# -*- coding: UTF-8 -*-

"""Base100 Codec - base100 content encoding.

Note: only works in Python3 ; strongly inspired from https://github.com/MasterGroosha/pybase100

This codec:

- en/decodes strings from str to str

- en/decodes strings from bytes to bytes

- decodes file content to str (read)

- encodes file content from str to bytes (write)

"""

from ._base import main

from ..__common__ import *

# no __examples__ ; handled manually in tests/test_base.py

class Base100DecodeError(ValueError):

__module__ = "builtins"

def base100_encode(input, errors="strict"):

input = b(input)

r = [240, 159, 0, 0] * len(input)

for i, c in enumerate(input):

r[4*i+2] = (c + 55) // 64 + 143

r[4*i+3] = (c + 55) % 64 + 128

return bytes(r), len(input)

def base100_decode(input, errors="strict"):

input = b(_stripl(input, True, True))

if errors == "ignore":

input = input.replace(b"\n", b"")

if len(input) % 4 != 0:

raise Base100DecodeError("Bad input (length should be multiple of 4)")

r = [None] * (len(input) // 4)

for i, c in enumerate(input):

if i % 4 == 2:

tmp = ((c - 143) * 64) % 256

elif i % 4 == 3:

r[i//4] = (c - 128 + tmp - 55) & 0xff

return bytes(r), len(input)

add("base100", base100_encode, base100_decode, r"^(?:base[-_]?100|emoji)$", expansion_factor=1.)

main100 = main(100, "<https://github.com/AdamNiederer/base100>")