30 files changed, 388 insertions, 125 deletions

diff --git a/app/controllers/assets_controller.rb b/app/controllers/assets_controller.rb
index d150e06..becfe13 100644
--- a/app/controllers/assets_controller.rb
+++ b/app/controllers/assets_controller.rb
@@ -89,6 +89,6 @@ class AssetsController < ApplicationController
   private
 
     def asset_params
-      params.require(:asset).permit(:name, :upload)
+      params.require(:asset).permit(:name, :upload, :creator, :source_url, :license_key)
     end
 end
diff --git a/app/controllers/pages_controller.rb b/app/controllers/pages_controller.rb
index 2d08dea..326fbd4 100644
--- a/app/controllers/pages_controller.rb
+++ b/app/controllers/pages_controller.rb
@@ -6,6 +6,19 @@ class PagesController < ApplicationController
 
   def preview
     @page = Page.find(params[:id])
+    unless @page.node
+      node = Node.find_by(autosave_id: @page.id) ||
+             Node.find_by(draft_id: @page.id) ||
+             Node.find_by(head_id: @page.id)
+      @page.node = node if node
+    end
+
+    node ||= @page.node
+    if node && node.draft_id == @page.id && node.autosave
+      @page = node.autosave
+      @page.node = node
+    end
+
 
     if @page
       template = @page.valid_template
@@ -15,11 +28,4 @@ class PagesController < ApplicationController
       )
     end
   end
-
-  def sort_images
-    page = Page.find(params[:id])
-    page.update_assets(params[:images])
-    
-    head :ok
-  end
 end
diff --git a/app/controllers/related_assets_controller.rb b/app/controllers/related_assets_controller.rb
index 5af73fc..ca894f2 100644
--- a/app/controllers/related_assets_controller.rb
+++ b/app/controllers/related_assets_controller.rb
@@ -5,10 +5,10 @@ class RelatedAssetsController < ApplicationController
   def search
     term = params[:search_term].to_s.strip
     attached_ids = @node.editable_page.related_assets.pluck(:asset_id)
-    scope = Asset.images.where.not(id: attached_ids)
+    scope = Asset.headline_eligible.where.not(id: attached_ids)
 
     results = if term.present?
-      scope.where("name ILIKE ?", "%#{term}%").limit(10)
+      scope.where("name ILIKE :term OR upload_file_name ILIKE :term", term: "%#{term}%").limit(10)
     else
       scope.order(created_at: :desc).limit(5)
     end
@@ -26,6 +26,7 @@ class RelatedAssetsController < ApplicationController
       id: related.id,
       asset_id: asset.id,
       name: asset.name,
+      has_credit: asset.show_credit?,
       thumb_url: asset.upload.url(:thumb),
       large_url: asset.upload.url(:large),
       original_url: asset.upload.url,
@@ -39,7 +40,17 @@ class RelatedAssetsController < ApplicationController
   end
 
   def update
-    @node.editable_page.related_assets.find(params[:id]).insert_at(params[:position].to_i)
+    related = @node.editable_page.related_assets.find(params[:id])
+
+    if params.key?(:headline)
+      RelatedAsset.transaction do
+        @node.editable_page.related_assets.update_all(headline: false)
+        related.update!(headline: true) if params[:headline] == "true"
+      end
+    else
+      related.insert_at(params[:position].to_i)
+    end
+
     head :ok
   end
 
diff --git a/app/controllers/shared_previews_controller.rb b/app/controllers/shared_previews_controller.rb
index f6fb45a..65f744d 100644
--- a/app/controllers/shared_previews_controller.rb
+++ b/app/controllers/shared_previews_controller.rb
@@ -8,7 +8,7 @@ class SharedPreviewsController < ApplicationController
       is_draft = node.draft_id == @page.id
 
       currently_public = is_head && @page.public?
-      superseded        = !is_head && !is_draft
+      superseded       = !is_head && !is_draft
 
       if superseded || currently_public
         redirect_to @page.public_link
diff --git a/app/helpers/content_helper.rb b/app/helpers/content_helper.rb
index 5810966..7a52d9c 100644
--- a/app/helpers/content_helper.rb
+++ b/app/helpers/content_helper.rb
@@ -53,11 +53,8 @@ module ContentHelper
   end
 
   def headline_image
-    @images = @page.assets.images
-
-    unless @images.empty?
-      render :partial => 'content/headline_image'
-    end
+    @headline_asset = @page.headline_asset
+    render :partial => 'content/headline_image' if @headline_asset || @page.assets.images.any? || @page.assets.pdfs.any?
   end
 
   # Returns the published_at attribute of a page if it is not nil, otherwise
@@ -154,4 +151,30 @@ module ContentHelper
     )
   end
 
+  def asset_credit(asset)
+    return nil unless asset
+    return nil unless asset.has_credit?
+
+    license = AssetLicense.find(asset.license_key)
+
+    photo_label = t("asset_credits.photo", name: asset.name)
+    photo = asset.source_url.present? ? link_to(photo_label, asset.source_url) : photo_label
+
+    attribution_parts = [photo]
+    attribution_parts << t("asset_credits.by", creator: asset.creator) if asset.creator.present?
+    attribution = safe_join(attribution_parts, " ")
+
+    license_text = if license
+      name = t("asset_licenses.#{license.key}", default: license.key)
+      phrase = license.style == "license" ? t("asset_credits.licensed_under", license: name) : name
+      license.url.present? ? link_to(phrase, license.url) : phrase
+    end
+
+    full = license_text ? safe_join([attribution, license_text], ", ") : attribution
+    safe_join([full, "."])
+  end
+
+  def glightbox_data(image, title)
+    "title: #{title.to_s.tr(';', ',')};"
+  end
 end
diff --git a/app/models/asset.rb b/app/models/asset.rb
index aca0ee8..ba9c2f0 100644
--- a/app/models/asset.rb
+++ b/app/models/asset.rb
@@ -1,12 +1,34 @@
 class Asset < ApplicationRecord
+  IMAGE_CONTENT_TYPES = ["image/gif", "image/jpeg", "image/png", "image/webp"]
+  PDF_CONTENT_TYPE = "application/pdf"
 
   include FileAttachment
   
   has_many :related_assets, :dependent => :destroy
   has_many :pages, :through => :related_assets
 
-  scope :images,    -> { where(:upload_content_type => ["image/gif", "image/jpeg", "image/png", "image/webp"]) }
+  scope :images,    -> { where(:upload_content_type => IMAGE_CONTENT_TYPES) }
   scope :documents, -> { where(:upload_content_type => ["application/pdf", "text/plain", "text/rtf"]) }
   scope :audio,     -> { where(:upload_content_type => ["audio/mpeg", "audio/x-m4a", "audio/wav", "audio/x-wav"]) }
+  scope :pdfs,      -> { where(:upload_content_type => PDF_CONTENT_TYPE) }
 
+  scope :headline_eligible, -> { where(:upload_content_type => IMAGE_CONTENT_TYPES + [PDF_CONTENT_TYPE]) }
+
+  validates :license_key, inclusion: { in: -> { AssetLicense.keys } }, allow_blank: true
+
+  def image?
+    IMAGE_CONTENT_TYPES.include?(upload_content_type)
+  end
+
+  def pdf?
+    upload_content_type == PDF_CONTENT_TYPE
+  end
+
+  def has_credit?
+    creator.present? || source_url.present? || license_key.present?
+  end
+
+  def show_credit?
+    image? && has_credit?
+  end
 end
diff --git a/app/models/asset_license.rb b/app/models/asset_license.rb
new file mode 100644
index 0000000..ca66d40
--- /dev/null
+++ b/app/models/asset_license.rb
@@ -0,0 +1,15 @@
+class AssetLicense
+  Entry = Struct.new(:key, :url, :requires_attribution, :style, keyword_init: true)
+
+  DICTIONARY = YAML.load_file(Rails.root.join("config", "asset_licenses.yml")).freeze
+
+  def self.keys
+    DICTIONARY.keys
+  end
+
+  def self.find(key)
+    entry = DICTIONARY[key.to_s] if key.present?
+    return nil unless entry
+    Entry.new(key: key.to_s, url: entry["url"], requires_attribution: entry["requires_attribution"], style: entry["style"])
+  end
+end
diff --git a/app/models/concerns/file_attachment.rb b/app/models/concerns/file_attachment.rb
index 613a6f0..6221312 100644
--- a/app/models/concerns/file_attachment.rb
+++ b/app/models/concerns/file_attachment.rb
@@ -31,6 +31,7 @@ module FileAttachment
 
   IMAGE_CONTENT_TYPES    = %w[image/jpeg image/gif image/png image/webp].freeze
   VECTOR_CONTENT_TYPES   = %w[image/svg+xml].freeze
+  RASTERIZED_CONTENT_TYPES = %w[application/pdf].freeze
   DISPLAYABLE_AS_IMAGE   = IMAGE_CONTENT_TYPES + VECTOR_CONTENT_TYPES
 
   included do
@@ -52,29 +53,49 @@ module FileAttachment
     build_upload_proxy
   end
 
+  def has_variant?(style)
+    upload_file_name.present? && File.exist?(file_path(style))
+  end
+
+  def previewable?
+    has_variant?(:medium)
+  end
+
+  def variant_filename(style)
+    return upload_file_name if style == :original || !RASTERIZED_CONTENT_TYPES.include?(upload_content_type)
+    File.basename(upload_file_name, ".*") + ".png"
+  end
+
   private
 
   def build_upload_proxy
     @upload = UploadProxy.new(self)
   end
 
+  class_methods do
+    def upload_root
+      Rails.env.test? ? Rails.root.join("tmp", "test_uploads") : Rails.root.join("public", "system", "uploads")
+    end
+  end
+
+  def upload_root
+    self.class.upload_root
+  end
+
   def process_upload
     return unless @pending_upload
     uploaded_file = @pending_upload
     @pending_upload = nil
 
-    old_dir = Rails.root.join("public", "system", "uploads", id.to_s)
+    old_dir = upload_root.join(id.to_s)
+
     FileUtils.rm_rf(old_dir) if Dir.exist?(old_dir)
 
     original_path = file_path(:original)
     FileUtils.mkdir_p(File.dirname(original_path))
     FileUtils.cp(uploaded_file.tempfile.path, original_path)
 
-    if IMAGE_CONTENT_TYPES.include?(upload_content_type)
-      generate_variants(original_path)
-    elsif VECTOR_CONTENT_TYPES.include?(upload_content_type)
-      generate_svg_variants(original_path)
-    end
+    generate_all_variants(original_path)
   end
 
   def generate_variants(original_path)
@@ -93,20 +114,28 @@ module FileAttachment
     end
   end
 
+  def generate_all_variants(original_path)
+    if IMAGE_CONTENT_TYPES.include?(upload_content_type)
+      generate_variants(original_path)
+    elsif VECTOR_CONTENT_TYPES.include?(upload_content_type)
+      generate_svg_variants(original_path)
+    elsif RASTERIZED_CONTENT_TYPES.include?(upload_content_type)
+      generate_variants("#{original_path}[0]")
+    end
+  end
+
   def delete_upload_files
-    dir = Rails.root.join("public", "system", "uploads", id.to_s)
+    dir = upload_root.join(id.to_s)
     FileUtils.rm_rf(dir) if Dir.exist?(dir)
   end
 
   def file_path(style)
-    Rails.root.join(
-      "public", "system", "uploads",
-      id.to_s, style.to_s, upload_file_name
-    ).to_s
+    upload_root.join(id.to_s, style.to_s, variant_filename(style)).to_s
   end
 
   def sanitize_filename(filename)
-    File.basename(filename).gsub(/[^\w\.\-]/, '_')
+    name = File.basename(filename).unicode_normalize(:nfc)
+    name.gsub(/(?u)[^\w\.\-]/, '_')
   end
 
   # Proxy object returned by asset.upload, providing the Paperclip-compatible
@@ -118,7 +147,7 @@ module FileAttachment
 
     def url(style = :original)
       return "" if @record.upload_file_name.blank?
-      "/system/uploads/#{@record.id}/#{style}/#{@record.upload_file_name}"
+      "/system/uploads/#{@record.id}/#{style}/#{@record.variant_filename(style)}"
     end
 
     def content_type
diff --git a/app/models/node_action.rb b/app/models/node_action.rb
index 13bd5ba..63a99ae 100644
--- a/app/models/node_action.rb
+++ b/app/models/node_action.rb
@@ -166,4 +166,12 @@ class NodeAction < ApplicationRecord
   def subject_name
     metadata["human_readable_node_name"] || node&.unique_name || "deleted node"
   end
+
+  def diff_link_params
+    prev = NodeAction.where(node_id: node_id, action: "publish")
+                     .where("id < ?", id)
+                     .order(id: :desc).first
+    return nil unless prev&.page && page
+    { start_revision: prev.page.revision, end_revision: page.revision }
+  end
 end
diff --git a/app/models/page.rb b/app/models/page.rb
index f33d88d..817e3bd 100644
--- a/app/models/page.rb
+++ b/app/models/page.rb
@@ -220,7 +220,12 @@ class Page < ApplicationRecord
     end
 
     # Clone asset references
-    self.assets = page.assets
+    self.related_assets.delete_all
+    page.related_assets.each do |related|
+      self.related_assets.create!(:asset_id => related.asset_id,
+                                  :position => related.position,
+                                  :headline => related.headline)
+    end
 
     self.save
   end
@@ -287,6 +292,10 @@ class Page < ApplicationRecord
     end
   end
 
+  def headline_asset
+    related_assets.find_by(headline: true)&.asset
+  end
+
   # Returns true if a page has translations where one of them is significantly
   # older than the other.
   # Takes the I18n.default locale and a second :locale to test if the
@@ -314,21 +323,6 @@ class Page < ApplicationRecord
     end
   end
 
-  def update_assets image_ids
-
-    transaction do
-      self.related_assets.delete_all
-
-      if image_ids
-        image_ids.each_with_index do |id, index|
-          asset = Asset.find(id)
-          self.related_assets.create!(:asset_id => asset.id, :position => index+1)
-        end
-      end
-    end
-
-  end
-
   # Installs (or re-installs) the trigger that keeps page_translations'
   # search_vector in sync. Idempotent, safe to call on every boot.
   # search_vector is populated by a raw Postgres trigger, not anything
diff --git a/app/models/related_asset.rb b/app/models/related_asset.rb
index 8f16460..8f8d49c 100644
--- a/app/models/related_asset.rb
+++ b/app/models/related_asset.rb
@@ -5,4 +5,13 @@ class RelatedAsset < ApplicationRecord
   acts_as_list :scope => :page_id
 
   default_scope -> { order("position ASC") }
+
+  validate :headline_only_for_images
+
+  private
+
+    def headline_only_for_images
+      return unless asset
+      errors.add(:headline, "can only be set on image or PDF assets") if headline? && !(asset.image? || asset.pdf?)
+    end
 end
diff --git a/app/views/assets/edit.html.erb b/app/views/assets/edit.html.erb
index f198600..3ef8fea 100644
--- a/app/views/assets/edit.html.erb
+++ b/app/views/assets/edit.html.erb
@@ -1,24 +1,44 @@
-<h1>Editing asset</h1>
+<div id="page_editor">
+  <h1>Editing asset</h1>
 
-<%= form_for(@asset, html: { multipart: true }) do |f| %>
-  <%= form_error_messages(f) %>
+  <%= form_for(@asset, html: { multipart: true }) do |f| %>
+    <%= form_error_messages(f) %>
 
-  <% if @asset.upload.present? %>
-    <p>
-      <strong>Current file:</strong>
-      <%= @asset.upload.url %>
-      (<%= number_to_human_size(@asset.upload.size) %>)
-    </p>
-  <% end %>
+    <div id="content">
+      <div class="node_description"><%= f.label :name %></div>
+      <div class="node_content"><%= f.text_field :name %></div>
+
+      <% if @asset.upload.present? %>
+        <div class="node_description">Current File</div>
+        <div class="node_content"><%= @asset.upload.url %> (<%= number_to_human_size(@asset.upload.size) %>)</div>
+      <% end %>
+
+      <div class="node_description"><%= f.label :upload, "Replace file" %></div>
+      <div class="node_content"><%= f.file_field :upload %></div>
 
-  <p>
-    <label>Replace file:</label><br>
-    <%= f.file_field :upload %>
-  </p>
+      <div class="node_description"><%= f.label :creator %></div>
+      <div class="node_content"><%= f.text_field :creator %></div>
 
-  <p>
-    <%= f.submit 'Update' %>
-  </p>
-<% end %>
+      <div class="node_description"><%= f.label :source_url, "Source URL" %></div>
+      <div class="node_content"><%= f.text_field :source_url %></div>
 
-<%= link_to 'Show', @asset %> | <%= link_to 'Back', assets_path %>
+      <div class="node_description"><%= f.label :license_key, "License" %></div>
+      <div class="node_content">
+        <%= f.select :license_key,
+              options_for_select(
+                [["— none —", ""]] + AssetLicense.keys.map { |key| [t("asset_licenses.#{key}"), key] },
+                @asset.license_key
+              ) %>
+      </div>
+
+      <div class="node_description">Actions</div>
+      <div class="node_content node_info_group">
+        <div class="node_info_group_items">
+          <div class="node_info_item"><%= f.submit 'Update' %></div>
+          <div class="node_info_item"><%= link_to 'Show', @asset %></div>
+          <div class="node_info_item"><%= link_to 'Back', assets_path %></div>
+        </div>
+      </div>
+    </div>
+  <% end %>
+</div>
diff --git a/app/views/assets/index.html.erb b/app/views/assets/index.html.erb
index 8c35561..ff1300a 100644
--- a/app/views/assets/index.html.erb
+++ b/app/views/assets/index.html.erb
@@ -17,7 +17,7 @@
   </tr>
 <% @assets.each do |asset| %>
   <tr>
-    <td><%= image_tag asset.upload.url(:thumb), style: "max-width: 100px; max-height: 100px;" %></td>
+    <td><% if asset.has_variant?(:thumb) %><%= image_tag asset.upload.url(:thumb), style: "max-width: 100px; max-height: 100px;" %><% end %></td>
     <td><%= link_to asset.name, asset.upload.url %></td>
     <td><%= asset.upload.content_type %></td>
     <td><%= link_to 'Show', asset %></td>
diff --git a/app/views/assets/new.html.erb b/app/views/assets/new.html.erb
index 6c1310a..2cf8865 100644
--- a/app/views/assets/new.html.erb
+++ b/app/views/assets/new.html.erb
@@ -1,17 +1,38 @@
-<h1>New asset</h1>
+<div id="page_editor">
+  <h1>New asset</h1>
 
-<%= form_for(@asset, :html => { :multipart => true }) do |f| %>
-  <%= form_error_messages(f) %>
-  
-  <p>
-    <%= f.label :name %><br />
-    <%= f.text_field :name %>
-  </p>
+  <%= form_for(@asset, :html => { :multipart => true }) do |f| %>
+    <%= form_error_messages(f) %>
 
-  <p>
-    <%= f.file_field :upload %>
-    <%= f.submit 'Create' %>
-  </p>
-<% end %>
+    <div id="content">
+      <div class="node_description"><%= f.label :name %></div>
+      <div class="node_content"><%= f.text_field :name %></div>
 
-<%= link_to 'Back', assets_path %>
+      <div class="node_description"><%= f.label :upload, "File" %></div>
+      <div class="node_content"><%= f.file_field :upload %></div>
+
+      <div class="node_description"><%= f.label :creator %></div>
+      <div class="node_content"><%= f.text_field :creator %></div>
+
+      <div class="node_description"><%= f.label :source_url, "Source URL" %></div>
+      <div class="node_content"><%= f.text_field :source_url %></div>
+
+      <div class="node_description"><%= f.label :license_key, "License" %></div>
+      <div class="node_content">
+        <%= f.select :license_key,
+              options_for_select(
+                [["— none —", ""]] + AssetLicense.keys.map { |key| [t("asset_licenses.#{key}"), key] },
+                @asset.license_key
+              ) %>
+      </div>
+
+      <div class="node_description">Actions</div>
+      <div class="node_content node_info_group">
+        <div class="node_info_group_items">
+          <div class="node_info_item"><%= f.submit 'Create' %></div>
+          <div class="node_info_item"><%= link_to 'Back', assets_path %></div>
+        </div>
+      </div>
+    </div>
+  <% end %>
+</div>
diff --git a/app/views/assets/show.html.erb b/app/views/assets/show.html.erb
index 5717dd9..e551e35 100644
--- a/app/views/assets/show.html.erb
+++ b/app/views/assets/show.html.erb
@@ -16,11 +16,42 @@
       </div>
     </div>
 
-    <div class="node_description">Thumbnail</div>
-    <div class="node_content"><%= image_tag @asset.upload.url(:medium), style: "max-width: 300px; max-height: 300px;" %></div>
+    <% if @asset.has_variant?(:medium) %>
+      <div class="node_description">Thumbnail</div>
+      <div class="node_content"><%= image_tag @asset.upload.url(:medium), style: "max-width: 300px; max-height: 300px;" %></div>
+    <% end %>
 
     <div class="node_description">Public Path</div>
-    <div class="node_content"><%= @asset.upload.url.sub(/\?\d+$/, "") %></div>
+    <div class="node_content">
+      <% public_path = @asset.upload.url.sub(/\?\d+$/, "") %>
+      <%= link_to public_path, public_path, target: "_blank", rel: "noopener" %>
+      <button type="button" class="action_button copy_button"
+              data-copy-url="<%= request.base_url + public_path %>">
+        <%= icon("copy", library: "tabler", "aria-hidden": true) %>
+        <span class="copy_button_label">Copy URL</span>
+      </button>
+    </div>
+
+    <div class="node_description">Creator</div>
+    <div class="node_content"><%= @asset.creator.presence || "—" %></div>
+
+    <div class="node_description">Source</div>
+    <div class="node_content">
+      <% if @asset.source_url.present? %>
+        <%= link_to @asset.source_url, @asset.source_url %>
+      <% else %>
+        —
+      <% end %>
+    </div>
+
+    <div class="node_description">License</div>
+    <div class="node_content">
+      <% if (license = AssetLicense.find(@asset.license_key)) %>
+        <%= t("asset_licenses.#{license.key}") %>
+      <% else %>
+        —
+      <% end %>
+    </div>
 
     <div class="node_description">Content Type</div>
     <div class="node_content"><%= @asset.upload.content_type %></div>
diff --git a/app/views/content/_asset_credits.html.erb b/app/views/content/_asset_credits.html.erb
new file mode 100644
index 0000000..5959abd
--- /dev/null
+++ b/app/views/content/_asset_credits.html.erb
@@ -0,0 +1,10 @@
+<% if @page.assets.images.any? %>
+  <div id="asset_credits">
+    <% @page.assets.images.each do |image| %>
+      <div id="credit_for_asset_<%= image.id %>"
+          class="asset_credit_block<%= " headline_credit" if image == @headline_asset %>">
+        <%= asset_credit(image) %>
+      </div>
+    <% end %>
+  </div>
+<% end %>
diff --git a/app/views/content/_headline_image.html.erb b/app/views/content/_headline_image.html.erb
index 243be40..4a3dfdc 100644
--- a/app/views/content/_headline_image.html.erb
+++ b/app/views/content/_headline_image.html.erb
@@ -1,16 +1,59 @@
-<%= link_to(
-  image_tag(@images[0].upload.url(:headline)),
-  @images[0].upload.url,
-  :class => "glightbox",
-  :data  => { :gallery => "page-#{@page.node.id}" }
-) %>
+<% gallery_images = @page.assets.images %>
+<% image_headline = @headline_asset if @headline_asset&.image? %>
+<% other_pdfs = @page.assets.pdfs.where.not(id: @headline_asset&.id) %>
 
-<% if 1 < @images.length %>
-  <div class="right">
-    <%= "#{@images.length} #{t(:images)}" %>
-  </div>
+<% if @headline_asset&.pdf? %>
+  <%= link_to @headline_asset.upload.url, :class => "headline_document_card", :target => "_blank", :rel => "noopener" do %>
+    <%= image_tag @headline_asset.upload.url(:medium), :alt => "", :class => "headline_document_card_thumb" %>
+    <div class="headline_document_card_info">
+      <%= icon("file-text", library: "tabler", "aria-hidden": true) %>
+      <span class="headline_document_card_title"><%= @headline_asset.name %></span>
+    </div>
+  <% end %>
+<% end %>
+
+<% if image_headline %>
+  <%= link_to(
+    image_tag(image_headline.upload.url(:headline)),
+    image_headline.upload.url,
+    :class => "glightbox",
+    :data => { :gallery => "page-#{@page.node.id}",
+               :glightbox => glightbox_data(image_headline, image_headline.name),
+               :"credit-selector" => (image_headline.show_credit? ? "#credit_for_asset_#{image_headline.id}" : nil) }
+  ) %>
+  <% if gallery_images.size > 1 %>
+    <div class="right"><%= "#{gallery_images.size} #{t(:images)}" %></div>
+  <% end %>
+<% elsif gallery_images.any? %>
+  <%= link_to "#{gallery_images.size} #{t(:images)}, #{t(:open_gallery)}",
+        gallery_images.first.upload.url,
+        :class => "glightbox right",
+        :data => { :gallery => "page-#{@page.node.id}",
+                   :glightbox => glightbox_data(gallery_images.first, gallery_images.first.name),
+                   :"credit-selector" => (gallery_images.first.show_credit? ? "#credit_for_asset_#{gallery_images.first.id}" : nil) } %>
 <% end %>
 
-<% @images[1..-1].each do |image| %>
-  <%= link_to "", image.upload.url, :class => "glightbox", :style => "display: none", :data => { :gallery => "page-#{@page.node.id}" } %>
+<% gallery_images.each do |image| %>
+  <% next if image == image_headline %>
+  <% next if !image_headline && image == gallery_images.first %>
+  <%= link_to "", image.upload.url, :class => "glightbox", :style => "display: none",
+        :data => { :gallery => "page-#{@page.node.id}",
+                   :glightbox => glightbox_data(image, image.name),
+                   :"credit-selector" => (image.show_credit? ? "#credit_for_asset_#{image.id}" : nil) } %>
+<% end %>
+
+<% if other_pdfs.any? %>
+  <div class="related_documents">
+    <div class="related_documents_label"><%= t(:related_documents) %></div>
+    <ul class="related_documents_list">
+      <% other_pdfs.each do |pdf| %>
+        <li>
+          <%= link_to pdf.upload.url, :class => "related_document_link", :target => "_blank", :rel => "noopener" do %>
+            <%= icon("file-text", library: "tabler", "aria-hidden": true) %>
+            <span><%= pdf.name %></span>
+          <% end %>
+        </li>
+      <% end %>
+    </ul>
+  </div>
 <% end %>
diff --git a/app/views/custom/page_templates/public/chapter_detail.html.erb b/app/views/custom/page_templates/public/chapter_detail.html.erb
index c4c2598..18449b8 100644
--- a/app/views/custom/page_templates/public/chapter_detail.html.erb
+++ b/app/views/custom/page_templates/public/chapter_detail.html.erb
@@ -31,4 +31,5 @@
       </ul>
     </div>
   <% end %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
diff --git a/app/views/custom/page_templates/public/no_date_and_author.html.erb b/app/views/custom/page_templates/public/no_date_and_author.html.erb
index fa39e54..ec7e850 100644
--- a/app/views/custom/page_templates/public/no_date_and_author.html.erb
+++ b/app/views/custom/page_templates/public/no_date_and_author.html.erb
@@ -3,6 +3,7 @@
   <p><%= sanitize( @page.abstract ) %></p>
   <div id="headline_image"><%= headline_image %></div>
   <%= aggregate?(@page.body) %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb b/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb
index 64e2a7c..c486684 100644
--- a/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb
+++ b/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb
@@ -1,6 +1,7 @@
 <div class="article" lang="<%= @page.effective_lang %>">
   <div id="headline_image"><%= headline_image %></div>
   <%= aggregate?(@page.body) %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/standard_template.html.erb b/app/views/custom/page_templates/public/standard_template.html.erb
index bbc8cd0..e1e2eb0 100644
--- a/app/views/custom/page_templates/public/standard_template.html.erb
+++ b/app/views/custom/page_templates/public/standard_template.html.erb
@@ -3,6 +3,7 @@
   <div class="abstract"><p><%= sanitize( @page.abstract )%></p></div>
   <div id="headline_image"><%= headline_image %></div>
   <div class="body"><%= aggregate?(@page.body) %></div>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/title_only.html.erb b/app/views/custom/page_templates/public/title_only.html.erb
index 42fe9a6..d706e9d 100644
--- a/app/views/custom/page_templates/public/title_only.html.erb
+++ b/app/views/custom/page_templates/public/title_only.html.erb
@@ -2,6 +2,7 @@
   <h2 class="headline"><%= @page.title %></h2>
   <div id="headline_image"><%= headline_image %></div>
   <%= aggregate?(@page.body) %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/update.html.erb b/app/views/custom/page_templates/public/update.html.erb
index d5995ac..0ff1bb2 100644
--- a/app/views/custom/page_templates/public/update.html.erb
+++ b/app/views/custom/page_templates/public/update.html.erb
@@ -4,6 +4,7 @@
   <div class="abstract"><p><%= sanitize( @page.abstract )%></p></div>
   <div id="headline_image"><%= headline_image %></div>
   <div class="body"><%= aggregate?(@page.body) %></div>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/partials/_chapter.html.erb b/app/views/custom/partials/_chapter.html.erb
index 47f3950..5d47679 100644
--- a/app/views/custom/partials/_chapter.html.erb
+++ b/app/views/custom/partials/_chapter.html.erb
@@ -1,7 +1,7 @@
 <div class="article_partial chapter_partial" lang="<%= page.effective_lang %>">
   <div class="chapter_partial_layout">
-    <% if page.assets.images.any? %>
-      <%= link_to_path image_tag(page.assets.images.first.upload.url(:thumb), :alt => ""), page.node.unique_name, class: "chapter_thumbnail" %>
+    <% if page.headline_asset %>
+      <%= link_to_path image_tag(page.headline_asset.upload.url(:thumb), :alt => ""), page.node.unique_name, class: "chapter_thumbnail" %>
     <% end %>
     <div class="chapter_partial_content">
       <h2 class="headline"><%= link_to_path page.title, page.node.unique_name %></h2>
diff --git a/app/views/layouts/application.html.erb b/app/views/layouts/application.html.erb
index 352fb66..f981fc1 100644
--- a/app/views/layouts/application.html.erb
+++ b/app/views/layouts/application.html.erb
@@ -10,7 +10,7 @@
     <meta property="og:description" content="Der Chaos Computer Club ist eine galaktische Gemeinschaft von Lebewesen für Informationsfreiheit und Technikfolgenabschätzung." />
 
     <title><%= page_title %></title>
-    <link rel="stylesheet" href="<%= mtime_busted_path('/stylesheets/ccc_new.css') %>">
+    <link rel="stylesheet" href="<%= mtime_busted_path('/stylesheets/ccc.css') %>">
     <link rel="stylesheet" href="<%= mtime_busted_path('/stylesheets/glightbox.min.css') %>">
     <script src="<%= mtime_busted_path('/javascripts/glightbox.min.js') %>"></script>
     <script src="<%= mtime_busted_path('/javascripts/public.js') %>"></script>
diff --git a/app/views/layouts/events.html.erb b/app/views/layouts/events.html.erb
deleted file mode 100644
index 93a6c0c..0000000
--- a/app/views/layouts/events.html.erb
+++ /dev/null
@@ -1,17 +0,0 @@
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
-       "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
-
-<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
-<head>
-  <meta http-equiv="content-type" content="text/html;charset=UTF-8" />
-  <title>Events: <%= controller.action_name %></title>
-  <%= stylesheet_link_tag 'scaffold' %>
-</head>
-<body>
-
-<p style="color: green"><%= flash[:notice] %></p>
-
-<%= yield %>
-
-</body>
-</html>
diff --git a/app/views/node_actions/_change_details.html.erb b/app/views/node_actions/_change_details.html.erb
index 2583e8b..066d0f3 100644
--- a/app/views/node_actions/_change_details.html.erb
+++ b/app/views/node_actions/_change_details.html.erb
@@ -5,9 +5,13 @@
       <tr>
         <th><%= I18n.default_locale.to_s.upcase %></th>
         <td>
-          <%= safe_join(default_items, ", ") %>
+          <%= safe_join(default_items, tag.br) %>
           <% if action_entry.page && action_entry.node %>
-            <%= link_to t("node_actions.view_revision"), node_revision_path(action_entry.node, action_entry.page) %>
+            <% if (diff_params = action_entry.diff_link_params) %>
+              <%= link_to t("node_actions.view_diff"), diff_node_revisions_path(action_entry.node, diff_params) %>
+            <% else %>
+              <%= link_to t("node_actions.view_revision"), node_revision_path(action_entry.node, action_entry.page) %>
+            <% end %>
           <% end %>
         </td>
       </tr>
@@ -16,9 +20,13 @@
       <tr>
         <th><%= locale.upcase %></th>
         <td>
-          <%= safe_join(translation_changes(diff), ", ") %>
+          <%= safe_join(translation_changes(diff), tag.br) %>
           <% if action_entry.page && action_entry.node %>
-            <%= link_to t("node_actions.view_revision"), node_revision_path(action_entry.node, action_entry.page, :locale => locale) %>
+            <% if (diff_params = action_entry.diff_link_params) %>
+              <%= link_to t("node_actions.view_diff"), diff_node_revisions_path(action_entry.node, diff_params.merge(:locale => locale)) %>
+            <% else %>
+              <%= link_to t("node_actions.view_revision"), node_revision_path(action_entry.node, action_entry.page, :locale => locale) %>
+            <% end %>
           <% end %>
         </td>
       </tr>
diff --git a/app/views/nodes/edit.html.erb b/app/views/nodes/edit.html.erb
index 25f15c2..12dc000 100644
--- a/app/views/nodes/edit.html.erb
+++ b/app/views/nodes/edit.html.erb
@@ -82,17 +82,27 @@
           <ul id="related_asset_list" class="thumbnail_list">
             <% @page.related_assets.includes(:asset).each do |related| %>
               <li data-url="<%= node_related_asset_path(@node, related) %>"
+                  data-asset-id="<%= related.asset.id %>"
                   data-large-url="<%= related.asset.upload.url(:large) %>"
                   data-original-url="<%= related.asset.upload.url %>"
-                  data-name="<%= related.asset.name %>">
+                  data-name="<%= related.asset.name %>"
+                  data-has-credit="<%= related.asset.show_credit? %>"
+                  data-headline="<%= related.headline? %>"
+                  class="<%= "is_headline" if related.headline? %>">
                 <span class="related_asset_handle"><%= icon("grip-vertical", library: "tabler", "aria-hidden": true) %></span>
                 <%= image_tag related.asset.upload.url(:thumb) %>
+                <button type="button" class="related_asset_set_headline"
+                        aria-pressed="<%= related.headline? %>" aria-label="Set as headline image"
+                        title="Use this photo as the page's headline image">
+                  <%= icon("star", library: "tabler", "aria-hidden": true) %>
+                </button>
                 <button type="button" class="related_asset_remove" aria-label="Remove image">
                   <%= icon("x", library: "tabler", "aria-hidden": true) %>
                 </button>
               </li>
             <% end %>
           </ul>
+          <p class="field_hint">The starred image or PDF becomes this page's headline on the public site. If none is starred, visitors get a link to browse all attached images instead.</p>
           <%= text_field_tag nil, nil, id: "related_asset_search_term", placeholder: "Search images to attach…", autocomplete: "off" %>
           <div id="related_asset_search_results" class="search_results"></div>
         </div>
@@ -102,6 +112,9 @@
         <li>
           <span class="related_asset_handle"><%= icon("grip-vertical", library: "tabler", "aria-hidden": true) %></span>
           <img src="">
+          <button type="button" class="related_asset_set_headline" aria-pressed="false" aria-label="Set as headline image">
+            <%= icon("star", library: "tabler", "aria-hidden": true) %>
+          </button>
           <button type="button" class="related_asset_remove" aria-label="Remove image">
             <%= icon("x", library: "tabler", "aria-hidden": true) %>
           </button>
diff --git a/app/views/nodes/new.html.erb b/app/views/nodes/new.html.erb
index 890d46e..805fbc9 100644
--- a/app/views/nodes/new.html.erb
+++ b/app/views/nodes/new.html.erb
@@ -41,7 +41,10 @@
   <div class="node_description">Resulting path</div>
   <div class="node_content">
     <span id="resulting_path">—</span>
-    <button type="button" id="copy_resulting_path" class="unselected">copy</button>
+    <button type="button" id="copy_resulting_path" class="unselected copy_button" data-copy-target="#resulting_path">
+      <span class="copy_button_label">copy</span>
+    </button>
+
     <span class="field_hint">This preview updates as you type. The final path can still be changed afterward by editing the title (for the last segment) or moving the node to a different parent (for everything before it).</span>
   </div>
 
diff --git a/app/views/nodes/show.html.erb b/app/views/nodes/show.html.erb
index af05778..adf79dd 100644
--- a/app/views/nodes/show.html.erb
+++ b/app/views/nodes/show.html.erb
@@ -253,12 +253,20 @@
       <% end %>
     </div>
 
-    <% if @page.assets.images.any? %>
+    <% if @page.assets.any? %>
+      <% headline_asset_id = @page.headline_asset&.id %>
       <div class="node_description">Images</div>
       <div class="node_content node_info_group">
         <ul class="thumbnail_list">
-          <% @page.assets.images.each do |asset| %>
-            <li><%= link_to image_tag(asset.upload.url(:thumb)), asset_path(asset) %></li>
+          <% @page.assets.each do |asset| %>
+            <li class="<%= "is_headline" if asset.id == headline_asset_id %>">
+              <%= link_to image_tag(asset.upload.url(:thumb)), asset_path(asset) %>
+              <% if asset.id == headline_asset_id %>
+                <span class="headline_indicator" title="This page's headline image">
+                  <%= icon("star", library: "tabler", "aria-hidden": true) %>
+                </span>
+              <% end %>
+            </li>
           <% end %>
         </ul>
       </div>