$(document).ready(function() {
	// setup the default state
	var track_height = $(".categories-track").height();
	var default_family_list_item = $("#notebooks-menu ul.families li a.selected").parent("li");
	if(default_family_list_item.length) {
		position_category_menu(default_family_list_item);
	}
	
	// select a different family
	$("#notebooks-menu ul.families li").mouseenter(function() {
		set_family_selection($(this));
	});
	
	// restore default
	$("#notebooks-menu").mouseleave(function() {
		set_family_selection(default_family_list_item);
	});
	
	function set_family_selection(family_list_item)
	{
		add_family_selected_class(family_list_item);
		position_category_menu(family_list_item);
	}
	
	function add_family_selected_class(family_list_item)
	{
		$("#notebooks-menu ul.families li a.selected").removeClass("selected");
		family_list_item.find("a").addClass("selected");
	}
	
	function position_category_menu(family_list_item)
	{
		var selected_index = family_list_item.index();
		var offset = selected_index * track_height;
		
		$("li#notebooks-menu div.categories").css("top", "-" + offset + "px");
	}
});