"""Phase 0 worker stub: a heartbeat line every 30 s and a touched beat file; exits on SIGTERM."""

from __future__ import annotations

import logging
import os
import signal
import threading
import time
from pathlib import Path

log = logging.getLogger("packetstation.worker")

BEAT_SECONDS = 30
STALE_SECONDS = 90


def touch(path: Path) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.touch(exist_ok=True)
    now = time.time()
    os.utime(path, (now, now))


def run(beat_file: Path, build: str, stop: threading.Event | None = None, interval: float = BEAT_SECONDS) -> int:
    stop = stop or threading.Event()

    def _stop(signum: int, _frame: object) -> None:
        log.info("worker stopping on signal %s", signum)
        stop.set()

    if threading.current_thread() is threading.main_thread():
        signal.signal(signal.SIGTERM, _stop)
        signal.signal(signal.SIGINT, _stop)
    log.info("worker started", extra={"ps": {"build": build, "beat_file": str(beat_file)}})
    while not stop.is_set():
        try:
            touch(beat_file)
        except OSError as e:
            log.error("can't touch beat file %s: %s", beat_file, e.strerror)
        log.info("heartbeat", extra={"ps": {"build": build}})
        stop.wait(interval)
    log.info("worker stopped")
    return 0


def beat_age(beat_file: Path) -> float | None:
    try:
        return time.time() - beat_file.stat().st_mtime
    except OSError:
        return None