fixes #80: Clicking Pixiv source address at the information panel

app/helpers/posts_helper.rb

@@ -23,8 +23,8 @@ module PostsHelper
   
   def post_source_tag(post)
     if post.source =~ /^http/
-      text = truncate(post.source.sub(/^https?:\/\//, ""))
-      link_to(truncate(text, :length => 15), post.source)
+      text = truncate(post.normalized_source.sub(/^https?:\/\//, ""))
+      link_to(truncate(text, :length => 15), post.normalized_source)
     else
       truncate(post.source, :length => 100)
     end

app/models/post.rb

@@ -319,6 +319,20 @@ class Post < ActiveRecord::Base
         "Safe"
       end
     end
+    
+    def normalized_source
+      if source =~ /pixiv\.net\/img\//
+        img_id = source[/(\d+)(_s|_m|(_big)?_p\d+)?\.[\w\?]+\s*$/, 1]
+
+        if $2 =~ /_p/
+          "http://www.pixiv.net/member_illust.php?mode=manga&illust_id=#{img_id}"
+        else
+          "http://www.pixiv.net/member_illust.php?mode=medium&illust_id=#{img_id}"
+        end
+      else
+        source
+      end
+    end
   end
   
   module TagMethods