from __future__ import annotations

from datetime import datetime, timedelta, timezone
from pathlib import Path

from ..core.config import OUTPUT_DIR


def cleanup_outputs(retention_days: int) -> int:
    if retention_days <= 0:
        return 0
    OUTPUT_DIR.mkdir(parents=True, exist_ok=True)
    cutoff = datetime.now(timezone.utc) - timedelta(days=retention_days)
    removed = 0
    for item in OUTPUT_DIR.iterdir():
        if not item.is_dir():
            continue
        dt = _parse_date(item.name)
        if dt and dt < cutoff:
            _remove_tree(item)
            removed += 1
    return removed


def _parse_date(name: str) -> datetime | None:
    try:
        return datetime.strptime(name, "%Y-%m-%d").replace(tzinfo=timezone.utc)
    except ValueError:
        return None


def _remove_tree(path: Path) -> None:
    for child in path.glob("**/*"):
        if child.is_file():
            child.unlink(missing_ok=True)
    for child in sorted(path.glob("**/*"), reverse=True):
        if child.is_dir():
            child.rmdir()
    path.rmdir()