"""
Metrics Cleanup Script
Deletes PerformanceMetric records older than 30 days to manage database size.
Intended to be run as a cron job or scheduled task.
"""

import os
import sys
from datetime import datetime, timedelta

# Add backend to path for imports
sys.path.append(os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__)))))

from core.database import SessionLocal
from core.logging import logger
from core.models.performance import PerformanceMetric


def cleanup_metrics(retention_days: int = 30):
    """Delete metrics older than retention period"""
    cutoff_date = datetime.utcnow() - timedelta(days=retention_days)
    logger.info(f"Starting metrics cleanup. Deleting records older than {cutoff_date.isoformat()}")

    db = SessionLocal()
    try:
        deleted_count = db.query(PerformanceMetric).filter(
            PerformanceMetric.timestamp < cutoff_date
        ).delete(synchronize_session=False)

        db.commit()
        logger.info(f"✅ Cleanup complete: Deleted {deleted_count} stale metric records.")
    except Exception as e:
        db.rollback()
        logger.error(f"❌ Cleanup failed: {e}")
    finally:
        db.close()

if __name__ == "__main__":
    retention = int(os.getenv("METRICS_RETENTION_DAYS", 30))
    cleanup_metrics(retention)