// multiple on load functions function
function addLoadEvent(func) {
	var oldonload = window.onload;
	if(typeof window.onload != 'function') {
		window.onload = func;
	} else {
		window.onload = function() {
			oldonload();
			func();
		}
	}
}
// image swap function - adds onclick events to thumbnails
function prepImages() {
	if(!document.getElementById) return false;
	if(!document.getElementsByTagName) return false;
	if(!document.getElementById("thumbs")) return false;
	var slideshow = document.getElementById("slideshow");
	var thumbs = document.getElementById("thumbs");
	var links = thumbs.getElementsByTagName("a");
	for(i=0; i<links.length; i++) {
		links[i].onclick = function() {
			var href = this.getAttribute("href");
			slideshow.setAttribute("src",href);
			return false;
		}
	}
}
addLoadEvent(prepImages);
// set current page in nav menu w/ blue bg
function currNav() {
	if(!document.getElementById) return false;
	if(!document.getElementsByTagName) return false;
	if(!document.getElementById("nav")) return false;
	var nav = document.getElementById("nav"); // get nav links
	var links = nav.getElementsByTagName("a");
	var content = document.getElementById("content"); // get ids from body
	var content_divs = content.getElementsByTagName("div");
	for (i=0; i<links.length; i++) { // compare link to id name
		var text = links[i].lastChild.nodeValue;
		for (j=0; j<content_divs.length; j++) {
			var id = content_divs[j].getAttribute("id");
			if(id == text.toLowerCase()) { // if link name = div id name highlight button on nav
				var bingo_li = links[i].parentNode;
				links[i].style.cursor = "default";
				bingo_li.style.border = "1px solid #5C9ACB";
				bingo_li.style.background = "#C4DAF3";
			} else continue;
		}
	}
}
addLoadEvent(currNav);
// preload images
function preloadImages() {
	if(!document.getElementById) return false;
	if(!document.getElementsByTagName) return false;
	if(!document.getElementById("photography")) return false;
	var photo = document.getElementById("photography");
	var imgs = photo.getElementsByTagName("img");
	if(imgs<1) return false;
	if(!document.images) return false;
	for (i=0; i<imgs.length; i++) {
		var src = imgs[i].getAttribute("src");
		var load_img = new Image();
		load_img.src = src;
	}
}
addLoadEvent(preloadImages);