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

from app.dependencies import get_current_user, get_db
from app.models.object import Object
from app.models.zone import Zone
from app.models.user import User
from app.schemas.zone import ZoneCreate, ZoneRead, ZoneUpdate

router = APIRouter(prefix="/api/v1/objects/{obj_id}/zones", tags=["zones"])


async def _get_object(db: AsyncSession, obj_id: int) -> Object:
    obj = await db.get(Object, obj_id)
    if obj is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Object not found")
    return obj


async def _get_zone(db: AsyncSession, obj_id: int, zone_id: int) -> Zone:
    result = await db.execute(
        select(Zone).where(Zone.id == zone_id, Zone.object_id == obj_id)
    )
    zone = result.scalar_one_or_none()
    if zone is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Zone not found")
    return zone


@router.get("", response_model=list[ZoneRead])
async def list_zones(
    obj_id: int,
    db: AsyncSession = Depends(get_db),
    _: User = Depends(get_current_user),
):
    await _get_object(db, obj_id)
    result = await db.execute(
        select(Zone).where(Zone.object_id == obj_id).order_by(Zone.name)
    )
    return result.scalars().all()


@router.post("", response_model=ZoneRead, status_code=status.HTTP_201_CREATED)
async def create_zone(
    obj_id: int,
    body: ZoneCreate,
    db: AsyncSession = Depends(get_db),
    _: User = Depends(get_current_user),
):
    await _get_object(db, obj_id)
    zone = Zone(object_id=obj_id, **body.model_dump())
    db.add(zone)
    await db.flush()
    await db.refresh(zone)
    return zone


@router.patch("/{zone_id}", response_model=ZoneRead)
async def update_zone(
    obj_id: int,
    zone_id: int,
    body: ZoneUpdate,
    db: AsyncSession = Depends(get_db),
    _: User = Depends(get_current_user),
):
    zone = await _get_zone(db, obj_id, zone_id)
    for field, value in body.model_dump(exclude_none=True).items():
        setattr(zone, field, value)
    await db.flush()
    await db.refresh(zone)
    return zone


@router.delete("/{zone_id}", status_code=status.HTTP_204_NO_CONTENT)
async def delete_zone(
    obj_id: int,
    zone_id: int,
    db: AsyncSession = Depends(get_db),
    _: User = Depends(get_current_user),
):
    zone = await _get_zone(db, obj_id, zone_id)
    await db.delete(zone)