import asyncio
import os

import pytest

from app.config import get_settings
from app.maintenance import acquire, release


@pytest.mark.skipif(os.name == "nt", reason="Production shared flock semantics are POSIX")
def test_gc_excludes_active_writers(tmp_path, monkeypatch):
    monkeypatch.setenv("DATA_DIR", str(tmp_path))
    get_settings.cache_clear()
    async def check():
        writer = acquire()
        gc = asyncio.create_task(asyncio.to_thread(acquire, True))
        try:
            with pytest.raises(asyncio.TimeoutError):
                await asyncio.wait_for(asyncio.shield(gc), .1)
        finally:
            release(writer)
        maintenance = await asyncio.wait_for(gc, 3)
        release(maintenance)
    try:
        asyncio.run(check())
    finally:
        get_settings.cache_clear()