NPC DAT Renamer script for FFXI

npc_renamer.py

#!/usr/bin/env python

# npc_renamer by zach2good, use as you please!
#
# For use on the NPC DATs listed here:
# https://www.reddit.com/r/ffximodding/comments/9ndg2d/complete_list_of_zone_dats_by_zone_id/
#
# Usage: npc_renamer.py <input file to read>
#      : If the input file is .DAT, a corresponding .json file will be made.
#      : If the input file is .json, a corresponding .new.DAT file will be made.
#
# Alternate usage: npc_renamer.py <filename1> <filename2>
#                : You can use the script this way to binary compare two files.
#
# Examples:
#
# Prints the help message:
# .\npc_renamer.py
#
# Will generate 114.json, which you can edit the strings inside:
# .\npc_renamer.py 114.DAT
#
# Will generate 114.new.DAT, which you can rename and use with XIPivot or whatever:
# .\npc_renamer.py 114.json
#
# Will binary compare two files (useful to make sure the script is working as expected
# with no edits):
# .\npc_renamer.py 114.DAT 114.new.DAT

import sys
import json
import filecmp


def to_json_file(dat_filename, json_filename):
    out_dict = {}
    with open(dat_filename, mode="rb") as file:
        index = 0
        while data := file.read(32):
            last_four_bytes = list(data[0x1C:])

            data = data.split(b"\x00")[0]
            data = data.decode(encoding="ascii", errors="ignore")

            out_dict[index] = (data, last_four_bytes)

            index = index + 1

    json_data = json.dumps(out_dict, indent=4)
    with open(json_filename, "w") as out_file:
        out_file.write(json_data)


def to_dat_file(json_filename, dat_filename):
    data = {}
    with open(json_filename) as json_file:
        data = json.load(json_file)

    with open(dat_filename, "wb") as out_file:
        for value in data.values():
            name = value[0]

            if len(name) > 27:
                print(f"Name is too long!: {name}")
                print(f"Maximum length is 27, got {len(name)}.")
                sys.exit(-1)

            last_four_bytes = value[1]

            data = bytearray(32)

            data[0 : len(name)] = bytearray(name, encoding="ascii")

            data[0x1C] = last_four_bytes[0]
            data[0x1D] = last_four_bytes[1]
            data[0x1E] = last_four_bytes[2]
            data[0x1F] = last_four_bytes[3]

            out_file.write(data)


def compare(file1, file2):
    print(file1)
    print(file2)
    if filecmp.cmp(file1, file2):
        print("Files are binary twins!")
    else:
        print("Files are different!")


def print_help():
    print("Usage: npc_renamer.py <input file to read>")
    print("     : If the input file is .DAT, a corresponding .json file will be made.")
    print("     : If the input file is .json, a corresponding .new.DAT file will be made.")
    print("")
    print("Alternate usage: npc_renamer.py <filename1> <filename2>")
    print("               : You can use the script this way to binary compare two files.")


def main() -> int:
    if len(sys.argv) == 1:
        print_help()
        return -1

    if len(sys.argv) == 2:
        input_filename = sys.argv[1]
        if input_filename.endswith(".DAT"):
            output_filename = input_filename.replace(".DAT", ".json")
            to_json_file(input_filename, output_filename)
        elif input_filename.endswith(".json"):
            output_filename = input_filename.replace(".json", ".new.DAT")
            to_dat_file(input_filename, output_filename)
    elif len(sys.argv) == 3:
        filename1 = sys.argv[1]
        filename2 = sys.argv[2]
        compare(filename1, filename2)

    return 0


if __name__ == "__main__":
    sys.exit(main())