from fastapi import HTTPException
from sqlalchemy import select

from models.product import Product
from schemas.base import PaginationSchema
from services.base import BaseService
from schemas.product import *


class ProductService(BaseService):
    async def create(self, request: ProductCreateRequest) -> ProductCreateResponse:
        existing_product_query = await self.session.execute(
            select(Product)
            .where(Product.client_id == request.client_id,
                   Product.article == request.article)
        )
        existing_product = existing_product_query.first()
        if existing_product:
            raise HTTPException(status_code=403, detail="Product already exists")
        product = Product(**request.dict())
        self.session.add(product)
        await self.session.commit()
        return ProductCreateResponse(product_id=product.id)

    async def get_by_client_id(self, client_id: int, pagination: PaginationSchema) -> ProductGetResponse:
        query = await self.session.execute(
            select(Product)
            .where(Product.client_id == client_id)
            .offset(pagination.page * pagination.items_per_page)
            .limit(pagination.items_per_page)
        )
        products: list[ProductSchema] = []
        for product in query.scalars().all():
            products.append(
                ProductSchema.model_validate(product)
            )
        return ProductGetResponse(products=products)