Maraiah/src/marathon/wad.rs

117 lines
2.6 KiB
Rust

//! Marathon Wad format handling.
use std::collections::BTreeMap;
use std::fmt;
use durandal::bin::*;
use durandal::machead::try_mac_header;
use durandal::text::mac_roman_conv;
type Chunk <'a> = &'a[u8];
type ChunkMap<'a> = BTreeMap<Ident, Chunk<'a>>;
type EntryMap<'a> = BTreeMap<u16 , Entry<'a>>;
pub struct Entry<'a>
{
pub map: ChunkMap<'a>,
pub ext: &'a[u8],
}
#[derive(Debug)]
pub struct Wad<'a>
{
ver: Ver,
dvr: u16,
ext: usize,
nam: String,
pub ent: EntryMap<'a>,
}
#[derive(Debug)]
pub enum Ver
{
MI,
M2HasOvr,
M2HasDir,
M1
}
impl<'a> fmt::Debug for Entry<'a>
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result
{
write!(f, "Entry {{ ")?;
for (k, _) in &self.map {write!(f, "{} ", mac_roman_conv(&k[..]))?}
write!(f, "}}")
}
}
impl<'a> Wad<'a>
{
pub fn new(b: &[u8]) -> Wad
{
let b = &b[try_mac_header(b)..];
let ver = b_u16b(&b[ .. 2]);
let dvr = b_u16b(&b[ 2.. 4]);
let nam = &b[ 4..68];
// crc = b_u32b(&b[68..72]);
let dir = b_u32b(&b[72..76]) as usize;
let num = b_u16b(&b[76..78]) as usize;
let ext = b_u16b(&b[78..80]) as usize;
// hdr = b_u16b(&b[80..82]);
// bsz = b_u16b(&b[82..84]);
// pck = b_u32b(&b[84..88]);
let ver = match ver {
4 => Ver::MI,
2 => Ver::M2HasOvr,
1 => Ver::M2HasDir,
0 => panic!("old wad type unsupported"), //Ver::M1,
_ => panic!("invalid wad version"),
};
let mut map = EntryMap::new();
let mut p = dir;
let n = match ver {Ver::M1 | Ver::M2HasDir => true, _ => false};
let h = if n {8} else {10};
for i in 0..num
{
let ofs = b_u32b(&b[p ..p+ 4]) as usize;
let len = b_u32b(&b[p+4..p+ 8]) as usize;
let ind = if n {i as u16}
else {b_u16b(&b[p+8..p+10])};
let ent = Entry{map: get_chunks(&b[ofs..ofs+len]),
ext: &b[p+h..p+h+ext]};
map.insert(ind, ent);
p += h + ext;
}
Wad{ver, dvr, ext,
nam: mac_roman_conv(nam),
ent: map}
}
}
fn get_chunks(b: &[u8]) -> ChunkMap
{
let mut p = 0;
let mut map = ChunkMap::new();
while p < b.len()
{
let k = b_iden(&b[p ..p+ 4]);
// nx = b_u32b(&b[p+ 4..p+ 8]);
let l = b_u32b(&b[p+ 8..p+12]) as usize;
// o = b_u32b(&b[p+12..p+16]);
map.insert(k, &b[p+16..p+16+l]);
p += l + 16;
}
map
}
// EOF