Bank transfer: Improve refund handling (#3769)

src/pretix/plugins/banktransfer/tasks.py

@@ -32,6 +32,7 @@
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
 
+import json
 import logging
 import re
 from decimal import Decimal
@@ -42,13 +43,14 @@ from django.conf import settings
 from django.db import transaction
 from django.db.models import Max, Min, Q
 from django.db.models.functions import Length
+from django.utils.timezone import now
 from django.utils.translation import gettext_noop
 from django_scopes import scope, scopes_disabled
 
 from pretix.base.email import get_email_context
 from pretix.base.i18n import language
 from pretix.base.models import (
-    Event, Invoice, Order, OrderPayment, Organizer, Quota,
+    Event, Invoice, Order, OrderPayment, OrderRefund, Organizer, Quota,
 )
 from pretix.base.payment import PaymentException
 from pretix.base.services.locking import LockTimeoutException
@@ -194,6 +196,53 @@ def _handle_transaction(trans: BankTransaction, matches: tuple, event: Event = N
 
     trans.state = BankTransaction.STATE_VALID
     for order, amount in splits:
+        info_data = {
+            'reference': trans.reference,
+            'date': trans.date_parsed.isoformat() if trans.date_parsed else trans.date,
+            'payer': trans.payer,
+            'iban': trans.iban,
+            'bic': trans.bic,
+            'full_amount': str(trans.amount),
+            'trans_id': trans.pk
+        }
+        if amount < Decimal("0.00"):
+            pending_refund = order.refunds.filter(
+                amount=-amount,
+                provider__in=('manual', 'banktransfer'),
+                state__in=(OrderRefund.REFUND_STATE_CREATED, OrderRefund.REFUND_STATE_TRANSIT),
+            ).first()
+            existing_payment = order.payments.filter(
+                provider='banktransfer',
+                state__in=(OrderPayment.PAYMENT_STATE_CONFIRMED,),
+            ).first()
+            if pending_refund:
+                pending_refund.provider = "banktransfer"
+                pending_refund.info_data = {
+                    **pending_refund.info_data,
+                    **info_data,
+                }
+                pending_refund.done()
+            elif existing_payment:
+                existing_payment.create_external_refund(
+                    amount=-amount,
+                    info=json.dumps(info_data)
+                )
+            else:
+                r = order.refunds.create(
+                    state=OrderRefund.REFUND_STATE_EXTERNAL,
+                    source=OrderRefund.REFUND_SOURCE_EXTERNAL,
+                    amount=-amount,
+                    order=order,
+                    execution_date=now(),
+                    provider='banktransfer',
+                    info=json.dumps(info_data)
+                )
+                order.log_action('pretix.event.order.refund.created.externally', {
+                    'local_id': r.local_id,
+                    'provider': r.provider,
+                })
+            continue
+
         try:
             p, created = order.payments.get_or_create(
                 amount=amount,
@@ -213,13 +262,7 @@ def _handle_transaction(trans: BankTransaction, matches: tuple, event: Event = N
 
         p.info_data = {
             **p.info_data,
-            'reference': trans.reference,
-            'date': trans.date_parsed.isoformat() if trans.date_parsed else trans.date,
-            'payer': trans.payer,
-            'iban': trans.iban,
-            'bic': trans.bic,
-            'full_amount': str(trans.amount),
-            'trans_id': trans.pk
+            **info_data,
         }
 
         if created:

src/tests/plugins/banktransfer/test_import.py

@@ -43,8 +43,8 @@ from django.utils.timezone import now
 from django_scopes import scopes_disabled
 
 from pretix.base.models import (
-    Event, Item, Order, OrderFee, OrderPayment, OrderPosition, Organizer,
-    Quota, Team, User,
+    Event, Item, Order, OrderFee, OrderPayment, OrderPosition, OrderRefund,
+    Organizer, Quota, Team, User,
 )
 from pretix.base.services.invoices import generate_invoice
 from pretix.plugins.banktransfer.models import BankImportJob, BankTransaction
@@ -141,6 +141,11 @@ def orga_job(env):
     return BankImportJob.objects.create(organizer=env[0].organizer).pk
 
 
+@pytest.fixture
+def orga_job2(env):
+    return BankImportJob.objects.create(organizer=env[0].organizer).pk
+
+
 @pytest.mark.django_db
 def test_mark_paid(env, job):
     djmail.outbox = []
@@ -610,3 +615,81 @@ def test_pending_paypal_replace_fee_missing(env, job):
         assert env[2].fees.count() == 1
         assert env[2].fees.last().value == Decimal('1.00')
         assert env[2].total == Decimal('24.00')
+
+
+@pytest.mark.django_db
+def test_refund_handling_no_payments(env, orga_job):
+    process_banktransfers(orga_job, [{
+        'payer': 'Karla Kundin',
+        'reference': 'Bestellung DUMMY-1234S',
+        'date': '2016-01-26',
+        'amount': '-23.00'
+    }])
+    with scopes_disabled():
+        env[2].refresh_from_db()
+        assert env[2].status == Order.STATUS_PENDING
+        assert env[2].payments.count() == 0
+        r = env[2].refunds.get()
+        assert r.state == OrderRefund.REFUND_STATE_EXTERNAL
+        assert r.amount == Decimal("23.00")
+
+
+@pytest.mark.django_db
+def test_refund_handling_refund_for_payment(env, orga_job, orga_job2):
+    process_banktransfers(orga_job, [{
+        'payer': 'Karla Kundin',
+        'reference': 'Bestellung DUMMY-1234S',
+        'date': '2016-01-26',
+        'amount': '13.00'
+    }])
+    with scopes_disabled():
+        env[2].refresh_from_db()
+        assert env[2].status == Order.STATUS_PENDING
+        p = env[2].payments.get()
+
+    process_banktransfers(orga_job2, [{
+        'payer': 'Karla Kundin',
+        'reference': 'Erstattung DUMMY-1234S',
+        'date': '2016-01-27',
+        'amount': '-13.00'
+    }])
+    with scopes_disabled():
+        env[2].refresh_from_db()
+        assert env[2].status == Order.STATUS_PENDING
+        assert env[2].payments.count() == 1
+        r = env[2].refunds.get()
+        assert r.state == OrderRefund.REFUND_STATE_EXTERNAL
+        assert r.payment == p
+        assert r.amount == Decimal("13.00")
+
+
+@pytest.mark.django_db
+def test_refund_handling_pending_refund(env, orga_job, orga_job2):
+    process_banktransfers(orga_job, [{
+        'payer': 'Karla Kundin',
+        'reference': 'Bestellung DUMMY-1234S',
+        'date': '2016-01-26',
+        'amount': '23.00'
+    }])
+    with scopes_disabled():
+        env[2].refresh_from_db()
+        assert env[2].status == Order.STATUS_PAID
+        env[2].status = Order.STATUS_PENDING
+        env[2].save()
+        r = env[2].refunds.create(
+            state=OrderRefund.REFUND_STATE_CREATED,
+            provider="manual",
+            amount="23.00",
+        )
+
+    process_banktransfers(orga_job2, [{
+        'payer': 'Karla Kundin',
+        'reference': 'Erstattung DUMMY-1234S',
+        'date': '2016-01-27',
+        'amount': '-23.00'
+    }])
+    with scopes_disabled():
+        env[2].refresh_from_db()
+        r.refresh_from_db()
+        assert env[2].payments.count() == 1
+        assert r.state == OrderRefund.REFUND_STATE_DONE