notebook/app/views/content/display/sidebar/_references.html.erb

<%
  creating = defined?(creating) && creating
  editing  = defined?(editing)  && editing
%>

<%
  raw_model = content.is_a?(ContentSerializer) ? content.raw_model : content
%>

<% related_documents = content.documents.select { |doc| (current_user || User.new).can_read?(doc) } %>

<%
  show_in_this_universe_tab = !creating && !editing && raw_model.is_a?(Universe)
  show_associations_tab     = !creating && !editing && @sidelinks_association_count > 0
  show_gallery_tab          = creating || editing || raw_model.image_uploads.any?
  show_documents_tab        = !creating && !editing && related_documents.any?
  show_shares_tab           = !creating && !editing && raw_model.content_page_shares.any?
  show_collections_tab      = !creating && !editing && raw_model.page_collection_submissions.accepted.any?
  show_timelines_tab        = !creating && !editing && raw_model.timelines.any? && user_signed_in? && current_user == raw_model.user

  show_references_section = [
    show_in_this_universe_tab, 
    show_associations_tab, 
    show_gallery_tab, 
    show_documents_tab, 
    show_shares_tab, 
    show_collections_tab,
    show_timelines_tab
  ].any?
%>

<% if show_references_section %>
  <ul class="collection content-tabs">
    <li class="active center grey-text uppercase">
      References
    </li>

    <% if show_in_this_universe_tab %>
      <li class="collection-item tab">
        <a href="#in_this_universe_panel">
          <i class="material-icons left"><%= Universe.icon %></i>
          In this universe
          <span class="badge hide-on-med-and-down"><%= @sidelinks_in_this_universe_count %></span>
        </a>
      </li>
    <% end %>

    <% if show_associations_tab %>
      <li class="collection-item tab">
        <a href="#associations_panel">
          <i class="material-icons left">link</i>
          Associations
          <span class="badge hide-on-med-and-down"><%= @sidelinks_association_count %></span>
        </a>
      </li>
    <% end %>

    <% if show_gallery_tab %>
      <li class="collection-item tab">
        <a href="#gallery_panel">
          <i class="material-icons left">photo_library</i>
          Gallery
          <span class="badge hide-on-med-and-down"><%= raw_model.image_uploads.count %></span>
        </a>
      </li>
    <% end %>

    <% if show_timelines_tab %>
      <li class="collection-item tab">
        <a href="#timelines_panel">
          <i class="material-icons left"><%= Timeline.icon %></i>
          Timelines
          <span class="badge hide-on-med-and-down"><%= raw_model.timelines.count %></span>
        </a>
      </li>
    <% end %>

    <% if show_documents_tab %>
      <li class="collection-item tab">
        <a href="#documents_panel">
          <i class="material-icons left"><%= Document.icon %></i>
          Documents
          <span class="badge hide-on-med-and-down"><%= related_documents.count %></span>
        </a>
      </li>
    <% end %>

    <% if show_shares_tab %>
      <li class="collection-item tab">
        <a href="#shares_panel">
          <i class="material-icons left"><%= ContentPageShare.icon %></i>
          Shares
          <span class="badge hide-on-med-and-down"><%= raw_model.content_page_shares.count %></span>
        </a>
      </li>
    <% end %>

    <% if show_collections_tab %>
      <li class="collection-item tab">
        <a href="#collections_panel">
          <i class="material-icons left"><%= PageCollection.icon %></i>
          Collections
          <span class="badge hide-on-med-and-down"><%= raw_model.page_collection_submissions.accepted.count %></span>
        </a>
      </li>
    <% end %>
  </ul>
<% end %>