caesar.py

MAX_KEY_SIZE = 26


def getMode():
    while True:
        print('Do you wish to encrypt or decrypt a message?: ')


        mode = input().lower()


        if mode in 'encrypt e decrypt d'.split():
            return mode
        else:
            print('Enter either "Encrypt" or "E" or "Decrypt" or "D" ')

def getMessage():
    print('Enter your message: ')
    return input()

def getKey():
     key = 0
     while True:
         print('Enter the key number (1-%s)' % (MAX_KEY_SIZE))
         key = int(input())
         if (key >= 1 and key <= MAX_KEY_SIZE):
             return key

def getTranslatedMessage(mode, message, key):

    translated = []

    if mode[0] == 'd':
         key = -key

    for symbol in message:
        print(symbol)
        num = 0

        # is it a letter
        if symbol.isalpha():

            # is it upper case
            if symbol.isupper():
                num = ord(symbol)
                print(num)
                # for wrapping around the alphabet
                if num > ord ('Z'):
                    num -= 26
                    print('Z ', num)
                elif num < ord('A'):
                    num += 26
                    print('A ', num)

                num = ord(symbol)
                num += key
                translated.append(num)


            # is it lower case
            elif symbol.islower():
                if num > ord('z'):
                    num -= 26
                    print('z ', num)
                elif num < ord('a'):
                    print('num' , num)
                    print('ord ', ord('a'))
                    num += 26
                    print(symbol)
                    print('a ', num)

                num = ord(symbol)
                num += key
                translated.append(num)


        # else add to the translated list
        else:
            translated.append(symbol)


            # add translated letter to list for lower

    # after we have gone through the word, we return the translate
    return translated


print("getMode()")
mode = getMode()
print("getMode: ", mode)
print("getMessage()")
message = getMessage()
print("getMessage: ", message)
print("getKey()")
key = getKey()
print("key: ", key)
print('Your translated text is: ')
result = getTranslatedMessage(mode,message,key)
print(result)