#include <signal.h>
#include <filesystem>
#include "imgui/imgui.h"
#include "imgui/imgui_impl_glfw.h"
#include "imgui/imgui_impl_opengl3.h"
#include "gl.h"
#include "logger.h"
#include "core/style.h"
#include "init.h"
#include "processing.h"
#include "main_ui.h"
#include "satdump_vars.h"
#include "loading_screen.h"
#include "common/cli_utils.h"
#include "../src-core/resources.h"

static volatile bool signal_caught = false;
bool fallback_gl = false;

void sig_handler_ui(int signo)
{
    if (signo == SIGINT || signo == SIGTERM)
        signal_caught = true;
}

static void glfw_error_callback(int error, const char *description)
{
    logger->error("Glfw Error " + std::to_string(error) + ": " + description);
}

void window_content_scale_callback(GLFWwindow *, float xscale, float)
{
    satdump::updateUI(xscale / style::macos_framebuffer_scale());
    style::setFonts();
#ifndef IMGUI_IMPL_OPENGL_ES2
    if (fallback_gl)
    {
        ImGui_ImplOpenGL2_DestroyFontsTexture();
        ImGui_ImplOpenGL2_CreateFontsTexture();
    }
    else
#endif
    {
        ImGui_ImplOpenGL3_DestroyFontsTexture();
        ImGui_ImplOpenGL3_CreateFontsTexture();
    }
}

void bindBaseTextureFunctions();
void bindAdvancedTextureFunctions();

int main(int argc, char *argv[])
{
    initLogger();

    if (argc < 5) // Check overall command
    {
        logger->error("Usage : " + std::string(argv[0]) + " [downlink] [input_level] [input_file] [output_file_or_directory] [additional options as required]");
        logger->error("Extra options (examples. Any parameter used in modules can be used here) :");
        logger->error(" --samplerate [baseband_samplerate] --baseband_format [f32/i16/i8/w8] --dc_block --iq_swap");
    }
    else
        satdump::processing::is_processing = true;

    std::string downlink_pipeline = satdump::processing::is_processing ? argv[1] : "";
    std::string input_level = satdump::processing::is_processing ? argv[2] : "";
    std::string input_file = satdump::processing::is_processing ? argv[3] : "";
    std::string output_file = satdump::processing::is_processing ? argv[4] : "";

    // Parse flags
    nlohmann::json parameters = satdump::processing::is_processing ? parse_common_flags(argc - 5, &argv[5]) : "";

    // logger->warn("\n" + parameters.dump(4));
    // exit(0);

    // Setup window
    glfwSetErrorCallback(glfw_error_callback);
    if (!glfwInit())
    {
        logger->critical("Could not init GLFW");
        exit(1);
    }

    // GL STUFF
#if GLFW_VERSION_MAJOR > 3 || (GLFW_VERSION_MAJOR == 3 && GLFW_VERSION_MINOR >= 3)
    glfwWindowHint(GLFW_SCALE_TO_MONITOR, GLFW_TRUE);
#endif

    // Decide GL+GLSL versions
    const char *OPENGL_VERSIONS_GLSL[] = {"#version 100", "#version 130", "#version 150"};
    int selected_glsl;
#if defined(IMGUI_IMPL_OPENGL_ES2)
    // GL ES 2.0 + GLSL 100
    selected_glsl = 0;
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
    glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_ES_API);
#elif defined(__APPLE__)
    // GL 3.2 + GLSL 150
    selected_glsl = 2;
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); // 3.2+ only
    glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);           // Required on Mac
#else
    // GL 3.0 + GLSL 130
    selected_glsl = 1;
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
    // glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);  // 3.2+ only
    // glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);            // 3.0+ only
#endif

    GLFWwindow *window = glfwCreateWindow(1000, 600, std::string("SatDump v" + (std::string)SATDUMP_VERSION).c_str(), nullptr, nullptr);
    if (window == nullptr)
    {
        logger->warn("Could not init GLFW Window; falling back to OpenGL 2.1...");
        glfwDefaultWindowHints();
        fallback_gl = true;
        window = glfwCreateWindow(1000, 600, std::string("SatDump v" + (std::string)SATDUMP_VERSION).c_str(), nullptr, nullptr);
        if (window == nullptr)
        {
            pfd::message("SatDump", "Could not start SatDump UI. Please make sure your graphics card supports OpenGL 2.1 or newer",
                         pfd::choice::ok, pfd::icon::error);
            logger->critical("Could not init GLFW Window! Exiting");
            exit(1);
        }
    }

    glfwMakeContextCurrent(window);
    glfwSwapInterval(0); // Disable vsync on loading screen - not needed since frames are only pushed on log updates, and not in a loop
                         // Vsync slows down init process when items are logged quickly

    // Set up texture functions
    bindBaseTextureFunctions();
#ifndef IMGUI_IMPL_OPENGL_ES2
    if (!fallback_gl)
        bindAdvancedTextureFunctions();
#endif

    // Setup Dear ImGui context
    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO &io = ImGui::GetIO();
    (void)io;
    io.IniFilename = NULL;

    logger->debug("Starting with OpenGL %s", (char *)glGetString(GL_VERSION));

    // Setup Platform/Renderer bindings
    ImGui_ImplGlfw_InitForOpenGL(window, true);
#ifndef IMGUI_IMPL_OPENGL_ES2
    if (fallback_gl)
        ImGui_ImplOpenGL2_Init();
    else
#endif
        ImGui_ImplOpenGL3_Init(OPENGL_VERSIONS_GLSL[selected_glsl]);

    // Setup Icon
    GLFWimage img;
    {
        image::Image<uint8_t> image;
        image.load_png(resources::getResourcePath("icon.png"));
        uint8_t *px = new uint8_t[image.width() * image.height() * 4];
        memset(px, 255, image.width() * image.height() * 4);
        img.height = image.height();
        img.width = image.width();

        if (image.channels() == 4)
        {
            for (int y = 0; y < (int)image.height(); y++)
                for (int x = 0; x < (int)image.width(); x++)
                    for (int c = 0; c < 4; c++)
                        px[image.width() * 4 * y + x * 4 + c] = image.channel(c)[image.width() * y + x];
        }
        else if (image.channels() == 3)
        {
            for (int y = 0; y < (int)image.height(); y++)
                for (int x = 0; x < (int)image.width(); x++)
                    for (int c = 0; c < 3; c++)
                        px[image.width() * 4 * y + x * 4 + c] = image.channel(c)[image.width() * y + x];
        }
        image.clear();

        img.pixels = px;
    }

#ifndef _WIN32
    glfwSetWindowIcon(window, 1, &img);
#endif

    // Handle DPI changes
    float display_scale;
#if GLFW_VERSION_MAJOR > 3 || (GLFW_VERSION_MAJOR == 3 && GLFW_VERSION_MINOR >= 3)
    glfwSetWindowContentScaleCallback(window, window_content_scale_callback);
    glfwGetWindowContentScale(window, &display_scale, nullptr);
    display_scale /= style::macos_framebuffer_scale();
#else
    display_scale = 1.0f;
#endif

    // Set font
    style::setFonts(display_scale);

    // Init Loading Screen
    std::shared_ptr<satdump::LoadingScreenSink> loading_screen_sink = std::make_shared<satdump::LoadingScreenSink>(window, display_scale, &img, fallback_gl);
    logger->add_sink(loading_screen_sink);

    // Init SatDump
    satdump::tle_do_update_on_init = false;
    satdump::initSatdump();

    // Check if we need to start a pipeline
    std::optional<satdump::Pipeline> pipeline = satdump::getPipelineFromName(downlink_pipeline);
    if (!pipeline.has_value())
        satdump::processing::is_processing = false;

    // See if we need to add arguments
    satdump::config::main_cfg["cli"] = {};
    if (argc > 1 && !satdump::processing::is_processing)
        satdump::config::main_cfg["cli"] = parse_common_flags(argc - 1, &argv[1]);

    // Init UI
    satdump::initMainUI(display_scale);

    // Shut down loading screen
    logger->del_sink(loading_screen_sink);
    loading_screen_sink.reset();
    glfwSwapInterval(1); // Enable vsync for the rest of the program

    // Set font again to adjust for DPI
    style::setFonts();
#ifndef IMGUI_IMPL_OPENGL_ES2
    if (fallback_gl)
    {
        ImGui_ImplOpenGL2_DestroyFontsTexture();
        ImGui_ImplOpenGL2_CreateFontsTexture();
    }
    else
#endif
    {
        ImGui_ImplOpenGL3_DestroyFontsTexture();
        ImGui_ImplOpenGL3_CreateFontsTexture();
    }

    if (satdump::processing::is_processing)
    {
        satdump::ui_thread_pool.push([&](int)
                                     { satdump::processing::process(downlink_pipeline, input_level, input_file, output_file, parameters); });
    }

    // Set window position
    int x, y, xs, ys;
    bool maximized;
    if (satdump::config::main_cfg["user_interface"]["remember_pos"]["value"].get<bool>() && satdump::config::main_cfg["user_interface"].contains("window"))
    {
        const bool maximized = getValueOrDefault(satdump::config::main_cfg["user_interface"]["window"]["maximized"], false);
        if(maximized)
            glfwMaximizeWindow(window);
        else
        {
            const GLFWvidmode* mode = glfwGetVideoMode(glfwGetPrimaryMonitor());
            x = getValueOrDefault(satdump::config::main_cfg["user_interface"]["window"]["x"], -1);
            y = getValueOrDefault(satdump::config::main_cfg["user_interface"]["window"]["y"], -1);
            xs = getValueOrDefault(satdump::config::main_cfg["user_interface"]["window"]["xs"], -1);
            ys = getValueOrDefault(satdump::config::main_cfg["user_interface"]["window"]["ys"], -1);

            if (x >= 0 && y >= 0  && x < mode->width && y < mode->height && xs > 0 && ys > 0)
            {
                glfwSetWindowPos(window, x, y);
                glfwSetWindowSize(window, xs, ys);
            }
        }
    }

    // TLE
    satdump::ui_thread_pool.push([&](int)
                                 { satdump::autoUpdateTLE(satdump::user_path + "/satdump_tles.txt"); });

    // Attach signal
    signal(SIGINT, sig_handler_ui);
    signal(SIGTERM, sig_handler_ui);

    // Main loop
    do
    {
        // Start the Dear ImGui frame
#ifndef IMGUI_IMPL_OPENGL_ES2
        if (fallback_gl)
            ImGui_ImplOpenGL2_NewFrame();
        else
#endif
            ImGui_ImplOpenGL3_NewFrame();
        ImGui_ImplGlfw_NewFrame();
        ImGui::NewFrame();

        int wwidth, wheight;
        glfwGetWindowSize(window, &wwidth, &wheight);
        // std::cout<<wwidth<<std::endl;

        // User rendering
        satdump::renderMainUI(wwidth, wheight);

        // Rendering
        ImGui::Render();
        int display_w, display_h;
        glfwGetFramebufferSize(window, &display_w, &display_h);
        glViewport(0, 0, display_w, display_h);

        if (satdump::light_theme)
            glClearColor(0.7f, 0.7f, 0.7f, 1.0f);
        else
            glClearColor(0.0666f, 0.0666f, 0.0666f, 1.0f);
        // glClearColor(0.9f, 0.9f, 0.9f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);

#ifndef IMGUI_IMPL_OPENGL_ES2
        if (fallback_gl)
            ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
        else
#endif
            ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());

        glfwSwapBuffers(window);
        glfwPollEvents();
    } while (!glfwWindowShouldClose(window) && !signal_caught);

    //Save window position
    if (satdump::config::main_cfg["user_interface"]["remember_pos"]["value"].get<bool>())
    {
        bool minimized = glfwGetWindowAttrib(window, GLFW_ICONIFIED) == GLFW_TRUE;
        maximized = glfwGetWindowAttrib(window, GLFW_MAXIMIZED) == GLFW_TRUE;
        satdump::config::main_cfg["user_interface"]["window"]["maximized"] = maximized;
        if (!maximized && !minimized)
        {
            glfwGetWindowPos(window, &x, &y);
            glfwGetWindowSize(window, &xs, &ys);
            satdump::config::main_cfg["user_interface"]["window"]["x"] = x;
            satdump::config::main_cfg["user_interface"]["window"]["y"] = y;
            satdump::config::main_cfg["user_interface"]["window"]["xs"] = xs;
            satdump::config::main_cfg["user_interface"]["window"]["ys"] = ys;
        }
    }

    satdump::exitMainUI();

    // Cleanup
#ifndef IMGUI_IMPL_OPENGL_ES2
    if (fallback_gl)
        ImGui_ImplOpenGL2_Shutdown();
    else
#endif
        ImGui_ImplOpenGL3_Shutdown();
    ImGui_ImplGlfw_Shutdown();
    ImGui::DestroyContext();

    glfwDestroyWindow(window);
    glfwTerminate();

    logger->info("UI Exit");

    // If we're doing live processing, we want this to kill all threads quickly. Hence don't call destructors
    if (satdump::processing::is_processing)
#ifdef __APPLE__
        exit(0);
#else
        quick_exit(0);
#endif

    satdump::ui_thread_pool.stop();

    for (int i = 0; i < satdump::ui_thread_pool.size(); i++)
    {
        if (satdump::ui_thread_pool.get_thread(i).joinable())
            satdump::ui_thread_pool.get_thread(i).join();
    }

    logger->info("Exiting!");
}