var browserName = navigator.appName;
var browserVersion = parseInt(navigator.appVersion);
var isIE = browserName.indexOf("Microsoft Internet Explorer" )==-1?false:true;
var isNN = browserName.indexOf("Netscape")==-1?false:true;
var isOpera = browserName.indexOf("Opera")==-1?false:true;
var isDOM = document.getElementById?true:false;
var isDomNN = document.layers?true:false;
var isDomIE = document.all?true:false;

if ( isNN && browserVersion>=4 ) layerok=true;
if ( isIE && browserVersion>=4 ) layerok=true;
if ( isOpera && browserVersion>=5 ) layerok=true;

var layerOn = new Array();

function lineOver(nr,state) {

   layerName = 'imgline'+nr;

   if (state == 1) {
        color="#888";
	document.getElementById("preview").style.visibility = "visible";
	document.getElementById("preview").style.position = "absolute";
	document.getElementById("preview").style.top = ((nr*52)+660)+"px";
	document.getElementById("preview").style.width = "220px";

	document.getElementById("preview").src = document.getElementById("thumb"+nr).src;
   }
   if (state == 0) {
	if (layerOn[nr] == true) {color="#CCC";}
        else {color="#fff";}
	document.getElementById("preview").style.visibility = "hidden";
   }

	


   if (isDOM)
      document.getElementById(layerName).style.backgroundColor=color;
    else if (isDomIE)
      document.all[layerName].style.backgroundColor=color;
    else if (isDomNN)
      document.layers[layerName].bgcolor=y;

}

function lineClick(nr) {
   layerName = 'imgline'+nr;
   formElement = 'image'+nr;

   if (layerOn[nr] == true) {
      layerOn[nr] = false;
      color = "#fff";
   } else {
      layerOn[nr] = true;
      color = "#CCC";
   }

   if (isDOM)
      document.getElementById(layerName).style.backgroundColor=color;
    else if (isDomIE)
      document.all[layerName].style.backgroundColor=color;
    else if (isDomNN)
      document.layers[layerName].bgcolor=y;

      document.forms["change_cat"].elements[formElement].checked=layerOn[nr];
	

}

function markAll(count) {
	if (document.getElementById('markAll').firstChild.nodeValue=='Alle markieren') 
	{
		for (i=0;i<count;i++) {layerOn[i] = false;lineClick(i);}
		document.getElementById('markAll').firstChild.nodeValue='Nichts markieren';
	}
	else {
		for (i=0;i<count;i++) {layerOn[i] = true;lineClick(i);}
		document.getElementById('markAll').firstChild.nodeValue='Alle markieren';
	}
}

function markGroup(count) {
	for (i=0;i<count;i++) {layerOn[i] = true;lineClick(i);}
	start = Math.round(allGroups[currentGroup]);
	ende = Math.round(allGroups[currentGroup+1]);

	for (var i=start;i<ende;i++) {lineClick(i);}

	if (currentGroup+2>=allGroups.length) {currentGroup=0;}
	else {currentGroup++;}

}

function markInvert(count) {
	for (i=0;i<count;i++) {lineClick(i);}
}