// JavaScript Document
function changeBackground() {
	
	// random background
	var newBg = getRandomBackground();
	
	// read cookie
	a = document.cookie;
	cookiename = a.substr(0,a.search('='));
	cookiewert = a.substr(a.search('=')+1,a.search(';'));
	if(cookiewert == '')
	{cookiewert = a.substr(a.search('=')+1,a.length);} 

	// continue due different background
	while(cookiewert == newBg){
		newBg = getRandomBackground();
	}	
	
	document.cookie = 'background = ' + newBg + ';'; 
	document.getElementById('boxContent').style.background=' url(' + newBg + ')';
}

function getRandomBackground() {
	var randombgs=["/img/background-01.jpg", "/img/background-02.jpg", "/img/background-03.jpg", "/img/background-04.jpg", "/img/background-05.jpg", "/img/background-06.jpg", "/img/background-07.jpg", "/img/background-08.jpg"];	
	var newBg = randombgs[Math.floor(Math.random()*randombgs.length)];
	return(newBg);
}



// schaltet sichtbare elemente aus und unsichtbare ein, sofern js aktiviert ist
function toggleSidebox(elementID) {

	// var elements = document.getElementsByName("clickbox");
	//alert(elementID);
	//ie fix
	var elements =(getElementsByName_iefix("div", "clickbox"));
	for (var i = 0; i < elements.length; i++) {
		
		if ((elements[i].id) != elementID) {
			elements[i].style.display = "none";
		}		
	}

	var elem = document.getElementById(elementID);
	
	if(elem.style.display == "none") {
		elem.style.display = "block";
	}
	else {
		elem.style.display = "none";
	}


}

function getElementsByName_iefix(tag, name) {
     
     var elem = document.getElementsByTagName(tag);
     var arr = new Array();
     for(i = 0,iarr = 0; i < elem.length; i++) {
          att = elem[i].getAttribute("name");
          if(att == name) {
               arr[iarr] = elem[i];
               iarr++;
          }
     }
     return arr;
}

function toggleThis(elementID) {

	var elem = document.getElementById(elementID);
	
	if(elem.style.display == "none") {
		elem.style.display = "block";
	}
	else {
		elem.style.display = "none";
	}
}