"""Alert endpoints."""
from datetime import datetime, timedelta, UTC
from flask import request
from . import bp, paginate
from ..models import Alert
from ..extensions import db


@bp.route('/alerts')
def list_alerts():
    """List alerts with filters."""
    alert_type = request.args.get('type')
    sensor_id = request.args.get('sensor_id', type=int)
    hours = request.args.get('hours', 24, type=int)

    since = datetime.now(UTC) - timedelta(hours=hours)
    query = db.select(Alert).where(Alert.timestamp >= since).order_by(Alert.timestamp.desc())

    if alert_type:
        query = query.where(Alert.alert_type == alert_type)
    if sensor_id:
        query = query.where(Alert.sensor_id == sensor_id)

    result = paginate(query, Alert.to_dict)
    return {'alerts': result['items'], 'total': result['total'],
            'limit': result['limit'], 'offset': result['offset']}