From 08d60ce6672ef502231bd3ef04e0ee8e3a59db47 Mon Sep 17 00:00:00 2001
From: Ariadne Conill <ariadne@dereferenced.org>
Date: Sun, 25 Aug 2019 23:23:53 +0000
Subject: [PATCH] activitypub: remove thread_visibility() SQL function calls

---
 lib/pleroma/web/activity_pub/activity_pub.ex | 24 ------------------------
 lib/pleroma/web/activity_pub/visibility.ex   | 22 ++++++++++++++--------
 2 files changed, 14 insertions(+), 32 deletions(-)

diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index 172c952d4..ab29ee497 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -604,25 +604,6 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
 
   defp restrict_visibility(query, _visibility), do: query
 
-  defp restrict_thread_visibility(query, _, %{skip_thread_containment: true} = _),
-    do: query
-
-  defp restrict_thread_visibility(
-         query,
-         %{"user" => %User{info: %{skip_thread_containment: true}}},
-         _
-       ),
-       do: query
-
-  defp restrict_thread_visibility(query, %{"user" => %User{ap_id: ap_id}}, _) do
-    from(
-      a in query,
-      where: fragment("thread_visibility(?, (?)->>'id') = true", ^ap_id, a.data)
-    )
-  end
-
-  defp restrict_thread_visibility(query, _, _), do: query
-
   def fetch_user_activities(user, reading_user, params \\ %{}) do
     params =
       params
@@ -921,10 +902,6 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
   defp maybe_order(query, _), do: query
 
   def fetch_activities_query(recipients, opts \\ %{}) do
-    config = %{
-      skip_thread_containment: Config.get([:instance, :skip_thread_containment])
-    }
-
     Activity
     |> maybe_preload_objects(opts)
     |> maybe_preload_bookmarks(opts)
@@ -944,7 +921,6 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
     |> restrict_muted(opts)
     |> restrict_media(opts)
     |> restrict_visibility(opts)
-    |> restrict_thread_visibility(opts, config)
     |> restrict_replies(opts)
     |> restrict_reblogs(opts)
     |> restrict_pinned(opts)
diff --git a/lib/pleroma/web/activity_pub/visibility.ex b/lib/pleroma/web/activity_pub/visibility.ex
index dfb166b65..398c65d97 100644
--- a/lib/pleroma/web/activity_pub/visibility.ex
+++ b/lib/pleroma/web/activity_pub/visibility.ex
@@ -5,7 +5,6 @@
 defmodule Pleroma.Web.ActivityPub.Visibility do
   alias Pleroma.Activity
   alias Pleroma.Object
-  alias Pleroma.Repo
   alias Pleroma.User
 
   require Pleroma.Constants
@@ -58,14 +57,21 @@ defmodule Pleroma.Web.ActivityPub.Visibility do
     visible_for_user?(activity, nil) || Enum.any?(x, &(&1 in y))
   end
 
-  def entire_thread_visible_for_user?(%Activity{} = activity, %User{} = user) do
-    {:ok, %{rows: [[result]]}} =
-      Ecto.Adapters.SQL.query(Repo, "SELECT thread_visibility($1, $2)", [
-        user.ap_id,
-        activity.data["id"]
-      ])
+  # XXX: Probably even more inefficient than the previous implementation intended to be a placeholder untill https://git.pleroma.social/pleroma/pleroma/merge_requests/971 is in develop
+  # credo:disable-for-previous-line Credo.Check.Readability.MaxLineLength
+  def entire_thread_visible_for_user?(
+        %Activity{} = tail,
+        # %Activity{data: %{"object" => %{"inReplyTo" => parent_id}}} = tail,
+        user
+      ) do
+    case Object.normalize(tail) do
+      %{data: %{"inReplyTo" => parent_id}} when is_binary(parent_id) ->
+        parent = Activity.get_in_reply_to_activity(tail)
+        visible_for_user?(tail, user) && entire_thread_visible_for_user?(parent, user)
 
-    result
+      _ ->
+        visible_for_user?(tail, user)
+    end
   end
 
   def get_visibility(object) do