Merge remote-tracking branch 'pleroma/develop' into feature/disable-account
[akkoma] / lib / pleroma / web / activity_pub / mrf / ensure_re_prepended.ex
index 06fafb3ee7b47f5f50aa4ee03e0bc4787b75b802..895376c9d68cd3ec9d0ecd6438300f642c11ca9b 100644 (file)
@@ -1,22 +1,29 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Pleroma.Web.ActivityPub.MRF.EnsureRePrepended do
   alias Pleroma.Object
 
   @behaviour Pleroma.Web.ActivityPub.MRF
 
+  @reply_prefix Regex.compile!("^re:[[:space:]]*", [:caseless])
   def filter_by_summary(
-        %{"summary" => parent_summary} = parent,
+        %{"summary" => parent_summary} = _parent,
         %{"summary" => child_summary} = child
       )
-      when not is_nil(child_summary) and child_summary == parent_summary and
-             byte_size(child_summary) > 1 do
-    if not String.starts_with?(child_summary, "re:") do
+      when not is_nil(child_summary) and byte_size(child_summary) > 0 and
+             not is_nil(parent_summary) and byte_size(parent_summary) > 0 do
+    if (child_summary == parent_summary and not Regex.match?(@reply_prefix, child_summary)) or
+         (Regex.match?(@reply_prefix, parent_summary) &&
+            Regex.replace(@reply_prefix, parent_summary, "") == child_summary) do
       Map.put(child, "summary", "re: " <> child_summary)
     else
       child
     end
   end
 
-  def filter_by_summary(parent, child), do: child
+  def filter_by_summary(_parent, child), do: child
 
   def filter(%{"type" => activity_type} = object) when activity_type == "Create" do
     child = object["object"]