mirror of
https://github.com/hastagAB/Awesome-Python-Scripts.git
synced 2024-11-27 22:11:07 +00:00
76 lines
2.7 KiB
Python
76 lines
2.7 KiB
Python
|
from __future__ import print_function
|
||
|
|
import os
|
||
|
|
import string
|
||
|
|
import argparse
|
||
|
|
|
||
|
|
try:
|
||
|
|
maketrans = string.maketrans # python2
|
||
|
|
except AttributeError:
|
||
|
|
maketrans = str.maketrans # python3
|
||
|
|
|
||
|
|
|
||
|
|
def caeser_cipher(string_: str, offset: int, decode: bool, file_: string) -> None:
|
||
|
|
""" Caeser Cipher implementation, reads file or string. Also decodes.
|
||
|
|
|
||
|
|
Default implementation is ROT13 encoding.
|
||
|
|
|
||
|
|
To decode, specify the same offset you used to encode and your ciphertext / file.
|
||
|
|
|
||
|
|
:param string_: string to encode / decode
|
||
|
|
:param offset: # of chars to rotate by
|
||
|
|
:param decode: decode instead of encode
|
||
|
|
:param file_: file to read in then encode/decode
|
||
|
|
"""
|
||
|
|
if file_ and os.path.exists(file_):
|
||
|
|
with open(file_, 'r') as f:
|
||
|
|
string_ = f.read()
|
||
|
|
|
||
|
|
if decode:
|
||
|
|
offset *= -1
|
||
|
|
|
||
|
|
lower_offset_alphabet = string.ascii_lowercase[offset:] + string.ascii_lowercase[:offset]
|
||
|
|
lower_translation_table = maketrans(string.ascii_lowercase, lower_offset_alphabet)
|
||
|
|
|
||
|
|
upper_offset_alphabet = string.ascii_uppercase[offset:] + string.ascii_uppercase[:offset]
|
||
|
|
upper_translation_table = maketrans(string.ascii_uppercase, upper_offset_alphabet)
|
||
|
|
|
||
|
|
lower_converted = string_.translate(lower_translation_table)
|
||
|
|
final_converted = lower_converted.translate(upper_translation_table)
|
||
|
|
|
||
|
|
if file_:
|
||
|
|
extension = 'dec' if decode else 'enc'
|
||
|
|
with open("{}.{}".format(file_, extension), 'w') as f:
|
||
|
|
print(final_converted, file=f)
|
||
|
|
else:
|
||
|
|
print(final_converted)
|
||
|
|
|
||
|
|
|
||
|
|
def check_offset_range(value: int) -> int:
|
||
|
|
""" Validates that value is in the allowable range.
|
||
|
|
|
||
|
|
:param value: integer to validate
|
||
|
|
:return: valid integer
|
||
|
|
:raises: argparse.ArgumentTypeError
|
||
|
|
"""
|
||
|
|
value = int(value)
|
||
|
|
if value < -25 or value > 25:
|
||
|
|
raise argparse.ArgumentTypeError("{} is an invalid offset".format(value))
|
||
|
|
return value
|
||
|
|
|
||
|
|
|
||
|
|
if __name__ == '__main__':
|
||
|
|
parser = argparse.ArgumentParser(description="Simple Caeser Cipher [En,De]coder")
|
||
|
|
|
||
|
|
parser.add_argument('-d', '--decode', action='store_true', dest='decode',
|
||
|
|
help='decode ciphertext (offset should equal what was used to encode)', default=False)
|
||
|
|
parser.add_argument('-o', '--offset', dest='offset', default=13, type=check_offset_range,
|
||
|
|
help='number of characters to shift')
|
||
|
|
|
||
|
|
group = parser.add_mutually_exclusive_group(required=True)
|
||
|
|
group.add_argument('-f', '--file', dest='file', help='file to encode', default=None)
|
||
|
|
group.add_argument('-s', '--string', dest='string', help='string to encode', default=None)
|
||
|
|
|
||
|
|
args = parser.parse_args()
|
||
|
|
|
||
|
|
caeser_cipher(args.string, args.offset, args.decode, args.file)
|