from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.orm import Session, joinedload
from uuid import UUID
from backend.database import get_db
from backend import models
from backend.schemas import ItemCreate, ItemOut

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


@router.get("/", response_model=list[ItemOut])
def list_items(db: Session = Depends(get_db)):
    items = db.query(models.Item).options(joinedload(models.Item.tags)).all()
    return items


@router.post("/", response_model=ItemOut)
def create_item(payload: ItemCreate, db: Session = Depends(get_db)):
    # Demo: use first user or create one if none exists
    user = db.query(models.User).first()
    if not user:
        from uuid import uuid4
        user = models.User(id=uuid4(), name="Demo")
        db.add(user)
        db.flush()

    # Create the item
    item = models.Item(user_id=user.id, name=payload.name)

    # Attach tags if provided
    if payload.tag_ids:
        tags = (
            db.query(models.Tag)
            .filter(models.Tag.id.in_(payload.tag_ids), models.Tag.user_id == user.id)
            .all()
        )
        item.tags.extend(tags)

    db.add(item)
    db.commit()
    db.refresh(item)

    return item


@router.delete("/{item_id}", status_code=204)
def delete_item(item_id: UUID, db: Session = Depends(get_db)):
    item = db.get(models.Item, item_id)
    if not item:
        raise HTTPException(status_code=404, detail="Item not found")
    db.delete(item)
    db.commit()