"""Kleine gemeinsame Helfer für Router."""

from __future__ import annotations

from fastapi import HTTPException, status
from sqlalchemy.orm import Session

from .models import Product
from .schemas import ProductOut
from .services.stock import current_stock


def product_to_out(db: Session, product: Product) -> ProductOut:
    out = ProductOut.model_validate(product)
    out.stock = current_stock(db, product.id)
    return out


def resolve_product(
    db: Session, product_id: int | None, barcode: str | None
) -> Product:
    """Findet ein Produkt per ID oder Barcode; wirft 404, wenn keins passt."""
    product: Product | None = None
    if product_id is not None:
        product = db.get(Product, product_id)
    elif barcode:
        product = db.query(Product).filter(Product.barcode == barcode).first()
    else:
        raise HTTPException(
            status.HTTP_400_BAD_REQUEST, "product_id oder barcode erforderlich"
        )
    if product is None:
        raise HTTPException(status.HTTP_404_NOT_FOUND, "Produkt nicht gefunden")
    return product