CaesarCipherRotating

# Coding demonstration for WiCys on the caesar cipher

def caesarEncrypt(text, key):
    # Write a caesar cipher
    cipherText = ""
    for char in text:
        
        if char.isalpha():
        # checks if the character is a letter
            if char.isupper():
            # checks if uppercase
                offset = 65 
            else:
                offset = 97
            
            #  Shift the character by the key value and add to the ASCII value of A or B (offset)
            cipherText += chr((ord(char) - offset + key) %  26 + offset)
        else:
            cipherText += char
            
    return cipherText

def caesarDecrypt(cipherText, key):
# Write a function to decrypt the above cipher using caesar Cipher algorithm
        
    plainText = ""
    
    for char in cipherText:
        if char.isalpha():
            
            if char.isupper():
                offset = 65 
            else:
                offset = 97            
            
            plainText += chr((ord(char) - offset - key) %  26 + offset)
        else:
            plainText += char
            
    return plainText


if __name__ =="__main__":
    
    choice = int(input("\n\nWelcome to WiCy's Cipher Tool!\nPlease select an option:\n1. Ceaser Cipher Encryption\n2. Ceaser Cipher Decryption\n3. Exit\n"))
    
    if choice == 1:
        # getting text to encrypt
        text = input("Enter your message to be encrypted: ")
        
        encryptKey = int(input("Enter the shift key: "))
        
        # Calling the function
        print(caesarEncrypt(text, encryptKey))
        
    elif  choice == 2:
        # Getting the ciphered text from user
        cipherText = input("Enter the ciphered message: ")
        decryptKey = int(input("Enter the shift key: "))
        
        print(caesarDecrypt(cipherText, decryptKey))