Trainz 22 TZarc extractor

README.md

credit to https://github.com/rileyzzz/ChumpLib/blob/main/chumplib/src/tzarcfile.cpp for the tzarc v1 file format

tzarc.py

# trainz 22 tzarc extractor by Puyodead1
# only works for v1, v2 archives need to be decompressed first and then feed into this script

import argparse
import pathlib
import struct

# pip install binreader
from binreader import BinaryReader


def swap32(i):
    return struct.unpack("<I", struct.pack(">I", i))[0]


def serialize_string(reader: BinaryReader):
    str_len = reader.read_byte()
    return reader.read_string(str_len)


class TZArcFile:
    name: str
    size: int
    data: bytes

    def __init__(self):
        pass


def extract(reader: BinaryReader, file_path: str, list_only: bool):
    file_count = swap32(reader.read_uint32())
    print(f"File Count: {file_count}")

    files = []

    for i in range(file_count):
        file = TZArcFile()

        file_name = serialize_string(reader)
        file.name = file_name
        # compression?
        unknown = swap32(reader.read_uint32())
        file_size = swap32(reader.read_uint32())
        file.size = file_size

        files.append(file)

        # print(f"[DEBUG] File {file_name} size {file_size}")

    # crc?
    unknown2 = swap32(reader.read_uint32())
    # print(f"[DEBUG] Unknown2: {unknown2}")

    for i in range(file_count):
        file = files[i]
        file_name = file.name
        file.data = reader.read(file.size)

        # print(f"[DEBUG] Read file data for {file.name}, stream pos {reader.tell()}")

    if list_only:
        for file in files:
            print(file.name)
        return

    # create a directory using the name of the file
    dir_name = pathlib.Path(file_path).stem.replace(" ", "_")

    for file in files:
        fp = pathlib.Path(dir_name, file.name)
        fp.parent.mkdir(exist_ok=True, parents=True)

        print(f"Writing {fp}")
        with open(fp, "wb") as f:
            f.write(file.data)


def main(file_path: str, list_only: bool):
    with open(file_path, "rb") as f:
        reader = BinaryReader(f)

        magic = reader.read_uint32()
        assert magic == 0x63615A54, "Not a valid TZArc file"

        version = swap32(reader.read_uint32())
        print(f"File Version: {version}")

        if version == 2:
            raise AssertionError("Version 2 archives need to be decompressed first!")

        assert version == 1, "Unsupported version"

        extract(reader, file_path, list_only)


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Auran TZArc extractor")
    parser.add_argument("file", help="The file to extract")
    parser.add_argument("--list", help="List files instead of extracting", action="store_true")

    args = parser.parse_args()

    main(args.file, args.list)