decode support

[rfc1751] / rfc1751.py

# Copyright (c) 2024 Scott Worley <scottworley@scottworley.com>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.


import sys

from rfc1751wordlist import WORD_LIST, WORD_LIST_SIZE


WORD_LIST_INVERTED = {word: i for (i, word) in enumerate(WORD_LIST)}
assert len(WORD_LIST_INVERTED) == WORD_LIST_SIZE


def encode_actual(x: int) -> list[str]:
    return [] if x <= 0 else encode_actual(
        x // WORD_LIST_SIZE) + [WORD_LIST[x % WORD_LIST_SIZE]]


def encode(x: int) -> list[str]:
    return [WORD_LIST[x]] if x == 0 else encode_actual(x)


def decode(x: list[str]) -> int:
    return WORD_LIST_SIZE * decode(x[:-1]) + \
        WORD_LIST_INVERTED[x[-1]] if x else 0


def main() -> None:
    if sys.argv[1].isnumeric():
        print(' '.join(encode(int(sys.argv[1]))))
    elif len(sys.argv) == 2:
        print(decode(sys.argv[1].split(' ')))
    else:
        print(decode(sys.argv[1:]))


if __name__ == '__main__':
    main()