from sqlalchemy import select
from sqlalchemy.orm import Session

from backend.app.models.business import Product, ProductCategory


class ProductRepository:
    def list_categories(self, session: Session, filters: dict) -> list[ProductCategory]:
        stmt = select(ProductCategory).where(ProductCategory.deleted == 0)

        if filters.get("category_name"):
            stmt = stmt.where(ProductCategory.category_name.contains(filters["category_name"]))
        if filters.get("status") is not None:
            stmt = stmt.where(ProductCategory.status == filters["status"])

        stmt = stmt.order_by(ProductCategory.sort_no.asc(), ProductCategory.id.asc())
        return list(session.execute(stmt).scalars())

    def get_category(self, session: Session, category_id: int) -> ProductCategory | None:
        stmt = select(ProductCategory).where(ProductCategory.id == category_id, ProductCategory.deleted == 0)
        return session.execute(stmt).scalar_one_or_none()

    def get_category_by_code(self, session: Session, category_code: str) -> ProductCategory | None:
        stmt = select(ProductCategory).where(
            ProductCategory.category_code == category_code,
            ProductCategory.deleted == 0,
        )
        return session.execute(stmt).scalar_one_or_none()

    def create_category(self, session: Session, payload: dict) -> ProductCategory:
        category = ProductCategory(**payload)
        session.add(category)
        session.flush()
        return category

    def update_category(self, session: Session, category: ProductCategory, payload: dict) -> ProductCategory:
        for key, value in payload.items():
            setattr(category, key, value)
        session.add(category)
        session.flush()
        return category

    def list_products(self, session: Session, filters: dict) -> list[Product]:
        stmt = select(Product).where(Product.deleted == 0)

        if filters.get("product_name"):
            stmt = stmt.where(Product.product_name.contains(filters["product_name"]))
        if filters.get("specification"):
            stmt = stmt.where(Product.specification.contains(filters["specification"]))
        if filters.get("category_id") is not None:
            stmt = stmt.where(Product.category_id == filters["category_id"])
        if filters.get("status") is not None:
            stmt = stmt.where(Product.status == filters["status"])

        stmt = stmt.order_by(Product.id.desc())
        return list(session.execute(stmt).scalars())

    def get_product(self, session: Session, product_id: int) -> Product | None:
        stmt = select(Product).where(Product.id == product_id, Product.deleted == 0)
        return session.execute(stmt).scalar_one_or_none()

    def get_product_by_name_and_specification(
        self,
        session: Session,
        product_name: str,
        specification: str,
    ) -> Product | None:
        stmt = select(Product).where(
            Product.product_name == product_name,
            Product.specification == specification,
            Product.deleted == 0,
        )
        return session.execute(stmt).scalar_one_or_none()

    def create_product(self, session: Session, payload: dict) -> Product:
        product = Product(**payload)
        session.add(product)
        session.flush()
        return product