/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2010 Robert Osfield
 *
 * This application is open source and may be redistributed and/or modified
 * freely and without restriction, both in commercial and non commercial 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/ViewerEventHandlers>

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

#include <osgGA/Device>

#include <iostream>

#include <osg/GLExtensions>

#ifndef GL_ARB_sync
#define GL_MAX_SERVER_WAIT_TIMEOUT        0x9111
#define GL_OBJECT_TYPE                    0x9112
#define GL_SYNC_CONDITION                 0x9113
#define GL_SYNC_STATUS                    0x9114
#define GL_SYNC_FLAGS                     0x9115
#define GL_SYNC_FENCE                     0x9116
#define GL_SYNC_GPU_COMMANDS_COMPLETE     0x9117
#define GL_UNSIGNALED                     0x9118
#define GL_SIGNALED                       0x9119
#define GL_ALREADY_SIGNALED               0x911A
#define GL_TIMEOUT_EXPIRED                0x911B
#define GL_CONDITION_SATISFIED            0x911C
#define GL_WAIT_FAILED                    0x911D
#define GL_SYNC_FLUSH_COMMANDS_BIT        0x00000001
#define GL_TIMEOUT_IGNORED                0xFFFFFFFFFFFFFFFFull
#endif

class MySwapBuffersCallback : public osg::GraphicsContext::SwapCallback
{
public:
    MySwapBuffersCallback():
        _extensionInitialized(false),
        _glFenceSync(0),
        _glIsSync(0),
        _glDeleteSync(0),
        _glClientWaitSync(0),
        _glWaitSync(0),
        _glGetInteger64v(0),
        _glGetSynciv(0),
        _previousSync(0)
    {
         OSG_NOTICE<<"Created Swap callback."<<std::endl;
    }

    void setUpExtensions()
    {
        _extensionInitialized = true;
        osg::setGLExtensionFuncPtr(_glFenceSync, "glFenceSync");
        osg::setGLExtensionFuncPtr(_glIsSync, "glIsSync");
        osg::setGLExtensionFuncPtr(_glDeleteSync, "glDeleteSync");
        osg::setGLExtensionFuncPtr(_glClientWaitSync, "glClientWaitSync");
        osg::setGLExtensionFuncPtr(_glWaitSync, "glWaitSync");
        osg::setGLExtensionFuncPtr(_glGetInteger64v, "glGetInteger64v");
        osg::setGLExtensionFuncPtr(_glGetSynciv, "glGetSynciv");
    }

    virtual void swapBuffersImplementation(osg::GraphicsContext* gc)
    {
        // OSG_NOTICE<<"Before swap - place to do swap ready sync"<<std::endl;
        gc->swapBuffersImplementation();
        //glFinish();

        if (!_extensionInitialized) setUpExtensions();

        if (_glClientWaitSync)
        {        
            if (_previousSync)
            {
                unsigned int num_seconds = 1;
		GLuint64EXT timeout = num_seconds * ((GLuint64EXT)1000 * 1000 * 1000);
                _glClientWaitSync(_previousSync, 0, timeout);

                _glDeleteSync(_previousSync);
            }

            _previousSync = _glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
        }
        //gc->getState()->checkGLErrors("after glWaitSync");

        //OSG_NOTICE<<"After swap"<<std::endl;
    }

    typedef struct __GLsync *GLsync;

    typedef GLsync (GL_APIENTRY * PFNGLFENCESYNCPROC) (GLenum condition, GLbitfield flags);
    typedef GLboolean (GL_APIENTRY * PFNGLISSYNCPROC) (GLsync sync);
    typedef void (GL_APIENTRY * PFNGLDELETESYNCPROC) (GLsync sync);
    typedef GLenum (GL_APIENTRY * PFNGLCLIENTWAITSYNCPROC) (GLsync sync, GLbitfield flags, GLuint64EXT timeout);
    typedef void (GL_APIENTRY * PFNGLWAITSYNCPROC) (GLsync sync, GLbitfield flags, GLuint64EXT timeout);
    typedef void (GL_APIENTRY * PFNGLGETINTEGER64VPROC) (GLenum pname, GLint64EXT *params);
    typedef void (GL_APIENTRY * PFNGLGETSYNCIVPROC) (GLsync sync, GLenum pname, GLsizei bufSize, GLsizei *length, GLint *values);

    bool                        _extensionInitialized;
    
    PFNGLFENCESYNCPROC          _glFenceSync;
    PFNGLISSYNCPROC             _glIsSync;
    PFNGLDELETESYNCPROC         _glDeleteSync;
    PFNGLCLIENTWAITSYNCPROC     _glClientWaitSync;
    PFNGLWAITSYNCPROC           _glWaitSync;
    PFNGLGETINTEGER64VPROC      _glGetInteger64v;
    PFNGLGETSYNCIVPROC          _glGetSynciv;

    GLsync _previousSync;
};

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("--login <url> <username> <password>","Provide authentication information for http file access.");
    arguments.getApplicationUsage()->addCommandLineOption("-p <filename>","Play specified camera path animation file, previously saved with 'z' key.");
    arguments.getApplicationUsage()->addCommandLineOption("--speed <factor>","Speed factor for animation playing (1 == normal speed).");
    arguments.getApplicationUsage()->addCommandLineOption("--device <device-name>","add named device to the viewer");

    osgViewer::Viewer viewer(arguments);

    unsigned int helpType = 0;
    if ((helpType = arguments.readHelpType()))
    {
        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;
    }

    std::string url, username, password;
    while(arguments.read("--login",url, username, password))
    {
        if (!osgDB::Registry::instance()->getAuthenticationMap())
        {
            osgDB::Registry::instance()->setAuthenticationMap(new osgDB::AuthenticationMap);
            osgDB::Registry::instance()->getAuthenticationMap()->addAuthenticationDetails(
                url,
                new osgDB::AuthenticationDetails(username, password)
            );
        }
    }
    
    std::string device;
    while(arguments.read("--device", device))
    {
        osg::ref_ptr<osgGA::Device> dev = osgDB::readFile<osgGA::Device>(device);
        if (dev.valid())
        {
            viewer.addDevice(dev.get());
        }
    }

    // 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() );
        keyswitchManipulator->addMatrixManipulator( '5', "Orbit", new osgGA::OrbitManipulator() );
        keyswitchManipulator->addMatrixManipulator( '6', "FirstPerson", new osgGA::FirstPersonManipulator() );
        keyswitchManipulator->addMatrixManipulator( '7', "Spherical", new osgGA::SphericalManipulator() );

        std::string pathfile;
        double animationSpeed = 1.0;
        while(arguments.read("--speed",animationSpeed) ) {}
        char keyForAnimationPath = '8';
        while (arguments.read("-p",pathfile))
        {
            osgGA::AnimationPathManipulator* apm = new osgGA::AnimationPathManipulator(pathfile);
            if (apm || !apm->valid())
            {
                apm->setTimeScale(animationSpeed);

                unsigned int num = keyswitchManipulator->getNumMatrixManipulators();
                keyswitchManipulator->addMatrixManipulator( keyForAnimationPath, "Path", apm );
                keyswitchManipulator->selectMatrixManipulator(num);
                ++keyForAnimationPath;
            }
        }

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

    bool doArbSync = arguments.read("--sync");

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

    // add the thread model handler
    viewer.addEventHandler(new osgViewer::ThreadingHandler);

    // add the window size toggle handler
    viewer.addEventHandler(new osgViewer::WindowSizeHandler);

    // add the stats handler
    viewer.addEventHandler(new osgViewer::StatsHandler);

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

    // add the record camera path handler
    viewer.addEventHandler(new osgViewer::RecordCameraPathHandler);

    // add the LOD Scale handler
    viewer.addEventHandler(new osgViewer::LODScaleHandler);

    // add the screen capture handler
    viewer.addEventHandler(new osgViewer::ScreenCaptureHandler);

    // 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() );

    viewer.realize();

    if (doArbSync)
    {
        osgViewer::ViewerBase::Contexts contexts;
        viewer.getContexts(contexts);
        for(osgViewer::ViewerBase::Contexts::iterator itr = contexts.begin();
            itr != contexts.end();
            ++itr)
        {
            (*itr)->setSwapCallback(new MySwapBuffersCallback);
        }
    }

    return viewer.run();

}