"""Report the nested client status to the outer Gamescope supervisor."""

from __future__ import annotations

import argparse
import os
from pathlib import Path
import subprocess
import sys
from collections.abc import Sequence


def _process_exit_status(returncode: int) -> int:
	if returncode < 0:
		return 128 + min(-returncode, 127)
	return min(returncode, 255)


def run_and_record(command: Sequence[str], status_file: Path) -> int:
	if not command:
		raise ValueError("nested game command cannot be empty")
	try:
		process = subprocess.Popen([str(value) for value in command])
	except OSError as exc:
		print(f"Could not start the nested game command: {exc}", file=sys.stderr)
		returncode = 127
	else:
		try:
			returncode = int(process.wait())
		except BaseException:
			if process.poll() is None:
				process.terminate()
				try:
					process.wait(timeout=2.0)
				except subprocess.TimeoutExpired:
					process.kill()
					process.wait()
			raise

	temporary = status_file.with_name(f".{status_file.name}.{os.getpid()}.tmp")
	try:
		temporary.write_text(f"{returncode}\n", encoding="ascii")
		os.replace(temporary, status_file)
	except OSError as exc:
		print(f"Could not report the nested game status: {exc}", file=sys.stderr)
		try:
			temporary.unlink()
		except FileNotFoundError:
			pass
	return _process_exit_status(returncode)


def main(argv: Sequence[str] | None = None) -> int:
	parser = argparse.ArgumentParser()
	parser.add_argument("--status-file", required=True, type=Path)
	parser.add_argument("command", nargs=argparse.REMAINDER)
	arguments = parser.parse_args(argv)
	command = arguments.command
	if command and command[0] == "--":
		command = command[1:]
	try:
		return run_and_record(command, arguments.status_file)
	except ValueError as exc:
		print(f"Nested game launch failed: {exc}", file=sys.stderr)
		return 1


if __name__ == "__main__":
	raise SystemExit(main())