Caesar Cipher and The Vigenère Cipher - encoder or decoder

simple_two_cipher.py

# Caesar Cipher!

def decoder(message, offset):
    result=""
    for i in range(len(message)):
        if not(ord("a")<=ord(message[i])<=ord("z")):
            result+=message[i]
            continue
        elif ord(message[i])+offset>ord("z"):
            result += chr(ord(message[i])-26+offset)
            continue
        result += chr(ord(message[i])+offset)
    return(result)

def coder(message, offset):
    result=""
    for i in range(len(message)):
        if not(ord("a")<=ord(message[i])<=ord("z")):
            result+=message[i]
            continue
        elif ord(message[i])-offset<ord("a"):
            result += chr(ord(message[i])+26-offset)
            continue
        result += chr(ord(message[i])-offset)
    return(result)

def fdecoder(text):
    for i in range(26):
        print("Offset: ", i)
        print(decoder(text, i))
        print("\n")
    return "Done!"

# The Vigenère Cipher

def index(st):
    return ord(st)-ord('a')
def rindex(num):
    return chr(num+ord('a'))

def vdcode(message, key):
    long=[]
    keyl= key*len(message)
    for i in range(len(message)):
        if not("a"<= message[i] <="z"):
            long.append(" ")
            continue
        long.append(keyl[0])
        keyl= keyl[1:]

    result=""

    for i in range(len(message)):
        if not("a"<= message[i] <="z"):
            result += message[i]
            continue
        elif index(message[i])-index(long[i]) < 0:
            result += rindex(index(message[i])-index(long[i])+26)
            continue
        result += rindex(index(message[i])-index(long[i]))
    return result

def vcode(message, key):
    long=[]
    keyl= key*len(message)
    for i in range(len(message)):
        if not("a"<= message[i] <="z"):
            long.append(" ")
            continue
        long.append(keyl[0])
        keyl= keyl[1:]

    result=""

    for i in range(len(message)):
        if not("a"<= message[i] <="z"):
            result += message[i]
            continue
        elif index(message[i])+index(long[i]) >= 26:
            result += rindex(index(message[i])+index(long[i])-26)
            continue
        result += rindex(index(message[i])+index(long[i]))
    return result

def text(text, choice):
    print(f"Please Give me the {text} to {choice}")
    return input("=> ")

def encode():
    message= text("text","encode")

    print("Which encryption method do you want to use?")
    print("1) Caesar Cipher")
    print("2) Vigenère Cipher")
    option = int(input("=> "))

    if option  == 1:
        offset= int(text("offset", "encode"))
        print(coder(message, offset))
    elif option  == 2:
        key= text("key (word)", "encode")
        print(vcode(message, key))
    else:
        print("Please enter 1 or 2.")
        encode()

def decode():
    message= text("text","decode")

    print("Which encryption method do you want to use?")
    print("1) Caesar Cipher")
    print("2) Caesar Cipher (brute force - wihtout key)")
    print("3) Vigenère Cipher")
    option = int(input("=> "))

    if option  == 1:
        offset= int(text("offset", "encode"))
        print(decoder(message, offset))
    elif option == 2:
        fdecoder(message)
    elif option == 3:
        key= text("key (word)", "encode")
        print(vdcode(message, key))
    else:
        print("Please enter 1 or 2.")
        encode()

def choice():
    option=0
    print("What do you want to do?")
    print("1) encode")
    print("2) decode")
    option= int(input("=> "))
    print("Option ", option)

    if option == 1:
        encode()
    elif option == 2:
        decode()
    else:
        print("Please enter 1 or 2.")
        choice()

choice()