function showPic(whichpic) {
  if (!document.getElementById("placeholder")) return true;
  var source = whichpic.getAttribute("href");
  var placeholder = document.getElementById("placeholder");
  placeholder.setAttribute("src",source);
  if (!document.getElementById("description")) return false;
  if (whichpic.getAttribute("title")) {
    var text = whichpic.getAttribute("title");
  } else {
    var text = "";
  }
  var description = document.getElementById("description");
  if (description.firstChild.nodeType == 3) {
    description.firstChild.nodeValue = text;
  }
  return false;
}

function preparePlaceholder() {
	if (!document.createElement) return false;
	if (!document.createTextNode) return false;
	if (!document.getElementById) return false;
	if (!document.getElementById("imagegallery")) return false;
	if (!document.getElementById("secondaryContent")) return false;
	if (!document.getElementById("primaryContent")) return false;
	if (!document.getElementById("description")) return false;
	
	var placeholder = document.createElement("img");
	placeholder.setAttribute("id","placeholder");
	
	// change src to first image in list
	placeholder.setAttribute("src","images/placeholder_sml.gif");
	
	placeholder.setAttribute("alt","my image gallery");
	
	var description = document.getElementById("description");

	var secondary = document.getElementById("primaryContent");
	secondary.appendChild(description);
	secondary.appendChild(placeholder);
	
}

function prepareGallery() {
  if (!document.getElementsByTagName) return false;
  if (!document.getElementById) return false;
  if (!document.getElementById("imagegallery")) return false;
  var newPic;
  var gallery = document.getElementById("imagegallery");
  var links = gallery.getElementsByTagName("a");
  for ( var i=0; i < links.length; i++) {
    links[i].onclick = function() {
      return showPic(this);
    }
    newPic = new Image();
    newPic.src = links[i].href;
  }
  
  
  
  var imgs = gallery.getElementsByTagName("img");
  for (var j=0; j<imgs.length; j++) {
    imgs[j].onmouseover = function() { this.style.borderColor="#FF730E"; }
    imgs[j].onmouseout = function() { this.style.borderColor="#7C3807"; }
  }
  
  // replace placeholder image with first large image
  var source = links[0].getAttribute("href");
  var placeholder = document.getElementById("placeholder");
  placeholder.setAttribute("src",source);
  if (!document.getElementById("description")) return false;
  if (links[0].getAttribute("title")) {
    var text = links[0].getAttribute("title");
  } else {
    var text = "";
  }
  var description = document.getElementById("description");
  if (description.firstChild.nodeType == 3) {
    description.firstChild.nodeValue = text;
  }
}

addLoadEvent(preparePlaceholder);
addLoadEvent(prepareGallery);