/*=========================================================================

   Library: iMSTK

   Copyright (c) Kitware, Inc. & Center for Modeling, Simulation,
   & Imaging in Medicine, Rensselaer Polytechnic Institute.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0.txt

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

=========================================================================*/

#include "imstkCamera.h"
#include "imstkDirectionalLight.h"
#include "imstkImageData.h"
#include "imstkKeyboardDeviceClient.h"
#include "imstkKeyboardSceneControl.h"
#include "imstkLineMesh.h"
#include "imstkMeshIO.h"
#include "imstkMeshToMeshBruteForceCD.h"
#include "imstkMouseSceneControl.h"
#include "imstkNew.h"
#include "imstkOneToOneMap.h"
#include "imstkPbdModel.h"
#include "imstkPbdObject.h"
#include "imstkRbdConstraint.h"
#include "imstkRenderMaterial.h"
#include "imstkRigidBodyModel2.h"
#include "imstkRigidObject2.h"
#include "imstkScene.h"
#include "imstkSceneManager.h"
#include "imstkSimulationManager.h"
#include "imstkSurfaceMesh.h"
#include "imstkTetrahedralMesh.h"
#include "imstkVisualModel.h"
#include "imstkVTKViewer.h"

// If two-way coupling is used haptic forces can be felt when the tool
// hits the tissue
#define TWOWAY_COUPLING

// Whether to use FEM or volume+distance constraints
#define USE_FEM

#ifdef TWOWAY_COUPLING
#include "imstkPbdRigidObjectCollision.h"
#else
#include "imstkPbdObjectCollision.h"
#endif

#ifdef iMSTK_USE_OPENHAPTICS
#include "imstkHapticDeviceManager.h"
#include "imstkHapticDeviceClient.h"
#include "imstkRigidObjectController.h"
#else
#include "imstkMouseDeviceClient.h"
#endif

using namespace imstk;

///
/// \brief Creates a tetraheral grid
/// \param physical dimension of tissue
/// \param dimensions of tetrahedral grid used for tissue
/// \param center of grid
///
static std::shared_ptr<TetrahedralMesh>
makeTetGrid(const Vec3d& size, const Vec3i& dim, const Vec3d& center)
{
    imstkNew<TetrahedralMesh> tissueMesh;

    imstkNew<VecDataArray<double, 3>> verticesPtr(dim[0] * dim[1] * dim[2]);
    VecDataArray<double, 3>&          vertices = *verticesPtr.get();
    const Vec3d                       dx       = size.cwiseQuotient((dim - Vec3i(1, 1, 1)).cast<double>());
    for (int z = 0; z < dim[2]; z++)
    {
        for (int y = 0; y < dim[1]; y++)
        {
            for (int x = 0; x < dim[0]; x++)
            {
                vertices[x + dim[0] * (y + dim[1] * z)] = Vec3i(x, y, z).cast<double>().cwiseProduct(dx) - size * 0.5 + center;
            }
        }
    }

    // Add connectivity data
    imstkNew<VecDataArray<int, 4>> indicesPtr;
    VecDataArray<int, 4>&          indices = *indicesPtr.get();
    for (int z = 0; z < dim[2] - 1; z++)
    {
        for (int y = 0; y < dim[1] - 1; y++)
        {
            for (int x = 0; x < dim[0] - 1; x++)
            {
                int cubeIndices[8] =
                {
                    x + dim[0] * (y + dim[1] * z),
                    (x + 1) + dim[0] * (y + dim[1] * z),
                    (x + 1) + dim[0] * (y + dim[1] * (z + 1)),
                    x + dim[0] * (y + dim[1] * (z + 1)),
                    x + dim[0] * ((y + 1) + dim[1] * z),
                    (x + 1) + dim[0] * ((y + 1) + dim[1] * z),
                    (x + 1) + dim[0] * ((y + 1) + dim[1] * (z + 1)),
                    x + dim[0] * ((y + 1) + dim[1] * (z + 1))
                };

                // Alternate the pattern so the edges line up on the sides of each voxel
                if ((z % 2 ^ x % 2) ^ y % 2)
                {
                    indices.push_back(Vec4i(cubeIndices[0], cubeIndices[7], cubeIndices[5], cubeIndices[4]));
                    indices.push_back(Vec4i(cubeIndices[3], cubeIndices[7], cubeIndices[2], cubeIndices[0]));
                    indices.push_back(Vec4i(cubeIndices[2], cubeIndices[7], cubeIndices[5], cubeIndices[0]));
                    indices.push_back(Vec4i(cubeIndices[1], cubeIndices[2], cubeIndices[0], cubeIndices[5]));
                    indices.push_back(Vec4i(cubeIndices[2], cubeIndices[6], cubeIndices[7], cubeIndices[5]));
                }
                else
                {
                    indices.push_back(Vec4i(cubeIndices[3], cubeIndices[7], cubeIndices[6], cubeIndices[4]));
                    indices.push_back(Vec4i(cubeIndices[1], cubeIndices[3], cubeIndices[6], cubeIndices[4]));
                    indices.push_back(Vec4i(cubeIndices[3], cubeIndices[6], cubeIndices[2], cubeIndices[1]));
                    indices.push_back(Vec4i(cubeIndices[1], cubeIndices[6], cubeIndices[5], cubeIndices[4]));
                    indices.push_back(Vec4i(cubeIndices[0], cubeIndices[3], cubeIndices[1], cubeIndices[4]));
                }
            }
        }
    }

    imstkNew<VecDataArray<float, 2>> uvCoordsPtr(dim[0] * dim[1] * dim[2]);
    VecDataArray<float, 2>&          uvCoords = *uvCoordsPtr.get();
    for (int z = 0; z < dim[2]; z++)
    {
        for (int y = 0; y < dim[1]; y++)
        {
            for (int x = 0; x < dim[0]; x++)
            {
                uvCoords[x + dim[0] * (y + dim[1] * z)] = Vec2f(static_cast<float>(x) / dim[0], static_cast<float>(z) / dim[2]) * 3.0;
            }
        }
    }

    // Ensure correct windings
    for (int i = 0; i < indices.size(); i++)
    {
        if (tetVolume(vertices[indices[i][0]], vertices[indices[i][1]], vertices[indices[i][2]], vertices[indices[i][3]]) < 0.0)
        {
            std::swap(indices[i][0], indices[i][2]);
        }
    }

    tissueMesh->initialize(verticesPtr, indicesPtr);
    tissueMesh->setVertexTCoords("uvs", uvCoordsPtr);

    return tissueMesh;
}

///
/// \brief Spherically project the texture coordinates
///
static void
setSphereTexCoords(std::shared_ptr<SurfaceMesh> surfMesh, const double uvScale)
{
    Vec3d min, max;
    surfMesh->computeBoundingBox(min, max);
    const Vec3d size   = max - min;
    const Vec3d center = (max + min) * 0.5;

    const double radius = (size * 0.5).norm();

    imstkNew<VecDataArray<float, 2>> uvCoordsPtr(surfMesh->getNumVertices());
    VecDataArray<float, 2>&          uvCoords = *uvCoordsPtr.get();
    for (int i = 0; i < surfMesh->getNumVertices(); i++)
    {
        Vec3d vertex = surfMesh->getVertexPosition(i) - center;

        // Compute phi and theta on the sphere
        const double theta = asin(vertex[0] / radius);
        const double phi   = atan2(vertex[1], vertex[2]);
        uvCoords[i] = Vec2f(phi / (PI * 2.0) + 0.5, theta / (PI * 2.0) + 0.5) * uvScale;
    }
    surfMesh->setVertexTCoords("tcoords", uvCoordsPtr);
}

///
/// \brief Creates tissue object
/// \param name
/// \param physical dimension of tissue
/// \param dimensions of tetrahedral grid used for tissue
/// \param center of tissue block
///
static std::shared_ptr<PbdObject>
makeTissueObj(const std::string& name,
              const Vec3d& size, const Vec3i& dim, const Vec3d& center)
{
    imstkNew<PbdObject> clothObj(name);

    // Setup the Geometry
    std::shared_ptr<TetrahedralMesh> tissueMesh = makeTetGrid(size, dim, center);
    std::shared_ptr<SurfaceMesh>     surfMesh   = tissueMesh->extractSurfaceMesh();
    //setXZPlaneTexCoords(surfMesh, 4.0);
    setSphereTexCoords(surfMesh, 4.0);

    // Setup the Parameters
    imstkNew<PbdModelConfig> pbdParams;
#ifdef USE_FEM
    // Use FEMTet constraints
    pbdParams->m_femParams->m_YoungModulus = 5.0;
    pbdParams->m_femParams->m_PoissonRatio = 0.4;
    pbdParams->enableFEMConstraint(PbdFEMConstraint::MaterialType::StVK);
#else
    // Use volume+distance constraints, worse results. More performant (can use larger mesh)
    pbdParams->enableConstraint(PbdConstraint::Type::Volume, 0.9);
    pbdParams->enableConstraint(PbdConstraint::Type::Distance, 0.95);
#endif
    pbdParams->m_doPartitioning   = true;
    pbdParams->m_uniformMassValue = 0.05;
    pbdParams->m_gravity    = Vec3d(0.0, 0.0, 0.0);
    pbdParams->m_dt         = 0.05;
    pbdParams->m_iterations = 5;
    pbdParams->m_viscousDampingCoeff = 0.1;

    // Fix the borders
    for (int z = 0; z < dim[2]; z++)
    {
        for (int y = 0; y < dim[1]; y++)
        {
            for (int x = 0; x < dim[0]; x++)
            {
                if (x == 0 || /*z == 0 ||*/ x == dim[0] - 1 /*|| z == dim[2] - 1*/)
                {
                    pbdParams->m_fixedNodeIds.push_back(x + dim[0] * (y + dim[1] * z));
                }
            }
        }
    }

    // Setup the Model
    imstkNew<PbdModel> pbdModel;
    pbdModel->setModelGeometry(tissueMesh);
    pbdModel->configure(pbdParams);

    // Setup the material
    imstkNew<RenderMaterial> material;
    material->setShadingModel(RenderMaterial::ShadingModel::PBR);
    auto diffuseTex = MeshIO::read<ImageData>(iMSTK_DATA_ROOT "/textures/fleshDiffuse.jpg");
    material->addTexture(std::make_shared<Texture>(diffuseTex, Texture::Type::Diffuse));
    auto normalTex = MeshIO::read<ImageData>(iMSTK_DATA_ROOT "/textures/fleshNormal.jpg");
    material->addTexture(std::make_shared<Texture>(normalTex, Texture::Type::Normal));
    auto ormTex = MeshIO::read<ImageData>(iMSTK_DATA_ROOT "/textures/fleshORM.jpg");
    material->addTexture(std::make_shared<Texture>(ormTex, Texture::Type::ORM));

    // Add a visual model to render the surface of the tet mesh
    imstkNew<VisualModel> visualModel(surfMesh);
    visualModel->setRenderMaterial(material);
    clothObj->addVisualModel(visualModel);

    // Add a visual model to render the normals of the surface
    imstkNew<VisualModel> normalsVisualModel(surfMesh);
    normalsVisualModel->getRenderMaterial()->setDisplayMode(RenderMaterial::DisplayMode::SurfaceNormals);
    normalsVisualModel->getRenderMaterial()->setPointSize(0.5);
    clothObj->addVisualModel(normalsVisualModel);

    // Setup the Object
    clothObj->setPhysicsGeometry(tissueMesh);
    clothObj->setCollidingGeometry(surfMesh);
    clothObj->setPhysicsToCollidingMap(std::make_shared<OneToOneMap>(tissueMesh, surfMesh));
    clothObj->setDynamicalModel(pbdModel);

    return clothObj;
}

static std::shared_ptr<RigidObject2>
makeToolObj()
{
    imstkNew<LineMesh>                toolGeometry;
    imstkNew<VecDataArray<double, 3>> verticesPtr(2);
    (*verticesPtr)[0] = Vec3d(0.0, 0.0, 0.0);
    (*verticesPtr)[1] = Vec3d(0.0, 2.0, 0.0);
    imstkNew<VecDataArray<int, 2>> indicesPtr(1);
    (*indicesPtr)[0] = Vec2i(0, 1);
    toolGeometry->initialize(verticesPtr, indicesPtr);

    imstkNew<RigidObject2> toolObj("Tool");
    toolObj->setVisualGeometry(toolGeometry);
    toolObj->setCollidingGeometry(toolGeometry);
    toolObj->setPhysicsGeometry(toolGeometry);
    toolObj->getVisualModel(0)->getRenderMaterial()->setColor(Color::Blue);
    toolObj->getVisualModel(0)->getRenderMaterial()->setDisplayMode(RenderMaterial::DisplayMode::Wireframe);
    toolObj->getVisualModel(0)->getRenderMaterial()->setBackFaceCulling(false);
    toolObj->getVisualModel(0)->getRenderMaterial()->setLineWidth(10.0);

    std::shared_ptr<RigidBodyModel2> rbdModel = std::make_shared<RigidBodyModel2>();
    rbdModel->getConfig()->m_gravity = Vec3d::Zero();
    rbdModel->getConfig()->m_maxNumIterations       = 8;
    rbdModel->getConfig()->m_velocityDamping        = 1.0;
    rbdModel->getConfig()->m_angularVelocityDamping = 1.0;
    rbdModel->getConfig()->m_maxNumConstraints      = 40;
    toolObj->setDynamicalModel(rbdModel);

    toolObj->getRigidBody()->m_mass = 1.0;
    toolObj->getRigidBody()->m_intertiaTensor = Mat3d::Identity() * 10000.0;
#ifdef iMSTK_USE_OPENHAPTICS
    toolObj->getRigidBody()->m_initPos = Vec3d(0.0, 0.8, 0.0);
#else
    toolObj->getRigidBody()->m_initPos = Vec3d(0.0, 0.0, 0.0);
#endif

    return toolObj;
}

///
/// \brief This example demonstrates collision interaction with a 3d pbd
/// simulated tissue (tetrahedral)
///
int
main()
{
    // Setup logger (write to file and stdout)
    Logger::startLogger();

    // Setup the scene
    imstkNew<Scene> scene("PBDTissueContact");
    scene->getActiveCamera()->setPosition(0.12, 4.51, 16.51);
    scene->getActiveCamera()->setFocalPoint(0.0, 0.0, 0.0);
    scene->getActiveCamera()->setViewUp(0.0, 0.96, -0.28);
    scene->getConfig()->writeTaskGraph = true;

    // Setup a tissue
    std::shared_ptr<PbdObject> tissueObj = makeTissueObj("Tissue",
        Vec3d(8.0, 3.0, 8.0), Vec3i(8, 3, 8), Vec3d(0.0, -1.0, 0.0));
    scene->addSceneObject(tissueObj);

    std::shared_ptr<RigidObject2> toolObj = makeToolObj();
    scene->addSceneObject(toolObj);

#ifdef TWOWAY_COUPLING
    // With PbdRigidObjectCollision we have Pbd-Rigid coupling
    // The toolObj responds to the tissue (the tool is pushed partly out of the way of the tissue whilst the
    // tissue deforms)
    auto interaction = std::make_shared<PbdRigidObjectCollision>(tissueObj, toolObj, "MeshToMeshBruteForceCD");
    std::dynamic_pointer_cast<MeshToMeshBruteForceCD>(interaction->getCollisionDetection())->setGenerateEdgeEdgeContacts(true);
    scene->addInteraction(interaction);
#else
    // With PbdObjectCollision we only have one-way coupling
    // The toolObj does not respond to the tissue (only the tissueObj responds to the tool, moving out of the way)
    auto interaction = std::make_shared<PbdObjectCollision>(tissueObj, toolObj);
    std::dynamic_pointer_cast<MeshToMeshBruteForceCD>(interaction->getCollisionDetection())->setGenerateEdgeEdgeContacts(true);
    scene->addInteraction(interaction);
#endif

    // Light
    imstkNew<DirectionalLight> light;
    light->setFocalPoint(Vec3d(5.0, -8.0, -5.0));
    light->setIntensity(1);
    scene->addLight("Light", light);

    // Run the simulation
    {
        // Setup a viewer to render
        imstkNew<VTKViewer> viewer;
        viewer->setActiveScene(scene);
        viewer->setVtkLoggerMode(VTKViewer::VTKLoggerMode::MUTE);

        // Setup a scene manager to advance the scene
        imstkNew<SceneManager> sceneManager;
        sceneManager->setActiveScene(scene);
        sceneManager->pause(); // Start simulation paused

        imstkNew<SimulationManager> driver;
        driver->addModule(viewer);
        driver->addModule(sceneManager);
        driver->setDesiredDt(0.002);

#ifdef iMSTK_USE_OPENHAPTICS
        imstkNew<HapticDeviceManager> hapticManager;
        hapticManager->setSleepDelay(1.0); // Delay for 1ms (haptics thread is limited to max 1000hz)
        std::shared_ptr<HapticDeviceClient> hapticDeviceClient = hapticManager->makeDeviceClient();
        driver->addModule(hapticManager);

        imstkNew<RigidObjectController> controller(toolObj, hapticDeviceClient);
        controller->setTranslationScaling(0.05);
        controller->setLinearKs(5000.0);
        controller->setLinearKd(100.0);
        controller->setAngularKs(10000000.0);
        controller->setAngularKd(500000.0);
        controller->setForceScaling(0.0025);
        controller->setUseForceSmoothening(true);
        scene->addController(controller);
#else
        connect<Event>(sceneManager, &SceneManager::postUpdate, [&](Event*)
            {
                const Vec2d mousePos = viewer->getMouseDevice()->getPos();
                const Vec3d worldPos = Vec3d(mousePos[0] - 0.5, mousePos[1] - 0.5, 0.0) * 10.0;

                const Vec3d fS = (worldPos - toolObj->getRigidBody()->getPosition()) * 1000.0; // Spring force
                const Vec3d fD = -toolObj->getRigidBody()->getVelocity() * 100.0;              // Spring damping

                (*toolObj->getRigidBody()->m_force) += (fS + fD);
            });
#endif

        // Toggle collision interaction in scene with key y
        connect<KeyEvent>(viewer->getKeyboardDevice(), &KeyboardDeviceClient::keyPress,
            [&](KeyEvent* e)
            {
                if (e->m_key == 'y')
                {
                    if (scene->getSceneObject(interaction->getName()) != nullptr)
                    {
                        scene->removeSceneObject(interaction);
                    }
                    else
                    {
                        scene->addInteraction(interaction);
                    }
                    scene->buildTaskGraph();
                    scene->initTaskGraph();
                }
            });

        connect<Event>(sceneManager, &SceneManager::postUpdate, [&](Event*)
            {
                // Keep the tool moving in real time
                toolObj->getRigidBodyModel2()->getConfig()->m_dt = sceneManager->getDt();
        });

        // Add mouse and keyboard controls to the viewer
        {
            imstkNew<MouseSceneControl> mouseControl(viewer->getMouseDevice());
            mouseControl->setSceneManager(sceneManager);
            viewer->addControl(mouseControl);

            imstkNew<KeyboardSceneControl> keyControl(viewer->getKeyboardDevice());
            keyControl->setSceneManager(sceneManager);
            keyControl->setModuleDriver(driver);
            viewer->addControl(keyControl);
        }

        driver->start();
    }

    return 0;
}