$event

/*----------------------------------------------------------------------------*-
Function:
	$event, $event.add
Params:
	domEvent - Name of the event to attach to.
	source (optional) - Element to attach to, default 'document'.
	func - Function to call on the event.
Return:
	-
Notes:
	Attach a function to an event in a cross-browser way.  Overrides the IE
	thing of passing 'this' as the window object instead of the object that
	fired the event.  Unfortunately this breaks removeEvent.
-*----------------------------------------------------------------------------*/

$event = function (domEvent, source, func)
{
	if (window.addEventListener)
	{
		$event = $event._addEventListener;
	}
	else
	{
		/*if (window.attachEvent)
		{
		}
		else
		{*/
			$event = $event._eventHandler;
		/*}*/
	}
	return $event(domEvent, source, func);
}

$event.add = $event;

/*----------------------------------------------------------------------------*-
Function:
	$event._eventHandler
Params:
	domEvent - Name of the event to attach to.
	source (optional) - Element to attach to, default 'document'.
	func - Function to call on the event.
Return:
	-
Notes:
	$event implementation in browsers with no addEventListener.  Detects if an
	event has already been manually applied to an element using HTML based
	listeners (i.e. onevent='code') and preserves them, calling them first as
	with addEventListener.
-*----------------------------------------------------------------------------*/

$event._eventHandler = function (domEvent, source, func)
{
	if (!func)
	{
		if (!source)
		{
			return;
		}
		func = source;
		source = document;
	}
	// Check if an event has been applied to this already
	domEvent = domEvent.substring(0, 2) == 'on' ? domEvent : 'on' + domEvent;
	var
		ev = source[domEvent];
	if (ev)
	{
		// Already has something registered
		if (!ev._has$event)
		{
			// Has a function, but not one of ours
			var
				old = ev;
			ev = function (event)
			{
				event = event || window.event;
				var
					c = ev._calls,
					i = -1,
					j = c.length,
					oldStop = event.stopPropagation,
					ret = false;
				event.cancelBubble = false;
				event.stopPropagation = function ()
				{
					event.cancelBubble = true;
				}
				if (old.call(source, event))
				{
					ret = true;
				}
				while (++i < j)
				{
					if (c[i])
					{
						if (c[i].call(source, event))
						{
							ret = true;
						}
					}
				}
				if (oldStop && event.cancelBubble)
				{
					oldStop();
				}
				return ret;
			}
			ev._calls = [];
		}
	}
	else
	{
		// Nothing registered
		ev = function (event)
		{
			event = event || window.event;
			var
				c = ev._calls,
				i = -1,
				j = c.length,
				oldStop = event.stopPropagation,
				ret = false;
			event.cancelBubble = false;
			event.stopPropagation = function ()
			{
				event.cancelBubble = true;
			}
			while (++i < j)
			{
				if (c[i])
				{
					if (c[i].call(source, event))
					{
						ret = true;
					}
				}
			}
			if (oldStop && event.cancelBubble)
			{
				oldStop();
			}
			return ret;
		}
		ev._calls = [];
	}
	ev._calls[ev._calls.length] = func;
	ev._has$event = true;
	source[domEvent] = ev;
}

/*----------------------------------------------------------------------------*-
Function:
	$event._addEventListener
Params:
	domEvent - Name of the event to attach to.
	source (optional) - Element to attach to, default 'document'.
	func - Function to call on the event.
Return:
	-
Notes:
	$event implementation in browsers with addEventListener.
-*----------------------------------------------------------------------------*/

$event._addEventListener = function (domEvent, source, func)
{
	if (!func)
	{
		if (!source)
		{
			return;
		}
		func = source;
		source = document;
	}
	var
		nf;
	if (!func._$_event_$_handler_$_)
	{
		func._$_event_$_handler_$_ = [];
	}
	if (!func._$_event_$_handler_$_[domEvent])
	{
		// Create an annonymous function to correctly pass the variables
		nf = function (event)
		{
			event = event || window.event;
			if (!func.call(source, event))
			{
				// Add handling for returning false
				if (event.preventDefault)
				{
					event.preventDefault();
				}
				else
				{
					event.returnValue = false;
				}
				return false;
			}
			return true;
		}
		func._$_event_$_handler_$_[domEvent] = nf;
	}
	else
	{
		nf = func._$_event_$_handler_$_[domEvent];
	}
	// Strip 'on'
	domEvent = domEvent.substring(0, 2) == 'on' ? domEvent.substring(2) : domEvent;
	source.addEventListener(domEvent, nf, false);
}