fixes #858

adds color coding to both urls and other names on artist versions

app/assets/stylesheets/specific/posts.css.scss

@@ -286,7 +286,7 @@ div#c-posts {
   }
 }
 
-div#c-post-versions {
+div#c-post-versions, div#c-artist-versions {
   div#a-index {
     a {
       word-wrap: break-word

app/helpers/artist_versions_helper.rb

@@ -1,2 +1,31 @@
 module ArtistVersionsHelper
+  def artist_version_other_names_diff(artist_version)
+    diff = artist_version.other_names_diff(artist_version.previous)
+    html = []
+    diff[:added_names].each do |name|
+      html << '<ins>' + name + '</ins>'
+    end
+    diff[:removed_names].each do |name|
+      html << '<del>' + name + '</del>'
+    end
+    diff[:unchanged_names].each do |name|
+      html << '<span>' + name + '</span>'
+    end
+    return html.join(" ").html_safe
+  end
+
+  def artist_version_urls_diff(artist_version)
+    diff = artist_version.urls_diff(artist_version.previous)
+    html = []
+    diff[:added_urls].each do |url|
+      html << '<li><ins>' + url + '</ins></li>'
+    end
+    diff[:removed_urls].each do |url|
+      html << '<li><del>' + url + '</del></li>'
+    end
+    diff[:unchanged_urls].each do |url|
+      html << '<li><span>' + url + '</span></li>'
+    end
+    return html.join(" ").html_safe
+  end
 end

app/models/artist_version.rb

@@ -27,6 +27,36 @@ class ArtistVersion < ActiveRecord::Base
     url_string.scan(/\S+/)
   end
 
+  def other_names_array
+    other_names.scan(/\S+/)
+  end
+
+  def urls_diff(version)
+    new_urls = url_array
+    old_urls = version.present? ? version.url_array : []
+
+    return {
+      :added_urls => new_urls - old_urls,
+      :removed_urls => old_urls - new_urls,
+      :unchanged_urls => new_urls & old_urls,
+    }
+  end
+
+  def other_names_diff(version)
+    new_names = other_names_array
+    old_names = version.present? ? version.other_names_array : []
+
+    return {
+      :added_names => new_names - old_names,
+      :removed_names => old_names - new_names,
+      :unchanged_names => new_names & old_names,
+    }
+  end
+
+  def previous
+    ArtistVersion.where("artist_id = ? and updated_at < ?", artist_id, updated_at).order("updated_at desc").first
+  end
+
   def updater_name
     User.id_to_name(updater_id).tr("_", " ")
   end

app/views/artist_versions/index.html.erb

@@ -24,16 +24,14 @@
                 <%= link_to artist_version.name, artist_versions_path(:search => {:artist_id => artist_version.artist_id}) %>
               </td>
               <td><%= link_to "artist", artist_path(artist_version.artist) %></td>
-              <td><%= artist_version.other_names %></td>
+              <td><%= artist_version_other_names_diff(artist_version) %></td>
               <td><%= artist_version.group_name %></td>
               <td><%= compact_time artist_version.created_at %></td>
               <td><%= link_to artist_version.updater_name, user_path(artist_version.updater_id) %></td>
               <td><%= artist_version.is_active? %></td>
               <td>
                 <ul>
-                  <% artist_version.url_array.each do |url| %>
-                    <li><%= url %></li>
-                  <% end %>
+                  <%= artist_version_urls_diff(artist_version) %>
                 </ul>
               </td>
               <td>