#include <chrono>
#include <csignal>
#include <errno.h>
#include <fcntl.h>
#include <fstream>
#include <iostream>
#include <iterator>
#include <linux/videodev2.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <thread>

#include "LibCamera.h"
#include "calibration.h"
#include "camera/veye_i2c.h"
#include "camera/veyeimx287m.h"
#include "dumps.h"
#include "fuck_intel.h"
#include "genetic_algos.h"
#include "imagealgos.h"
#include "laser.h"
#include "macro.h"
#include "protocols/httpserver.h"
// #include "pigpio.h"
#include "printerclient.h"
#include "profile.h"
#include "rotaryencoder.h"

#include <QCoreApplication>
#include <QDebug>
#include <QDir>
#include <QFile>
#include <QHttpServer>
#include <QImage>
#include <QJsonArray>
#include <QJsonDocument>
#include <QJsonObject>
#include <QSerialPort>
#include <QTextStream>
#include <QTimer>
#include <QtConcurrent/QtConcurrent>

#include "rapidjson/document.h"
#include "rapidjson/stringbuffer.h"
#include "rapidjson/writer.h"

extern uint8_t pgm_image[64 + img_width * img_height * sizeof(uint8_t)];
extern size_t pgm_image_size;
extern std::mutex pgm_image_mtx;

#define try_apply_config() \
    if (!applyConfig(config)) \
    { \
        camera->release(); \
        cm->stop(); \
\
        return EXIT_FAILURE; \
    }

ScanningModeFlags scanningModeFlags{ScanningModeFlags::None};

QElapsedTimer calibrationTimer;

extern volatile int32_t positionSteps;

requested_params_t requested_params;

namespace {
// std::shared_ptr<Image> img;
// Image *img = nullptr;
Pixels pixels;
std::vector<Pixels> calibrationPixels;
QMutex calibrationPixelsMutex;
} // namespace

using namespace std::chrono_literals;

// static std::shared_ptr<libcamera::Camera> camera;
// std::unique_ptr<libcamera::CameraConfiguration> config;
// static std::map<int, std::pair<void*, unsigned int>> mappedBuffers_;
// std::vector<std::unique_ptr<libcamera::Request>> requests;
libcamera::ControlList lastControls;

namespace {
CalibrationTablePtr calibrationTableZ;
CalibrationTablePtr calibrationTableX;
} // namespace

// static bool applyConfig(
//     const std::unique_ptr<libcamera::CameraConfiguration>& config
// );
// static void onRequestCompleted(libcamera::Request* completed_request);
// static void printControls();
// static QList<Pixels> filter(const QList<Pixels>& rawProfiles);

auto printPixels = [](const auto& pixels) {
    for (size_t i = (img_width - 10) / 2;
         i < img_width - ((img_width - 10) / 2);
         ++i)
    {
        std::cout << pixels[i] << " ";
    }
    std::cout << std::endl;
};

// void onNewImage(std::shared_ptr<Image> image)
// void onNewImage(Image &image)
// {
//     // std::cout << __func__ << std::endl << std::flush;

//     // if (!image)
//     // {
//     //     qDebug() << __func__ << "no image";
//     //     return;
//     // }

//     ::img = &image;
// }

void onNewPixels(std::shared_ptr<Pixels> pixels)
{
    // std::cout << __func__ << std::endl << std::flush;

    if (!pixels)
    {
        qDebug() << __func__ << "got null pixels";
    }

    if (!*pixels)
    {
        // qDebug() << __func__ << "got empty pixels";
    }

    // for (size_t i = 640 - 5; i < 640 + 5; i++)
    // {
    //     // std::cout << pixels->pixels[i] << " ";
    // }

    // std::cout << std::endl

    ::pixels = *pixels;
}

bool initLaser();

bool initCam();

int main(int argc, char* argv[])
{
    auto sigHandler = [](int s) {
        std::cout << "got signal " << s << std::endl;
        std::signal(s, SIG_DFL);
        // QTimer::singleShot(0, qApp, &QCoreApplication::quit);
        // qApp->quit();
    };

    // if (!initCam()) {
    //     return EXIT_FAILURE;
    // }

    // return EXIT_SUCCESS;

    // for (int i = 2000; i >= 0; i -= 50) {
    // for (int i = 0; i < 2000; i += 50) {
    //     if (!veye::imx287m::test(i)) {
    //         return EXIT_FAILURE;
    //     }
    // }
    // return EXIT_SUCCESS;

    std::signal(SIGINT, sigHandler);
    std::signal(SIGTERM, sigHandler);

    QCoreApplication app(argc, argv);
    // QTimer::singleShot(4000, qApp, &QCoreApplication::quit);

    QList<QFuture<void>> initializers;

    // if (false)
    qDebug() << "size of raw profile" << sizeof(Pixels);
    if (false) {
        // open binary calibration table
        if (true)
        {
            initializers << QtConcurrent::run([&]() {
                if (!openCalibrationTable("/home/user/dumps/binz.calibration_table",
                                          // "/tmp/binz.calibration_table",
                                          ::calibrationTableZ)) {
                    exit(EXIT_FAILURE);
                }
            });

            initializers << QtConcurrent::run([&]() {
                if (!openCalibrationTable("/home/user/dumps/binx.calibration_table",
                                          // "/tmp/binx.calibration_table",
                                          ::calibrationTableX)) {
                    exit(EXIT_FAILURE);
                }
            });
        }

        if (false)
        {
            // z
            // if (!openCalibrationTable(
            //         "/home/user/dumps/binz.calibration_table",
            //         ::calibrationTableZ
            //     ))
            // {
            //     exit(EXIT_FAILURE);
            // }

            // if (!calibrationTableToImage(::calibrationTableZ)
            //          .save("/home/user/dumps/imageZ.png"))
            // {
            //     qDebug() << "cannot save imageZ.png";
            //     exit(EXIT_FAILURE);
            // }

            // interpolate(::calibrationTableZ);
            // exit(EXIT_SUCCESS);

            // calibrationTableToImage(::calibrationTableZ)
            //     .save("/home/user/dumps/imageZ_interpolated.png");

            auto rawProfiles = openDump("/home/user/dumps/binx");
            qDebug() << "raw x-profiles count is" << rawProfiles.size();
            // qDebug() << "height" << calibrationColumnHeight;

            auto filteredRawProfiles = filter(std::move(rawProfiles));
            qDebug() << "filtered x-profiles count is"
                     << filteredRawProfiles.count();

            ::calibrationTableX = calibrateX(std::move(filteredRawProfiles));

            // for (size_t i = 9471; i < 9472; i++) {
            //     std::cout << "row #" << i << ": ";

            //     for (size_t j = 0; j < 1280; ++j) {
            //         const auto& p = ::calibrationTableX->at(j).at(i);
            //         std::cout << p << ' ';
            //     }

            //     std::cout << std::endl;
            // }

            // x
            // qDebug() << "open x table";
            // if (!openCalibrationTable("/home/user/dumps/binx.calibration_table",
            //                           ::calibrationTableX)) {
            //     exit(EXIT_FAILURE);
            // }

            // if (!calibrationTableToImage(::calibrationTableX)
            //          .save("/home/user/dumps/imageX.png")) {
            //     qDebug() << "cannot save imageX.png";
            //     exit(EXIT_FAILURE);
            // }

            // for (size_t i = 9471; i < 9472; i++) {
            //     std::cout << "row #" << i << ": ";

            //     for (size_t j = 0; j < 1280; ++j) {
            //         const auto& p = ::calibrationTableX->at(j).at(i);
            //         std::cout << p << ' ';
            //     }

            //     std::cout << std::endl;
            // }

            // exit(EXIT_SUCCESS);
            interpolate(::calibrationTableX);

            // calibrationTableToImage(::calibrationTableX)
            //     .save("/home/user/dumps/imageX_interpolated.png");
        }

        // load binary calibration dumps and calibrate
        if (false)
        {
            if (true)
            {
                auto rawProfiles = openDump("/home/user/dumps/binz");
                // auto rawProfiles = openDump("/home/user/dumps/z");
                qDebug() << "raw z-profiles count is" << rawProfiles.size();
                // qDebug() << "height" << calibrationColumnHeight;

                auto filteredRawProfiles = filter(std::move(rawProfiles));
                qDebug() << "filtered z-profiles count is"
                         << filteredRawProfiles.count();

                ::calibrationTableZ = calibrateZ(std::move(filteredRawProfiles),
                                                 requested_params.stepsPerMm);

                // bool ok = calibrationTableToImage(::calibrationTableZ)
                //               .save("/home/user/dumps/z/imageZ.png");

                // if (!ok)
                // {
                //     qDebug() << "cannot save imageZ.png";
                //     exit(EXIT_FAILURE);
                // }

                interpolate(::calibrationTableZ);

                if (!dump(::calibrationTableZ,
                          "/home/user/dumps/binz.calibration_table"))
                {
                    qApp->exit(EXIT_FAILURE);
                }
                // calibrationTableToImage(::calibrationTableZ)
                //     .save("/home/user/dumps/z/imageZ_interpolated.png");
                // exit(EXIT_SUCCESS);
            }

            qDebug()
                << "--------------------------------------------------------";

            if (true)
            {
                auto rawProfiles = openDump("/home/user/dumps/binx");
                qDebug() << "raw x-profiles count is" << rawProfiles.size();
                // qDebug() << "height" << calibrationColumnHeight;

                auto filteredRawProfiles = filter(std::move(rawProfiles));
                qDebug() << "filtered x-profiles count is"
                         << filteredRawProfiles.count();

                ::calibrationTableX = calibrateX(std::move(filteredRawProfiles));

                // bool ok = calibrationTableToImage(::calibrationTableX)
                //               .save("/home/user/dumps/z/imageX.png");

                // if (!ok)
                // {
                //     qDebug() << "cannot save imageX.png";
                //     exit(EXIT_FAILURE);
                // }

                interpolate(::calibrationTableX);

                if (!dump(::calibrationTableX,
                          "/home/user/dumps/binx.calibration_table"))
                {
                    qApp->exit(EXIT_FAILURE);
                }

                // calibrationTableToImage(::calibrationTableX)
                //     .save("/home/user/dumps/z/imageX_interpolated.png");
            }
        }
    }

    // exit(EXIT_SUCCESS);

    // if (!initLaser()) {
    //     return EXIT_FAILURE;
    // }

    // PrinterClient printerClient;

    QElapsedTimer t;
    t.start();

    qDebug() << "msecs before encoder:" << t.elapsed();

    // RotaryEncoder encoder;

    qDebug() << "msecs before camera:" << t.elapsed();
    // FIXME: don't use one var for everything
    int ret;
    // const auto cameras = cm->cameras();
    // const auto cameras = OV9281::search(cm);
    // const auto cameras = InnoMakerOV9281::search();
    const auto cameras = VeyeIMX287m::search();
    // const auto cameras =

    if (cameras.empty())
    {
        std::cerr << "No cameras were identified on the system." << std::endl;

        return EXIT_FAILURE;
    }

    auto camera = cameras.at(0);

    std::cout << "connect everything" << std::endl;
    // camera->newPixels.connect(&onNewPixels);
    // camera->newImage.connect(&onNewImage);
    // camera->newImageCallback = &onNewImage;
    camera->newPixelsCallback = &onNewPixels;

    for (auto& i : initializers)
        i.waitForFinished();
    std::cout << "loaded calibration tables" << std::endl;

    if (!camera->startStream())
    {
        return EXIT_FAILURE;
    }

    QHttpServer qHttpServer;
    auto httpGetImage = [&]() -> QHttpServerResponse {
        auto cam = dynamic_cast<VeyeIMX287m *>(camera.get());

        if (!cam) {
            qDebug() << "NO CAM";
            return QHttpServerResponse::StatusCode::ServiceUnavailable;
        }

        static Image img;

        if (!cam->getImage(img)) {
            qDebug() << "cannot get image";
            return QHttpServerResponse::StatusCode::ServiceUnavailable;
        }

        pgm_save(&img);
        std::lock_guard<std::mutex> lg(pgm_image_mtx);

        return QHttpServerResponse{QByteArray((const char *) pgm_image, pgm_image_size),
                                   QHttpServerResponse::StatusCode::Ok};
    };
    qHttpServer.route("/v1/sensor/image", httpGetImage);
    qHttpServer.route("/v1/sensor/image2", httpGetImage);

    qHttpServer.route("/v1/pixels", [&]() -> QHttpServerResponse {
        // std::cout << "http: pixels" << std::endl;
        // return QHttpServerResponse::StatusCode::ServiceUnavailable;

        auto cam = dynamic_cast<VeyeIMX287m *>(camera.get());

        if (!cam) {
            qDebug() << "NO CAM";
            return QHttpServerResponse::StatusCode::ServiceUnavailable;
        }

        Image img;
        // yeaah
        // ::img = &img;
        if (!cam->getImage(img)) {
            qDebug() << "cannot get image";
            return QHttpServerResponse::StatusCode::ServiceUnavailable;
        }

        ::pixels = std::move(img.pixels());
        ++cam->processedCounter;

        // qt json does not allow to limit double precision
        const auto lines = pixelsToLines(::pixels);

        const auto nan2zero = [](const auto &value) { return qIsNaN(value) ? 0 : value; };
        rapidjson::Document jd;
        jd.SetObject();
        auto &al = jd.GetAllocator();

        rapidjson::Value rjPixels{rapidjson::kArrayType};

        for (size_t i = 0; i < img_width; ++i) {
            rjPixels.PushBack(nan2zero(::pixels.pixels[i]), al);
        }

        rapidjson::Value rjLines{rapidjson::kArrayType};

        for (const auto &l : lines) {
            rapidjson::Value rjLineP1{rapidjson::kArrayType};
            rjLineP1.PushBack(nan2zero(l.p1().x()), al).PushBack(nan2zero(l.p1().y()), al);
            rapidjson::Value rjLineP2{rapidjson::kArrayType};
            rjLineP2.PushBack(nan2zero(l.p2().x()), al).PushBack(nan2zero(l.p2().y()), al);
            rapidjson::Value rjLinePoints{rapidjson::kArrayType};
            rjLinePoints.PushBack(rjLineP1, al).PushBack(rjLineP2, al);

            rjLines.PushBack(rjLinePoints, al);
        }

        // jd.AddMember("encoderPosition", qint64{encoder.position()});
        // FIXME: get prom pixels struct
        jd.AddMember("measurementCounter", img.counters.measurementCounter, al);
        jd.AddMember("timestampUs", img.counters.timestampUs, al);
        jd.AddMember("pixels", rjPixels.Move(), al);
        jd.AddMember("lines", rjLines.Move(), al);

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        writer.SetMaxDecimalPlaces(2);
        jd.Accept(writer);
        QString res{(const char *) buffer.GetString()};
        // qDebug() << "size:" << res.size();
        // qDebug().noquote() << "ret pix";

        return QHttpServerResponse{res};
    });

    qHttpServer.route("/v1/profile", [&]() -> QHttpServerResponse {
        // std::cout << "http: profile" << std::endl;
        return QHttpServerResponse::StatusCode::ServiceUnavailable;
        std::lock_guard<std::mutex> lg(pgm_image_mtx);

        if (!::calibrationTableZ || !::calibrationTableX)
            return QHttpServerResponse::StatusCode::ServiceUnavailable;

        const Profile profile(::pixels,
                              ::calibrationTableZ,
                              ::calibrationTableX);

        const QJsonObject json{{"profile", QJsonObject(profile)}};

        return QHttpServerResponse(QJsonDocument(json).toJson());
    });

    qHttpServer
        .route("/v1/commands/resetEncoder",
               [&](const QHttpServerRequest& request) -> QHttpServerResponse {
                   std::cout << "http: resetEncoder" << std::endl;
                   if (request.method() != QHttpServerRequest::Method::Post)
                   {
                       return QHttpServerResponse::StatusCode::NotFound;
                   }

                   qDebug() << "reset encoder";

                   positionSteps = 0;

                   return QHttpServerResponse::StatusCode::Ok;
               });

    qHttpServer
        .route("/v1/commands/startCalibration",
               [&](const QHttpServerRequest& request) -> QHttpServerResponse {
                   std::cout << "http: startCalibration" << std::endl;
                   if (request.method() != QHttpServerRequest::Method::Post)
                   {
                       return QHttpServerResponse::StatusCode::NotFound;
                   }

                   qDebug() << "start calibration";

                   // TODO: use flags
                   scanningModeFlags = ScanningModeFlags::Calibration;
                   calibrationTimer.start();

                   return QHttpServerResponse::StatusCode::Ok;
               });

    qHttpServer.route("/v1/commands/gCode",
                      [&](const QHttpServerRequest &request) -> QHttpServerResponse {
                          std::cout << "http: gCode" << std::endl;
                          if (request.method() != QHttpServerRequest::Method::Post) {
                              return QHttpServerResponse::StatusCode::NotFound;
                          }

                          const auto command = request.body();

                          qDebug() << "send gCode:" << command;

                          // printerClient.sendCommand(command);

                          return QHttpServerResponse::StatusCode::Ok;
                      });

    qHttpServer.route(
        "/v1/sensor/params",
        [&](const QHttpServerRequest& request) -> QHttpServerResponse {
            // std::cout << "http: params" << std::endl;
            switch (request.method())
            {
            case QHttpServerRequest::Method::Get: {
                std::lock_guard<std::mutex> lg(pgm_image_mtx);
                QJsonObject json;

                return QHttpServerResponse(QJsonDocument(json).toJson());
            }

            case QHttpServerRequest::Method::Post: {
                // qDebug() << "request body:" << request.body();

                auto json = QJsonDocument::fromJson(request.body()).object();

                if (json.contains(exposureTimeKey))
                {
                    const int32_t value{json[exposureTimeKey].toInt()};

                    if (value == 0)
                        return QHttpServerResponse::StatusCode::
                            RequestRangeNotSatisfiable;

                    // qDebug() << "set new exposure time:" << value;

                    // requested_params.exposureTime = value;
                    if (!camera->set_exposureTime(
                            std::chrono::microseconds(value))) {
                        qDebug() << "cannot set exp";
                        return QHttpServerResponse::StatusCode::
                            RequestRangeNotSatisfiable;
                    }
                }

                if (json.contains(gainKey))
                {
                    const auto value = json[gainKey].toDouble();

                    if (value == 0)
                        return QHttpServerResponse::StatusCode::
                            RequestRangeNotSatisfiable;

                    if (!camera->set_gain(value))
                        return QHttpServerResponse::StatusCode::
                            RequestRangeNotSatisfiable;
                }

                if (json.contains(laserLevelKey))
                {
                    const int32_t value{json[laserLevelKey].toInt()};

                    if (!camera->setLaserLevel(value))
                        return QHttpServerResponse::StatusCode::
                            RequestRangeNotSatisfiable;

                    requested_params.laserLevel = value;
                }

                return QHttpServerResponse(request.body());
            }
            default: {
                return QHttpServerResponse(
                    QByteArray("unsupported http method"));
            }
            }
        });

    qDebug() << "listen: " << qHttpServer.listen(QHostAddress::Any, 8081);

    ////////////////////////////////////////////////////////////////////////////
    std::clog << std::flush;
    std::cerr << std::flush;
    std::cout << "ok for now" << std::endl << std::flush;

    auto result = app.exec();

    return result;
}

bool initLaser()
{
    const QLatin1String pwmChip{"pwmchip2"};
    const uint16_t pwmChannel{1};
    const QLatin1String pwmSystemRoot{"/sys/class/pwm"};
    const QString pwmChipRoot{pwmSystemRoot + "/" + pwmChip};

    const QString pwmExportFile{pwmChipRoot + "/export"};

    QFile f{pwmExportFile};

    if (!f.open(QFile::WriteOnly))
    {
        qWarning() << "cannot open" << f.fileName() << "for writing";
        qWarning() << "error:" << f.errorString();

        return false;
    }

    QTextStream s{&f};
    s << pwmChannel;

    const QString pwm{QLatin1String("pwm%1").arg(QString::number(pwmChannel))};
    const QString pwmRoot{pwmChipRoot + "/" + pwm};

    const QString periodFilename{pwmRoot + "/period"};
    f.close();
    f.setFileName(periodFilename);

    if (!f.open(QFile::WriteOnly))
    {
        qWarning() << "cannot open" << f.fileName() << "for writing";
        qWarning() << "error:" << f.errorString();

        return false;
    }

    const unsigned periodHz{50'000};

    s << periodHz;

    const QString dutyCycleFilename{pwmRoot + "/duty_cycle"};
    f.close();
    f.setFileName(dutyCycleFilename);

    if (!f.open(QFile::WriteOnly))
    {
        qWarning() << "cannot open" << f.fileName() << "for writing";
        qWarning() << "error:" << f.errorString();

        return false;
    }

    const unsigned dutyCycle{3'000};

    s << dutyCycle;

    const QString enableFilename{pwmRoot + "/enable"};
    f.close();
    f.setFileName(enableFilename);

    if (!f.open(QFile::WriteOnly))
    {
        qWarning() << "cannot open" << f.fileName() << "for writing";
        qWarning() << "error:" << f.errorString();

        return false;
    }

    const int enable{1};

    s << enable;

    return true;
}

bool initCam()
{
    const v4l2_memory memtype = V4L2_MEMORY_MMAP;
    v4l2_buf_type type = (enum v4l2_buf_type) - 1;
    const char *devname{"/dev/video0"};
    int fd{open(devname, O_RDWR)};

    if (fd < 0) {
        printf("Error opening device %s: %s (%d).\n", devname, strerror(errno), errno);
        fflush(stdout);
        return false;
    }

    std::cout << devname << ": opened" << std::endl;

    v4l2_capability cap;
    memset(&cap, 0, sizeof cap);
    const auto ret = ioctl(fd, VIDIOC_QUERYCAP, &cap);
    if (ret < 0) {
        printf("cannot query cap for %s: %s (%d).\n", devname, strerror(errno), errno);
        fflush(stdout);
        return false;
    }

    std::cout << devname << ": got caps" << std::endl;

    const auto caps = cap.capabilities & V4L2_CAP_DEVICE_CAPS ? cap.device_caps : cap.capabilities;
    const bool has_video = caps
                           & (V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_CAPTURE
                              | V4L2_CAP_VIDEO_OUTPUT_MPLANE | V4L2_CAP_VIDEO_OUTPUT);
    const bool has_meta = caps & (V4L2_CAP_META_CAPTURE | V4L2_CAP_META_OUTPUT);
    const bool has_capture = caps
                             & (V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_CAPTURE
                                | V4L2_CAP_META_CAPTURE);
    const bool has_output = caps
                            & (V4L2_CAP_VIDEO_OUTPUT_MPLANE | V4L2_CAP_VIDEO_OUTPUT
                               | V4L2_CAP_META_OUTPUT);
    const bool has_mplane = caps & (V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_OUTPUT_MPLANE);

    printf("Device `%s' on `%s' (driver '%s') supports%s%s%s%s %s mplanes.\n",
           cap.card,
           cap.bus_info,
           cap.driver,
           has_video ? " video," : "",
           has_meta ? " meta-data," : "",
           has_capture ? " capture," : "",
           has_output ? " output," : "",
           has_mplane ? "with" : "without");

    const auto buf_type = [caps, devname]() -> int {
        if (caps & V4L2_CAP_VIDEO_CAPTURE_MPLANE) {
            std::cout << devname << ": buf_type: V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE" << std::endl;
            return V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
        } else if (caps & V4L2_CAP_VIDEO_OUTPUT_MPLANE) {
            std::cout << devname << ": buf_type: V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE" << std::endl;
            return V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
        } else if (caps & V4L2_CAP_VIDEO_CAPTURE) {
            std::cout << devname << ": buf_type: V4L2_BUF_TYPE_VIDEO_CAPTURE" << std::endl;
            return V4L2_BUF_TYPE_VIDEO_CAPTURE;
        } else if (caps & V4L2_CAP_VIDEO_OUTPUT) {
            std::cout << devname << ": buf_type: V4L2_BUF_TYPE_VIDEO_OUTPUT" << std::endl;
            return V4L2_BUF_TYPE_VIDEO_OUTPUT;
        } else if (caps & V4L2_CAP_META_CAPTURE) {
            std::cout << devname << ": buf_type: V4L2_BUF_TYPE_META_CAPTURE" << std::endl;
            return V4L2_BUF_TYPE_META_CAPTURE;
        } else if (caps & V4L2_CAP_META_OUTPUT) {
            std::cout << devname << ": buf_type: V4L2_BUF_TYPE_META_OUTPUT" << std::endl;
            return V4L2_BUF_TYPE_META_OUTPUT;
        } else {
            printf("Device supports neither capture nor output.\n");
            return -EINVAL;
        }
    }();

    if (buf_type < 0) {
        return false;
    }

    if (false) {
        v4l2_format fmt;
        memset(&fmt, 0, sizeof fmt);
        fmt.type = buf_type;

        if (ioctl(fd, VIDIOC_G_FMT, &fmt) < 0) {
            printf("Unable to get format: %s (%d).\n", strerror(errno), errno);

            return false;
        }

        const auto width = fmt.fmt.pix_mp.width;
        const auto height = fmt.fmt.pix_mp.height;
        const auto num_planes = fmt.fmt.pix_mp.num_planes;
        struct v4l2_plane_pix_format plane_fmt[VIDEO_MAX_PLANES] = {0};

        printf("Video format: (%08x) %ux%u field %d, %u planes: \n",
               fmt.fmt.pix_mp.pixelformat,
               fmt.fmt.pix_mp.width,
               fmt.fmt.pix_mp.height,
               fmt.fmt.pix_mp.field,
               fmt.fmt.pix_mp.num_planes);

        for (int i = 0; i < fmt.fmt.pix_mp.num_planes; i++) {
            plane_fmt[i].bytesperline = fmt.fmt.pix_mp.plane_fmt[i].bytesperline;
            plane_fmt[i].sizeimage = fmt.fmt.pix_mp.plane_fmt[i].bytesperline
                                         ? fmt.fmt.pix_mp.plane_fmt[i].sizeimage
                                         : 0;

            printf(" * Stride %u, buffer size %u\n",
                   fmt.fmt.pix_mp.plane_fmt[i].bytesperline,
                   fmt.fmt.pix_mp.plane_fmt[i].sizeimage);
        }
    }

    unsigned int padding = 0;
    unsigned int nbufs = 8;

    // if ()

    close(fd);

    return true;
}