var timeout	= 200;
var closetimer	= 0;
var ddmenuitem	= 0;

function swap(imgObject) {
	var neededImg;
	if(imgObject.src.indexOf("_over") > 0) {
		neededImg = findImage(imgObject.id, menuImages);
		imgObject.src = menuImagesRoot + neededImg;
		//alert('setting img to ' + neededImg);
	} else {
		neededImg = findImage(imgObject.id, menuImagesOver);
		imgObject.src = menuImagesRoot + neededImg;
		//alert('setting img to ' + neededImg);
	}
}

function findImage(imgName, arrayObj) {
	for (i=0; i < arrayObj.length; i++) {
		//alert('checking ' + arrayObj[i] + ' for ' + imgName);
		if(arrayObj[i].indexOf(imgName) != -1) {
			//alert('match!');
			return arrayObj[i];
		}
	}
	return null;
}

// open hidden layer
function mopen(id)
{	
	// cancel close timer
	mcancelclosetime();

	// close old layer
	if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';

	// get new layer and show it
	ddmenuitem = document.getElementById(id);
	ddmenuitem.style.visibility = 'visible';

}
// close shown layer
function mclose()
{
	if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
}

// go close timer
function mclosetime()
{
	closetimer = window.setTimeout(mclose, timeout);
}

// cancel close timer
function mcancelclosetime()
{
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}

// close layer when click-out
document.onclick = mclose;