v4l 0.13.1

use std::convert::TryFrom;
use std::fmt;

#[derive(Debug, Copy, Clone)]
#[repr(u32)]
/// Represents how fields are interlaced (if they are)
pub enum FieldOrder {
    /// Progressive, Top, Bottom, or Interlaced is acceptable; driver will pick one
    Any = 0,
    /// progressive, not interlaced
    Progressive = 1,
    /// top, or odd, field
    Top = 2,
    /// bottom, or even, field
    Bottom = 3,
    /// both fields interlaced
    Interlaced = 4,
    /// top field stored first, then bottom field
    SequentialTB = 5,
    /// bottom field stored first, then top field
    SequentialBT = 6,
    /// one field at a time, alternates between top and bottom
    Alternate = 7,
    /// both fields interlaced, starts with top
    InterlacedTB = 8,
    /// both fields interlaced, starts with bottom
    InterlacedBT = 9,
}

impl fmt::Display for FieldOrder {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::Any => write!(f, "any"),
            Self::Progressive => write!(f, "progressive"),
            Self::Top => write!(f, "top"),
            Self::Bottom => write!(f, "bottom"),
            Self::Interlaced => write!(f, "interlaced"),
            Self::SequentialTB => write!(f, "sequential, top then bottom"),
            Self::SequentialBT => write!(f, "sequential, bottom then top"),
            Self::Alternate => write!(f, "alternate between fields"),
            Self::InterlacedTB => write!(f, "interlaced, starting with top"),
            Self::InterlacedBT => write!(f, "interlaced, starting with bottom"),
        }
    }
}

impl TryFrom<u32> for FieldOrder {
    type Error = ();

    fn try_from(code: u32) -> Result<Self, Self::Error> {
        match code {
            0 => Ok(Self::Any),
            1 => Ok(Self::Progressive),
            2 => Ok(Self::Top),
            3 => Ok(Self::Bottom),
            4 => Ok(Self::Interlaced),
            5 => Ok(Self::SequentialTB),
            6 => Ok(Self::SequentialBT),
            7 => Ok(Self::Alternate),
            8 => Ok(Self::InterlacedTB),
            9 => Ok(Self::InterlacedBT),
            _ => Err(()),
        }
    }
}