def __init__(self, rotors: list):
# Make an empty list of rotor objects
self.rotors = []
# Populate self.rotors with 3 rotor objects
for order, rotor in enumerate(rotors):
if rotor[0] == "I":
# The Represent Function is enables setting the rotors with letters
window_position = represent(rotor[1])
ring_setting = represent(rotor[2])
self.rotors.append(RotorI(window_position, ring_setting,
order))
elif rotor[0] == "II":
window_position = represent(rotor[1])
ring_setting = represent(rotor[2])
self.rotors.append(
RotorII(window_position, ring_setting, order))
elif rotor[0] == "III":
window_position = represent(rotor[1])
ring_setting = represent(rotor[2])
self.rotors.append(
RotorIII(window_position, ring_setting, order))
elif rotor[0] == "IV":
window_position = represent(rotor[1])
ring_setting = represent(rotor[2])
self.rotors.append(
RotorIV(window_position, ring_setting, order))
elif rotor[0] == "V":
window_position = represent(rotor[1])
ring_setting = represent(rotor[2])
self.rotors.append(RotorV(window_position, ring_setting,
order))
def __init__(self, pairs: str):
# Initiate plugboard connections
self.letter_pairs = {}
# Populate plugboard settings
pairs = pairs.split()
for letter_pair in pairs:
first_letter = represent(letter_pair[0])
second_letter = represent(letter_pair[1])
self.letter_pairs[first_letter] = second_letter
self.letter_pairs[second_letter] = first_letter
def encrypt_decrypt(self, letter: int):
# Encrypt or decrypts a letter
# Feed the letter to the plugboard:
if letter in self.plugboard.letter_pairs:
plugboard_output_1 = self.plugboard.plug(letter)
else:
plugboard_output_1 = letter # If there is no connection in plugboard, return the letter
# Feed plugboard output to Rotor Set(First pass from right to left):
rotor_output_1 = self.rotor_set.right_to_left(plugboard_output_1)
# Feed rotor output to reflector
reflector_output = self.reflector.reflect(rotor_output_1)
# Feed reflector output back to rotor:
rotor_output_2 = self.rotor_set.left_to_right(reflector_output)
# Feed rotor output to plugboard again
if rotor_output_2 in self.plugboard.letter_pairs:
plugboard_output_2 = self.plugboard.plug(rotor_output_2)
else:
plugboard_output_2 = rotor_output_2 # If there is no connection in plugboard, return the letter
# return the result as letter
return represent(
plugboard_output_2
) # Represent is added to Output the letter as an alphabetic letter
def encode_decode(enigma_machine, message):
# Encode or Decode the message
message = message.replace(" ", "") # Remove spaces in message
converted_text = [
enigma_machine.encrypt_decrypt(represent(i)) for i in message
]
# Return the Message
return "".join(converted_text)
def left_to_right(self, letter: int):
# The following code encodes a letter from right to left (First run across Rotors)
# Within a rotor, INFORMATION flow is Flat Contact -> Window (INFORMATION) -> Wiring ->
# Spring Contact ->PlugBoard/Right Rotor
# Flat Contact -> Window (INFORMATION)
window = (letter + self.window_position) % 26
# Window (INFORMATION) -> Wiring
wiring = (window - self.ring_setting) % 26
# Wiring -> Spring Contact
spring_contact = (self.wiring.index(represent(wiring))) % 26
# Spring Contact -> Plugboard
plugboard = (spring_contact - self.window_position +
self.ring_setting) % 26
# Return the letter
return plugboard
def right_to_left(self, letter: int):
# The following code encodes a letter from right to left (First run across Rotors)
# Within a rotor, INFORMATION flow is PlugBoard/Right Rotor -> Spring Contact -> Wiring ->
# Window (INFORMATION) -> Flat Contact
# Plugboard -> Spring Contact
spring_contact = (letter + self.window_position -
self.ring_setting) % 26
# Spring Contact -> Wiring
wiring = (represent(self.wiring[spring_contact])) % 26
# Wiring -> Window (INFORMATION)
window = (wiring + self.ring_setting) % 26
# Window (INFORMATION) -> Flat Contact
flat_contact = (window - self.window_position) % 26
# Return the letter
return flat_contact
def reflect(self, letter: int):
return represent(self.wiring[letter])