class-wp-bootstrap-mega-navwalker.php

<?php
/**
 * WP Bootstrap Mega Navwalker
 *
 * @package WP-Bootstrap-Mega-Navwalker
 */

/*
 * Class Name: WP_Bootstrap_Mega_Navwalker
 * Plugin Name: WP Bootstrap Mega Navwalker
 * Plugin URI:  https://github.com/wp-bootstrap/WP-Bootstrap-MegaMenu-Navwalker
 * Description: A custom WordPress nav walker class to implement the Bootstrap 4 navigation style in a custom theme using the WordPress built in menu manager.
 * Author: WP Bootstrap Team, @jaycbrf4
 * Version: 1.0.0
 * Author URI: https://github.com/wp-bootstrap
 * GitHub Plugin URI: https://github.com/wp-bootstrap/WP-Bootstrap-MegaMenu-Navwalker
 * GitHub Branch: master
 * License: GPL-3.0+
 * License URI: http://www.gnu.org/licenses/gpl-3.0.txt
*/

if ( ! class_exists( 'WP_Bootstrap_Mega_Navwalker' ) ) {
	/**
	 * WP_Bootstrap_Mega_Navwalker class.
	 *
	 * @extends Walker_Nav_Menu
	 */
	class WP_Bootstrap_Mega_Navwalker extends Walker_Nav_Menu {


		/**
		 * Start Level.
		 *
		 * @access public
		 * @param mixed &$output Output.
		 * @param int   $depth (default: 0) Depth.
		 * @param array $args (default: array()) Arguments.
		 * @return void
		 */
		public function start_lvl( &$output, $depth = 0, $args = array() ) {
			$indent  = str_repeat( "\t", $depth );
			$submenu = ( $depth > 0 ) ? ' sub-menu' : '';
			$output .= "\n$indent<ul class=\"dropdown-menu$submenu depth_$depth\">\n";
		}


		/**
		 * Start El.
		 *
		 * @access public
		 * @param mixed &$output Output.
		 * @param mixed $item Item.
		 * @param int   $depth (default: 0) Depth.
		 * @param array $args (default: array()) Arguments.
		 * @param int   $id (default: 0) ID.
		 * @return void
		 */
		public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
			$indent        = ( $depth ) ? str_repeat( "\t", $depth ) : '';
			$li_attributes = '';
			$class_names   = $value = '';
			$has_mega_menu = is_active_sidebar( 'mega-menu-item-' . $item->ID );

			$classes = empty( $item->classes ) ? array() : (array) $item->classes;

			// managing divider: add divider class to an element to get a divider before it.
			$divider_class_position = array_search( 'divider', $classes, true );

			if ( false !== $divider_class_position ) {
				$output .= "<li class=\"divider\"></li>\n";
				unset( $classes[ $divider_class_position ] );
			}

			$classes[] = ( $args->has_children || $has_mega_menu ) ? 'dropdown' : '';
			$classes[] = ( $item->current || $item->current_item_ancestor ) ? 'active' : '';
			$classes[] = 'nav-item-' . $item->ID;

			if ( $depth && $args->has_children ) {
				$classes[] = 'dropdown-submenu';
			}

			$class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );
			$class_names = ' class="nav-item ' . esc_attr( $class_names ) . '"';

			$id = apply_filters( 'nav_menu_item_id', 'nav-item-' . $item->ID, $item, $args );
			$id = strlen( $id ) ? ' id="' . esc_attr( $id ) . '"' : '';

			$output .= $indent . '<li' . $id . $value . $class_names . $li_attributes . '>';

			$attributes  = ! empty( $item->attr_title ) ? ' title="' . esc_attr( $item->attr_title ) . '"' : '';
			$attributes .= ! empty( $item->target ) ? ' target="' . esc_attr( $item->target ) . '"' : '';
			$attributes .= ! empty( $item->xfn ) ? ' rel="' . esc_attr( $item->xfn ) . '"' : '';
			$attributes .= ! empty( $item->url ) ? ' href="' . esc_attr( $item->url ) . '"' : '';
			$attributes .= ( $args->has_children || $has_mega_menu ) ? ' class="dropdown-toggle" data-toggle="dropdown"' : '';

			$item_output  = $args->before;
			$item_output .= '<a' . $attributes . '>';
			$item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
			$item_output .= ( ( 0 === $depth || 1 ) && ( $args->has_children || $has_mega_menu ) ) ? ' <b class="caret"></b></a>' : '</a>';
			$item_output .= $args->after;

			$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );

			if ( $has_mega_menu ) {
				$output .= "<ul id=\"mega-menu-{$item->ID}\" class=\"mega-menu-wrapper dropdown-menu depth_" . $depth . '">';
				ob_start();
				dynamic_sidebar( 'mega-menu-item-' . $item->ID );
				$dynamic_sidebar = ob_get_contents();
				ob_end_clean();
				$output .= $dynamic_sidebar;
				$output .= '</ul>';
			}
		}


		/**
		 * Display Element.
		 *
		 * @access public
		 * @param mixed $element Element.
		 * @param mixed &$children_elements Children Elements.
		 * @param mixed $max_depth Max Depth.
		 * @param int   $depth (default: 0) Depth.
		 * @param mixed $args Arguments.
		 * @param mixed &$output Output.
		 */
		public function display_element( $element, &$children_elements, $max_depth, $depth = 0, $args, &$output ) {

			if ( ! $element ) {
				return;
			}

			$id_field = $this->db_fields['id'];

			// Display this element.
			if ( is_array( $args[0] ) ) {
				$args[0]['has_children'] = ! empty( $children_elements[ $element->$id_field ] );
			} elseif ( is_object( $args[0] ) ) {
				$args[0]->has_children = ! empty( $children_elements[ $element->$id_field ] );
			}
			$cb_args = array_merge( array( &$output, $element, $depth ), $args );
			call_user_func_array( array( &$this, 'start_el' ), $cb_args );

			$id = $element->$id_field;

			// Descend only when the depth is right and there are childrens for this element.
			if ( ( 0 === $max_depth || $max_depth > $depth + 1 ) && isset( $children_elements[ $id ] ) ) {
				foreach ( $children_elements[ $id ] as $child ) {
					if ( ! isset( $newlevel ) ) {
						$newlevel = true;
						// Start the child delimiter.
						$cb_args = array_merge( array( &$output, $depth ), $args );
						call_user_func_array( array( &$this, 'start_lvl' ), $cb_args );
					}

					$this->display_element( $child, $children_elements, $max_depth, $depth + 1, $args, $output );
				}

				unset( $children_elements[ $id ] );
			}

			if ( isset( $newlevel ) && $newlevel ) {
				// End the child delimiter.
				$cb_args = array_merge( array( &$output, $depth ), $args );
				call_user_func_array( array( &$this, 'end_lvl' ), $cb_args );
			}

			// End this element.
			$cb_args = array_merge( array( &$output, $element, $depth ), $args );
			call_user_func_array( array( &$this, 'end_el' ), $cb_args );
		}
	}
}