import datetime

import pytest
from django.utils import timezone
from django.utils.datastructures import MultiValueDict

from oscar.apps.dashboard.vouchers import forms
from oscar.core.loading import get_model
from oscar.test.factories.offer import (
    BenefitFactory, ConditionalOfferFactory, ConditionFactory, RangeFactory)
from oscar.test.factories.voucher import VoucherSetFactory

ConditionalOffer = get_model('offer', 'ConditionalOffer')
Voucher = get_model('voucher', 'Voucher')


@pytest.mark.django_db
def test_voucher_set_form_create():
    a_range = RangeFactory(
        includes_all_products=True
    )
    offer = ConditionalOfferFactory(offer_type=ConditionalOffer.VOUCHER,
                                    benefit=BenefitFactory(range=a_range),
                                    condition=ConditionFactory(range=a_range, value=1))
    data = MultiValueDict({
        'name': ['10% Discount'],
        'code_length': ['10'],
        'count': ['10'],
        'description': ['This is a 10% discount for mailing X'],
        'start_datetime': ['2014-10-01'],
        'end_datetime': ['2018-10-01'],
        'usage': [Voucher.MULTI_USE],
        'offers': [offer.pk],
    })
    form = forms.VoucherSetForm(data)
    assert form.is_valid(), form.errors
    voucher_set = form.save()
    assert voucher_set.vouchers.count() == 10


@pytest.mark.django_db
def test_voucher_set_form_update_with_unchanged_count():
    tzinfo = timezone.get_current_timezone()
    voucher_set = VoucherSetFactory(name="Dummy name",
                                    count=5,
                                    code_length=12,
                                    description="Dummy description",
                                    start_datetime=datetime.datetime(2021, 2, 1, tzinfo=tzinfo),
                                    end_datetime=datetime.datetime(2021, 2, 28, tzinfo=tzinfo))
    voucher = voucher_set.vouchers.first()
    assert voucher.usage == Voucher.MULTI_USE
    new_offers = [ConditionalOfferFactory(offer_type=ConditionalOffer.VOUCHER),
                  ConditionalOfferFactory(offer_type=ConditionalOffer.VOUCHER)]
    data = {
        'name': "New name",
        'code_length': 10,
        'description': "New description",
        'start_datetime': datetime.datetime(2021, 3, 1, tzinfo=tzinfo),
        'end_datetime': datetime.datetime(2021, 3, 31, tzinfo=tzinfo),
        'count': voucher_set.count,
        'usage': Voucher.SINGLE_USE,
        'offers': new_offers,
    }
    form = forms.VoucherSetForm(data, instance=voucher_set)
    assert form.is_valid(), form.errors
    voucher_set = form.save()
    assert voucher_set.vouchers.count() == 5
    for i, v in enumerate(voucher_set.vouchers.order_by('date_created')):
        assert v.name == "New name - %d" % (i + 1)
        assert len(v.code) == 14  # The code is not modified
        assert v.start_datetime == datetime.datetime(2021, 3, 1, tzinfo=tzinfo)
        assert v.end_datetime == datetime.datetime(2021, 3, 31, tzinfo=tzinfo)
        assert v.usage == Voucher.SINGLE_USE
        assert list(v.offers.all()) == new_offers


@pytest.mark.django_db
def test_voucher_set_form_update_with_changed_count():
    tzinfo = timezone.get_current_timezone()
    voucher_set = VoucherSetFactory(name="Dummy name",
                                    count=5,
                                    code_length=12,
                                    description="Dummy description",
                                    start_datetime=datetime.datetime(2021, 2, 1, tzinfo=tzinfo),
                                    end_datetime=datetime.datetime(2021, 2, 28, tzinfo=tzinfo))
    voucher = voucher_set.vouchers.first()
    assert voucher.usage == Voucher.MULTI_USE
    new_offers = [ConditionalOfferFactory(offer_type=ConditionalOffer.VOUCHER),
                  ConditionalOfferFactory(offer_type=ConditionalOffer.VOUCHER)]
    data = {
        'name': "New name",
        'code_length': 10,
        'description': "New description",
        'start_datetime': datetime.datetime(2021, 3, 1, tzinfo=tzinfo),
        'end_datetime': datetime.datetime(2021, 3, 31, tzinfo=tzinfo),
        'count': 10,
        'usage': Voucher.SINGLE_USE,
        'offers': new_offers,
    }
    form = forms.VoucherSetForm(data, instance=voucher_set)
    assert form.is_valid(), form.errors
    voucher_set = form.save()
    voucher_set.refresh_from_db()
    assert voucher_set.count == 10  # "count" is updated
    assert voucher_set.vouchers.count() == 10
    for i, v in enumerate(voucher_set.vouchers.order_by('date_created')):
        assert v.name == "New name - %d" % (i + 1)
        if i < 5:
            # Original vouchers
            assert len(v.code) == 14  # The code is not modified
        else:
            # New vouchers
            assert len(v.code) == 12
        assert v.start_datetime == datetime.datetime(2021, 3, 1, tzinfo=tzinfo)
        assert v.end_datetime == datetime.datetime(2021, 3, 31, tzinfo=tzinfo)
        assert v.usage == Voucher.SINGLE_USE
        assert list(v.offers.all()) == new_offers