"""Glue service: cross-domain writes for order ↔ calendar-entry bridging.

These run in the *same* DB transaction as the caller — not event-driven —
because order creation and payment confirmation need immediate consistency.
"""
from __future__ import annotations

from sqlalchemy import select, update
from sqlalchemy.ext.asyncio import AsyncSession

from events.models.calendars import CalendarEntry, Calendar


async def claim_entries_for_order(
    session: AsyncSession,
    order_id: int,
    user_id: int | None,
    session_id: str | None,
    page_post_id: int | None = None,
) -> None:
    """Mark pending CalendarEntries as 'ordered' and set order_id."""
    filters = [
        CalendarEntry.deleted_at.is_(None),
        CalendarEntry.state == "pending",
    ]

    if user_id is not None:
        filters.append(CalendarEntry.user_id == user_id)
    elif session_id is not None:
        filters.append(CalendarEntry.session_id == session_id)

    if page_post_id is not None:
        cal_ids = select(Calendar.id).where(
            Calendar.container_type == "page",
            Calendar.container_id == page_post_id,
            Calendar.deleted_at.is_(None),
        ).scalar_subquery()
        filters.append(CalendarEntry.calendar_id.in_(cal_ids))

    await session.execute(
        update(CalendarEntry)
        .where(*filters)
        .values(state="ordered", order_id=order_id)
    )


async def confirm_entries_for_order(
    session: AsyncSession,
    order_id: int,
    user_id: int | None,
    session_id: str | None,
) -> None:
    """Mark ordered CalendarEntries as 'provisional'. Called when payment confirms."""
    filters = [
        CalendarEntry.deleted_at.is_(None),
        CalendarEntry.state == "ordered",
        CalendarEntry.order_id == order_id,
    ]

    if user_id is not None:
        filters.append(CalendarEntry.user_id == user_id)
    elif session_id is not None:
        filters.append(CalendarEntry.session_id == session_id)

    await session.execute(
        update(CalendarEntry)
        .where(*filters)
        .values(state="provisional")
    )


async def get_entries_for_order(
    session: AsyncSession,
    order_id: int,
) -> list[CalendarEntry]:
    """Return CalendarEntries for an order. Replaces Order.calendar_entries relationship."""
    result = await session.execute(
        select(CalendarEntry).where(
            CalendarEntry.order_id == order_id,
            CalendarEntry.deleted_at.is_(None),
        )
    )
    return list(result.scalars().all())