"""GET /api/sms — SMS log list.

Read-only query over the mirrored ``sms`` table. Filters: ``user_id`` and a
ms-epoch ``[start, end]`` window compared against ``create_time`` (inclusive).
Ordered by ``create_time desc`` (nulls last) — newest first.
"""

from __future__ import annotations

from typing import Annotated

import sqlalchemy as sa
from fastapi import APIRouter, Depends, Query
from sqlalchemy.ext.asyncio import AsyncSession

from app.api.deps import get_session
from app.api.schemas import Page, SmsOut
from app.db.models import Sms

router = APIRouter(prefix="/api", tags=["sms"])

SessionDep = Annotated[AsyncSession, Depends(get_session)]
PageParam = Annotated[int, Query(ge=1)]
PageSizeParam = Annotated[int, Query(ge=1, le=100)]


@router.get("/sms")
async def list_sms(
    session: SessionDep,
    page: PageParam = 1,
    page_size: PageSizeParam = 20,
    user_id: Annotated[str | None, Query()] = None,
    start: Annotated[int | None, Query(ge=0)] = None,
    end: Annotated[int | None, Query(ge=0)] = None,
) -> Page[SmsOut]:
    """List SMS rows with optional filters, newest first."""
    conditions = []
    if user_id is not None:
        conditions.append(Sms.user_id == user_id)
    if start is not None:
        conditions.append(Sms.create_time >= start)
    if end is not None:
        conditions.append(Sms.create_time <= end)

    total_stmt = sa.select(sa.func.count()).select_from(Sms)
    if conditions:
        total_stmt = total_stmt.where(*conditions)
    total = (await session.execute(total_stmt)).scalar_one()

    list_stmt = sa.select(Sms)
    if conditions:
        list_stmt = list_stmt.where(*conditions)
    list_stmt = (
        list_stmt.order_by(
            sa.nullslast(Sms.create_time.desc()),
            Sms.sms_id.asc(),
        )
        .limit(page_size)
        .offset((page - 1) * page_size)
    )
    rows = (await session.execute(list_stmt)).scalars().all()
    items = [SmsOut.model_validate(row) for row in rows]
    return Page(items=items, total=total, page=page, page_size=page_size)