From 41f42e33ed3d271b575866c805242855fcf9dc39 Mon Sep 17 00:00:00 2001
From: Mouse Reeve <mousereeve@riseup.net>
Date: Tue, 5 Jul 2022 13:28:09 -0700
Subject: [PATCH] Moves list add notification into notification model

Right now notifications are a mix of post-save signals and clauses in
the save function of the model. I'm not actually sure which is better,
but I'm moving them to signals where it's straightforward to be
consistent.
---
 bookwyrm/models/list.py         | 22 ----------------------
 bookwyrm/models/notification.py | 32 +++++++++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 23 deletions(-)

diff --git a/bookwyrm/models/list.py b/bookwyrm/models/list.py
index db4dc5806..f280f1e28 100644
--- a/bookwyrm/models/list.py
+++ b/bookwyrm/models/list.py
@@ -1,7 +1,6 @@
 """ make a list of books!! """
 import uuid
 
-from django.apps import apps
 from django.core.exceptions import PermissionDenied
 from django.db import models
 from django.db.models import Q
@@ -152,32 +151,11 @@ class ListItem(CollectionItemMixin, BookWyrmModel):
 
     def save(self, *args, **kwargs):
         """create a notification too"""
-        created = not bool(self.id)
         super().save(*args, **kwargs)
         # tick the updated date on the parent list
         self.book_list.updated_date = timezone.now()
         self.book_list.save(broadcast=False, update_fields=["updated_date"])
 
-        list_owner = self.book_list.user
-        model = apps.get_model("bookwyrm.Notification", require_ready=True)
-        # create a notification if somoene ELSE added to a local user's list
-        if created and list_owner.local and list_owner != self.user:
-            model.objects.create(
-                user=list_owner,
-                related_user=self.user,
-                related_list_item=self,
-                notification_type=model.ADD,
-            )
-
-        if self.book_list.group:
-            for membership in self.book_list.group.memberships.all():
-                if membership.user != self.user:
-                    model.objects.create(
-                        user=membership.user,
-                        related_user=self.user,
-                        related_list_item=self,
-                        notification_type=model.ADD,
-                    )
 
     def raise_not_deletable(self, viewer):
         """the associated user OR the list owner can delete"""
diff --git a/bookwyrm/models/notification.py b/bookwyrm/models/notification.py
index 53fea7157..726dc1beb 100644
--- a/bookwyrm/models/notification.py
+++ b/bookwyrm/models/notification.py
@@ -2,7 +2,8 @@
 from django.db import models, transaction
 from django.dispatch import receiver
 from .base_model import BookWyrmModel
-from . import Boost, Favorite, GroupMemberInvitation, ImportJob, Report, Status, User
+from . import Boost, Favorite, GroupMemberInvitation, ImportJob, ListItem, Report
+from . import Status, User
 
 
 class Notification(BookWyrmModel):
@@ -219,3 +220,32 @@ def notify_user_on_group_invite(sender, instance, *args, **kwargs):
         related_group=instance.group,
         notification_type=Notification.INVITE,
     )
+
+
+@receiver(models.signals.post_save, sender=ListItem)
+@transaction.atomic
+# pylint: disable=unused-argument
+def notify_user_on_list_item_add(sender, instance, created, *args, **kwargs):
+    """Someone added to your list"""
+    if not created:
+        return
+
+    list_owner = instance.book_list.user
+    # create a notification if somoene ELSE added to a local user's list
+    if list_owner.local and list_owner != instance.user:
+        Notification.notify(
+            list_owner,
+            instance.user,
+            related_list_item=instance,
+            notification_type=Notification.ADD
+        )
+
+    if instance.book_list.group:
+        for membership in instance.book_list.group.memberships.all():
+            if membership.user != instance.user:
+                Notification.notify(
+                    membership.user,
+                    instance.user,
+                    related_list_item=instance,
+                    notification_type=Notification.ADD,
+                )