/*  -*-c++-*- 
 *  Copyright (C) 2009 Cedric Pinson <cedric.pinson@plopbyte.net>
 *
 * 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.
*/

#include <iostream>
#include <osgDB/ReadFile>
#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 <osg/Drawable>
#include <osg/MatrixTransform>

#include <osgAnimation/BasicAnimationManager>
#include <osgAnimation/RigGeometry>
#include <osgAnimation/RigTransformHardware>
#include <osgAnimation/AnimationManagerBase>

#include <sstream>


static unsigned int getRandomValueinRange(unsigned int v)
{
    return static_cast<unsigned int>((rand() * 1.0 * v)/(RAND_MAX-1));
}


osg::ref_ptr<osg::Program> program;
// show how to override the default RigTransformHardware for customized usage
struct MyRigTransformHardware : public osgAnimation::RigTransformHardware
{
    bool init(osgAnimation::RigGeometry& geom)
    {
        osg::Vec3Array* pos = dynamic_cast<osg::Vec3Array*>(geom.getVertexArray());
        if (!pos) {
            osg::notify(osg::WARN) << "RigTransformHardware no vertex array in the geometry " << geom.getName() << std::endl;
            return false;
        }

        if (!geom.getSkeleton()) {
            osg::notify(osg::WARN) << "RigTransformHardware no skeleting set in geometry " << geom.getName() << std::endl;
            return false;
        }

        osgAnimation::Bone::BoneMap bm = geom.getSkeleton()->getBoneMap();

        if (!createPalette(pos->size(),bm, geom.getVertexInfluenceSet().getVertexToBoneList()))
            return false;

        int attribIndex = 11;
        int nbAttribs = getNumVertexAttrib();

        // use a global program for all avatar
        if (!program.valid()) {
            program = new osg::Program;
            program->setName("HardwareSkinning");
            if (!_shader.valid())
                _shader = osg::Shader::readShaderFile(osg::Shader::VERTEX,"shaders/skinning.vert");

            if (!_shader.valid()) {
                osg::notify(osg::WARN) << "RigTransformHardware can't load VertexShader" << std::endl;
                return false;
            }

            // replace max matrix by the value from uniform
            {
                std::string str = _shader->getShaderSource();
                std::string toreplace = std::string("MAX_MATRIX");
                std::size_t start = str.find(toreplace);
                std::stringstream ss;
                ss << getMatrixPaletteUniform()->getNumElements();
                str.replace(start, toreplace.size(), ss.str());
                _shader->setShaderSource(str);
                osg::notify(osg::INFO) << "Shader " << str << std::endl;
            }

            program->addShader(_shader.get());

            for (int i = 0; i < nbAttribs; i++)
            {
                std::stringstream ss;
                ss << "boneWeight" << i;
                program->addBindAttribLocation(ss.str(), attribIndex + i);

                osg::notify(osg::INFO) << "set vertex attrib " << ss.str() << std::endl;
            }
        } 
        for (int i = 0; i < nbAttribs; i++)
        {
            std::stringstream ss;
            ss << "boneWeight" << i;
            geom.setVertexAttribData(attribIndex + i, osg::Geometry::ArrayData(getVertexAttrib(i),osg::Geometry::BIND_PER_VERTEX));
        }

        osg::ref_ptr<osg::StateSet> ss = new osg::StateSet;
        ss->addUniform(getMatrixPaletteUniform());
        ss->addUniform(new osg::Uniform("nbBonesPerVertex", getNumBonesPerVertex()));
        ss->setAttributeAndModes(program.get());
        geom.setStateSet(ss.get());
        _needInit = false;
        return true;
    }

};


struct SetupRigGeometry : public osg::NodeVisitor
{
    bool _hardware;
    SetupRigGeometry( bool hardware = true) : osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN), _hardware(hardware) {}
    
    void apply(osg::Geode& geode)
    {
        for (unsigned int i = 0; i < geode.getNumDrawables(); i++)
            apply(*geode.getDrawable(i));
    }
    void apply(osg::Drawable& geom)
    {
        if (_hardware) {
            osgAnimation::RigGeometry* rig = dynamic_cast<osgAnimation::RigGeometry*>(&geom);
            if (rig)
                rig->setRigTransformImplementation(new MyRigTransformHardware);
        }

        if (geom.getName() != std::string("BoundingBox")) // we disable compute of bounding box for all geometry except our bounding box
            geom.setComputeBoundingBoxCallback(new osg::Drawable::ComputeBoundingBoxCallback);
    }
};

osg::Group* createCharacterInstance(osg::Group* character, bool hardware)
{
    osg::ref_ptr<osg::Group> c ;
    if (hardware)
        c = osg::clone(character, osg::CopyOp::DEEP_COPY_ALL & ~osg::CopyOp::DEEP_COPY_PRIMITIVES & ~osg::CopyOp::DEEP_COPY_ARRAYS);
    else
        c = osg::clone(character, osg::CopyOp::DEEP_COPY_ALL);

    osgAnimation::AnimationManagerBase* animationManager = dynamic_cast<osgAnimation::AnimationManagerBase*>(c->getUpdateCallback());

    osgAnimation::BasicAnimationManager* anim = dynamic_cast<osgAnimation::BasicAnimationManager*>(animationManager);
    const osgAnimation::AnimationList& list = animationManager->getAnimationList();
    int v = getRandomValueinRange(list.size());
    if (list[v]->getName() == std::string("MatIpo_ipo")) {
        anim->playAnimation(list[v].get());
        v = (v + 1)%list.size();
    }
        
    anim->playAnimation(list[v].get());

    SetupRigGeometry switcher(hardware);
    c->accept(switcher);

    return c.release();
}


int main (int argc, char* argv[])
{
    std::cerr << "This example works better with nathan.osg" << std::endl;

    osg::ArgumentParser psr(&argc, argv);

    osgViewer::Viewer viewer(psr);

    bool hardware = true;
    int maxChar = 10;
    while (psr.read("--software")) { hardware = false; }
    while (psr.read("--number", maxChar)) {}


    osg::ref_ptr<osg::Group> root = dynamic_cast<osg::Group*>(osgDB::readNodeFiles(psr));
    if (!root) 
    {
        std::cout << psr.getApplicationName() <<": No data loaded" << std::endl;
        return 1;
    }

    {
        osgAnimation::AnimationManagerBase* animationManager = dynamic_cast<osgAnimation::AnimationManagerBase*>(root->getUpdateCallback());
        if(!animationManager) 
        {
            osg::notify(osg::FATAL) << "no AnimationManagerBase found, updateCallback need to animate elements" << std::endl;
            return 1;
        }
    }


    osg::ref_ptr<osg::Group> scene = new osg::Group;

    // 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(psr.getApplicationUsage()));

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

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

    viewer.setSceneData(scene.get());

    viewer.realize();

    int xChar = maxChar;
    int yChar = xChar * 9.0/16;
    for (int i = 0; i < xChar; i++) {
        for (int j = 0; j < yChar; j++) {

            osg::ref_ptr<osg::Group> c = createCharacterInstance(root.get(), hardware);
            osg::MatrixTransform* tr = new osg::MatrixTransform;
            tr->setMatrix(osg::Matrix::translate( 2 * (i - xChar * .5),
                                                  0,
                                                  2 * (j - yChar * .5)));
            tr->addChild(c.get());
            scene->addChild(tr);
        }
    }
    std::cout << "created " << xChar * yChar << " instance"  << std::endl;


    return viewer.run();
}


