import click
import itertools
import random
import pyperclip


lowers = "abcdefghijklmnopqrstuvwxyz"
uppers = lowers.upper()
decimals = "0123456789"


characters = list(lowers + uppers + decimals)


@click.command()
@click.option("--length", default=16, type=int)
def get_random_password(length=16):
    """ generates a random password and copies it to the clipboard """
    choice = [random.choice(characters) for i in range(length)]
    groups = [iter(choice)] * 4
    grouped = ("".join(g) for g in itertools.zip_longest(*groups, fillvalue=""))
    password = "-".join(grouped)
    pyperclip.copy(password)
    click.echo("Copied to clipboard:", err=True)
    click.echo(password)