#!/usr/bin/python3

'''

@odin

'''

from random import randint as ri

_charset = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'

def main():

while True:

print('\n\t\t\t|| Cipher Algorithms ||')

print('''\n1. Additive Cipher\n2. Ceaser Cipher\n3. One Time Pad Cipher\n4. AutoKey Cipher\n5. Exit\n''')

ch = int(input('Enter your choice : '))

if ch is 1:

additive()

elif ch is 2:

ceaser()

elif ch is 3:

otpc()

elif ch is 4:

AutoKey()

elif ch is 5:

exit(0)

else:

print('Invalid Choice')

pass

# end of main

def additive():

_plainText = ''

_cipherText = ''

print('\n\n\t\t|| Additive Cipher ||\n')

print('''\n1. Encrypt Message\n2. Decrypt Message\n3. Return to main\n''')

ch = int(input('Enter your choice : '))

if ch is 1:

_cipherText = ''

_plainText = str(input('\nEnter message to encrypt : ')).upper().replace(" ","")

key = int(input('Enter key in range[0-25] : '))

if key>25 and key < 0:

print("Invalid key value")

additive()

for index,i in enumerate(_plainText):

char = _charset.find(i) + key

if char > 25:

char = char%26

_cipherText += _charset[char]

print("\nYour message '{}' is Encrypted as '{}'\n".format(_plainText.lower(),_cipherText))

input('press ENTER to continue\n')

additive()

elif ch is 2:

_plainText = ''

_cipherText = str(input('\nEnter message to decrypt : ')).upper().replace(" ","")

key = int(input('Enter key in range[0-25] : '))

if key>25 and key < 0:

print("Invalid key value")

additive()

for index,i in enumerate(_cipherText):

char = _charset.find(i) - key

if char < 0:

char += 26

_plainText += _charset[char]

print("\nYour message '{}' is decrypted as '{}'\n".format(_cipherText,_plainText.lower()))

input('press ENTER to continue\n')

additive()

elif ch is 3:

pass

else:

print('Invalid Choice')

additive()

def ceaser():

_plainText = ''

_cipherText = ''

key = 3

print('\n\n\t\t|| Ceaser Cipher ||\n')

print('''\n1. Encrypt Message\n2. Decrypt Message\n3. Return to main\n''')

ch = int(input('Enter your choice : '))

if ch is 1:

_cipherText = ''

_plainText = str(input('\nEnter message to encrypt : ')).upper().replace(" ","")

for index,i in enumerate(_plainText):

char = _charset.find(i) + key

if char > 25:

char = char%26

_cipherText += _charset[char]

print("\nYour message '{}' is Encrypted as '{}'\n".format(_plainText.lower(),_cipherText))

input('press ENTER to continue\n')

ceaser()

elif ch is 2:

_plainText = ''

_cipherText = str(input('\nEnter message to decrypt : ')).upper().replace(" ","")

for index,i in enumerate(_cipherText):

char = _charset.find(i) - key

if char < 0:

char += 26

_plainText += _charset[char]

print("\nYour message '{}' is decrypted as '{}'\n".format(_cipherText,_plainText.lower()))

input('press ENTER to continue\n')

ceaser()

elif ch is 3:

pass

else:

print('Invalid Choice')

ceaser()

def otpc():

_plainText = ''

_cipherText = ''

key = ''

print('\n\n\t\t|| OneTimePad Cipher ||\n')

print('''\n1. Encrypt Message\n2. Return to main\n''')

ch = int(input('Enter your choice : '))

if ch is 1:

_cipherText = ''

_plainText = str(input('\nEnter message to encrypt : ')).upper().replace(" ","")

for char in range(len(_plainText)):

key += _charset[ri(0,25)]

for index,i in enumerate(_plainText):

char = _charset.find(i) + _charset.find(key[index])

if char > 25:

char -= 26

_cipherText += _charset[char]

print("\nYour message '{}' is Encrypted as '{}' using key {}\n".format(_plainText.lower(),_cipherText,key))

input('press ENTER to continue\n')

otpc()

elif ch is 2:

pass

else:

print('Invalid Choice')

otpc()

def AutoKey():

_plainText = ''

_cipherText = ''

print('\n\n\t\t|| AutoKey Cipher ||\n')

print('''\n1. Encrypt Message\n2. Decrypt Message\n3. Return to main\n''')

ch = int(input('Enter your choice : '))

if ch is 1:

_cipherText = ''

_plainText = str(input('\nEnter message to encrypt : ')).upper().replace(" ","")

key = int(input('Enter key in range[0-25] : '))

if key>25 and key < 0:

print("Invalid key value")

AutoKey()

for index,i in enumerate(_plainText):

if index is 0:

char = _charset.find(i) + key

else:

char = _charset.find(i) + _charset.find(_plainText[index - 1])

if char > 25:

char %= 26

_cipherText += _charset[char]

print("\nYour message '{}' is Encrypted as '{}'\n".format(_plainText.lower(),_cipherText))

input('press ENTER to continue\n')

AutoKey()

# Decryption main logic by keyser soze! Hail PappA

elif ch is 2:

_plainText = ''

_cipherText = str(input('\nEnter message to decrypt : ')).upper().replace(" ","")

key = int(input('Enter key in range[0-25] : '))

if key>25 and key < 0:

print("Invalid key value")

AutoKey()

for index,i in enumerate(_cipherText):

if index is 0:

char = _charset.find(i) - key

else:

char = _charset.find(i) - _charset.find(_plainText[index - 1])

if char < 0:

char += 26

print(char)

_plainText += _charset[char]

print("\nYour message '{}' is decrypted as '{}'\n".format(_cipherText,_plainText.lower()))

input('press ENTER to continue\n')

AutoKey()

elif ch is 3:

pass

else:

print('Invalid Choice')

AutoKey()

# Avoid exection of complete module while importing into other script

if __name__ == '__main__' :

main()