# -----------------------------------------------------------------------------
# Name:        translate
# Purpose:     assignment # 3
#
# Author:
# Date:
# -----------------------------------------------------------------------------
"""
Enter your docstring with a one-line overview here

and a more detailed description here.
"""


def starts_with_vowel(word):
    """
    Enter your function docstring here

    This function checks if word is greater than one, alphanumeric, lower case
    and a vowel

    parameter : word (string)

    """
    # return True if the word starts with a vowel and False otherwise
    # #if length of word is greater than 0 and word is alphanumeric
    if len(word) > 0 and word.isalpha():
        # Convert word to lowercase and transform into word_conversion variable
        word_conversion = word.lower()
        # The 1st letter you input as word transform into first_letter variable
        first_letter = word_conversion[0]
        # if the first letter is a vowel
        if first_letter in ('a', 'e', 'i', 'o', 'u'):
            return True
        else:
            return False
    else:
        print("empty")


def encrypt(word):
    """
    Enter your function docstring here
    parameters : word (string)
    """
    # encrypt a single word into the secret language
    # call starts_with_vowel to decide which pattern to follow
    new_word_encrypt = starts_with_vowel(word)
    if new_word_encrypt is True:
        new_word_tan = word + 'tan'
        # return a single word (encrypted)
        return new_word_tan
    else:
        new_word_est = word[1:] + word[0] + 'est'
        # return a single word (encrypted)
        return new_word_est
        # return a single word (encrypted)


def decrypt(word):
    """
    Enter your function docstring here
    parameters: word (string)
    """
    # decrypt a single word from the secret language
    if word[0] in ('a', 'e', 'i', 'o', 'u') and word[-3:] == 'tan':
        word_sans_tan = word[:-3]
        return word_sans_tan
    elif word[0] not in ('a', 'e', 'i', 'o', 'u') and word[-3] == 'est':
        word_sans_est = word[-4] + word + word[-4:]
        return word_sans_est
    else:
        # If the word is not a valid word in the secret language, return None
        print('None, invalid message')


def translate(text, mode):
    """
    Enter your function docstring here

    parameters: text (string)
                mode (string)
                word (string)
                translated message (string)
                encrypted_word (string)
                reversed_list (string)
                encrypted_list (string)
    """
    # Translate (encrypt or decrypt) the whole message
    # Split the text into a list of words
    list_words = text.split()
    # if mode is 'E' encrypt each of the words in the list
    translate_list = []
    if mode == "E":
        for word in list_words:
            encrypted_word = encrypt(word)
            # Build a new list with these translated words
            translate_list.append(encrypted_word)

    # if mode id 'D' decrypt each word in the list
    if mode == "D":
        for word in list_words:
            decrypted_word = decrypt(word)
            # Build a new list with these translated words
            translate_list.append(decrypted_word)

    translate_list.reverse()
    final_list = " ".join(translate_list)
    # and return it
    return final_list
    # final_transformation = reversed_list
    # return final_transformation


def choose_mode():
    """
    Enter your function docstring here
    """
    # Prompt the user for input repeatedly until they enter 'E' or 'D'.
    while True:
        user_input = input("Please type E to encrypt or D to" +
                           " decrypt a message:")
        # Return the user's choice.
        if user_input in ('E', 'D'):
            # Return the user's choice.
            return user_input
        else:
            print("Invalid Choice")


def main():
    # Get the user choice 'E' or 'D' and save it in a variable.
    user_choice = choose_mode()
    # Prompt the user for the message to be translated.
    if user_choice in ('E', 'D'):
        message = input("Please enter your message:")
        translated_message = translate(message, user_choice)
        print(translated_message)
    else:
        print("Invalid Choice")


if __name__ == '__main__':
    main()