<?php

/**

 * Navigation Menu functions

 *

 * @package WordPress

 * @subpackage Nav_Menus

 * @since 3.0.0

 */

/**

 * Returns a navigation menu object.

 *

 * @since 3.0.0

 *

 * @param int|string|WP_Term $menu Menu ID, slug, name, or object.

 * @return WP_Term|false False if $menu param isn't supplied or term does not exist, menu object if successful.

 */

function wp_get_nav_menu_object( $menu ) {

	$menu_obj = false;

	if ( is_object( $menu ) ) {

		$menu_obj = $menu;

	}

	if ( $menu && ! $menu_obj ) {

		$menu_obj = get_term( $menu, 'nav_menu' );

		if ( ! $menu_obj ) {

			$menu_obj = get_term_by( 'slug', $menu, 'nav_menu' );

		}

		if ( ! $menu_obj ) {

			$menu_obj = get_term_by( 'name', $menu, 'nav_menu' );

		}

	}

	if ( ! $menu_obj || is_wp_error( $menu_obj ) ) {

		$menu_obj = false;

	}

	/**

	 * Filters the nav_menu term retrieved for wp_get_nav_menu_object().

	 *

	 * @since 4.3.0

	 *

	 * @param WP_Term|false      $menu_obj Term from nav_menu taxonomy, or false if nothing had been found.

	 * @param int|string|WP_Term $menu     The menu ID, slug, name, or object passed to wp_get_nav_menu_object().

	 */

	return apply_filters( 'wp_get_nav_menu_object', $menu_obj, $menu );

}

/**

 * Check if the given ID is a navigation menu.

 *

 * Returns true if it is; false otherwise.

 *

 * @since 3.0.0

 *

 * @param int|string|WP_Term $menu Menu ID, slug, name, or object of menu to check.

 * @return bool Whether the menu exists.

 */

function is_nav_menu( $menu ) {

	if ( ! $menu ) {

		return false;

	}

	$menu_obj = wp_get_nav_menu_object( $menu );

	if (

		$menu_obj &&

		! is_wp_error( $menu_obj ) &&

		! empty( $menu_obj->taxonomy ) &&

		'nav_menu' == $menu_obj->taxonomy

	) {

		return true;

	}

	return false;

}

/**

 * Registers navigation menu locations for a theme.

 *

 * @since 3.0.0

 *

 * @global array $_wp_registered_nav_menus

 *

 * @param array $locations Associative array of menu location identifiers (like a slug) and descriptive text.

 */

function register_nav_menus( $locations = array() ) {

	global $_wp_registered_nav_menus;

	add_theme_support( 'menus' );

	$_wp_registered_nav_menus = array_merge( (array) $_wp_registered_nav_menus, $locations );

}

/**

 * Unregisters a navigation menu location for a theme.

 *

 * @since 3.1.0

 * @global array $_wp_registered_nav_menus

 *

 * @param string $location The menu location identifier.

 * @return bool True on success, false on failure.

 */

function unregister_nav_menu( $location ) {

	global $_wp_registered_nav_menus;

	if ( is_array( $_wp_registered_nav_menus ) && isset( $_wp_registered_nav_menus[ $location ] ) ) {

		unset( $_wp_registered_nav_menus[ $location ] );

		if ( empty( $_wp_registered_nav_menus ) ) {

			_remove_theme_support( 'menus' );

		}

		return true;

	}

	return false;

}

/**

 * Registers a navigation menu location for a theme.

 *

 * @since 3.0.0

 *

 * @param string $location    Menu location identifier, like a slug.

 * @param string $description Menu location descriptive text.

 */

function register_nav_menu( $location, $description ) {

	register_nav_menus( array( $location => $description ) );

}

/**

 * Retrieves all registered navigation menu locations in a theme.

 *

 * @since 3.0.0

 *

 * @global array $_wp_registered_nav_menus

 *

 * @return array Registered navigation menu locations. If none are registered, an empty array.

 */

function get_registered_nav_menus() {

	global $_wp_registered_nav_menus;

	if ( isset( $_wp_registered_nav_menus ) ) {

		return $_wp_registered_nav_menus;

	}

	return array();

}

/**

 * Retrieves all registered navigation menu locations and the menus assigned to them.

 *

 * @since 3.0.0

 *

 * @return array Registered navigation menu locations and the menus assigned them.

 *               If none are registered, an empty array.

 */

function get_nav_menu_locations() {

	$locations = get_theme_mod( 'nav_menu_locations' );

	return ( is_array( $locations ) ) ? $locations : array();

}

/**

 * Determines whether a registered nav menu location has a menu assigned to it.

 *

 * @since 3.0.0

 *

 * @param string $location Menu location identifier.

 * @return bool Whether location has a menu.

 */

function has_nav_menu( $location ) {

	$has_nav_menu = false;

	$registered_nav_menus = get_registered_nav_menus();

	if ( isset( $registered_nav_menus[ $location ] ) ) {

		$locations    = get_nav_menu_locations();

		$has_nav_menu = ! empty( $locations[ $location ] );

	}

	/**

	 * Filters whether a nav menu is assigned to the specified location.

	 *

	 * @since 4.3.0

	 *

	 * @param bool   $has_nav_menu Whether there is a menu assigned to a location.

	 * @param string $location     Menu location.

	 */

	return apply_filters( 'has_nav_menu', $has_nav_menu, $location );

}

/**

 * Returns the name of a navigation menu.

 *

 * @since 4.9.0

 *

 * @param string $location Menu location identifier.

 * @return string Menu name.

 */

function wp_get_nav_menu_name( $location ) {

	$menu_name = '';

	$locations = get_nav_menu_locations();

	if ( isset( $locations[ $location ] ) ) {

		$menu = wp_get_nav_menu_object( $locations[ $location ] );

		if ( $menu && $menu->name ) {

			$menu_name = $menu->name;

		}

	}

	/**

	 * Filters the navigation menu name being returned.

	 *

	 * @since 4.9.0

	 *

	 * @param string $menu_name Menu name.

	 * @param string $location  Menu location identifier.

	 */

	return apply_filters( 'wp_get_nav_menu_name', $menu_name, $location );

}

/**

 * Determines whether the given ID is a nav menu item.

 *

 * @since 3.0.0

 *

 * @param int $menu_item_id The ID of the potential nav menu item.

 * @return bool Whether the given ID is that of a nav menu item.

 */

function is_nav_menu_item( $menu_item_id = 0 ) {

	return ( ! is_wp_error( $menu_item_id ) && ( 'nav_menu_item' == get_post_type( $menu_item_id ) ) );

}

/**

 * Creates a navigation menu.

 *

 * Note that `$menu_name` is expected to be pre-slashed.

 *

 * @since 3.0.0

 *

 * @param string $menu_name Menu name.

 * @return int|WP_Error Menu ID on success, WP_Error object on failure.

 */

function wp_create_nav_menu( $menu_name ) {

	// expected_slashed ($menu_name)

	return wp_update_nav_menu_object( 0, array( 'menu-name' => $menu_name ) );

}

/**

 * Delete a Navigation Menu.

 *

 * @since 3.0.0

 *

 * @param int|string|WP_Term $menu Menu ID, slug, name, or object.

 * @return bool|WP_Error True on success, false or WP_Error object on failure.

 */

function wp_delete_nav_menu( $menu ) {

	$menu = wp_get_nav_menu_object( $menu );

	if ( ! $menu ) {

		return false;

	}

	$menu_objects = get_objects_in_term( $menu->term_id, 'nav_menu' );

	if ( ! empty( $menu_objects ) ) {

		foreach ( $menu_objects as $item ) {

			wp_delete_post( $item );

		}

	}

	$result = wp_delete_term( $menu->term_id, 'nav_menu' );

	// Remove this menu from any locations.

	$locations = get_nav_menu_locations();

	foreach ( $locations as $location => $menu_id ) {

		if ( $menu_id == $menu->term_id ) {

			$locations[ $location ] = 0;

		}

	}

	set_theme_mod( 'nav_menu_locations', $locations );

	if ( $result && ! is_wp_error( $result ) ) {

		/**

		 * Fires after a navigation menu has been successfully deleted.

		 *

		 * @since 3.0.0

		 *

		 * @param int $term_id ID of the deleted menu.

		 */

		do_action( 'wp_delete_nav_menu', $menu->term_id );

	}

	return $result;

}

/**

 * Save the properties of a menu or create a new menu with those properties.

 *

 * Note that `$menu_data` is expected to be pre-slashed.

 *

 * @since 3.0.0

 *

 * @param int   $menu_id   The ID of the menu or "0" to create a new menu.

 * @param array $menu_data The array of menu data.

 * @return int|WP_Error Menu ID on success, WP_Error object on failure.

 */

function wp_update_nav_menu_object( $menu_id = 0, $menu_data = array() ) {

	// expected_slashed ($menu_data)

	$menu_id = (int) $menu_id;

	$_menu = wp_get_nav_menu_object( $menu_id );

	$args = array(

		'description' => ( isset( $menu_data['description'] ) ? $menu_data['description'] : '' ),

		'name'        => ( isset( $menu_data['menu-name'] ) ? $menu_data['menu-name'] : '' ),

		'parent'      => ( isset( $menu_data['parent'] ) ? (int) $menu_data['parent'] : 0 ),

		'slug'        => null,

	);

	// double-check that we're not going to have one menu take the name of another

	$_possible_existing = get_term_by( 'name', $menu_data['menu-name'], 'nav_menu' );

	if (

		$_possible_existing &&

		! is_wp_error( $_possible_existing ) &&

		isset( $_possible_existing->term_id ) &&

		$_possible_existing->term_id != $menu_id

	) {

		return new WP_Error(

			'menu_exists',

			/* translators: %s: menu name */

			sprintf(

				__( 'The menu name %s conflicts with another menu name. Please try another.' ),

				'<strong>' . esc_html( $menu_data['menu-name'] ) . '</strong>'

			)

		);

	}

	// menu doesn't already exist, so create a new menu

	if ( ! $_menu || is_wp_error( $_menu ) ) {

		$menu_exists = get_term_by( 'name', $menu_data['menu-name'], 'nav_menu' );

		if ( $menu_exists ) {

			return new WP_Error(

				'menu_exists',

				/* translators: %s: menu name */

				sprintf(

					__( 'The menu name %s conflicts with another menu name. Please try another.' ),

					'<strong>' . esc_html( $menu_data['menu-name'] ) . '</strong>'

				)

			);

		}

		$_menu = wp_insert_term( $menu_data['menu-name'], 'nav_menu', $args );

		if ( is_wp_error( $_menu ) ) {

			return $_menu;

		}

		/**

		 * Fires after a navigation menu is successfully created.

		 *

		 * @since 3.0.0

		 *

		 * @param int   $term_id   ID of the new menu.

		 * @param array $menu_data An array of menu data.

		 */

		do_action( 'wp_create_nav_menu', $_menu['term_id'], $menu_data );

		return (int) $_menu['term_id'];

	}

	if ( ! $_menu || ! isset( $_menu->term_id ) ) {

		return 0;

	}

	$menu_id = (int) $_menu->term_id;

	$update_response = wp_update_term( $menu_id, 'nav_menu', $args );

	if ( is_wp_error( $update_response ) ) {

		return $update_response;

	}

	$menu_id = (int) $update_response['term_id'];

	/**

	 * Fires after a navigation menu has been successfully updated.

	 *

	 * @since 3.0.0

	 *

	 * @param int   $menu_id   ID of the updated menu.

	 * @param array $menu_data An array of menu data.

	 */

	do_action( 'wp_update_nav_menu', $menu_id, $menu_data );

	return $menu_id;

}

/**

 * Save the properties of a menu item or create a new one.

 *

 * The menu-item-title, menu-item-description, and menu-item-attr-title are expected

 * to be pre-slashed since they are passed directly into `wp_insert_post()`.

 *

 * @since 3.0.0

 *

 * @param int   $menu_id         The ID of the menu. Required. If "0", makes the menu item a draft orphan.

 * @param int   $menu_item_db_id The ID of the menu item. If "0", creates a new menu item.

 * @param array $menu_item_data  The menu item's data.

 * @return int|WP_Error The menu item's database ID or WP_Error object on failure.

 */

function wp_update_nav_menu_item( $menu_id = 0, $menu_item_db_id = 0, $menu_item_data = array() ) {

	$menu_id         = (int) $menu_id;

	$menu_item_db_id = (int) $menu_item_db_id;

	// make sure that we don't convert non-nav_menu_item objects into nav_menu_item objects

	if ( ! empty( $menu_item_db_id ) && ! is_nav_menu_item( $menu_item_db_id ) ) {

		return new WP_Error( 'update_nav_menu_item_failed', __( 'The given object ID is not that of a menu item.' ) );

	}

	$menu = wp_get_nav_menu_object( $menu_id );

	if ( ! $menu && 0 !== $menu_id ) {

		return new WP_Error( 'invalid_menu_id', __( 'Invalid menu ID.' ) );

	}

	if ( is_wp_error( $menu ) ) {

		return $menu;