from os.path import isfile
from random import SystemRandom
from string import punctuation, digits, ascii_letters


random = SystemRandom()


def gen_secret():
    return ''.join(random.choices(ascii_letters+digits+punctuation, k=64))


def load_or_gen_secret(path, secret_func: callable = gen_secret):
    if isfile(path):
        with open(path) as f:
            return f.read()
    else:
        from os import chmod
        with open(path, 'w') as f:
            secret = secret_func()
            f.write(secret)
        chmod(path, 0o400)
        return secret