// SPDX-License-Identifier: MPL-2.0
// Copyright © 2020 Skyline Team and Contributors (https://github.com/skyline-emu/)

#include <csignal>
#include <unistd.h>
#include "skyline/loader/loader.h"
#include "skyline/common.h"
#include "skyline/os.h"
#include "skyline/jvm.h"
#include "skyline/input.h"

bool Halt;
jobject Surface;
uint FaultCount;
skyline::GroupMutex JniMtx;
skyline::u16 fps;
skyline::u32 frametime;
std::weak_ptr<skyline::input::Input> inputWeak;

void signalHandler(int signal) {
    syslog(LOG_ERR, "Halting program due to signal: %s", strsignal(signal));
    if (FaultCount > 2)
        exit(SIGKILL);
    else
        Halt = true;
    FaultCount++;
}

extern "C" JNIEXPORT void Java_emu_skyline_EmulationActivity_executeApplication(JNIEnv *env, jobject instance, jstring romUriJstring, jint romType, jint romFd, jint preferenceFd, jstring appFilesPathJstring) {
    Halt = false;
    FaultCount = 0;
    fps = 0;
    frametime = 0;

    std::signal(SIGTERM, signalHandler);
    std::signal(SIGSEGV, signalHandler);
    std::signal(SIGINT, signalHandler);
    std::signal(SIGILL, signalHandler);
    std::signal(SIGABRT, signalHandler);
    std::signal(SIGFPE, signalHandler);

    setpriority(PRIO_PROCESS, static_cast<id_t>(gettid()), -8); // Set the priority of this process to the highest value

    auto jvmManager = std::make_shared<skyline::JvmManager>(env, instance);
    auto settings = std::make_shared<skyline::Settings>(preferenceFd);

    auto appFilesPath = env->GetStringUTFChars(appFilesPathJstring, nullptr);
    auto logger = std::make_shared<skyline::Logger>(std::string(appFilesPath) + "skyline.log", static_cast<skyline::Logger::LogLevel>(std::stoi(settings->GetString("log_level"))));
    //settings->List(logger); // (Uncomment when you want to print out all settings strings)

    auto start = std::chrono::steady_clock::now();

    try {
        skyline::kernel::OS os(jvmManager, logger, settings, std::string(appFilesPath));
        inputWeak = os.state.input;
        jvmManager->InitializeControllers();
        env->ReleaseStringUTFChars(appFilesPathJstring, appFilesPath);

        auto romUri = env->GetStringUTFChars(romUriJstring, nullptr);
        logger->Info("Launching ROM {}", romUri);
        env->ReleaseStringUTFChars(romUriJstring, romUri);

        os.Execute(romFd, static_cast<skyline::loader::RomFormat>(romType));
    } catch (std::exception &e) {
        logger->Error(e.what());
    } catch (...) {
        logger->Error("An unknown exception has occurred");
    }

    inputWeak.reset();

    logger->Info("Emulation has ended");

    auto end = std::chrono::steady_clock::now();
    logger->Info("Done in: {} ms", (std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count()));
}

extern "C" JNIEXPORT void Java_emu_skyline_EmulationActivity_setHalt(JNIEnv *, jobject, jboolean halt) {
    JniMtx.lock(skyline::GroupMutex::Group::Group2);
    Halt = halt;
    JniMtx.unlock();
}

extern "C" JNIEXPORT void Java_emu_skyline_EmulationActivity_setSurface(JNIEnv *env, jobject, jobject surface) {
    JniMtx.lock(skyline::GroupMutex::Group::Group2);
    if (!env->IsSameObject(Surface, nullptr))
        env->DeleteGlobalRef(Surface);
    if (!env->IsSameObject(surface, nullptr))
        Surface = env->NewGlobalRef(surface);
    else
        Surface = surface;
    JniMtx.unlock();
}

extern "C" JNIEXPORT jint Java_emu_skyline_EmulationActivity_getFps(JNIEnv *, jobject) {
    return fps;
}

extern "C" JNIEXPORT jfloat Java_emu_skyline_EmulationActivity_getFrametime(JNIEnv *, jobject) {
    return static_cast<float>(frametime) / 100;
}

extern "C" JNIEXPORT void JNICALL Java_emu_skyline_EmulationActivity_setController(JNIEnv *, jobject, jint index, jint type, jint partnerIndex) {
    auto input = inputWeak.lock();
    std::lock_guard guard(input->npad.mutex);
    input->npad.controllers[index] = skyline::input::GuestController{static_cast<skyline::input::NpadControllerType>(type), static_cast<skyline::i8>(partnerIndex)};
}

extern "C" JNIEXPORT void JNICALL Java_emu_skyline_EmulationActivity_updateControllers(JNIEnv *, jobject) {
    inputWeak.lock()->npad.Update();
}

extern "C" JNIEXPORT void JNICALL Java_emu_skyline_EmulationActivity_setButtonState(JNIEnv *, jobject, jint index, jlong mask, jboolean pressed) {
    try {
        auto input = inputWeak.lock();
        auto device = input->npad.controllers[index].device;
        if (device)
            device->SetButtonState(skyline::input::NpadButton{.raw = static_cast<skyline::u64>(mask)}, pressed);
    } catch (const std::bad_weak_ptr &) {
        // We don't mind if we miss button updates while input hasn't been initialized
    }
}

extern "C" JNIEXPORT void JNICALL Java_emu_skyline_EmulationActivity_setAxisValue(JNIEnv *, jobject, jint index, jint axis, jint value) {
    try {
        auto input = inputWeak.lock();
        auto device = input->npad.controllers[index].device;
        if (device)
            device->SetAxisValue(static_cast<skyline::input::NpadAxisId>(axis), value);
    } catch (const std::bad_weak_ptr &) {
        // We don't mind if we miss axis updates while input hasn't been initialized
    }
}

extern "C" JNIEXPORT void JNICALL Java_emu_skyline_EmulationActivity_setTouchState(JNIEnv *env, jobject, jintArray pointsJni) {
    try {
        using Point = skyline::input::TouchScreenPoint;

        auto input = inputWeak.lock();
        jboolean isCopy{false};

        std::span<Point> points(reinterpret_cast<Point *>(env->GetIntArrayElements(pointsJni, &isCopy)), env->GetArrayLength(pointsJni) / (sizeof(Point) / sizeof(jint)));
        input->touch.SetState(points);

        env->ReleaseIntArrayElements(pointsJni, reinterpret_cast<jint *>(points.data()), JNI_ABORT);
    } catch (const std::bad_weak_ptr &) {
        // We don't mind if we miss axis updates while input hasn't been initialized
    }
}