/* unobtrusive javascript-tabs */
/* (c)2007 arthur van zuylen, www.2parts.nl */

addEvent(window,'load',getRssLinks);

// haal variabelen uit de DOM
var rsslinks = document.getElementById('rss_lijst').getElementsByTagName('a');
var ajax_feedresults = document.getElementById('ajax_feedresults');

/* initialiseer rss-links tbv ajax-script */
function getRssLinks() {
	// check of javascript voldoende wordt ondersteund door de browser 
	if (!document.getElementById) {
		return;
	}
	
	// check of de lijst bestaat
	if (!document.getElementById('rss_lijst') ||
		!document.getElementById('ajax_feedresults')) {
		return;
	}
	
	// maak mouseclick die de ajax-functie showRSS(nummer) aanroept 
	for(var i=0;i<rsslinks.length;i++) { 
		
		rsslinks[i].onclick = function() {
				
			// bepaal op welke link geklikt is
			var feed_id = this.getAttribute('rel');
			var feed_nr = this.getAttribute('name');
					
			// toon bijbehorende RSS via ajax
			showRSS(feed_id,feed_nr);
			//changeList();
			return false;
		}
	}
}

/* ajaxscript voor RSS-feeds */
function showRSS(feed_id,feed_nr) {
	
	if(feed_id != '') {	
		
		show_spinner2();
		
		var req = getHTTPObject();		
		var url = "includes_php/show_feeds.php?feed_id="+feed_id;
		
		req.open('GET', url, true);
		req.setRequestHeader('Content-Type', 'text/xml; charset=utf-8');
		req.setRequestHeader('X-Requested-With','XMLHttpRequest');
		req.setRequestHeader('If-Modified-Since','Wed, 15 Nov 1995 00:00:00 GMT');
		req.onreadystatechange = function() {
			
			if(req.readyState == 4) {
				if(req.status == 200 || req.status == 304) {
					ajax_feedresults.style.display = 'block';
					ajax_feedresults.style.position = 'relative';
					ajax_feedresults.style.zindex = '1000';
					var margin = (feed_nr - 1) * 28;
					ajax_feedresults.style.margin = '-' + (margin) + 'px 0 0 0';
					ajax_feedresults.innerHTML = req.responseText;
				}
			}
		};
		req.send(null);
	}	
}

/* 'apple'-spinner */ 
function show_spinner2() {
	ajax_feedresults.className = 'show';
	ajax_feedresults.innerHTML = '<img src="beeld/spinner.gif" alt="spinner">';
}

function close_feeds() {
	ajax_feedresults.style.display = 'none';
}