activitypub: visibility: use SQL thread_visibility() function instead of manually walking the thread

lib/pleroma/web/activity_pub/visibility.ex

@@ -1,6 +1,7 @@
 defmodule Pleroma.Web.ActivityPub.Visibility do
   alias Pleroma.Activity
   alias Pleroma.Object
+  alias Pleroma.Repo
   alias Pleroma.User
 
   def is_public?(%Object{data: %{"type" => "Tombstone"}}), do: false
@@ -38,25 +39,14 @@ def visible_for_user?(activity, user) do
     visible_for_user?(activity, nil) || Enum.any?(x, &(&1 in y))
   end
 
-  # guard
+  def entire_thread_visible_for_user?(%Activity{} = activity, %User{} = user) do
-  def entire_thread_visible_for_user?(nil, _user), do: false
+    {: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
+    result
-  # 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)
-
-      _ ->
-        visible_for_user?(tail, user)
-    end
   end
 
   def get_visibility(object) do