//! `Light` type.

use crate::{durandal::{bin::OptU16, err::*, fixed::{Angle, Fixed, Unit}},
            marathon::xfer::TransferMode};
use super::pnts;

/// Reads a `medi` chunk.
pub fn read(b: &[u8]) -> ResultS<(Media, usize)>
{
   read_data! {
      endian: BIG, buf: b, size: 32, start: 0, data {
         let mtype   = u16[0] enum MediaType;
         let flags   = u16[2];
         let control = u16[4];
         let dir     = Angle[6];
         let mag     = Unit[8];
         let hei_lo  = Unit[10];
         let hei_hi  = Unit[12];
         let orig    = pnts::read_o[14; 4];
         let hei_nrm = Unit[18];
         let min_lt  = Fixed[20];
         let texture = OptU16[24];
         let xfer    = u16[26] enum TransferMode;
      }
   }

   let flr_obs = flags != 0;

   Ok((Media{mtype, flr_obs, control, dir, mag, hei_lo, hei_hi, orig, hei_nrm,
             min_lt, texture, xfer}, 32))
}

/// A media, as in a part of a polygon which goes up the middle of the wall.
#[cfg_attr(feature = "serde_obj", derive(serde::Serialize))]
#[derive(Debug, Eq, PartialEq)]
pub struct Media
{
   pub mtype:   MediaType,
   pub flr_obs: bool,
   pub control: u16,
   pub dir:     Angle,
   pub mag:     Unit,
   pub hei_lo:  Unit,
   pub hei_hi:  Unit,
   pub orig:    pnts::Point,
   pub hei_nrm: Unit,
   pub min_lt:  Fixed,
   pub texture: OptU16,
   pub xfer:    TransferMode,
}

c_enum! {
   /// The liquid type of a `Media`.
   #[cfg_attr(feature = "serde_obj", derive(serde::Serialize))]
   #[derive(Debug)]
   pub enum MediaType: u16
   {
      Water  = 0,
      Lava   = 1,
      Goo    = 2,
      Sewage = 3,
   }
}

// EOF