/*****
Image Cross Fade Redux
Version 1.0
Last revision: 02.15.2006
steve@slayeroffice.com
Please leave this notice intact. 
Rewrite of old code found here: http://slayeroffice.com/code/imageCrossFade/index.html
*****/


window.addEventListener?window.addEventListener("load",so_init,false):window.attachEvent("onload",so_init);

var d=document, imgs = new Array(), zInterval = null, current=0, pause=false;
var slideShowInterval = 1000 * 2;	//  image change interval in milliseconds
var slideShowRunning = true;	// set true when slideshow active
var crossFadeActive = false;	// set true when crossFade is happening
var slideShow = setTimeout(showNextSlide,slideShowInterval); // start slide show used for slide show timer
var crossFade;	// used for crossfade timer
var slideShowButtonOn = 'img/slideshow/slideshow_slideShowonbtn.gif';
var slideShowButtonOff = 'img/slideshow/slideshow_slideShowoffbtn.gif';
var current=0;


function so_init() {
	if(!d.getElementById || !d.createElement)return;
//	css = d.createElement("link");
//	css.setAttribute("href","image_x-fader.css");
//	css.setAttribute("rel","stylesheet");
//	css.setAttribute("type","text/css");
//	d.getElementsByTagName("head")[0].appendChild(css);

	imgs = d.getElementById("imageContainer").getElementsByTagName("img");
	for(i=1;i<imgs.length;i++) imgs[i].xOpacity = 0;
	imgs[0].style.display = "block";
	imgs[0].xOpacity = .99;
	
}

function so_xfadenext() {
	crossFadeActive = true;
	cOpacity = imgs[current].xOpacity;
	nIndex = imgs[current+1]?current+1:0;
	
	nOpacity = imgs[nIndex].xOpacity;
	
	cOpacity-=.05; 
	nOpacity+=.05;
	
	imgs[nIndex].style.display = "block";
	imgs[current].xOpacity = cOpacity;
	imgs[nIndex].xOpacity = nOpacity;
	
	setOpacity(imgs[current]); 
	setOpacity(imgs[nIndex]);
	
	if(cOpacity<=0) {
		crossFadeActive = false;
		imgs[current].style.display = "none";
		current = nIndex;
		if (slideShowRunning) {
			slideShow = setTimeout(so_xfadenext,slideShowInterval);
		}
	} else {
		setTimeout(so_xfadenext,50);
	}
}

function so_xfadeprev() {	
	crossFadeActive = true;
	cOpacity = imgs[current].xOpacity;
	nIndex = imgs[current-1]?current-1:imgs.length-1;
	
	nOpacity = imgs[nIndex].xOpacity;
	
	cOpacity-=.05; 
	nOpacity+=.05;
	
	imgs[nIndex].style.display = "block";
	imgs[current].xOpacity = cOpacity;
	imgs[nIndex].xOpacity = nOpacity;
	
	setOpacity(imgs[current]); 
	setOpacity(imgs[nIndex]);
	
	if(cOpacity<=0) {
		crossFadeActive = false;
		imgs[current].style.display = "none";
		current = nIndex;
	} else {
		setTimeout(so_xfadeprev,50);
	}
}

function setOpacity(obj) {
	if(obj.xOpacity>.99) {
		obj.xOpacity = .99;
		return;
	}
	obj.style.opacity = obj.xOpacity;
	obj.style.MozOpacity = obj.xOpacity;
	obj.style.filter = "alpha(opacity=" + (obj.xOpacity*100) + ")";
}
	
function showNextSlide () {
	so_xfadenext();
}

function nextCentrifuge() {	
	slideShowRunning = false;
	clearTimeout(slideShow);
	document.getElementById("slideshowbtn").src = slideShowButtonOff;
	so_xfadenext();	
}

function prevCentrifuge()	 {
	slideShowRunning = false;
	clearTimeout(slideShow);
	document.getElementById("slideshowbtn").src = slideShowButtonOff;
	so_xfadeprev();	
}

function toggleSlideShow() {	//	switch active status of slide show

	if ( slideShowRunning == true ) {	// deactivate slideShow
		slideShowRunning = false;
		clearTimeout(slideShow);
		document.getElementById("slideshowbtn").src = slideShowButtonOff;
	} else {	// activate slideShow
		slideShowRunning = true;
		showNextSlide ();
		document.getElementById("slideshowbtn").src = slideShowButtonOn;
	}
}