""" Joey Turner 10/7/2017
    Programming Project
"""

def get_inputs():
    """ This function will get the user to enter in all the inputs
        needed to run the program, and then return those values to the main
        program.
    """

    firstname = input("Please enter your first name > ")
        # Asks user to enter their first name
    surname = input("Please enter your surname > ")
        # Asks user to enter their surname
    gender = input("Please enter your gender, M or F > ")
        # Asks user to enter their gender
    return firstname, surname, gender
        # Returns the variables 'firstname', 'surname' and 'gender' to the
        # main program.



def validate_gender(gender):
    """ This function will validate whether the user has entered just ‘M’ or
        ‘F’ for the gender.
    """

    while gender != "M" and gender != "F":
        # Iterates this section of the function until gender is equal to
        # either 'M' or 'F'
        print("Invalid selection of gender.")
            # Notifies the user of their mistake
        gender = input("Please re-enter your gender, M or F > ")
            # Asks the user to re-enter their gender
    return gender
        # Returns the variable 'gender' to the main program.



def get_user(firstname,surname,gender):
    """ This function will create the username for the user.

        If gender==M, then username is last 3 letters of surname + first 2
            letters of first name
        If gender == F, then username is first 3 letters of first name +
            first 2 letters of surname
    """

    if gender == "F":
        # Checks whether gender = F
        username = firstname[0:3] + surname[0:2]
        # Username is assigned as the first 3 letters of the firstname, and
        # the first 2 letters of the surname
    else:
        # If username is not equal to F (should only be M after the
        # validate_gender function), username is assigned as the last 3
        # letters of the surname and the first 2 letters of the firstname.
        username = surname[-3:] + firstname[0:2]
    return username



def file_append(username):
    """ This subprogram will append the username and password to the text file
        ‘logins.txt’
    """

    myFile = open('logins.txt','a')
        # The file is opened in append mode, meaning anything written in this
        # procedure will not overwrite current data stored on the file.
    password = "Password123\n"
        # the variable password is set to 'Password123' so that it can be added
        # to the record.
    record = "Username: " + username + " " + "Password: " + password
        # Combines username and password (along with a spacer) into one variable
        # so it can be appended to the file more easily
    myFile.write(record)
        # The variable 'record' is appended to the file
    myFile.close
        # File is closed so that other programs or the user can now open it.



def main():
    """ Displays welcome and goodbye messages, calls all other subprograms.
    """

    print("=-=-= WELCOME TO THE USERNAME ASSIGNER! =-=-=")
        # Welcomes the user to the program
    firstname, surname, gender = get_inputs()
        # Calls the get_inputs function, defining the 3 variables above as
        # whatever the subprogram will return.
    validate_gender(gender)
        # Calls the validate_gender function, passing in the variable 'gender'
        # from the get_inputs function
    username = get_user(firstname,surname,gender)
        # Calls the get_user function, passing in 3 variables and defining the
        # variable 'username' as whatever the program returns
    file_append(username)
        # Calls the file_append procedure, passing in the variable 'username'
    print("Username generated at 'logins.txt': {0}".format(username))
        # Displays message to show user that the username has been successfully
        # generated, and then displays the username.

main()