from typing import Sequence

from sqlalchemy import desc, func, select

from fooder.domain import Product, UserProductUsage
from fooder.repository.expression import fuzzy_match
from fooder.repository.base import RepositoryBase, DEFAULT_LIMIT


class ProductRepository(RepositoryBase[Product]):
    async def get_by_id(self, product_id: int) -> Product:
        return await self._get(Product.id == product_id)

    async def get_by_barcode(self, barcode: str) -> Product:
        return await self._get(Product.barcode == barcode)

    async def list(
        self,
        q: str | None = None,
        offset: int = 0,
        limit: int | None = DEFAULT_LIMIT,
    ) -> Sequence[Product]:
        expressions = (fuzzy_match(Product.name, q),) if q else ()
        return await self._list(*expressions, offset=offset, limit=limit)

    async def list_for_user(
        self,
        user_id: int,
        q: str | None = None,
        offset: int = 0,
        limit: int | None = DEFAULT_LIMIT,
    ):
        usage_label = "usage_count"
        usage_count = func.coalesce(UserProductUsage.count, 0).label(usage_label)
        expressions = (fuzzy_match(Product.name, q),) if q else ()

        stmt = (
            select(Product, usage_count)
            .outerjoin(
                UserProductUsage,
                (Product.id == UserProductUsage.product_id)
                & (UserProductUsage.user_id == user_id),
            )
            .order_by(desc(usage_label), Product.name)
        )
        return await self._list(*expressions, offset=offset, limit=limit, stmt=stmt)