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#include "qgstreamervideoinputdevicecontrol_p.h"

#include <QtCore/QDir>
#include <QtCore/QDebug>

#include <linux/types.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <sys/poll.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <linux/videodev2.h>

QGstreamerVideoInputDeviceControl::QGstreamerVideoInputDeviceControl(QObject *parent)
    :QVideoDeviceSelectorControl(parent), m_source(0), m_selectedDevice(0)
{
    update();
}

QGstreamerVideoInputDeviceControl::QGstreamerVideoInputDeviceControl(GstElement *source, QObject *parent)
    :QVideoDeviceSelectorControl(parent), m_source(source), m_selectedDevice(0)
{
    if (m_source)
        gst_object_ref(GST_OBJECT(m_source));

    update();
}

QGstreamerVideoInputDeviceControl::~QGstreamerVideoInputDeviceControl()
{
    if (m_source)
        gst_object_unref(GST_OBJECT(m_source));
}

int QGstreamerVideoInputDeviceControl::deviceCount() const
{
    return m_names.size();
}

QString QGstreamerVideoInputDeviceControl::deviceName(int index) const
{
    return m_names[index];
}

QString QGstreamerVideoInputDeviceControl::deviceDescription(int index) const
{
    return m_descriptions[index];
}

int QGstreamerVideoInputDeviceControl::defaultDevice() const
{
    return 0;
}

int QGstreamerVideoInputDeviceControl::selectedDevice() const
{
    return m_selectedDevice;
}


void QGstreamerVideoInputDeviceControl::setSelectedDevice(int index)
{
    if (index != m_selectedDevice) {
        m_selectedDevice = index;
        emit selectedDeviceChanged(index);
        emit selectedDeviceChanged(deviceName(index));
    }
}


void QGstreamerVideoInputDeviceControl::update()
{
    m_names.clear();
    m_descriptions.clear();

    // subdevsrc and the like have a camera-device property that takes an enumeration
    // identifying a primary or secondary camera, so return identifiers that map to those
    // instead of a list of actual devices.
    if (m_source && g_object_class_find_property(G_OBJECT_GET_CLASS(m_source), "camera-device")) {
        m_names << QLatin1String("primary") << QLatin1String("secondary");
        m_descriptions << tr("Main camera") << tr("Front camera");
        return;
    }

    QDir devDir("/dev");
    devDir.setFilter(QDir::System);

    QFileInfoList entries = devDir.entryInfoList(QStringList() << "video*");

    foreach( const QFileInfo &entryInfo, entries ) {
        //qDebug() << "Try" << entryInfo.filePath();

        int fd = ::open(entryInfo.filePath().toLatin1().constData(), O_RDWR );
        if (fd == -1)
            continue;

        bool isCamera = false;

        v4l2_input input;
        memset(&input, 0, sizeof(input));
        for (; ::ioctl(fd, VIDIOC_ENUMINPUT, &input) >= 0; ++input.index) {
            if(input.type == V4L2_INPUT_TYPE_CAMERA || input.type == 0) {
                isCamera = ::ioctl(fd, VIDIOC_S_INPUT, input.index) != 0;
                break;
            }
        }

        if (isCamera) {
            // find out its driver "name"
            QString name;
            struct v4l2_capability vcap;
            memset(&vcap, 0, sizeof(struct v4l2_capability));

            if (ioctl(fd, VIDIOC_QUERYCAP, &vcap) != 0)
                name = entryInfo.fileName();
            else
                name = QString((const char*)vcap.card);
            //qDebug() << "found camera: " << name;

            m_names.append(entryInfo.filePath());
            m_descriptions.append(name);
        }
        ::close(fd);
    }
}
