module Admin::RegionsHelper

def lazy_initialize_region_set
  unless @region_set
    @controller_name ||= @_controller.controller_name
    @template_name ||= @_controller.template_name
    @region_set = admin.send(@controller_name).send(@template_name)
  end
end

def render_region(region, options = {}, &block)
  lazy_initialize_region_set
  default_partials = TrustyCms::AdminUI::RegionPartials.new(self)
  if block_given?
    block.call(default_partials)
    (options[:locals] ||= {}).merge!(defaults: default_partials)
  end
  output = @region_set[region].compact.map do |partial|
    begin
      render options.merge(partial: partial)
    rescue ::ActionView::MissingTemplate # couldn't find template
      default_partials[partial]
    rescue ::ActionView::TemplateError => e # error in template
      raise e
    end
  end.join.html_safe
  Rails.logger.error(output)
  block_given? ? concat(output) : output
end