var init = 'sounds/whoson_aktiviert.mp3';
//var init ='sounds/0.mp3';
var on = 'sounds/user_online_2.mp3';


domain = document.domain;
path = window.location.pathname; // /chat/whoson.php
if (path.indexOf("whoson") != -1) {
	var dir = path.replace("/whoson.php","");
	var install = "//" + domain + dir;
} else {
	var install = "//" + domain + "/chat";
}

// zuerst der AJAX Teil:
// http://aleembawany.com/2005/09/01/ajax-instant-tutorial/
function loadurl(dest) {
        try {
                xmlhttp = window.XMLHttpRequest?new XMLHttpRequest():new ActiveXObject("Microsoft.XMLHTTP");
        }
        catch (e) { /* do nothing */ }

        xmlhttp.onreadystatechange = triggered;
        xmlhttp.open("POST", dest);
        xmlhttp.send(null);
}

function triggered() {
         if (xmlhttp.readyState == 4) document.getElementById("output").innerHTML =xmlhttp.responseText;
}


// und jetzt auto-refresh und sounds:
var anw = 0;

function playsound(typ) { // die standardkonforme Lösung für alle Browser
      if (document.getElementById('ton')) {
      	document.getElementById("ton").innerHTML = '<audio src="'+typ+'" autoplay ></audio>';
      }
}

function refresh() {
	// in folgender Zeile evtl. den kompletten Pfad eingeben: 
	loadurl('anwesend.php');

	y=document.getElementById("output").innerHTML;
	x=y.length;

	if (y.indexOf('noscript') != -1) {
		anw = 0;
	} else if (y.indexOf('niemand') != -1) {
		changeFavicon('img/traurig_ico.png');
		document.title = "Leider niemand im Chat";	
		anw = 0;
	} else {
		changeFavicon('img/favicon.ico');
		document.title = " Chatter anwesend";
		if (anw != 1) {
			playsound(on);
		}
		anw = 1;
	}

	update_refresh = setTimeout(refresh, 3000);
}


document.head = document.head || (document.getElementsByTagName('head')[0]);
function changeFavicon(src) {
	src = src+'?='+Math.random(); // so wird das cachen zuverlässig vermieden
	
	var link = document.createElement('link'),
	oldLink = document.getElementById('dynamic-favicon');
	link.id = 'dynamic-favicon';
	link.rel = 'shortcut icon';
	link.href = src;
	if (oldLink) {
		document.head.removeChild(oldLink);
	}
	document.head.appendChild(link);
}

window.onload = function () {
	playsound(init); // playsound initialisieren
	refresh();
}