class GoogleTagManager

# File lib/middleman-google-tag-manager.rb, line 7
def after_configuration
  unless options.container_id
    $stderr.puts 'Google Tag Manager: Please specify a container ID'
    raise ArgumentError, 'No container ID given' if display?
  end
end

# File lib/middleman-google-tag-manager.rb, line 15
    def google_tag_manager
      options = extensions[:google_tag_manager].options
      return unless !legacy_development? || options.development

      @text ||= <<-END.gsub(/^ {8}/, '')
      <!-- Google Tag Manager -->
      <noscript><iframe src="//www.googletagmanager.com/ns.html?id=#{options.container_id}"
      height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
      <script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
      new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
      j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
      '//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
      })(window,document,'script','dataLayer','#{options.container_id}');</script>
      <!-- End Google Tag Manager -->
      END
    end

# File lib/middleman-google-tag-manager.rb, line 33
def legacy_development?
  # Middleman 3.4
  is_development = try(:development?)
  unless is_development.nil?
    return is_development
  end

  # Middleman 4.x
  app.development?
end

# File lib/middleman-google-tag-manager.rb, line 47
def display?
  app.build? || app.development? && options.development
end