<?php

/**
 * Class Name: activello_wp_bootstrap_navwalker
 * GitHub URI: https://github.com/twittem/wp-bootstrap-navwalker
 * Description: A custom WordPress nav walker class to implement the Bootstrap 3 navigation style in a custom theme using the WordPress built in menu manager.
 * Version: 2.0.4
 * Author: Edward McIntyre - @twittem
 * License: GPL-2.0+
 * License URI: http://www.gnu.org/licenses/gpl-2.0.txt
 */

class Activello_Wp_Bootstrap_Navwalker extends Walker_Nav_Menu {

		/**
		 * @see Walker::start_lvl()
		 * @since 3.0.0
		 *
		 * @param string $output Passed by reference. Used to append additional content.
		 * @param int $depth Depth of page. Used for padding.
		 */
	public function start_lvl( &$output, $depth = 0, $args = array() ) {
		$indent = str_repeat( "\t", $depth );
		$output .= "\n$indent<ul role=\"menu\" class=\" dropdown-menu\">\n";
	}

		/**
		 * @see Walker::start_el()
		 * @since 3.0.0
		 *
		 * @param string $output Passed by reference. Used to append additional content.
		 * @param object $item Menu item data object.
		 * @param int $depth Depth of menu item. Used for padding.
		 * @param int $current_page Menu item ID.
		 * @param object $args
		 */
	public function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
		$indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

		/**
				 * Dividers, Headers or Disabled
				 * =============================
				 * Determine whether the item is a Divider, Header, Disabled or regular
				 * menu item. To prevent errors we use the strcasecmp() function to so a
				 * comparison that is not case sensitive. The strcasecmp() function returns
				 * a 0 if the strings are equal.
				 */
		if ( 0 == strcasecmp( $item->attr_title, 'divider' ) && 1 === $depth ) {
			$output .= $indent . '<li role="presentation" class="divider">';
		} elseif ( 0 == strcasecmp( $item->title, 'divider' ) && 1 === $depth ) {
			$output .= $indent . '<li role="presentation" class="divider">';
		} elseif ( 0 == strcasecmp( $item->attr_title, 'dropdown-header' ) && 1 === $depth ) {
			$output .= $indent . '<li role="presentation" class="dropdown-header">' . esc_attr( $item->title );
		} elseif ( 0 == strcasecmp( $item->attr_title, 'disabled' ) ) {
			$output .= $indent . '<li role="presentation" class="disabled"><a href="#">' . esc_attr( $item->title ) . '</a>';
		} else {
			$class_names = '';
			$value = '';
			$classes = empty( $item->classes ) ? array() : (array) $item->classes;
			$classes[] = 'menu-item-' . $item->ID;

			$class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );

			// if ( $args->has_children )
			//         $class_names .= ' dropdown';

			if ( in_array( 'current-menu-item', $classes ) ) {
					$class_names .= ' active';
			}

			$class_names = $class_names ? ' class="' . esc_attr( $class_names ) . '"' : '';

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

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

			$atts = array();
			$atts['title']  = ! empty( $item->title )        ? $item->title        : '';
			$atts['target'] = ! empty( $item->target )        ? $item->target        : '';
			$atts['rel']    = ! empty( $item->xfn )                ? $item->xfn        : '';

			// If item has_children add atts to a.
			if ( 0 === $args->has_children && $depth ) {
				$atts['href']                   = ! empty( $item->url ) ? $item->url : '';
				;
				// $atts['data-toggle']        = 'dropdown';
				$atts['class']                        = 'dropdown-toggle';
			} else {
				$atts['href'] = ! empty( $item->url ) ? $item->url : '';
			}

			$atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args );

			$attributes = '';
			foreach ( $atts as $attr => $value ) {
				if ( ! empty( $value ) ) {
					$value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
					$attributes .= ' ' . $attr . '="' . $value . '"';
				}
			}

			$item_output = $args->before;

			/*
			 * Glyphicons
			 * ===========
			 * Since the the menu item is NOT a Divider or Header we check the see
			 * if there is a value in the attr_title property. If the attr_title
			 * property is NOT null we apply it as the class name for the glyphicon.
			 */
			if ( ! empty( $item->attr_title ) ) {
					$item_output .= '<a' . $attributes . '><span class="glyphicon ' . esc_attr( $item->attr_title ) . '"></span>&nbsp;';
			} else {                  $item_output .= '<a' . $attributes . '>';
			}

			$item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
			$item_output .= ( $args->has_children ) ? ' </a><span class="activello-dropdown"></span>' : '</a>';
			$item_output .= $args->after;

			$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
		}// End if().
	}

		/**
		 * Traverse elements to create list from elements.
		 *
		 * Display one element if the element doesn't have any children otherwise,
		 * display the element and its children. Will only traverse up to the max
		 * depth and no ignore elements under that depth.
		 *
		 * This method shouldn't be called directly, use the walk() method instead.
		 *
		 * @see Walker::start_el()
		 * @since 2.5.0
		 *
		 * @param object $element Data object
		 * @param array $children_elements List of elements to continue traversing.
		 * @param int $max_depth Max depth to traverse.
		 * @param int $depth Depth of current element.
		 * @param array $args
		 * @param string $output Passed by reference. Used to append additional content.
		 * @return null Null on failure with no changes to parameters.
		 */
	public function display_element( $element, &$children_elements, $max_depth, $depth, $args, &$output ) {
		if ( ! $element ) {
			return;
		}

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

		// Display this element.
		if ( is_object( $args[0] ) ) {
			$args[0]->has_children = ! empty( $children_elements[ $element->$id_field ] );
		}

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

		/**
		 * Menu Fallback
		 * =============
		 * If this function is assigned to the wp_nav_menu's fallback_cb variable
		 * and a manu has not been assigned to the theme location in the WordPress
		 * menu manager the function with display nothing to a non-logged in user,
		 * and will add a link to the WordPress menu manager if logged in as an admin.
		 *
		 * @param array $args passed from the wp_nav_menu function.
		 *
		 */
	public static function fallback( $args ) {
		$fb_output = null;

		if ( $args['container'] ) {
			$fb_output = '<' . $args['container'];

			if ( $args['container_id'] ) {
					$fb_output .= ' id="' . $args['container_id'] . '"';
			}

			if ( $args['container_class'] ) {
					$fb_output .= ' class="' . $args['container_class'] . '"';
			}

			$fb_output .= '>';
		}

		$fb_output .= '<ul';

		if ( $args['menu_id'] ) {
				$fb_output .= ' id="' . $args['menu_id'] . '"';
		}

		if ( $args['menu_class'] ) {
				$fb_output .= ' class="' . $args['menu_class'] . '"';
		}

		$fb_output .= '>';
		$fb_output .= wp_list_pages( array(
			'depth' => 1, //number of tiers, 0 for unlimited
			'exclude' => '', //comma seperated IDs of pages you want to exclude
			'title_li' => '', //must override it to empty string so that it does not break our nav
			'sort_column' => 'post_title', //see documentation for other possibilites
			'sort_order' => 'ASC', //ASCending or DESCending
			'echo' => false,
		));
		$fb_output .= '</ul>';

		if ( $args['container'] ) {
				$fb_output .= '</' . $args['container'] . '>';
		}

		echo $fb_output;
	}
}
