"""OpenFoodFacts proxy (spec §3.5). All OFF calls go through this router.

OFF etiquette (spec §8.1 rule 10): descriptive User-Agent, timeouts, and
kcal-vs-kJ normalization in exactly one module. Tests mock at the httpx
boundary — never hit the real OFF API (spec §8.4).

Routes:
  GET  /api/off/product/{barcode}   — lookup + normalize; 404 if not found
  GET  /api/off/search?q=           — search + normalize each hit; [] if none
  POST /api/off/refresh/{food_id}   — re-fetch by stored barcode, update row
"""

from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session

from database import get_db
from services.off import (
    NoBarcodeError,
    RefreshError,
    fetch_product,
    refresh_food,
    search_off,
)

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


@router.get("/product/{barcode}")
def get_product(barcode: str):
    """Look up a product by barcode on OpenFoodFacts and return normalized
    data matching our FoodCreate shape.

    Returns 404 when OFF has status=0, no product, or the product is
    unusable (no name and no computable calories).
    """
    result = fetch_product(barcode)
    if result is None:
        raise HTTPException(
            status_code=404, detail=f"Product not found for barcode: {barcode}"
        )
    return result


@router.get("/search")
def get_search(q: str = Query(..., min_length=1, description="Search query")):
    """Search OpenFoodFacts by text query. Returns a list of normalized
    food dicts (matching our FoodCreate shape). Empty list when nothing
    is found or all results are unusable.
    """
    return search_off(q)


@router.post("/refresh/{food_id}")
def post_refresh(food_id: int, db: Session = Depends(get_db)):
    """Re-fetch a food's data from OpenFoodFacts by its stored barcode,
    normalize, and update the local row (nutrition, name, brand, serving,
    off_data; bumps updated_at).

    404 — food_id not found, or OFF no longer has the product.
    400 — the food has no barcode (can't refresh).
    """
    try:
        return refresh_food(db, food_id)
    except RefreshError as e:
        raise HTTPException(status_code=e.status_code, detail=e.detail)
    except NoBarcodeError as e:
        raise HTTPException(status_code=e.status_code, detail=e.detail)