GZ/nwyj/.svn/pristine/db/dbd918cba2ff9b1b34f30656da2b48afe35e8ed4.svn-base

/*
 * Ext JS Library 2.0 Copyright(c) 2006-2007, Ext JS, LLC. licensing@extjs.com
 * 
 * http://extjs.com/license
 */

/*
 * Copyright (c) 2007, Yahoo! Inc. All rights reserved. Code licensed under the
 * BSD License: http://developer.yahoo.net/yui/license.txt version: 2.2.0
 */
/**
 * The Event Utility provides utilities for managing DOM Events and tools for
 * building event systems
 * 
 * @module event
 * @title Event Utility
 * @namespace YAHOO.util
 * @requires yahoo
 */

// The first instance of Event will win if it is loaded more than once.
// @TODO this needs to be changed so that only the state data that needs to
// be preserved is kept, while methods are overwritten/added as needed.
// This means that the module pattern can't be used.
if (!YAHOO.util.Event) {

	/**
	 * The event utility provides functions to add and remove event listeners,
	 * event cleansing. It also tries to automatically remove listeners it
	 * registers during the unload event.
	 * 
	 * @class Event
	 * @static
	 */
	YAHOO.util.Event = function() {

		/**
		 * True after the onload event has fired
		 * 
		 * @property loadComplete
		 * @type boolean
		 * @static
		 * @private
		 */
		var loadComplete = false;

		/**
		 * Cache of wrapped listeners
		 * 
		 * @property listeners
		 * @type array
		 * @static
		 * @private
		 */
		var listeners = [];

		/**
		 * User-defined unload function that will be fired before all events are
		 * detached
		 * 
		 * @property unloadListeners
		 * @type array
		 * @static
		 * @private
		 */
		var unloadListeners = [];

		/**
		 * Cache of DOM0 event handlers to work around issues with DOM2 events
		 * in Safari
		 * 
		 * @property legacyEvents
		 * @static
		 * @private
		 */
		var legacyEvents = [];

		/**
		 * Listener stack for DOM0 events
		 * 
		 * @property legacyHandlers
		 * @static
		 * @private
		 */
		var legacyHandlers = [];

		/**
		 * The number of times to poll after window.onload. This number is
		 * increased if additional late-bound handlers are requested after the
		 * page load.
		 * 
		 * @property retryCount
		 * @static
		 * @private
		 */
		var retryCount = 0;

		/**
		 * onAvailable listeners
		 * 
		 * @property onAvailStack
		 * @static
		 * @private
		 */
		var onAvailStack = [];

		/**
		 * Lookup table for legacy events
		 * 
		 * @property legacyMap
		 * @static
		 * @private
		 */
		var legacyMap = [];

		/**
		 * Counter for auto id generation
		 * 
		 * @property counter
		 * @static
		 * @private
		 */
		var counter = 0;

		/**
		 * addListener/removeListener can throw errors in unexpected scenarios.
		 * These errors are suppressed, the method returns false, and this
		 * property is set
		 * 
		 * @property lastError
		 * @type Error
		 */
		var lastError = null;

		return {

			/**
			 * The number of times we should look for elements that are not in
			 * the DOM at the time the event is requested after the document has
			 * been loaded. The default is 200@amp;50 ms, so it will poll for 10
			 * seconds or until all outstanding handlers are bound (whichever
			 * comes first).
			 * 
			 * @property POLL_RETRYS
			 * @type int
			 * @static
			 * @final
			 */
			POLL_RETRYS : 200,

			/**
			 * The poll interval in milliseconds
			 * 
			 * @property POLL_INTERVAL
			 * @type int
			 * @static
			 * @final
			 */
			POLL_INTERVAL : 20,

			/**
			 * Element to bind, int constant
			 * 
			 * @property EL
			 * @type int
			 * @static
			 * @final
			 */
			EL : 0,

			/**
			 * Type of event, int constant
			 * 
			 * @property TYPE
			 * @type int
			 * @static
			 * @final
			 */
			TYPE : 1,

			/**
			 * Function to execute, int constant
			 * 
			 * @property FN
			 * @type int
			 * @static
			 * @final
			 */
			FN : 2,

			/**
			 * Function wrapped for scope correction and cleanup, int constant
			 * 
			 * @property WFN
			 * @type int
			 * @static
			 * @final
			 */
			WFN : 3,

			/**
			 * Object passed in by the user that will be returned as a parameter
			 * to the callback, int constant
			 * 
			 * @property OBJ
			 * @type int
			 * @static
			 * @final
			 */
			OBJ : 3,

			/**
			 * Adjusted scope, either the element we are registering the event
			 * on or the custom object passed in by the listener, int constant
			 * 
			 * @property ADJ_SCOPE
			 * @type int
			 * @static
			 * @final
			 */
			ADJ_SCOPE : 4,

			/**
			 * Safari detection is necessary to work around the preventDefault
			 * bug that makes it so you can't cancel a href click from the
			 * handler. Since this function has been used outside of this
			 * utility, it was changed to detect all KHTML browser to be more
			 * friendly towards the non-Safari browsers that share the engine.
			 * Internally, the preventDefault bug detection now uses the webkit
			 * property.
			 * 
			 * @property isSafari
			 * @private
			 * @static
			 * @deprecated
			 */
			isSafari : (/KHTML/gi).test(navigator.userAgent),

			/**
			 * If WebKit is detected, we keep track of the version number of the
			 * engine. Safari 1.3.2 (312.6): 312.8.1 <-- currently the latest
			 * available on Mac OSX 10.3. Safari 2.0.2: 416 <-- hasOwnProperty
			 * introduced Safari 2.0.4: 418 <-- preventDefault fixed (I believe)
			 * Safari 2.0.4 (419.3): 418.9.1 <-- current release
			 * 
			 * http://developer.apple.com/internet/safari/uamatrix.html
			 * 
			 * @property webkit
			 */
			webkit : function() {
				var v = navigator.userAgent.match(/AppleWebKit\/([^ ]*)/);
				if (v && v[1]) {
					return v[1];
				}
				return null;
			}(),

			/**
			 * IE detection needed to properly calculate pageX and pageY.
			 * capabilities checking didn't seem to work because another browser
			 * that does not provide the properties have the values calculated
			 * in a different manner than IE.
			 * 
			 * @property isIE
			 * @private
			 * @static
			 */
			isIE : (!this.webkit && !navigator.userAgent.match(/opera/gi) && navigator.userAgent
					.match(/msie/gi)),

			/**
			 * poll handle
			 * 
			 * @property _interval
			 * @private
			 */
			_interval : null,

			/**
			 * @method startInterval
			 * @static
			 * @private
			 */
			startInterval : function() {
				if (!this._interval) {
					var self = this;
					var callback = function() {
						self._tryPreloadAttach();
					};
					this._interval = setInterval(callback, this.POLL_INTERVAL);
					// this.timeout = setTimeout(callback, i);
				}
			},

			/**
			 * Executes the supplied callback when the item with the supplied id
			 * is found. This is meant to be used to execute behavior as soon as
			 * possible as the page loads. If you use this after the initial
			 * page load it will poll for a fixed time for the element. The
			 * number of times it will poll and the frequency are configurable.
			 * By default it will poll for 10 seconds.
			 * 
			 * @method onAvailable
			 * 
			 * @param {string}
			 *            p_id the id of the element to look for.
			 * @param {function}
			 *            p_fn what to execute when the element is found.
			 * @param {object}
			 *            p_obj an optional object to be passed back as a
			 *            parameter to p_fn.
			 * @param {boolean}
			 *            p_override If set to true, p_fn will execute in the
			 *            scope of p_obj
			 * 
			 * @static
			 */
			onAvailable : function(p_id, p_fn, p_obj, p_override) {
				onAvailStack.push({
							id : p_id,
							fn : p_fn,
							obj : p_obj,
							override : p_override,
							checkReady : false
						});

				retryCount = this.POLL_RETRYS;
				this.startInterval();
			},

			/**
			 * Works the same way as onAvailable, but additionally checks the
			 * state of sibling elements to determine if the content of the
			 * available element is safe to modify.
			 * 
			 * @method onContentReady
			 * 
			 * @param {string}
			 *            p_id the id of the element to look for.
			 * @param {function}
			 *            p_fn what to execute when the element is ready.
			 * @param {object}
			 *            p_obj an optional object to be passed back as a
			 *            parameter to p_fn.
			 * @param {boolean}
			 *            p_override If set to true, p_fn will execute in the
			 *            scope of p_obj
			 * 
			 * @static
			 */
			onContentReady : function(p_id, p_fn, p_obj, p_override) {
				onAvailStack.push({
							id : p_id,
							fn : p_fn,
							obj : p_obj,
							override : p_override,
							checkReady : true
						});

				retryCount = this.POLL_RETRYS;
				this.startInterval();
			},

			/**
			 * Appends an event handler
			 * 
			 * @method addListener
			 * 
			 * @param {Object}
			 *            el The html element to assign the event to
			 * @param {String}
			 *            sType The type of event to append
			 * @param {Function}
			 *            fn The method the event invokes
			 * @param {Object}
			 *            obj An arbitrary object that will be passed as a
			 *            parameter to the handler
			 * @param {boolean}
			 *            override If true, the obj passed in becomes the
			 *            execution scope of the listener
			 * @return {boolean} True if the action was successful or defered,
			 *         false if one or more of the elements could not have the
			 *         listener attached, or if the operation throws an
			 *         exception.
			 * @static
			 */
			addListener : function(el, sType, fn, obj, override) {

				if (!fn || !fn.call) {
					return false;
				}

				// The el argument can be an array of elements or element ids.
				if (this._isValidCollection(el)) {
					var ok = true;
					for (var i = 0, len = el.length; i < len; ++i) {
						ok = this.on(el[i], sType, fn, obj, override) && ok;
					}
					return ok;

				} else if (typeof el == "string") {
					var oEl = this.getEl(el);
					// If the el argument is a string, we assume it is
					// actually the id of the element. If the page is loaded
					// we convert el to the actual element, otherwise we
					// defer attaching the event until onload event fires

					// check to see if we need to delay hooking up the event
					// until after the page loads.
					if (oEl) {
						el = oEl;
					} else {
						// defer adding the event until the element is available
						this.onAvailable(el, function() {
									YAHOO.util.Event.on(el, sType, fn, obj,
											override);
								});

						return true;
					}
				}

				// Element should be an html element or an array if we get
				// here.
				if (!el) {
					return false;
				}

				// we need to make sure we fire registered unload events
				// prior to automatically unhooking them. So we hang on to
				// these instead of attaching them to the window and fire the
				// handles explicitly during our one unload event.
				if ("unload" == sType && obj !== this) {
					unloadListeners[unloadListeners.length] = [el, sType, fn,
							obj, override];
					return true;
				}

				// if the user chooses to override the scope, we use the custom
				// object passed in, otherwise the executing scope will be the
				// HTML element that the event is registered on
				var scope = el;
				if (override) {
					if (override === true) {
						scope = obj;
					} else {
						scope = override;
					}
				}

				// wrap the function so we can return the obj object when
				// the event fires;
				var wrappedFn = function(e) {
					return fn.call(scope, YAHOO.util.Event.getEvent(e), obj);
				};

				var li = [el, sType, fn, wrappedFn, scope];
				var index = listeners.length;
				// cache the listener so we can try to automatically unload
				listeners[index] = li;

				if (this.useLegacyEvent(el, sType)) {
					var legacyIndex = this.getLegacyIndex(el, sType);

					// Add a new dom0 wrapper if one is not detected for this
					// element
					if (legacyIndex == -1 || el != legacyEvents[legacyIndex][0]) {

						legacyIndex = legacyEvents.length;
						legacyMap[el.id + sType] = legacyIndex;

						// cache the signature for the DOM0 event, and
						// include the existing handler for the event, if any
						legacyEvents[legacyIndex] = [el, sType,
								el["on" + sType]];
						legacyHandlers[legacyIndex] = [];

						el["on" + sType] = function(e) {
							YAHOO.util.Event.fireLegacyEvent(YAHOO.util.Event
											.getEvent(e), legacyIndex);
						};
					}

					// add a reference to the wrapped listener to our custom
					// stack of events
					// legacyHandlers[legacyIndex].push(index);
					legacyHandlers[legacyIndex].push(li);

				} else {
					try {
						this._simpleAdd(el, sType, wrappedFn, false);
					} catch (ex) {
						// handle an error trying to attach an event. If it
						// fails
						// we need to clean up the cache
						this.lastError = ex;
						this.removeListener(el, sType, fn);
						return false;
					}
				}

				return true;

			},

			/**
			 * When using legacy events, the handler is routed to this object so
			 * we can fire our custom listener stack.
			 * 
			 * @method fireLegacyEvent
			 * @static
			 * @private
			 */
			fireLegacyEvent : function(e, legacyIndex) {
				var ok = true, le, lh, li, scope, ret;

				lh = legacyHandlers[legacyIndex];
				for (var i = 0, len = lh.length; i < len; ++i) {
					li = lh[i];
					if (li && li[this.WFN]) {
						scope = li[this.ADJ_SCOPE];
						ret = li[this.WFN].call(scope, e);
						ok = (ok && ret);
					}
				}

				// Fire the original handler if we replaced one. We fire this
				// after the other events to keep stopPropagation/preventDefault
				// that happened in the DOM0 handler from touching our DOM2
				// substitute
				le = legacyEvents[legacyIndex];
				if (le && le[2]) {
					le[2](e);
				}

				return ok;
			},

			/**
			 * Returns the legacy event index that matches the supplied
			 * signature
			 * 
			 * @method getLegacyIndex
			 * @static
			 * @private
			 */
			getLegacyIndex : function(el, sType) {
				var key = this.generateId(el) + sType;
				if (typeof legacyMap[key] == "undefined") {
					return -1;
				} else {
					return legacyMap[key];
				}
			},

			/**
			 * Logic that determines when we should automatically use legacy
			 * events instead of DOM2 events. Currently this is limited to old
			 * Safari browsers with a broken preventDefault
			 * 
			 * @method useLegacyEvent
			 * @static
			 * @private
			 */
			useLegacyEvent : function(el, sType) {
				if (this.webkit && ("click" == sType || "dblclick" == sType)) {
					var v = parseInt(this.webkit, 10);
					if (!isNaN(v) && v < 418) {
						return true;
					}
				}
				return false;
			},

			/**
			 * Removes an event handler
			 * 
			 * @method removeListener
			 * 
			 * @param {Object}
			 *            el the html element or the id of the element to assign
			 *            the event to.
			 * @param {String}
			 *            sType the type of event to remove.
			 * @param {Function}
			 *            fn the method the event invokes. If fn is undefined,
			 *            then all event handlers for the type of event are
			 *            removed.
			 * @return {boolean} true if the unbind was successful, false
			 *         otherwise.
			 * @static
			 */
			removeListener : function(el, sType, fn) {
				var i, len;

				// The el argument can be a string
				if (typeof el == "string") {
					el = this.getEl(el);
					// The el argument can be an array of elements or element
					// ids.
				} else if (this._isValidCollection(el)) {
					var ok = true;
					for (i = 0, len = el.length; i < len; ++i) {
						ok = (this.removeListener(el[i], sType, fn) && ok);
					}
					return ok;
				}

				if (!fn || !fn.call) {
					// return false;
					return this.purgeElement(el, false, sType);
				}

				if ("unload" == sType) {

					for (i = 0, len = unloadListeners.length; i < len; i++) {
						var li = unloadListeners[i];
						if (li && li[0] == el && li[1] == sType && li[2] == fn) {
							unloadListeners.splice(i, 1);
							return true;
						}
					}

					return false;
				}

				var cacheItem = null;

				// The index is a hidden parameter; needed to remove it from
				// the method signature because it was tempting users to
				// try and take advantage of it, which is not possible.
				var index = arguments[3];

				if ("undefined" == typeof index) {
					index = this._getCacheIndex(el, sType, fn);
				}

				if (index >= 0) {
					cacheItem = listeners[index];
				}

				if (!el || !cacheItem) {
					return false;
				}

				if (this.useLegacyEvent(el, sType)) {
					var legacyIndex = this.getLegacyIndex(el, sType);
					var llist = legacyHandlers[legacyIndex];
					if (llist) {
						for (i = 0, len = llist.length; i < len; ++i) {
							li = llist[i];
							if (li && li[this.EL] == el
									&& li[this.TYPE] == sType
									&& li[this.FN] == fn) {
								llist.splice(i, 1);
								break;
							}
						}
					}

				} else {
					try {
						this._simpleRemove(el, sType, cacheItem[this.WFN],
								false);
					} catch (ex) {
						this.lastError = ex;
						return false;
					}
				}

				// removed the wrapped handler
				delete listeners[index][this.WFN];
				delete listeners[index][this.FN];
				listeners.splice(index, 1);

				return true;

			},

			/**
			 * Returns the event's target element
			 * 
			 * @method getTarget
			 * @param {Event}
			 *            ev the event
			 * @param {boolean}
			 *            resolveTextNode when set to true the target's parent
			 *            will be returned if the target is a text node.
			 * @deprecated, the text node is now resolved automatically
			 * @return {HTMLElement} the event's target
			 * @static
			 */
			getTarget : function(ev, resolveTextNode) {
				var t = ev.target || ev.srcElement;
				return this.resolveTextNode(t);
			},

			/**
			 * In some cases, some browsers will return a text node inside the
			 * actual element that was targeted. This normalizes the return
			 * value for getTarget and getRelatedTarget.
			 * 
			 * @method resolveTextNode
			 * @param {HTMLElement}
			 *            node node to resolve
			 * @return {HTMLElement} the normized node
			 * @static
			 */
			resolveTextNode : function(node) {
				// if (node && node.nodeName &&
				// "#TEXT" == node.nodeName.toUpperCase()) {
				if (node && 3 == node.nodeType) {
					return node.parentNode;
				} else {
					return node;
				}
			},

			/**
			 * Returns the event's pageX
			 * 
			 * @method getPageX
			 * @param {Event}
			 *            ev the event
			 * @return {int} the event's pageX
			 * @static
			 */
			getPageX : function(ev) {
				var x = ev.pageX;
				if (!x && 0 !== x) {
					x = ev.clientX || 0;

					if (this.isIE) {
						x += this._getScrollLeft();
					}
				}

				return x;
			},

			/**
			 * Returns the event's pageY
			 * 
			 * @method getPageY
			 * @param {Event}
			 *            ev the event
			 * @return {int} the event's pageY
			 * @static
			 */
			getPageY : function(ev) {
				var y = ev.pageY;
				if (!y && 0 !== y) {
					y = ev.clientY || 0;

					if (this.isIE) {
						y += this._getScrollTop();
					}
				}

				return y;
			},

			/**
			 * Returns the pageX and pageY properties as an indexed array.
			 * 
			 * @method getXY
			 * @param {Event}
			 *            ev the event
			 * @return {[x, y]} the pageX and pageY properties of the event
			 * @static
			 */
			getXY : function(ev) {
				return [this.getPageX(ev), this.getPageY(ev)];
			},

			/**
			 * Returns the event's related target
			 * 
			 * @method getRelatedTarget
			 * @param {Event}
			 *            ev the event
			 * @return {HTMLElement} the event's relatedTarget
			 * @static
			 */
			getRelatedTarget : function(ev) {
				var t = ev.relatedTarget;
				if (!t) {
					if (ev.type == "mouseout") {
						t = ev.toElement;
					} else if (ev.type == "mouseover") {
						t = ev.fromElement;
					}
				}

				return this.resolveTextNode(t);
			},

			/**
			 * Returns the time of the event. If the time is not included, the
			 * event is modified using the current time.
			 * 
			 * @method getTime
			 * @param {Event}
			 *            ev the event
			 * @return {Date} the time of the event
			 * @static
			 */
			getTime : function(ev) {
				if (!ev.time) {
					var t = allGetServerTime().getTime();
					try {
						ev.time = t;
					} catch (ex) {
						this.lastError = ex;
						return t;
					}
				}

				return ev.time;
			},

			/**
			 * Convenience method for stopPropagation + preventDefault
			 * 
			 * @method stopEvent
			 * @param {Event}
			 *            ev the event
			 * @static
			 */
			stopEvent : function(ev) {
				this.stopPropagation(ev);
				this.preventDefault(ev);
			},

			/**
			 * Stops event propagation
			 * 
			 * @method stopPropagation
			 * @param {Event}
			 *            ev the event
			 * @static
			 */
			stopPropagation : function(ev) {
				if (ev.stopPropagation) {
					ev.stopPropagation();
				} else {
					ev.cancelBubble = true;
				}
			},

			/**
			 * Prevents the default behavior of the event
			 * 
			 * @method preventDefault
			 * @param {Event}
			 *            ev the event
			 * @static
			 */
			preventDefault : function(ev) {
				if (ev.preventDefault) {
					ev.preventDefault();
				} else {
					ev.returnValue = false;
				}
			},

			/**
			 * Finds the event in the window object, the caller's arguments, or
			 * in the arguments of another method in the callstack. This is
			 * executed automatically for events registered through the event
			 * manager, so the implementer should not normally need to execute
			 * this function at all.
			 * 
			 * @method getEvent
			 * @param {Event}
			 *            e the event parameter from the handler
			 * @return {Event} the event
			 * @static
			 */
			getEvent : function(e) {
				var ev = e || window.event;

				if (!ev) {
					var c = this.getEvent.caller;
					while (c) {
						ev = c.arguments[0];
						if (ev && Event == ev.constructor) {
							break;
						}
						c = c.caller;
					}
				}

				return ev;
			},

			/**
			 * Returns the charcode for an event
			 * 
			 * @method getCharCode
			 * @param {Event}
			 *            ev the event
			 * @return {int} the event's charCode
			 * @static
			 */
			getCharCode : function(ev) {
				return ev.charCode || ev.keyCode || 0;
			},

			/**
			 * Locating the saved event handler data by function ref
			 * 
			 * @method _getCacheIndex
			 * @static
			 * @private
			 */
			_getCacheIndex : function(el, sType, fn) {
				for (var i = 0, len = listeners.length; i < len; ++i) {
					var li = listeners[i];
					if (li && li[this.FN] == fn && li[this.EL] == el
							&& li[this.TYPE] == sType) {
						return i;
					}
				}

				return -1;
			},

			/**
			 * Generates an unique ID for the element if it does not already
			 * have one.
			 * 
			 * @method generateId
			 * @param el
			 *            the element to create the id for
			 * @return {string} the resulting id of the element
			 * @static
			 */
			generateId : function(el) {
				var id = el.id;

				if (!id) {
					id = "yuievtautoid-" + counter;
					++counter;
					el.id = id;
				}

				return id;
			},

			/**
			 * We want to be able to use getElementsByTagName as a collection to
			 * attach a group of events to. Unfortunately, different browsers
			 * return different types of collections. This function tests to
			 * determine if the object is array-like. It will also fail if the
			 * object is an array, but is empty.
			 * 
			 * @method _isValidCollection
			 * @param o
			 *            the object to test
			 * @return {boolean} true if the object is array-like and populated
			 * @static
			 * @private
			 */
			_isValidCollection : function(o) {
				return (o && // o is something
						o.length && // o is indexed
						typeof o != "string" && // o is not a string
						!o.tagName && // o is not an HTML element
						!o.alert && // o is not a window
				typeof o[0] != "undefined");

			},

			/**
			 * @private
			 * @property elCache DOM element cache
			 * @static
			 */
			elCache : {},

			/**
			 * We cache elements bound by id because when the unload event
			 * fires, we can no longer use document.getElementById
			 * 
			 * @method getEl
			 * @static
			 * @private
			 */
			getEl : function(id) {
				return document.getElementById(id);
			},

			/**
			 * Clears the element cache
			 * 
			 * @deprecated Elements are not cached any longer
			 * @method clearCache
			 * @static
			 * @private
			 */
			clearCache : function() {
			},

			/**
			 * hook up any deferred listeners
			 * 
			 * @method _load
			 * @static
			 * @private
			 */
			_load : function(e) {
				loadComplete = true;
				var EU = YAHOO.util.Event;
				// Remove the listener to assist with the IE memory issue, but
				// not
				// for other browsers because FF 1.0x does not like it.
				if (this.isIE) {
					EU._simpleRemove(window, "load", EU._load);
				}
			},

			/**
			 * Polling function that runs before the onload event fires,
			 * attempting to attach to DOM Nodes as soon as they are available
			 * 
			 * @method _tryPreloadAttach
			 * @static
			 * @private
			 */
			_tryPreloadAttach : function() {

				if (this.locked) {
					return false;
				}

				this.locked = true;

				// keep trying until after the page is loaded. We need to
				// check the page load state prior to trying to bind the
				// elements so that we can be certain all elements have been
				// tested appropriately
				var tryAgain = !loadComplete;
				if (!tryAgain) {
					tryAgain = (retryCount > 0);
				}

				// onAvailable
				var notAvail = [];
				for (var i = 0, len = onAvailStack.length; i < len; ++i) {
					var item = onAvailStack[i];
					if (item) {
						var el = this.getEl(item.id);

						if (el) {
							// The element is available, but not necessarily
							// ready
							// @todo verify IE7 compatibility
							// @todo should we test parentNode.nextSibling?
							// @todo re-evaluate global content ready
							if (!item.checkReady || loadComplete
									|| el.nextSibling
									|| (document && document.body)) {

								var scope = el;
								if (item.override) {
									if (item.override === true) {
										scope = item.obj;
									} else {
										scope = item.override;
									}
								}
								item.fn.call(scope, item.obj);
								// delete onAvailStack[i];
								// null out instead of delete for Opera
								onAvailStack[i] = null;
							}
						} else {
							notAvail.push(item);
						}
					}
				}

				retryCount = (notAvail.length === 0) ? 0 : retryCount - 1;

				if (tryAgain) {
					// we may need to strip the nulled out items here
					this.startInterval();
				} else {
					clearInterval(this._interval);
					this._interval = null;
				}

				this.locked = false;

				return true;

			},

			/**
			 * Removes all listeners attached to the given element via
			 * addListener. Optionally, the node's children can also be purged.
			 * Optionally, you can specify a specific type of event to remove.
			 * 
			 * @method purgeElement
			 * @param {HTMLElement}
			 *            el the element to purge
			 * @param {boolean}
			 *            recurse recursively purge this element's children as
			 *            well. Use with caution.
			 * @param {string}
			 *            sType optional type of listener to purge. If left out,
			 *            all listeners will be removed
			 * @static
			 */
			purgeElement : function(el, recurse, sType) {
				var elListeners = this.getListeners(el, sType);
				if (elListeners) {
					for (var i = 0, len = elListeners.length; i < len; ++i) {
						var l = elListeners[i];
						// can't use the index on the changing collection
						// this.removeListener(el, l.type, l.fn, l.index);
						this.removeListener(el, l.type, l.fn);
					}
				}

				if (recurse && el && el.childNodes) {
					for (i = 0, len = el.childNodes.length; i < len; ++i) {
						this.purgeElement(el.childNodes[i], recurse, sType);
					}
				}
			},

			/**
			 * Returns all listeners attached to the given element via
			 * addListener. Optionally, you can specify a specific type of event
			 * to return.
			 * 
			 * @method getListeners
			 * @param el
			 *            {HTMLElement} the element to inspect
			 * @param sType
			 *            {string} optional type of listener to return. If left
			 *            out, all listeners will be returned
			 * @return {Object} the listener. Contains the following fields:
			 *         &nbsp;&nbsp;type: (string) the type of event
			 *         &nbsp;&nbsp;fn: (function) the callback supplied to
			 *         addListener &nbsp;&nbsp;obj: (object) the custom object
			 *         supplied to addListener &nbsp;&nbsp;adjust: (boolean)
			 *         whether or not to adjust the default scope
			 *         &nbsp;&nbsp;index: (int) its position in the Event util
			 *         listener cache
			 * @static
			 */
			getListeners : function(el, sType) {
				var results = [], searchLists;
				if (!sType) {
					searchLists = [listeners, unloadListeners];
				} else if (sType == "unload") {
					searchLists = [unloadListeners];
				} else {
					searchLists = [listeners];
				}

				for (var j = 0; j < searchLists.length; ++j) {
					var searchList = searchLists[j];
					if (searchList && searchList.length > 0) {
						for (var i = 0, len = searchList.length; i < len; ++i) {
							var l = searchList[i];
							if (l && l[this.EL] === el
									&& (!sType || sType === l[this.TYPE])) {
								results.push({
											type : l[this.TYPE],
											fn : l[this.FN],
											obj : l[this.OBJ],
											adjust : l[this.ADJ_SCOPE],
											index : i
										});
							}
						}
					}
				}

				return (results.length) ? results : null;
			},

			/**
			 * Removes all listeners registered by pe.event. Called
			 * automatically during the unload event.
			 * 
			 * @method _unload
			 * @static
			 * @private
			 */
			_unload : function(e) {

				var EU = YAHOO.util.Event, i, j, l, len, index;

				for (i = 0, len = unloadListeners.length; i < len; ++i) {
					l = unloadListeners[i];
					if (l) {
						var scope = window;
						if (l[EU.ADJ_SCOPE]) {
							if (l[EU.ADJ_SCOPE] === true) {
								scope = l[EU.OBJ];
							} else {
								scope = l[EU.ADJ_SCOPE];
							}
						}
						l[EU.FN].call(scope, EU.getEvent(e), l[EU.OBJ]);
						unloadListeners[i] = null;
						l = null;
						scope = null;
					}
				}

				unloadListeners = null;

				if (listeners && listeners.length > 0) {
					j = listeners.length;
					while (j) {
						index = j - 1;
						l = listeners[index];
						if (l) {
							EU.removeListener(l[EU.EL], l[EU.TYPE], l[EU.FN],
									index);
						}
						j = j - 1;
					}
					l = null;

					EU.clearCache();
				}

				for (i = 0, len = legacyEvents.length; i < len; ++i) {
					// dereference the element
					// delete legacyEvents[i][0];
					legacyEvents[i][0] = null;

					// delete the array item
					// delete legacyEvents[i];
					legacyEvents[i] = null;
				}

				legacyEvents = null;

				EU._simpleRemove(window, "unload", EU._unload);

			},

			/**
			 * Returns scrollLeft
			 * 
			 * @method _getScrollLeft
			 * @static
			 * @private
			 */
			_getScrollLeft : function() {
				return this._getScroll()[1];
			},

			/**
			 * Returns scrollTop
			 * 
			 * @method _getScrollTop
			 * @static
			 * @private
			 */
			_getScrollTop : function() {
				return this._getScroll()[0];
			},

			/**
			 * Returns the scrollTop and scrollLeft. Used to calculate the pageX
			 * and pageY in Internet Explorer
			 * 
			 * @method _getScroll
			 * @static
			 * @private
			 */
			_getScroll : function() {
				var dd = document.documentElement, db = document.body;
				if (dd && (dd.scrollTop || dd.scrollLeft)) {
					return [dd.scrollTop, dd.scrollLeft];
				} else if (db) {
					return [db.scrollTop, db.scrollLeft];
				} else {
					return [0, 0];
				}
			},

			/**
			 * Used by old versions of CustomEvent, restored for backwards
			 * compatibility
			 * 
			 * @method regCE
			 * @private
			 */
			regCE : function() {
				// does nothing
			},

			/**
			 * Adds a DOM event directly without the caching, cleanup, scope
			 * adj, etc
			 * 
			 * @method _simpleAdd
			 * @param {HTMLElement}
			 *            el the element to bind the handler to
			 * @param {string}
			 *            sType the type of event handler
			 * @param {function}
			 *            fn the callback to invoke
			 * @param {boolen}
			 *            capture capture or bubble phase
			 * @static
			 * @private
			 */
			_simpleAdd : function() {
				if (window.addEventListener) {
					return function(el, sType, fn, capture) {
						el.addEventListener(sType, fn, (capture));
					};
				} else if (window.attachEvent) {
					return function(el, sType, fn, capture) {
						el.attachEvent("on" + sType, fn);
					};
				} else {
					return function() {
					};
				}
			}(),

			/**
			 * Basic remove listener
			 * 
			 * @method _simpleRemove
			 * @param {HTMLElement}
			 *            el the element to bind the handler to
			 * @param {string}
			 *            sType the type of event handler
			 * @param {function}
			 *            fn the callback to invoke
			 * @param {boolen}
			 *            capture capture or bubble phase
			 * @static
			 * @private
			 */
			_simpleRemove : function() {
				if (window.removeEventListener) {
					return function(el, sType, fn, capture) {
						el.removeEventListener(sType, fn, (capture));
					};
				} else if (window.detachEvent) {
					return function(el, sType, fn) {
						el.detachEvent("on" + sType, fn);
					};
				} else {
					return function() {
					};
				}
			}()
		};

	}();

	(function() {
		var EU = YAHOO.util.Event;

		/**
		 * YAHOO.util.Event.on is an alias for addListener
		 * 
		 * @method on
		 * @see addListener
		 * @static
		 */
		EU.on = EU.addListener;

		// YAHOO.mix(EU, YAHOO.util.EventProvider.prototype);
		// EU.createEvent("DOMContentReady");
		// EU.subscribe("DOMContentReady", EU._load);

		if (document && document.body) {
			EU._load();
		} else {
			// EU._simpleAdd(document, "DOMContentLoaded", EU._load);
			EU._simpleAdd(window, "load", EU._load);
		}
		EU._simpleAdd(window, "unload", EU._unload);
		EU._tryPreloadAttach();
	})();
}

/**
 * The CustomEvent class lets you define events for your application that can be
 * subscribed to by one or more independent component.
 * 
 * @param {String}
 *            type The type of event, which is passed to the callback when the
 *            event fires
 * @param {Object}
 *            oScope The context the event will fire from. "this" will refer to
 *            this object in the callback. Default value: the window object. The
 *            listener can override this.
 * @param {boolean}
 *            silent pass true to prevent the event from writing to the
 *            debugsystem
 * @param {int}
 *            signature the signature that the custom event subscriber will
 *            receive. YAHOO.util.CustomEvent.LIST or
 *            YAHOO.util.CustomEvent.FLAT. The default is
 *            YAHOO.util.CustomEvent.LIST.
 * @namespace YAHOO.util
 * @class CustomEvent
 * @constructor
 */
YAHOO.util.CustomEvent = function(type, oScope, silent, signature) {

	/**
	 * The type of event, returned to subscribers when the event fires
	 * 
	 * @property type
	 * @type string
	 */
	this.type = type;

	/**
	 * The scope the the event will fire from by default. Defaults to the window
	 * obj
	 * 
	 * @property scope
	 * @type object
	 */
	this.scope = oScope || window;

	/**
	 * By default all custom events are logged in the debug build, set silent to
	 * true to disable debug outpu for this event.
	 * 
	 * @property silent
	 * @type boolean
	 */
	this.silent = silent;

	/**
	 * Custom events support two styles of arguments provided to the event
	 * subscribers.
	 * <ul>
	 * <li>YAHOO.util.CustomEvent.LIST:
	 * <ul>
	 * <li>param1: event name</li>
	 * <li>param2: array of arguments sent to fire</li>
	 * <li>param3: <optional> a custom object supplied by the subscriber</li>
	 * </ul>
	 * </li>
	 * <li>YAHOO.util.CustomEvent.FLAT
	 * <ul>
	 * <li>param1: the first argument passed to fire. If you need to pass
	 * multiple parameters, use and array or object literal</li>
	 * <li>param2: <optional> a custom object supplied by the subscriber</li>
	 * </ul>
	 * </li>
	 * </ul>
	 * 
	 * @property signature
	 * @type int
	 */
	this.signature = signature || YAHOO.util.CustomEvent.LIST;

	/**
	 * The subscribers to this event
	 * 
	 * @property subscribers
	 * @type Subscriber[]
	 */
	this.subscribers = [];

	if (!this.silent) {
	}

	var onsubscribeType = "_YUICEOnSubscribe";

	// Only add subscribe events for events that are not generated by
	// CustomEvent
	if (type !== onsubscribeType) {

		/**
		 * Custom events provide a custom event that fires whenever there is a
		 * new subscriber to the event. This provides an opportunity to handle
		 * the case where there is a non-repeating event that has already fired
		 * has a new subscriber.
		 * 
		 * @event subscribeEvent
		 * @type YAHOO.util.CustomEvent
		 * @param {Function}
		 *            fn The function to execute
		 * @param {Object}
		 *            obj An object to be passed along when the event fires
		 * @param {boolean|Object}
		 *            override If true, the obj passed in becomes the execution
		 *            scope of the listener. if an object, that object becomes
		 *            the the execution scope.
		 */
		this.subscribeEvent = new YAHOO.util.CustomEvent(onsubscribeType, this,
				true);

	}
};

/**
 * Subscriber listener sigature constant. The LIST type returns three
 * parameters: the event type, the array of args passed to fire, and the
 * optional custom object
 * 
 * @property YAHOO.util.CustomEvent.LIST
 * @static
 * @type int
 */
YAHOO.util.CustomEvent.LIST = 0;

/**
 * Subscriber listener sigature constant. The FLAT type returns two parameters:
 * the first argument passed to fire and the optional custom object
 * 
 * @property YAHOO.util.CustomEvent.FLAT
 * @static
 * @type int
 */
YAHOO.util.CustomEvent.FLAT = 1;

YAHOO.util.CustomEvent.prototype = {

	/**
	 * Subscribes the caller to this event
	 * 
	 * @method subscribe
	 * @param {Function}
	 *            fn The function to execute
	 * @param {Object}
	 *            obj An object to be passed along when the event fires
	 * @param {boolean|Object}
	 *            override If true, the obj passed in becomes the execution
	 *            scope of the listener. if an object, that object becomes the
	 *            the execution scope.
	 */
	subscribe : function(fn, obj, override) {
		if (this.subscribeEvent) {
			this.subscribeEvent.fire(fn, obj, override);
		}

		this.subscribers.push(new YAHOO.util.Subscriber(fn, obj, override));
	},

	/**
	 * Unsubscribes subscribers.
	 * 
	 * @method unsubscribe
	 * @param {Function}
	 *            fn The subscribed function to remove, if not supplied all will
	 *            be removed
	 * @param {Object}
	 *            obj The custom object passed to subscribe. This is optional,
	 *            but if supplied will be used to disambiguate multiple
	 *            listeners that are the same (e.g., you subscribe many object
	 *            using a function that lives on the prototype)
	 * @return {boolean} True if the subscriber was found and detached.
	 */
	unsubscribe : function(fn, obj) {

		if (!fn) {
			return this.unsubscribeAll();
		}

		var found = false;
		for (var i = 0, len = this.subscribers.length; i < len; ++i) {
			var s = this.subscribers[i];
			if (s && s.contains(fn, obj)) {
				this._delete(i);
				found = true;
			}
		}

		return found;
	},

	/**
	 * Notifies the subscribers. The callback functions will be executed from
	 * the scope specified when the event was created, and with the following
	 * parameters:
	 * <ul>
	 * <li>The type of event</li>
	 * <li>All of the arguments fire() was executed with as an array</li>
	 * <li>The custom object (if any) that was passed into the subscribe()
	 * method</li>
	 * </ul>
	 * 
	 * @method fire
	 * @param {Object*}
	 *            arguments an arbitrary set of parameters to pass to the
	 *            handler.
	 * @return {boolean} false if one of the subscribers returned false, true
	 *         otherwise
	 */
	fire : function() {
		var len = this.subscribers.length;
		if (!len && this.silent) {
			return true;
		}

		var args = [], ret = true, i;

		for (i = 0; i < arguments.length; ++i) {
			args.push(arguments[i]);
		}

		var argslength = args.length;

		if (!this.silent) {
		}

		for (i = 0; i < len; ++i) {
			var s = this.subscribers[i];
			if (s) {
				if (!this.silent) {
				}

				var scope = s.getScope(this.scope);

				if (this.signature == YAHOO.util.CustomEvent.FLAT) {
					var param = null;
					if (args.length > 0) {
						param = args[0];
					}
					ret = s.fn.call(scope, param, s.obj);
				} else {
					ret = s.fn.call(scope, this.type, args, s.obj);
				}
				if (false === ret) {
					if (!this.silent) {
					}

					// break;
					return false;
				}
			}
		}

		return true;
	},

	/**
	 * Removes all listeners
	 * 
	 * @method unsubscribeAll
	 * @return {int} The number of listeners unsubscribed
	 */
	unsubscribeAll : function() {
		for (var i = 0, len = this.subscribers.length; i < len; ++i) {
			this._delete(len - 1 - i);
		}

		return i;
	},

	/**
	 * @method _delete
	 * @private
	 */
	_delete : function(index) {
		var s = this.subscribers[index];
		if (s) {
			delete s.fn;
			delete s.obj;
		}

		// delete this.subscribers[index];
		this.subscribers.splice(index, 1);
	},

	/**
	 * @method toString
	 */
	toString : function() {
		return "CustomEvent: " + "'" + this.type + "', " + "scope: "
				+ this.scope;

	}
};

// ///////////////////////////////////////////////////////////////////

/**
 * Stores the subscriber information to be used when the event fires.
 * 
 * @param {Function}
 *            fn The function to execute
 * @param {Object}
 *            obj An object to be passed along when the event fires
 * @param {boolean}
 *            override If true, the obj passed in becomes the execution scope of
 *            the listener
 * @class Subscriber
 * @constructor
 */
YAHOO.util.Subscriber = function(fn, obj, override) {

	/**
	 * The callback that will be execute when the event fires
	 * 
	 * @property fn
	 * @type function
	 */
	this.fn = fn;

	/**
	 * An optional custom object that will passed to the callback when the event
	 * fires
	 * 
	 * @property obj
	 * @type object
	 */
	this.obj = obj || null;

	/**
	 * The default execution scope for the event listener is defined when the
	 * event is created (usually the object which contains the event). By
	 * setting override to true, the execution scope becomes the custom object
	 * passed in by the subscriber. If override is an object, that object
	 * becomes the scope.
	 * 
	 * @property override
	 * @type boolean|object
	 */
	this.override = override;

};

/**
 * Returns the execution scope for this listener. If override was set to true
 * the custom obj will be the scope. If override is an object, that is the
 * scope, otherwise the default scope will be used.
 * 
 * @method getScope
 * @param {Object}
 *            defaultScope the scope to use if this listener does not override
 *            it.
 */
YAHOO.util.Subscriber.prototype.getScope = function(defaultScope) {
	if (this.override) {
		if (this.override === true) {
			return this.obj;
		} else {
			return this.override;
		}
	}
	return defaultScope;
};

/**
 * Returns true if the fn and obj match this objects properties. Used by the
 * unsubscribe method to match the right subscriber.
 * 
 * @method contains
 * @param {Function}
 *            fn the function to execute
 * @param {Object}
 *            obj an object to be passed along when the event fires
 * @return {boolean} true if the supplied arguments match this subscriber's
 *         signature.
 */
YAHOO.util.Subscriber.prototype.contains = function(fn, obj) {
	if (obj) {
		return (this.fn == fn && this.obj == obj);
	} else {
		return (this.fn == fn);
	}
};

/**
 * @method toString
 */
YAHOO.util.Subscriber.prototype.toString = function() {
	return "Subscriber { obj: " + (this.obj || "") + ", override: "
			+ (this.override || "no") + " }";
};

/**
 * EventProvider is designed to be used with YAHOO.augment to wrap CustomEvents
 * in an interface that allows events to be subscribed to and fired by name.
 * This makes it possible for implementing code to subscribe to an event that
 * either has not been created yet, or will not be created at all.
 * 
 * @Class EventProvider
 */
YAHOO.util.EventProvider = function() {
};

YAHOO.util.EventProvider.prototype = {

	/**
	 * Private storage of custom events
	 * 
	 * @property __yui_events
	 * @type Object[]
	 * @private
	 */
	__yui_events : null,

	/**
	 * Private storage of custom event subscribers
	 * 
	 * @property __yui_subscribers
	 * @type Object[]
	 * @private
	 */
	__yui_subscribers : null,

	/**
	 * Subscribe to a CustomEvent by event type
	 * 
	 * @method subscribe
	 * @param p_type
	 *            {string} the type, or name of the event
	 * @param p_fn
	 *            {function} the function to exectute when the event fires
	 * @param p_obj
	 * @param p_obj
	 *            {Object} An object to be passed along when the event fires
	 * @param p_override
	 *            {boolean} If true, the obj passed in becomes the execution
	 *            scope of the listener
	 */
	subscribe : function(p_type, p_fn, p_obj, p_override) {

		this.__yui_events = this.__yui_events || {};
		var ce = this.__yui_events[p_type];

		if (ce) {
			ce.subscribe(p_fn, p_obj, p_override);
		} else {
			this.__yui_subscribers = this.__yui_subscribers || {};
			var subs = this.__yui_subscribers;
			if (!subs[p_type]) {
				subs[p_type] = [];
			}
			subs[p_type].push({
						fn : p_fn,
						obj : p_obj,
						override : p_override
					});
		}
	},

	/**
	 * Unsubscribes one or more listeners the from the specified event
	 * 
	 * @method unsubscribe
	 * @param p_type
	 *            {string} The type, or name of the event
	 * @param p_fn
	 *            {Function} The subscribed function to unsubscribe, if not
	 *            supplied, all subscribers will be removed.
	 * @param p_obj
	 *            {Object} The custom object passed to subscribe. This is
	 *            optional, but if supplied will be used to disambiguate
	 *            multiple listeners that are the same (e.g., you subscribe many
	 *            object using a function that lives on the prototype)
	 * @return {boolean} true if the subscriber was found and detached.
	 */
	unsubscribe : function(p_type, p_fn, p_obj) {
		this.__yui_events = this.__yui_events || {};
		var ce = this.__yui_events[p_type];
		if (ce) {
			return ce.unsubscribe(p_fn, p_obj);
		} else {
			return false;
		}
	},

	/**
	 * Removes all listeners from the specified event
	 * 
	 * @method unsubscribeAll
	 * @param p_type
	 *            {string} The type, or name of the event
	 */
	unsubscribeAll : function(p_type) {
		return this.unsubscribe(p_type);
	},

	/**
	 * Creates a new custom event of the specified type. If a custom event by
	 * that name already exists, it will not be re-created. In either case the
	 * custom event is returned.
	 * 
	 * @method createEvent
	 * 
	 * @param p_type
	 *            {string} the type, or name of the event
	 * @param p_config
	 *            {object} optional config params. Valid properties are:
	 * 
	 * <ul>
	 * <li> scope: defines the default execution scope. If not defined the
	 * default scope will be this instance. </li>
	 * <li> silent: if true, the custom event will not generate log messages.
	 * This is false by default. </li>
	 * <li> onSubscribeCallback: specifies a callback to execute when the event
	 * has a new subscriber. This will fire immediately for each queued
	 * subscriber if any exist prior to the creation of the event. </li>
	 * </ul>
	 * 
	 * @return {CustomEvent} the custom event
	 * 
	 */
	createEvent : function(p_type, p_config) {

		this.__yui_events = this.__yui_events || {};
		var opts = p_config || {};
		var events = this.__yui_events;

		if (events[p_type]) {
		} else {

			var scope = opts.scope || this;
			var silent = opts.silent || null;

			var ce = new YAHOO.util.CustomEvent(p_type, scope, silent,
					YAHOO.util.CustomEvent.FLAT);
			events[p_type] = ce;

			if (opts.onSubscribeCallback) {
				ce.subscribeEvent.subscribe(opts.onSubscribeCallback);
			}

			this.__yui_subscribers = this.__yui_subscribers || {};
			var qs = this.__yui_subscribers[p_type];

			if (qs) {
				for (var i = 0; i < qs.length; ++i) {
					ce.subscribe(qs[i].fn, qs[i].obj, qs[i].override);
				}
			}
		}

		return events[p_type];
	},

	/**
	 * Fire a custom event by name. The callback functions will be executed from
	 * the scope specified when the event was created, and with the following
	 * parameters:
	 * <ul>
	 * <li>The first argument fire() was executed with</li>
	 * <li>The custom object (if any) that was passed into the subscribe()
	 * method</li>
	 * </ul>
	 * 
	 * @method fireEvent
	 * @param p_type
	 *            {string} the type, or name of the event
	 * @param arguments
	 *            {Object*} an arbitrary set of parameters to pass to the
	 *            handler.
	 * @return {boolean} the return value from CustomEvent.fire, or null if the
	 *         custom event does not exist.
	 */
	fireEvent : function(p_type, arg1, arg2, etc) {

		this.__yui_events = this.__yui_events || {};
		var ce = this.__yui_events[p_type];

		if (ce) {
			var args = [];
			for (var i = 1; i < arguments.length; ++i) {
				args.push(arguments[i]);
			}
			return ce.fire.apply(ce, args);
		} else {
			return null;
		}
	},

	/**
	 * Returns true if the custom event of the provided type has been created
	 * with createEvent.
	 * 
	 * @method hasEvent
	 * @param type
	 *            {string} the type, or name of the event
	 */
	hasEvent : function(type) {
		if (this.__yui_events) {
			if (this.__yui_events[type]) {
				return true;
			}
		}
		return false;
	}

};

/**
 * KeyListener is a utility that provides an easy interface for listening for
 * keydown/keyup events fired against DOM elements.
 * 
 * @namespace YAHOO.util
 * @class KeyListener
 * @constructor
 * @param {HTMLElement}
 *            attachTo The element or element ID to which the key event should
 *            be attached
 * @param {String}
 *            attachTo The element or element ID to which the key event should
 *            be attached
 * @param {Object}
 *            keyData The object literal representing the key(s) to detect.
 *            Possible attributes are shift(boolean), alt(boolean),
 *            ctrl(boolean) and keys(either an int or an array of ints
 *            representing keycodes).
 * @param {Function}
 *            handler The CustomEvent handler to fire when the key event is
 *            detected
 * @param {Object}
 *            handler An object literal representing the handler.
 * @param {String}
 *            event Optional. The event (keydown or keyup) to listen for.
 *            Defaults automatically to keydown.
 */
YAHOO.util.KeyListener = function(attachTo, keyData, handler, event) {
	if (!attachTo) {
	} else if (!keyData) {
	} else if (!handler) {
	}

	if (!event) {
		event = YAHOO.util.KeyListener.KEYDOWN;
	}

	/**
	 * The CustomEvent fired internally when a key is pressed
	 * 
	 * @event keyEvent
	 * @private
	 * @param {Object}
	 *            keyData The object literal representing the key(s) to detect.
	 *            Possible attributes are shift(boolean), alt(boolean),
	 *            ctrl(boolean) and keys(either an int or an array of ints
	 *            representing keycodes).
	 */
	var keyEvent = new YAHOO.util.CustomEvent("keyPressed");

	/**
	 * The CustomEvent fired when the KeyListener is enabled via the enable()
	 * function
	 * 
	 * @event enabledEvent
	 * @param {Object}
	 *            keyData The object literal representing the key(s) to detect.
	 *            Possible attributes are shift(boolean), alt(boolean),
	 *            ctrl(boolean) and keys(either an int or an array of ints
	 *            representing keycodes).
	 */
	this.enabledEvent = new YAHOO.util.CustomEvent("enabled");

	/**
	 * The CustomEvent fired when the KeyListener is disabled via the disable()
	 * function
	 * 
	 * @event disabledEvent
	 * @param {Object}
	 *            keyData The object literal representing the key(s) to detect.
	 *            Possible attributes are shift(boolean), alt(boolean),
	 *            ctrl(boolean) and keys(either an int or an array of ints
	 *            representing keycodes).
	 */
	this.disabledEvent = new YAHOO.util.CustomEvent("disabled");

	if (typeof attachTo == 'string') {
		attachTo = document.getElementById(attachTo);
	}

	if (typeof handler == 'function') {
		keyEvent.subscribe(handler);
	} else {
		keyEvent.subscribe(handler.fn, handler.scope, handler.correctScope);
	}

	/**
	 * Handles the key event when a key is pressed.
	 * 
	 * @method handleKeyPress
	 * @param {DOMEvent}
	 *            e The keypress DOM event
	 * @param {Object}
	 *            obj The DOM event scope object
	 * @private
	 */
	function handleKeyPress(e, obj) {
		if (!keyData.shift) {
			keyData.shift = false;
		}
		if (!keyData.alt) {
			keyData.alt = false;
		}
		if (!keyData.ctrl) {
			keyData.ctrl = false;
		}

		// check held down modifying keys first
		if (e.shiftKey == keyData.shift && e.altKey == keyData.alt
				&& e.ctrlKey == keyData.ctrl) { // if we pass this, all
												// modifiers match

			var dataItem;
			var keyPressed;

			if (keyData.keys instanceof Array) {
				for (var i = 0; i < keyData.keys.length; i++) {
					dataItem = keyData.keys[i];

					if (dataItem == e.charCode) {
						keyEvent.fire(e.charCode, e);
						break;
					} else if (dataItem == e.keyCode) {
						keyEvent.fire(e.keyCode, e);
						break;
					}
				}
			} else {
				dataItem = keyData.keys;
				if (dataItem == e.charCode) {
					keyEvent.fire(e.charCode, e);
				} else if (dataItem == e.keyCode) {
					keyEvent.fire(e.keyCode, e);
				}
			}
		}
	}

	/**
	 * Enables the KeyListener by attaching the DOM event listeners to the
	 * target DOM element
	 * 
	 * @method enable
	 */
	this.enable = function() {
		if (!this.enabled) {
			YAHOO.util.Event.addListener(attachTo, event, handleKeyPress);
			this.enabledEvent.fire(keyData);
		}
		/**
		 * Boolean indicating the enabled/disabled state of the Tooltip
		 * 
		 * @property enabled
		 * @type Boolean
		 */
		this.enabled = true;
	};

	/**
	 * Disables the KeyListener by removing the DOM event listeners from the
	 * target DOM element
	 * 
	 * @method disable
	 */
	this.disable = function() {
		if (this.enabled) {
			YAHOO.util.Event.removeListener(attachTo, event, handleKeyPress);
			this.disabledEvent.fire(keyData);
		}
		this.enabled = false;
	};

	/**
	 * Returns a String representation of the object.
	 * 
	 * @method toString
	 * @return {String} The string representation of the KeyListener
	 */
	this.toString = function() {
		return "KeyListener [" + keyData.keys + "] " + attachTo.tagName
				+ (attachTo.id ? "[" + attachTo.id + "]" : "");
	};

};

/**
 * Constant representing the DOM "keydown" event.
 * 
 * @property YAHOO.util.KeyListener.KEYDOWN
 * @static
 * @final
 * @type String
 */
YAHOO.util.KeyListener.KEYDOWN = "keydown";

/**
 * Constant representing the DOM "keyup" event.
 * 
 * @property YAHOO.util.KeyListener.KEYUP
 * @static
 * @final
 * @type String
 */
YAHOO.util.KeyListener.KEYUP = "keyup";
YAHOO.register("event", YAHOO.util.Event, {
			version : "2.2.0",
			build : "127"
		});