huginn/app/views/system_mailer/send_message.text.erb

<% if @body.present? %><%= sanitize @body -%>
<% else -%>
<% if @headline %><%= @headline %>

<% end %><% @groups.each do |group| %><%= group[:title] %>
<% group[:entries].each do |entry| %>  <%= entry %>
<% end %>

<% end %>
<% end %>