Fix updating of snapshot values

nummi/main/forms.py

@@ -71,15 +71,5 @@ class SnapshotForm(NummiForm):
             id__in=self.cleaned_data["transactions"]
         )
 
-        to_update = list(
-            new_transactions.order_by().only("snapshot").distinct("snapshot")
-        )
-
-        instance.account.transaction_set.add(*new_transactions)
-        instance.transaction_set.add(*new_transactions)
-        instance.update_sum()
-
-        for upd in to_update:
-            upd.snapshot.update_sum()
-
+        instance.transaction_set.add(*new_transactions, bulk=False)
         return instance

nummi/main/models.py

@@ -159,10 +159,15 @@ class Snapshot(AccountModel):
                 trans.save()
 
         self.diff = self.value - self.start_value
+        self.sum = (
+            self.transaction_set.aggregate(sum=models.Sum("value")).get("sum", 0) or 0
+        )
         super().save(*args, **kwargs)
 
     def update_sum(self):
-        self.sum = self.transaction_set.aggregate(sum=models.Sum("value")).get("sum", 0)
+        self.sum = (
+            self.transaction_set.aggregate(sum=models.Sum("value")).get("sum", 0) or 0
+        )
         super().save()
 
     def delete(self, *args, **kwargs):
@@ -219,9 +224,13 @@ class Transaction(CustomModel):
     )
 
     def save(self, *args, **kwargs):
+        if Transaction.objects.filter(pk=self.pk):
             prev_self = Transaction.objects.get(pk=self.pk)
+        else:
+            prev_self = None
         self.account = self.snapshot.account
         super().save(*args, **kwargs)
+        if prev_self is not None:
             prev_self.snapshot.update_sum()
         self.snapshot.update_sum()
 

nummi/main/templates/main/snapshot_form.html

@@ -71,9 +71,9 @@
                 {% endfor %}
             </div>
         {% endif %}
-        {% if snapshot.transactions %}
+        {% if snapshot.transaction_set.all %}
             <h2>{% translate "Transactions" %} ({{ snapshot.sum|pmvalue }} / {{ snapshot.diff|pmvalue }})</h2>
-            {% transaction_table snapshot.transactions %}
+            {% transaction_table snapshot.transaction_set.all %}
         {% endif %}
     {% endwith %}
 {% endblock %}