// globals
var g_current;
var g_active_items = new Array();


function get_node(id) {
	 return document.getElementById(id);
}

function display_onclick(id) {
 	 var node = get_node(id);
	 if (!node)
	    return;

	 var id_name = node.getAttribute("id");

	 if (g_current) {
	    var prev_name = g_current.getAttribute("id");
	    if (prev_name == id_name) {
               var removed = false;
               for (var i = 0; i < g_active_items.length; ++i)
		   if (g_active_items[i] == id_name) {
		      g_active_items.splice(i, 1);
		      removed = true;
		      break;
		   }
               if (!removed)
                  g_active_items.push(id_name);
             }
         }
}

function display_onmouseover(id) {
	 var node = get_node(id);
	 if (!node)
	    return;

	 if (g_current) {
	    var keep_active = false;
	    var prev_name = g_current.getAttribute("id");
	 
	    for (var i = 0; i < g_active_items.length; ++i)
	        if (g_active_items[i] == prev_name) {
		   keep_active = true;
		   break;
	        }

	    if (!keep_active)
	       g_current.style.display = 'none';
	 }

	 g_current = node;

	 var id_name = node.getAttribute("id");
	 for (var i = 0; i < g_active_items.length; ++i)
	     if (g_active_items[i] == id_name)
		return;

	 if (node.style.display == 'none') {
	    node.style.display = '';
	 } else {
	    node.style.display = 'none';
	 }
}