basket: credit generation on validate with negative basket (#83457)

lingo/basket/migrations/0006_credit.py

@@ -0,0 +1,19 @@
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('invoicing', '0074_credit'),
+        ('basket', '0005_basket_expiry'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='basket',
+            name='credit',
+            field=models.ForeignKey(
+                null=True, on_delete=django.db.models.deletion.PROTECT, to='invoicing.credit'
+            ),
+        ),
+    ]

lingo/basket/models.py

@@ -24,7 +24,7 @@ from django.db import models, transaction
 from django.utils.timezone import now
 from django.utils.translation import gettext_lazy as _
 
-from lingo.invoicing.models import DraftInvoice, Invoice, Regie
+from lingo.invoicing.models import Credit, DraftInvoice, Invoice, Regie
 from lingo.utils.requests_wrapper import requests as requests_wrapper
 
 
@@ -34,6 +34,7 @@ class Basket(models.Model):
     regie = models.ForeignKey(Regie, on_delete=models.PROTECT)
     draft_invoice = models.ForeignKey(DraftInvoice, on_delete=models.PROTECT)
     invoice = models.ForeignKey(Invoice, on_delete=models.PROTECT, null=True)
+    credit = models.ForeignKey(Credit, on_delete=models.PROTECT, null=True)
 
     payer_nameid = models.CharField(max_length=250)
     payer_external_id = models.CharField(max_length=250)

lingo/basket/views.py

@@ -14,11 +14,14 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import datetime
+
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.http import Http404
 from django.shortcuts import get_object_or_404, redirect
 from django.urls import reverse
 from django.utils.timezone import now
+from django.utils.translation import gettext as _
 from django.views.generic import FormView, TemplateView, View
 
 from lingo.basket.models import Basket
@@ -79,12 +82,28 @@ class BasketValidateView(LoginRequiredMixin, FormView):
         return super().get_context_data(**kwargs)
 
     def post(self, request, *args, **kwargs):
+        if self.basket.draft_invoice.total_amount >= 0:
+            self.generate_invoice()
+        else:
+            self.generate_credit()
+        return redirect(reverse('lingo-basket-detail'))
+
+    def generate_invoice(self):
         self.basket.invoice = self.basket.draft_invoice.promote()
         self.basket.status = 'tobepaid'
         self.basket.validated_at = now()
         self.basket.save()
         self.basket.notify('validation')
-        return redirect(reverse('lingo-basket-detail'))
+
+    def generate_credit(self):
+        label = _('Credit from %s') % datetime.date.today().strftime('%d/%m/%Y')
+        self.basket.credit = self.basket.draft_invoice.promote_into_credit(label)
+        self.basket.status = 'completed'
+        self.basket.validated_at = now()
+        self.basket.completed_at = now()
+        self.basket.save()
+        self.basket.notify('validation')
+        self.basket.notify('credit')
 
 
 basket_validate = BasketValidateView.as_view()

lingo/invoicing/models.py

@@ -954,6 +954,22 @@ class DraftInvoice(AbstractInvoice):
 
         return final_invoice
 
+    def promote_into_credit(self, label):
+        credit = copy.deepcopy(self)
+        credit.__class__ = Credit
+        credit.pk = None
+        credit.uuid = uuid.uuid4()
+        credit.set_number()
+        credit.assigned_amount = 0
+        credit.remaining_amount = 0
+        credit.label = label
+        credit.save()
+
+        for line in self.lines.all().order_by('pk'):
+            line.promote_into_credit(credit=credit)
+
+        return credit
+
 
 class Invoice(AbstractInvoice):
     number = models.PositiveIntegerField(default=0)
@@ -1109,6 +1125,16 @@ class DraftInvoiceLine(AbstractInvoiceLine):
         for line in self.journal_lines.all().order_by('pk'):
             line.promote(pool=pool, invoice_line=final_line)
 
+    def promote_into_credit(self, credit=None):
+        credit_line = copy.deepcopy(self)
+        credit_line.__class__ = CreditLine
+        credit_line.pk = None
+        credit_line.credit = credit
+        credit_line.quantity = -self.quantity  # inverse quantities, so credit total_amout is positive
+        credit_line.assigned_amount = 0
+        credit_line.remaining_amount = 0
+        credit_line.save()
+
 
 class InvoiceLine(AbstractInvoiceLine):
     invoice = models.ForeignKey(Invoice, on_delete=models.PROTECT, null=True, related_name='lines')

tests/basket/test_basket.py

@@ -7,7 +7,7 @@ from django.utils.timezone import now
 from pyquery import PyQuery
 
 from lingo.basket.models import Basket, BasketLine, BasketLineItem
-from lingo.invoicing.models import DraftInvoice, Invoice, Regie
+from lingo.invoicing.models import Credit, DraftInvoice, DraftInvoiceLine, Invoice, Regie
 from tests.utils import login
 
 pytestmark = pytest.mark.django_db
@@ -261,6 +261,7 @@ def test_basket_validate(app, simple_user):
     assert Invoice.objects.count() == 1
     invoice = Invoice.objects.latest('pk')
     assert basket.invoice == invoice
+    assert basket.credit is None
 
     # wrong status
     for status in ['tobepaid', 'cancelled', 'expired', 'completed']:
@@ -272,12 +273,14 @@ def test_basket_validate(app, simple_user):
     basket.status = 'open'
     basket.save()
     line.validation_callback_url = 'http://validation1.com'
+    line.credit_callback_url = 'http://validation1.com'
     line.save()
     BasketLine.objects.create(
         basket=basket,
         closed=True,
         user_external_id='user:2',
         validation_callback_url='http://validation2.com',
+        credit_callback_url='http://validation2.com',
     )
     resp = app.get('/basket/validate/')
     with mock.patch('lingo.utils.requests_wrapper.RequestsSession.send') as mock_send:
@@ -294,6 +297,179 @@ def test_basket_validate(app, simple_user):
     app.get('/basket/validate/', status=404)
 
 
+def test_basket_validate_generate_invoice(app, simple_user):
+    app = login(app, username='user', password='user')
+
+    regie = Regie.objects.create(label='Foo')
+    draft_invoice = DraftInvoice.objects.create(
+        regie=regie,
+        date_publication=datetime.date(2023, 4, 21),
+        date_payment_deadline=datetime.date(2023, 4, 22),
+        date_due=datetime.date(2023, 4, 23),
+    )
+    DraftInvoiceLine.objects.create(
+        slug='event-a-foo-bar',
+        label='Event A',
+        event_date=datetime.date(2022, 9, 1),
+        invoice=draft_invoice,
+        quantity=1,
+        unit_amount=1,
+        user_external_id='user:1',
+    )
+    # invoice total amount is positive
+    draft_invoice.refresh_from_db()
+    assert draft_invoice.total_amount == 1
+    basket = Basket.objects.create(
+        regie=regie,
+        draft_invoice=draft_invoice,
+        payer_nameid='ab' * 16,
+        expiry_at=now() + datetime.timedelta(hours=1),
+    )
+    BasketLine.objects.create(
+        basket=basket,
+        closed=True,
+        user_external_id='user:1',
+        group_items=False,
+    )
+
+    resp = app.get('/basket/validate/')
+    resp = resp.form.submit()
+    assert resp.location.endswith('/basket/')
+    basket.refresh_from_db()
+    assert basket.status == 'tobepaid'
+    assert basket.validated_at is not None
+    assert basket.completed_at is None
+    invoice = Invoice.objects.latest('pk')
+    assert basket.invoice == invoice
+    assert invoice.total_amount == 1
+    assert Credit.objects.count() == 0
+
+    # total is zero
+    DraftInvoiceLine.objects.create(
+        slug='event-b-foo-bar',
+        label='Event B',
+        event_date=datetime.date(2022, 9, 1),
+        invoice=draft_invoice,
+        quantity=-1,
+        unit_amount=1,
+        user_external_id='user:1',
+    )
+    draft_invoice.refresh_from_db()
+    assert draft_invoice.total_amount == 0
+    basket.status = 'open'
+    basket.save()
+
+    resp = app.get('/basket/validate/')
+    resp = resp.form.submit()
+    assert resp.location.endswith('/basket/')
+    basket.refresh_from_db()
+    assert basket.status == 'tobepaid'
+    assert basket.validated_at is not None
+    assert basket.completed_at is None
+    invoice = Invoice.objects.latest('pk')
+    assert basket.invoice == invoice
+    assert invoice.total_amount == 0
+    assert Credit.objects.count() == 0
+
+
+def test_basket_validate_generate_credit(app, simple_user):
+    app = login(app, username='user', password='user')
+
+    regie = Regie.objects.create(label='Foo')
+    draft_invoice = DraftInvoice.objects.create(
+        regie=regie,
+        date_publication=datetime.date(2023, 4, 21),
+        date_payment_deadline=datetime.date(2023, 4, 22),
+        date_due=datetime.date(2023, 4, 23),
+        payer_external_id='payer:1',
+        payer_first_name='First',
+        payer_last_name='Last',
+        payer_address='41 rue des kangourous\n99999 Kangourou Ville',
+    )
+    DraftInvoiceLine.objects.create(
+        slug='event-a-foo-bar',
+        label='Event A',
+        event_date=datetime.date(2022, 9, 1),
+        invoice=draft_invoice,
+        quantity=-1,
+        unit_amount=1,
+        user_external_id='user:1',
+        user_first_name='First1',
+        user_last_name='Last1',
+    )
+    draft_invoice.refresh_from_db()
+    assert draft_invoice.total_amount == -1
+    basket = Basket.objects.create(
+        regie=regie,
+        draft_invoice=draft_invoice,
+        payer_nameid='ab' * 16,
+        expiry_at=now() + datetime.timedelta(hours=1),
+    )
+    line = BasketLine.objects.create(
+        basket=basket,
+        closed=True,
+        user_external_id='user:1',
+    )
+
+    resp = app.get('/basket/validate/')
+    with mock.patch('lingo.utils.requests_wrapper.RequestsSession.send') as mock_send:
+        resp = resp.form.submit()
+    assert {x[0][0].url for x in mock_send.call_args_list} == set()
+    basket.refresh_from_db()
+    assert basket.status == 'completed'
+    assert basket.validated_at is not None
+    assert basket.completed_at is not None
+    assert basket.invoice is None
+    credit = Credit.objects.latest('pk')
+    assert basket.credit == credit
+    assert credit.label == 'Credit from %s' % datetime.date.today().strftime('%d/%m/%Y')
+    assert credit.total_amount == 1
+    assert credit.regie == regie
+    assert credit.payer_external_id == 'payer:1'
+    assert credit.payer_first_name == 'First'
+    assert credit.payer_last_name == 'Last'
+    assert credit.payer_address == '41 rue des kangourous\n99999 Kangourou Ville'
+    assert credit.lines.count() == 1
+    (line1,) = credit.lines.all().order_by('pk')
+    assert line1.event_date == datetime.date(2022, 9, 1)
+    assert line1.slug == 'event-a-foo-bar'
+    assert line1.label == 'Event A'
+    assert line1.quantity == 1
+    assert line1.unit_amount == 1
+    assert line1.total_amount == 1
+    assert line1.user_external_id == 'user:1'
+    assert line1.user_first_name == 'First1'
+    assert line1.user_last_name == 'Last1'
+    assert Invoice.objects.count() == 0
+
+    # check callback
+    basket.status = 'open'
+    basket.save()
+    line.validation_callback_url = 'http://validation1.com'
+    line.credit_callback_url = 'http://credit1.com'
+    line.save()
+    BasketLine.objects.create(
+        basket=basket,
+        closed=True,
+        user_external_id='user:2',
+        validation_callback_url='http://validation2.com',
+        credit_callback_url='http://credit2.com',
+    )
+    resp = app.get('/basket/validate/')
+    with mock.patch('lingo.utils.requests_wrapper.RequestsSession.send') as mock_send:
+        resp = resp.form.submit()
+    basket.refresh_from_db()
+    credit = Credit.objects.latest('pk')
+    assert basket.credit == credit
+    assert Invoice.objects.count() == 0
+    assert {x[0][0].url for x in mock_send.call_args_list} == {
+        'http://validation1.com/',
+        'http://validation2.com/',
+        'http://credit1.com/',
+        'http://credit2.com/',
+    }
+
+
 def test_basket_cancel(app, simple_user):
     resp = app.get('/basket/cancel/')
     assert resp.location.endswith('/login/?next=/basket/cancel/')