email_validator

import tkinter as tk


def validate_email():
    # Hide all error labels
    valid_label.place_forget()
    username_error.place_forget()
    symbol_at_error.place_forget()
    domain_error.place_forget()
    more_at_error.place_forget()

    email = input_email.get()

    if len(email.split('@')[0]) < MIN_SYMBOLS_USERNAME:
        username_error.place(x=150, y=50)
        return
    elif '@' not in email:
        symbol_at_error.place(x=200, y=50)
        return
    elif email.count('@') > 1:
        more_at_error.place(x=180, y=50)
        return
    elif not any(email.endswith(f".{domain}") for domain in VALID_DOMAINS):
        domain_error.place(x=100, y=50)
        return

    valid_label.place(x=210, y=50)


MIN_SYMBOLS_USERNAME = 5
VALID_DOMAINS = ('com', 'bg', 'net', 'org')


window = tk.Tk()
window.title('Email Validator')
window.geometry('500x100')

entry_label = tk.Label(text='Enter your email:', fg='#463EAC')
entry_label.pack()

input_email = tk.Entry(window, width=15)
input_email.place(x=200, y=20)

generate_button = tk.Button(window, text='Validate', height=1, command=validate_email, fg='white', bg='blue')
generate_button.place(x=300, y=18)

username_error = tk.Label(window, text='Username must be more than 4 characters.\nTry again!', fg='Red')
symbol_at_error = tk.Label(window, text='Email must contain @!', fg='Red')
more_at_error = tk.Label(window, text='Email must contain only one @!', fg='Red')
domain_error = tk.Label(window, text=f'Domain must be one of the following: '
                                     f'{", ".join("." + domain for domain in VALID_DOMAINS)}', fg='Red')

valid_label = tk.Label(window, text='Email is valid!', fg='Blue')

window.mainloop()