Allow sponsorship payment terms(due date) to be changed

Allow the due date to be configured on an individual sponsorship level,
both specifying a number-of-days-to-pay and a hard final date.

Closes #170

docs/confreg/sponsors.md

@@ -341,6 +341,17 @@ Instant buy available
    administrator must manually move the sponsorship forward in the
    process once a signed contract is received.
 
+Number of days until payment is due
+:  The number of days until a sponsorship invoice is due. This defaults to 30
+   to give net 30 terms. The actual due date for an invoice might be restricted
+   by either *The Date the payment is due by* field.
+
+The Date the payment is due by
+:  The latest date that *Number of days until payment is due* applies until.
+   Invoices that would be due after this date are instead due at this time or
+   now(if this time is in the past).  This defaults to 5 days before the conference
+   starts.
+
 Payment methods for generated invoices
 :  Which payment methods will be listed on the generated
    invoices. Typically the instant buy levels support payment by

postgresqleu/confsponsor/backendforms.py

@@ -4,6 +4,7 @@
 from django.conf import settings
 
 from collections import OrderedDict
+import datetime
 import json
 
 from postgresqleu.util.db import exec_to_scalar
@@ -309,11 +310,12 @@ class BackendSponsorshipLevelForm(BackendForm):
     })
     allow_copy_previous = True
     auto_cascade_delete_to = ['sponsorshiplevel_paymentmethods', 'sponsorshipbenefit']
+    exclude_date_validators = ['paymentdueby', ]
 
     class Meta:
         model = SponsorshipLevel
         fields = ['levelname', 'urlname', 'levelcost', 'available', 'public', 'maxnumber', 'instantbuy',
-                  'paymentmethods', 'invoiceextradescription', 'contract', 'canbuyvoucher', 'canbuydiscountcode']
+                  'paymentdays', 'paymentdueby', 'paymentmethods', 'invoiceextradescription', 'contract', 'canbuyvoucher', 'canbuydiscountcode']
         widgets = {
             'paymentmethods': django.forms.CheckboxSelectMultiple,
         }
@@ -327,7 +329,7 @@ class Meta:
         {
             'id': 'contract',
             'legend': 'Contract information',
-            'fields': ['instantbuy', 'contract', ],
+            'fields': ['instantbuy', 'contract', 'paymentdays', 'paymentdueby'],
         },
         {
             'id': 'payment',
@@ -344,6 +346,8 @@ class Meta:
     def fix_fields(self):
         self.fields['contract'].queryset = SponsorshipContract.objects.filter(conference=self.conference)
         self.fields['paymentmethods'].label_from_instance = lambda x: "{0}{1}".format(x.internaldescription, x.active and " " or " (INACTIVE)")
+        if not self.initial.get('paymentdueby', None):
+            self.initial['paymentdueby'] = self.conference.startdate - datetime.timedelta(days=5)
 
     def clean(self):
         cleaned_data = super(BackendSponsorshipLevelForm, self).clean()

postgresqleu/confsponsor/invoicehandler.py

@@ -1,7 +1,6 @@
 from django.utils import timezone
 from django.conf import settings
-
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, time
 import base64
 import os
 
@@ -172,23 +171,19 @@ def create_sponsor_invoice(user, sponsor, override_duedate=None):
     level = sponsor.level
 
     invoicerows, reverse_vat = _invoicerows_for_sponsor(sponsor)
+    daystopay = timedelta(days=level.paymentdays)
 
     if override_duedate:
         duedate = override_duedate
-    elif conference.startdate < today_conference() + timedelta(days=5):
-        # If conference happens in the next 5 days, invoice is due immediately
+    elif level.paymentdueby < today_conference():
+        # The payment deadline has passed. Invoices are due immediately
         duedate = timezone.now()
-    elif conference.startdate < today_conference() + timedelta(days=30):
-        # Less than 30 days before the conference, set the due date to
-        # 5 days before the conference
-        duedate = timezone.make_aware(datetime.combine(
-            conference.startdate - timedelta(days=5),
-            timezone.now().time()
-        ))
+    elif level.paymentdueby < today_conference() + daystopay:
+        # The payment terms go beyond the payment deadline. The payment is due
+        # at the deadline
+        duedate = datetime.combine(level.paymentdueby, time(0, 0, 0, 0), conference.tzobj)
     else:
-        # More than 30 days before the conference, set the due date
-        # to 30 days from now.
-        duedate = timezone.now() + timedelta(days=30)
+        duedate = timezone.now() + daystopay
 
     manager = InvoiceManager()
     processor = invoicemodels.InvoiceProcessor.objects.get(processorname="confsponsor processor")

postgresqleu/confsponsor/migrations/0033_payment_terms.py

@@ -0,0 +1,35 @@
+# Generated by Django 3.2.22 on 2024-11-15 22:27
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('confsponsor', '0032_sponsorshipbenefit_include_in_data'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='sponsorshiplevel',
+            name='paymentdueby',
+            field=models.DateField(blank=True, help_text='The last acceptable due date for payments. If payment terms go beyond this date then the invoice is due at this date', null=True, verbose_name='The latest date the payment is due by'),
+        ),
+        migrations.RunSQL(
+            """
+            update confsponsor_sponsorshiplevel set paymentdueby=conf.startdate-'5 days'::interval from confreg_conference conf
+            where conf.id = conference_id
+            """,
+            ""
+        ),
+        migrations.AlterField(
+            model_name='sponsorshiplevel',
+            name='paymentdueby',
+            field=models.DateField(blank=False, help_text='The last acceptable due date for payments. If payment terms go beyond this date then the invoice is due at this date', null=False, verbose_name='The latest date the payment is due by'),
+        ),
+        migrations.AddField(
+            model_name='sponsorshiplevel',
+            name='paymentdays',
+            field=models.IntegerField(default=30, null=False, verbose_name='Number of days until payment is due'),
+        ),
+    ]

postgresqleu/confsponsor/models.py

@@ -56,6 +56,11 @@ class SponsorshipLevel(models.Model):
     contract = models.ForeignKey(SponsorshipContract, blank=True, null=True, on_delete=models.CASCADE)
     canbuyvoucher = models.BooleanField(null=False, blank=False, default=True, verbose_name="Can buy vouchers")
     canbuydiscountcode = models.BooleanField(null=False, blank=False, default=True, verbose_name="Can buy discount codes")
+    paymentdays = models.IntegerField(null=False, blank=False, default=30, verbose_name="Number of days until payment is due")
+    paymentdueby = models.DateField(
+        null=False, blank=False, verbose_name="The latest date the payment is due by",
+        help_text="The last acceptable due date for payments. If payment terms go beyond this date then the invoice is due at this date",
+    )
 
     def __str__(self):
         return self.levelname