/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2005 Robert Osfield 
 *
 * This library is open source and may be redistributed and/or modified under  
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSG_NODETRACKERCALLBACK
#define OSG_NODETRACKERCALLBACK 1

#include <osg/Node>
#include <osg/NodeCallback>
#include <osg/RefNodePath>

namespace osg
{

class OSG_EXPORT NodeTrackerCallback : public NodeCallback
{
    public:


        void setTrackNodePath(const osg::RefNodePath& nodePath) { _trackNodePath = nodePath; }
        void setTrackNodePath(const osg::NodePath& nodePath) { _trackNodePath = nodePath; }

        osg::RefNodePath& getTrackNodePath() { return _trackNodePath; }
        const osg::RefNodePath& getTrackNodePath() const { return _trackNodePath; }

        void setTrackNode(osg::Node* node);
        osg::Node* getTrackNode() { return _trackNodePath.empty() ? 0 : _trackNodePath.back().get(); }
        const osg::Node* getTrackNode() const { return _trackNodePath.empty() ? 0 : _trackNodePath.back().get(); }


        /** Implements the callback. */
        virtual void operator()(Node* node, NodeVisitor* nv);

        /** Update the node to track the nodepath.*/
        void update(osg::Node& node);

        /** Validate the NodePath by removing any unref'd nodes.*/
        bool validateNodePath() const;

    protected:

        osg::RefNodePath        _trackNodePath;

};

}

#endif