//! `Object` type.

use crate::{err::*, fixed::{Angle, Unit}};
use bitflags::bitflags;

/// Reads an `OBJS` chunk.
pub fn read(b: &[u8]) -> ResultS<(Object, usize)>
{
   read_data! {
      endian: BIG, buf: b, size: 16, start: 0, data {
         let group = u16[0];
         let index = u16[2];
         let angle = Angle[4];
         let poly  = u16[6];
         let pos_x = Unit[8];
         let pos_y = Unit[10];
         let pos_z = Unit[12];
         let flags = u16[14];
      }
   }

   let bias  = flags & 0xF0_00;
   let flags = flags & 0x0F_FF;
   let bias  = bias >> 12;
   let flags = flag_ok!(ObjectFlags, flags)?;

   Ok((Object{group, index, angle, poly, pos_x, pos_y, pos_z, flags, bias}, 16))
}

/// An object in the world.
#[cfg_attr(feature = "serde_obj", derive(serde::Serialize))]
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct Object
{
   pub group: u16,
   pub index: u16,
   pub angle: Angle,
   pub poly:  u16,
   pub pos_x: Unit,
   pub pos_y: Unit,
   pub pos_z: Unit,
   pub flags: ObjectFlags,
   pub bias:  u16,
}

bitflags! {
   /// Flags for `Object`.
   #[cfg_attr(feature = "serde_obj", derive(serde::Serialize))]
   pub struct ObjectFlags: u16
   {
      const INVISIBLE = 1;
      const CEILING   = 1 << 1;
      const BLIND     = 1 << 2;
      const DEAF      = 1 << 3;
      const FLOATING  = 1 << 4;
      const NET_ONLY  = 1 << 5;
   }
}

// EOF