Source code for shuup.campaigns.models.product_effects

# This file is part of Shuup.
#
# Copyright (c) 2012-2021, Shuup Commerce Inc. All rights reserved.
#
# This source code is licensed under the OSL-3.0 license found in the
# LICENSE file in the root directory of this source tree.
from django.db import models
from django.utils.translation import ugettext_lazy as _

from shuup.admin.forms.fields import PercentageField
from shuup.core.fields import MoneyValueField
from shuup.core.models import PolymorphicShuupModel


class ProductDiscountEffect(PolymorphicShuupModel):
    identifier = None
    model = None
    admin_form_class = None

    campaign = models.ForeignKey(
        on_delete=models.CASCADE, to="CatalogCampaign", related_name="effects", verbose_name=_("campaign")
    )

    def apply_for_product(self, context, product, price_info):
        """
        Applies the effect for product

        :type context: shuup.core.pricing._context.PricingContextable
        :return: amount of discount to accumulate for the product
        :rtype: Price
        """
        raise NotImplementedError("Error! Not implemented: `ProductDiscountEffect` -> `apply_for_product()`")


class ProductDiscountAmount(ProductDiscountEffect):
    identifier = "discount_amount_effect"
    name = _("Discount amount value")

    discount_amount = MoneyValueField(
        default=None, blank=True, null=True, verbose_name=_("discount amount"), help_text=_("Flat amount of discount.")
    )

    @property
    def description(self):
        return _("Give discount amount.")

    @property
    def value(self):
        return self.discount_amount

    @value.setter
    def value(self, value):
        self.discount_amount = value

    def apply_for_product(self, context, product, price_info):
        return price_info.price.new(self.value * price_info.quantity)


class ProductDiscountPercentage(ProductDiscountEffect):
    identifier = "discount_percentage_effect"
    name = _("Discount amount percentage")
    admin_form_class = PercentageField

    discount_percentage = models.DecimalField(
        max_digits=6,
        decimal_places=5,
        blank=True,
        null=True,
        verbose_name=_("discount percentage"),
        help_text=_("The discount percentage for this campaign."),
    )

    @property
    def description(self):
        return _("Give percentage discount.")

    @property
    def value(self):
        return self.discount_percentage

    @value.setter
    def value(self, value):
        self.discount_percentage = value

    def apply_for_product(self, context, product, price_info):
        return price_info.price * self.value