function fillContextMenu(name, treeName)
{
    if (!name)    return(false);
    var popupNode = document.getElementById(name);
    if (!popupNode)    return(false);
    // remove the menu node (which tosses all of its kids);
    // do this in case any old command nodes are hanging around
	while (popupNode.childNodes.length)
	{
	  popupNode.removeChild(popupNode.childNodes[0]);
	}

    var treeNode = document.getElementById(treeName);
    if (!treeNode)    return(false);
    var db = treeNode.database;
    if (!db)    return(false);
    
    var compositeDB = db.QueryInterface(Components.interfaces.nsIRDFDataSource);
    if (!compositeDB)    return(false);

    var isupports = Components.classes["component://netscape/rdf/rdf-service"].getService();
    if (!isupports)    return(false);
    var rdf = isupports.QueryInterface(Components.interfaces.nsIRDFService);
    if (!rdf)    return(false);

    var target_item = document.popupNode.parentNode.parentNode;
    if (target_item && target_item.nodeName == "treeitem")
    {
	    if (target_item.getAttribute('selected') != 'true') {
	      treeNode.selectItem(target_item);
	    }
    }

    var select_list = treeNode.selectedItems;

    var separatorResource = rdf.GetResource("http://home.netscape.com/NC-rdf#BookmarkSeparator");
    if (!separatorResource)	return(false);

    // perform intersection of commands over selected nodes
    var cmdArray = new Array();
    var selectLength = select_list.length;
    if (selectLength == 0)	selectLength = 1;
    for (var nodeIndex=0; nodeIndex < selectLength; nodeIndex++)
    {
    	var id = null;

	// if nothing is selected, get commands for the "ref" of the tree root
    	if (select_list.length == 0)
    	{
		id = treeNode.getAttribute("ref");
	        if (!id)    break;
    	}
    	else
    	{
	        var node = select_list[nodeIndex];
	        if (!node)    break;
	        id = node.getAttribute("id");
	        if (!id)    break;
	}

        var rdfNode = rdf.GetResource(id);
        if (!rdfNode)    break;
        var cmdEnum = db.GetAllCmds(rdfNode);
        if (!cmdEnum)    break;

        var nextCmdArray = new Array();
        while (cmdEnum.HasMoreElements())
        {
            var cmd = cmdEnum.GetNext();
            if (!cmd)    break;
            if (nodeIndex == 0)
            {
                cmdArray[cmdArray.length] = cmd;
            }
            else
            {
                nextCmdArray[cmdArray.length] = cmd;
            }
        }
        if (nodeIndex > 0)
        {
            // perform command intersection calculation
            for (var cmdIndex = 0; cmdIndex < cmdArray.length; cmdIndex++)
            {
                var    cmdFound = false;
                for (var nextCmdIndex = 0; nextCmdIndex < nextCmdArray.length; nextCmdIndex++)
                {
                    if (nextCmdArray[nextCmdIndex] == cmdArray[cmdIndex])
                    {
                        cmdFound = true;
                        break;
                    }
                }
                if ((cmdFound == false) && (cmdArray[cmdIndex]))
                {
			var cmdResource = cmdArray[cmdIndex].QueryInterface(Components.interfaces.nsIRDFResource);
                	if ((cmdResource) && (cmdResource != separatorResource))
                	{
				cmdArray[cmdIndex] = null;
			}
                }
            }
        }
    }

    // need a resource to ask RDF for each command's name
    var rdfNameResource = rdf.GetResource("http://home.netscape.com/NC-rdf#Name");
    if (!rdfNameResource)        return(false);

    // build up menu items
    if (cmdArray.length < 1)    return(false);

    var lastWasSep = false;

    for (var cmdIndex = 0; cmdIndex < cmdArray.length; cmdIndex++)
    {
        var cmd = cmdArray[cmdIndex];
        if (!cmd)        continue;
        var cmdResource = cmd.QueryInterface(Components.interfaces.nsIRDFResource);
        if (!cmdResource)    break;

	// handle separators
	if (cmdResource == separatorResource)
	{
		if (lastWasSep != true)
		{
			lastWasSep = true;
		        var menuItem = document.createElement("menuseparator");
		        popupNode.appendChild(menuItem);
		}
		continue;
	}

	lastWasSep = false;

        var cmdNameNode = compositeDB.GetTarget(cmdResource, rdfNameResource, true);
        if (!cmdNameNode)    break;
        cmdNameLiteral = cmdNameNode.QueryInterface(Components.interfaces.nsIRDFLiteral);
        if (!cmdNameLiteral)    break;
        cmdName = cmdNameLiteral.Value;
        if (!cmdName)        break;

        var menuItem = document.createElement("menuitem");
        menuItem.setAttribute("value", cmdName);        
        popupNode.appendChild(menuItem);
        // work around bug # 26402 by setting "oncommand" attribute AFTER appending menuitem
        menuItem.setAttribute("oncommand", "return doContextCmd('" + cmdResource.Value + "', '" + treeName + "');");
    }

	// strip off leading/trailing menuseparators
	while (popupNode.childNodes.length > 0)
	{
		if (popupNode.childNodes[0].tagName != "menuseparator")
			break;
		popupNode.removeChild(popupNode.childNodes[0]);
	}
	while (popupNode.childNodes.length > 0)
	{
		if (popupNode.childNodes[popupNode.childNodes.length - 1].tagName != "menuseparator")
			break;
		popupNode.removeChild(popupNode.childNodes[popupNode.childNodes.length - 1]);
	}

    return(true);
}



function doContextCmd(cmdName, treeName)
{
	var treeNode = document.getElementById(treeName);
	if (!treeNode)    return(false);
	var db = treeNode.database;
	if (!db)    return(false);

	var compositeDB = db.QueryInterface(Components.interfaces.nsIRDFDataSource);
	if (!compositeDB)    return(false);

	var isupports = Components.classes["component://netscape/rdf/rdf-service"].getService();
	if (!isupports)    return(false);
	var rdf = isupports.QueryInterface(Components.interfaces.nsIRDFService);
	if (!rdf)    return(false);

	// need a resource for the command
	var cmdResource = rdf.GetResource(cmdName);
	if (!cmdResource)        return(false);
	cmdResource = cmdResource.QueryInterface(Components.interfaces.nsIRDFResource);
	if (!cmdResource)        return(false);

	// set up selection nsISupportsArray
	var selectionInstance = Components.classes["component://netscape/supports-array"].createInstance();
	var selectionArray = selectionInstance.QueryInterface(Components.interfaces.nsISupportsArray);

	// set up arguments nsISupportsArray
	var argumentsInstance = Components.classes["component://netscape/supports-array"].createInstance();
	var argumentsArray = argumentsInstance.QueryInterface(Components.interfaces.nsISupportsArray);

	// get argument (parent)
	var parentArc = rdf.GetResource("http://home.netscape.com/NC-rdf#parent");
	if (!parentArc)        return(false);

	var select_list = treeNode.selectedItems;
	if (select_list.length < 1)
	{
		// if nothing is selected, default to using the "ref" on the root of the tree
		var	uri = treeNode.getAttribute("ref");
		if (!uri || uri=="")    return(false);
		var rdfNode = rdf.GetResource(uri);
		// add node into selection array
		if (rdfNode)
		{
			selectionArray.AppendElement(rdfNode);
		}
	}
	else for (var nodeIndex=0; nodeIndex<select_list.length; nodeIndex++)
	{
		var node = select_list[nodeIndex];
		if (!node)    break;
		var	uri = node.getAttribute("ref");
		if ((uri) || (uri == ""))
		{
			uri = node.getAttribute("id");
		}
		if (!uri)    return(false);

		var rdfNode = rdf.GetResource(uri);
		if (!rdfNode)    break;

		// add node into selection array
		selectionArray.AppendElement(rdfNode);

		// get the parent's URI
		var parentURI="";
		var	theParent = node;
		while (theParent)
		{
			theParent = theParent.parentNode;

			parentURI = theParent.getAttribute("ref");
			if ((!parentURI) || (parentURI == ""))
			{
				parentURI = theParent.getAttribute("id");
			}
			if (parentURI != "")	break;
		}
		if (parentURI == "")    return(false);

		var parentNode = rdf.GetResource(parentURI, true);
		if (!parentNode)	return(false);

		// add parent arc and node into arguments array
		argumentsArray.AppendElement(parentArc);
		argumentsArray.AppendElement(parentNode);
	}

	// do the command
	compositeDB.DoCommand( selectionArray, cmdResource, argumentsArray );
	return(true);
}



/* Note: doSort() does NOT support natural order sorting! */
function doSort(sortColName)
{
	var node = document.getElementById(sortColName);
	// determine column resource to sort on
	var sortResource = node.getAttribute('resource');
	if (!sortResource) return(false);

	var sortDirection="ascending";
	var isSortActive = node.getAttribute('sortActive');
	if (isSortActive == "true")
	{
		var currentDirection = node.getAttribute('sortDirection');
		if (currentDirection == "ascending")
			sortDirection = "descending";
		else	sortDirection = "ascending";
	}

	var isupports = Components.classes["component://netscape/rdf/xul-sort-service"].getService();
	if (!isupports)    return(false);
	var xulSortService = isupports.QueryInterface(Components.interfaces.nsIXULSortService);
	if (!xulSortService)    return(false);
	xulSortService.Sort(node, sortResource, sortDirection);

	return(true);
}



function setInitialSort(node, sortDirection)
{
	// determine column resource to sort on
	var sortResource = node.getAttribute('resource');
	if (!sortResource) return(false);

	try
	{
		var isupports = Components.classes["component://netscape/rdf/xul-sort-service"].getService();
		if (!isupports)    return(false);
		var xulSortService = isupports.QueryInterface(Components.interfaces.nsIXULSortService);
		if (!xulSortService)    return(false);
		xulSortService.Sort(node, sortResource, sortDirection);
	}
	catch(ex)
	{
	}
	return(true);
}