(function ($) {

  "use strict";
  
  Drupal.behaviors.diffRevisions = {
    attach: function (context, settings) {
      var $rows = $('table.diff-revisions tbody tr');
      function updateDiffRadios() {
        var newTd = false;
        var oldTd = false;
        if (!$rows.length) {
          return true;
        }
        $rows.removeClass('selected').each(function() {
          var $row = $(this);
          $row.removeClass('selected');
          var $inputs = $row.find('input[type="radio"]');
          var $oldRadio = $inputs.filter('[name="old"]').eq(0);
          var $newRadio = $inputs.filter('[name="new"]').eq(0);
          if (!$oldRadio.length || !$newRadio.length) {
            return true;
          }
          if ($oldRadio.attr('checked')) {
            oldTd = true;
            $row.addClass('selected');
            $oldRadio.css('visibility', 'visible');
            $newRadio.css('visibility', 'hidden');
          }
          else if ($newRadio.attr('checked')) {
            newTd = true;
            $row.addClass('selected');
            $oldRadio.css('visibility', 'hidden');
            $newRadio.css('visibility', 'visible');
          }
          else {
            if (Drupal.settings.diffRevisionRadios == 'linear') {
              if (newTd && oldTd) {
                $oldRadio.css('visibility', 'visible');
                $newRadio.css('visibility', 'hidden');
              }
              else if (newTd) {
                $newRadio.css('visibility', 'visible');
                $oldRadio.css('visibility', 'visible');
              }
              else {
                $newRadio.css('visibility', 'visible');
                $oldRadio.css('visibility', 'hidden');
              }
            }
            else {
              $newRadio.css('visibility', 'visible');
              $oldRadio.css('visibility', 'visible');
            }
          }
        });
        return true;
      }
      if (Drupal.settings.diffRevisionRadios) {
        $rows.find('input[name="new"], input[name="old"]').click(updateDiffRadios);
        updateDiffRadios();
      }
    }
  };

})(jQuery);