Search: Better sorting for user searches.

lib/pleroma/user/search.ex

@@ -4,6 +4,7 @@
 
 defmodule Pleroma.User.Search do
   alias Pleroma.EctoType.ActivityPub.ObjectValidators.Uri, as: UriType
+  alias Pleroma.Instances.Instance
   alias Pleroma.Pagination
   alias Pleroma.User
 
@@ -88,12 +89,13 @@ defmodule Pleroma.User.Search do
     |> filter_invisible_users()
     |> filter_internal_users()
     |> filter_blocked_domains(for_user)
+    |> filter_unreachable_users()
     |> fts_search(query_string)
     |> select_top_users(top_user_ids)
     |> trigram_rank(query_string)
     |> boost_search_rank(for_user, top_user_ids)
     |> subquery()
-    |> order_by(desc: :search_rank)
+    |> order_by_search_rank(for_user)
     |> maybe_restrict_local(for_user)
     |> maybe_restrict_accepting_chat_messages(capabilities)
     |> filter_deactivated_users()
@@ -196,6 +198,14 @@ defmodule Pleroma.User.Search do
 
   defp filter_blocked_domains(query, _), do: query
 
+  defp filter_unreachable_users(query) do
+    from(u in query,
+      left_join: i in Instance,
+      on: i.host == fragment("substring(? from '.*://([^/]*)')", u.ap_id),
+      where: is_nil(i.unreachable_since)
+    )
+  end
+
   defp maybe_resolve(true, user, query) do
     case {limit(), user} do
       {:all, _} -> :noop
@@ -236,6 +246,16 @@ defmodule Pleroma.User.Search do
 
     from(u in subquery(query),
       select_merge: %{
+        search_type:
+          fragment(
+            """
+            CASE WHEN (?) THEN 2
+            WHEN (?) THEN 1
+            ELSE 0 END
+            """,
+            u.id in ^top_user_ids,
+            u.id in ^friends_ids or u.id in ^followers_ids
+          ),
         search_rank:
           fragment(
             """
@@ -261,6 +281,14 @@ defmodule Pleroma.User.Search do
   defp boost_search_rank(query, _for_user, top_user_ids) do
     from(u in subquery(query),
       select_merge: %{
+        search_type:
+          fragment(
+            """
+            CASE WHEN (?) THEN 2
+            ELSE 0 END
+            """,
+            u.id in ^top_user_ids
+          ),
         search_rank:
           fragment(
             """
@@ -273,4 +301,22 @@ defmodule Pleroma.User.Search do
       }
     )
   end
+
+  defp order_by_search_rank(query, %User{}) do
+    order_by(
+      query,
+      [u],
+      desc: u.search_type,
+      desc_nulls_last:
+        fragment(
+          "CASE WHEN ? = 1 THEN COALESCE(?, ?) ELSE NULL END",
+          u.search_type,
+          u.last_status_at,
+          u.last_active_at
+        ),
+      desc: u.search_rank
+    )
+  end
+
+  defp order_by_search_rank(query, _), do: order_by(query, desc: :search_rank)
 end