Wizardry 8 save character export

"""
LICENCE: free, do whatever you want
This script exports characters from Wizardry 8 save games into CHR files.

OFFSETS:
NAME, NICKNAME  9, 29
For future use
STRENGTH        233, 237
INTELLIGENCE    253, 257
PIETY           273, 277
VITALITY        293, 297
DEXTERITY       313, 317
SPEED           333, 337
SENSES          353, 357

"""

from pathlib import Path
from argparse import ArgumentParser

# Constants: starting byte sequence of character and character data length
HEADER = b'b\x18\x00\x00\x01\x00\x00\x00'
CHRLEN = 6246


def find_all(a_str, sub):
    """
    Function to find all occurrence of substring in string
    :param a_str: string to search in
    :param sub: substring to search for
    :return: found offsets
    """
    start = 0
    while True:
        start = a_str.find(sub, start)
        if start == -1:
            return
        yield start
        start += len(sub)


def main(args):
    savebin = Path(args.save).read_bytes()
    party_offsets = list(find_all(savebin, HEADER))
    if len(party_offsets) == 0:
        print('No characters found!')
    for offset in party_offsets:
        chrbin = savebin[offset:offset+CHRLEN]
        name = ''
        index = 29
        nextchar = chrbin[index:index+1].hex()
        # print(chrbin[:28].hex(' '))
        while str(nextchar) != '00':
            name += chr(int(nextchar, 16))
            index += 2
            nextchar = chrbin[index:index+1].hex()
        print(f'Character: {name}')
        ascii = chrbin.hex(' ').split()
        ascii[8] = '00'  # clear flag "character is in party"
        export_bin = bytearray.fromhex("".join(ascii))
        Path(f'{args.folder}/{name}_{args.suffix}.CHR').write_bytes(export_bin)
        print(f'Exported file: {args.folder}/{name}_{args.suffix}.CHR')


if __name__ == '__main__':
    parser = ArgumentParser()
    parser.add_argument('--save', required=True, help="Path to Wizardry 8 SAV file")
    parser.add_argument('--suffix', default='exported', help="Suffix to add to exported CHR name")
    parser.add_argument('--folder', default='./', help="Folder to save characters")
    args = parser.parse_args()
    main(args)