var Overlay = {

	display : function()
	{
		if(!Overlay.div)
		{
		
			Overlay.div = document.createElement("div");
			Overlay.div.id = "overlay";
			Overlay.div.onclick = function()
			{
				Overlay.remove();
			}
			var theContainer = document.getElementById("container");
			theContainer.parentNode.appendChild(Overlay.div);
			Overlay.calculateDivSize();
			
			Overlay.div.window = document.createElement("div");
			Overlay.div.window.id = "window";
			Overlay.div.window.style.visible = "hidden";
			Overlay.div.appendChild(Overlay.div.window);
			//Overlay.calculateWindowPosition();
			
		}
	}
	,
	remove : function()
	{
		if(Overlay.div)
		{
			var theContainer = document.getElementById("container");
			theContainer.parentNode.removeChild(Overlay.div);
			Overlay.div = null;
		}
	}
	,
	addContent : function(html)
	{
		Overlay.div.window.innerHTML += html;			
		Overlay.calculateWindowPosition();
		Overlay.div.window.style.visible = "visible";
	}
	,
	calculateWindowPosition : function()
	{
		if(Overlay.div)
		{	
			var pagesize = TB_getPageSize();	
			var arrayPageScroll = TB_getPageScrollTop();
			var height = Overlay.div.window.offsetHeight;
			var top = (arrayPageScroll[1] + (pagesize[1]-height)/2);
			Overlay.div.window.style.marginTop = top + "px";
		}
	}
	,
	calculateDivSize : function()
	{
		if(Overlay.div)
		{	
			Overlay.setSize(0,0);
			if (window.innerHeight && window.scrollMaxY || window.innerWidth && window.scrollMaxX) 
			{	
				height = window.innerHeight + window.scrollMaxY;
				width = window.innerWidth + window.scrollMaxX;
				var deff = document.documentElement;
				var wff = (deff&&deff.clientWidth) || document.body.clientWidth || window.innerWidth || self.innerWidth;
				var hff = (deff&&deff.clientHeight) || document.body.clientHeight || window.innerHeight || self.innerHeight;
				height -= (window.innerHeight - hff);				
				width -= (window.innerWidth - wff);
			} else if (document.body.scrollHeight > document.body.offsetHeight || document.body.scrollWidth > document.body.offsetWidth){ // all but Explorer Mac
				height = document.body.scrollHeight;
				width = document.body.scrollWidth;
			} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
				height = document.body.offsetHeight;
				width = document.body.offsetWidth;
		  	}
			Overlay.setSize(width, height);
		}
	}
	,
	setSize : function(width, height)
	{
		if(Overlay.div)
		{
			Overlay.div.style.width = width + "px";
			Overlay.div.style.height = height + "px";
		}
	}
	
	
}

function TB_position() {
	var pagesize = TB_getPageSize();	
	var arrayPageScroll = TB_getPageScrollTop();
	var style = {width: TB_WIDTH, left: (arrayPageScroll[0] + (pagesize[0] - TB_WIDTH)/2), top: (arrayPageScroll[1] + (pagesize[1]-TB_HEIGHT)/2)};
	$("#TB_window").css(style);
}

function TB_getPageScrollTop(){
	var yScrolltop;
	var xScrollleft;
	if (self.pageYOffset || self.pageXOffset) {
		yScrolltop = self.pageYOffset;
		xScrollleft = self.pageXOffset;
	} else if (document.documentElement && document.documentElement.scrollTop || document.documentElement.scrollLeft ){	 // Explorer 6 Strict
		yScrolltop = document.documentElement.scrollTop;
		xScrollleft = document.documentElement.scrollLeft;
	} else if (document.body) {// all other Explorers
		yScrolltop = document.body.scrollTop;
		xScrollleft = document.body.scrollLeft;
	}
	arrayPageScroll = new Array(xScrollleft,yScrolltop) 
	return arrayPageScroll;
}

function TB_getPageSize(){
	var de = document.documentElement;
	var w = window.innerWidth || self.innerWidth || (de&&de.clientWidth) || document.body.clientWidth;
	var h = window.innerHeight || self.innerHeight || (de&&de.clientHeight) || document.body.clientHeight
	arrayPageSize = new Array(w,h) 
	return arrayPageSize;
}

window.addToOnresize(Overlay.calculateDivSize);
window.addToOnresize(Overlay.calculateWindowPosition);