fix main loading from command line, exit status and some cosmetics

cli.py

@@ -12,7 +12,8 @@ def main() -> None:
     """
     parser = argparse.ArgumentParser(description='Break One-Time Pad Encryption with key reuse')
     parser.add_argument('file', type=str, help='file containing hexadecimal ciphertexts, delimited by new lines')
-    parser.add_argument('-o', type=str, dest='output_file', default='result.json', help='filename to export decryptions to')
+    parser.add_argument('-o', type=str, dest='output_file', default='result.json', help='filename to export '
+                                                                                        'decryptions to')
     args = parser.parse_args()
 
     with open(args.file, 'r') as f:
@@ -21,6 +22,10 @@ def main() -> None:
     try:
         ciphertexts = list(map(bytearray.fromhex, ciphertexts))
     except ValueError as error:
-        sys.exit("Invalid hexadecimal: {error}")
+        sys.exit(f"Invalid hexadecimal: {error}")
 
     many_time_pad_attack(ciphertexts, args.output_file)
+
+
+if __name__ == "__main__":
+    main()

manytime/analysis.py

@@ -45,9 +45,10 @@ def recover_partial_key(ciphertexts: Iterable[bytearray]) -> List[Optional[int]]
                 # Although we know it is a space we don't know which ciphertext it came from
                 main_counter.update(track_spaces(xor(main_ciphertext, secondary_ciphertext)))
 
-        # Now we have tracked all the possible spaces we have seen, anchored to the index of the main ciphertext where we saw it
-        # Therefore, if we have seen a space len(ciphertexts) - 1 times in a certain position, we know that because it was present
-        # when XORd with each ciphertext, that it must have come from the main_ciphertext. Meaning, that position is a space in the main_plaintext
+        # Now we have tracked all the possible spaces we have seen, anchored to the index of the main ciphertext
+        # where we saw it Therefore, if we have seen a space len(ciphertexts) - 1 times in a certain position,
+        # we know that because it was present when XORd with each ciphertext, that it must have come from the
+        # main_ciphertext. Meaning, that position is a space in the main_plaintext
         for index, count in main_counter.items():
             if count == len(ciphertexts) - 1:
                 key[index] = ord(' ') ^ main_ciphertext[index]

manytime/interactive.py

@@ -4,7 +4,6 @@
 
 import json
 import urwid
-from enum import Enum
 
 from manytime import keys
 
@@ -13,7 +12,8 @@
 from typing import Iterable, Optional, Tuple, NoReturn, Union, Any, List
 
 
-def partial_decrypt(key: Key, ciphertext: bytearray, unknown_character: Union[Tuple[str, str], str] = ('unknown', '_')) -> Iterable:
+def partial_decrypt(key: Key, ciphertext: bytearray,
+                    unknown_character: Union[Tuple[str, str], str] = ('unknown', '_')) -> Iterable:
     """
     Decrypt ciphertext using key
     Decrypting a letter using an unknown key element will result in unknown_character
@@ -61,7 +61,8 @@ def _edit_decryption(self, letter: str) -> None:
             # Letters which are longer, for example "shift left" are not key presses we want to deal with.
             # All special characters are handled elsewhere, this code handles letters and delete keys
             # therefore we ignore all others.
-            self.application.key[index] = None if letter in self.REMOVE_KEYS or len(letter) > 1 else ord(letter) ^ ciphertext[index]
+            self.application.key[index] = None if (letter in self.REMOVE_KEYS or
+                                                   len(letter) > 1) else ord(letter) ^ ciphertext[index]
 
         # Update all decryptions
         new_decryptions = [partial_decrypt(self.application.key, c) for c in self.application.ciphertexts]

manytime/models.py

@@ -7,7 +7,7 @@
 
 from manytime import keys
 
-from typing import Optional, List, Tuple, Union, Iterator
+from typing import Optional, List, Tuple, Union, Iterator, Any
 
 
 class Key: