#!/usr/bin/env python3
"""Logging to both stderr and the shared log file.

Kept trivial and dependency-free on purpose: systemd captures stderr, while the
file gives the same `[timestamp] message` shape the legacy shell pipeline wrote,
so existing habits (`tail -f OBSIDIAN/logs/…`) keep working.
"""
from __future__ import annotations

import sys
import threading
import time

from .config import CFG

_lk = threading.Lock()


def log(msg: str, *, level: str = "INFO") -> None:
    line = f"[{time.strftime('%F %T %z')}] {level}: {msg}"
    with _lk:
        print(line, file=sys.stderr, flush=True)
        try:
            CFG.log_file.parent.mkdir(parents=True, exist_ok=True)
            with CFG.log_file.open("a", encoding="utf-8") as f:
                f.write(line + "\n")
        except Exception:
            pass  # never let logging break the pipeline