var template = 'wall_2C_NAV';
var imgContract = './templates/' + template + '/images/contract.gif';
var imgExpand = './templates/' + template + '/images/expand.gif';

function init(){

	if(!document.getElementById) return;
	if(!document.getElementsByTagName) return;
	if(!document.createElement) return;

	var navigation = document.getElementById('nav');
	var navSub = navigation.getElementsByTagName('ul');
	var navSubArt = navigation.getElementsByTagName('li');
  var par = 0;

	for (i=0; i<navSubArt.length; i++){
    x = document.getElementsByTagName('li')[i];	
    if(x.className == "artlink") {par = 2;} else {par = 1;}	
  }

	for (i=0; i<par; i++){
  	var toggleImage = document.createElement('img');
  	toggleImage.setAttribute('src', imgContract);
  	toggleImage.style.cursor = "pointer";
  	toggleImage.onclick = function() {
  		toggleNav(this);
  	}
  	navSub[i].parentNode.insertBefore(toggleImage, navSub[i].parentNode.firstChild);
  	navSub[i].style.display="block";
  	navSub[i].parentNode.className = "expandable";
  }

	for (i=par; i<navSub.length; i++){
		var toggleImage = document.createElement('img');
		toggleImage.setAttribute('src', imgExpand);
		toggleImage.style.cursor = "pointer";
		toggleImage.onclick = function() {
			toggleNav(this);
		}
		navSub[i].parentNode.insertBefore(toggleImage, navSub[i].parentNode.firstChild);
		navSub[i].style.display = "none";
		navSub[i].parentNode.className = "expandable";
	}


}

function toggleNav(whichOne){

	var theParent = whichOne.parentNode;
	var theParentULs = theParent.getElementsByTagName('ul');
	var theParentImage = theParent.getElementsByTagName('img');
	
	if (theParentULs[0].style.display == "none") {
		theParentULs[0].style.display = "block";
		theParentImage[0].setAttribute('src', imgContract);
	}
	else {
		theParentULs[0].style.display = "none";
		theParentImage[0].setAttribute('src', imgExpand);
	}
	
}

window.onload = init;