"""监控查询只使用固定字段与有界窗口；事务由服务层负责。"""

from sqlalchemy import func, select

from app.models.monitor import MonitorEvent, MonitorRequestMinute, MonitorSnapshot


def snapshots(session, start, end):
    return session.scalars(
        select(MonitorSnapshot)
        .where(MonitorSnapshot.minute >= start, MonitorSnapshot.minute < end)
        .order_by(MonitorSnapshot.minute)
        .limit(10082)
    ).all()


def request_minutes(session, start, end, route=None):
    statement = select(MonitorRequestMinute).where(
        MonitorRequestMinute.minute >= start, MonitorRequestMinute.minute < end
    )
    if route:
        statement = statement.where(MonitorRequestMinute.route == route)
    return session.scalars(
        statement.order_by(MonitorRequestMinute.minute.desc()).limit(20001)
    ).all()


def events(session, query, start, end):
    filters = [MonitorEvent.last_seen >= start, MonitorEvent.first_seen < end]
    if query.kind:
        filters.append(MonitorEvent.kind == query.kind)
    if query.request_id:
        filters.append(MonitorEvent.request_id == query.request_id)
    if query.route:
        filters.append(MonitorEvent.route == query.route)
    if query.active_only:
        filters.extend([MonitorEvent.kind == "HEALTH", MonitorEvent.resolved_at.is_(None)])
    total = session.scalar(select(func.count()).select_from(MonitorEvent).where(*filters)) or 0
    rows = session.scalars(
        select(MonitorEvent)
        .where(*filters)
        .order_by(MonitorEvent.last_seen.desc(), MonitorEvent.id.desc())
        .offset(query.offset)
        .limit(query.page_size)
    ).all()
    return rows, total


def active_events(session):
    return session.scalars(
        select(MonitorEvent)
        .where(MonitorEvent.kind == "HEALTH", MonitorEvent.resolved_at.is_(None))
        .order_by(MonitorEvent.last_seen.desc())
        .limit(100)
    ).all()


def event(session, event_id):
    return session.get(MonitorEvent, event_id)