Add a maximum budget to vouchers (#1526)

* Data model changes

* Fix test failures

* Adjustments

* Some tests and API support

* Check when extending orders

* Make things more deterministic, fix style

* Do not apply negative discounts

* Update price_before_voucher on item/subevent changes

* Add tests for price_before_voucher in combination with free price

* Fix InvoiceAddress.DoesNotExist

src/tests/api/test_orders.py

@@ -3105,6 +3105,81 @@ def test_order_create_auto_pricing_reverse_charge_require_valid_vatid(token_clie
     assert p.tax_rate == Decimal('19.00')
 
 
+@pytest.mark.django_db
+def test_order_create_autopricing_voucher_budget_partially(token_client, organizer, event, item, quota, question,
+                                                           taxrule):
+    with scopes_disabled():
+        voucher = event.vouchers.create(price_mode="set", value=21.50, item=item, budget=Decimal('2.50'),
+                                        max_usages=999)
+    res = copy.deepcopy(ORDER_CREATE_PAYLOAD)
+    res['positions'][0]['item'] = item.pk
+    res['positions'][0]['answers'][0]['question'] = question.pk
+    res['positions'][0]['voucher'] = voucher.code
+    del res['positions'][0]['price']
+    del res['positions'][0]['positionid']
+    res['positions'].append(res['positions'][0])
+
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/orders/'.format(
+            organizer.slug, event.slug
+        ), format='json', data=res
+    )
+    print(resp.data)
+    assert resp.status_code == 201
+    with scopes_disabled():
+        o = Order.objects.get(code=resp.data['code'])
+        p = o.positions.first()
+        p2 = o.positions.last()
+    assert p.price == Decimal('21.50')
+    assert p2.price == Decimal('22.00')
+
+
+@pytest.mark.django_db
+def test_order_create_autopricing_voucher_budget_full(token_client, organizer, event, item, quota, question, taxrule):
+    with scopes_disabled():
+        voucher = event.vouchers.create(price_mode="set", value=21.50, item=item, budget=Decimal('0.50'),
+                                        max_usages=999)
+    res = copy.deepcopy(ORDER_CREATE_PAYLOAD)
+    res['positions'][0]['item'] = item.pk
+    res['positions'][0]['answers'][0]['question'] = question.pk
+    res['positions'][0]['voucher'] = voucher.code
+    del res['positions'][0]['price']
+    del res['positions'][0]['positionid']
+    res['positions'].append(res['positions'][0])
+
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/orders/'.format(
+            organizer.slug, event.slug
+        ), format='json', data=res
+    )
+    assert resp.status_code == 400
+    assert resp.data == {'positions': [{}, {'voucher': ['The voucher has a remaining budget of 0.00, therefore a '
+                                                        'discount of 1.50 can not be given.']}]}
+
+
+@pytest.mark.django_db
+def test_order_create_voucher_budget_exceeded(token_client, organizer, event, item, quota, question, taxrule):
+    with scopes_disabled():
+        voucher = event.vouchers.create(price_mode="set", value=21.50, item=item, budget=Decimal('3.00'),
+                                        max_usages=999)
+    res = copy.deepcopy(ORDER_CREATE_PAYLOAD)
+    res['positions'][0]['item'] = item.pk
+    res['positions'][0]['answers'][0]['question'] = question.pk
+    res['positions'][0]['voucher'] = voucher.code
+    res['positions'][0]['price'] = '19.00'
+    del res['positions'][0]['positionid']
+
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/orders/'.format(
+            organizer.slug, event.slug
+        ), format='json', data=res
+    )
+    print(resp.data)
+    assert resp.status_code == 400
+    assert resp.data == {'positions': [{'voucher': ['The voucher has a remaining budget of 3.00, therefore a '
+                                                    'discount of 4.00 can not be given.']}]}
+
+
 @pytest.mark.django_db
 def test_order_create_voucher_price(token_client, organizer, event, item, quota, question):
     res = copy.deepcopy(ORDER_CREATE_PAYLOAD)

src/tests/base/test_models.py

@@ -795,6 +795,31 @@ class VoucherTestCase(BaseQuotaTestCase):
         v = Voucher.objects.create(event=self.event, price_mode='percent', value=Decimal('23.00'))
         assert v.calculate_price(Decimal('100.00')) == Decimal('77.00')
 
+    @classscope(attr='o')
+    def test_calculate_price_max_discount(self):
+        v = Voucher.objects.create(event=self.event, price_mode='subtract', value=Decimal('10.00'))
+        assert v.calculate_price(Decimal('23.42'), max_discount=Decimal('5.00')) == Decimal('18.42')
+
+    @classscope(attr='o')
+    def test_calculate_budget_used(self):
+        v = Voucher.objects.create(event=self.event, price_mode='sset', value=Decimal('20.00'))
+
+        order = Order.objects.create(
+            status=Order.STATUS_PENDING, event=self.event,
+            datetime=now() - timedelta(days=5), expires=now() + timedelta(days=5), total=46,
+        )
+        OrderPosition.objects.create(order=order, item=self.item1, voucher=v, price=Decimal('20.00'),
+                                     price_before_voucher=Decimal('23.00'))
+        assert v.budget_used() == Decimal('3.00')
+
+        order = Order.objects.create(
+            status=Order.STATUS_PAID, event=self.event,
+            datetime=now() - timedelta(days=5), expires=now() + timedelta(days=5), total=46,
+        )
+        OrderPosition.objects.create(order=order, item=self.item1, voucher=v, price=Decimal('20.00'),
+                                     price_before_voucher=Decimal('23.00'))
+        assert v.budget_used() == Decimal('6.00')
+
 
 class OrderTestCase(BaseQuotaTestCase):
     def setUp(self):

src/tests/base/test_orders.py

@@ -878,6 +878,36 @@ class OrderChangeManagerTests(TestCase):
         assert self.op1.tax_value == Decimal('3.67')
         assert self.op1.tax_rule == self.shirt.tax_rule
 
+    @classscope(attr='o')
+    def test_change_item_change_price_before_voucher(self):
+        self.op1.voucher = self.event.vouchers.create(item=self.shirt, redeemed=1, price_mode='set', value='5.00')
+        self.op1.price = Decimal('5.00')
+        self.op1.price_before_voucher = Decimal('23.00')
+        self.op1.save()
+        p = self.op1.price
+        self.ocm.change_item(self.op1, self.shirt, None)
+        self.ocm.commit()
+        self.op1.refresh_from_db()
+        self.order.refresh_from_db()
+        assert self.op1.item == self.shirt
+        assert self.op1.price == p
+        assert self.op1.price_before_voucher == Decimal('12.00')
+
+    @classscope(attr='o')
+    def test_change_item_change_price_before_voucher_minimum_value(self):
+        self.op1.voucher = self.event.vouchers.create(item=self.shirt, redeemed=1, price_mode='set', value='20.00')
+        self.op1.price = Decimal('20.00')
+        self.op1.price_before_voucher = Decimal('23.00')
+        self.op1.save()
+        p = self.op1.price
+        self.ocm.change_item(self.op1, self.shirt, None)
+        self.ocm.commit()
+        self.op1.refresh_from_db()
+        self.order.refresh_from_db()
+        assert self.op1.item == self.shirt
+        assert self.op1.price == p
+        assert self.op1.price_before_voucher == Decimal('20.00')
+
     @classscope(attr='o')
     def test_change_item_success(self):
         self.ocm.change_item(self.op1, self.shirt, None)

src/tests/control/test_orders.py

@@ -845,6 +845,69 @@ def test_order_extend_expired_quota_partial(client, env):
     assert o.status == Order.STATUS_EXPIRED
 
 
+@pytest.mark.django_db
+def test_order_extend_expired_voucher_budget_ok(client, env):
+    with scopes_disabled():
+        o = Order.objects.get(id=env[2].id)
+        o.expires = now() - timedelta(days=5)
+        o.status = Order.STATUS_EXPIRED
+        o.save()
+        v = env[0].vouchers.create(
+            code="foo", price_mode='subtract', value=Decimal('1.50'), budget=Decimal('1.50')
+        )
+        p = o.positions.first()
+        p.voucher = v
+        p.price_before_voucher = p.price
+        p.price -= Decimal('1.50')
+        p.save()
+
+        q = Quota.objects.create(event=env[0], size=100)
+        q.items.add(env[3])
+        newdate = (now() + timedelta(days=20)).strftime("%Y-%m-%d %H:%M:%S")
+    client.login(email='dummy@dummy.dummy', password='dummy')
+    response = client.post('/control/event/dummy/dummy/orders/FOO/extend', {
+        'expires': newdate
+    }, follow=True)
+    assert b'alert-success' in response.content
+    with scopes_disabled():
+        o = Order.objects.get(id=env[2].id)
+        assert o.status == Order.STATUS_PENDING
+        assert v.budget_used() == Decimal('1.50')
+
+
+@pytest.mark.django_db
+def test_order_extend_expired_voucher_budget_fail(client, env):
+    with scopes_disabled():
+        o = Order.objects.get(id=env[2].id)
+        o.expires = now() - timedelta(days=5)
+        o.status = Order.STATUS_EXPIRED
+        olddate = o.expires
+        o.save()
+        v = env[0].vouchers.create(
+            code="foo", price_mode='subtract', value=Decimal('1.50'), budget=Decimal('0.00')
+        )
+        p = o.positions.first()
+        p.voucher = v
+        p.price_before_voucher = p.price
+        p.price -= Decimal('1.50')
+        p.save()
+
+        q = Quota.objects.create(event=env[0], size=100)
+        q.items.add(env[3])
+        newdate = (now() + timedelta(days=20)).strftime("%Y-%m-%d %H:%M:%S")
+    client.login(email='dummy@dummy.dummy', password='dummy')
+    response = client.post('/control/event/dummy/dummy/orders/FOO/extend', {
+        'expires': newdate
+    }, follow=True)
+    assert b'alert-danger' in response.content
+    assert b'The voucher "FOO" no longer has sufficient budget.' in response.content
+    with scopes_disabled():
+        o = Order.objects.get(id=env[2].id)
+        assert o.expires.strftime("%Y-%m-%d %H:%M:%S") == olddate.strftime("%Y-%m-%d %H:%M:%S")
+        assert o.status == Order.STATUS_EXPIRED
+        assert v.budget_used() == Decimal('0.00')
+
+
 @pytest.mark.django_db
 def test_order_mark_paid_overdue_quota_blocked_by_waiting_list(client, env):
     with scopes_disabled():

src/tests/presale/test_cart.py

@@ -1388,6 +1388,32 @@ class CartTest(CartTestMixin, TestCase):
         self.assertEqual(objs[0].item, self.ticket)
         self.assertIsNone(objs[0].variation)
         self.assertEqual(objs[0].price, Decimal('21.00'))
+        self.assertEqual(objs[0].price_before_voucher, Decimal('23.00'))
+
+    def test_voucher_free_price_before_voucher_cap(self):
+        with scopes_disabled():
+            v = Voucher.objects.create(item=self.ticket, value=Decimal('10.00'), price_mode='percent', event=self.event)
+        self.ticket.free_price = True
+        self.ticket.save()
+        response = self.client.post('/%s/%s/cart/add' % (self.orga.slug, self.event.slug), {
+            'item_%d' % self.ticket.id: '1',
+            'price_%d' % self.ticket.id: '41.00',
+            '_voucher_code': v.code,
+        }, follow=True)
+        self.assertRedirects(response, '/%s/%s/?require_cookie=true' % (self.orga.slug, self.event.slug),
+                             target_status_code=200)
+        doc = BeautifulSoup(response.rendered_content, "lxml")
+        self.assertIn('Early-bird', doc.select('.cart .cart-row')[0].select('strong')[0].text)
+        self.assertIn('1', doc.select('.cart .cart-row')[0].select('.count')[0].text)
+        self.assertIn('41', doc.select('.cart .cart-row')[0].select('.price')[0].text)
+        self.assertIn('41', doc.select('.cart .cart-row')[0].select('.price')[1].text)
+        with scopes_disabled():
+            objs = list(CartPosition.objects.filter(cart_id=self.session_key, event=self.event))
+        self.assertEqual(len(objs), 1)
+        self.assertEqual(objs[0].item, self.ticket)
+        self.assertIsNone(objs[0].variation)
+        self.assertEqual(objs[0].price, Decimal('41.00'))
+        self.assertEqual(objs[0].price_before_voucher, Decimal('41.00'))
 
     def test_voucher_free_price_lower_bound(self):
         with scopes_disabled():
@@ -1412,6 +1438,7 @@ class CartTest(CartTestMixin, TestCase):
         self.assertEqual(objs[0].item, self.ticket)
         self.assertIsNone(objs[0].variation)
         self.assertEqual(objs[0].price, Decimal('20.70'))
+        self.assertEqual(objs[0].price_before_voucher, Decimal('23.00'))
 
     def test_voucher_redemed(self):
         with scopes_disabled():
@@ -2438,6 +2465,20 @@ class CartAddonTest(CartTestMixin, TestCase):
         assert cp2.expires > now()
         assert cp2.addon_to_id == cp1.pk
 
+    @classscope(attr='orga')
+    def test_expand_expired_refresh_voucher(self):
+        v = Voucher.objects.create(item=self.ticket, value=Decimal('20.00'), event=self.event, price_mode='set',
+                                   valid_until=now() + timedelta(days=2), max_usages=999, redeemed=0)
+        cp1 = CartPosition.objects.create(
+            expires=now() - timedelta(minutes=10), item=self.ticket, price=Decimal('21.50'),
+            event=self.event, cart_id=self.session_key, voucher=v
+        )
+        self.cm.extend_expired_positions()
+        self.cm.commit()
+        cp1.refresh_from_db()
+        assert cp1.expires > now()
+        assert cp1.price_before_voucher == Decimal('23.00')
+
 
 class CartBundleTest(CartTestMixin, TestCase):
     @scopes_disabled()
@@ -2490,6 +2531,30 @@ class CartBundleTest(CartTestMixin, TestCase):
         assert cp.price == 23 - 1.5
         assert cp.addons.count() == 1
         assert cp.voucher == v
+        assert cp.price_before_voucher == 23 - 1.5
+        a = cp.addons.get()
+        assert a.item == self.trans
+        assert a.price == 1.5
+        assert not a.voucher
+
+    @classscope(attr='orga')
+    def test_discounted_voucher_on_base_product(self):
+        v = self.event.vouchers.create(code="foo", item=self.ticket, price_mode='subtract', value=Decimal('1.50'))
+        self.cm.add_new_items([
+            {
+                'item': self.ticket.pk,
+                'variation': None,
+                'voucher': v.code,
+                'count': 1
+            }
+        ])
+        self.cm.commit()
+        cp = CartPosition.objects.get(addon_to__isnull=True)
+        assert cp.item == self.ticket
+        assert cp.price == 23 - 1.5 - 1.5
+        assert cp.addons.count() == 1
+        assert cp.voucher == v
+        assert cp.price_before_voucher == 23 - 1.5
         a = cp.addons.get()
         assert a.item == self.trans
         assert a.price == 1.5

src/tests/presale/test_checkout.py

@@ -3000,3 +3000,140 @@ class CheckoutSeatingTest(BaseCheckoutTestCase, TestCase):
         with self.assertRaises(OrderError):
             _perform_order(self.event, 'manual', [self.cp1.pk], 'admin@example.org', 'en', None, {}, 'web')
         assert not CartPosition.objects.filter(pk=self.cp1.pk).exists()
+
+
+class CheckoutVoucherBudgetTest(BaseCheckoutTestCase, TestCase):
+    @scopes_disabled()
+    def setUp(self):
+        super().setUp()
+        self.v = Voucher.objects.create(item=self.ticket, value=Decimal('21.50'), event=self.event, price_mode='set',
+                                        valid_until=now() + timedelta(days=2), max_usages=999, redeemed=0)
+        self.cp1 = CartPosition.objects.create(
+            event=self.event, cart_id=self.session_key, item=self.ticket,
+            price_before_voucher=23, price=21.5, expires=now() + timedelta(minutes=10), voucher=self.v
+        )
+        self.cp2 = CartPosition.objects.create(
+            event=self.event, cart_id=self.session_key, item=self.ticket,
+            price_before_voucher=23, price=21.5, expires=now() + timedelta(minutes=10), voucher=self.v
+        )
+
+    @scopes_disabled()
+    def test_no_budget(self):
+        oid = _perform_order(self.event, 'manual', [self.cp1.pk, self.cp2.pk], 'admin@example.org', 'en', None, {},
+                             'web')
+        o = Order.objects.get(pk=oid)
+        op = o.positions.first()
+        assert op.item == self.ticket
+        assert op.price_before_voucher == Decimal('23.00')
+
+    @scopes_disabled()
+    def test_budget_exceeded_for_second_order(self):
+        self.v.budget = Decimal('1.50')
+        self.v.save()
+        oid = _perform_order(self.event, 'manual', [self.cp1.pk], 'admin@example.org', 'en', None, {},
+                             'web')
+        o = Order.objects.get(pk=oid)
+        op = o.positions.first()
+        assert op.item == self.ticket
+
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('23.00')
+
+    @scopes_disabled()
+    def test_budget_exceeded_between_positions(self):
+        self.v.budget = Decimal('1.50')
+        self.v.save()
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp1.pk, self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp1.refresh_from_db()
+        assert self.cp1.price == Decimal('21.50')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('23.00')
+
+    @scopes_disabled()
+    def test_budget_exceeded_in_first_position(self):
+        self.v.budget = Decimal('1.00')
+        self.v.save()
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp1.pk, self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp1.refresh_from_db()
+        assert self.cp1.price == Decimal('22.00')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('23.00')
+
+    @scopes_disabled()
+    def test_budget_exceeded_in_second_position(self):
+        self.v.budget = Decimal('2.50')
+        self.v.save()
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp1.pk, self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp1.refresh_from_db()
+        assert self.cp1.price == Decimal('21.50')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('22.00')
+
+    @scopes_disabled()
+    def test_budget_exceeded_during_price_change(self):
+        self.v.budget = Decimal('2.50')
+        self.v.value = Decimal('21.00')
+        self.v.save()
+        self.cp1.expires = now() - timedelta(hours=1)
+        self.cp1.save()
+        self.cp2.expires = now() - timedelta(hours=1)
+        self.cp2.save()
+
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp1.pk, self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp1.refresh_from_db()
+        assert self.cp1.price == Decimal('21.00')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('22.50')
+
+    @scopes_disabled()
+    def test_budget_exceeded_expired_cart(self):
+        self.v.budget = Decimal('0.00')
+        self.v.value = Decimal('21.00')
+        self.v.save()
+        self.cp1.expires = now() - timedelta(hours=1)
+        self.cp1.save()
+        self.cp2.expires = now() - timedelta(hours=1)
+        self.cp2.save()
+
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp1.pk, self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp1.refresh_from_db()
+        assert self.cp1.price == Decimal('23.00')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('23.00')
+
+    @scopes_disabled()
+    def test_budget_overbooked_expired_cart(self):
+        self.v.budget = Decimal('1.50')
+        self.v.value = Decimal('21.50')
+        self.v.save()
+        self.cp1.expires = now() - timedelta(hours=1)
+        self.cp1.save()
+        self.cp2.expires = now() - timedelta(hours=1)
+        self.cp2.save()
+        oid = _perform_order(self.event, 'manual', [self.cp1.pk], 'admin@example.org', 'en', None, {},
+                             'web')
+        o = Order.objects.get(pk=oid)
+        op = o.positions.first()
+
+        assert op.item == self.ticket
+        self.v.budget = Decimal('1.00')
+        self.v.save()
+
+        with self.assertRaises(OrderError):
+            _perform_order(self.event, 'manual', [self.cp2.pk], 'admin@example.org', 'en', None, {},
+                           'web')
+        self.cp2.refresh_from_db()
+        assert self.cp2.price == Decimal('23.00')