Mailer Viewer inside Rails application

mailers_controller.rb

class MailersController < Admin::BaseController

  def render_layout
    # received params
    # params[:mailer_type]
    # params[:email_template]
    # params[:email_format]
    mailer_type = params[:mailer_type].camelize
    mailer_template = params[:email_template]
    type_class = mailer_type.classify.safe_constantize
    case params[:mailer_type]
      when 'sample_mailer'
        type_class.send(mailer_template(param_1, param_2))
      when 'user_mailer'
        type_class.send(mailer_template(param_1))
      else
        type_class.send(mailer_template)
        logger.debug "No"
    end
    respond_to do |format|
      format.html { render "#{params[:mailer_type]}/#{params[:email_template]}" }
      format.text { render "#{params[:mailer_type]}/#{params[:email_template]}" }
    end
  end

end

routes.rb

    # View email inside Project
    match 'email/:mailer_type/:email_template.:email_format', to: 'mailers#render_layout', via: 'get'