handle = domEventHandle;				

				listeners[sEventName] = listener;

			}

			nListeners = listener.count;

			listener.count = nListeners ? (nListeners + 1) : 1;

	        args[0] = sEventName;

	        // Remove the element from the args

			args.splice(2, 1);

	        // Subscribe to the custom event

	        ceHandle = Y.on.apply(Y, args);

			//	Hook into the detach method of the handle in order to clean up the 

			//	'listeners' map and remove the associated DOM event handler 

			//	responsible for firing this Custom Event if all listener for this 

			//	event have been removed.

			Y.after(function () {

				listener.count = (listener.count - 1);

				if (listener.count === 0) {

					Y.log("No more listeners for the " + sEventName + " Custom Event.  Removing its associated DOM event listener.", "info", "Event");

					listener.handle.detach();

				}

			}, ceHandle, "detach");	

			return ceHandle;

	    }

	};

Event._fireMouseEnter = function (e, eventName) {

	var relatedTarget = e.relatedTarget,

		currentTarget = e.currentTarget;

	if (currentTarget !== relatedTarget && 

		!currentTarget.contains(relatedTarget)) {

		Y.publish(eventName, {

               contextFn: function() {

                   return currentTarget;

               }

           });			

		Y.fire(eventName, e);

	}

};	

/**

 * Sets up a "mouseenter" listener—a listener that is called the first time 

 * the user's mouse enters the specified element(s).

 * 

 * @event mouseenter

 * @param type {string} "mouseenter"

 * @param fn {function} The method the event invokes.

 * @param el {string|node} The element(s) to assign the listener to.

 * @param spec {string} Optional.  String representing a selector that must 

 * match the target of the event in order for the listener to be called.

 * @return {EventHandle} the detach handle

 * @for YUI

 */

plugins.mouseenter = eventConfig;

/**

* Sets up a "mouseleave" listener—a listener that is called the first time 

* the user's mouse leaves the specified element(s).

* 

* @event mouseleave

* @param type {string} "mouseleave"

* @param fn {function} The method the event invokes.

* @param el {string|node} The element(s) to assign the listener to.

* @param spec {string} Optional.  String representing a selector that must 

* match the target of the event in order for the listener to be called.

* @return {EventHandle} the detach handle

* @for YUI

 */

plugins.mouseleave = eventConfig;

}, '3.0.0' ,{requires:['node-base']});