Update day discound calc

apps/payment/models.py

@@ -144,7 +144,10 @@ class SchoolPayment(Payment):
         verbose_name_plural = 'Платежи за школу'
 
     def __str__(self):
-        days = ', '.join([dict(SchoolSchedule.WEEKDAY_CHOICES).get(weekday, '') for weekday in sorted(self.weekdays)])
+        days = ', '.join([
+            dict(SchoolSchedule.WEEKDAY_CHOICES).get(weekday, '')
+            for weekday in sorted(self.weekdays)
+        ])
         return days
 
     def save(self, *args, **kwargs):
@@ -152,9 +155,11 @@ class SchoolPayment(Payment):
             weekday__in=self.weekdays,
         ).aggregate(
             models.Sum('month_price'),
-            models.Sum('day_discount'),
         )
         month_price_sum = aggregate.get('month_price__sum', 0)
-        day_discount_sum = aggregate.get('day_discount__sum', 0) if len(self.weekdays) == 7 else 0
-        self.amount = month_price_sum - day_discount_sum
+        if month_price_sum >= config.SERVICE_DISCOUNT_MIN_AMOUNT:
+            discount = config.SERVICE_DISCOUNT
+        else:
+            discount = 0
+        self.amount = month_price_sum - discount
         super().save(*args, **kwargs)

project/settings.py

@@ -234,6 +234,7 @@ CONSTANCE_CONFIG = OrderedDict((
     ('INSTAGRAM_RESULTS_TAG', ('#lil_акварель', 'Тэг результатов работ.')),
     ('INSTAGRAM_RESULTS_PATH', ('media/instagram/results/', 'Путь до результатов работ.')),
     ('SERVICE_COMMISSION', (10, 'Комиссия сервиса в процентах.')),
+    ('SERVICE_DISCOUNT_MIN_AMOUNT', (3500, 'Минимальная сумма платежа для школы, после которой вычитывается скидка SERVICE_DISCOUNT.')),
     ('SERVICE_DISCOUNT', (1000, 'Комиссия сервиса при покупке всех дней.')),
 ))