module Nifty
  module Attachments
    class Middleware

      def initialize(app)
        @app = app
      end

      def call(env)
        if env['PATH_INFO'] =~ /\A\/attachment\/([a-f0-9\-]{36})\/(.*)/
          if attachment = Nifty::Attachments::Attachment.find_by_token($1)
            [200, {
              'Content-Length' => attachment.data.bytesize.to_s,
              'Content-Type' => attachment.file_type,
              'Cache-Control' => "public, maxage=#{1.year.to_i}",
              'Content-Disposition' => "attachment; filename=\"#{attachment.file_name}\""
              },
            [attachment.data]]
          else
            [404, {}, ["Attachment not found"]]
          end
        else
          @app.call(env)
        end
      end

    end
  end
end