/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield 
 *
 * This application is open source and may be redistributed and/or modified   
 * freely and without restriction, both in commericial and non commericial applications,
 * as long as this copyright notice is maintained.
 * 
 * This application 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.
*/

#include <osgDB/ReadFile>
#include <osgUtil/Optimizer>
#include <osg/CoordinateSystemNode>

#include <osg/Switch>
#include <osgText/Text>

#include <osgViewer/Viewer>
#include <osgViewer/StatsHandler>
#include <osgViewer/HelpHandler>

#include <osgGA/TrackballManipulator>
#include <osgGA/FlightManipulator>
#include <osgGA/DriveManipulator>
#include <osgGA/KeySwitchMatrixManipulator>
#include <osgGA/StateSetManipulator>
#include <osgGA/AnimationPathManipulator>
#include <osgGA/TerrainManipulator>

#include <iostream>

class ThreadingHandler : public osgGA::GUIEventHandler 
{
public: 

    ThreadingHandler()
    {
       _tickOrLastKeyPress = osg::Timer::instance()->tick();
    }

        
    bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa)
    {
        osgViewer::Viewer* viewer = dynamic_cast<osgViewer::Viewer*>(&aa);
        if (!viewer) return false;
    
        switch(ea.getEventType())
        {
            case(osgGA::GUIEventAdapter::KEYUP):
            {

                double delta = osg::Timer::instance()->delta_s(_tickOrLastKeyPress, osg::Timer::instance()->tick());

                if (ea.getKey()=='m' && delta>1.0)
                {

                    _tickOrLastKeyPress = osg::Timer::instance()->tick();

                    switch(viewer->getThreadingModel())
                    {
                        case(osgViewer::Viewer::SingleThreaded):
                            viewer->setThreadingModel(osgViewer::Viewer::CullDrawThreadPerContext);
                            osg::notify(osg::NOTICE)<<"Threading model 'CullDrawThreadPerContext' selected."<<std::endl;
                            break;
                        case(osgViewer::Viewer::CullDrawThreadPerContext):
                            viewer->setThreadingModel(osgViewer::Viewer::DrawThreadPerContext);
                            osg::notify(osg::NOTICE)<<"Threading model 'DrawThreadPerContext' selected."<<std::endl;
                            break;
                        case(osgViewer::Viewer::DrawThreadPerContext):
                            viewer->setThreadingModel(osgViewer::Viewer::CullThreadPerCameraDrawThreadPerContext);
                            osg::notify(osg::NOTICE)<<"Threading model 'CullThreadPerCameraDrawThreadPerContext' selected."<<std::endl;
                            break;
                        case(osgViewer::Viewer::CullThreadPerCameraDrawThreadPerContext):
                            viewer->setThreadingModel(osgViewer::Viewer::SingleThreaded);
                            osg::notify(osg::NOTICE)<<"Threading model 'SingleThreaded' selected."<<std::endl;
                            break;
                        case(osgViewer::Viewer::AutomaticSelection):
                            viewer->setThreadingModel(viewer->suggestBestThreadingModel());
                            osg::notify(osg::NOTICE)<<"Threading model 'AutomaticSelection' selected."<<std::endl;
                            break;
                    }
                    return true;
                }
                if (ea.getKey()=='e')
                {
                    switch(viewer->getEndBarrierPosition())
                    {
                        case(osgViewer::Viewer::BeforeSwapBuffers):
                            viewer->setEndBarrierPosition(osgViewer::Viewer::AfterSwapBuffers);
                            osg::notify(osg::NOTICE)<<"Threading model 'AfterSwapBuffers' selected."<<std::endl;
                            break;
                        case(osgViewer::Viewer::AfterSwapBuffers):
                            viewer->setEndBarrierPosition(osgViewer::Viewer::BeforeSwapBuffers);
                            osg::notify(osg::NOTICE)<<"Threading model 'BeforeSwapBuffers' selected."<<std::endl;
                            break;
                    }
                    return true;
                }
            }
            default: break;
        }
        
        return false;
    }
    
    /** Get the keyboard and mouse usage of this manipulator.*/
    virtual void getUsage(osg::ApplicationUsage& usage) const
    {
        usage.addKeyboardMouseBinding("m","Toggle threading model.");
        usage.addKeyboardMouseBinding("e","Toggle the placement of the end of frame barrier.");
    }

    osg::Timer_t _tickOrLastKeyPress;
    bool _done;
};


class FullScreenToggleHandler : public osgGA::GUIEventHandler 
{
public: 

    FullScreenToggleHandler() {}
        
    bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa)
    {
        osgViewer::Viewer* viewer = dynamic_cast<osgViewer::Viewer*>(&aa);
        if (!viewer) return false;
    
        switch(ea.getEventType())
        {
            case(osgGA::GUIEventAdapter::KEYUP):
            {
                if (ea.getKey()=='f')
                {
                    osgViewer::Viewer::Windows windows;
                    viewer->getWindows(windows);
                    
                    for(osgViewer::Viewer::Windows::iterator itr = windows.begin();
                        itr != windows.end();
                        ++itr)
                    {
                        toggleFullscreen(*itr);
                    }
                }
            }
            default: break;
        }
        
        return false;
    }
    
    /** Get the keyboard and mouse usage of this manipulator.*/
    virtual void getUsage(osg::ApplicationUsage& usage) const
    {
        usage.addKeyboardMouseBinding("f","Toggle full screen.");
    }


    void toggleFullscreen(osgViewer::GraphicsWindow* window)
    {

        osg::GraphicsContext::WindowingSystemInterface* wsi = osg::GraphicsContext::getWindowingSystemInterface();
        if (!wsi) 
        {
            osg::notify(osg::NOTICE)<<"Error, no WindowSystemInterface available, cannot toggle window fullscreen."<<std::endl;
            return;
        }
        
        unsigned int screen_width, screen_height;
        wsi->getScreenResolution(*(window->getTraits()), screen_width, screen_height);
        
        int x, y, width, height;
        window->getWindowRectangle(x, y, width, height);
        
        bool isFullScreen = x==0 && y==0 && width==screen_width && height==screen_height;
        if (isFullScreen)
        {
            window->setWindowRectangle(screen_width/4, screen_height/4, screen_width/2, screen_height/2);
            window->setWindowDecoration(true);
        }
        else
        {
            window->setWindowDecoration(false);
            window->setWindowRectangle(0, 0, screen_width, screen_height);
        }
        
        window->grabFocusIfPointerInWindow();
        
        return;
        
    }
        


    bool _done;
};

int main(int argc, char** argv)
{
    // use an ArgumentParser object to manage the program arguments.
    osg::ArgumentParser arguments(&argc,argv);

    arguments.getApplicationUsage()->setApplicationName(arguments.getApplicationName());
    arguments.getApplicationUsage()->setDescription(arguments.getApplicationName()+" is the standard OpenSceneGraph example which loads and visualises 3d models.");
    arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] filename ...");
    arguments.getApplicationUsage()->addCommandLineOption("--image <filename>","Load an image and render it on a quad");
    arguments.getApplicationUsage()->addCommandLineOption("--dem <filename>","Load an image/DEM and render it on a HeightField");
    arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display command line parameters");
    arguments.getApplicationUsage()->addCommandLineOption("--help-env","Display environmental variables available");
    arguments.getApplicationUsage()->addCommandLineOption("--help-keys","Display keyboard & mouse bindings available");
    arguments.getApplicationUsage()->addCommandLineOption("--help-all","Display all command line, env vars and keyboard & mouse bindings.");
    arguments.getApplicationUsage()->addCommandLineOption("--SingleThreaded","Select SingleThreaded threading model for viewer.");
    arguments.getApplicationUsage()->addCommandLineOption("--CullDrawThreadPerContext","Select CullDrawThreadPerContext threading model for viewer.");
    arguments.getApplicationUsage()->addCommandLineOption("--DrawThreadPerContext","Select DrawThreadPerContext threading model for viewer.");
    arguments.getApplicationUsage()->addCommandLineOption("--CullThreadPerCameraDrawThreadPerContext","Select CullThreadPerCameraDrawThreadPerContext threading model for viewer.");

    // if user request help write it out to cout.
    bool helpAll = arguments.read("--help-all");
    unsigned int helpType = ((helpAll || arguments.read("-h") || arguments.read("--help"))? osg::ApplicationUsage::COMMAND_LINE_OPTION : 0 ) |
                            ((helpAll ||  arguments.read("--help-env"))? osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE : 0 ) |
                            ((helpAll ||  arguments.read("--help-keys"))? osg::ApplicationUsage::KEYBOARD_MOUSE_BINDING : 0 );
    if (helpType)
    {
        arguments.getApplicationUsage()->write(std::cout, helpType);
        return 1;
    }

    // report any errors if they have occurred when parsing the program arguments.
    if (arguments.errors())
    {
        arguments.writeErrorMessages(std::cout);
        return 1;
    }
    
    if (arguments.argc()<=1)
    {
        arguments.getApplicationUsage()->write(std::cout,osg::ApplicationUsage::COMMAND_LINE_OPTION);
        return 1;
    }

    osgViewer::Viewer viewer;
    
    // set up the camera manipulators.
    {
        osg::ref_ptr<osgGA::KeySwitchMatrixManipulator> keyswitchManipulator = new osgGA::KeySwitchMatrixManipulator;

        keyswitchManipulator->addMatrixManipulator( '1', "Trackball", new osgGA::TrackballManipulator() );
        keyswitchManipulator->addMatrixManipulator( '2', "Flight", new osgGA::FlightManipulator() );
        keyswitchManipulator->addMatrixManipulator( '3', "Drive", new osgGA::DriveManipulator() );
        keyswitchManipulator->addMatrixManipulator( '4', "Terrain", new osgGA::TerrainManipulator() );

        std::string pathfile;
        char keyForAnimationPath = '5';
        while (arguments.read("-p",pathfile))
        {
            osgGA::AnimationPathManipulator* apm = new osgGA::AnimationPathManipulator(pathfile);
            if (apm || !apm->valid()) 
            {
                unsigned int num = keyswitchManipulator->getNumMatrixManipulators();
                keyswitchManipulator->addMatrixManipulator( keyForAnimationPath, "Path", apm );
                keyswitchManipulator->selectMatrixManipulator(num);
                ++keyForAnimationPath;
            }
        }

        viewer.setCameraManipulator( keyswitchManipulator.get() );
    }

    // add the state manipulator
    viewer.addEventHandler( new osgGA::StateSetManipulator(viewer.getCamera()->getOrCreateStateSet()) );
    
    // add the thread model handler
    viewer.addEventHandler(new ThreadingHandler);

    // add the full screen toggle handler
    viewer.addEventHandler(new FullScreenToggleHandler);
    
    // add the stats handler
    viewer.addEventHandler(new osgViewer::StatsHandler);

    // add the help handler
    viewer.addEventHandler(new osgViewer::HelpHandler(arguments.getApplicationUsage()));

    while (arguments.read("--SingleThreaded")) viewer.setThreadingModel(osgViewer::Viewer::SingleThreaded);
    while (arguments.read("--CullDrawThreadPerContext")) viewer.setThreadingModel(osgViewer::Viewer::CullDrawThreadPerContext);
    while (arguments.read("--DrawThreadPerContext")) viewer.setThreadingModel(osgViewer::Viewer::DrawThreadPerContext);
    while (arguments.read("--CullThreadPerCameraDrawThreadPerContext")) viewer.setThreadingModel(osgViewer::Viewer::CullThreadPerCameraDrawThreadPerContext);

    unsigned int screenNum;
    while (arguments.read("--screen",screenNum))
    {
        viewer.setUpViewOnSingleScreen(screenNum);
    }

    // load the data
    osg::ref_ptr<osg::Node> loadedModel = osgDB::readNodeFiles(arguments);
    if (!loadedModel) 
    {
        std::cout << arguments.getApplicationName() <<": No data loaded" << std::endl;
        return 1;
    }

    // any option left unread are converted into errors to write out later.
    arguments.reportRemainingOptionsAsUnrecognized();

    // report any errors if they have occurred when parsing the program arguments.
    if (arguments.errors())
    {
        arguments.writeErrorMessages(std::cout);
        return 1;
    }


    // optimize the scene graph, remove redundant nodes and state etc.
    osgUtil::Optimizer optimizer;
    optimizer.optimize(loadedModel.get());

    viewer.setSceneData( loadedModel.get() );

    return viewer.run();
}