var docroot = "";
var resObjekt;

resObjekt = createXMLHttpRequest();

//Portable Funktion zum Erzeugen eines XMLHttpRequest-Objekts
function createXMLHttpRequest() {
  var req = null;
  try {
    req = new ActiveXObject("MSXML2.XMLHTTP");
  }
  catch (err_MSXML2) {
    try {
      req = new ActiveXObject("Microsoft.XMLHTTP");
    }
    catch (err_Microsoft) {
      if (typeof XMLHttpRequest != "undefined") 
        req = new XMLHttpRequest;
    }
  }
  return req;
}

function handleResponse(){
	if(resObjekt.readyState == 4){
		if(resObjekt.responseText == "refresh") location.replace('./');
		else document.getElementById("kopfpic").innerHTML = resObjekt.responseText;
	}
}

function loadKopfpicbg(bildpfad){
	var bildpfad = docroot + bildpfad;
	document.getElementById("kopfpicbg").style.backgroundImage = "url(" + bildpfad + ")";
	setTimeout("switchKopfpic()", 2000);
}

function switchKopfpicbg(zufall){
	var bildpfad = docroot + "bilder/layout/kopfpic/" + zufall + ".jpg";
	document.getElementById("kopfpicbg").style.backgroundImage = "url(" + bildpfad + ")";
}

function switchKopfpic(){
	document.getElementById("kopfpic").style.display = "none";
	var bildpfad = docroot + "bilder/layout/kopfpic/";
	var zufall =  Math.round(Math.random()*11+1);
	resObjekt.open('get', docroot + 'include/switchkopfpic.php?do=switch&bild='+bildpfad+zufall,true);
	resObjekt.onreadystatechange = handleResponse;
	resObjekt.send(null);
	setTimeout("appearKopfpic(" + zufall + ")", 2000);
}

function appearKopfpic(zufall){
	//Überprüfen ob Ajax-Objekt fertig geladen ist.
	if(!(resObjekt.readyState == "4")) setTimeout("appearKopfpic()", 0);
	else{
		new Effect.Appear(document.getElementById("kopfpic"), 2000);
		setTimeout("switchKopfpicbg(" + zufall + ")", 2000);
		setTimeout("switchKopfpic()", 2000);
	}
}

function setFontSize(size){
	document.getElementById("content").style.fontSize = size + "em";
	document.getElementById("box_right").style.fontSize = size + "em";
	document.getElementById("footer").style.fontSize = size + "em";
	document.getElementById("navi").style.fontSize = size + "em";
	document.getElementById("quote").style.fontSize = size + "em";
	if(document.getElementsByTagName("table")[0]) document.getElementsByTagName("table")[0].style.fontSize = size + "em";
	document.getElementsByTagName("h2")[0].style.fontSize = size + 0.4 + "em";
	document.getElementsByTagName("h3")[0].style.fontSize = size + 0.4 + "em";
}

function showMeldung(msg){
  var dim = document.getElementById('dim_bg');
  var meldung = document.getElementById('meldung');
  var meldungtext = document.getElementById('meldungtext');
  dim.style.height = document.body.scrollHeight;
  dim.style.display = "block";
  meldung.style.top = ((screen.availHeight-190)/2)+document.body.scrollTop;
  meldungtext.innerHTML = msg;
  meldung.style.display = "block";
}