//objects inside the RSS2Item object
function RSS2Enclosure(encElement)
{
	if (encElement == null)
	{
		this.url = null;
		this.length = null;
		this.type = null;
	}
	else
	{
		this.url = encElement.getAttribute("url");
		this.length = encElement.getAttribute("length");
		this.type = encElement.getAttribute("type");
	}
}

function RSS2Guid(guidElement)
{
	if (guidElement == null)
	{
		this.isPermaLink = null;
		this.value = null;
	}
	else
	{
		this.isPermaLink = guidElement.getAttribute("isPermaLink");
		this.value = guidElement.childNodes[0].nodeValue;
	}
}

function RSS2Source(souElement)
{
	if (souElement == null)
	{
		this.url = null;
		this.value = null;
	}
	else
	{
		this.url = souElement.getAttribute("url");
		this.value = souElement.childNodes[0].nodeValue;
	}
}

//object containing the RSS 2.0 item
function RSS2Item(itemxml)
{
	//required
	this.title;
	this.link;
	this.description;

	//optional vars
	this.author;
	this.comments;
	this.pubDate;

	//optional objects
	this.category;
	this.enclosure;
	this.guid;
	this.source;

	var properties = new Array("title", "link", "description", "author", "comments", "pubDate");
	var tmpElement = null;
	for (var i=0; i<properties.length; i++)
	{
		tmpElement = itemxml.getElementsByTagName(properties[i])[0];
		if (tmpElement != null)
			eval("this."+properties[i]+"=tmpElement.childNodes[0].nodeValue");
	}

	this.category = new RSS2Category(itemxml.getElementsByTagName("category")[0]);
	this.enclosure = new RSS2Enclosure(itemxml.getElementsByTagName("enclosure")[0]);
	this.guid = new RSS2Guid(itemxml.getElementsByTagName("guid")[0]);
	this.source = new RSS2Source(itemxml.getElementsByTagName("source")[0]);
}

//objects inside the RSS2Channel object
function RSS2Category(catElement)
{
	if (catElement == null)
	{
		this.domain = null;
		this.value = null;
	}
	else
	{
		this.domain = catElement.getAttribute("domain");
		this.value = catElement.childNodes[0].nodeValue;
	}
}

//object containing RSS image tag info
function RSS2Image(imgElement)
{
	if (imgElement == null)
	{
	this.url = null;
	this.link = null;
	this.width = null;
	this.height = null;
	this.description = null;
	}
	else
	{
		imgAttribs = new Array("url","title","link","width","height","description");
		for (var i=0; i<imgAttribs.length; i++)
			if (imgElement.getAttribute(imgAttribs[i]) != null)
				eval("this."+imgAttribs[i]+"=imgElement.getAttribute("+imgAttribs[i]+")");
	}
}

//object containing the parsed RSS 2.0 channel
function RSS2Channel(rssxml)
{
	//required
	this.title;
	this.link;
	this.description;

	//array of RSS2Item objects
	this.items = new Array();

	//optional vars
	this.language;
	this.copyright;
	this.managingEditor;
	this.webMaster;
	this.pubDate;
	this.lastBuildDate;
	this.generator;
	this.docs;
	this.ttl;
	this.rating;

	//optional objects
	this.category;
	this.image;

	var chanElement = rssxml.getElementsByTagName("channel")[0];
	var itemElements = rssxml.getElementsByTagName("item");
	
	for (var i=0; i<itemElements.length; i++)
	{
		Item = new RSS2Item(itemElements[i]);
		this.items.push(Item);
		//chanElement.removeChild(itemElements[i]);
	}
	
	

	var properties = new Array("title", "link", "description", "pubDate");
	var tmpElement = null;
	for (var i=0; i<properties.length; i++)
	{
	
		tmpElement = chanElement.getElementsByTagName(properties[i])[0];
	
		if (tmpElement != null)
			eval("this."+properties[i]+"=tmpElement.childNodes[0].nodeValue");
	}

	//this.category = new RSS2Category(chanElement.getElementsByTagName("category")[0]);
	//this.image = new RSS2Image(chanElement.getElementsByTagName("image")[0]);
}

//PROCESSES


//uses xmlhttpreq to get the raw rss xml
function getRSS2(url)
{
	try
	{
		//call the right constructor for the browser being used
		if (window.ActiveXObject)
			xhr = new ActiveXObject("Microsoft.XMLHTTP");
		else if (window.XMLHttpRequest)
			xhr = new XMLHttpRequest();
		else
			alert("not supported");
		
		//prepare the xmlhttprequest object
		xhr.open("GET", url, true);
		
		xhr.setRequestHeader("Cache-Control", "no-cache");
		xhr.setRequestHeader("Pragma", "no-cache");

		xhr.onreadystatechange = function() {
			if (xhr.readyState == 4)
			{
				if (xhr.status == 200)
				{
				
					if (xhr.responseText != null)
						processRSS(xhr.responseXML);
					else
					{
						alert("Failed to receive RSS file from the server - file not found.");
						return false;
					}
				}
				else
					alert("Error code " + xhr.status + " received: " + xhr.statusText);
			}
			
		}

		
		//send the request
		xhr.send(null);
	}
	catch(e)
	{
		alert(e);
	}
	
}

//processes the received rss xml
function processRSS(rssxml)
{

	var chanElement = rssxml.getElementsByTagName("channel")[0];
	var itemElements = rssxml.getElementsByTagName("item");
	
	//document.write(itemElements.length);
	
	for (var i=0; i<itemElements.length; i++)
	{
		document.write(itemElements[i]);
	}
	
	

//	RSS = new RSS2Channel(rssxml);

//	showRSS(RSS);
}

function showRSS(RSS)
{
	for (var i=0; i<RSS.items.length; i++)
	{
		
		item_html += (RSS.items[i].title == null) ? "" : RSS.items[i].title;
		
		document.write (item_html);
	}
}

//shows the RSS content in the browser
function xshowRSS(RSS)
{
	//default values for html tags used
	var imageTag = "<img id='chan_image'";
	var startItemTag = "<div id='item'>";
	var startTitle = "<div id='item_title'>";
	var startLink = "<div id='item_link'>";
	var startDescription = "<div id='item_description'>";
	var endTag = "</div>";

	//populate channel data
	var properties = new Array("title","link","description","pubDate","copyright");
	for (var i=0; i<properties.length; i++)
	{
		eval("document.getElementById('chan_"+properties[i]+"').innerHTML = ''");
		curProp = eval("RSS."+properties[i]);
		if (curProp != null)
			eval("document.getElementById('chan_"+properties[i]+"').innerHTML = curProp");
	}

	//show the image
	document.getElementById("chan_image_link").innerHTML = "";
	if (RSS.image.src != null)
	{
		document.getElementById("chan_image_link").href = RSS.image.link;
		document.getElementById("chan_image_link").innerHTML = imageTag
			+" alt='"+RSS.image.description
			+"' width='"+RSS.image.width
			+"' height='"+RSS.image.height
			+"' src='"+RSS.image.url
			+"' "+"/>";
	}

	//populate the items
	document.getElementById("chan_items").innerHTML = "";
	for (var i=0; i<RSS.items.length; i++)
	{
		item_html = startItemTag;
		item_html += (RSS.items[i].title == null) ? "" : startTitle + RSS.items[i].title + endTag;
		//item_html += (RSS.items[i].link == null) ? "" : "<a href=#>" + startLink + RSS.items[i].link + endTag + "</a>";
		item_html += (RSS.items[i].description == null) ? "" : startDescription + RSS.items[i].description + endTag;

		// Use read more link as width=200px
		item_html += (RSS.items[i].link == null) ? "" : "<a href="+RSS.items[i].link +">" + startLink + "Read more" + endTag + "</a>";
		
		
		item_html += endTag;
		document.getElementById("chan_items").innerHTML += item_html;
	}

	//we're done
	//document.getElementById("chan").style.visibility = "visible";
	return true;
}

var xhr;