/* general variables */



var galleryId = 'gallery'; /* change this to the ID of the gallery list */

var	gallery; /* this will be the object reference to the list later on */

var galleryImages; /* array that will hold all child elements of the list */

var currentImage; /* keeps track of which image should currently be showing */

var previousImage;

var preInitTimer;

preInit();



/* functions */



function preInit() {

	if ((document.getElementById)&&(gallery=document.getElementById(galleryId))) {

		gallery.style.visibility = "hidden";
		gallery.style.height = '525px';

		if (typeof preInitTimer != 'undefined') clearTimeout(preInitTimer); 

	} else {

		preInitTimer = setTimeout("preInit()",2);

	}

}



function fader(imageNumber,opacity) {

	/* helper function to deal specifically with images and the cross-browser differences in opacity handling */

	var obj=galleryImages[imageNumber];

	if (obj.style) {

		if (obj.style.MozOpacity!=null) {  

			/* Mozilla's pre-CSS3 proprietary rule */

			obj.style.MozOpacity = (opacity/100) - .001;

		} else if (obj.style.opacity!=null) {

			/* CSS3 compatible */

			obj.style.opacity = (opacity/100) - .001;

		} else if (obj.style.filter!=null) {

			/* IE's proprietary filter */

			obj.style.filter = "alpha(opacity="+opacity+")";

		}

	}

}



function fadeInit() {

	if (document.getElementById) {

		preInit(); /* shouldn't be necessary, but IE can sometimes get ahead of itself and trigger fadeInit first */

		galleryImages = new Array;

		var node = gallery.firstChild;

		/* instead of using childNodes (which also gets empty nodes and messes up the script later)

		we do it the old-fashioned way and loop through the first child and its siblings */

		while (node) {

			if (node.nodeType==1) {

				galleryImages.push(node);

			}

			node = node.nextSibling;

		}

		for(i=0;i<galleryImages.length;i++) {

			/* loop through all these child nodes and set up their styles */

			galleryImages[i].style.position='absolute';

			galleryImages[i].style.zIndex=0;

			/* set their opacity to transparent */

			fader(i,0);

		}

		/* make the list visible again */

		gallery.style.visibility = 'visible';

		/* initialise a few parameters to get the cycle going */

		currentImage=0;

		previousImage=galleryImages.length-1;

		opacity=100;

		fader(currentImage,100);

		/* start the whole crossfade process after a second's pause */

		window.setTimeout("crossfade(100)", 1000);

	}

}



function crossfade(opacity) {

		if (opacity < 100) {

			/* current image not faded up fully yet...so increase its opacity */

			fader(currentImage,opacity);

			/* fader(previousImage,100-opacity); */

			opacity += 10;

			window.setTimeout("crossfade("+opacity+")", 30);

		} else {

			/* resize container to match */

			pos_x = galleryImages[currentImage].offsetWidth;

    		pos_y = galleryImages[currentImage].offsetHeight;

			document.getElementById("galleryContainer").style.height = pos_y + 'px';

			document.getElementById("galleryContainer").style.width = pos_x + 'px';

			

			/* make the previous image - which is now covered by the current one fully - transparent */

			fader(previousImage,0);

			/* current image is now previous image, as we advance in the list of images */

			previousImage=currentImage;

			currentImage+=1;

			

			if (currentImage>=galleryImages.length) {

				/* start over from first image if we cycled through all images in the list */

				currentImage=0;

			}

			/* make sure the current image is on top of the previous one */	

			galleryImages[previousImage].style.zIndex = 0;

			galleryImages[currentImage].style.zIndex = 100;

			/* and start the crossfade after a second's pause */

			opacity=0;

			window.setTimeout("crossfade("+opacity+")", 1000);

		}

		

}



/* initialise fader by hiding image object first */

addEvent(window,'load',fadeInit)



/* addEvent handler for IE and other browsers */

function addEvent(elm, evType, fn, useCapture) 

{

 if (elm.addEventListener){

   elm.addEventListener(evType, fn, useCapture);

   return true;

 } else if (elm.attachEvent){

   var r = elm.attachEvent("on"+evType, fn);

   return r;

 }

}