from tkinter import *
from tkinter import ttk

root = tkinter.Tk()
root.geometry("800x600")
root.wm_title("Registration Form")


users = {"root": {
        "password": "dean",
        "group": "admin"}}


def validate(form):
    if len(form) > 0:
        return False
    return True


def authorize(username, password):
    if username in users:
        if password == users[username]["password"]:
            print("Login Successful!")
            return True
    return False


def signin():
    while True:
        username = input("Username: ")
        if not len(username) > 0:
            print("Username can't be blank")
        else:
            break
    while True:
        password = input("Password: ")
        if not len(password) > 0:
            print("Password can't be blank")
        else:
            break

    if authorize(username, password):
        print("Welcome to the System.")
    else:
        print("Invalid username or password")


def signup():
    while True:
        username = input("New username: ")
        if not len(username) > 0:
            print("Username can't be blank")
            continue
        else:
            break
    while True:
        password = input("New password: ")
        if not len(password) > 0:
            print("Password can't be blank")
            continue
        else:
            break
    users[username] = {}
    users[username]["password"] = password
    users[username]["group"] = "user"
    print("Account has been created")


while True:
    option = input("> ")
    if option == "login":
        signin()
    elif option == "register":
        signup()
    elif option == "exit":
        break
    else:
        print(option + " is not an option")