require 'pathname'
 
 module Jekyll
 
   class IncludeCodeTag < Liquid::Tag
     def initialize(tag_name, file, tokens)
       super
       @file = file.strip
     end
 
     def render(context)
       code_dir = (context.registers[:site].config['code_dir'] || 'downloads/code')
       code_path = (Pathname.new(context.registers[:site].source) + code_dir).expand_path
       file = code_path + @file
 
       if File.symlink?(code_path)
         return "Code directory '#{code_path}' cannot be a symlink"
       end
 
       unless file.file?
         return "File #{file} could not be found"
       end
 
       Dir.chdir(code_path) do
         code = file.read
         file_type = file.extname
         url = "#{context.registers[:site].config['url']}/#{code_dir}/#{@file}"

         source = "<figure><figcaption><span>#{file.basename}</span> <a href='#{url}'>download</a></figcaption>\n"

         source += "{% highlight #{file_type} %}\n" + code + "\n{% endhighlight %}</figure>"
         partial = Liquid::Template.parse(source)
         context.stack do
           partial.render(context)
         end
       end
     end
   end
 
 end
 
 Liquid::Template.register_tag('include_code', Jekyll::IncludeCodeTag)