function newRandomPromo(xmluri){
	var promoContent = new XMLHTTP();
	promoContent.open("GET", xmluri, true);
	promoContent.onreadystatechange = function(){
		if (promoContent.readyState == 4) {
			if (promoContent.status == 200) {
				var xmlObj = promoContent.responseXML.documentElement;
				var promoNum = xmlObj.getElementsByTagName('promo').length;	
				//generates random number
				var aryId=Math.floor(Math.random()*promoNum)
				
				//pull promo data
				var contentContainer = xmlObj.getElementsByTagName('contentContainer')[0].childNodes[0].nodeValue;
				var promoTitle = xmlObj.getElementsByTagName('promo')[aryId].getAttribute("id");
				var promoMediaType = xmlObj.getElementsByTagName('promo')[aryId].getElementsByTagName('media')[0].getAttribute("type");
				var promoMediaURL = xmlObj.getElementsByTagName('promo')[aryId].getElementsByTagName('media')[0].childNodes[0].nodeValue;
				try{
					var promoText = xmlObj.getElementsByTagName('promo')[aryId].getElementsByTagName('text')[0].childNodes[0].nodeValue;
				}catch(e){
					var promoText = ' ';
				}										
				var promoLink = xmlObj.getElementsByTagName('promo')[aryId].getElementsByTagName('link')[0].childNodes[0].nodeValue;
				
				//different mime type embed
				if (promoMediaType == 'image') {
					document.getElementById(contentContainer).innerHTML = '<p class="image_small_short">\n<a class="imagelink" href="' + promoLink + '" title="' + promoTitle + '" /><img src="' + promoMediaURL + '" alt="promo" /></a>\n</p>\n' + promoText;
				} else if (promoMediaType == 'flash') {
					document.getElementById(contentContainer).innerHTML = '<p class="image_small_short">\n<object width="210" height="80" wmode="opaque"><param name="movie" value="' + promoMediaURL + '"><embed src="' + promoMediaURL + '" width="210" height="80"></embed></object>\n</p>' + promoText;
				}
			} else {
				// Error loading file!
			}
		}
		promoContent = new XMLHTTP();
 	}
	promoContent.send(null);	
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}

addLoadEvent(function() {
	newRandomPromo('http://www.engineering.unl.edu/sharedcode/Promos/promoRandom.xml');
});