var currentZIndex = 500;
var dragStarted = false;


var mouseLocX = 0;
var mouseLocY = 0;
var divLocX = 0;
var divLocY = 0;
var currentlyDaggingDiv = "";

function mouseMoved(e){
	if (!e) e = window.event;
	if (dragStarted){
		currentLeft = divLocX + e.clientX - mouseLocX;
		currentTop = divLocY + e.clientY - mouseLocY;
		currentLeft  = currentLeft<0? 0: currentLeft;
		currentTop  = currentTop<0? 0: currentTop;
		currentlyDaggingDiv.style.left = currentLeft + "px";
		currentlyDaggingDiv.style.top  = currentTop + "px";
		return false;
	}
}

function mousePressed(e,divId){
	if (!e) e = window.event;
	currentlyDaggingDiv = document.getElementById(divId);
	if (divId){
 		dragStarted = true;
		currentlyDaggingDiv.style.zIndex = currentZIndex++;
		divLocX = parseInt(currentlyDaggingDiv.style.left+0);
		divLocY = parseInt(currentlyDaggingDiv.style.top+0);
		mouseLocX = e.clientX;
		mouseLocY = e.clientY;
		document.onmousemove = mouseMoved;
		return false;
	}
}

function mouseReleased(){
	dragStarted = false;
	document.onmousemove = null;
}

document.onmouseup = mouseReleased;