"""通知 API 端点 — 获取列表、标记已读"""
from __future__ import annotations
import uuid
from fastapi import APIRouter, Depends, Query
from sqlalchemy import select, func
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.database import get_db
from app.models.notification import Notification
from app.schemas.notification import NotificationResponse, NotificationListResponse

router = APIRouter(prefix="/notifications", tags=["消息通知"])


@router.get("/", response_model=NotificationListResponse)
async def list_notifications(
    user_id: str = Query(..., description="当前用户ID"),
    skip: int = Query(0, ge=0),
    limit: int = Query(20, ge=1, le=100),
    db: AsyncSession = Depends(get_db),
):
    """获取当前用户的通知列表（按时间倒序）"""
    # 总数
    count_stmt = select(func.count()).select_from(Notification).where(
        Notification.user_id == user_id
    )
    total_result = await db.execute(count_stmt)
    total = total_result.scalar() or 0

    # 未读数
    unread_stmt = select(func.count()).select_from(Notification).where(
        Notification.user_id == user_id,
        Notification.is_read.is_(False),
    )
    unread_result = await db.execute(unread_stmt)
    unread_count = unread_result.scalar() or 0

    # 列表
    stmt = (
        select(Notification)
        .where(Notification.user_id == user_id)
        .order_by(Notification.created_at.desc())
        .offset(skip)
        .limit(limit)
    )
    result = await db.execute(stmt)
    notifications = result.scalars().all()

    return NotificationListResponse(
        notifications=[
            NotificationResponse.model_validate(n) for n in notifications
        ],
        total=total,
        unread_count=unread_count,
    )


@router.put("/{notification_id}/read", response_model=NotificationResponse)
async def mark_notification_read(
    notification_id: str,
    db: AsyncSession = Depends(get_db),
):
    """标记单条通知为已读"""
    nid = uuid.UUID(notification_id)
    result = await db.execute(
        select(Notification).where(Notification.id == nid)
    )
    notification = result.scalar_one_or_none()
    if not notification:
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=f"通知不存在: {notification_id}",
        )

    notification.is_read = True
    await db.commit()
    await db.refresh(notification)
    return NotificationResponse.model_validate(notification)