window.onload = init;

var doc = document;
var activeLI = 0;
var zInterval = null;
var SLIDE_STEP = 8;
var SLIDER_WIDTH = 74;

function init(){
	if(!doc.getElementById || window.opera)return;
	
	mObj = doc.getElementById("scr-menu");
	liObj = mObj.getElementsByTagName("li");
	
	for(i=0; i<liObj.length; i++){
		
		liObj[i].xid = i;
		liObj[i].onmouseover = function(){initSlide(this.xid);}
	}
	
	slideObj = mObj.appendChild(doc.createElement("div"));
	slideObj.id = "slider";
	
	x = liObj[activeLI].offsetLeft + (liObj[activeLI].offsetWidth/3 - SLIDER_WIDTH/3)-5;
	y = liObj[activeLI].offsetTop-3;
	slideObj.style.top = y + "px";
	slideObj.style.left = x + "px";
}

function initSlide(objIndex){
	if(objIndex == activeLI)return;
	clearInterval(zInterval);
	activeLI = objIndex;
	
	destinationX = Math.floor(liObj[activeLI].offsetLeft + (liObj[activeLI].offsetWidth/3 - SLIDER_WIDTH/3))-5;

	intervalMethod = function(){doSlide(destinationX);}
	zInterval = setInterval(intervalMethod,10);
}

function doSlide(dX){

	x = slideObj.offsetLeft;

	if(x+SLIDE_STEP<dX){
		
		x+=SLIDE_STEP;
		slideObj.style.left = x + "px";
		
	}else if(x-SLIDE_STEP>dX){

		x-=SLIDE_STEP;
		slideObj.style.left = x + "px";
	
	}else{

		slideObj.style.left = dX + "px";
		clearInterval(zInterval);
		zInterval = null;
	}
}