/* -*-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 OSGVIEWER_VIEWEREVENTHANDLERS
#define OSGVIEWER_VIEWEREVENTHANDLERS 1

#include <osg/AnimationPath>
#include <osgText/Text>
#include <osgGA/GUIEventHandler>
#include <osgGA/AnimationPathManipulator>

#include <osgViewer/GraphicsWindow>
#include <osgViewer/Viewer>

namespace osgViewer {

/** Event handler for adding on screen help to Viewers.*/
class OSGVIEWER_EXPORT HelpHandler : public osgGA::GUIEventHandler 
{
    public: 

        HelpHandler(osg::ApplicationUsage* au=0);
        
        void setApplicationUsage(osg::ApplicationUsage* au) { _applicationUsage = au; }
        osg::ApplicationUsage* getApplicationUsage() { return _applicationUsage.get(); }
        const osg::ApplicationUsage* getApplicationUsage() const { return _applicationUsage.get(); }

        void setKeyEventTogglesOnScreenHelp(int key) { _keyEventTogglesOnScreenHelp = key; }
        int getKeyEventTogglesOnScreenHelp() const { return _keyEventTogglesOnScreenHelp; }
        
        void reset();

        osg::Camera* getCamera() { return _camera.get(); }
        const osg::Camera* getCamera() const { return _camera.get(); }

        bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa);

        /** Get the keyboard and mouse usage of this manipulator.*/
        virtual void getUsage(osg::ApplicationUsage& usage) const;

    protected:

        void setUpHUDCamera(osgViewer::ViewerBase* viewer);

        void setUpScene(osgViewer::ViewerBase* viewer);
        
        osg::ref_ptr<osg::ApplicationUsage> _applicationUsage;

        int                                 _keyEventTogglesOnScreenHelp;

        bool                                _helpEnabled;

        bool                                _initialized;
        osg::ref_ptr<osg::Camera>           _camera;
        osg::ref_ptr<osg::Switch>           _switch;
        
};

/** Event handler for adding on screen stats reporting to Viewers.*/
class OSGVIEWER_EXPORT StatsHandler : public osgGA::GUIEventHandler 
{
    public: 

        StatsHandler();

        enum StatsType
        {
            NO_STATS = 0,
            FRAME_RATE = 1,
            VIEWER_STATS = 2,
            LAST = 3
        };
        
        void setKeyEventTogglesOnScreenStats(int key) { _keyEventTogglesOnScreenStats = key; }
        int getKeyEventTogglesOnScreenStats() const { return _keyEventTogglesOnScreenStats; }
        
        void setKeyEventPrintsOutStats(int key) { _keyEventPrintsOutStats = key; }
        int getKeyEventPrintsOutStats() const { return _keyEventPrintsOutStats; }

        double getBlockMultiplier() const { return _blockMultiplier; }

        void reset();

        osg::Camera* getCamera() { return _camera.get(); }
        const osg::Camera* getCamera() const { return _camera.get(); }

        virtual bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa);

        /** Get the keyboard and mouse usage of this manipulator.*/
        virtual void getUsage(osg::ApplicationUsage& usage) const;

    protected:

        void setUpHUDCamera(osgViewer::ViewerBase* viewer);

        osg::Geometry* createGeometry(const osg::Vec3& pos, float height, const osg::Vec4& colour, unsigned int numBlocks);

        osg::Geometry* createFrameMarkers(const osg::Vec3& pos, float height, const osg::Vec4& colour, unsigned int numBlocks);

        osg::Geometry* createTick(const osg::Vec3& pos, float height, const osg::Vec4& colour, unsigned int numTicks);

        osg::Node* createCameraStats(const std::string& font, osg::Vec3& pos, float startBlocks, bool aquireGPUStats, float characterSize, osg::Stats* viewerStats, osg::Camera* camera);

        void setUpScene(osgViewer::ViewerBase* viewer);
        
        void updateThreadingModelText();

        int                                 _keyEventTogglesOnScreenStats;
        int                                 _keyEventPrintsOutStats;

        int                                 _statsType;

        bool                                _initialized;
        osg::ref_ptr<osg::Camera>           _camera;
        
        osg::ref_ptr<osg::Switch>           _switch;
        
        ViewerBase::ThreadingModel          _threadingModel;
        osg::ref_ptr<osgText::Text>         _threadingModelText;

        unsigned int                        _frameRateChildNum;
        unsigned int                        _viewerChildNum;
        unsigned int                        _sceneChildNum;
        unsigned int                        _numBlocks;
        double                              _blockMultiplier;
    
};

/** Event handler allowing to change the screen resolution (in windowed mode) and toggle between fullscreen and windowed mode. */
class OSGVIEWER_EXPORT WindowSizeHandler : public osgGA::GUIEventHandler 
{
public: 

        WindowSizeHandler();

        /** Get the keyboard and mouse usage of this manipulator.*/
        virtual void getUsage(osg::ApplicationUsage &usage) const;

        void setKeyEventToggleFullscreen(int key) { _keyEventToggleFullscreen = key; }
        int getKeyEventToggleFullscreen() const { return _keyEventToggleFullscreen; }

        void setToggleFullscreen(bool flag) { _toggleFullscreen = flag; }
        bool getToggleFullscreen() const { return _toggleFullscreen; }

        void setKeyEventWindowedResolutionUp(int key) { _keyEventWindowedResolutionUp = key; }
        int getKeyEventWindowedResolutionUp() const { return _keyEventWindowedResolutionUp; }
        void setKeyEventWindowedResolutionDown(int key) { _keyEventWindowedResolutionDown = key; }
        int getKeyEventWindowedResolutionDown() const { return _keyEventWindowedResolutionUp; }

        void setChangeWindowedResolution(bool flag) { _changeWindowedResolution = flag; }
        bool getChangeWindowedResolution() const { return _changeWindowedResolution; }

        virtual bool handle(const osgGA::GUIEventAdapter &ea, osgGA::GUIActionAdapter &aa);

protected:

        void toggleFullscreen(osgViewer::GraphicsWindow *window);
        void changeWindowedResolution(osgViewer::GraphicsWindow *window, bool increase);

        unsigned int getNearestResolution(int screenWidth, int screenHeight, int width, int height) const;

        int                     _keyEventToggleFullscreen;
        bool                    _toggleFullscreen;

        int                     _keyEventWindowedResolutionUp;
        int                     _keyEventWindowedResolutionDown;
        bool                    _changeWindowedResolution;
        std::vector<osg::Vec2>  _resolutionList;
        int                     _currentResolutionIndex;
};

/** Event handler allowing to change the viewer threading model */
class OSGVIEWER_EXPORT ThreadingHandler : public osgGA::GUIEventHandler 
{
public: 

        ThreadingHandler();

        /** Get the keyboard and mouse usage of this manipulator.*/
        virtual void getUsage(osg::ApplicationUsage &usage) const;

        void setKeyEventChangeThreadingModel(int key) { _keyEventChangeThreadingModel = key; }
        int getKeyEventChangeThreadingModel() const { return _keyEventChangeThreadingModel; }

        void setChangeThreadingModel(bool flag) { _changeThreadingModel = flag; }
        bool getChangeThreadingModel() const { return _changeThreadingModel; }

        void setKeyEventChangeEndBarrierPosition(int key) { _keyEventChangeEndBarrierPosition = key; }
        int getKeyEventChangeEndBarrierPosition() const { return _keyEventChangeEndBarrierPosition; }

        void setChangeEndBarrierPosition(bool flag) { _changeEndBarrierPosition = flag; }
        bool getChangeEndBarrierPosition() const { return _changeEndBarrierPosition; }

        bool handle(const osgGA::GUIEventAdapter &ea, osgGA::GUIActionAdapter &aa);

protected:

        int             _keyEventChangeThreadingModel;
        bool            _changeThreadingModel;

        int             _keyEventChangeEndBarrierPosition;
        bool            _changeEndBarrierPosition;

        osg::Timer_t    _tickOrLastKeyPress;
        bool            _done;
};

/**
Event handler allowing the user to record the animation "path" of a camera. In it's current
implementation, this handler cannot guarantee the final view matrix is correct; it is
conceivable that the matrix may be one frame off. Eh--not a big deal! :)
TODO: Write the file as we go, not when it's all done.
TODO: Create an osgviewer on-screen indication that animation is taking place.
*/
class OSGVIEWER_EXPORT RecordCameraPathHandler : public osgGA::GUIEventHandler
{
public:

        RecordCameraPathHandler(const std::string &filename = "saved_animation.path");

        void setKeyEventToggleRecord(int key) { _keyEventToggleRecord = key; }
        int getKeyEventToggleRecord() const { return _keyEventToggleRecord; }

        void setKeyEventTogglePlayback(int key) { _keyEventTogglePlayback = key; }
        int getKeyEventTogglePlayback() const { return _keyEventTogglePlayback; }

        virtual void getUsage(osg::ApplicationUsage &usage) const;

        bool handle(const osgGA::GUIEventAdapter &ea, osgGA::GUIActionAdapter &aa);

protected:

        std::string                                     _filename;

        int                                             _keyEventToggleRecord;
        int                                             _keyEventTogglePlayback;


        bool                                            _currentlyRecording;
        bool                                            _currentlyPlaying;
        double                                          _interval;
        double                                          _delta;
        osg::Timer_t                                    _animStartTime;
        osg::Timer_t                                    _lastFrameTime;
        osg::ref_ptr<osg::AnimationPath>                _animPath;
        osg::ref_ptr<osgGA::AnimationPathManipulator>   _animPathManipulator;
        osg::ref_ptr<osgGA::MatrixManipulator>          _oldManipulator;
};

}

#endif