var parentGameElem = null;

function preroll(url, time)
{
	var gameElem = document.getElementById("HNGame");
	var prerollElem = document.getElementById("prerollElem");
	
	if ( (gameElem != null) && (typeof(gameElem) != "undefined") ) 
	{ 
		parentGameElem = gameElem.parentNode;
		
		if( (prerollElem == null) || (typeof(prerollElem) == "undefined") )
		{
			prerollElem = document.createElement("div");
			prerollElem.id = "prerollElem";
			prerollElem.style.position = "absolute";
			prerollElem.style.background = "#FFFFFF";
			prerollElem.style.width = gameElem.width;
			prerollElem.style.height = gameElem.height;
			prerollElem.style.align = "center";
			prerollElem.style.verticalalign = "middle";
			
			parentGameElem.insertBefore(prerollElem, gameElem);
			
			prerollElem.innerHTML = "<div><iframe src=\""+url+"\" frameborder=\"0\" border=\"0\" scrolling=\"no\" width=\"100%\" height=\"100%\"/></div>";
			gameElem.style.visibility = "hidden";
			
			if ( time>0 ) 
				setTimeout("endOfPreroll()", time);
		}
	}
}

function endOfPreroll()
{
	var gameElem = document.getElementById("HNGame");
	parentGameElem = gameElem.parentNode;
	var prerollElem = document.getElementById("prerollElem");
	parentGameElem.removeChild(prerollElem);
	gameElem.style.visibility = "visible";
}