var div = "";
function envoyerRequete(requete, url) {
	requete.onreadystatechange = AjaxFin;
	requete.open("GET", url, true);
	requete.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
	requete.send(null);
}

function AjaxDebut(url, cible) {
	//var url = "arbre_ajax.php?arb_id="+arb_id;
	var loading = document.getElementById(cible+"_loading");
	loading.style.visibility="visible";
	loading.style.height="70px";
	div = cible;
	envoyerRequete(requete, url);
}

function AjaxFin () {
	if (requete.readyState == 4) {
		if (requete.status == 200) {
			var reponse = requete.responseText;
			var divTmp = document.getElementById(div);
			
			if (reponse.substr(0,7) == "auth_ok") {
				divTmp.innerHTML = reponse.substr(7,reponse.length-7);
			} else {
				divTmp.innerHTML = reponse;
			}
			
			//var loading = document.getElementById(div+"_loading");
			//loading.style.visibility="hidden";
			//loading.style.height="0px";
			
			if (reponse.substr(0,7) == "auth_ok") {
				// Authentification OK, on redirige
				location.href="accueil.php";
			} else if (reponse.substr(0,7) == "root_ok") {
				// Authentification root OK, on redirige
				location.href="accueil_root.php";
			}
			
			requete = creerRequete();
		}
		else {
    	 // alert("Erreur! Statut de la requête = " + requete.status);
		}
    }
}