var TreeMenu = {
	divnav: false, ulnav: false,
	cats_menus: false,
	
	init: function() {
		TreeMenu.divnav = document.getElementById('local_nav');
		TreeMenu.ulnav = TreeMenu.divnav.getElementsByTagName('ul')[0];
		
		lis = TreeMenu.ulnav.childNodes;
		TreeMenu.cats_menus = new Array;
		for(var i = 0; i < lis.length; i++) {
			if(lis[i].nodeName.toLowerCase() == 'li') {
				h2 = lis[i].getElementsByTagName('h2')[0];
				
				if(h2) {
					h2.index = TreeMenu.cats_menus.length;
					TreeMenu.cats_menus[TreeMenu.cats_menus.length] = lis[i].getElementsByTagName('ul')[0];
					
					Lib.addEvent(h2, 'click', TreeMenu.handleCatClick);
				}
			}
		}
	},
	
	handleCatClick: function(e) {
		if(!(el = Lib.getTarget(e))) {
			return false;
		}
		
		ul = TreeMenu.cats_menus[el.index];
		if(Lib.matchClass(ul, 'expand')) {
			Lib.removeClass(ul, 'expand');
		}
		
		else {
			Lib.addClass(ul, 'expand');
		}
	}
	
}

Lib.addEvent(window, 'load', TreeMenu.init);