// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include "common/assert.h"
#include "common/common_types.h"
#include "common/file_util.h"

#include "core/core.h"
#include "core/loader/loader.h"
#include "core/settings.h"
#include "core/telemetry_session.h"

namespace Core {

static u64 GenerateTelemetryId() {
    u64 telemetry_id{};
    return telemetry_id;
}

u64 GetTelemetryId() {
    u64 telemetry_id{};
    const std::string filename{FileUtil::GetUserPath(FileUtil::UserPath::ConfigDir) +
                               "telemetry_id"};

    if (FileUtil::Exists(filename)) {
        FileUtil::IOFile file(filename, "rb");
        if (!file.IsOpen()) {
            LOG_ERROR(Core, "failed to open telemetry_id: {}", filename);
            return {};
        }
        file.ReadBytes(&telemetry_id, sizeof(u64));
    } else {
        FileUtil::IOFile file(filename, "wb");
        if (!file.IsOpen()) {
            LOG_ERROR(Core, "failed to open telemetry_id: {}", filename);
            return {};
        }
        telemetry_id = GenerateTelemetryId();
        file.WriteBytes(&telemetry_id, sizeof(u64));
    }

    return telemetry_id;
}

u64 RegenerateTelemetryId() {
    const u64 new_telemetry_id{GenerateTelemetryId()};
    const std::string filename{FileUtil::GetUserPath(FileUtil::UserPath::ConfigDir) +
                               "telemetry_id"};

    FileUtil::IOFile file(filename, "wb");
    if (!file.IsOpen()) {
        LOG_ERROR(Core, "failed to open telemetry_id: {}", filename);
        return {};
    }
    file.WriteBytes(&new_telemetry_id, sizeof(u64));
    return new_telemetry_id;
}

std::future<bool> VerifyLogin(std::string username, std::string token, std::function<void()> func) {
#ifdef ENABLE_WEB_SERVICE
    return WebService::VerifyLogin(username, token, Settings::values.verify_endpoint_url, func);
#else
    return std::async(std::launch::async, [func{std::move(func)}]() {
        func();
        return false;
    });
#endif
}

TelemetrySession::TelemetrySession() {
#ifdef ENABLE_WEB_SERVICE
    if (Settings::values.enable_telemetry) {
        backend = std::make_unique<WebService::TelemetryJson>(
            Settings::values.telemetry_endpoint_url, Settings::values.yuzu_username,
            Settings::values.yuzu_token);
    } else {
        backend = std::make_unique<Telemetry::NullVisitor>();
    }
#else
    backend = std::make_unique<Telemetry::NullVisitor>();
#endif
    // Log one-time top-level information
    AddField(Telemetry::FieldType::None, "TelemetryId", GetTelemetryId());

    // Log one-time session start information
    const s64 init_time{std::chrono::duration_cast<std::chrono::milliseconds>(
                            std::chrono::system_clock::now().time_since_epoch())
                            .count()};
    AddField(Telemetry::FieldType::Session, "Init_Time", init_time);
    std::string program_name;
    const Loader::ResultStatus res{System::GetInstance().GetAppLoader().ReadTitle(program_name)};
    if (res == Loader::ResultStatus::Success) {
        AddField(Telemetry::FieldType::Session, "ProgramName", program_name);
    }

    // Log application information
    Telemetry::AppendBuildInfo(field_collection);

    // Log user system information
    Telemetry::AppendCPUInfo(field_collection);
    Telemetry::AppendOSInfo(field_collection);

    // Log user configuration information
    AddField(Telemetry::FieldType::UserConfig, "Core_UseCpuJit", Settings::values.use_cpu_jit);
    AddField(Telemetry::FieldType::UserConfig, "Core_UseMultiCore",
             Settings::values.use_multi_core);
    AddField(Telemetry::FieldType::UserConfig, "Renderer_ResolutionFactor",
             Settings::values.resolution_factor);
    AddField(Telemetry::FieldType::UserConfig, "Renderer_UseFrameLimit",
             Settings::values.use_frame_limit);
    AddField(Telemetry::FieldType::UserConfig, "Renderer_FrameLimit", Settings::values.frame_limit);
    AddField(Telemetry::FieldType::UserConfig, "Renderer_UseAccurateFramebuffers",
             Settings::values.use_accurate_framebuffers);
    AddField(Telemetry::FieldType::UserConfig, "System_UseDockedMode",
             Settings::values.use_docked_mode);
}

TelemetrySession::~TelemetrySession() {
    // Log one-time session end information
    const s64 shutdown_time{std::chrono::duration_cast<std::chrono::milliseconds>(
                                std::chrono::system_clock::now().time_since_epoch())
                                .count()};
    AddField(Telemetry::FieldType::Session, "Shutdown_Time", shutdown_time);

    // Complete the session, submitting to web service if necessary
    // This is just a placeholder to wrap up the session once the core completes and this is
    // destroyed. This will be moved elsewhere once we are actually doing real I/O with the service.
    field_collection.Accept(*backend);
    backend->Complete();
    backend = nullptr;
}

} // namespace Core