/* -*-c++-*- OpenSceneGraph - Copyright (C) Sketchfab */

#ifndef SUB_GEOMETRY
#define SUB_GEOMETRY

#include <map>

#include <osg/Object>
#include <osg/Array>
#include <osg/Geometry>
#include <osg/StateSet>
#include <osg/ref_ptr>

#include <osgAnimation/MorphGeometry>


class SubGeometry {
public:
    typedef std::map<osg::Array*, const osg::Array*>::iterator BufferIterator;
    typedef std::map<unsigned int, unsigned int> IndexMapping;

    SubGeometry(const osg::Geometry& source,
                const std::vector<unsigned int>& triangles,
                const std::vector<unsigned int>& lines,
                const std::vector<unsigned int>& wireframe,
                const std::vector<unsigned int>& points)
    {
        // Create new geometry as we will modify vertex arrays and primitives (the process is
        // equivalent to deep cloning).
        // As UserValues might be changed on a per-geometry basis afterwards, we deep clone userdata
        // We do *not* want to clone statesets as they reference a UniqueID that should be unique
        // (see #83056464).
        if(dynamic_cast<const osgAnimation::MorphGeometry*>(&source)) {
            _geometry = new osgAnimation::MorphGeometry;
        }
        else {
            _geometry = new osg::Geometry;
        }

        if(source.getUserDataContainer()) {
            _geometry->setUserDataContainer(osg::clone(source.getUserDataContainer(), osg::CopyOp::DEEP_COPY_ALL));
        }

        if(source.getStateSet()) {
            _geometry->setStateSet(const_cast<osg::StateSet*>(source.getStateSet()));
        }

        addSourceBuffers(_geometry.get(), source);

        // process morph targets if needed
        if(const osgAnimation::MorphGeometry* morphSource = dynamic_cast<const osgAnimation::MorphGeometry*>(&source)) {
            osgAnimation::MorphGeometry* morph = dynamic_cast<osgAnimation::MorphGeometry*>(_geometry.get());
            const osgAnimation::MorphGeometry::MorphTargetList& morphTargetList = morphSource->getMorphTargetList();

            osgAnimation::MorphGeometry::MorphTargetList::const_iterator targetSource;
            for(targetSource = morphTargetList.begin() ; targetSource != morphTargetList.end() ; ++ targetSource) {
                if(targetSource->getGeometry()) {
                    osg::Geometry* target = new osg::Geometry;
                    addSourceBuffers(target, *targetSource->getGeometry());
                    morph->addMorphTarget(target, targetSource->getWeight());
                }
            }
        }

        // remap primitives indices by decreasing ordering (triangles > lines > wireframe > points)
        for(unsigned int i = 0 ; i < triangles.size() ; i += 3) {
            copyTriangle(triangles[i], triangles[i + 1], triangles[i + 2]);
        }

        for(unsigned int i = 0 ; i < lines.size() ; i += 2) {
            copyEdge(lines[i], lines[i + 1], false);
        }

        for(unsigned int i = 0 ; i < wireframe.size() ; i += 2) {
            copyEdge(wireframe[i], wireframe[i + 1], true);
        }

        for(unsigned int i = 0 ; i < points.size() ; ++ i) {
            copyPoint(points[i]);
        }

        // remap vertex buffers accordingly to primitives
        for(BufferIterator it = _bufferMap.begin() ; it != _bufferMap.end() ; ++ it) {
            if(it->first) {
                copyFrom(*(it->second), *(it->first));
            }
        }
    }

    osg::Geometry* geometry() const {
        return _geometry.get();
    }

protected:
    void addSourceBuffers(osg::Geometry* geometry, const osg::Geometry& source) {
        // create necessary vertex containers
        const osg::Array* array = 0;

        geometry->setName(source.getName());

        // collect all buffers that are BIND_PER_VERTEX for eventual vertex duplication
        if( (array = vertexArray(source.getVertexArray()))  ) {
            geometry->setVertexArray(makeVertexBuffer(array));
        }

        if( (array = vertexArray(source.getNormalArray())) ){
            geometry->setNormalArray(makeVertexBuffer(array));
        }

        if( (array = vertexArray(source.getColorArray())) ){
            geometry->setColorArray(makeVertexBuffer(array));
        }

        if( (array = vertexArray(source.getSecondaryColorArray())) ){
            geometry->setSecondaryColorArray(makeVertexBuffer(array));
        }

        if( (array = vertexArray(source.getFogCoordArray())) ){
            geometry->setFogCoordArray(makeVertexBuffer(array));
        }

        for(unsigned int i = 0; i < source.getNumVertexAttribArrays(); ++ i) {
            if( (array = vertexArray(source.getVertexAttribArray(i))) ){
                geometry->setVertexAttribArray(i, makeVertexBuffer(array));
            }
        }

        for(unsigned int i = 0; i < source.getNumTexCoordArrays(); ++ i) {
            if( (array = vertexArray(source.getTexCoordArray(i))) ){
                geometry->setTexCoordArray(i, makeVertexBuffer(array));
            }
        }
    }

    void copyTriangle(unsigned int v1, unsigned int v2, unsigned int v3) {
        osg::DrawElements* triangles = getOrCreateTriangles();
        triangles->addElement(mapVertex(v1));
        triangles->addElement(mapVertex(v2));
        triangles->addElement(mapVertex(v3));
    }

    void copyEdge(unsigned int v1, unsigned int v2, bool wireframe) {
        osg::DrawElements* edges = getOrCreateLines(wireframe);
        edges->addElement(mapVertex(v1));
        edges->addElement(mapVertex(v2));
    }

    void copyPoint(unsigned int v1) {
        osg::DrawElements* points = getOrCreatePoints();
        points->addElement(mapVertex(v1));
    }

    const osg::Array* vertexArray(const osg::Array* array) {
        // filter invalid vertex buffers
        if (array && array->getNumElements() && array->getBinding() == osg::Array::BIND_PER_VERTEX) {
            return array;
        }
        else {
            return 0;
        }
    }

    inline osg::Array* makeVertexBuffer(const osg::Array* array, bool copyUserData=true) {
        osg::Array* buffer = 0;
        if(array) {
            buffer = dynamic_cast<osg::Array*>(array->cloneType());
            buffer->setBinding(osg::Array::BIND_PER_VERTEX);
            if(copyUserData && array->getUserDataContainer()) {
                buffer->setUserDataContainer(osg::clone(array->getUserDataContainer(), osg::CopyOp::DEEP_COPY_ALL));
            }
            _bufferMap[buffer] = array;
        }
        return buffer;
    }


    template<typename C>
    void copyValues(const C& src, C& dst) {
        dst.resize(_indexMap.size());
        for(IndexMapping::const_iterator remapper = _indexMap.begin() ; remapper != _indexMap.end() ; ++ remapper) {
            dst[remapper->second] = src[remapper->first];
        }
    }

#define COPY_TEMPLATE(T) \
    if (dynamic_cast<const T*>(&src)) \
    { return copyValues<T>(dynamic_cast<const T&>(src), dynamic_cast<T&>(dst)); }

    void copyFrom(const osg::Array& src, osg::Array& dst) {
        COPY_TEMPLATE(osg::Vec2Array);
        COPY_TEMPLATE(osg::Vec3Array);
        COPY_TEMPLATE(osg::Vec4Array);

        COPY_TEMPLATE(osg::Vec2dArray);
        COPY_TEMPLATE(osg::Vec3dArray);
        COPY_TEMPLATE(osg::Vec4dArray);

        COPY_TEMPLATE(osg::ByteArray);
        COPY_TEMPLATE(osg::ShortArray);
        COPY_TEMPLATE(osg::IntArray);
        COPY_TEMPLATE(osg::UByteArray);
        COPY_TEMPLATE(osg::UShortArray);
        COPY_TEMPLATE(osg::UIntArray);
        COPY_TEMPLATE(osg::FloatArray);
        COPY_TEMPLATE(osg::DoubleArray);

        COPY_TEMPLATE(osg::Vec2iArray);
        COPY_TEMPLATE(osg::Vec3iArray);
        COPY_TEMPLATE(osg::Vec4iArray);

        COPY_TEMPLATE(osg::Vec2uiArray);
        COPY_TEMPLATE(osg::Vec3uiArray);
        COPY_TEMPLATE(osg::Vec4uiArray);

        COPY_TEMPLATE(osg::Vec2sArray);
        COPY_TEMPLATE(osg::Vec3sArray);
        COPY_TEMPLATE(osg::Vec4sArray);

        COPY_TEMPLATE(osg::Vec2usArray);
        COPY_TEMPLATE(osg::Vec3usArray);
        COPY_TEMPLATE(osg::Vec4usArray);

        COPY_TEMPLATE(osg::Vec2bArray);
        COPY_TEMPLATE(osg::Vec3bArray);
        COPY_TEMPLATE(osg::Vec4bArray);

        COPY_TEMPLATE(osg::Vec2ubArray);
        COPY_TEMPLATE(osg::Vec3ubArray);
        COPY_TEMPLATE(osg::Vec4ubArray);

        COPY_TEMPLATE(osg::MatrixfArray);

        COPY_TEMPLATE(osg::QuatArray);
    }

    unsigned int mapVertex(unsigned int i) {
        if(_indexMap.find(i) == _indexMap.end()) {
            unsigned int index = _indexMap.size();
            _indexMap[i] = index;
        }
        return _indexMap[i];
    }

    osg::DrawElements* getOrCreateTriangles() {
        if(_primitives.find("triangles") == _primitives.end()) {
            _primitives["triangles"] = new osg::DrawElementsUInt(GL_TRIANGLES);
            _geometry->addPrimitiveSet(_primitives["triangles"]);
        }
        return _primitives["triangles"];
    }

    osg::DrawElements* getOrCreateLines(bool wireframe) {
        std::string label = wireframe ? "wireframe" : "lines";

        if(_primitives.find(label) == _primitives.end()) {
            _primitives[label] = new osg::DrawElementsUInt(GL_LINES);
            if(wireframe) {
                _primitives[label]->setUserValue("wireframe", true);
            }
            _geometry->addPrimitiveSet(_primitives[label]);
        }
        return _primitives[label];
    }

    osg::DrawElements* getOrCreatePoints() {
        if(_primitives.find("points") == _primitives.end()) {
            _primitives["points"] = new osg::DrawElementsUInt(GL_POINTS);
            _geometry->addPrimitiveSet(_primitives["points"]);
        }
        return _primitives["points"];
    }

    osg::ref_ptr<osg::Geometry> _geometry;
    std::map<osg::Array*, const osg::Array*> _bufferMap;
    std::map<unsigned int, unsigned int> _indexMap;
    std::map<std::string, osg::DrawElements*> _primitives;
};


#endif