addLoadEvent(collapseMenu);
addLoadEvent(prepareMenu);

function collapseMenu(node) {
	if (!document.getElementById) return false;
	if (!document.getElementById("menu")) return false;
	if (!node) node = document.getElementById("menu");

	if (node.childNodes.length > 0) {
		for (var i=0; i<node.childNodes.length; i++) {
			var child = node.childNodes[i];
			if (child.nodeName == "UL") {
					child.style.display = "none";
			}
			collapseMenu(child);
		}		
	}

}

function prepareMenu() {
	if (!document.getElementById || !document.getElementsByTagName) return false;
	if (!document.getElementById("menu")) return false;

	var links = document.getElementById("menu").getElementsByTagName("a");
	for (var i=0; i<links.length; i++) {		
		links[i].onclick = function() {
			toggleMenu(this.parentNode.getElementsByTagName("UL")[0], this.href);
			return false;
		}
	}
}

function toggleMenu(node, link) {
	if (!document.getElementById) return false;
	if (!link) return false;
	if (!node) location.href = link.href;

	// Collapse all nodes, and only show clicked node (when clicking top level of menu)
	if (node.parentNode.parentNode.id == "menu") {
		hideTopLevels();
	}
	
	if (node.style.display == "") {
 		node.style.display = "none";
	} else {
 		node.style.display = "";
	}
	
	
}

function hideTopLevels() {
	if (!document.getElementById) return false;
	if (!(node = document.getElementById("menu"))) return false;	
	
	if (node.childNodes.length > 0) {
		for (var i=0; i<node.childNodes.length; i++) {
			var child = node.childNodes[i];
			for(var j=0; j<child.childNodes.length; j++) {
				var grandchild = child.childNodes[j];
				if (grandchild.nodeName == "UL") {
					if (grandchild.style.display == '') {
						Effect.BlindUp(grandchild, {duration: 0.2});
					}
				}
			}
		}		
	}
}