Make headline images explicit, add asset credits

- related_assets gains a `headline` boolean (DB-enforced: at most one
  per page), replacing "first image by position" as the headline
  rule. A rake task backfills the current first image on every live
  head/draft, so nothing changes visually until an editor changes it.
- The image picker sidebar gets a star toggle reflecting the flag;
  the TinyMCE inline-image picker's badge now reads it too, instead
  of assuming position 0.
- No headline chosen (or none attached) now falls back to the
  gallery-count caption itself becoming the lightbox trigger, instead
  of the gallery being unreachable.
- Assets gain creator, source_url, and license_key (against a new
  config/asset_licenses.yml dictionary). asset_credit renders a
  degrading attribution line, reused as a hidden per-image glightbox
  caption so credit is one click away for every image, not only the
  headline's always-visible one.
- Fixed: asset thumbnails rendered unconditionally regardless of
  whether a real variant exists on disk. Asset#has_variant? checks
  file existence, not content type -- some legacy PDFs have real
  pre-rewrite thumbnails a content-type check would have hidden.
- assets#new/edit rebuilt onto the same node_description/node_content
  layout as assets#show, picking up the three new fields in the
  process.

4 files changed, 100 insertions, 35 deletions

diff --git a/app/views/assets/edit.html.erb b/app/views/assets/edit.html.erb
index f1986000..3ef8fea5 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 8c355617..ff1300a2 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 6c1310a7..2cf88650 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 ff00883c..a0e4e464 100644
--- a/app/views/assets/show.html.erb
+++ b/app/views/assets/show.html.erb
@@ -17,7 +17,10 @@
     </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">
@@ -30,6 +33,27 @@
       </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>