"""File rotation utilities for logs and metrics."""
import logging
from datetime import UTC, datetime
from pathlib import Path
logger = logging.getLogger(__name__)
def get_rotated_file(base_path: Path, rotation_days: int) -> Path:
"""Get current file with rotation, creating new timestamped file if needed."""
pattern = f"{base_path.stem}_*{base_path.suffix}"
existing = sorted(base_path.parent.glob(pattern))
if existing:
latest = existing[-1]
try:
# Extract timestamp: web-search_2025-10-13.log -> 2025-10-13
timestamp_str = latest.stem.split("_")[-1]
file_date = datetime.strptime(timestamp_str, "%Y-%m-%d")
# Check if still within rotation period
days_since = (datetime.now(UTC).replace(tzinfo=None) - file_date).days
if days_since < rotation_days:
return latest
# Rotation period passed - delete old files
for old_file in existing:
old_file.unlink()
logger.info("Deleted old file: %s", old_file.name)
except (ValueError, IndexError) as e:
logger.warning("Failed to parse timestamp from %s: %s", latest, e)
# Create new timestamped file
timestamp = datetime.now(UTC).strftime("%Y-%m-%d")
new_file = base_path.parent / f"{base_path.stem}_{timestamp}{base_path.suffix}"
logger.info("Created new rotated file: %s", new_file.name)
return new_file
