Refactor sidebar component and combine secondary portions

This refactors the sidebar component to make it easier to determine
what is being rendered in each of the two sections and to render
it without accidentally duplicating the divider elements.

It also ensures that items that should be grouped together in the
second section are displayed in a single box, as noted in #1437.

Fixes #1437

app/components/also_available_component.html.erb

@@ -1,8 +1,6 @@
-<div class="mt-3 bg-fog-light component-container rounded">
-    <h2 class="h4">Also available at</h2>
-    <ul class="list-unstyled">
-        <% also_available_links.each do |label, url| %>
-            <li><%= link_to label, url %></li>
-        <% end %>
-    </ul>
-</div>
+<h2 class="h4">Also available at</h2>
+<ul class="list-unstyled">
+    <% also_available_links.each do |label, url| %>
+        <li><%= link_to label, url %></li>
+    <% end %>
+</ul>

app/components/document/sidebar_component.html.erb

@@ -1,17 +1,13 @@
-<% filtered_components = components.map{|component | render component }.uniq.compact_blank %>
-<% tools = render_show_tools %>
-<% if filtered_components.any? || tools.present?  %>
+<% filtered_components = filter_components(components) %>
+<% if filtered_components.any?  %>
   <div class="bg-fog-light component-container rounded">
-    <%= filtered_components.join('<hr style="border-top: dotted 1px;" />').html_safe if filtered_components.any? %>
-    <% if filtered_components.any? && tools.present? %>
-      <hr style="border-top: dotted 1px;" />
-    <% end %>
-    <%= tools %>
+    <%= safe_join filtered_components, separator %>
   </div>
 <% end %>
 
-<%= render AlsoAvailableComponent.new(document:) %>
-
-<div class="mt-4">
-  <%= render Blacklight::Document::MoreLikeThisComponent.new(document:) %>
-</div>
+<% filtered_components = filter_components(secondary_components) %>
+<% if filtered_components.any? %>
+  <div class="bg-fog-light component-container rounded mt-4">
+    <%= safe_join filtered_components, separator %>
+  </div>
+<% end %>

app/components/document/sidebar_component.rb

@@ -3,12 +3,33 @@
 # Render the sidebar on the show view
 module Document
   class SidebarComponent < Geoblacklight::Document::SidebarComponent
+    # Primary section of the sidebar that displays at the top
     def components
       [
         Geoblacklight::LoginLinkComponent.new(document:),
         Geoblacklight::StaticMapComponent.new(document:),
-        DownloadLinksComponent.new(document:)
+        DownloadLinksComponent.new(document:),
+        Blacklight::Document::ShowToolsComponent.new(document:)
       ]
     end
+
+    # Second section of the sidebar that displays below the main one
+    def secondary_components
+      [
+        AlsoAvailableComponent.new(document:),
+        'relations_container',
+        Blacklight::Document::MoreLikeThisComponent.new(document:)
+      ]
+    end
+
+    # Determine if there's actually anything to show by rendering everything
+    def filter_components(components)
+      components.map { |component| render component, document: }.compact_blank
+    end
+
+    # Rendered in between each component
+    def separator
+      content_tag :hr, nil, style: 'border-top: dotted 1px;'
+    end
   end
 end