var isDragging = false;
var objectToDrag;
var obj;
var ecartX;
var ecartY;
var curX;
var curY;

function positionne(p_id, p_posX, p_pos_Y){
	document.getElementById(p_id).style.left = p_posX;
	document.getElementById(p_id).style.top = p_pos_Y;
}

function getPositionCurseur(e){
	//ie
	if(document.all){
		curX = event.clientX;
		curY = event.clientY;
	}
	
	//netscape 4
	if(document.layers){
		curX = e.pageX;
		curY = e.pageY;
	}
	
	//mozilla
	if(document.getElementById){
		curX = e.clientX;
		curY = e.clientY;
	}
}

function beginDrag(p_obj,e){
	isDragging = true;
	objectToDrag = p_obj;
	getPositionCurseur(e);
	ecartX = curX - parseInt(objectToDrag.style.left);
	ecartY = curY - parseInt(objectToDrag.style.top);
}

function drag(e){
	var newPosX;
	var newPosY;
	if(isDragging == true){
		
		getPositionCurseur(e);
		newPosX = curX - ecartX;
		newPosY = curY - ecartY;

		objectToDrag.style.left = newPosX + 'px';
		objectToDrag.style.top = newPosY + 'px';
		
	}
	
}

function SetCookie (name, value){
	//creation du cookie de nom name et de valeur saisie en paramètre
	document.cookie = name +"=" + value + ";" ;
}

function getCookieVal(offset) {
	var endstr=document.cookie.indexOf (";", offset);
	if (endstr==-1) endstr=document.cookie.length;
	return unescape(document.cookie.substring(offset, endstr));
}

function LireCookie(nom){
	var arg=nom+"=";
	var alen=arg.length;
	var clen=document.cookie.length;
	var i=0;
	while (i<clen){
		var j=i+alen;
		if (document.cookie.substring(i, j)==arg) return getCookieVal(j);
		i=document.cookie.indexOf(" ",i)+1;
		if (i==0) break;
	
	}
	return null;
}



function endDrag(){
	var xpos = objectToDrag.style.left;
	var ypos = objectToDrag.style.top;
	
	isDragging = false;
	
	SetCookie ("xpos", xpos);
	SetCookie ("ypos", ypos);
	
}