add subfolders

app/controllers/template_folders_autocomplete_controller.rb

@@ -3,14 +3,31 @@
 class TemplateFoldersAutocompleteController < ApplicationController
   load_and_authorize_resource :template_folder, parent: false
 
-  LIMIT = 100
+  LIMIT = 30
 
   def index
-    templates_query = Template.accessible_by(current_ability).where(archived_at: nil)
+    parent_name, name =
+      if params[:parent_name].present?
+        [params[:parent_name], params[:q]]
+      else
+        params[:q].to_s.split(' /', 2).map(&:squish)
+      end
 
-    template_folders = @template_folders.where(id: templates_query.select(:folder_id))
-    template_folders = TemplateFolders.search(template_folders, params[:q]).limit(LIMIT)
+    if name
+      parent_folder = @template_folders.find_by(name: parent_name, parent_folder_id: nil)
+    else
+      name = parent_name
+    end
 
-    render json: template_folders.as_json(only: %i[name archived_at])
+    template_folders = TemplateFolders.filter_active_folders(@template_folders.where(parent_folder:),
+                                                             Template.accessible_by(current_ability))
+
+    name = name.to_s.downcase
+
+    template_folders = TemplateFolders.search(template_folders, name).order(id: :desc).limit(LIMIT)
+
+    render json: template_folders.preload(:parent_folder)
+                                 .sort_by { |e| e.name.downcase.index(name) || Float::MAX }
+                                 .as_json(only: %i[name archived_at], methods: %i[full_name])
   end
 end