"""Alert queries shared by the alerts pages and the MCP tools.

Each function takes an open session and returns rows, with no Quart request
context, so the routes and the /mcp tools (which run outside Quart's pipeline)
call the same code.
"""
from __future__ import annotations

from sqlalchemy import select

from steward.models.alerts import AlertRule, AlertState, AlertStateEnum, MaintenanceWindow

# States that need someone's attention: pending (breaching, not yet for long
# enough), firing, and acknowledged-but-still-breaching.
ACTIVE_STATES = (AlertStateEnum.firing, AlertStateEnum.acknowledged, AlertStateEnum.pending)


async def active_alerts(db) -> list:
    """(AlertState, AlertRule) rows not yet resolved, latest transition first."""
    return list((await db.execute(
        select(AlertState, AlertRule)
        .join(AlertRule, AlertState.rule_id == AlertRule.id)
        .where(AlertState.state.in_(ACTIVE_STATES))
        .order_by(AlertState.last_transition_at.desc())
    )).all())


async def list_rules(db) -> list[AlertRule]:
    return list((await db.execute(select(AlertRule).order_by(AlertRule.name))).scalars())


async def list_maintenance_windows(db) -> list[MaintenanceWindow]:
    """Every window, latest start first."""
    return list((await db.execute(
        select(MaintenanceWindow).order_by(MaintenanceWindow.start_at.desc())
    )).scalars())