// [[ 0. Portable event handler registration functions for IE DOM2. ]]
var Handler = {};

if ( document.addEventListener )
	{
		Handler.add = function(element, eventType, handler)
			{ element.addEventListener(eventType, handler, false); };

		Handler.remove = function(element, eventType, handler)
			{ element.removeEventListener(eventType, handler, false); };
	}
else if ( document.attachEvent )
	{
		Handler.add = function(element, eventType, handler)
			{
				if ( Handler._find(element, eventType, handler) != -1 ) return;

				var wrappedHandler = function(e)
					{
						if ( !e ) { e = window.event; }

						var event =
						{
							_event: e,
							type: e.type,
							target: e.srcElement,
							currentTarget: element,
							relatedTarget: ( e.fromElement ? e.fromElement : e.toElement ),
							eventPhase: ( e.srcElement == element ? 2 : 3 ),

							clientX: e.clientX,
							clientY: e.clientY,
							screenX: e.screenX,
							screenY: e.screenY,

							altKey: e.altKey,
							ctrlKey: e.ctrlKey,
							shiftKey: e.shiftKey,
							charCode: e.keyCode,

							stopPropagation: function() {this._event.cancelBubble = true;},
							preventDefault: function() {this._event.returnValue = false;}
						}

						if ( Function.prototype.call )
							{ handler.call(element, event); }
						else
							{
								element._currentHandler = handler;
								element._currentHandler(event);
								element._currentHandler = null;
							}
					};

				element.attachEvent('on'+ eventType, wrappedHandler);

				var h =
				{
					element: element,
					eventType: eventType,
					handler: handler,
					wrappedHandler: wrappedHandler
				};

				var d = element.document || element;
				var w = d.parentWindow;

				var id = Handler._uid();
				if ( !w._allHandlers ) w._allHandlers = {};
				w._allHandlers[id] = h;

				if ( !element._handlers ) element._handlers = [];
				element._handlers.push(id);

				if ( !w._onunloadHandlerRegistered )
					{
						w._onunloadHandlerRegistered = true;
						w.attachEvent("onunload", Handler._removeAllHandlers);
					}
			};

		Handler.remove = function(element, eventType, handler)
			{
				var i = Handler._find(element, eventType, handler);
				if ( i == -1 ) return;

				var d = element.document || element;
				var w = d.parentWindow;

				var handlerId = element._handlers[i];
				var h = w._allHandlers[handlerId];
				element.detachEvent("on" + eventType, h.wrappedHandler);
				element._handlers.splice(i, 1);
				delete w._allHandlers[handlerId];
			};

		Handler._find = function(element, eventType, handler)
			{
				var handlers = element._handlers;
				if ( !handlers ) return -1;

				var d = element.document || element;
				var w = d.parentWindow;

				for( var i = handlers.length - 1; i >= 0; i-- )
					{
						var handlerId = handlers[i];
						var h = w._allHandlers[handlerId];
						if ( h.eventType == eventType && h.handler == handler )
							{ return i; }
					}
				return -1;
			};

		Handler._removeAllHandlers = function()
			{
				var w = this;

				for( id in w._allHandlers )
					{
						var h = w._allHandlers[id];
						h.element.detachEvent('on'+ h.eventType, h.wrappedHandler);
						delete w._allHandlers[id];
					}
			}

		Handler._counter = 0;
		Handler._uid = function()
			{ return('h'+ Handler._counter++); };
	}