#include "libslic3r/libslic3r.h"

#include "3DBed.hpp"

#include "libslic3r/Polygon.hpp"
#include "libslic3r/ClipperUtils.hpp"
#include "libslic3r/BoundingBox.hpp"
#include "libslic3r/Geometry/Circle.hpp"
#include "libslic3r/Tesselate.hpp"
#include "libslic3r/PresetBundle.hpp"

#include "GUI_App.hpp"
#include "GLCanvas3D.hpp"
#include "Plater.hpp"
#include "Camera.hpp"

#include <GL/glew.h>

#include <boost/algorithm/string/predicate.hpp>
#include <boost/filesystem/operations.hpp>
#include <boost/log/trivial.hpp>

static const float GROUND_Z = -0.02f;
static const Slic3r::ColorRGBA DEFAULT_MODEL_COLOR             = Slic3r::ColorRGBA::DARK_GRAY();
static const Slic3r::ColorRGBA PICKING_MODEL_COLOR             = Slic3r::ColorRGBA::BLACK();
static const Slic3r::ColorRGBA DEFAULT_SOLID_GRID_COLOR        = { 0.9f, 0.9f, 0.9f, 1.0f };
static const Slic3r::ColorRGBA DEFAULT_TRANSPARENT_GRID_COLOR  = { 0.9f, 0.9f, 0.9f, 0.6f };

namespace Slic3r {
namespace GUI {

bool Bed3D::set_shape(const Pointfs& bed_shape, const double max_print_height, const std::string& custom_texture, const std::string& custom_model, bool force_as_custom)
{
    auto check_texture = [](const std::string& texture) {
        boost::system::error_code ec; // so the exists call does not throw (e.g. after a permission problem)
        return !texture.empty() && (boost::algorithm::iends_with(texture, ".png") || boost::algorithm::iends_with(texture, ".svg")) && boost::filesystem::exists(texture, ec);
    };

    auto check_model = [](const std::string& model) {
        boost::system::error_code ec;
        return !model.empty() && boost::algorithm::iends_with(model, ".stl") && boost::filesystem::exists(model, ec);
    };

    Type type;
    std::string model;
    std::string texture;
    if (force_as_custom)
        type = Type::Custom;
    else {
        auto [new_type, system_model, system_texture] = detect_type(bed_shape);
        type = new_type;
        model = system_model;
        texture = system_texture;
    }

    std::string texture_filename = custom_texture.empty() ? texture : custom_texture;
    if (! texture_filename.empty() && ! check_texture(texture_filename)) {
        BOOST_LOG_TRIVIAL(error) << "Unable to load bed texture: " << texture_filename;
        texture_filename.clear();
    }

    std::string model_filename = custom_model.empty() ? model : custom_model;
    if (! model_filename.empty() && ! check_model(model_filename)) {
        BOOST_LOG_TRIVIAL(error) << "Unable to load bed model: " << model_filename;
        model_filename.clear();
    }

    
    if (m_build_volume.bed_shape() == bed_shape && m_build_volume.max_print_height() == max_print_height && m_type == type && m_texture_filename == texture_filename && m_model_filename == model_filename)
        // No change, no need to update the UI.
        return false;

    m_type = type;
    m_build_volume = BuildVolume { bed_shape, max_print_height };
    m_texture_filename = texture_filename;
    m_model_filename = model_filename;
    m_extended_bounding_box = this->calc_extended_bounding_box();

    m_contour = ExPolygon(Polygon::new_scale(bed_shape));
    const BoundingBox bbox = m_contour.contour.bounding_box();
    if (!bbox.defined)
        throw RuntimeError(std::string("Invalid bed shape"));
    m_polygon = offset(m_contour.contour, (float)bbox.radius() * 1.7f, jtRound, scale_(0.5)).front();

    m_triangles.reset();
    m_gridlines.reset();
    m_contourlines.reset();
    m_texture.reset();
    m_model.reset();

    // Set the origin and size for rendering the coordinate system axes.
    m_axes.set_origin({ 0.0, 0.0, static_cast<double>(GROUND_Z) });
    m_axes.set_stem_length(0.1f * static_cast<float>(m_build_volume.bounding_volume().max_size()));

    // unregister from picking
    wxGetApp().plater()->canvas3D()->remove_raycasters_for_picking(SceneRaycaster::EType::Bed);

    // Let the calee to update the UI.
    return true;
}

bool Bed3D::contains(const Point& point) const
{
    return m_polygon.contains(point);
}

Point Bed3D::point_projection(const Point& point) const
{
    return m_polygon.point_projection(point);
}

void Bed3D::render(GLCanvas3D& canvas, const Transform3d& view_matrix, const Transform3d& projection_matrix, bool bottom, float scale_factor, bool show_texture)
{
    render_internal(canvas, view_matrix, projection_matrix, bottom, scale_factor, show_texture, false);
}

void Bed3D::render_for_picking(GLCanvas3D& canvas, const Transform3d& view_matrix, const Transform3d& projection_matrix, bool bottom, float scale_factor)
{
    render_internal(canvas, view_matrix, projection_matrix, bottom, scale_factor, false, true);
}

void Bed3D::render_internal(GLCanvas3D& canvas, const Transform3d& view_matrix, const Transform3d& projection_matrix, bool bottom, float scale_factor,
    bool show_texture, bool picking)
{
    m_scale_factor = scale_factor;

    glsafe(::glEnable(GL_DEPTH_TEST));

    m_model.model.set_color(picking ? PICKING_MODEL_COLOR : DEFAULT_MODEL_COLOR);

    switch (m_type)
    {
    case Type::System: { render_system(canvas, view_matrix, projection_matrix, bottom, show_texture); break; }
    default:
    case Type::Custom: { render_custom(canvas, view_matrix, projection_matrix, bottom, show_texture, picking); break; }
    }

    glsafe(::glDisable(GL_DEPTH_TEST));
}

// Calculate an extended bounding box from axes and current model for visualization purposes.
BoundingBoxf3 Bed3D::calc_extended_bounding_box() const
{
    BoundingBoxf3 out { m_build_volume.bounding_volume() };
    const Vec3d size = out.size();
    // ensures that the bounding box is set as defined or the following calls to merge() will not work as intented
    if (size.x() > 0.0 && size.y() > 0.0 && !out.defined)
        out.defined = true;
    // Reset the build volume Z, we don't want to zoom to the top of the build volume if it is empty.
    out.min.z() = 0.0;
    out.max.z() = 0.0;
    // extend to origin in case origin is off bed
    out.merge(m_axes.get_origin());
    // extend to contain axes
    out.merge(m_axes.get_origin() + m_axes.get_total_length() * Vec3d::Ones());
    out.merge(out.min + Vec3d(-m_axes.get_tip_radius(), -m_axes.get_tip_radius(), out.max.z()));
    // extend to contain model, if any
    BoundingBoxf3 model_bb = m_model.model.get_bounding_box();
    if (model_bb.defined) {
        model_bb.translate(m_model_offset);
        out.merge(model_bb);
    }
    return out;
}

void Bed3D::init_triangles()
{
    if (m_triangles.is_initialized())
        return;

    if (m_contour.empty())
        return;

    const std::vector<Vec2f> triangles = triangulate_expolygon_2f(m_contour, NORMALS_UP);
    if (triangles.empty() || triangles.size() % 3 != 0)
        return;

    GLModel::Geometry init_data;
    init_data.format = { GLModel::Geometry::EPrimitiveType::Triangles, GLModel::Geometry::EVertexLayout::P3T2 };
    init_data.reserve_vertices(triangles.size());
    init_data.reserve_indices(triangles.size() / 3);

    Vec2f min = triangles.front();
    Vec2f max = min;
    for (const Vec2f& v : triangles) {
        min = min.cwiseMin(v).eval();
        max = max.cwiseMax(v).eval();
    }

    const Vec2f size = max - min;
    if (size.x() <= 0.0f || size.y() <= 0.0f)
        return;

    Vec2f inv_size = size.cwiseInverse();
    inv_size.y() *= -1.0f;

    // vertices + indices
    unsigned int vertices_counter = 0;
    for (const Vec2f& v : triangles) {
        const Vec3f p = { v.x(), v.y(), GROUND_Z };
        init_data.add_vertex(p, (Vec2f)(v - min).cwiseProduct(inv_size).eval());
        ++vertices_counter;
        if (vertices_counter % 3 == 0)
            init_data.add_triangle(vertices_counter - 3, vertices_counter - 2, vertices_counter - 1);
    }

    if (m_model.model.get_filename().empty() && m_model.mesh_raycaster == nullptr)
        // register for picking
        register_raycasters_for_picking(init_data, Transform3d::Identity());

    m_triangles.init_from(std::move(init_data));
    m_triangles.set_color(DEFAULT_MODEL_COLOR);
}

void Bed3D::init_gridlines()
{
    if (m_gridlines.is_initialized())
        return;

    if (m_contour.empty())
        return;

    const BoundingBox& bed_bbox = m_contour.contour.bounding_box();
    const coord_t step = scale_(10.0);

    Polylines axes_lines;
    for (coord_t x = bed_bbox.min.x(); x <= bed_bbox.max.x(); x += step) {
        Polyline line;
        line.append(Point(x, bed_bbox.min.y()));
        line.append(Point(x, bed_bbox.max.y()));
        axes_lines.push_back(line);
    }
    for (coord_t y = bed_bbox.min.y(); y <= bed_bbox.max.y(); y += step) {
        Polyline line;
        line.append(Point(bed_bbox.min.x(), y));
        line.append(Point(bed_bbox.max.x(), y));
        axes_lines.push_back(line);
    }

    // clip with a slightly grown expolygon because our lines lay on the contours and may get erroneously clipped
    Lines gridlines = to_lines(intersection_pl(axes_lines, offset(m_contour, float(SCALED_EPSILON))));

    // append bed contours
    Lines contour_lines = to_lines(m_contour);
    std::copy(contour_lines.begin(), contour_lines.end(), std::back_inserter(gridlines));

    GLModel::Geometry init_data;
    init_data.format = { GLModel::Geometry::EPrimitiveType::Lines, GLModel::Geometry::EVertexLayout::P3 };
    init_data.reserve_vertices(2 * gridlines.size());
    init_data.reserve_indices(2 * gridlines.size());

    for (const Slic3r::Line& l : gridlines) {
        init_data.add_vertex(Vec3f(unscale<float>(l.a.x()), unscale<float>(l.a.y()), GROUND_Z));
        init_data.add_vertex(Vec3f(unscale<float>(l.b.x()), unscale<float>(l.b.y()), GROUND_Z));
        const unsigned int vertices_counter = (unsigned int)init_data.vertices_count();
        init_data.add_line(vertices_counter - 2, vertices_counter - 1);
    }

    m_gridlines.init_from(std::move(init_data));
}

void Bed3D::init_contourlines()
{
    if (m_contourlines.is_initialized())
        return;

    if (m_contour.empty())
        return;

    const Lines contour_lines = to_lines(m_contour);

    GLModel::Geometry init_data;
    init_data.format = { GLModel::Geometry::EPrimitiveType::Lines, GLModel::Geometry::EVertexLayout::P3 };
    init_data.reserve_vertices(2 * contour_lines.size());
    init_data.reserve_indices(2 * contour_lines.size());

    for (const Slic3r::Line& l : contour_lines) {
        init_data.add_vertex(Vec3f(unscale<float>(l.a.x()), unscale<float>(l.a.y()), GROUND_Z));
        init_data.add_vertex(Vec3f(unscale<float>(l.b.x()), unscale<float>(l.b.y()), GROUND_Z));
        const unsigned int vertices_counter = (unsigned int)init_data.vertices_count();
        init_data.add_line(vertices_counter - 2, vertices_counter - 1);
    }

    m_contourlines.init_from(std::move(init_data));
    m_contourlines.set_color({ 1.0f, 1.0f, 1.0f, 0.5f });
}

// Try to match the print bed shape with the shape of an active profile. If such a match exists,
// return the print bed model.
std::tuple<Bed3D::Type, std::string, std::string> Bed3D::detect_type(const Pointfs& shape)
{
    auto bundle = wxGetApp().preset_bundle;
    if (bundle != nullptr) {
        const Preset* curr = &bundle->printers.get_selected_preset();
        while (curr != nullptr) {
            if (curr->config.has("bed_shape")) {
                if (shape == dynamic_cast<const ConfigOptionPoints*>(curr->config.option("bed_shape"))->values) {
                    std::string model_filename = PresetUtils::system_printer_bed_model(*curr);
                    std::string texture_filename = PresetUtils::system_printer_bed_texture(*curr);
                    if (!model_filename.empty() && !texture_filename.empty())
                        return { Type::System, model_filename, texture_filename };
                }
            }

            curr = bundle->printers.get_preset_parent(*curr);
        }
    }

    return { Type::Custom, {}, {} };
}

void Bed3D::render_axes()
{
    if (m_build_volume.valid())
        m_axes.render(Transform3d::Identity(), 0.25f);
}

void Bed3D::render_system(GLCanvas3D& canvas, const Transform3d& view_matrix, const Transform3d& projection_matrix, bool bottom, bool show_texture)
{
    if (!bottom)
        render_model(view_matrix, projection_matrix);

    if (show_texture)
        render_texture(bottom, canvas, view_matrix, projection_matrix);
    else if (bottom)
        render_contour(view_matrix, projection_matrix);
}

void Bed3D::render_texture(bool bottom, GLCanvas3D& canvas, const Transform3d& view_matrix, const Transform3d& projection_matrix)
{
    if (m_texture_filename.empty()) {
        m_texture.reset();
        render_default(bottom, false, true, view_matrix, projection_matrix);
        return;
    }

    if (m_texture.get_id() == 0 || m_texture.get_source() != m_texture_filename) {
        m_texture.reset();

        if (boost::algorithm::iends_with(m_texture_filename, ".svg")) {
            // use higher resolution images if graphic card and opengl version allow
            GLint max_tex_size = OpenGLManager::get_gl_info().get_max_tex_size();
            if (m_temp_texture.get_id() == 0 || m_temp_texture.get_source() != m_texture_filename) {
                // generate a temporary lower resolution texture to show while no main texture levels have been compressed
                if (!m_temp_texture.load_from_svg_file(m_texture_filename, false, false, false, max_tex_size / 8)) {
                    render_default(bottom, false, true, view_matrix, projection_matrix);
                    return;
                }
                canvas.request_extra_frame();
            }

            // starts generating the main texture, compression will run asynchronously
            if (!m_texture.load_from_svg_file(m_texture_filename, true, true, true, max_tex_size)) {
                render_default(bottom, false, true, view_matrix, projection_matrix);
                return;
            }
        } 
        else if (boost::algorithm::iends_with(m_texture_filename, ".png")) {
            // generate a temporary lower resolution texture to show while no main texture levels have been compressed
            if (m_temp_texture.get_id() == 0 || m_temp_texture.get_source() != m_texture_filename) {
                if (!m_temp_texture.load_from_file(m_texture_filename, false, GLTexture::None, false)) {
                    render_default(bottom, false, true, view_matrix, projection_matrix);
                    return;
                }
                canvas.request_extra_frame();
            }

            // starts generating the main texture, compression will run asynchronously
            if (!m_texture.load_from_file(m_texture_filename, true, GLTexture::MultiThreaded, true)) {
                render_default(bottom, false, true, view_matrix, projection_matrix);
                return;
            }
        }
        else {
            render_default(bottom, false, true, view_matrix, projection_matrix);
            return;
        }
    }
    else if (m_texture.unsent_compressed_data_available()) {
        // sends to gpu the already available compressed levels of the main texture
        m_texture.send_compressed_data_to_gpu();

        // the temporary texture is not needed anymore, reset it
        if (m_temp_texture.get_id() != 0)
            m_temp_texture.reset();

        canvas.request_extra_frame();
    }

    init_triangles();

    GLShaderProgram* shader = wxGetApp().get_shader("printbed");
    if (shader != nullptr) {
        shader->start_using();
        shader->set_uniform("view_model_matrix", view_matrix);
        shader->set_uniform("projection_matrix", projection_matrix);
        shader->set_uniform("transparent_background", bottom);
        shader->set_uniform("svg_source", boost::algorithm::iends_with(m_texture.get_source(), ".svg"));

        glsafe(::glEnable(GL_DEPTH_TEST));
        if (bottom)
            glsafe(::glDepthMask(GL_FALSE));

        glsafe(::glEnable(GL_BLEND));
        glsafe(::glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA));

        if (bottom)
            glsafe(::glFrontFace(GL_CW));

        // show the temporary texture while no compressed data is available
        GLuint tex_id = (GLuint)m_temp_texture.get_id();
        if (tex_id == 0)
            tex_id = (GLuint)m_texture.get_id();

        glsafe(::glBindTexture(GL_TEXTURE_2D, tex_id));
        m_triangles.render();
        glsafe(::glBindTexture(GL_TEXTURE_2D, 0));

        if (bottom)
            glsafe(::glFrontFace(GL_CCW));

        glsafe(::glDisable(GL_BLEND));
        if (bottom)
            glsafe(::glDepthMask(GL_TRUE));

        shader->stop_using();
    }
}

void Bed3D::render_model(const Transform3d& view_matrix, const Transform3d& projection_matrix)
{
    if (m_model_filename.empty())
        return;

    if (m_model.model.get_filename() != m_model_filename && m_model.model.init_from_file(m_model_filename)) {
        m_model.model.set_color(DEFAULT_MODEL_COLOR);

        // move the model so that its origin (0.0, 0.0, 0.0) goes into the bed shape center and a bit down to avoid z-fighting with the texture quad
        m_model_offset = to_3d(m_build_volume.bounding_volume2d().center(), -0.03);

        // register for picking
        const std::vector<std::shared_ptr<SceneRaycasterItem>>* const raycaster = wxGetApp().plater()->canvas3D()->get_raycasters_for_picking(SceneRaycaster::EType::Bed);
        if (!raycaster->empty()) {
            // The raycaster may have been set by the call to init_triangles() made from render_texture() if the printbed was
            // changed while the camera was pointing upward.
            // In this case we need to remove it before creating a new using the model geometry
            wxGetApp().plater()->canvas3D()->remove_raycasters_for_picking(SceneRaycaster::EType::Bed);
            m_model.mesh_raycaster.reset();
        }
        register_raycasters_for_picking(m_model.model.get_geometry(), Geometry::translation_transform(m_model_offset));

        // update extended bounding box
        m_extended_bounding_box = this->calc_extended_bounding_box();
    }

    if (!m_model.model.get_filename().empty()) {
        GLShaderProgram* shader = wxGetApp().get_shader("gouraud_light");
        if (shader != nullptr) {
            shader->start_using();
            shader->set_uniform("emission_factor", 0.0f);
            const Transform3d model_matrix = Geometry::translation_transform(m_model_offset);
            shader->set_uniform("view_model_matrix", view_matrix * model_matrix);
            shader->set_uniform("projection_matrix", projection_matrix);
            const Matrix3d view_normal_matrix = view_matrix.matrix().block(0, 0, 3, 3) * model_matrix.matrix().block(0, 0, 3, 3).inverse().transpose();
            shader->set_uniform("view_normal_matrix", view_normal_matrix);
            m_model.model.render();
            shader->stop_using();
        }
    }
}

void Bed3D::render_custom(GLCanvas3D& canvas, const Transform3d& view_matrix, const Transform3d& projection_matrix, bool bottom, bool show_texture, bool picking)
{
    if (m_texture_filename.empty() && m_model_filename.empty()) {
        render_default(bottom, picking, show_texture, view_matrix, projection_matrix);
        return;
    }

    if (!bottom)
        render_model(view_matrix, projection_matrix);

    if (show_texture)
        render_texture(bottom, canvas, view_matrix, projection_matrix);
    else if (bottom)
        render_contour(view_matrix, projection_matrix);
}

void Bed3D::render_default(bool bottom, bool picking, bool show_texture, const Transform3d& view_matrix, const Transform3d& projection_matrix)
{
    m_texture.reset();

    init_gridlines();
    init_triangles();

    GLShaderProgram* shader = wxGetApp().get_shader("flat");
    if (shader != nullptr) {
        shader->start_using();

        shader->set_uniform("view_model_matrix", view_matrix);
        shader->set_uniform("projection_matrix", projection_matrix);

        glsafe(::glEnable(GL_DEPTH_TEST));
        glsafe(::glEnable(GL_BLEND));
        glsafe(::glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA));

        const bool has_model = !m_model.model.get_filename().empty();
        if (!has_model && !bottom) {
            // draw background
            glsafe(::glDepthMask(GL_FALSE));
            m_triangles.render();
            glsafe(::glDepthMask(GL_TRUE));
        }

        if (show_texture) {
            // draw grid
#if ENABLE_GL_CORE_PROFILE
            if (!OpenGLManager::get_gl_info().is_core_profile())
#endif // ENABLE_GL_CORE_PROFILE
                glsafe(::glLineWidth(1.5f * m_scale_factor));
            m_gridlines.set_color(has_model && !bottom ? DEFAULT_SOLID_GRID_COLOR : DEFAULT_TRANSPARENT_GRID_COLOR);
            m_gridlines.render();
        }
        else
            render_contour(view_matrix, projection_matrix);

        glsafe(::glDisable(GL_BLEND));

        shader->stop_using();
    }
}

void Bed3D::render_contour(const Transform3d& view_matrix, const Transform3d& projection_matrix)
{
    init_contourlines();

    GLShaderProgram* shader = wxGetApp().get_shader("flat");
    if (shader != nullptr) {
        shader->start_using();
        shader->set_uniform("view_model_matrix", view_matrix);
        shader->set_uniform("projection_matrix", projection_matrix);

        glsafe(::glEnable(GL_DEPTH_TEST));
        glsafe(::glEnable(GL_BLEND));
        glsafe(::glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA));

        // draw contour
#if ENABLE_GL_CORE_PROFILE
        if (!OpenGLManager::get_gl_info().is_core_profile())
#endif // ENABLE_GL_CORE_PROFILE
            glsafe(::glLineWidth(1.5f * m_scale_factor));
        m_contourlines.render();

        glsafe(::glDisable(GL_BLEND));

        shader->stop_using();
    }
}

void Bed3D::register_raycasters_for_picking(const GLModel::Geometry& geometry, const Transform3d& trafo)
{
    assert(m_model.mesh_raycaster == nullptr);

    indexed_triangle_set its;
    its.vertices.reserve(geometry.vertices_count());
    for (size_t i = 0; i < geometry.vertices_count(); ++i) {
        its.vertices.emplace_back(geometry.extract_position_3(i));
    }
    its.indices.reserve(geometry.indices_count() / 3);
    for (size_t i = 0; i < geometry.indices_count() / 3; ++i) {
        const size_t tri_id = i * 3;
        its.indices.emplace_back(geometry.extract_index(tri_id), geometry.extract_index(tri_id + 1), geometry.extract_index(tri_id + 2));
    }

    m_model.mesh_raycaster = std::make_unique<MeshRaycaster>(std::make_shared<const TriangleMesh>(std::move(its)));
    wxGetApp().plater()->canvas3D()->add_raycaster_for_picking(SceneRaycaster::EType::Bed, 0, *m_model.mesh_raycaster, trafo);
}

} // GUI
} // Slic3r
