Properly indent whole multiline comment in email notification

app/helpers/application_helper.rb

@@ -21,4 +21,8 @@ module ApplicationHelper
     text = capture(&block)
     MKD_RENDERER.render(capture(&block)).html_safe
   end
+
+  def indented(string, width)
+    string.lines.map { |l| "#{' ' * width}#{l}" }.join('')
+  end
 end

app/mailers/user_mailer.rb

@@ -1,5 +1,6 @@
 class UserMailer < ActionMailer::Base
   default :from => "ascii.io <hello@ascii.io>"
+  helper :application
 
   def new_comment_email(user, comment)
     @comment = comment

app/views/user_mailer/new_comment_email.text.erb

@@ -2,7 +2,7 @@ Howdy!
 
 ~<%= @author.nickname %> (<%= profile_url(@author) %>) commented on your asciicast "<%= @asciicast.smart_title %>":
 
-    <%= @comment.body %>
+<%= indented @comment.body, 4 %>
 
 ---
 http://ascii.io/