from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.future import select
from typing import List

from database import get_db
from models import Notification, User
from schemas import NotificationResponse
from routers.auth_router import get_current_active_user

router = APIRouter(prefix="/api/v1/notifications", tags=["Notifications"])

@router.get("", response_model=List[NotificationResponse])
async def get_notifications(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    stmt = select(Notification).where(
        Notification.user_id == current_user.id
    ).order_by(Notification.created_at.desc()).limit(50)
    
    result = await db.execute(stmt)
    notifications = result.scalars().all()
    return notifications

@router.get("/unread/count")
async def get_unread_count(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    stmt = select(Notification).where(
        Notification.user_id == current_user.id,
        Notification.is_read == False
    )
    result = await db.execute(stmt)
    count = len(result.scalars().all())
    return {"count": count}

@router.put("/{notification_id}/read", response_model=NotificationResponse)
async def mark_as_read(
    notification_id: int,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    stmt = select(Notification).where(
        Notification.id == notification_id,
        Notification.user_id == current_user.id
    )
    result = await db.execute(stmt)
    notification = result.scalar_one_or_none()
    
    if not notification:
        raise HTTPException(status_code=404, detail="Notification not found")
        
    notification.is_read = True
    await db.commit()
    await db.refresh(notification)
    return notification

@router.put("/read-all")
async def mark_all_as_read(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_active_user)
):
    stmt = select(Notification).where(
        Notification.user_id == current_user.id,
        Notification.is_read == False
    )
    result = await db.execute(stmt)
    notifications = result.scalars().all()
    
    for notif in notifications:
        notif.is_read = True
        
    await db.commit()
    return {"status": "ok", "marked": len(notifications)}