"""Sweep periódico dos CSVs efêmeros gerados pelo RunSqlTool em data_storage/."""
from __future__ import annotations

import asyncio
import os
import time
from pathlib import Path
from typing import Optional

CSV_DIR = Path(__file__).parent / "data_storage"
TTL_SECONDS = int(os.environ.get("CSV_TTL_SECONDS", "1800"))
SWEEP_INTERVAL_SECONDS = int(os.environ.get("CSV_SWEEP_INTERVAL_SECONDS", "600"))

_task: Optional[asyncio.Task] = None


def sweep_once() -> int:
    """Apaga CSVs com mtime > TTL_SECONDS. Idempotente."""
    if not CSV_DIR.exists():
        return 0
    cutoff = time.time() - TTL_SECONDS
    removed = 0
    for csv in CSV_DIR.rglob("query_results_*.csv"):
        try:
            if csv.stat().st_mtime < cutoff:
                csv.unlink()
                removed += 1
        except FileNotFoundError:
            pass
    return removed


async def _periodic() -> None:
    while True:
        await asyncio.sleep(SWEEP_INTERVAL_SECONDS)
        try:
            n = sweep_once()
            if n:
                print(f"[csv_cleanup] periodic sweep removed {n} CSVs")
        except Exception as e:
            print(f"[csv_cleanup] sweep failed: {e!r}")


async def startup() -> None:
    global _task
    n = sweep_once()
    if n:
        print(f"[csv_cleanup] startup sweep removed {n} CSVs")
    _task = asyncio.create_task(_periodic())


async def shutdown() -> None:
    global _task
    if _task is not None:
        _task.cancel()
        try:
            await _task
        except asyncio.CancelledError:
            pass
        _task = None