#!/usr/bin/env python3
"""Push a local script into the running maintenance guest and run it.

    sudo owuivm-guest-run vm/images/ubuntu/by-hand.sh

WHY THIS EXISTS

Preparing a base image by hand means typing into a VNC console, and the
list of things to do to it is a hundred lines long. Everything on that
list is ordinary shell, so the only real problem is getting the text in
there - and the machine already has a channel for exactly that, the same
one every session uses.

It needs qemu-guest-agent inside the guest, which is also the one thing
on that list that genuinely has to be typed by hand: it is what this
speaks to. So the sequence is always "install the guest agent by hand,
then push the rest".

Deliberately the maintenance socket only. A session's guest belongs to
the agent, and a way to inject a script into it from the host is not
something this host should own.
"""
from __future__ import annotations

import sys

sys.path.insert(0, "/usr/local/lib/owuivm")

from guest import Guest, GuestError  # noqa: E402

SOCKET = "/run/owuivm/00000000000000000000000000000000/ga.sock"


def main(argv: list[str]) -> int:
    if len(argv) != 2:
        print(f"usage: {argv[0]} <script>", file=sys.stderr)
        return 64
    with open(argv[1], "rb") as handle:
        body = handle.read()
    remote = "/root/" + argv[1].rsplit("/", 1)[-1]

    try:
        with Guest(SOCKET, timeout=30.0) as agent:
            if not agent.ping(timeout=10.0):
                raise GuestError("the guest agent did not answer")
            agent.write_file(remote, body)
            print(f"pushed {len(body)} bytes to {remote}; running it\n", flush=True)
            # No timeout worth arguing about: this installs packages over
            # a link that is as fast as the host's, and a run that is
            # still going is not a run that has failed.
            result = agent.shell(f"bash {remote}", timeout_s=1800.0)
    except (GuestError, OSError) as exc:
        print(f"could not reach the machine: {exc}", file=sys.stderr)
        print("\nIs it running, and is qemu-guest-agent installed inside it?"
              "\n  sudo apt install -y qemu-guest-agent"
              "\n  sudo systemctl enable --now qemu-guest-agent", file=sys.stderr)
        return 69

    sys.stdout.write(result["stdout"])
    if result["stderr"].strip():
        sys.stderr.write("\n-- stderr --\n" + result["stderr"])
    print(f"\nexit code: {result['exit_code']}  ({result['seconds']}s)")
    return 0 if result["exit_code"] == 0 else 1


if __name__ == "__main__":
    raise SystemExit(main(sys.argv))