var	image_number = 0;
var image = new Array();

function slideshow_response(req, i)
{
	if(req.readyState == 4) {
		if(req.status == 200) {
			if(req.responseXML) {
				aItems = req.responseXML.getElementsByTagName('item');
			}
			else {
				dom = new ActiveXObject("MSXML.DOMDocument");
				dom.loadXML(req.responseText);
				aItems = dom.documentElement.getElementsByTagName('item');
			}	
	
			for(var i = 0; i < aItems.length; i++) {
				image[i] = new Array();
				image[i].file	= aItems[i].getElementsByTagName('file')[0].firstChild.nodeValue;
				image[i].name	= aItems[i].getElementsByTagName('name')[0].firstChild.nodeValue;
				image[i].credit	= aItems[i].getElementsByTagName('credit')[0].firstChild.nodeValue;
				image[i].link	= aItems[i].getElementsByTagName('link')[0].firstChild.nodeValue;
			}
			
			random_image();
			change_image(1);
		}
	}
}

function start_slideshow()
{
	ajaxRequest('images/images.xml', slideshow_response, 9);
}

function random_image()
{
	var current_date = new Date();
	var ran = 60 / image.length;
	image_number = current_date.getSeconds();
	image_number = Math.floor(image_number / ran);
}

function change_image(fade)
{
	var el = document.getElementById('title_picture');
	var html_str = "<div id='piccy'><img src='' id='pic' alt='' title='' style='border: none; height: 400px; left: 0px; position: absolute; top: 1px; width: 700px; z-index: 1;' class='reflect rheight60' onload='addReflections()' /></div>";
	if(image[image_number].link != '') html_str = '<a href="' + image[image_number].link + '">' + html_str + '</a>';
	el.innerHTML = html_str;

	el = document.getElementById('pic');
	el.setAttribute('src', 'images/' + image[image_number].file);
	el.setAttribute('alt', image[image_number].name);
	el.setAttribute('title', image[image_number].name + "\nCredit: " + image[image_number].credit);

	change_opacity(100, 'title_picture');

	if(fade) setTimeout("fade_out(1)", 8000);
}

function fade_out()
{
	var speed = 2;
	var timer = 0;

	for(i = 100; i >= 0; i--) {
		setTimeout("change_opacity(" + i + ", 'piccy')", timer * speed);
		timer++;
	}
	setTimeout("click_next(1)", 750);
}

function change_opacity(opacity, id)
{
	var object = document.getElementById(id).style;
	object.opacity = (opacity / 100);
	object.MozOpacity = (opacity / 100);
	object.KhtmlOpacity = (opacity / 100);
	object.filter = "alpha(opacity=" + opacity + ")";
}

function click_prev(fade)
{
	image_number--;
	image_number = image_number < 0 ? image.length - 1 : image_number;
	change_image(fade);
}

function click_next(fade)
{
	image_number++;
	image_number = image_number > image.length - 1 ? 0 : image_number;
	change_image(fade);
}