Add supplements to admin section

app/admin/supplement.rb

@@ -0,0 +1,43 @@
+ActiveAdmin.register Supplement do
+  decorate_with SupplementDecorator
+  config.filters = false
+
+  index download_links: false do
+    column :title
+    column :pages
+    default_actions
+  end
+
+  form partial: 'form'
+
+  show title: :title do |supplement|
+    attributes_table do
+      row :number
+      row :title
+      row :author_names
+      row :pages
+      row :description
+      row(Supplement.human_attribute_name(:pdf)) { supplement.pdf_download_link }
+    end
+  end
+
+  controller do
+    def authors
+      Author.all.decorate.map { |author| [author.full_name, author.id] }
+    end
+
+    def current_author_ids
+      @supplement.authors.pluck(:id)
+    end
+
+    def form_action
+      @supplement.persisted? ? [:admin, @supplement] : [:admin, :supplements]
+    end
+
+    helper_method :volumes, :authors, :current_volume_id, :current_author_ids, :keyword_names, :keywords, :form_action
+
+    def permitted_params
+      params.permit({ supplement: [{ author_ids: [] }, :number, :title, :pages, :description, :pdf, :id] })
+    end
+  end
+end

app/decorators/supplement_decorator.rb

@@ -1,8 +1,12 @@
 class SupplementDecorator < ApplicationDecorator
-  delegate :number, :title, :pages, :pdf, :pdf_file_name
+  delegate :number, :title, :pages, :description, :pdf, :pdf_file_name
   decorates_associations :authors
 
   def author_names
     authors.map { |author| "<span class=nowrap>#{author.full_name}</span>" }.join(', ').html_safe
   end
+
+  def pdf_download_link
+    h.link_to('Download', pdf.url) if pdf_file_name
+  end
 end

app/views/admin/supplements/_form.html.haml

@@ -0,0 +1,10 @@
+= semantic_form_for(@supplement, url: form_action) do |f|
+  = f.inputs do
+    = f.input :number
+    = f.input :title, as: :text, input_html: { rows: 3 }
+    = f.input :authors, collection: authors, selected: current_author_ids, required: false, input_html: { class: :select2, multiple: true }
+    = f.input :pages
+    = f.input :description
+    = f.input :pdf, label: 'PDF', required: false
+
+  = f.actions

spec/features/admin_supplements_spec.rb

@@ -0,0 +1,33 @@
+require 'spec_helper'
+
+feature 'visiting the supplements admin section' do
+  scenario 'the user sees a list of supplements' do
+    supplement = FactoryGirl.create(:supplement)
+    log_in_admin_user
+    visit admin_supplements_path
+
+    expect(page).to have_css('tr', text: supplement.title)
+  end
+end
+
+feature 'adding a new supplement', :js do
+  scenario 'the user adds a new supplement and is redirected to the show page' do
+    author = FactoryGirl.create(:author).decorate
+    supplement = FactoryGirl.build_stubbed(:supplement)
+
+    log_in_admin_user
+    visit new_admin_supplement_path
+
+    fill_in 'Number', with: supplement.number
+    fill_in 'Title', with: supplement.title
+    select2 author.full_name, from: 'Authors'
+    fill_in 'Pages', with: supplement.pages
+    fill_in 'Description', with: supplement.description
+    attach_file 'PDF', File.join(Rails.root, 'spec', 'support', 'test.pdf')
+    click_on 'Create Supplement'
+
+    expect(current_path).to eql(admin_supplement_path(Supplement.last))
+    expect(page).to have_content('Supplement was successfully created')
+    expect(Supplement.count).to eql(1)
+  end
+end