// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later

// SPDX-FileCopyrightText: 2014 Citra Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <iostream>
#include <memory>
#include <mutex>
#include <regex>
#include <string>
#include "common/settings_enums.h"
#ifdef __EMSCRIPTEN__
#include <emscripten.h>
#endif
#define SDL_MAIN_USE_CALLBACKS 1
#include <SDL3/SDL_main.h>

#include <fmt/ostream.h>

#include "common/logging.h"
#include "common/scm_rev.h"
#include "common/settings.h"
#include "common/string_util.h"
#include "core/core.h"
#include "core/core_timing.h"
#include "core/cpu_manager.h"
#include "core/crypto/key_manager.h"
#include "core/file_sys/registered_cache.h"
#include "core/file_sys/vfs/vfs_real.h"
#include "core/hle/service/am/applet_manager.h"
#include "core/hle/service/filesystem/filesystem.h"
#include "core/loader/loader.h"
#include "frontend_common/config.h"
#include "input_common/main.h"
#include "network/network.h"
#include "sdl_config.h"
#include "video_core/gpu.h"
#include "video_core/rasterizer_interface.h"
#include "video_core/renderer_base.h"
#include "yuzu_cmd/emu_window/emu_window_sdl3.h"
#ifdef HAS_OPENGL
#include "yuzu_cmd/emu_window/emu_window_sdl3_gl.h"
#endif
#include "yuzu_cmd/emu_window/emu_window_sdl3_null.h"
#include "yuzu_cmd/emu_window/emu_window_sdl3_vk.h"

#ifdef _WIN32
// windows.h needs to be included before shellapi.h
#include <windows.h>
#include <shellapi.h>
#include "common/windows/timer_resolution.h"
#endif

#undef _UNICODE
#include <getopt.h>
#ifndef _MSC_VER
#include <unistd.h>
#endif

#ifdef _WIN32
extern "C" {
// tells Nvidia and AMD drivers to use the dedicated GPU by default on laptops with switchable
// graphics
__declspec(dllexport) unsigned long NvOptimusEnablement = 0x00000001;
__declspec(dllexport) int AmdPowerXpressRequestHighPerformance = 1;
}
#endif

static void PrintHelp(const char* argv0) {
    std::cout << "Usage: " << argv0
              << " [options] <filename>\n"
                 "-c, --config          Load the specified configuration file\n"
                 "-f, --fullscreen      Start in fullscreen mode\n"
                 "-g, --game            File path of the game to load\n"
                 "-h, --help            Display this help and exit\n"
                 "-m, --multiplayer=nick:password@address:port"
                 " Nickname, password, address and port for multiplayer\n"
                 "-p, --program         Pass following string as arguments to executable\n"
                 "-u, --user            Select a specific user profile from 0 to 7\n"
                 "-d, --debug           Run the GDB stub on a port from 1 to 65535\n"
                 "-v, --version         Output version information and exit\n";
}

static void PrintVersion() {
    std::cout << "Eden " << Common::g_scm_branch << " " << Common::g_scm_desc << std::endl;
}

static void OnStateChanged(const Network::RoomMember::State& state) {
    switch (state) {
    case Network::RoomMember::State::Idle:
        LOG_DEBUG(Network, "Network is idle");
        break;
    case Network::RoomMember::State::Joining:
        LOG_DEBUG(Network, "Connection sequence to room started");
        break;
    case Network::RoomMember::State::Joined:
        LOG_DEBUG(Network, "Successfully joined to the room");
        break;
    case Network::RoomMember::State::Moderator:
        LOG_DEBUG(Network, "Successfully joined the room as a moderator");
        break;
    default:
        break;
    }
}

static void OnNetworkError(const Network::RoomMember::Error& error) {
    switch (error) {
    case Network::RoomMember::Error::LostConnection:
        LOG_DEBUG(Network, "Lost connection to the room");
        break;
    case Network::RoomMember::Error::CouldNotConnect:
        LOG_ERROR(Network, "Error: Could not connect");
        exit(1);
        break;
    case Network::RoomMember::Error::NameCollision:
        LOG_ERROR(
            Network,
            "You tried to use the same nickname as another user that is connected to the Room");
        exit(1);
        break;
    case Network::RoomMember::Error::IpCollision:
        LOG_ERROR(Network, "You tried to use the same fake IP-Address as another user that is "
                           "connected to the Room");
        exit(1);
        break;
    case Network::RoomMember::Error::WrongPassword:
        LOG_ERROR(Network, "Room replied with: Wrong password");
        exit(1);
        break;
    case Network::RoomMember::Error::WrongVersion:
        LOG_ERROR(Network,
                  "You are using a different version than the room you are trying to connect to");
        exit(1);
        break;
    case Network::RoomMember::Error::RoomIsFull:
        LOG_ERROR(Network, "The room is full");
        exit(1);
        break;
    case Network::RoomMember::Error::HostKicked:
        LOG_ERROR(Network, "You have been kicked by the host");
        break;
    case Network::RoomMember::Error::HostBanned:
        LOG_ERROR(Network, "You have been banned by the host");
        break;
    case Network::RoomMember::Error::UnknownError:
        LOG_ERROR(Network, "UnknownError");
        break;
    case Network::RoomMember::Error::PermissionDenied:
        LOG_ERROR(Network, "PermissionDenied");
        break;
    case Network::RoomMember::Error::NoSuchUser:
        LOG_ERROR(Network, "NoSuchUser");
        break;
    }
}

static void OnMessageReceived(const Network::ChatEntry& msg) {
    std::cout << std::endl << msg.nickname << ": " << msg.message << std::endl << std::endl;
}

static void OnStatusMessageReceived(const Network::StatusMessageEntry& msg) {
    std::string message = [&]() {
        switch (msg.type) {
        case Network::IdMemberJoin:
            return fmt::format("{} has joined", msg.nickname);
        case Network::IdMemberLeave:
            return fmt::format("{} has left", msg.nickname);
        case Network::IdMemberKicked:
            return fmt::format("{} has been kicked", msg.nickname);
        case Network::IdMemberBanned:
            return fmt::format("{} has been banned", msg.nickname);
        case Network::IdAddressUnbanned:
            return fmt::format("{} has been unbanned", msg.nickname);
        default:
            return std::string{};
        }
    }();
    if (!message.empty())
        std::cout << std::endl << "* " << message << std::endl << std::endl;
}

struct SdlState {
    Core::System system{};
    std::unique_ptr<EmuWindow_SDL3> emu_window;
};

extern "C" SDL_AppResult SDL_AppInit(void **appstate, int argc, char **argv) {
    SdlState* state = new SdlState();

#ifdef _WIN32
    if (AttachConsole(ATTACH_PARENT_PROCESS)) {
        freopen("CONOUT$", "wb", stdout);
        freopen("CONOUT$", "wb", stderr);
    }
#endif

    Common::Log::Initialize();
    Common::Log::SetColorConsoleBackendEnabled(true);
    Common::Log::Start();

    int option_index = 0;
#ifdef _WIN32
    int argc_w;
    auto argv_w = CommandLineToArgvW(GetCommandLineW(), &argc_w);
    if (argv_w == nullptr) {
        LOG_CRITICAL(Frontend, "Failed to get command line arguments");
        return SDL_APP_FAILURE;
    }
#endif
    std::string filepath;
    std::optional<std::string> config_path{};
    std::string program_args;
    std::optional<int> selected_user{};
    std::optional<u16> override_gdb_port{};
    bool use_multiplayer = false;
    bool fullscreen = false;
    bool force_null_render = false;
    bool force_single_core = false;
    std::string nickname{};
    std::string password{};
    std::string address{};
    std::string input_profile{};
    std::optional<std::string> log_filter{};
    u16 port = Network::DefaultRoomPort;

    static struct option long_options[] = {
        // clang-format off
        {"debug", no_argument, 0, 'd'},
        {"config", required_argument, 0, 'c'},
        {"fullscreen", no_argument, 0, 'f'},
        {"help", no_argument, 0, 'h'},
        {"game", required_argument, 0, 'g'},
        {"multiplayer", required_argument, 0, 'm'},
        {"program", optional_argument, 0, 'p'},
        {"user", required_argument, 0, 'u'},
        {"version", no_argument, 0, 'v'},
        {"input-profile", no_argument, 0, 'i'},
        {"null-render", no_argument, 0, 'n'},
        {"singlecore", no_argument, 0, 's'},
        {"filter", no_argument, 0, 'x'},
        {0, 0, 0, 0},
        // clang-format on
    };

    while (optind < argc) {
        int arg = getopt_long(argc, argv, "g:fhvcip::c:u:d:", long_options, &option_index);
        if (arg != -1) {
            switch (char(arg)) {
            case 'd':
                override_gdb_port = uint16_t(atoi(optarg));
                break;
            case 'c':
                config_path = optarg;
                break;
            case 'f':
                fullscreen = true;
                LOG_INFO(Frontend, "Starting in fullscreen mode...");
                break;
            case 'h':
                PrintHelp(argv[0]);
                return SDL_APP_FAILURE;
            case 'g':
                filepath = std::string(optarg);
                break;
            case 'i': {
                input_profile = std::string(optarg);
                break;
            }
            case 'm': {
                use_multiplayer = true;
                const std::string str_arg(optarg);
                // regex to check if the format is nickname:password@ip:port
                // with optional :password
                const std::regex re("^([^:]+)(?::(.+))?@([^:]+)(?::([0-9]+))?$");
                if (!std::regex_match(str_arg, re)) {
                    std::cout << "Wrong format for option --multiplayer\n";
                    PrintHelp(argv[0]);
                    return SDL_APP_FAILURE;
                }

                std::smatch match;
                std::regex_search(str_arg, match, re);
                ASSERT(match.size() == 5);
                nickname = match[1];
                password = match[2];
                address = match[3];
                if (!match[4].str().empty()) {
                    port = u16(std::strtoul(match[4].str().c_str(), nullptr, 0));
                }
                std::regex nickname_re("^[a-zA-Z0-9._\\- ]+$");
                if (!std::regex_match(nickname, nickname_re)) {
                    LOG_ERROR(Frontend, "Nickname is not valid. Must be 4 to 20 alphanumeric characters");
                    return SDL_APP_FAILURE;
                }
                if (address.empty()) {
                    LOG_ERROR(Frontend, "Address to room must not be empty");
                    return SDL_APP_FAILURE;
                }
                break;
            }
            case 'p':
                program_args = argv[optind];
                ++optind;
                break;
            case 'u':
                selected_user = atoi(optarg);
                break;
            case 'v':
                PrintVersion();
                return SDL_APP_FAILURE;
            case 'n':
                force_null_render = true;
                break;
            case 's':
                force_single_core = true;
                break;
            case 'x':
                log_filter = argv[optind];
                ++optind;
                break;
            }
        } else {
#ifdef _WIN32
            filepath = Common::UTF16ToUTF8(argv_w[optind]);
#else
            filepath = argv[optind];
#endif
            optind++;
        }
    }

    SdlConfig config{config_path};

    // apply the log_filter setting
    // the logger was initialized before and doesn't pick up the filter on its own
    Common::Log::Filter filter;
    filter.ParseFilterString(log_filter.value_or(Settings::values.log_filter.GetValue()));
    Common::Log::SetGlobalFilter(filter);

    if (!program_args.empty()) {
        Settings::values.program_args = program_args;
    }

    if (!input_profile.empty()) {
        auto& players = Settings::values.players.GetValue();
        players[0].profile_name = input_profile;
    }

    if (selected_user.has_value()) {
        Settings::values.current_user = std::clamp(*selected_user, 0, 7);
    }

    if (override_gdb_port.has_value()) {
        Settings::values.use_gdbstub = true;
        Settings::values.gdbstub_port = *override_gdb_port;
    }

    if (force_single_core) {
        Settings::values.use_multi_core = false;
    }

    if (force_null_render) {
        Settings::values.renderer_backend = Settings::RendererBackend::Null;
    }

#ifdef _WIN32
    LocalFree(argv_w);
#endif

    if (filepath.empty()) {
        LOG_CRITICAL(Frontend, "Failed to load ROM: No ROM specified");
        return SDL_APP_FAILURE;
    }

    state->system.Initialize();

    InputCommon::InputSubsystem input_subsystem{};

    // Apply the command line arguments
    state->system.ApplySettings();

    switch (Settings::values.renderer_backend.GetValue()) {
#ifdef HAS_OPENGL
    case Settings::RendererBackend::OpenGL_GLSL:
    case Settings::RendererBackend::OpenGL_GLASM:
    case Settings::RendererBackend::OpenGL_SPIRV:
        state->emu_window = std::make_unique<EmuWindow_SDL3_GL>(&input_subsystem, state->system, fullscreen);
        break;
#endif
    case Settings::RendererBackend::Vulkan:
        state->emu_window = std::make_unique<EmuWindow_SDL3_VK>(&input_subsystem, state->system, fullscreen);
        break;
    case Settings::RendererBackend::Null:
        state->emu_window = std::make_unique<EmuWindow_SDL3_Null>(&input_subsystem, state->system, fullscreen);
        break;
    default:
        LOG_CRITICAL(Frontend, "Invalid renderer backend");
        return SDL_APP_FAILURE;
    }

#ifdef _WIN32
    Common::Windows::SetCurrentTimerResolutionToMaximum();
    state->system.CoreTiming().SetTimerResolutionNs(Common::Windows::GetCurrentTimerResolution());
#endif

    state->system.SetContentProvider(std::make_unique<FileSys::ContentProviderUnion>());
    state->system.SetFilesystem(std::make_shared<FileSys::RealVfsFilesystem>());
    state->system.GetFileSystemController().CreateFactories(*state->system.GetFilesystem());
    state->system.GetUserChannel().clear();

    Service::AM::FrontendAppletParameters load_parameters{
        .applet_id = Service::AM::AppletId::Application,
    };
    const Core::SystemResultStatus load_result = state->system.Load(*state->emu_window, filepath, load_parameters);
    switch (load_result) {
    case Core::SystemResultStatus::Success:
        break; // Expected case
    case Core::SystemResultStatus::ErrorGetLoader:
        LOG_CRITICAL(Frontend, "Failed to obtain loader for {}!", filepath);
        return SDL_APP_FAILURE;
    case Core::SystemResultStatus::ErrorLoader:
        LOG_CRITICAL(Frontend, "Failed to load ROM!");
        return SDL_APP_FAILURE;
    case Core::SystemResultStatus::ErrorNotInitialized:
        LOG_CRITICAL(Frontend, "CPUCore not initialized");
        return SDL_APP_FAILURE;
    case Core::SystemResultStatus::ErrorVideoCore:
        LOG_CRITICAL(Frontend, "Failed to initialize VideoCore!");
        return SDL_APP_FAILURE;
    default:
        const u16 loader_id = u16(Core::SystemResultStatus::ErrorLoader);
        const u16 error_id = u16(load_result) - loader_id;
        LOG_CRITICAL(Frontend,
            "While attempting to load the ROM requested, an error occurred. Please "
            "refer to the Eden wiki for more information or the Eden discord for "
            "additional help.\n\nError Code: {:04X}-{:04X}\nError Description: {}",
            loader_id, error_id, Loader::ResultStatus(error_id));
        return SDL_APP_FAILURE;
    }

    if (use_multiplayer) {
        if (auto member = Network::GetRoomMember().lock()) {
            member->BindOnChatMessageReceived(OnMessageReceived);
            member->BindOnStatusMessageReceived(OnStatusMessageReceived);
            member->BindOnStateChanged(OnStateChanged);
            member->BindOnError(OnNetworkError);
            LOG_DEBUG(Network, "Start connection to {}:{} with nickname {}", address, port, nickname);
            member->Join(nickname, address.c_str(), port, 0, Network::NoPreferredIP, password);
        } else {
            LOG_ERROR(Network, "Could not access RoomMember");
            return SDL_APP_FAILURE;
        }
    }

    // Core is loaded, start the GPU (makes the GPU contexts current to this thread)
    state->system.GPU().Start();
    state->system.GetCpuManager().OnGpuReady();

    if (Settings::values.use_disk_shader_cache.GetValue()) {
        state->system.Renderer().ReadRasterizer()->LoadDiskResources(
            state->system.GetApplicationProcessProgramID(), std::stop_token{},
            [](VideoCore::LoadCallbackStage, size_t value, size_t total) {});
    }

    // don't do anything, SDL3 already exists for us :D
    state->system.RegisterExitCallback([] {});

    // QLaunch launched applications (should) now reload shader cache.
    static std::mutex shader_cache_reload_mutex;
    state->system.RegisterApplicationChangedCallback([&state](u64 changed_program_id) {
        if (!Settings::values.use_disk_shader_cache.GetValue()) {
            return;
        }

        std::scoped_lock lk{shader_cache_reload_mutex};

        LOG_INFO(Frontend, "Reloading disk shader cache for {:016X}", changed_program_id);

        state->system.Pause();
        state->system.GPU().WaitForIdle();
        state->system.GPU().ObtainContext();

        state->system.Renderer().ReadRasterizer()->LoadDiskResources(
            changed_program_id, std::stop_token{},
            [](VideoCore::LoadCallbackStage, size_t, size_t) {});

        state->system.GPU().ReleaseContext();
        state->system.Run();
    });

    void(state->system.Run());
    if (state->system.DebuggerEnabled())
        state->system.InitializeDebugger();
    return SDL_APP_SUCCESS;
}
extern "C" SDL_AppResult SDL_AppIterate(void *appstate) {
    SdlState *state = (SdlState *)appstate;
    return state->emu_window->IsOpen() ? SDL_APP_CONTINUE : SDL_APP_SUCCESS;
}
extern "C" SDL_AppResult SDL_AppEvent(void *appstate, SDL_Event *event) {
    SdlState *state = (SdlState *)appstate;
    state->emu_window->OnEvent(*event);
    return SDL_APP_SUCCESS;
}
extern "C" void SDL_AppQuit(void *appstate, SDL_AppResult result) {
    SdlState *state = (SdlState *)appstate;
    state->system.DetachDebugger();
    void(state->system.Pause());
    state->system.ShutdownMainProcess();
    delete state;
}

#define VMA_IMPLEMENTATION
#include "video_core/vulkan_common/vma.h"
