feat(purchase/models.py): handle mock refunds

purchase/models.py

@@ -1,5 +1,6 @@
-from django.db import models
 from django.conf import settings
+from django.contrib.auth.models import Group
+from django.db import models
 
 
 class CoursePurchase(models.Model):
@@ -7,3 +8,16 @@ class CoursePurchase(models.Model):
     course = models.ForeignKey("home.CoursePage", on_delete=models.CASCADE)
     purchased_at = models.DateTimeField(auto_now_add=True)
     refunded = models.BooleanField(default=False)
+
+    def mock_refund(self):
+        self.refunded = True
+        self.save()
+
+    def save(self, *args, **kwargs):
+        super().save(*args, **kwargs)
+        group_name = f"course_{self.course.id}_access"
+
+        group, _ = Group.objects.get_or_create(name=group_name)
+        if self.refunded:
+            print(f"Removing user {self.user} from group {group_name} due to refund")
+            self.user.groups.remove(group)