Metroid Samus Returns pkg files

parse_pkg.py

# -------------------------------------
# data is aligned to nearest 0x80
# header size is normally 0x7C aka
# 0x80 aligned, minus 4
# (doesn't include 4 bytes for the header size)
# then data size starting at [header_size + 4]
# then number of files, read 12 bytes each and seek
# 12 = hash(?), start pos, end pos (from start of file)
# then just seek to [header_size + 4] and extract files
from struct import pack, unpack
from os.path import exists
from os import mkdir
import sys
#sys.argv.append("metroidqueendeathpowerbomb.pkg")

with open(sys.argv[1], "rb") as f:
    base = ".".join(sys.argv[1].split(".")[:-1])
    header_size = unpack("<I", f.read(4))[0]
    data_size = unpack("<I", f.read(4))[0]
    file_count = unpack("<I", f.read(4))[0]
    info = []
    for i in range(file_count):
        data = unpack("<3I", f.read(12))
        info.append(data)
        print("%08X %08X %08X" % data)
    if not exists(base):
        mkdir(base)
    for i in info:
        f.seek(i[1])
        #time to do some guessing
        magic = f.read(4)
        f.seek(i[1])
        if magic == b"CWAV":
            with open(base + "/%08X.bcwav" % i[1], "wb") as o:
                o.write(f.read(i[2] - i[1]))
        elif magic == b"MANM":
            with open(base + "/%08X.anim" % i[1], "wb") as o:
                o.write(f.read(i[2] - i[1]))
        elif magic == b"MCAN":
            with open(base + "/%08X.camera" % i[1], "wb") as o:
                o.write(f.read(i[2] - i[1]))
        elif magic == b"MMDL":
            with open(base + "/%08X.model" % i[1], "wb") as o:
                o.write(f.read(i[2] - i[1]))
        elif magic == b"MTXT":
            with open(base + "/%08X.texture" % i[1], "wb") as o:
                o.write(f.read(i[2] - i[1]))
        else:
            with open(base + "/%08X.bin" % i[1], "wb") as o:
                o.write(f.read(i[2] - i[1]))