#!/usr/bin/env bash
# Gera o blasphemer.wad servido no fredygames.com a partir do release 0.1.8 do Blasphemer (BSD-3-Clause,
# https://github.com/Blasphemer/blasphemer/releases/tag/v0.1.8, blasphem-0.1.8.zip), com tres mudancas
# nossas no IWAD (o resto dos lumps sai byte a byte igual):
#   - tira as fases dos episodios 4 e 5 (E4M1-E5M9) e do episodio 6 (E6M1-E6M3): o 4 so tem fases de
#     deathmatch, o 5 e o 6 sao quartos em branco ("PLACE HOLDER" no wadinfo.txt do projeto), e o lump
#     EXTENDED (que faz o motor oferecer cinco episodios): o jogo fica com os tres episodios completos;
#   - troca o GENMIDI (instrumentos do chip OPL, que o proprio projeto marca como "PLACE HOLDER" e que veio
#     de um import de 2010 sem origem registrada) pelo do Freedoom 0.13.0, tambem BSD-3-Clause (instrumentos
#     de Matt Cadirao, nos CREDITS do Freedoom), para a musica nao depender de um lump de origem desconhecida.
#
#   src/FredGames.Bundler/Builds/build-blasphemer.sh
#
# Saida: artifacts/build/blasphemer-0.1.8/blasphemer.wad (determinístico: mesma ordem dos lumps do original).

set -euo pipefail

BL_SHA256=5838d211add81e1696a621485c1e40771035daf6609d08bad7018f52acfa5e54
FD_SHA256=3f9b264f3e3ce503b4fb7f6bdcb1f419d93c7b546f4df3e874dd878db9688f59

here="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
root="$(git -C "$here" rev-parse --show-toplevel 2>/dev/null || pwd)"
out="$root/artifacts/build/blasphemer-0.1.8"
cache="$root/artifacts/build/cache"

mkdir -p "$cache" "$out"
blzip="$cache/blasphem-0.1.8.zip"
fdzip="$cache/freedoom-0.13.0.zip"
[ -f "$blzip" ] || curl -fsSL "https://github.com/Blasphemer/blasphemer/releases/download/v0.1.8/blasphem-0.1.8.zip" -o "$blzip"
[ -f "$fdzip" ] || curl -fsSL "https://github.com/freedoom/freedoom/releases/download/v0.13.0/freedoom-0.13.0.zip" -o "$fdzip"
echo "$BL_SHA256  $blzip" | shasum -a 256 -c -
echo "$FD_SHA256  $fdzip" | shasum -a 256 -c -

python3 -I - "$blzip" "$fdzip" "$out/blasphemer.wad" <<'PY'
import re, struct, sys, zipfile

blzip, fdzip, dest = sys.argv[1:]

def read_wad(data):
    kind, count, offset = struct.unpack('<4sii', data[:12])
    assert kind == b'IWAD', kind
    lumps = []
    for i in range(count):
        pos, size, name = struct.unpack('<ii8s', data[offset + 16 * i:offset + 16 * i + 16])
        lumps.append((name.rstrip(b'\0').decode('ascii'), data[pos:pos + size]))
    return lumps

bl = read_wad(zipfile.ZipFile(blzip).read('blasphem.wad'))
fd = dict(read_wad(zipfile.ZipFile(fdzip).read('freedoom-0.13.0/freedoom1.wad')))

MAP_LUMPS = {'THINGS', 'LINEDEFS', 'SIDEDEFS', 'VERTEXES', 'SEGS', 'SSECTORS', 'NODES', 'SECTORS', 'REJECT', 'BLOCKMAP'}
out = []
i = 0
dropped = []
while i < len(bl):
    name, data = bl[i]
    m = re.fullmatch(r'E([4-9])M\d', name)
    if m:
        # marcador de fase seguido dos lumps dela
        j = i + 1
        while j < len(bl) and bl[j][0] in MAP_LUMPS:
            j += 1
        dropped.append(name)
        i = j
        continue
    if name == 'EXTENDED':
        i += 1
        continue
    if name == 'GENMIDI':
        data = fd['GENMIDI']
    out.append((name, data))
    i += 1
print('fases removidas:', ' '.join(dropped))

body = b''
directory = b''
pos = 12
for name, data in out:
    directory += struct.pack('<ii8s', pos, len(data), name.encode('ascii'))
    body += data
    pos += len(data)
wad = struct.pack('<4sii', b'IWAD', len(out), pos) + body + directory
open(dest, 'wb').write(wad)
print(len(out), 'lumps,', len(wad), 'bytes')
PY
shasum -a 256 "$out/blasphemer.wad"