(function ($) {

/**
 * Add functionality to the profile drag and drop table.
 *
 * This behavior is dependent on the tableDrag behavior, since it uses the
 * objects initialized in that behavior to update the row. It shows and hides
 * a warning message when removing the last field from a profile category.
 */
Drupal.behaviors.profileDrag = {
  attach: function (context, settings) {
    var table = $('#profile-fields');
    var tableDrag = Drupal.tableDrag['profile-fields']; // Get the profile tableDrag object.

    // Add a handler for when a row is swapped, update empty categories.
    tableDrag.row.prototype.onSwap = function (swappedRow) {
      var rowObject = this;
      $('tr.category-message', table).each(function () {
        // If the dragged row is in this category, but above the message row, swap it down one space.
        if ($(this).prev('tr').get(0) == rowObject.element) {
          // Prevent a recursion problem when using the keyboard to move rows up.
          if ((rowObject.method != 'keyboard' || rowObject.direction == 'down')) {
            rowObject.swap('after', this);
          }
        }
        // This category has become empty
        if ($(this).next('tr').is(':not(.draggable)') || $(this).next('tr').length == 0) {
          $(this).removeClass('category-populated').addClass('category-empty');
        }
        // This category has become populated.
        else if ($(this).is('.category-empty')) {
          $(this).removeClass('category-empty').addClass('category-populated');
        }
      });
    };

    // Add a handler so when a row is dropped, update fields dropped into new categories.
    tableDrag.onDrop = function () {
      dragObject = this;
      if ($(dragObject.rowObject.element).prev('tr').is('.category-message')) {
        var categoryRow = $(dragObject.rowObject.element).prev('tr').get(0);
        var categoryNum = categoryRow.className.replace(/([^ ]+[ ]+)*category-([^ ]+)-message([ ]+[^ ]+)*/, '$2');
        var categoryField = $('select.profile-category', dragObject.rowObject.element);
        var weightField = $('select.profile-weight', dragObject.rowObject.element);
        var oldcategoryNum = weightField[0].className.replace(/([^ ]+[ ]+)*profile-weight-([^ ]+)([ ]+[^ ]+)*/, '$2');

        if (!categoryField.is('.profile-category-' + categoryNum)) {
          categoryField.removeClass('profile-category-' + oldcategoryNum).addClass('profile-category-' + categoryNum);
          weightField.removeClass('profile-weight-' + oldcategoryNum).addClass('profile-weight-' + categoryNum);

          categoryField.val(categoryField[0].options[categoryNum].value);
        }
      }
    };
  }
};

})(jQuery);