<?php

/**

 *

 * @package WordPress

 * @subpackage Nav_Menus

 * @since 3.0.0

 */

/**

 * Displays a navigation menu.

 *

 * @since 3.0.0

 *

 * @param array $args {

 *     Optional. Array of nav menu arguments.

 *

 * }

 */

function wp_nav_menu( $args = array() ) {

	static $menu_id_slugs = array();

	$defaults = array( 'menu' => '', 'container' => 'div', 'container_class' => '', 'container_id' => '', 'menu_class' => 'menu', 'menu_id' => '',

	'depth' => 0, 'walker' => '', 'theme_location' => '' );

	$args = wp_parse_args( $args, $defaults );

	/**

	 *

	 * @since 3.0.0

	 *

	 * @see wp_nav_menu()

	 *

	 * @param array $args Array of wp_nav_menu() arguments.

	 */

	$args = apply_filters( 'wp_nav_menu_args', $args );

	$args = (object) $args;

	/**

	 *

	 * Returning a non-null value to the filter will short-circuit

	 * wp_nav_menu(), echoing that value if $args->echo is true,

	 * returning that value otherwise.

	 *

	 * @since 3.9.0

	 *

	 * @see wp_nav_menu()

	 *

	 * @param string|null $output Nav menu output to short-circuit with. Default null.

	 */

	$nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );

	if ( null !== $nav_menu ) {

		if ( $args->echo ) {

			echo $nav_menu;

			return;

		}

		return $nav_menu;

	}

	// Get the nav menu based on the requested menu

	$menu = wp_get_nav_menu_object( $args->menu );

	// Get the nav menu based on the theme_location

	if ( ! $menu && $args->theme_location && ( $locations = get_nav_menu_locations() ) && isset( $locations[ $args->theme_location ] ) )

		$menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );

	// get the first menu that has items if we still can't find a menu

	if ( ! $menu && !$args->theme_location ) {

		$menus = wp_get_nav_menus();

		foreach ( $menus as $menu_maybe ) {

			if ( $menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) ) ) {

				$menu = $menu_maybe;

				break;

			}

		}

	}

	// If the menu exists, get its items.

	if ( $menu && ! is_wp_error($menu) && !isset($menu_items) )

		$menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );

	/*

	 * If no menu was found:

	 *  - Fall back (if one was specified), or bail.

	 *

	 * If no menu items were found:

	 *  - Fall back, but only if no theme location was specified.

	 *  - Otherwise, bail.

	 */

	if ( ( !$menu || is_wp_error($menu) || ( isset($menu_items) && empty($menu_items) && !$args->theme_location ) )

			return call_user_func( $args->fallback_cb, (array) $args );

	if ( ! $menu || is_wp_error( $menu ) )

		return false;

	$nav_menu = $items = '';

	$show_container = false;

	if ( $args->container ) {

		/**

		 *

		 * @since 3.0.0

		 *

		 * @param array $tags The acceptable HTML tags for use as menu containers.

		 *                    Default is array containing 'div' and 'nav'.

		 */

		$allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );

			$show_container = true;

			$class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-'. $menu->slug .'-container"';

			$id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';

			$nav_menu .= '<'. $args->container . $id . $class . '>';

		}

	}

	// Set up the $menu_item variables

	_wp_menu_item_classes_by_context( $menu_items );

	$sorted_menu_items = $menu_items_with_children = array();

	foreach ( (array) $menu_items as $menu_item ) {

		$sorted_menu_items[ $menu_item->menu_order ] = $menu_item;

		if ( $menu_item->menu_item_parent )

			$menu_items_with_children[ $menu_item->menu_item_parent ] = true;

	}

	// Add the menu-item-has-children class where applicable

	if ( $menu_items_with_children ) {

		foreach ( $sorted_menu_items as &$menu_item ) {

			if ( isset( $menu_items_with_children[ $menu_item->ID ] ) )

				$menu_item->classes[] = 'menu-item-has-children';

		}

	}

	unset( $menu_items, $menu_item );

	/**

	 *

	 * @since 3.1.0

	 *

	 */

	$sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );

	$items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );

	unset($sorted_menu_items);

	// Attributes

	if ( ! empty( $args->menu_id ) ) {

		$wrap_id = $args->menu_id;

	} else {

		$wrap_id = 'menu-' . $menu->slug;

		while ( in_array( $wrap_id, $menu_id_slugs ) ) {

			if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) )

				$wrap_id = preg_replace('#-(\d+)$#', '-' . ++$matches[1], $wrap_id );

			else

				$wrap_id = $wrap_id . '-1';

		}

	}

	$menu_id_slugs[] = $wrap_id;

	$wrap_class = $args->menu_class ? $args->menu_class : '';

	/**

	 *

	 * @since 3.0.0

	 *

	 * @see wp_nav_menu()

	 *

	 */

	$items = apply_filters( 'wp_nav_menu_items', $items, $args );

	/**

	 *

	 * @since 3.0.0

	 *

	 * @see wp_nav_menu()

	 *

	 */

	$items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );

	// Don't print any markup if there are no items at this point.

	if ( empty( $items ) )

		return false;

	$nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );

	unset( $items );

	if ( $show_container )

		$nav_menu .= '</' . $args->container . '>';

	/**

	 *

	 * @since 3.0.0

	 *

	 * @see wp_nav_menu()

	 *

	 */

	$nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );

	if ( $args->echo )

		echo $nav_menu;

	else

		return $nav_menu;

}

/**

 * Add the class property classes for the current context, if applicable.

 *

 * @access private

 * @since 3.0.0

 *

 * @param array $menu_items The current menu item objects to which to add the class property information.

 */

function _wp_menu_item_classes_by_context( &$menu_items ) {

	global $wp_query, $wp_rewrite;

	$queried_object = $wp_query->get_queried_object();

	$queried_object_id = (int) $wp_query->queried_object_id;

	$active_object = '';

	$active_ancestor_item_ids = array();

	$active_parent_item_ids = array();

	$active_parent_object_ids = array();

	$possible_taxonomy_ancestors = array();

	$possible_object_parents = array();

	$home_page_id = (int) get_option( 'page_for_posts' );

	if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {

		foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {

			if ( is_taxonomy_hierarchical( $taxonomy ) ) {

				$term_hierarchy = _get_term_hierarchy( $taxonomy );

				$terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );

				if ( is_array( $terms ) ) {

					$possible_object_parents = array_merge( $possible_object_parents, $terms );

					$term_to_ancestor = array();

					foreach ( (array) $term_hierarchy as $anc => $descs ) {

						foreach ( (array) $descs as $desc )

							$term_to_ancestor[ $desc ] = $anc;

					}

					foreach ( $terms as $desc ) {

						do {

							$possible_taxonomy_ancestors[ $taxonomy ][] = $desc;

							if ( isset( $term_to_ancestor[ $desc ] ) ) {

								$_desc = $term_to_ancestor[ $desc ];

								unset( $term_to_ancestor[ $desc ] );

								$desc = $_desc;

							} else {

								$desc = 0;

							}

						} while ( ! empty( $desc ) );

					}

				}

			}

		}

	} elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {

		$term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );

		$term_to_ancestor = array();

		foreach ( (array) $term_hierarchy as $anc => $descs ) {

			foreach ( (array) $descs as $desc )

				$term_to_ancestor[ $desc ] = $anc;

		}

		$desc = $queried_object->term_id;

		do {

			$possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;

			if ( isset( $term_to_ancestor[ $desc ] ) ) {

				$_desc = $term_to_ancestor[ $desc ];

				unset( $term_to_ancestor[ $desc ] );

				$desc = $_desc;

			} else {

				$desc = 0;

			}

		} while ( ! empty( $desc ) );

	}

	$possible_object_parents = array_filter( $possible_object_parents );

	$front_page_url = home_url();

	foreach ( (array) $menu_items as $key => $menu_item ) {

		$menu_items[$key]->current = false;

		$classes = (array) $menu_item->classes;

		$classes[] = 'menu-item';

		$classes[] = 'menu-item-type-' . $menu_item->type;

		$classes[] = 'menu-item-object-' . $menu_item->object;

		// if the menu item corresponds to a taxonomy term for the currently-queried non-hierarchical post object

		if ( $wp_query->is_singular && 'taxonomy' == $menu_item->type && in_array( $menu_item->object_id, $possible_object_parents ) ) {

			$active_parent_object_ids[] = (int) $menu_item->object_id;

			$active_parent_item_ids[] = (int) $menu_item->db_id;

			$active_object = $queried_object->post_type;

		// if the menu item corresponds to the currently-queried post or taxonomy object

		} elseif (

			$menu_item->object_id == $queried_object_id &&

			(

				( ! empty( $home_page_id ) && 'post_type' == $menu_item->type && $wp_query->is_home && $home_page_id == $menu_item->object_id ) ||

				( 'post_type' == $menu_item->type && $wp_query->is_singular ) ||

				( 'taxonomy' == $menu_item->type && ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax ) && $queried_object->taxonomy == $menu_item->object )

			)

		) {

			$classes[] = 'current-menu-item';

			$menu_items[$key]->current = true;

			$_anc_id = (int) $menu_item->db_id;

			while(

				( $_anc_id = get_post_meta( $_anc_id, '_menu_item_menu_item_parent', true ) ) &&

				! in_array( $_anc_id, $active_ancestor_item_ids )

			) {

				$active_ancestor_item_ids[] = $_anc_id;

			}

			if ( 'post_type' == $menu_item->type && 'page' == $menu_item->object ) {

				// Back compat classes for pages to match wp_page_menu()

				$classes[] = 'page_item';

				$classes[] = 'page-item-' . $menu_item->object_id;

				$classes[] = 'current_page_item';

			}

			$active_parent_item_ids[] = (int) $menu_item->menu_item_parent;

			$active_parent_object_ids[] = (int) $menu_item->post_parent;

			$active_object = $menu_item->object;