// JavaScript Document
// provides random images for public homepage and first level pages
// Version 20101008

function showImg() {
	
	http_request = false;
	
	var url = "http://www.uzh.ch/uzh/authoring/public_images/provide_image.php";
	if (window.XMLHttpRequest) { // Mozilla, Safari,...
		//alert(url);
		http_request = new XMLHttpRequest();
	} else if (window.ActiveXObject) { // IE
		try {
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try {
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) {}
		}
	}
		
	if (!http_request) {
		//alert('Ende :( Kann keine XMLHTTP-Instanz erzeugen');
		return false;
	}
	
	
	
	http_request.onreadystatechange = writeImg;
	http_request.open('POST', url, true);
	http_request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset iso-8859-1');
	http_request.send();
	
	
}

function writeImg() {
	
	if (http_request.readyState == 4) { 
		
		if (http_request.status == 200  && http_request.responseText.indexOf("http://www.uzh.ch") == 0) {
			ourImage = new Image ();
			ourImage.src = http_request.responseText;
		//	alert (http_request.responseText);
			if (document.getElementById("themesimage") ) {
				document.getElementById("themesimage").innerHTML= "<img src='"+ourImage.src+"' />";
			} else if (document.getElementById("entryimage") ) {
				document.getElementById("entryimage").innerHTML= "<img src='"+ourImage.src+"' />";
			}
		} 
	}
}

$(document).ready(
   function(){
      showImg();
   }
);