/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 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 OSGGA_SimpleViewer
#define OSGGA_SimpleViewer 1

#include <osgGA/EventQueue>
#include <osgGA/EventVisitor>
#include <osgGA/MatrixManipulator>

#include <osgDB/DatabasePager>

#include <list>

namespace osgGA{

/** SimpleViewer provide a simple interface for setting up rendering of an scene graph, using a single camera view within a single window.*/
class OSGGA_EXPORT SimpleViewer : public osgGA::GUIActionAdapter, public osg::Referenced
{
    public:

        SimpleViewer();
        virtual ~SimpleViewer();

        void setSceneData(osg::Node* node);
        osg::Node* getSceneData();
        const osg::Node* getSceneData() const;

        osg::CameraNode* getCamera();
        const osg::CameraNode* getCamera() const;

        void setCameraManipulator(MatrixManipulator* manipulator);
        MatrixManipulator* getCameraManipulator() { return _cameraManipulator.get(); }
        const MatrixManipulator* getCameraManipulator() const { return _cameraManipulator.get(); }


        typedef std::list< osg::ref_ptr<GUIEventHandler> > EventHandlers;
        
        void addEventHandler(GUIEventHandler* eventHandler);
        EventHandlers& getEventHandlers() { return _eventHandlers; }
        const EventHandlers& getEventHandlers() const { return _eventHandlers; }

        EventQueue* getEventQueue() { return _eventQueue.get(); }
        const EventQueue* getEventQueue() const { return _eventQueue.get(); }

        void setDatabasePager(osgDB::DatabasePager* dp);
        osgDB::DatabasePager* getDatabasePager() { return _databasePager.get(); }
        const osgDB::DatabasePager* getDatabasePager() const { return _databasePager.get(); }


        /** Render a complete new frame.
          * Calls frameAdvance(), frameEventTraversal(), frameUpateTraversal(), frameCullTraversal() and frameDrawTraversal().
          * Note, no internal makeCurrent() is issued before, or swap buffers called after frame(), these operations are the responsibility of the calling code.*/ 
        virtual void frame();

        virtual void frameAdvance();
        virtual void frameEventTraversal();
        virtual void frameUpdateTraversal();
        virtual void frameCullTraversal();
        virtual void frameDrawTraversal();

        /** Clean up all OpenGL objects associated with this viewer scenegraph. Note, must only be called from the graphics context associated with this viewer.*/ 
        virtual void cleanup();

    public:

        // Override from GUIActionAdapter
        virtual void requestRedraw() {}

        // Override from GUIActionAdapter
        virtual void requestContinuousUpdate(bool /*needed*/=true) {}

        // Override from GUIActionAdapter
        virtual void requestWarpPointer(float /*x*/,float /*y*/) {}
        
        osgUtil::SceneView* getSceneView() { return _sceneView.get(); }
        const osgUtil::SceneView* getSceneView() const { return _sceneView.get(); }

        void init();

    protected:
    
    
        bool                                    _firstFrame;
        osg::Timer_t                            _startTick;
        osg::ref_ptr<osg::FrameStamp>           _frameStamp;

        osg::ref_ptr<osgUtil::SceneView>        _sceneView;

        osg::ref_ptr<osgGA::EventQueue>         _eventQueue;

        osg::ref_ptr<osgGA::MatrixManipulator>  _cameraManipulator;
        EventHandlers                           _eventHandlers;

        osg::ref_ptr<osgGA::EventVisitor>       _eventVisitor;
                
        osg::ref_ptr<osgDB::DatabasePager>      _databasePager;
    
};


}

#endif