var photoBuffer = new Array();
 
//Builds a cached array of img elements
function preloadImages()
{ 
	var i;
 
	//Ok?
	if (!document.getElementById) return;
 
	//Get the link container
	var LinkContainer = document.getElementById("photonav");
 
	//Nope?
	if (!LinkContainer) return;
 
	//Get the links
	var PhotoLinks = LinkContainer.getElementsByTagName("a");
 
	//Loop thru creating the buffer
	for (i = 0; i < PhotoLinks.length; i++)
	{  
		photoBuffer[i] = {
			ImgPath : PhotoLinks[i].getAttribute("href"),
			Description : (PhotoLinks[i].getAttribute("title") ? PhotoLinks[i].getAttribute("title") : ""),
			Element : document.createElement("img")
		}
		photoBuffer[i].Element.src = PhotoLinks[i].getAttribute("href");
		photoBuffer[i].Element.setAttribute("id", "placeholder");  
		photoBuffer[i].Element.setAttribute("alt","my image gallery");
	}
}
 
//Creates the container for the images
function preparePlaceholder()
{
	//Ok?
	if (!document.createElement) return false;
	if (!document.createTextNode) return false;
	if (!document.getElementById) return false;
 
	//No container?
	if (!document.getElementById("photonav")) return false;
 
	//Create the containers
	var photo = document.createElement("div");
	photo.setAttribute("id","photo");
	var content = document.getElementById("content");
	var text = document.getElementById("text");
	content.insertBefore(photo,text);
	var gallery = document.getElementById("photonav");
	var links = gallery.getElementsByTagName("a");
	links[0].setAttribute("class","here");
	var description = document.createElement("p");
	description.setAttribute("id","description");
	photo.appendChild(description);
	var descriptionText = document.createTextNode("");
	description.appendChild(descriptionText); 
	var placeholder = document.createElement("img");
	placeholder.setAttribute("id","placeholder");
	placeholder.setAttribute("alt","my image gallery");
	photo.insertBefore(placeholder,description);
 
	//Load the first image
	showPic(0);
}
 
//Set up links
function prepareGallery() {
	if (!document.getElementsByTagName) return false;
	if (!document.getElementById) return false;
	if (!document.getElementById("photonav")) return false;
	var gallery = document.getElementById("photonav");
	var links = gallery.getElementsByTagName("a");
	for (var i=0; i < links.length; i++) {
		links[i].onclick = function() {
			return showPicByLink(this);
		}
	}
}
 
//Shows an image
function showPicByLink(PicLink)
{
	//Loop thru
	for (var i = 0; i < photoBuffer.length; i++)
	{
		if (PicLink.getAttribute("href").toLowerCase() == photoBuffer[i].ImgPath.toLowerCase())  
		return showPic(i);
	}
}
 
//Shows an image
function showPic(whichpic)
{
	//No place holder?
	if (!document.getElementById("placeholder")) return true;
	if (!document.getElementById("description")) return true;
 
	//Set the links 
	var gallery = document.getElementById("photonav");
	var links = gallery.getElementsByTagName("a");
	for (var i=0; i < links.length; i++) {
		links[i].className="";
	}
	links[whichpic].className="here";
 
	//Get the existing img
	var placeholder = document.getElementById("placeholder");
 
	//Replace 
	placeholder.parentNode.replaceChild(photoBuffer[whichpic].Element, placeholder);
	placeholder = null;
 
	//Put in description
	var description = document.getElementById("description");
	if (description.firstChild.nodeType == 3) {
		description.firstChild.nodeValue = photoBuffer[whichpic].Description;
	}
	return false;
}
 
addLoadEvent(preloadImages);
addLoadEvent(preparePlaceholder);
addLoadEvent(prepareGallery);