if (window.addEventListener)
{ 
	window.addEventListener("load", getNews, false);
}
else if (window.attachEvent)
{ 
	window.attachEvent("onload", getNews);
}

function getNews()
{
	try
	{	
		var rss = "news/news-feed.rss";
		var asyncRequest; // XMLHttpRequest object variable

		asyncRequest = new XMLHttpRequest(); // create request object

		// register event handler
		asyncRequest.onreadystatechange = function() { processResponse(asyncRequest); }; 

		asyncRequest.open( 'GET', rss, true ); // prepare request
		asyncRequest.send( null ); // send request
	}
	catch ( exception )
	{
		alert( 'Request Failed' );
	}
} 

function processResponse(asyncRequest)
{	
	// console.log(asyncRequest.readyState);

	// if request completed successfully and responseXML is non-null
	if ( asyncRequest.readyState == 4 && asyncRequest.status == 200 
		// && asyncRequest.responseXML 
		)
	{			
		var total = 4; // no. news items required
		var count = 0; // items appended
		
		var news_list = document.getElementById( "news_list" );		

		// get newsitem from responseXML
		var newsitems = asyncRequest.responseXML.getElementsByTagName( "item" );		
		
		// news_list.innerHTML = ''; 
		while(news_list.firstChild) 
		{
			news_list.removeChild( news_list.firstChild );
		}

		while (count < total)
		{
			var newsitem = newsitems.item( count ); // get newsitem from newsitems array

			var link = newsitem.getElementsByTagName( "link" ).
			   item( 0 ).firstChild.nodeValue;

			var title = newsitem.getElementsByTagName( "title" ).
			   item( 0 ).firstChild.nodeValue;		
			
			var li = document.createElement("li");
		
			// create anchor element
			var item_link = document.createElement("a");
			item_link.setAttribute("href", link);
			item_link.appendChild(document.createTextNode( title ));	
			
			li.appendChild( item_link );
			news_list.appendChild(li);			

			count++;
		}
			
			// Manually added default items

			li = document.createElement("li");
			item_link = document.createElement("a");
			item_link.setAttribute("href", "http://www.bris.ac.uk/news/");
			item_link.appendChild(document.createTextNode("News from the University"));	
			li.appendChild( item_link );
			news_list.appendChild(li);

			li = document.createElement("li");
			item_link = document.createElement("a");
			item_link.setAttribute("href", "http://www.bris.ac.uk/news/news-browse.html?category=feng");
			item_link.appendChild(document.createTextNode("Engineering news from the University"));	
			li.appendChild( item_link );
			news_list.appendChild(li);

			li = document.createElement("li");
			item_link = document.createElement("a");
			item_link.setAttribute("href", "http://www.bris.ac.uk/news/news-browse.html?year=&month=&category=research");
			item_link.appendChild(document.createTextNode("University Research News"));	
			li.appendChild( item_link );
			news_list.appendChild(li);
	}
}