Add renumber lectures button

app/controllers/admin/courses_controller.rb

@@ -1,5 +1,11 @@
 module Admin
   class CoursesController < Admin::ApplicationController
+    def renumber_lectures
+      course = Course.find(params[:id])
+      course.renumber_lectures!
+      redirect_to admin_course_url(course), notice: "Lectures renumbered!"
+    end
+
     # Overwrite any of the RESTful controller actions to implement custom behavior
     # For example, you may want to send an email after a foo is updated.
     #

app/views/admin/application/show.html.erb

@@ -67,6 +67,6 @@ as well as a link to its edit page.
   <% actions_template = "admin/#{page.resource.class.name.downcase}/actions" %>
 
   <% if lookup_context.template_exists?(actions_template, [], true) %>
-    <%= render actions_template %>
+    <%= render actions_template, { page: } %>
   <% end %>
 </section>

app/views/admin/course/_actions.html.erb

@@ -0,0 +1,5 @@
+<%= link_to(
+      "Renumber lectures",
+      [namespace, page.resource, :renumber_lectures],
+      class: "button",
+    ) if accessible_action?(page.resource, :renumber_lectures) %>

config/routes.rb

@@ -7,6 +7,8 @@ Rails.application.routes.draw do
     resources :recordings
 
     root to: "courses#index"
+
+    get '/courses/:id/renumber_lectures', to: 'courses#renumber_lectures', as: :course_renumber_lectures
   end
 
   root controller: :attendance_tracker, action: :index