import logging
import shutil
from datetime import UTC, datetime, timedelta
from pathlib import Path
from typing import Any

from src.config import get_settings

logger = logging.getLogger(__name__)


def cleanup_old_efs_directories(path: Path, retention_days: int) -> None:
    today_midnight = datetime.now(UTC).replace(
        hour=0, minute=0, second=0, microsecond=0
    )
    cutoff_timestamp = int(
        (today_midnight - timedelta(days=retention_days)).timestamp()
    )

    errors: list[str] = []

    for item in path.iterdir():
        if not item.is_dir():
            continue

        # Directory names are Unix timestamps
        if not item.name.isdecimal():
            logger.error("Non-numeric EFS directory name: %s", item.name)
            errors.append(f"Non-numeric EFS directory name: {item.name}")
            continue

        dir_timestamp = int(item.name)
        if dir_timestamp < cutoff_timestamp:
            try:
                shutil.rmtree(item)
                logger.info("Deleted EFS directory %s", item.name)
            except Exception:
                logger.exception(
                    "Failed to delete EFS directory %s",
                    item.name,
                )
                errors.append(f"Failed to delete EFS directory: {item.name}")

    if errors:
        raise RuntimeError(
            f"EFS cleanup encountered {len(errors)} error(s): " + "; ".join(errors)
        )


def handler(event: dict[str, Any] | None, context: Any) -> None:
    try:
        settings = get_settings()
        logging.getLogger().setLevel(settings.LOG_LEVEL)
        cleanup_old_efs_directories(settings.EFS_PATH, settings.EFS_RETENTION_DAYS)
    except Exception:
        logger.exception("Handler failed")
        raise