#include <vcpkg/base/system_headers.h>

#include <vcpkg/base/chrono.h>
#include <vcpkg/base/files.h>
#include <vcpkg/base/pragmas.h>
#include <vcpkg/base/strings.h>
#include <vcpkg/base/system.debug.h>
#include <vcpkg/base/system.print.h>
#include <vcpkg/base/system.process.h>

#include <vcpkg/commands.contact.h>
#include <vcpkg/commands.h>
#include <vcpkg/commands.version.h>
#include <vcpkg/globalstate.h>
#include <vcpkg/help.h>
#include <vcpkg/input.h>
#include <vcpkg/metrics.h>
#include <vcpkg/paragraphs.h>
#include <vcpkg/userconfig.h>
#include <vcpkg/vcpkglib.h>

#include <cassert>
#include <fstream>
#include <memory>
#include <random>

#if defined(_WIN32)
#pragma comment(lib, "ole32")
#pragma comment(lib, "shell32")
#endif

using namespace vcpkg;

// 24 hours/day * 30 days/month * 6 months
static constexpr int SURVEY_INTERVAL_IN_HOURS = 24 * 30 * 6;

// Initial survey appears after 10 days. Therefore, subtract 24 hours/day * 10 days
static constexpr int SURVEY_INITIAL_OFFSET_IN_HOURS = SURVEY_INTERVAL_IN_HOURS - 24 * 10;

static void invalid_command(const std::string& cmd)
{
    System::print2(System::Color::error, "invalid command: ", cmd, '\n');
    print_usage();
    Checks::exit_fail(VCPKG_LINE_INFO);
}

static void inner(vcpkg::Files::Filesystem& fs, const VcpkgCmdArguments& args)
{
    Metrics::g_metrics.lock()->track_property("command", args.command);
    if (args.command.empty())
    {
        print_usage();
        Checks::exit_fail(VCPKG_LINE_INFO);
    }

    static const auto find_command = [&](auto&& commands) {
        auto it = Util::find_if(commands, [&](auto&& commandc) {
            return Strings::case_insensitive_ascii_equals(commandc.name, args.command);
        });
        using std::end;
        if (it != end(commands))
        {
            return &*it;
        }
        else
        {
            return static_cast<decltype(&*it)>(nullptr);
        }
    };

    if (const auto command_function = find_command(Commands::get_available_basic_commands()))
    {
        return command_function->function->perform_and_exit(args, fs);
    }

    const VcpkgPaths paths(fs, args);
    paths.track_feature_flag_metrics();

    fs.current_path(paths.root, VCPKG_LINE_INFO);
    if ((args.command == "install" || args.command == "remove" || args.command == "export" ||
         args.command == "update") &&
        !args.output_json())
    {
        Commands::Version::warn_if_vcpkg_version_mismatch(paths);
        std::string surveydate = *GlobalState::g_surveydate.lock();
        auto maybe_surveydate = Chrono::CTime::parse(surveydate);
        if (auto p_surveydate = maybe_surveydate.get())
        {
            const auto now = Chrono::CTime::get_current_date_time().value_or_exit(VCPKG_LINE_INFO);
            const auto delta = now.to_time_point() - p_surveydate->to_time_point();
            if (std::chrono::duration_cast<std::chrono::hours>(delta).count() > SURVEY_INTERVAL_IN_HOURS)
            {
                std::default_random_engine generator(
                    static_cast<unsigned int>(now.to_time_point().time_since_epoch().count()));
                std::uniform_int_distribution<int> distribution(1, 4);

                if (distribution(generator) == 1)
                {
                    Metrics::g_metrics.lock()->track_property("surveyprompt", "true");
                    System::print2(
                        System::Color::success,
                        "Your feedback is important to improve Vcpkg! Please take 3 minutes to complete our survey "
                        "by running: vcpkg contact --survey\n");
                }
            }
        }
    }

    if (const auto command_function = find_command(Commands::get_available_paths_commands()))
    {
        return command_function->function->perform_and_exit(args, paths);
    }

    Triplet default_triplet = vcpkg::default_triplet(args);
    Input::check_triplet(default_triplet, paths);

    if (const auto command_function = find_command(Commands::get_available_triplet_commands()))
    {
        return command_function->function->perform_and_exit(args, paths, default_triplet);
    }

    return invalid_command(args.command);
}

static void load_config(vcpkg::Files::Filesystem& fs)
{
    auto config = UserConfig::try_read_data(fs);

    bool write_config = false;

    // config file not found, could not be read, or invalid
    if (config.user_id.empty() || config.user_time.empty())
    {
        ::vcpkg::Metrics::Metrics::init_user_information(config.user_id, config.user_time);
        write_config = true;
    }

#if defined(_WIN32)
    if (config.user_mac.empty())
    {
        config.user_mac = Metrics::get_MAC_user();
        write_config = true;
    }
#endif

    {
        auto locked_metrics = Metrics::g_metrics.lock();
        locked_metrics->set_user_information(config.user_id, config.user_time);
#if defined(_WIN32)
        locked_metrics->track_property("user_mac", config.user_mac);
#endif
    }

    if (config.last_completed_survey.empty())
    {
        const auto now = Chrono::CTime::parse(config.user_time).value_or_exit(VCPKG_LINE_INFO);
        const Chrono::CTime offset = now.add_hours(-SURVEY_INITIAL_OFFSET_IN_HOURS);
        config.last_completed_survey = offset.to_string();
    }

    GlobalState::g_surveydate.lock()->assign(config.last_completed_survey);

    if (write_config)
    {
        config.try_write_data(fs);
    }
}

#if defined(_WIN32)
// note: this prevents a false positive for -Wmissing-prototypes on clang-cl
int wmain(int, const wchar_t* const* const);

#if !defined(_MSC_VER)
#include <shellapi.h>
int main(int argc, const char* const* const /*argv*/)
{
    wchar_t** wargv;
    wargv = CommandLineToArgvW(GetCommandLineW(), &argc);
    return wmain(argc, wargv);
}
#endif

int wmain(const int argc, const wchar_t* const* const argv)
#else
int main(const int argc, const char* const* const argv)
#endif
{
    if (argc == 0) std::abort();

    auto& fs = Files::get_real_filesystem();
    *GlobalState::timer.lock() = Chrono::ElapsedTimer::create_started();

#if defined(_WIN32)
    GlobalState::g_init_console_cp = GetConsoleCP();
    GlobalState::g_init_console_output_cp = GetConsoleOutputCP();
    GlobalState::g_init_console_initialized = true;

    SetConsoleCP(CP_UTF8);
    SetConsoleOutputCP(CP_UTF8);

    System::initialize_global_job_object();
#endif

    Checks::register_global_shutdown_handler([]() {
        const auto elapsed_us_inner = GlobalState::timer.lock()->microseconds();

        bool debugging = Debug::g_debugging;

        auto metrics = Metrics::g_metrics.lock();
        metrics->track_metric("elapsed_us", elapsed_us_inner);
        Debug::g_debugging = false;
        metrics->flush(Files::get_real_filesystem());

#if defined(_WIN32)
        if (GlobalState::g_init_console_initialized)
        {
            SetConsoleCP(GlobalState::g_init_console_cp);
            SetConsoleOutputCP(GlobalState::g_init_console_output_cp);
        }
#endif

        auto elapsed_us = GlobalState::timer.lock()->microseconds();
        if (debugging)
            System::printf("[DEBUG] Exiting after %d us (%d us)\n",
                           static_cast<int>(elapsed_us),
                           static_cast<int>(elapsed_us_inner));
    });

    {
        auto locked_metrics = Metrics::g_metrics.lock();
        locked_metrics->track_property("version", Commands::Version::version());
    }

    System::register_console_ctrl_handler();

    load_config(fs);

    VcpkgCmdArguments args = VcpkgCmdArguments::create_from_command_line(fs, argc, argv);
    args.imbue_from_environment();
    args.check_feature_flag_consistency();

    if (const auto p = args.disable_metrics.get()) Metrics::g_metrics.lock()->set_disabled(*p);
    if (const auto p = args.print_metrics.get()) Metrics::g_metrics.lock()->set_print_metrics(*p);
    if (const auto p = args.send_metrics.get()) Metrics::g_metrics.lock()->set_send_metrics(*p);
    if (const auto p = args.debug.get()) Debug::g_debugging = *p;

    if (args.send_metrics.has_value() && !Metrics::g_metrics.lock()->metrics_enabled())
    {
        System::print2(System::Color::warning,
                       "Warning: passed either --sendmetrics or --no-sendmetrics, but metrics are disabled.\n");
    }
    if (args.print_metrics.has_value() && !Metrics::g_metrics.lock()->metrics_enabled())
    {
        System::print2(System::Color::warning,
                       "Warning: passed either --printmetrics or --no-printmetrics, but metrics are disabled.\n");
    }

    args.debug_print_feature_flags();
    args.track_feature_flag_metrics();

    if (Debug::g_debugging)
    {
        inner(fs, args);
        Checks::exit_fail(VCPKG_LINE_INFO);
    }

    std::string exc_msg;
    try
    {
        inner(fs, args);
        Checks::exit_fail(VCPKG_LINE_INFO);
    }
    catch (std::exception& e)
    {
        exc_msg = e.what();
    }
    catch (...)
    {
        exc_msg = "unknown error(...)";
    }
    Metrics::g_metrics.lock()->track_property("error", exc_msg);

    fflush(stdout);
    System::printf("vcpkg.exe has crashed.\n"
                   "Please send an email to:\n"
                   "    %s\n"
                   "containing a brief summary of what you were trying to do and the following data blob:\n"
                   "\n"
                   "Version=%s\n"
                   "EXCEPTION='%s'\n"
                   "CMD=\n",
                   Commands::Contact::email(),
                   Commands::Version::version(),
                   exc_msg);
    fflush(stdout);
    for (int x = 0; x < argc; ++x)
    {
#if defined(_WIN32)
        System::print2(Strings::to_utf8(argv[x]), "|\n");
#else
        System::print2(argv[x], "|\n");
#endif
    }
    fflush(stdout);

    // It is expected that one of the sub-commands will exit cleanly before we get here.
    Checks::exit_fail(VCPKG_LINE_INFO);
}