nijie: convert commentary to dtext.

app/logical/sources/strategies/nijie.rb

@@ -44,6 +44,28 @@ module Sources
 
     protected
 
+      # XXX: duplicated from strategies/deviant_art.rb.
+      def self.to_dtext(text)
+        html = Nokogiri::HTML.fragment(text)
+
+        dtext = html.children.map do |element|
+          case element.name
+          when "text"
+            element.content
+          when "strong"
+            "[b]#{to_dtext(element.inner_html)}[/b]" if element.inner_html.present?
+          when "i"
+            "[i]#{to_dtext(element.inner_html)}[/i]" if element.inner_html.present?
+          when "s"
+            "[s]#{to_dtext(element.inner_html)}[/s]" if element.inner_html.present?
+          else
+            to_dtext(element.inner_html)
+          end
+        end.join
+
+        dtext
+      end
+
       def get_commentary_from_page(page)
         title = page.search("h2.illust_title").text
         desc = page.search('meta[property="og:description"]').attr("content").value