#1866: Support deviantart source rewriting

* html work page -> full image
* thumbnail -> full image

app/logical/downloads/strategies/base.rb

@@ -2,7 +2,7 @@ module Downloads
   module Strategies
     class Base
       def self.strategies
-        [Pixiv, Twitpic]
+        [Pixiv, Twitpic, DeviantArt]
       end
 
       def rewrite(url, headers)

app/logical/downloads/strategies/deviant_art.rb

@@ -0,0 +1,34 @@
+module Downloads
+  module Strategies
+    class DeviantArt < Base
+      def rewrite(url, headers)
+        if url =~ /https?:\/\/(?:\w+\.)?deviantart\.(?:com|net)/
+          url, headers = rewrite_html_pages(url, headers)
+          url, headers = rewrite_thumbnails(url, headers)
+        end
+
+        return [url, headers]
+      end
+
+    protected
+      def rewrite_html_pages(url, headers)
+        if url =~ %r{^http://\w+\.deviantart\.com/art/\w+}
+          source = ::Sources::Strategies::DeviantArt.new(url)
+          source.get
+          return [source.image_url, headers]
+        else
+          return [url, headers]
+        end
+      end
+
+      def rewrite_thumbnails(url, headers)
+        if url =~ %r{^(http://\w+.deviantart.net/\w+/)200H/}
+          match = $1
+          url.sub!(match + "200H/", match)
+        end
+
+        return [url, headers]
+      end
+    end
+  end
+end