Make the artist finder work with new Pixiv URLs.

app/controllers/artists_controller.rb

@@ -118,11 +118,7 @@ class ArtistsController < ApplicationController
   end
 
   def finder
-    url = params[:url]
-    headers = {
-      "User-Agent" => "#{Danbooru.config.safe_app_name}/#{Danbooru.config.version}"
-    }
-    url, headers = Downloads::Strategies::Pixiv.new.rewrite(url, headers)
+    url = Sources::Strategies::Pixiv.new(url).normalize_for_artist_finder!(params[:url])
 
     @artists = Artist.url_matches(url).order("id desc").limit(20)
     respond_with(@artists) do |format|

app/logical/sources/strategies/pixiv.rb

@@ -25,6 +25,21 @@ module Sources
         @pixiv_moniker
       end
 
+      def normalize_for_artist_finder!(url)
+        illust_id = illust_id_from_url(url)
+
+        # http://i2.pixiv.net/img04/img/syounen_no_uta/46170939_m.jpg
+        if url =~ %r!/img/([^/]+)/\d+(?:_\w+)?\.(?:jpg|jpeg|png|gif)!i
+          username = $1
+        else
+          get_metadata_from_spapi!(illust_id) do |metadata|
+            username = metadata[24]
+          end
+        end
+
+        "http://img.pixiv.net/img/#{username}"
+      end
+
       def get
         agent.get(URI.parse(normalized_url)) do |page|
           @artist_name, @profile_url = get_profile_from_page(page)