from __future__ import annotations

from typing import Optional

from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from models.market import Product, ProductLike


def massage_full_product(product: Product) -> dict:
    """
    Convert a Product ORM model to a dictionary with all fields.
    Used for rendering product detail pages.
    """
    from bp.browse.services import _massage_product

    gallery = []
    if product.image:
        gallery.append(product.image)

    d = {
        "id": product.id,
        "slug": product.slug,
        "title": product.title,
        "brand": product.brand,
        "image": product.image,
        "description_short": product.description_short,
        "description_html": product.description_html or "",
        "suma_href": product.suma_href,
        "rrp": float(product.rrp) if product.rrp else None,
        "special_price": float(product.special_price) if product.special_price else None,
        "regular_price": float(product.regular_price) if product.regular_price else None,
        "images": gallery or [img.url for img in product.images],
        "all_image_urls": gallery or [img.url for img in product.images],
        "sections": [{"title": s.title, "html": s.html} for s in product.sections],
        "stickers": [s.name.lower() for s in product.stickers],
        "labels": [l.name for l in product.labels],
        "nutrition": [{"key": n.key, "value": n.value, "unit": n.unit} for n in product.nutrition],
        "allergens": [{"name": a.name, "contains": a.contains} for a in product.allergens],
        "is_liked": False,
    }

    return _massage_product(d)


async def toggle_product_like(
    session: AsyncSession,
    user_id: int,
    product_slug: str,
) -> tuple[bool, Optional[str]]:
    """
    Toggle a product like for a given user using soft deletes.
    Returns (liked_state, error_message).
    - If error_message is not None, an error occurred.
    - liked_state indicates whether product is now liked (True) or unliked (False).
    """
    from sqlalchemy import func, update

    # Get product_id from slug
    product_id = await session.scalar(
        select(Product.id).where(Product.slug == product_slug, Product.deleted_at.is_(None))
    )
    if not product_id:
        return False, "Product not found"

    # Check if like exists (not deleted)
    existing = await session.scalar(
        select(ProductLike).where(
            ProductLike.user_id == user_id,
            ProductLike.product_slug == product_slug,
            ProductLike.deleted_at.is_(None),
        )
    )

    if existing:
        # Unlike: soft delete the like
        await session.execute(
            update(ProductLike)
            .where(
                ProductLike.user_id == user_id,
                ProductLike.product_slug == product_slug,
                ProductLike.deleted_at.is_(None),
            )
            .values(deleted_at=func.now())
        )
        return False, None
    else:
        # Like: add a new like
        new_like = ProductLike(
            user_id=user_id,
            product_slug=product_slug,
        )
        session.add(new_like)
        return True, None