A simple script to shuffle pk3DS text dumps with a lower chance of the game crashing (by only shuffling strings with similar lengths)

pk3ds_length_shuffle.py

# shuffles a pokemon 3ds language document based on string length with a given leeway
# needs storytext.txt and gametext.txt in the same directory

from random import randrange

# amount of characters that two string lengths can be different by to allow shuffling
leeway = 3


def is_allowed_line(line):
    return not line.startswith("Text File :") and not "~~~" in line and not "[" in line


def is_fitting_line(line, other):
    return is_allowed_line(other) and abs(len(other) - len(line)) <= leeway


def shuffle(file):
    print(f"Shuffling {file}")

    with open(file + ".txt", "r", encoding="utf-16-le") as f:
        lines = f.readlines()
    # iterate through all lines and find a swap partner
    for i in range(len(lines)):
        line = lines[i]
        if not is_allowed_line(line):
            continue

        other = find_shuffle_line(lines, line)
        if other >= 0:
            # swap
            lines[i] = lines[other]
            lines[other] = line
            print(f"Shuffled {i} and {other}")

    # write to file
    with open(file + "_out.txt", "w", encoding="utf-16-le") as f:
        f.writelines(lines)
    print(f"Finished shuffling {file}")


def find_shuffle_line(lines, line):
    # find all line indices with a similar length
    possible = list(filter(lambda i: is_fitting_line(line, lines[i]), range(len(lines))))
    if len(possible) <= 0:
        return -1
    # return a random line out of the ones with similar length
    return possible[randrange(0, len(possible))]


shuffle("storytext")
shuffle("gametext")