/*
 *******************************************************************************
 *                                   INCLUDE
 *******************************************************************************
 */
#include "InputFormat.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/videodev2.h>
#include <Poco/Exception.h>
#include <Poco/Format.h>

namespace Video
{
namespace V4L2
{
/*
 *******************************************************************************
 *                                CLASS DEFINE
 *******************************************************************************
 */
void InputFormat::enumerate(const std::string& deviceName, InputFormat::Collection& c)
{
    int fd = open(deviceName.c_str(), O_RDWR);
    if (fd < 0)
        throw Poco::InvalidAccessException(Poco::format("Video::V4l2::InputFormat: Open %s FAIL: %d", deviceName, fd));

    struct v4l2_fmtdesc fmt;
    fmt.type  = V4L2_BUF_TYPE_VIDEO_CAPTURE;
    fmt.index = 0;
    while (ioctl(fd, VIDIOC_ENUM_FMT, &fmt) == 0)
    {
        InputFormat format;
        format.pixelFormat = fmt.pixelformat;
        format.description = (char*)fmt.description;

        struct v4l2_frmsizeenum frmsize;
        frmsize.index        = 0;
        frmsize.pixel_format = fmt.pixelformat;
        while (ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &frmsize) == 0)
        {
            switch (frmsize.type)
            {
            case V4L2_FRMSIZE_TYPE_DISCRETE:
            {
                struct v4l2_frmivalenum frameinterval;

                frameinterval.width        = frmsize.discrete.width;
                frameinterval.height       = frmsize.discrete.height;
                frameinterval.pixel_format = fmt.pixelformat;
                frameinterval.type         = V4L2_FRMIVAL_TYPE_DISCRETE;
                frameinterval.index        = 0;
                while (ioctl(fd, VIDIOC_ENUM_FRAMEINTERVALS, &frameinterval) == 0)
                {
                    InputFormat::Resolution resolution;
                    resolution.width  = frameinterval.width;
                    resolution.height = frameinterval.height;
                    resolution.fps    = frameinterval.discrete.denominator / frameinterval.discrete.numerator;
                    format.resolutions.push_back(resolution);

                    frameinterval.index++;
                }
            }
            break;
            }

            frmsize.index++;
        }

        format.resolutions.sort([](auto& a, auto& b) { return a.width * a.height > b.width * b.height; });

        c.push_back(format);
        fmt.index++;
    }

    close(fd);
}
}
}