#!/usr/bin/env python3
"""Write two disposable 32-byte custody keys into an empty private directory."""
import argparse
import os
from pathlib import Path


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("directory", type=Path)
    root = parser.parse_args().directory
    if any(root.iterdir()):
        raise SystemExit(f"{root} is not empty")
    for name in ("master-key", "signing-key"):
        path = root / name
        path.write_bytes(os.urandom(32))
        path.chmod(0o600)


if __name__ == "__main__":
    main()