08it-rcl.py

#!/usr/bin/env python3
import argparse
from pathlib import Path
from struct import pack, unpack, iter_unpack

__title__ = "Xanavi RCL (Un)packer"
__version__ = "0.1"
__author__ = "Gareth Bryan"
__license__ = "MIT"


def main(args):
    if args.action == 'p':
        rcl_pack(args.indir, args.outfile)
    elif args.action == 'u':
        rcl_unpack(args.infile, args.outdir)


def rcl_pack(indir, outfile):
    table_len = sum(16 for _ in indir.glob('*.png'))
    header = bytearray(0x118)
    table = bytearray()
    data = bytearray()
    header[0x00:0x20] = b'Xanavi Informatics Corporation'.ljust(0x20, b'\x00')
    header[0x20:0x50] = b'20080722-125925 08IT_OPENING_M3H'.ljust(0x30, b'\x00')
    header[0x50:0x70] = b'M3H'.ljust(0x20, b'\x00')
    header[0x70:0x74] = b'\xFF\xFF\x00\x01' # Type?
    header[0x74:0x78] = b'\xFF\xFF\xFF\xFF'
    header[0x7C:0x80] = b'\xFF\xFF\xFF\xFF'
    header[0x100:0x104] = pack('>I', 0x108)
    header[0x104:0x108] = pack('>I', 0x10C)
    header[0x108:0x10C] = pack('>I', 12)
    header[0x10C:0x110] = pack('>I', 8)
    header[0x110:0x114] = pack('>I', 0x114)
    # Write file data start
    header[0x114:0x118] = pack('>I', table_len + 4)
    # Loop through PNGs
    for p in sorted(indir.glob('*.png')):
        offset = len(header) + table_len + len(data)
        # Add file table entry
        table.extend(
            pack(
                ">4I",
                offset, offset, p.stat().st_size, p.stat().st_size
            )
        )
        with p.open('rb') as f:
            # Add png to data bytearray
            data.extend(f.read())
    # Align file to 4 bytes
    if len(data) % 4:
        padding = b'\x00' * (4 - (len(data) % 4))
        data.extend(padding)
    # Set filesize in header
    header[0x78:0x7C] = pack('>I', len(header)+len(table)+len(data))
    # Write output
    outfile.write(header)
    outfile.write(table)
    outfile.write(data)


def rcl_unpack(infile, outdir):
    infile = infile.read()
    outdir.mkdir()
    table_start, table_len = unpack('>2I', infile[0x110:0x118])
    for i, entry in enumerate(iter_unpack('>I4xI4x', infile[table_start+4:table_start+table_len])):
        offset, size = entry
        png = f'{outdir}/{i:03d}.png'
        #print(png, entry)
        with open(png, 'wb') as f:
            f.write(infile[offset:offset+size])


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description="{} v{}".format(__title__, __version__)
    )
    subparsers = parser.add_subparsers(title="Actions", dest="action", required=True)
    act_pack = subparsers.add_parser("p", help="Pack")
    act_pack.add_argument(
        "indir",
        help="Input dir",
        type=Path,
        nargs="?",
    )
    act_pack.add_argument(
        "outfile",
        help="Output RCL file",
        type=argparse.FileType("wb"),
        nargs="?",
    )
    act_unpack = subparsers.add_parser("u", help="Unpack")
    act_unpack.add_argument(
        "infile",
        help="Input RCL file",
        type=argparse.FileType("rb"),
        nargs="?",
    )
    act_unpack.add_argument(
        "outdir",
        help="Output dir",
        type=Path,
        nargs="?",
    )
    args = parser.parse_args()
    main(args)