// Script to show/hide elements on the Interactive Lists page
//
// Created: 20040806
// Author: Dominic Holmes

var lastParent;
var lastNodes = new Array;	

function expand(node)
{
	var newNodes = new Array;
	
	if (getNextSubItem(node)) {
		currentParent = node;
		
		if (currentParent == lastParent && currentParent.getAttribute('selected') == 'true') {
			while (node = getNextSubItem(node)) {
				node.style.display = 'none';
			}
			lastNodes = null;
			currentParent.setAttribute('selected', 'false');
			currentParent.id = '';
		} else {
			while (node = getNextSubItem(node)) {		
				node.style.display = 'block';						
				newNodes.push (node);
			}
			
			currentParent.setAttribute('selected', 'true');
			currentParent.id = 'selected';
		}
		
		if (currentParent != lastParent) {
			if (lastNodes.length > 0) {
				for (var i in lastNodes) {
					lastNodes[i].style.display = 'none';
				}
                lastParent.setAttribute('selected', 'false');
    			lastParent.id = '';
			}
		}
		lastParent = currentParent;
		lastNodes = newNodes;
	}				
	
	return false;
}

// Returns next sibling pf current node if it is a submenu item		
function getNextSubItem(node) {			
	if (newNode = node.nextSibling) {									
		if (newNode.nodeType == '3') { // IE returns nextSibling immediately, Moz and Opera need to be repeated
			if (newNode.nextSibling) {
					newNode = newNode.nextSibling;
			} else {
				return false;
			}
		} 
		if (newNode.id.substring(5, 6) == '2') {					
			return newNode;
		}
	}
	
	return false;
}