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

from db.models import Category


class CategoriesRepository:
    async def get_category_by_id(
        self, session: AsyncSession, category_id: int
    ) -> Optional[Category]:
        stmt = select(Category).where(Category.id == category_id)
        return await session.scalar(stmt)

    async def get_category_by_parent_id(
        self, session: AsyncSession, parent_id: Optional[int] = None
    ) -> list[Category]:
        stmt = select(Category).where(Category.parent_id == parent_id)
        result = await session.scalars(stmt)

        return list(result)