"""
CSCI146 Programming Assignment 3

Name: <Your name>
Section: <Your section>

Creativity:
<Provide a brief listing of your creativity additions so the graders know what to look for.>
"""

from random import randint, seed

ALPHABET = "abcdefghijklmnopqrstuvwxyz "

#---------------------------------------------------------
# Fools functions

# TODO: Write your fools function(s) here


#---------------------------------------------------------
# Caesar's method

def shift_letter(letter, num):
    """
    Shifts a letter up num places in the alphabet with
    wraparound.

    Args:
        letter: A single character
        num: Integer distance to shift letter

    Returns:
        Character in ALPHABET num distance from letter
    """
    # Get the index of the current letter
    index = ALPHABET.find(letter)
    # We use the mod operator (%) for wraparound
    return ALPHABET[(index + num) % len(ALPHABET)]


# TODO: Write your caesar_encrypt function here


#---------------------------------------------------------
# Substitution cipher

def splice(message, letter):
    """
    Splices out letter from message and returns the 
    remaining message. letter can only occur ONCE in
    the message
    
    For example:
    >>> splice("abcdefg", "f")
    'abcdeg'

    Args:
        message: String
        letter: A string to be removed from message

    Returns:
        String message with letter removed.
    """
    # TODO: fill in the details of this function


def keygen(password):
    """
    Given a string password, generates a new random key.
    A key consists of a random ordering of the letters in
    ALPHABET.

    Args:
        password: String password used to generate key

    Return:
        Key string
    """
    remaining = ALPHABET
    key = ""
    
    seed(password)
    
    for dummy in range(len(ALPHABET)):
        index = randint(0, len(remaining)-1)
        next_letter = remaining[index]
        key = key + next_letter
        remaining = splice(remaining, next_letter)
    
    return key
    
# TODO: Fill in your substitution functions here