Rest_BBP_Walker_Reply

class Rest_BBP_Walker_Reply extends Walker {

	/**
	 * @see Walker::$tree_type
	 *
	 * @since 2.4.0 bbPress (r4944)
	 *
	 * @var string
	 */
	public $tree_type = 'reply';

	/**
	 * @see Walker::$db_fields
	 *
	 * @since 2.4.0 bbPress (r4944)
	 *
	 * @var array
	 */
	public $db_fields = array(
		'parent' => 'reply_to',
		'id'     => 'ID',
	);

	/**
	 * Confirm the tree_type
	 *
	 * @since 2.6.0 bbPress (r5389)
	 */
	public function __construct() {
		$this->tree_type = bbp_get_reply_post_type();
	}

	/**
	 * @see Walker::start_lvl()
	 *
	 * @since 2.4.0 bbPress (r4944)
	 *
	 * @param string $output Passed by reference. Used to append additional content
	 * @param int    $depth Depth of reply
	 * @param array  $args Uses 'style' argument for type of HTML list
	 */
	public function start_lvl( &$output = '', $depth = 0, $args = array() ) {
		bbpress()->reply_query->reply_depth = (int) $depth + 1;
	}

	/**
	 * @see Walker::end_lvl()
	 *
	 * @since 2.4.0 bbPress (r4944)
	 *
	 * @param string $output Passed by reference. Used to append additional content
	 * @param int    $depth Depth of reply
	 * @param array  $args Will only append content if style argument value is 'ol' or 'ul'
	 */
	public function end_lvl( &$output = '', $depth = 0, $args = array() ) {
		bbpress()->reply_query->reply_depth = (int) $depth + 1;
	}

	/**
	 * @since 2.4.0 bbPress (r4944)
	 */
	public function display_element( $element = false, &$children_elements = array(), $max_depth = 0, $depth = 0, $args = array(), &$output = '' ) {

		if ( empty( $element ) ) {
			return;
		}

		// Get element's id
		$id_field = $this->db_fields['id'];
		$id       = $element->$id_field;

		// Display element
		parent::display_element( $element, $children_elements, $max_depth, $depth, $args, $output );

		// If we're at the max depth and the current element still has children, loop over those
		// and display them at this level to prevent them being orphaned to the end of the list.
		if ( ( $max_depth <= (int) $depth + 1 ) && isset( $children_elements[ $id ] ) ) {
			foreach ( $children_elements[ $id ] as $child ) {
				$this->display_element( $child, $children_elements, $max_depth, $depth, $args, $output );
			}
			unset( $children_elements[ $id ] );
		}
	}

	/**
	 * @see Walker:start_el()
	 *
	 * @since 2.4.0 bbPress (r4944)
	 */
	public function start_el( &$output, $object, $depth = 0, $args = array(), $current_object_id = 0 ) {
		global $buddyboss_thread_reply;

		// Set up reply
		$depth++;
		$object->depth                         = $depth;
		$buddyboss_thread_reply[ $object->ID ] = $object;
	}

	/**
	 * @since 2.4.0 bbPress (r4944)
	 */
	public function end_el( &$output = '', $object = false, $depth = 0, $args = array() ) {
	}
}