#include "RendererBackend.h"
#include <assets/assets.h>
#include <vector>
#include "IconsForkAwesome.h"
#include "config.h"
#include <SDL_image.h>
#include <string>
#include <tuple>
#include <initializer_list>
#include "theme.h"
#include "imgui_stdlib.h"
#include "imgui_impl_sdl2.h"
#include "imgui_impl_sdlrenderer2.h"
#include "base85.h"
#include <thread>
#include <translation.hpp>
#include <log.hpp>
#include <options.hpp>
#include <web_functions.hpp>
using std::vector;
using namespace Looper::Options;
void RendererBackend::on_resize() {
#ifdef __EMSCRIPTEN__
    int32_t x, y;
    get_size(&x, &y);
    SDL_SetWindowSize(window, (int)x, (int)y);
    UpdateScale();
#endif
}
static RendererBackend *renderer_backend;

void RendererBackend::resize_static() {
    renderer_backend->resize_needed = true;
}
void main_loop() {
#ifdef __EMSCRIPTEN__
    if (!renderer_backend->started) {
        renderer_backend->BackendInit();
    }
#endif
    renderer_backend->LoopFunction();
#ifdef __EMSCRIPTEN__
    if (renderer_backend->done) {
        renderer_backend->BackendDeinit();
        emscripten_cancel_main_loop();
    }
#endif
}

struct FontData {
    const ImWchar *ranges;
    std::map<std::string, std::pair<const char *, double>> data;
    void Init(const ImWchar *ranges_in, std::map<std::string, std::pair<const char *, double>> data_in) {
        ranges = ranges_in;
        data = data_in;
    }
    FontData(const ImWchar *ranges, std::initializer_list<std::pair<std::string, std::pair<const char*, double>>> data) {
        std::map<std::string, std::pair<const char*, double>> out_data;
        for (auto pair : data) {
            out_data[pair.first] = pair.second;
        }
        Init(ranges, out_data);
    }
    FontData(const ImWchar *ranges, std::initializer_list<std::tuple<std::string, const char*, double>> data) {
        std::map<std::string, std::pair<const char*, double>> out_data;
        for (auto tuple : data) {
            std::pair<const char*, double> outPair = {std::get<1>(tuple), std::get<2>(tuple)};
            out_data[std::get<0>(tuple)] = outPair;
        }
        Init(ranges, out_data);
    }
    FontData(const ImWchar *ranges, std::map<std::string, std::pair<const char*, double>> data) {
        Init(ranges, data);
    }
};
void RendererBackend::BackendDeinit() {
    ImGuiIO& io = ImGui::GetIO(); (void)io;
    void *IniFilename = (void*)io.IniFilename;
    // Cleanup
    ImGui_ImplSDLRenderer2_Shutdown();
    ImGui_ImplSDL2_Shutdown();
    ImGui::DestroyContext();

    SDL_DestroyRenderer(rend);
    SDL_DestroyWindow(window);
    IMG_Quit();
    SDL_Quit();
    free(IniFilename);
    Deinit();
    renderer_backend = nullptr;
}
bool RendererBackend::isTouchScreenMode() {
    return touchScreenModeOverride.value_or(SDL_GetNumTouchDevices() > 0);
}
void RendererBackend::QueueUpdateScale() {
    update_scale = true;
}
void RendererBackend::LoopFunction() {
    if (update_scale) {
        UpdateScale();
        update_scale = false;
    }
    #ifndef __EMSCRIPTEN__
    SDL_RenderSetVSync(rend, vsync ? 1 : 0);
    #endif
    ImGuiIO& io = ImGui::GetIO(); (void)io;
    if (resize_needed) {
        on_resize();
    }
    auto next_frame = std::chrono::steady_clock::now() + std::chrono::milliseconds(1000 / (framerate == 0 ? 60 : framerate));
    // Poll and handle events (inputs, window resize, etc.)
    // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
    // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
    // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
    // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
    SDL_Event event;
    while (SDL_PollEvent(&event))
    {
        ImGui_ImplSDL2_ProcessEvent(&event);
        if (event.type == SDL_QUIT)
            done = true;
        if (event.type == SDL_WINDOWEVENT) {
            if (event.window.event == SDL_WINDOWEVENT_RESIZED) {
                window_width = event.window.data1 / scale;
                window_height = event.window.data2 / scale;
                //SDL_GetWindowSize(window, &window_width, &window_height);
            }
            if (event.window.event == SDL_WINDOWEVENT_DISPLAY_CHANGED) {
                UpdateScale();
            }
            if (event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window)) {
                done = true;
            }
        }
        if (event.type == SDL_DROPFILE) {
            if (event.drop.file != NULL) {
                Drop(std::string(event.drop.file));
                free(event.drop.file);
            }
        }
    }
    bool touchScreenMode = isTouchScreenMode();
    if (touchScreenMode) {
        io.ConfigFlags |= ImGuiConfigFlags_IsTouchScreen;
    } else {
        io.ConfigFlags &= ~ImGuiConfigFlags_IsTouchScreen;
    }
    // Start the Dear ImGui frame
    ImGui_ImplSDLRenderer2_NewFrame();
    ImGui_ImplSDL2_NewFrame();
    ImGui::NewFrame();
    // Run the GUI
    GuiFunction();
    // Rendering
    ImGui::Render();
    SDL_SetRenderDrawColor(rend, (Uint8)(clear_color.x * clear_color.w * 255), (Uint8)(clear_color.y * clear_color.w * 255), (Uint8)(clear_color.z * clear_color.w * 255), (Uint8)(clear_color.w * 255));
    SDL_RenderClear(rend);
    // Tell ImGui to render.
    ImGui_ImplSDLRenderer2_RenderDrawData(ImGui::GetDrawData(), rend);


    // Swap the buffers, and do VSync if enabled.
    SDL_RenderPresent(rend);
    // If not doing VSync, wait until the next frame needs to be rendered.
    if (!vsync) {
        std::this_thread::sleep_until(next_frame);
    }
}

std::map<std::string, ImFont *> add_font(FontData data_vec, double scale) {
    ImGuiIO& io = ImGui::GetIO();
    std::map<std::string, ImFont*> output;
    for (auto value : data_vec.data) {
        ImFont* font = nullptr;
        std::string id = value.first;
        const char *data = value.second.first;
        double size = value.second.second * scale;
        {
            ImFontConfig font_cfg = ImFontConfig();
            font_cfg.SizePixels = size;
            font_cfg.OversampleH = font_cfg.OversampleV = 1;
            font_cfg.PixelSnapH = true;
            if (font_cfg.SizePixels <= 0.0f)
                font_cfg.SizePixels = 13.0f * 1.0f;
            //font_cfg.EllipsisChar = (ImWchar)0x0085;
            //font_cfg.GlyphOffset.y = 1.0f * IM_FLOOR(font_cfg.SizePixels / 13.0f);  // Add +1 offset per 13 units

            const char *ttf_compressed_base85 = data;
            const ImWchar *glyph_ranges = data_vec.ranges;
            font = io.Fonts->AddFontFromMemoryCompressedBase85TTF(ttf_compressed_base85,
                                                                           font_cfg.SizePixels,
                                                                           &font_cfg, glyph_ranges);
        }
        {
            ImFontConfig config;
            config.MergeMode = true;
            config.GlyphMinAdvanceX = size;
            config.SizePixels = size;
            config.DstFont = font;
            static const ImWchar icon_ranges[] = {ICON_MIN_FK, ICON_MAX_FK, 0};
            io.Fonts->AddFontFromMemoryCompressedBase85TTF(forkawesome_compressed_data_base85,
                                                           float(size), &config, icon_ranges);
        }
        output[id] = font;
    }
    return output;
}
RendererBackend::RendererBackend() {
}
RendererBackend::~RendererBackend() {
    DEBUG.writeln("Renderer backend destructor run.");
    renderer_backend = nullptr;
}
void RendererBackend::SetWindowTitle(const char *title) {
    SDL_SetWindowTitle(window, title);
}
void RendererBackend::GuiFunction() {
    // Do nothing by default.
}
void RendererBackend::UpdateScale() {
    double prevScale = scale;
    const double defaultDPI =
    #ifdef __APPLE__
        72.0;
    #else
        96.0;
    #endif
    if (scaleOverride.has_value()) {
        scale = scaleOverride.value();
    } else {
#ifdef __EMSCRIPTEN__
        scale = get_dpi();
#else
        float dpi = defaultDPI;
        if (SDL_GetDisplayDPI(SDL_GetWindowDisplayIndex(window), NULL, &dpi, NULL) == 0){
            scale = dpi / defaultDPI;
        } else {
            WARNING.writeln("DPI couldn't be determined!");
            scale = 1.0;
        }
#ifndef __ANDROID__
        SDL_SetWindowSize(window, window_width * scale, window_height * scale);
#endif
#endif
    }
    AddFonts();
    OnScale((float)scale);
}
void RendererBackend::OnScale(float scale) {
    theme->Apply(accent_color, scale);
}
void RendererBackend::SetWindowSize(int w, int h) {
#if !(defined(__ANDROID__) || defined(__EMSCRIPTEN__))
    window_width = w;
    window_height = h;
    SDL_SetWindowSize(window, w * scale, h * scale);
#endif
}
void RendererBackend::GetWindowsize(int *w, int *h) {
    int ww, wh;
    SDL_GetWindowSize(window, &ww, &wh);
    ww /= scale;
    wh /= scale;
    if (w) *w = ww;
    if (h) *h = wh;
}
void RendererBackend::AddFonts() {
    ImGui_ImplSDLRenderer2_DestroyFontsTexture();
    auto& io = ImGui::GetIO(); (void)io;
    io.Fonts->Clear();
    std::string font_type = get_option<std::string>("font_type", "default");
    std::string default_font = "default";
    std::string jp_font = "japanese";
    auto glyph_ranges_default = io.Fonts->GetGlyphRangesDefault();
    auto glyph_ranges_jp = io.Fonts->GetGlyphRangesJapanese();
    FontData latin(glyph_ranges_default, {{"normal", notosans_regular_compressed_data_base85, 13}, {"title", notosans_thin_compressed_data_base85, 32}});
    FontData jp(glyph_ranges_jp, {{"normal", notosansjp_regular_compressed_data_base85, 13}, {"title", notosansjp_thin_compressed_data_base85, 32}});
    std::map<std::string, ImFont*> font_map;
    if (font_type == jp_font) {
        font_map = add_font(jp, scale);
    } else {
        font_map = add_font(latin, scale);
    }
    title = font_map["title"];
    io.FontDefault = font_map["normal"];
    ImGui_ImplSDLRenderer2_CreateFontsTexture();
}
#ifdef __EMSCRIPTEN__
static EM_BOOL resize_callback(int event_type, const EmscriptenUiEvent *event, void *userdata) {
    RendererBackend::resize_static();
    return EM_FALSE;
}
#endif
void RendererBackend::BackendInit() {
    setup_locale("neko_player");
    DEBUG.writefln("Loaded locale '%s' from '%s'...", CURRENT_LANGUAGE, LOCALE_DIR);
    DEBUG.writefln("Locale name: %s", _TR_CTX("Language name", "English (United States)"));
    bool enable_kms = std::getenv("LAP_KMS") != nullptr;
    SDL_SetHint(SDL_HINT_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR, "false");
    SDL_SetHint(SDL_HINT_APP_NAME, NAME);
    // Setup SDL
    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_GAMECONTROLLER) != 0)
    {
        ERROR.writefln("Error: %s", SDL_GetError());
        throw std::exception();
    }
    if (std::string(SDL_GetCurrentVideoDriver()) == "KMSDRM") {
        enable_kms = true;
    }
    IMG_Init(IMG_INIT_PNG|IMG_INIT_WEBP);
    #ifdef __ANDROID__
    prefPath = SDL_AndroidGetInternalStoragePath();
    #else
    prefPath = SDL_GetPrefPath("Catmeow72", NAME);
    #endif
    Theme::prefPath = prefPath;

    // From 2.0.18: Enable native IME.
#ifdef SDL_HINT_IME_SHOW_UI
    SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");
#endif
    SDL_WindowFlags window_flags = (SDL_WindowFlags)(SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI | SDL_WINDOW_HIDDEN);
    SDL_CreateWindowAndRenderer(window_width, window_height, window_flags, &window, &rend);

#ifndef __ANDROID__
    SDL_SetWindowMinimumSize(window, window_width, window_height);
    if (enable_kms) {
        SDL_SetWindowFullscreen(window, SDL_WINDOW_FULLSCREEN_DESKTOP);
    }
#endif
    SDL_EventState(SDL_DROPFILE, SDL_ENABLE);
    SDL_Surface* icon = IMG_Load_RW(SDL_RWFromConstMem(icon_data, icon_size), 1);
    SDL_SetWindowIcon(window, icon);

    // Setup Dear ImGui context
    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO& io = ImGui::GetIO(); (void)io;
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
    if (SDL_GetNumTouchDevices() > 0) {
        io.ConfigFlags |= ImGuiConfigFlags_IsTouchScreen;
    }
    //io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;
    io.IniFilename = strdup((std::string(prefPath) + "imgui.ini").c_str());
    if (enable_kms) {
        io.MouseDrawCursor = true;
    }
    //io.ConfigViewportsNoAutoMerge = true;
    //io.ConfigViewportsNoTaskBarIcon = true;

    //ImGui::StyleColorsLight();

    // Setup Platform/Renderer backends
    ImGui_ImplSDL2_InitForSDLRenderer(window, rend);
    ImGui_ImplSDLRenderer2_Init(rend);
    // Load Fonts
    // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
    // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.
    // - If the file cannot be loaded, the function will return a nullptr. Please handle those errors in your application (e.g. use an assertion, or display an error and quit).
    // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call.
    // - Use '#define IMGUI_ENABLE_FREETYPE' in your imconfig file to use Freetype for higher quality font rendering.
    // - Read 'docs/FONTS.md' for more instructions and details.
    // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ !
    //io.Fonts->AddFontDefault();
    //io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\segoeui.ttf", 18.0f);
    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f);
    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);
    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);
    //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, nullptr, io.Fonts->GetGlyphRangesJapanese());
    //IM_ASSERT(font != nullptr);
    theme = new Theme(false);

    UpdateScale();

    #ifdef __ANDROID__
    userdir = SDL_AndroidGetExternalStoragePath();
    #else
    userdir = std::getenv(
    #ifdef _WIN32
    "UserProfile"
    #else
    "HOME"
    #endif
    );
    #endif
    #ifndef __EMSCRIPTEN__
    SDL_RenderSetVSync(rend, vsync ? 1 : 0);
    #endif
    theme->Apply(accent_color, (float)scale);
    Init();
    SDL_ShowWindow(window);
    started = true;
}
int RendererBackend::Run() {
    framerate = 60;
    started = false;
    renderer_backend = this;
#ifdef __EMSCRIPTEN__
    emscripten_set_main_loop(&main_loop, 0, 1);
#else
    try {
        BackendInit();
    } catch (std::exception &e) {
        ERROR.writefln("Error occurred during initialization: %s", e.what());
        return -1;
    }
    started = true;
    while (!done)
    {
        LoopFunction();
    }
    BackendDeinit();
#endif
    return 0;
}
void RendererBackend::Init() {
    // Do nothing by default.
}
void RendererBackend::Deinit() {
    // Do nothing by default.
}
void RendererBackend::Drop(std::string file) {
    // Do nothing by default.
}