from decimal import Decimal as D

from django.test import TestCase
from django.test.client import RequestFactory
import mock

from oscar.apps.offer import models, utils
from oscar.apps.order.utils import OrderCreator
from oscar.apps.shipping.repository import Repository
from oscar.apps.shipping.methods import FixedPrice
from oscar.test.basket import add_product
from oscar.test import factories


def create_offer():
    range = models.Range.objects.create(
        name="All products", includes_all_products=True)
    condition = models.CountCondition.objects.create(
        range=range,
        type=models.Condition.COUNT,
        value=1)
    benefit = models.ShippingFixedPriceBenefit.objects.create(
        type=models.Benefit.SHIPPING_FIXED_PRICE,
        value=D('1.00'))
    return models.ConditionalOffer.objects.create(
        condition=condition,
        benefit=benefit,
        offer_type=models.ConditionalOffer.SITE)


def apply_offers(basket):
    req = RequestFactory().get('/')
    req.user = mock.Mock()
    utils.Applicator().apply(req, basket)


class StubRepository(Repository):
    """
    Stubbed shipped repository which overrides the get_shipping_methods method
    in order to use a non-free default shipping method.  This allows the
    shipping discounts to be tested.
    """
    methods = [FixedPrice(D('10.00'), D('10.00'))]


class TestAnOfferWithAShippingBenefit(TestCase):

    def setUp(self):
        self.basket = factories.create_basket(empty=True)
        create_offer()

    def test_applies_correctly_to_basket_which_matches_condition(self):
        add_product(self.basket, D('12.00'))
        apply_offers(self.basket)
        self.assertEqual(1, len(self.basket.offer_applications))

    def test_applies_correctly_to_basket_which_exceeds_condition(self):
        add_product(self.basket, D('12.00'), 2)
        apply_offers(self.basket)
        self.assertEqual(1, len(self.basket.offer_applications))

    def test_wraps_shipping_method_from_repository(self):
        add_product(self.basket, D('12.00'), 1)
        apply_offers(self.basket)
        methods = StubRepository().get_shipping_methods(self.basket)
        method = methods[0]

        charge = method.calculate(self.basket)
        self.assertEqual(D('1.00'), charge.incl_tax)

    def test_has_discount_recorded_correctly_when_order_is_placed(self):
        add_product(self.basket, D('12.00'), 1)
        apply_offers(self.basket)
        methods = StubRepository().get_shipping_methods(self.basket)
        method = methods[0]
        order = factories.create_order(basket=self.basket,
                                       shipping_method=method)

        discounts = order.discounts.all()
        self.assertEqual(1, len(discounts))

        discount = discounts[0]
        self.assertTrue(discount.is_shipping_discount)
        self.assertEqual(D('9.00'), discount.amount)