#include <common/defs.hpp>
#include <renderer/Renderer.hpp>
#include <games/Game.hpp>

#include <SDL3/SDL.h>
#include <SDL3/SDL_video.h>
#include <GL/glew.h>
#include <GL/gl.h>

#include <imgui.h>
#include <imgui_impl_opengl3.h>
#include <imgui_impl_sdl3.h>

#include <iostream>
#include <memory>
#include <cstdlib>
#include <assert.h>


Game::GameType DrawGameMenu()
{
    Game::GameType type = Game::no_game;

    //ImGuiWindowFlags flags = ImGuiWindowFlags_NoNav | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoBackground | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove;
    ImGuiWindowFlags flags = 0;

    ImGui::Begin("Game Selection", nullptr, flags);
    if (ImGui::Button("Tetris")) {
        type = Game::tetris;
    }
    if (ImGui::Button("Minesweeper")) {
        type = Game::minesweeper;
    }
    if (ImGui::Button("Snake")) {
        type = Game::snake;
    }
    ImGui::End();


    Color clear_color = {0.4f, 0.4f, 0.4f, 1.0f};
    g_renderer.SetCameraSize(4.0f, 3.0f);
    g_renderer.Clear(clear_color);


    return type;
}


void
DrawPerformanceInfo()
{
    ImGuiIO& io = ImGui::GetIO();
    ImGuiWindowFlags flags = ImGuiWindowFlags_NoNav | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoBackground | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove;

    ImGui::SetNextWindowPos(ImVec2(io.DisplaySize.x - 200, 0));
    ImGui::Begin("Performance", nullptr, flags);
    ImGui::Text("%.3f ms/frame (%.1f FPS)", 1000.0f / io.Framerate, io.Framerate);
    ImGui::End();
}


SDL_Window*
CreateWindow()
{
    if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMEPAD)) {
        std::cerr << "Failed to init SDL3: " << SDL_GetError() << '\n';
        return nullptr;
    }


    const char* glsl_version = "#version 130";
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);

    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
    SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);


    SDL_Window *window = SDL_CreateWindow("fsarcade", 1024, 768, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN | SDL_WINDOW_HIGH_PIXEL_DENSITY);
    if (!window) {
        std::cerr << "Failed to create SDL_window: " << SDL_GetError() << '\n';
        return nullptr;
    }

    SDL_GLContext sdl_gl_context = SDL_GL_CreateContext(window);
    if (!sdl_gl_context) {
        std::cerr << "Failed to create SDL_GLContext: " << SDL_GetError() << '\n';
        SDL_DestroyWindow(window);
        return nullptr;
    }


    GLenum glew_error = glewInit();
    if (glew_error != GLEW_OK)
    {
        SDL_GL_DestroyContext(sdl_gl_context);
        SDL_DestroyWindow(window);
        std::cerr << "Failed to init glew: " << glewGetErrorString(glew_error) << '\n';
        return nullptr;
    }


    SDL_GL_MakeCurrent(window, sdl_gl_context);
    SDL_GL_SetSwapInterval(1); // enable vsync
    SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
    SDL_ShowWindow(window);


    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO& io = ImGui::GetIO();
    io.IniFilename = NULL;
    io.LogFilename = NULL;
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
    io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;

    ImGui::StyleColorsDark();
    ImGui_ImplSDL3_InitForOpenGL(window, sdl_gl_context);
    ImGui_ImplOpenGL3_Init(glsl_version);

    return window;
}


int
main(int argc, char **argv)
{
    SDL_Window* window = CreateWindow();
    if (!window) {
        return 0;
    }


    g_renderer.Init(window);
    std::unique_ptr<Game> game = nullptr;


    std::vector<SDL_Event> game_events;
    game_events.reserve(32);


    for (;;) {
        ImGui_ImplOpenGL3_NewFrame();
        ImGui_ImplSDL3_NewFrame();
        ImGui::NewFrame();


        size_t cur_game_events = 0;
        size_t max_game_events = game_events.max_size();

        SDL_Event event;
        while (cur_game_events < max_game_events && SDL_PollEvent(&event)) {
            if (event.type == SDL_EVENT_KEY_DOWN ||
                event.type == SDL_EVENT_MOUSE_BUTTON_DOWN)
            {
                game_events.emplace_back(event);
                cur_game_events++;
            }
            ImGui_ImplSDL3_ProcessEvent(&event);

            if (event.type == SDL_EVENT_QUIT)
                return 0;
            if (event.type == SDL_EVENT_WINDOW_CLOSE_REQUESTED && event.window.windowID == SDL_GetWindowID(window))
                return 0;
            if (event.type == SDL_EVENT_WINDOW_DESTROYED && event.window.windowID == SDL_GetWindowID(window)) {
                return 0;
            }
        }


        int w, h;
        SDL_GetWindowSize(window, &w, &h);
        g_renderer.SetScreenSize(w, h);


        if (game) {
            bool keep_game_running = game->Update(game_events);
            if (!keep_game_running) {
                game.reset();
            }
        }
        else {
            Game::GameType type = DrawGameMenu();
            if (type != Game::no_game) {
                game = Game::Select(type);
            }
        }
        game_events.clear();


        g_renderer.Draw();
        ImGui::Render();
        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());

        SDL_GL_SwapWindow(window);
        g_renderer.Reset();
    }

    return 0;
}