#include <hex/api/content_registry.hpp>
#include <hex/api/localization.hpp>

#include <hex/helpers/disassembler.hpp>
#include <hex/helpers/utils.hpp>
#include <hex/helpers/opengl.hpp>

#include <imgui.h>
#include <implot.h>
#include <imgui_impl_opengl3_loader.h>
#include <hex/ui/imgui_imhex_extensions.h>

#include <pl/patterns/pattern.hpp>

#include <romfs/romfs.hpp>

#include <numeric>

namespace hex::plugin::builtin {

    namespace {

        void drawLinePlotVisualizer(pl::ptrn::Pattern &, pl::ptrn::Iteratable &iteratable, bool, const std::vector<pl::core::Token::Literal> &) {
            if (ImPlot::BeginPlot("##plot", ImVec2(400, 250), ImPlotFlags_NoChild | ImPlotFlags_CanvasOnly)) {

                ImPlot::SetupAxes("X", "Y", ImPlotAxisFlags_AutoFit, ImPlotAxisFlags_AutoFit);

                ImPlot::PlotLineG("##line", [](void *data, int idx) -> ImPlotPoint {
                    auto &iteratable = *static_cast<pl::ptrn::Iteratable *>(data);
                    return { static_cast<double>(idx), iteratable.getEntry(idx)->getValue().toFloatingPoint() };
                }, &iteratable, iteratable.getEntryCount());

                ImPlot::EndPlot();
            }
        }

        void drawImageVisualizer(pl::ptrn::Pattern &pattern, pl::ptrn::Iteratable &, bool shouldReset, const std::vector<pl::core::Token::Literal> &) {
            static ImGui::Texture texture;
            if (shouldReset) {
                std::vector<u8> data;
                data.resize(pattern.getSize());
                pattern.getEvaluator()->readData(pattern.getOffset(), data.data(), data.size(), pattern.getSection());
                texture = ImGui::Texture(data.data(), data.size());
            }

            if (texture.isValid())
                ImGui::Image(texture, texture.getSize());
        }

        void drawBitmapVisualizer(pl::ptrn::Pattern &pattern, pl::ptrn::Iteratable &, bool shouldReset, const std::vector<pl::core::Token::Literal> &arguments) {
            static ImGui::Texture texture;
            if (shouldReset) {
                auto width  = arguments[1].toUnsigned();
                auto height = arguments[2].toUnsigned();

                std::vector<u8> data;
                data.resize(width * height * 4);

                pattern.getEvaluator()->readData(pattern.getOffset(), data.data(), data.size(), pattern.getSection());
                texture = ImGui::Texture(data.data(), data.size(), width, height);
            }

            if (texture.isValid())
                ImGui::Image(texture, texture.getSize());
        }

        void drawDisassemblyVisualizer(pl::ptrn::Pattern &pattern, pl::ptrn::Iteratable &, bool shouldReset, const std::vector<pl::core::Token::Literal> &arguments) {
            struct Disassembly {
                u64 address;
                std::vector<u8> bytes;
                std::string instruction;
            };

            static std::vector<Disassembly> disassembly;
            if (shouldReset) {
                auto baseAddress  = arguments[1].toUnsigned();
                auto architecture = arguments[2].toUnsigned();
                auto mode         = arguments[3].toUnsigned();

                disassembly.clear();

                csh capstone;
                if (cs_open(static_cast<cs_arch>(architecture), static_cast<cs_mode>(mode), &capstone) == CS_ERR_OK) {
                    cs_option(capstone, CS_OPT_SKIPDATA, CS_OPT_ON);

                    std::vector<u8> data;
                    data.resize(pattern.getSize());
                    pattern.getEvaluator()->readData(pattern.getOffset(), data.data(), data.size(), pattern.getSection());
                    cs_insn *instructions = nullptr;

                    size_t instructionCount = cs_disasm(capstone, data.data(), data.size(), baseAddress, 0, &instructions);
                    for (size_t i = 0; i < instructionCount; i++) {
                        disassembly.push_back({ instructions[i].address, { instructions[i].bytes, instructions[i].bytes + instructions[i].size }, hex::format("{} {}", instructions[i].mnemonic, instructions[i].op_str) });
                    }
                    cs_free(instructions, instructionCount);
                    cs_close(&capstone);
                }
            }

            if (ImGui::BeginTable("##disassembly", 3, ImGuiTableFlags_Borders | ImGuiTableFlags_RowBg | ImGuiTableFlags_Resizable | ImGuiTableFlags_Reorderable | ImGuiTableFlags_SizingFixedFit | ImGuiTableFlags_ScrollY, scaled(ImVec2(0, 300)))) {
                ImGui::TableSetupScrollFreeze(0, 1);
                ImGui::TableSetupColumn("hex.builtin.common.address"_lang);
                ImGui::TableSetupColumn("hex.builtin.common.bytes"_lang);
                ImGui::TableSetupColumn("hex.builtin.common.instruction"_lang);
                ImGui::TableHeadersRow();

                for (auto &entry : disassembly) {
                    ImGui::TableNextRow();
                    ImGui::TableNextColumn();
                    ImGui::TextFormatted("0x{0:08X}", entry.address);
                    ImGui::TableNextColumn();
                    std::string bytes;
                    for (auto byte : entry.bytes)
                        bytes += hex::format("{0:02X} ", byte);
                    ImGui::TextUnformatted(bytes.c_str());
                    ImGui::TableNextColumn();
                    ImGui::TextUnformatted(entry.instruction.c_str());
                }

                ImGui::EndTable();
            }
        }

        template<typename T>
        static auto readValues(pl::ptrn::Pattern *pattern){
            std::vector<T> result;

            if (pattern->getSize() == 0)
                return result;

            if (auto iteratable = dynamic_cast<pl::ptrn::Iteratable*>(pattern); iteratable != nullptr) {
                result.reserve(iteratable->getEntryCount());
                iteratable->forEachEntry(0, iteratable->getEntryCount(), [&](u64, pl::ptrn::Pattern *entry) {
                    for (auto [offset, child] : entry->getChildren()) {
                        child->setOffset(offset);

                        T value;
                        if (std::floating_point<T>)
                            value = child->getValue().toFloatingPoint();
                        else
                            value = child->getValue().toUnsigned();

                        result.push_back(value);
                    }
                });
            } else {
                result.reserve(pattern->getSize() / sizeof(float));
                pattern->getEvaluator()->readData(pattern->getOffset(), result.data(), result.size() * sizeof(float), pattern->getSection());
            }

            return result;
        };

        void draw3DVisualizer(pl::ptrn::Pattern &, pl::ptrn::Iteratable &, bool shouldReset, const std::vector<pl::core::Token::Literal> &arguments) {
            auto verticesPattern = arguments[1].toPattern();
            auto indicesPattern  = arguments[2].toPattern();

            static ImGui::Texture texture;
            static float scaling = 0.5F;
            static gl::Vector<float, 3> rotation = { { 1.0F, -1.0F, 0.0F } };
            static std::vector<float> vertices, normals;
            static std::vector<u32> indices;
            static gl::Shader shader;
            static gl::VertexArray vertexArray;
            static gl::Buffer<float> vertexBuffer, normalBuffer;
            static gl::Buffer<u32> indexBuffer;

            {
                auto dragDelta = ImGui::GetMouseDragDelta(ImGuiMouseButton_Middle);
                rotation[0] += -dragDelta.y * 0.0075F;
                rotation[1] += -dragDelta.x * 0.0075F;
                ImGui::ResetMouseDragDelta(ImGuiMouseButton_Middle);

                auto scrollDelta = ImGui::GetIO().MouseWheel;
                scaling += scrollDelta * 0.01F;

                if (scaling < 0.01F)
                    scaling = 0.01F;
            }

            if (shouldReset) {
                vertices = readValues<float>(verticesPattern);
                indices = readValues<u32>(indicesPattern);

                normals.clear();
                normals.resize(vertices.size());
                for (u32 i = 0; i < normals.size() && normals.size() >= 9; i += 9) {
                    auto v1 = gl::Vector<float, 3>({ vertices[i + 0], vertices[i + 1], vertices[i + 2] });
                    auto v2 = gl::Vector<float, 3>({ vertices[i + 3], vertices[i + 4], vertices[i + 5] });
                    auto v3 = gl::Vector<float, 3>({ vertices[i + 6], vertices[i + 7], vertices[i + 8] });

                    auto normal = ((v2 - v1).cross(v3 - v1)).normalize();
                    normals[i + 0] = normal[0];
                    normals[i + 1] = normal[1];
                    normals[i + 2] = normal[2];
                    normals[i + 3] = normal[0];
                    normals[i + 4] = normal[1];
                    normals[i + 5] = normal[2];
                    normals[i + 6] = normal[0];
                    normals[i + 7] = normal[1];
                    normals[i + 8] = normal[2];
                }

                shader = gl::Shader(romfs::get("shaders/default/vertex.glsl").string(), romfs::get("shaders/default/fragment.glsl").string());

                vertexArray = gl::VertexArray();
                vertexArray.bind();

                vertexBuffer = gl::Buffer<float> (gl::BufferType::Vertex, vertices);
                normalBuffer = gl::Buffer<float>(gl::BufferType::Vertex, normals);
                indexBuffer = gl::Buffer<u32>(gl::BufferType::Index, indices);

                vertexArray.addBuffer(0, vertexBuffer);
                vertexArray.addBuffer(1, normalBuffer);

                if (!indices.empty())
                    vertexArray.addBuffer(2, indexBuffer);

                vertexBuffer.unbind();
                vertexArray.unbind();
            }

            {
                gl::FrameBuffer frameBuffer;

                gl::Texture renderTexture(512, 512);
                frameBuffer.attachTexture(renderTexture);

                frameBuffer.bind();

                glEnable(GL_DEPTH_TEST);

                shader.bind();
                shader.setUniform("scale", scaling);
                shader.setUniform("rotation", rotation);

                vertexArray.bind();

                glViewport(0, 0, renderTexture.getWidth(), renderTexture.getHeight());
                glClearColor(0.00F, 0.00F, 0.00F, 0.00f);
                glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

                if (indices.empty())
                    vertexBuffer.draw();
                else
                    indexBuffer.draw();

                vertexArray.unbind();
                shader.unbind();
                frameBuffer.unbind();

                texture = ImGui::Texture(renderTexture.release(), renderTexture.getWidth(), renderTexture.getHeight());
            }

            ImGui::Image(texture, texture.getSize(), ImVec2(0, 1), ImVec2(1, 0));
        }

    }

    void registerPatternLanguageVisualizers() {
        ContentRegistry::PatternLanguage::addVisualizer("line_plot", drawLinePlotVisualizer, 0);
        ContentRegistry::PatternLanguage::addVisualizer("image", drawImageVisualizer, 0);
        ContentRegistry::PatternLanguage::addVisualizer("bitmap", drawBitmapVisualizer, 3);
        ContentRegistry::PatternLanguage::addVisualizer("disassembler", drawDisassemblyVisualizer, 4);
        ContentRegistry::PatternLanguage::addVisualizer("3d", draw3DVisualizer, 2);
    }

}