var prev_index = -1; // No testimonial displayed yet. Random index will be set.

function loadXMLDoc(url){
	var xmlhttp;
	var txt,x,xx;
	if(window.XMLHttpRequest){// code for IE7+, Firefox, Chrome, Opera, Safari
		xmlhttp=new XMLHttpRequest();
	}else{// code for IE6, IE5
		xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
	}
	
	xmlhttp.onreadystatechange=function(){
	
		if(xmlhttp.readyState==4 && xmlhttp.status==200){
			
			
			x=xmlhttp.responseXML.documentElement.getElementsByTagName("testimonial");

			if(prev_index == -1){ // This is the first time to show since the webpage has been loaded
				random_index = Math.floor(Math.random() * (x.length)); // set random between 0 ~ length of xml data.
			}else{
				if(prev_index<x.length-1){ // Don't over the length of array
					random_index = prev_index+1;
				}else{
					random_index = 0; // Instead of "overflowing array index", set zero
				}
			}
			prev_index = random_index; // remember which index was displayed.
			
			txt='';
			txt=txt+'<div class="testimonialImage"><a href="testimonials.php">';
			xx=x[random_index].getElementsByTagName("image");
			if(xx[0]){
				try{
					txt=txt + '<img src="' + xx[0].firstChild.nodeValue + '"';
				}catch(er){
					txt=txt + 'xml format error: image source';
				}
			}
			xx=x[random_index].getElementsByTagName("imagealt");
			if(xx[0]){
				try{
					txt=txt + ' alt="' + xx[0].firstChild.nodeValue + '" />';
				}catch(er){
					txt=txt + 'xml format error: image alt';
				}
			}
			txt=txt+'</a></div>';
			
			txt=txt+'<div class="testimonialContent">';
			xx=x[random_index].getElementsByTagName("testim_title");
			if(xx[0]){
				try{
					txt=txt + '<div class="testimTitle"><a href="testimonials.php" class="cellLink">' + xx[0].firstChild.nodeValue + '</a></div>';
				}catch(er){
					txt=txt + 'xml format error: testimonial title';
				}
			}
			xx=x[random_index].getElementsByTagName("testim_text");
			if(xx[0]){
				try{
					txt=txt + '<div class="testimText">' + xx[0].firstChild.nodeValue + '</div>';
				}catch(er){
					txt=txt + 'xml format error: testimonial text';
				}
			}
			xx=x[random_index].getElementsByTagName("name");
			if(xx[0]){
				try{
					txt=txt + '<div class="testimSign">' + xx[0].firstChild.nodeValue + '</div>';
				}catch(er){
					txt=txt + 'xml format error: name';
				}
			}
			xx=x[random_index].getElementsByTagName("position");
			if(xx[0]){
				try{
					txt=txt + '<div class="testimSign">- ' + xx[0].firstChild.nodeValue + '</div>';
				}catch(er){
					txt=txt + '';
				}
			}
			txt=txt+'</div>';
			
			function nextTestimonial(){
				$("#testimonial #sliding_content").html(txt);
			}
			$("#testimonial #sliding_content").effect('slide', { direction: "left", mode: "hide"},250,nextTestimonial);
			
			$("#testimonial #sliding_content").effect('slide', { direction: "right", mode: "show"},500);
		}
	}
	
	xmlhttp.open("GET",url,true);
	xmlhttp.send();		
	t=setTimeout("loadXMLDoc('testimonial_data.php')", 4000);
}

$(document).ready(function(){
	loadXMLDoc('testimonial_data.php');
});