/* OpenSceneGraph example, osgcamera.
*
*  Permission is hereby granted, free of charge, to any person obtaining a copy
*  of this software and associated documentation files (the "Software"), to deal
*  in the Software without restriction, including without limitation the rights
*  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
*  copies of the Software, and to permit persons to whom the Software is
*  furnished to do so, subject to the following conditions:
*
*  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
*  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
*  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
*  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
*  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
*  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
*  THE SOFTWARE.
*/


#include <osgDB/ReadFile>
#include <osgDB/WriteFile>
#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>
#include <osgGA/TrackballManipulator>
#include <osgGA/FlightManipulator>
#include <osgGA/AnimationPathManipulator>
#include <osgGA/GUIEventHandler>
#include <osgGA/StateSetManipulator>
#include <osg/PolygonMode>
#include <osgUtil/Optimizer>
#include <osg/Depth>
#include <iostream>
#include <osg/Switch>
#include <osgSim/MultiSwitch>
#include <osgSim/DOFTransform>

#include <osg/AlphaFunc>
#include <osg/BlendFunc>

using namespace osg;
using namespace osgGA;


class SwitchDOFVisitor : public osg::NodeVisitor, public osgGA::GUIEventHandler 
{
public:
    SwitchDOFVisitor():
      osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN)
    {
    }

    SwitchDOFVisitor(const SwitchDOFVisitor& sdfv, const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY) {}

    META_Object(osg, SwitchDOFVisitor)
    
    virtual void apply(Group& node)
    {
        osgSim::MultiSwitch* pMSwitch = dynamic_cast<osgSim::MultiSwitch*>(&node);
        
        if (pMSwitch)
        {
            mSwitches.push_back(pMSwitch);
        }

        osg::NodeVisitor::apply(node);
    }
    
    virtual void apply(Transform& node)
    {
        osgSim::DOFTransform* pDof = dynamic_cast<osgSim::DOFTransform*>(&node);
        
        if (pDof)
        {
            mDofs.push_back(pDof);
            pDof->setAnimationOn(true);
        }

        osg::NodeVisitor::apply(node);
    }

    void nextSwitch()
    {
        for (size_t i=0; i < mSwitches.size(); i++)
        {
            if (mSwitches[i]->getSwitchSetList().size() > 1)
            {
                // Toggle through switchsets
                unsigned int nextSwitchSet = mSwitches[i]->getActiveSwitchSet();
                nextSwitchSet++;
                if (nextSwitchSet >= mSwitches[i]->getSwitchSetList().size())
                    nextSwitchSet = 0;
                mSwitches[i]->setActiveSwitchSet(nextSwitchSet);
            }
            else if (mSwitches[i]->getSwitchSetList().size() == 1)
            {
                // If we have only one switchset, toggle values within this switchset
                osgSim::MultiSwitch::ValueList values = mSwitches[i]->getValueList(0);
                for (size_t j=0; j < values.size(); j++)
                {
                    if (values[j])
                    {
                        unsigned int nextValue = j+1;
                        if (nextValue >= values.size())
                            nextValue = 0;
                        mSwitches[i]->setSingleChildOn(0, nextValue);
                    }
                }
            }
        }
    }

    void multiplyAnimation(float scale)
    {
        for (size_t i=0; i < mDofs.size(); i++)
        {
            mDofs[i]->setIncrementHPR(mDofs[i]->getIncrementHPR() * scale);
            mDofs[i]->setIncrementScale(mDofs[i]->getIncrementScale() * scale);
            mDofs[i]->setIncrementTranslate(mDofs[i]->getIncrementTranslate() * scale);
        }
    }

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

        if (ea.getHandled()) return false;

        if(ea.getEventType()==GUIEventAdapter::KEYDOWN)
        {

            switch( ea.getKey() )
            {
                case osgGA::GUIEventAdapter::KEY_Right:
                    // Toggle next switch
                    nextSwitch();
                    return true;
                    break;
                case osgGA::GUIEventAdapter::KEY_Up:
                    // Increase animation speed
                    multiplyAnimation(2);
                    return true;
                    break;
                case osgGA::GUIEventAdapter::KEY_Down:
                    // Decrease animation speed
                    multiplyAnimation(0.5);
                    return true;
                    break;
            }
        }
        return false;
    }

private:
    std::vector<osgSim::MultiSwitch*> mSwitches;
    std::vector<osgSim::DOFTransform*> mDofs;
};

void singleWindowSideBySideCameras(osgViewer::Viewer& viewer)
{
    osg::GraphicsContext::WindowingSystemInterface* wsi = osg::GraphicsContext::getWindowingSystemInterface();
    if (!wsi) 
    {
        osg::notify(osg::NOTICE)<<"Error, no WindowSystemInterface available, cannot create windows."<<std::endl;
        return;
    }
    
    unsigned int width, height;
    wsi->getScreenResolution(osg::GraphicsContext::ScreenIdentifier(0), width, height);



    // Not fullscreen
    width /= 2;
    height /= 2;

    osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
    traits->x = 100;
    traits->y = 100;
    traits->width = width;
    traits->height = height;
    traits->windowDecoration = true;
    traits->doubleBuffer = true;
    traits->sharedContext = 0;

    osg::ref_ptr<osg::GraphicsContext> gc = osg::GraphicsContext::createGraphicsContext(traits.get());
    if (gc.valid())
    {
        osg::notify(osg::INFO)<<"  GraphicsWindow has been created successfully."<<std::endl;

        // need to ensure that the window is cleared make sure that the complete window is set the correct colour
        // rather than just the parts of the window that are under the camera's viewports
        gc->setClearColor(osg::Vec4f(0.2f,0.2f,0.6f,1.0f));
        gc->setClearMask(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    }
    else
    {
        osg::notify(osg::NOTICE)<<"  GraphicsWindow has not been created successfully."<<std::endl;
    }


    osg::Camera* master = viewer.getCamera();

    // get the default settings for the camera
    double fovy, aspectRatio, zNear, zFar;
    master->getProjectionMatrixAsPerspective(fovy, aspectRatio, zNear, zFar);

    // reset this for the actual apsect ratio of out created window
    double windowAspectRatio = double(width)/double(height);
    master->setProjectionMatrixAsPerspective(fovy, windowAspectRatio, 1.0, 10000.0);

    master->setName("MasterCam");

    osg::ref_ptr<osg::Camera> camera = new osg::Camera;
    camera->setCullMask(1);
    camera->setName("Left");
    camera->setGraphicsContext(gc.get());
    camera->setViewport(new osg::Viewport(0, 0, width/2, height));
    GLenum buffer = traits->doubleBuffer ? GL_BACK : GL_FRONT;
    camera->setDrawBuffer(buffer);
    camera->setReadBuffer(buffer);
    viewer.addSlave(camera.get(), osg::Matrixd::scale(1.0,0.5,1.0), osg::Matrixd());

    camera = new osg::Camera;
    camera->setCullMask(2);
    camera->setName("Right");
    camera->setGraphicsContext(gc.get());
    camera->setViewport(new osg::Viewport(width/2, 0, width/2, height));
    buffer = traits->doubleBuffer ? GL_BACK : GL_FRONT;
    camera->setDrawBuffer(buffer);
    camera->setReadBuffer(buffer);
    viewer.addSlave(camera.get(), osg::Matrixd::scale(1.0,0.5,1.0), osg::Matrixd());
}

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

    if (argc<2) 
    {
        std::cout << argv[0] <<": requires filename argument." << std::endl;
        return 1;
    }

    osgViewer::Viewer viewer(arguments);
    
    std::string outputfile("output.osgt");
    while (arguments.read("-o",outputfile)) {}

    while (arguments.read("-s")) { viewer.setThreadingModel(osgViewer::Viewer::SingleThreaded); }
    while (arguments.read("-g")) { viewer.setThreadingModel(osgViewer::Viewer::CullDrawThreadPerContext); }
    while (arguments.read("-d")) { viewer.setThreadingModel(osgViewer::Viewer::DrawThreadPerContext); }
    while (arguments.read("-c")) { viewer.setThreadingModel(osgViewer::Viewer::CullThreadPerCameraDrawThreadPerContext); }
    
    singleWindowSideBySideCameras(viewer);

    viewer.setCameraManipulator( new osgGA::TrackballManipulator() );
    viewer.addEventHandler(new osgViewer::StatsHandler);
    viewer.addEventHandler(new osgViewer::ThreadingHandler);
    viewer.addEventHandler(new osgViewer::WindowSizeHandler());
    viewer.addEventHandler(new osgViewer::LODScaleHandler());
    viewer.addEventHandler(new osgGA::StateSetManipulator());

    SwitchDOFVisitor* visit = new SwitchDOFVisitor;
    viewer.addEventHandler(visit);
    
    osg::ref_ptr<osg::Node> loadedModel;
    // load the scene.
    loadedModel = osgDB::readNodeFiles(arguments);

    if (!loadedModel) 
    {
        std::cout << argv[0] <<": No data loaded." << std::endl;
        return 1;
    }

    osg::Group* group = new osg::Group;
    
    osg::Group* group1 = new osg::Group;
    group1->addChild(loadedModel.get());
    group1->setNodeMask(1);

    // Uncomment these lines if you like to compare the loaded model to the resulting model in a merge/diff tool
    //osgDB::writeNodeFile(*loadedModel.get(), "dummy1.osgt");

    osgDB::writeNodeFile(*loadedModel.get(), outputfile);
    osg::ref_ptr<osg::Node> convertedModel = osgDB::readNodeFile(outputfile);

    //osgDB::writeNodeFile(*convertedModel.get(), "dummy2.osgt");

    osg::Group* group2 = new osg::Group;
    group2->addChild(convertedModel.get());
    group2->setNodeMask(2);

    // Activate DOF animations and collect switches
    loadedModel->accept(*visit);
    convertedModel->accept(*visit);

    group->addChild(group1);
    group->addChild(group2);

    viewer.setSceneData(group);

    viewer.setThreadingModel(osgViewer::Viewer::DrawThreadPerContext);
    viewer.realize();

    viewer.run();

    return 0;
}