var galleryLength = 0;
var current = 0;
var galleryNav = 'galleryNav';
var btnDir = '/i/buttons/';
var dotSrcOff = 'feature_dot.gif';
var dotSrcOn = 'feature_dot_on.gif';
var arrowLeft = 'feature_arrow_l.gif';
var arrowRight = 'feature_arrow_r.gif';

function createGalleryNav(galleryName) {
	if(!document.createElement) return;
	
	var gall = document.getElementById(galleryName);
	
	var navDiv = document.createElement("DIV");
	navDiv.className = "gallery-nav";
	navDiv.setAttribute("id", galleryNav);
	
	var prevLnk = document.createElement("A");
	prevLnk.setAttribute("href","javascript:rotateGalleryUpdate(-1);");
	var prevImg = document.createElement("IMG");
	prevImg.setAttribute("src", btnDir+arrowLeft);
	prevImg.setAttribute("alt", "Previous");
	prevImg.className = "callover";
	prevLnk.appendChild(prevImg);
	
	navDiv.appendChild(prevLnk);
	
	for(var i=0;i<galleryLength;i++) {
		var theDot = document.createElement("IMG");
		if(i==0) {
			theDot.setAttribute("src", btnDir+dotSrcOn);
		}
		else {
			theDot.setAttribute("src", btnDir+dotSrcOff);
		}
		theDot.setAttribute("alt", "Item "+(i+1));
		theDot.setAttribute("name", "c"+i);
		
		navDiv.appendChild(theDot);
	}
	
	var nextLnk = document.createElement("A");
	nextLnk.setAttribute("href","javascript:rotateGalleryUpdate(1);");
	var nextImg = document.createElement("IMG");
	nextImg.setAttribute("src", btnDir+arrowRight);
	nextImg.setAttribute("alt", "Previous");
	nextImg.className = "callover";
	nextLnk.appendChild(nextImg);
	
	navDiv.appendChild(nextLnk);
	
	gall.appendChild(navDiv);
}


function rotateGalleryUpdate(offset) {
	var index = current + offset;
	var old_current = current;
	if (index != current) {
		if (index < galleryLength) {
			if (index < 0) {
				current = galleryLength - 1;
			} else {
				current = index;
			}
		} else {
			current = 0;
		}
		// rotate Billboard
		switchDivs(old_current, current);
		switchCircles(current);
	}
} 

function switchDivs(oldnum, newnum) {
	old_id = "gallery" + oldnum;
	new_id = "gallery" + newnum;
	if (document.getElementById){
		var old_obj = document.getElementById(old_id);
		var new_obj = document.getElementById(new_id);
		if (old_obj.style.display == "none"){
			old_obj.style.display = "";
		} else {
			old_obj.style.display = "none";
		}
		new_obj.style.display = "block";
	}
}

function switchCircles(current) {
	var controls = document.getElementById(galleryNav); /* get Nav container */
	var navImgs = controls.getElementsByTagName("IMG"); /* get all images in container */
	for(var i=0;i<navImgs.length;i++) {
		var imgName = navImgs[i].getAttribute("name");
		if (imgName) {
			if( imgName == 'c'+current ) {
				navImgs[i].setAttribute("src", btnDir+dotSrcOn);
			}
			else {
				navImgs[i].setAttribute("src", btnDir+dotSrcOff);
			}
		}
	}
}

function startGallery() {
	initRollovers("callover");
}

YAHOO.util.Event.addListener(window, "load", startGallery);