Source code for shuup.core.pricing._discounts

import abc
from typing import TYPE_CHECKING, Dict, Iterable, Union

import six

from shuup.apps.provides import load_module_instances

if TYPE_CHECKING:  # pragma: no cover
    from shuup.core.models import Product, ShopProduct
    from shuup.core.pricing import PriceInfo, PricingContext


def get_discount_modules():
    """
    Get a list of configured discount module instances.

    :rtype: list[DiscountModule]
    """
    return load_module_instances("SHUUP_DISCOUNT_MODULES", "discount_module")


class DiscountModule(six.with_metaclass(abc.ABCMeta)):


    @abc.abstractmethod
    def discount_price(
        self,
        context: "PricingContext",
        product: "Union[Product, int]",
        price_info: "PriceInfo",
    ) -> "PriceInfo":
        """
        Discount given price of given product.
        :param context: Pricing context to operate in
        :param product: Product in question or its id
        :param price_info: Price to discount
        :return: A new instance of a discounted price
        """
        return price_info




    def get_pricing_steps(
        self,
        context: "PricingContext",
        product: "Union[Product, int]",
        steps: "Iterable[PriceInfo]",
    ) -> "Iterable[PriceInfo]":
        """
        Get discounted pricing steps for given product.

        Base class version just discounts all the given steps with
        `discount_price`, but another module could add more steps and
        should do so, if the module introduces any pricing steps.

        :param context: Pricing context to operate in
        :type context: shuup.core.pricing.PricingContext
        :param product: Product in question or its id
        :type product: shuup.core.models.Product|int
        :type steps: list[PriceInfo]
        :rtype: list[PriceInfo]
        """
        return [self.discount_price(context, product, price_info) for price_info in steps]




    def discount_prices(
        self,
        context: "PricingContext",
        products: "Iterable[Union[Product, int]]",
        price_infos: "Dict[int, PriceInfo]",
    ) -> "Dict[int, PriceInfo]":
        """
        Discount a bunch of prices.

        :param context: Pricing context to operate in
        :type context: shuup.core.pricing.PricingContext
        :param products: Products in question or their ids
        :type products: Iterable[shuup.core.models.Product|int]
        :type price_infos: dict[int,PriceInfo]
        :rtype: dict[int,PriceInfo]
        """
        product_map = {getattr(x, "pk", x): x for x in products}
        return {
            pk: self.discount_price(context, product_map[pk], price_info)
            for (pk, price_info) in six.iteritems(price_infos)
        }




    def get_pricing_steps_for_products(
        self,
        context: "PricingContext",
        products: "Iterable[Union[Product, int]]",
        steps: "Iterable[PriceInfo]",
    ) -> "Dict[int, Iterable[PriceInfo]]":
        """
        Get discounted pricing steps for a bunch of products.

        :param context: Pricing context to operate in
        :type context: shuup.core.pricing.PricingContext
        :param products: Products in question or their ids
        :type products: Iterable[shuup.core.models.Product|int]
        :type steps: dict[int,list[PriceInfo]]
        :rtype: dict[int,list[PriceInfo]]
        """
        pks_and_products = ((getattr(x, "pk", x), x) for x in products)
        return {pk: self.get_pricing_steps(context, product, steps[pk]) for (pk, product) in pks_and_products}




    def index_shop_product(self, shop_product: Union["ShopProduct", int], **kwargs):
        """
        Index the shop product discounts
        """
        pass