var mitheirn_nav = {
   init: function() {
      mitheirn_nav.secondary_navs = {};
      
      // Populate secondary_navs.
      var secondary_nav_root = document.getElementById('secondary-navigation').getElementsByTagName('div')[0];
      var secondary_navs = YAHOO.util.Dom.getElementsByClassName('secondary-navigation-list', 'ul', secondary_nav_root)
      mitheirn_nav.num_secondary_navs = secondary_navs.length;
      for(var i=0; i<mitheirn_nav.num_secondary_navs; i++) {
	 mitheirn_nav.secondary_navs[secondary_navs[i].id] = secondary_navs[i];
      };
      // Set up event handlers.
      var primary_items = document.getElementById('navigation-list').getElementsByTagName('li');
      var num_primary_items = primary_items.length;
      for(var i=0; i<num_primary_items; i++) {
	 YAHOO.util.Event.addListener(primary_items[i], 'mouseover', bgirl_nav.mouseOverHandler);
      };
   },

   mouseOverHandler: function(e) {
      for(var secondary_nav in mitheirn_nav.secondary_navs) {
	 YAHOO.util.Dom.setStyle(mitheirn_nav.secondary_navs[secondary_nav], 'display', 'none');
      };
      var new_current_nav_id = 'secondary-nav-' + this.id;
      if(bgirl_nav.secondary_navs[new_current_nav_id]) {
	 var new_current_nav = mitheirn_nav.secondary_navs[new_current_nav_id];
	 YAHOO.util.Dom.setStyle(new_current_nav, 'display', 'block');
      } else {
	 YAHOO.util.Dom.setStyle(mitheirn_nav.secondary_navs['secondary-nav-empty'], 'display', 'block');
      };
      YAHOO.util.Event.addListener(document.getElementById('header-wrapper'), 'mouseover', bgirl_nav.mouseOutHandler);
      YAHOO.util.Event.addListener(document.getElementById('page-wrapper'), 'mouseover', bgirl_nav.mouseOutHandler);
   },
   
   mouseOutHandler: function(e) {
      var body_classes = document.body.className.split(/\s+/);
      var active_nav_id = '';
      for(var i=1; i<body_classes.length; i++) {
	 if(/\w/.test(body_classes[i])) {
	    active_nav_id = 'secondary-nav-' + body_classes[i];
	    break;
	 }
      }
      for(var secondary_nav in mitheirn_nav.secondary_navs) {
	 YAHOO.util.Dom.setStyle(mitheirn_nav.secondary_navs[secondary_nav], 'display', 'none');
      }
      if(mitheirn_nav.secondary_navs[active_nav_id]) {
	 YAHOO.util.Dom.setStyle(mitheirn_nav.secondary_navs[active_nav_id], 'display', 'block');
      } else {
	 YAHOO.util.Dom.setStyle(mitheirn_nav.secondary_navs['secondary-nav-empty'], 'display', 'block');
      }
   }
};

YAHOO.util.Event.addListener(window, 'load', mitheirn_nav.init);