var Core = {};

// W3C DOM 2 Events model
if (document.addEventListener)
{
	Core.addEventListener = function(target, type, listener)
	{
		target.addEventListener(type, listener, false);
	};

	Core.removeEventListener = function(target, type, listener)
	{
		target.removeEventListener(type, listener, false);
	};

	Core.preventDefault = function(event)
	{
		event.preventDefault();
	};
	
	Core.stopPropagation = function(event)
	{
		event.stopPropagation();
	};
}

// Internet Explorer Events model
else if (document.attachEvent)
{
	Core.addEventListener = function(target, type, listener)
	{
		if (Core._findListener(target, type, listener) != -1)
		return;

		var listener2 = function()
		{
			var event = window.event;
			if (Function.prototype.call)
			{
				listener.call(target, event);
			}
			else
			{
				target._currentListener = listener;
				target._currentListener(event)
				target._currentListener = null;
			}
		};
	
		target.attachEvent("on" + type, listener2);
		
		var listenerRecord =
		{
			target: target,
			type: type,
			listener: listener,
			listener2: listener2
		};
		
		var targetDocument = target.document || target;
		var targetWindow = targetDocument.parentWindow;
		var listenerId = "l" + Core._listenerCounter++;

		if (!targetWindow._allListeners)
			targetWindow._allListeners = {};
		targetWindow._allListeners[listenerId] = listenerRecord;

		if (!target._listeners) target._listeners = [];
		target._listeners[target._listeners.length] = listenerId;

		if (!targetWindow._unloadListenerAdded)
		{
			targetWindow._unloadListenerAdded = true;
			targetWindow.attachEvent(
				"onunload", Core._removeAllListeners);
		}
	};

	Core.removeEventListener = function(target, type, listener)
	{
		var listenerIndex = Core._findListener(
			target, type, listener);
		if (listenerIndex == -1) return;
		
		var targetDocument = target.document || target;
		var targetWindow = targetDocument.parentWindow;
		var listenerId = target._listeners[listenerIndex];
		var listenerRecord = targetWindow._allListeners[listenerId];

		target.detachEvent("on" + type, listenerRecord.listener2);
		target._listeners.splice(listenerIndex, 1);
		delete targetWindow._allListeners[listenerId];
	};

	Core.preventDefault = function(event)
	{
		event.returnValue = false;
	};

	Core.stopPropagation = function(event)
	{
		event.cancelBubble = true;
	};

	Core._findListener = function(target, type, listener)
	{
		if(!target._listeners) return -1;
		var listeners = target._listeners;
		if (!listeners) return -1;

		var targetDocument = target.document || target;
		var targetWindow = targetDocument.parentWindow;

		for (var i = listeners.length - 1; i >= 0; i--)
		{
			var listenerId = listeners[i];
			var listenerRecord =
				targetWindow._allListeners[listenerId];
			
			if (listenerRecord.type == type && listenerRecord.listener == listener)
			{
				return i;
			}
		}
		
		return -1;
	};

	Core._removeAllListeners = function()
	{
		var targetWindow = this;
		for (id in targetWindow._allListeners)
		{
			var listenerRecord = targetWindow._allListeners[id];
			listenerRecord.target.detachEvent(
				"on" + listenerRecord.type, listenerRecord.listener2);
			delete targetWindow._allListeners[id];
		}
	};
	
	Core._listenerCounter = 0;
}

Core.addClass = function(target, theClass)
{
	if (!Core.hasClass(target, theClass))
	{
		if (target.className == "")
		{
			target.className = theClass;
		}
		else
		{
			target.className += " " + theClass;
		}
	}
};

Core.getElementsByClass = function(theClass)
{
	var elementArray = [];
	if (document.all)
	{
		elementArray = document.all;
	}
	else
	{
		elementArray = document.getElementsByTagName("*");
	}

	var matchedArray = [];
	var pattern = new RegExp("(^| )" + theClass + "( |$)");
	for (var i = 0; i < elementArray.length; i++)
	{
		if (pattern.test(elementArray[i].className))
		{
			matchedArray[matchedArray.length] = elementArray[i];
		}
	}
	return matchedArray;
};

Core.hasClass = function(target, theClass)
{
	var pattern = new RegExp("(^| )" + theClass + "( |$)");
	if (pattern.test(target.className))
	{
		return true;
	}

	return false;
};

Core.removeClass = function(target, theClass)
{
	var pattern = new RegExp("(^| )" + theClass + "( |$)");
	target.className = target.className.replace(pattern, "$1");
	target.className = target.className.replace(/ $/, "");
};

Core.getComputedStyle = function(element, styleProperty)
{
	var computedStyle = null;
	if (typeof element.currentStyle != "undefined")
	{
		computedStyle = element.currentStyle;
	}
	else
	{
		computedStyle =
		document.defaultView.getComputedStyle(element, null);
	}
	return computedStyle[styleProperty];
};

Core.start = function(runnable)
{
	Core.addEventListener(window, "load", runnable.init);
};

Core.getEventObject = function (e) {
	var el;
	if (window.event && window.event.srcElement)
		el = window.event.srcElement;
	if (e && e.target)
		el = e.target;

	return el;
}

if(!Array.indexOf){
	Array.prototype.indexOf = function(obj){
		for(var i=0; i<this.length; i++){
			if(this[i]==obj){
				return i;
			}
		}
		return -1;
	}
}