ault null.
 * @param string                $username Username for authentication.
 * @param string                $password Password for authentication.
 * @return WP_User|WP_Error WP_User on success, WP_Error on failure.
 */
function wp_authenticate_username_password( $user, $username, $password ) {
	if ( $user instanceof WP_User ) {
		return $user;
	}

	if ( empty( $username ) || empty( $password ) ) {
		if ( is_wp_error( $user ) ) {
			return $user;
		}

		$error = new WP_Error();

		if ( empty( $username ) ) {
			$error->add( 'empty_username', __( '<strong>Error:</strong> The username field is empty.' ) );
		}

		if ( empty( $password ) ) {
			$error->add( 'empty_password', __( '<strong>Error:</strong> The password field is empty.' ) );
		}

		return $error;
	}

	$user = get_user_by( 'login', $username );

	if ( ! $user ) {
		return new WP_Error(
			'invalid_username',
			sprintf(
				/* translators: %s: User name. */
				__( '<strong>Error:</strong> The username <strong>%s</strong> is not registered on this site. If you are unsure of your username, try your email address instead.' ),
				$username
			)
		);
	}

	/**
	 * Filters whether the given user can be authenticated with the provided password.
	 *
	 * @since 2.5.0
	 *
	 * @param WP_User|WP_Error $user     WP_User or WP_Error object if a previous
	 *                                   callback failed authentication.
	 * @param string           $password Password to check against the user.
	 */
	$user = apply_filters( 'wp_authenticate_user', $user, $password );
	if ( is_wp_error( $user ) ) {
		return $user;
	}

	if ( ! wp_check_password( $password, $user->user_pass, $user->ID ) ) {
		return new WP_Error(
			'incorrect_password',
			sprintf(
				/* translators: %s: User name. */
				__( '<strong>Error:</strong> The password you entered for the username %s is incorrect.' ),
				'<strong>' . $username . '</strong>'
			) .
			' <a href="' . wp_lostpassword_url() . '">' .
			__( 'Lost your password?' ) .
			'</a>'
		);
	}

	return $user;
}

/**
 * Authenticates a user using the email and password.
 *
 * @since 4.5.0
 *
 * @param WP_User|WP_Error|null $user     WP_User or WP_Error object if a previous
 *                                        callback failed authentication.
 * @param string                $email    Email address for authentication.
 * @param string                $password Password for authentication.
 * @return WP_User|WP_Error WP_User on success, WP_Error on failure.
 */
function wp_authenticate_email_password( $user, $email, $password ) {
	if ( $user instanceof WP_User ) {
		return $user;
	}

	if ( empty( $email ) || empty( $password ) ) {
		if ( is_wp_error( $user ) ) {
			return $user;
		}

		$error = new WP_Error();

		if ( empty( $email ) ) {
			// Uses 'empty_username' for back-compat with wp_signon().
			$error->add( 'empty_username', __( '<strong>Error:</strong> The email field is empty.' ) );
		}

		if ( empty( $password ) ) {
			$error->add( 'empty_password', __( '<strong>Error:</strong> The password field is empty.' ) );
		}

		return $error;
	}

	if ( ! is_email( $email ) ) {
		return $user;
	}

	$user = get_user_by( 'email', $email );

	if ( ! $user ) {
		return new WP_Error(
			'invalid_email',
			__( 'Unknown email address. Check again or try your username.' )
		);
	}

	/** This filter is documented in wp-includes/user.php */
	$user = apply_filters( 'wp_authenticate_user', $user, $password );

	if ( is_wp_error( $user ) ) {
		return $user;
	}

	if ( ! wp_check_password( $password, $user->user_pass, $user->ID ) ) {
		return new WP_Error(
			'incorrect_password',
			sprintf(
				/* translators: %s: Email address. */
				__( '<strong>Error:</strong> The password you entered for the email address %s is incorrect.' ),
				'<strong>' . $email . '</strong>'
			) .
			' <a href="' . wp_lostpassword_url() . '">' .
			__( 'Lost your password?' ) .
			'</a>'
		);
	}

	return $user;
}

/**
 * Authenticates the user using the WordPress auth cookie.
 *
 * @since 2.8.0
 *
 * @global string $auth_secure_cookie
 *
 * @param WP_User|WP_Error|null $user     WP_User or WP_Error object from a previous callback. Default null.
 * @param string                $username Username. If not empty, cancels the cookie authentication.
 * @param string                $password Password. If not empty, cancels the cookie authentication.
 * @return WP_User|WP_Error WP_User on success, WP_Error on failure.
 */
function wp_authenticate_cookie( $user, $username, $password ) {
	if ( $user instanceof WP_User ) {
		return $user;
	}

	if ( empty( $username ) && empty( $password ) ) {
		$user_id = wp_validate_auth_cookie();
		if ( $user_id ) {
			return new WP_User( $user_id );
		}

		global $auth_secure_cookie;

		if ( $auth_secure_cookie ) {
			$auth_cookie = SECURE_AUTH_COOKIE;
		} else {
			$auth_cookie = AUTH_COOKIE;
		}

		if ( ! empty( $_COOKIE[ $auth_cookie ] ) ) {
			return new WP_Error( 'expired_session', __( 'Please log in again.' ) );
		}

		// If the cookie is not set, be silent.
	}

	return $user;
}

/**
 * Authenticates the user using an application password.
 *
 * @since 5.6.0
 *
 * @param WP_User|WP_Error|null $input_user WP_User or WP_Error object if a previous
 *                                          callback failed authentication.
 * @param string                $username   Username for authentication.
 * @param string                $password   Password for authentication.
 * @return WP_User|WP_Error|null WP_User on success, WP_Error on failure, null if
 *                               null is passed in and this isn't an API request.
 */
function wp_authenticate_application_password( $input_user, $username, $password ) {
	if ( $input_user instanceof WP_User ) {
		return $input_user;
	}

	if ( ! WP_Application_Passwords::is_in_use() ) {
		return $input_user;
	}

	$is_api_request = ( ( defined( 'XMLRPC_REQUEST' ) && XMLRPC_REQUEST ) || ( defined( 'REST_REQUEST' ) && REST_REQUEST ) );

	/**
	 * Filters whether this is an API request that Application Passwords can be used on.
	 *
	 * By default, Application Passwords is available for the REST API and XML-RPC.
	 *
	 * @since 5.6.0
	 *
	 * @param bool $is_api_request If this is an acceptable API request.
	 */
	$is_api_request = apply_filters( 'application_password_is_api_request', $is_api_request );

	if ( ! $is_api_request ) {
		return $input_user;
	}

	$error = null;
	$user  = get_user_by( 'login', $username );

	if ( ! $user && is_email( $username ) ) {
		$user = get_user_by( 'email', $username );
	}

	// If the login name is invalid, short circuit.
	if ( ! $user ) {
		if ( is_email( $username ) ) {
			$error = new WP_Error(
				'invalid_email',
				__( '<strong>Error:</strong> Unknown email address. Check again or try your username.' )
			);
		} else {
			$error = new WP_Error(
				'invalid_username',
				__( '<strong>Error:</strong> Unknown username. Check again or try your email address.' )
			);
		}
	} elseif ( ! wp_is_application_passwords_available() ) {
		$error = new WP_Error(
			'application_passwords_disabled',
			__( 'Application passwords are not available.' )
		);
	} elseif ( ! wp_is_application_passwords_available_for_user( $user ) ) {
		$error = new WP_Error(
			'application_passwords_disabled_for_user',
			__( 'Application passwords are not available for your account. Please contact the site administrator for assistance.' )
		);
	}

	if ( $error ) {
		/**
		 * Fires when an application password failed to authenticate the user.
		 *
		 * @since 5.6.0
		 *
		 * @param WP_Error $error The authentication error.
		 */
		do_action( 'application_password_failed_authentication', $error );

		return $error;
	}

	/*
	 * Strips out anything non-alphanumeric. This is so passwords can be used with
	 * or without spaces to indicate the groupings for readability.
	 *
	 * Generated application passwords are exclusively alphanumeric.
	 */
	$password = preg_replace( '/[^a-z\d]/i', '', $password );

	$hashed_passwords = WP_Application_Passwords::get_user_application_passwords( $user->ID );

	foreach ( $hashed_passwords as $key => $item ) {
		if ( ! wp_check_password( $password, $item['password'], $user->ID ) ) {
			continue;
		}

		$error = new WP_Error();

		/**
		 * Fires when an application password has been successfully checked as valid.
		 *
		 * This allows for plugins to add additional constraints to prevent an application password from being used.
		 *
		 * @since 5.6.0
		 *
		 * @param WP_Error $error    The error object.
		 * @param WP_User  $user     The user authenticating.
		 * @param array    $item     The details about the application password.
		 * @param string   $password The raw supplied password.
		 */
		do_action( 'wp_authenticate_application_password_errors', $error, $user, $item, $password );

		if ( is_wp_error( $error ) && $error->has_errors() ) {
			/** This action is documented in wp-includes/user.php */
			do_action( 'application_password_failed_authentication', $error );

			return $error;
		}

		WP_Application_Passwords::record_application_password_usage( $user->ID, $item['uuid'] );

		/**
		 * Fires after an application password was used for authentication.
		 *
		 * @since 5.6.0
		 *
		 * @param WP_User $user The user who was authenticated.
		 * @param array   $item The application password used.
		 */
		do_action( 'application_password_did_authenticate', $user, $item );

		return $user;
	}

	$error = new WP_Error(
		'incorrect_password',
		__( 'The provided password is an invalid application password.' )
	);

	/** This action is documented in wp-includes/user.php */
	do_action( 'application_password_failed_authentication', $error );

	return $error;
}

/**
 * Validates the application password credentials passed via Basic Authentication.
 *
 * @since 5.6.0
 *
 * @param int|false $input_user User ID if one has been determined, false otherwise.
 * @return int|false The authenticated user ID if successful, false otherwise.
 */
function wp_validate_application_password( $input_user ) {
	// Don't authenticate twice.
	if ( ! empty( $input_user ) ) {
		return $input_user;
	}

	if ( ! wp_is_application_passwords_available() ) {
		return $input_user;
	}

	// Both $_SERVER['PHP_AUTH_USER'] and $_SERVER['PHP_AUTH_PW'] must be set in order to attempt authentication.
	if ( ! isset( $_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW'] ) ) {
		return $input_user;
	}

	$authenticated = wp_authenticate_application_password( null, $_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW'] );

	if ( $authenticated instanceof WP_User ) {
		return $authenticated->ID;
	}

	// If it wasn't a user what got returned, just pass on what we had received originally.
	return $input_user;
}

/**
 * For Multisite blogs, checks if the authenticated user has been marked as a
 * spammer, or if the user's primary blog has been marked as spam.
 *
 * @since 3.7.0
 *
 * @param WP_User|WP_Error|null $user WP_User or WP_Error object from a previous callback. Default null.
 * @return WP_User|WP_Error WP_User on success, WP_Error if the user is considered a spammer.
 */
function wp_authenticate_spam_check( $user ) {
	if ( $user instanceof WP_User && is_multisite() ) {
		/**
		 * Filters whether the user has been marked as a spammer.
		 *
		 * @since 3.7.0
		 *
		 * @param bool    $spammed Whether the user is considered a spammer.
		 * @param WP_User $user    User to check against.
		 */
		$spammed = apply_filters( 'check_is_user_spammed', is_user_spammy( $user ), $user );

		if ( $spammed ) {
			return new WP_Error( 'spammer_account', __( '<strong>Error:</strong> Your account has been marked as a spammer.' ) );
		}
	}
	return $user;
}

/**
 * Validates the logged-in cookie.
 *
 * Checks the logged-in cookie if the previous auth cookie could not be
 * validated and parsed.
 *
 * This is a callback for the {@see 'determine_current_user'} filter, rather than API.
 *
 * @since 3.9.0
 *
 * @param int|false $user_id The user ID (or false) as received from
 *                           the `determine_current_user` filter.
 * @return int|false User ID if validated, false otherwise. If a user ID from
 *                   an earlier filter callback is received, that value is returned.
 */
function wp_validate_logged_in_cookie( $user_id ) {
	if ( $user_id ) {
		return $user_id;
	}

	if ( is_blog_admin() || is_network_admin() || empty( $_COOKIE[ LOGGED_IN_COOKIE ] ) ) {
		return false;
	}

	return wp_validate_auth_cookie( $_COOKIE[ LOGGED_IN_COOKIE ], 'logged_in' );
}

/**
 * Gets the number of posts a user has written.
 *
 * @since 3.0.0
 * @since 4.1.0 Added `$post_type` argument.
 * @since 4.3.0 Added `$public_only` argument. Added the ability to pass an array
 *              of post types to `$post_type`.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int          $userid      User ID.
 * @param array|string $post_type   Optional. Single post type or array of post types to count the number of posts for. Default 'post'.
 * @param bool         $public_only Optional. Whether to only return counts for public posts. Default false.
 * @return string Number of posts the user has written in this post type.
 */
function count_user_posts( $userid, $post_type = 'post', $public_only = false ) {
	global $wpdb;

	$where = get_posts_by_author_sql( $post_type, true, $userid, $public_only );

	$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->posts $where" );

	/**
	 * Filters the number of posts a user has written.
	 *
	 * @since 2.7.0
	 * @since 4.1.0 Added `$post_type` argument.
	 * @since 4.3.1 Added `$public_only` argument.
	 *
	 * @param int          $count       The user's post count.
	 * @param int          $userid      User ID.
	 * @param string|array $post_type   Single post type or array of post types to count the number of posts for.
	 * @param bool         $public_only Whether to limit counted posts to public posts.
	 */
	return apply_filters( 'get_usernumposts', $count, $userid, $post_type, $public_only );
}

/**
 * Gets the number of posts written by a list of users.
 *
 * @since 3.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int[]           $users       Array of user IDs.
 * @param string|string[] $post_type   Optional. Single post type or array of post types to check. Defaults to 'post'.
 * @param bool            $public_only Optional. Only return counts for public posts.  Defaults to false.
 * @return string[] Amount of posts each user has written, as strings, keyed by user ID.
 */
function count_many_users_posts( $users, $post_type = 'post', $public_only = false ) {
	global $wpdb;

	$count = array();
	if ( empty( $users ) || ! is_array( $users ) ) {
		return $count;
	}

	$userlist = implode( ',', array_map( 'absint', $users ) );
	$where    = get_posts_by_author_sql( $post_type, true, null, $public_only );

	$result = $wpdb->get_results( "SELECT post_author, COUNT(*) FROM $wpdb->posts $where AND post_author IN ($userlist) GROUP BY post_author", ARRAY_N );
	foreach ( $result as $row ) {
		$count[ $row[0] ] = $row[1];
	}

	foreach ( $users as $id ) {
		if ( ! isset( $count[ $id ] ) ) {
			$count[ $id ] = 0;
		}
	}

	return $count;
}

//
// User option functions.
//

/**
 * Gets the current user's ID.
 *
 * @since MU (3.0.0)
 *
 * @return int The current user's ID, or 0 if no user is logged in.
 */
function get_current_user_id() {
	if ( ! function_exists( 'wp_get_current_user' ) ) {
		return 0;
	}
	$user = wp_get_current_user();
	return ( isset( $user->ID ) ? (int) $user->ID : 0 );
}

/**
 * Retrieves user option that can be either per Site or per Network.
 *
 * If the user ID is not given, then the current user will be used instead. If
 * the user ID is given, then the user data will be retrieved. The filter for
 * the result, will also pass the original option name and finally the user data
 * object as the third parameter.
 *
 * The option will first check for the per site name and then the per Network name.
 *
 * @since 2.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $option     User option name.
 * @param int    $user       Optional. User ID.
 * @param string $deprecated Use get_option() to check for an option in the options table.
 * @return mixed User option value on success, false on failure.
 */
function get_user_option( $option, $user = 0, $deprecated = '' ) {
	global $wpdb;

	if ( ! empty( $deprecated ) ) {
		_deprecated_argument( __FUNCTION__, '3.0.0' );
	}

	if ( empty( $user ) ) {
		$user = get_current_user_id();
	}

	$user = get_userdata( $user );
	if ( ! $user ) {
		return false;
	}

	$prefix = $wpdb->get_blog_prefix();
	if ( $user->has_prop( $prefix . $option ) ) { // Blog-specific.
		$result = $user->get( $prefix . $option );
	} elseif ( $user->has_prop( $option ) ) { // User-specific and cross-blog.
		$result = $user->get( $option );
	} else {
		$result = false;
	}

	/**
	 * Filters a specific user option value.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the user option name.
	 *
	 * @since 2.5.0
	 *
	 * @param mixed   $result Value for the user's option.
	 * @param string  $option Name of the option being retrieved.
	 * @param WP_User $user   WP_User object of the user whose option is being retrieved.
	 */
	return apply_filters( "get_user_option_{$option}", $result, $option, $user );
}

/**
 * Updates user option with global blog capability.
 *
 * User options are just like user metadata except that they have support for
 * global blog options. If the 'is_global' parameter is false, which it is by default,
 * it will prepend the WordPress table prefix to the option name.
 *
 * Deletes the user option if $newvalue is empty.
 *
 * @since 2.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $user_id     User ID.
 * @param string $option_name User option name.
 * @param mixed  $newvalue    User option value.
 * @param bool   $is_global   Optional. Whether option name is global or blog specific.
 *                            Default false (blog specific).
 * @return int|bool User meta ID if the option didn't exist, true on successful update,
 *                  false on failure.
 */
function update_user_option( $user_id, $option_name, $newvalue, $is_global = false ) {
	global $wpdb;

	if ( ! $is_global ) {
		$option_name = $wpdb->get_blog_prefix() . $option_name;
	}

	return update_user_meta( $user_id, $option_name, $newvalue );
}

/**
 * Deletes user option with global blog capability.
 *
 * User options are just like user metadata except that they have support for
 * global blog options. If the 'is_global' parameter is false, which it is by default,
 * it will prepend the WordPress table prefix to the option name.
 *
 * @since 3.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $user_id     User ID
 * @param string $option_name User option name.
 * @param bool   $is_global   Optional. Whether option name is global or blog specific.
 *                            Default false (blog specific).
 * @return bool True on success, false on failure.
 */
function delete_user_option( $user_id, $option_name, $is_global = false ) {
	global $wpdb;

	if ( ! $is_global ) {
		$option_name = $wpdb->get_blog_prefix() . $option_name;
	}

	return delete_user_meta( $user_id, $option_name );
}

/**
 * Retrieves list of users matching criteria.
 *
 * @since 3.1.0
 *
 * @see WP_User_Query
 *
 * @param array $args Optional. Arguments to retrieve users. See WP_User_Query::prepare_query()
 *                    for more information on accepted arguments.
 * @return array List of users.
 */
function get_users( $args = array() ) {

	$args                = wp_parse_args( $args );
	$args['count_total'] = false;

	$user_search = new WP_User_Query( $args );

	return (array) $user_search->get_results();
}

/**
 * Lists all the users of the site, with several options available.
 *
 * @since 5.9.0
 *
 * @param string|array $args {
 *     Optional. Array or string of default arguments.
 *
 *     @type string $orderby       How to sort the users. Accepts 'nicename', 'email', 'url', 'registered',
 *                                 'user_nicename', 'user_email', 'user_url', 'user_registered', 'name',
 *                                 'display_name', 'post_count', 'ID', 'meta_value', 'user_login'. Default 'name'.
 *     @type string $order         Sorting direction for $orderby. Accepts 'ASC', 'DESC'. Default 'ASC'.
 *     @type int    $number        Maximum users to return or display. Default empty (all users).
 *     @type bool   $exclude_admin Whether to exclude the 'admin' account, if it exists. Default false.
 *     @type bool   $show_fullname Whether to show the user's full name. Default false.
 *     @type string $feed          If not empty, show a link to the user's feed and use this text as the alt
 *                                 parameter of the link. Default empty.
 *     @type string $feed_image    If not empty, show a link to the user's feed and use this image URL as
 *                                 clickable anchor. Default empty.
 *     @type string $feed_type     The feed type to link to, such as 'rss2'. Defaults to default feed type.
 *     @type bool   $echo          Whether to output the result or instead return it. Default true.
 *     @type string $style         If 'list', each user is wrapped in an `<li>` element, otherwise the users
 *                                 will be separated by commas.
 *     @type bool   $html          Whether to list the items in HTML form or plaintext. Default true.
 *     @type string $exclude       An array, comma-, or space-separated list of user IDs to exclude. Default empty.
 *     @type string $include       An array, comma-, or space-separated list of user IDs to include. Default empty.
 * }
 * @return string|null The output if echo is false. Otherwise null.
 */
function wp_list_users( $args = array() ) {
	$defaults = array(
		'orderby'       => 'name',
		'order'         => 'ASC',
		'number'        => '',
		'exclude_admin' => true,
		'show_fullname' => false,
		'feed'          => '',
		'feed_image'    => '',
		'feed_type'     => '',
		'echo'          => true,
		'style'         => 'list',
		'html'          => true,
		'exclude'       => '',
		'include'       => '',
	);

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

	$return = '';

	$query_args           = wp_array_slice_assoc( $parsed_args, array( 'orderby', 'order', 'number', 'exclude', 'include' ) );
	$query_args['fields'] = 'ids';

	/**
	 * Filters the query arguments for the list of all users of the site.
	 *
	 * @since 6.1.0
	 *
	 * @param array $query_args  The query arguments for get_users().
	 * @param array $parsed_args The arguments passed to wp_list_users() combined with the defaults.
	 */
	$query_args = apply_filters( 'wp_list_users_args', $query_args, $parsed_args );

	$users = get_users( $query_args );

	foreach ( $users as $user_id ) {
		$user = get_userdata( $user_id );

		if ( $parsed_args['exclude_admin'] && 'admin' === $user->display_name ) {
			continue;
		}

		if ( $parsed_args['show_fullname'] && '' !== $user->first_name && '' !== $user->last_name ) {
			$name = sprintf(
				/* translators: 1: User's first name, 2: Last name. */
				_x( '%1$s %2$s', 'Display name based on first name and last name' ),
				$user->first_name,
				$user->last_name
			);
		} else {
			$name = $user->display_name;
		}

		if ( ! $parsed_args['html'] ) {
			$return .= $name . ', ';

			continue; // No need to go further to process HTML.
		}

		if ( 'list' === $parsed_args['style'] ) {
			$return .= '<li>';
		}

		$row = $name;

		if ( ! empty( $parsed_args['feed_image'] ) || ! empty( $parsed_args['feed'] ) ) {
			$row .= ' ';
			if ( empty( $parsed_args['feed_image'] ) ) {
				$row .= '(';
			}

			$row .= '<a href="' . get_author_feed_link( $user->ID, $parsed_args['feed_type'] ) . '"';

			$alt = '';
			if ( ! empty( $parsed_args['feed'] ) ) {
				$alt  = ' alt="' . esc_attr( $parsed_args['feed'] ) . '"';
				$name = $parsed_args['feed'];
			}

			$row .= '>';

			if ( ! empty( $parsed_args['feed_image'] ) ) {
				$row .= '<img src="' . esc_url( $parsed_args['feed_image'] ) . '" style="border: none;"' . $alt . ' />';
			} else {
				$row .= $name;
			}

			$row .= '</a>';

			if ( empty( $parsed_args['feed_image'] ) ) {
				$row .= ')';
			}
		}

		$return .= $row;
		$return .= ( 'list' === $parsed_args['style'] ) ? '</li>' : ', ';
	}

	$return = rtrim( $return, ', ' );

	if ( ! $parsed_args['echo'] ) {
		return $return;
	}
	echo $return;
}

/**
 * Gets the sites a user belongs to.
 *
 * @since 3.0.0
 * @since 4.7.0 Converted to use `get_sites()`.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int  $user_id User ID
 * @param bool $all     Whether to retrieve all sites, or only sites that are not
 *                      marked as deleted, archived, or spam.
 * @return object[] A list of the user's sites. An empty array if the user doesn't exist
 *                  or belongs to no sites.
 */
function get_blogs_of_user( $user_id, $all = false ) {
	global $wpdb;

	$user_id = (int) $user_id;

	// Logged out users can't have sites.
	if ( empty( $user_id ) ) {
		return array();
	}

	/**
	 * Filters the list of a user's sites before it is populated.
	 *
	 * Returning a non-null value from the filter will effectively short circuit
	 * get_blogs_of_user(), returning that value instead.
	 *
	 * @since 4.6.0
	 *
	 * @param null|object[] $sites   An array of site objects of which the user is a member.
	 * @param int           $user_id User ID.
	 * @param bool          $all     Whether the returned array should contain all sites, including
	 *                               those marked 'deleted', 'archived', or 'spam'. Default false.
	 */
	$sites = apply_filters( 'pre_get_blogs_of_user', null, $user_id, $all );

	if ( null !== $sites ) {
		return $sites;
	}

	$keys = get_user_meta( $user_id );
	if ( empty( $keys ) ) {
		return array();
	}

	if ( ! is_multisite() ) {
		$site_id                        = get_current_blog_id();
		$sites                          = array( $site_id => new stdClass() );
		$sites[ $site_id ]->userblog_id = $site_id;
		$sites[ $site_id ]->blogname    = get_option( 'blogname' );
		$sites[ $site_id ]->domain      = '';
		$sites[ $site_id ]->path        = '';
		$sites[ $site_id ]->site_id     = 1;
		$sites[ $site_id ]->siteurl     = get_option( 'siteurl' );
		$sites[ $site_id ]->archived    = 0;
		$sites[ $site_id ]->spam        = 0;
		$sites[ $site_id ]->deleted     = 0;
		return $sites;
	}

	$site_ids = array();

	if ( isset( $keys[ $wpdb->base_prefix . 'capabilities' ] ) && defined( 'MULTISITE' ) ) {
		$site_ids[] = 1;
		unset( $keys[ $wpdb->base_prefix . 'capabilities' ] );
	}

	$keys = array_keys( $keys );

	foreach ( $keys as $key ) {
		if ( ! str_ends_with( $key, 'capabilities' ) ) {
			continue;
		}
		if ( $wpdb->base_prefix && ! str_starts_with( $key, $wpdb->base_prefix ) ) {
			continue;
		}
		$site_id = str_replace( array( $wpdb->base_prefix, '_capabilities' ), '', $key );
		if ( ! is_numeric( $site_id ) ) {
			continue;
		}

		$site_ids[] = (int) $site_id;
	}

	$sites = array();

	if ( ! empty( $site_ids ) ) {
		$args = array(
			'number'   => '',
			'site__in' => $site_ids,
		);
		if ( ! $all ) {
			$args['archived'] = 0;
			$args['spam']     = 0;
			$args['deleted']  = 0;
		}

		$_sites = get_sites( $args );

		foreach ( $_sites as $site ) {
			$sites[ $site->id ] = (object) array(
				'userblog_id' => $site->id,
				'blogname'    => $site->blogname,
				'domain'      => $site->domain,
				'path'        => $site->path,
				'site_id'     => $site->network_id,
				'siteurl'     => $site->siteurl,
				'archived'    => $site->archived,
				'mature'      => $site->mature,
				'spam'        => $site->spam,
				'deleted'     => $site->deleted,
			);
		}
	}

	/**
	 * Filters the list of sites a user belongs to.
	 *
	 * @since MU (3.0.0)
	 *
	 * @param object[] $sites   An array of site objects belonging to the user.
	 * @param int      $user_id User ID.
	 * @param bool     $all     Whether the returned sites array should contain all sites, including
	 *                          those marked 'deleted', 'archived', or 'spam'. Default false.
	 */
	return apply_filters( 'get_blogs_of_user', $sites, $user_id, $all );
}

/**
 * Finds out whether a user is a member of a given blog.
 *
 * @since MU (3.0.0)
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int $user_id Optional. The unique ID of the user. Defaults to the current user.
 * @param int $blog_id Optional. ID of the blog to check. Defaults to the current site.
 * @return bool
 */
function is_user_member_of_blog( $user_id = 0, $blog_id = 0 ) {
	global $wpdb;

	$user_id = (int) $user_id;
	$blog_id = (int) $blog_id;

	if ( empty( $user_id ) ) {
		$user_id = get_current_user_id();
	}

	/*
	 * Technically not needed, but does save calls to get_site() and get_user_meta()
	 * in the event that the function is called when a user isn't logged in.
	 */
	if ( empty( $user_id ) ) {
		return false;
	} else {
		$user = get_userdata( $user_id );
		if ( ! $user instanceof WP_User ) {
			return false;
		}
	}

	if ( ! is_multisite() ) {
		return true;
	}

	if ( empty( $blog_id ) ) {
		$blog_id = get_current_blog_id();
	}

	$blog = get_site( $blog_id );

	if ( ! $blog || ! isset( $blog->domain ) || $blog->archived || $blog->spam || $blog->deleted ) {
		return false;
	}

	$keys = get_user_meta( $user_id );
	if ( empty( $keys ) ) {
		return false;
	}

	// No underscore before capabilities in $base_capabilities_key.
	$base_capabilities_key = $wpdb->base_prefix . 'capabilities';
	$site_capabilities_key = $wpdb->base_prefix . $blog_id . '_capabilities';

	if ( isset( $keys[ $base_capabilities_key ] ) && 1 == $blog_id ) {
		return true;
	}

	if ( isset( $keys[ $site_capabilities_key ] ) ) {
		return true;
	}

	return false;
}

/**
 * Adds meta data to a user.
 *
 * @since 3.0.0
 *
 * @param int    $user_id    User ID.
 * @param string $meta_key   Metadata name.
 * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
 * @param bool   $unique     Optional. Whether the same key should not be added.
 *                           Default false.
 * @return int|false Meta ID on success, false on failure.
 */
function add_user_meta( $user_id, $meta_key, $meta_value, $unique = false ) {
	return add_metadata( 'user', $user_id, $meta_key, $meta_value, $unique );
}

/**
 * Removes metadata matching criteria from a user.
 *
 * You can match based on the key, or key and value. Removing based on key and
 * value, will keep from removing duplicate metadata with the same key. It also
 * allows removing all metadata matching key, if needed.
 *
 * @since 3.0.0
 *
 * @link https://developer.wordpress.org/reference/functions/delete_user_meta/
 *
 * @param int    $user_id    User ID
 * @param string $meta_key   Metadata name.
 * @param mixed  $meta_value Optional. Metadata value. If provided,
 *                           rows will only be removed that match the value.
 *                           Must be serializable if non-scalar. Default empty.
 * @return bool True on success, false on failure.
 */
function delete_user_meta( $user_id, $meta_key, $meta_value = '' ) {
	return delete_metadata( 'user', $user_id, $meta_key, $meta_value );
}

/**
 * Retrieves user meta field for a user.
 *
 * @since 3.0.0
 *
 * @link https://developer.wordpress.org/reference/functions/get_user_meta/
 *
 * @param int    $user_id User ID.
 * @param string $key     Optional. The meta key to retrieve. By default,
 *                        returns data for all keys.
 * @param bool   $single  Optional. Whether to return a single value.
 *                        This parameter has no effect if `$key` is not specified.
 *                        Default false.
 * @return mixed An array of values if `$single` is false.
 *               The value of meta data field if `$single` is true.
 *               False for an invalid `$user_id` (non-numeric, zero, or negative value).
 *               An empty string if a valid but non-existing user ID is passed.
 */
function get_user_meta( $user_id, $key = '', $single = false ) {
	return get_metadata( 'user', $user_id, $key, $single );
}

/**
 * Updates user meta field based on user ID.
 *
 * Use the $prev_value parameter to differentiate between meta fields with the
 * same key and user ID.
 *
 * If the meta field for the user does not exist, it will be added.
 *
 * @since 3.0.0
 *
 * @link https://developer.wordpress.org/reference/functions/update_user_meta/
 *
 * @param int    $user_id    User ID.
 * @param string $meta_key   Metadata key.
 * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
 * @param mixed  $prev_value Optional. Previous value to check before updating.
 *                           If specified, only update existing metadata entries with
 *                           this value. Otherwise, update all entries. Default empty.
 * @return int|bool Meta ID if the key didn't exist, true on successful update,
 *                  false on failure or if the value passed to the function
 *                  is the same as the one that is already in the database.
 */
function update_user_meta( $user_id, $meta_key, $meta_value, $prev_value = '' ) {
	return update_metadata( 'user', $user_id, $meta_key, $meta_value, $prev_value );
}

/**
 * Counts number of users who have each of the user roles.
 *
 * Assumes there are neither duplicated nor orphaned capabilities meta_values.
 * Assumes role names are unique phrases. Same assumption made by WP_User_Query::prepare_query()
 * Using $strategy = 'time' this is CPU-intensive and should handle around 10^7 users.
 * Using $strategy = 'memory' this is memory-intensive and should handle around 10^5 users, but see WP Bug #12257.
 *
 * @since 3.0.0
 * @since 4.4.0 The number of users with no role is now included in the `none` element.
 * @since 4.9.0 The `$site_id` parameter was added to support multisite.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string   $strategy Optional. The computational strategy to use when counting the users.
 *                           Accepts either 'time' or 'memory'. Default 'time'.
 * @param int|null $site_id  Optional. The site ID to count users for. Defaults to the current site.
 * @return array {
 *     User counts.
 *
 *     @type int   $total_users Total number of users on the site.
 *     @type int[] $avail_roles Array of user counts keyed by user role.
 * }
 */
function count_users( $strategy = 'time', $site_id = null ) {
	global $wpdb;

	// Initialize.
	if ( ! $site_id ) {
		$site_id = get_current_blog_id();
	}

	/**
	 * Filters the user count before queries are run.
	 *
	 * Return a non-null value to cause count_users() to return early.
	 *
	 * @since 5.1.0
	 *
	 * @param null|array $result   The value to return instead. Default null to continue with the query.
	 * @param string     $strategy Optional. The computational strategy to use when counting the users.
	 *                             Accepts either 'time' or 'memory'. Default 'time'.
	 * @param int        $site_id  The site ID to count users for.
	 */
	$pre = apply_filters( 'pre_count_users', null, $strategy, $site_id );

	if ( null !== $pre ) {
		return $pre;
	}

	$blog_prefix = $wpdb->get_blog_prefix( $site_id );
	$result      = array();

	if ( 'time' === $strategy ) {
		if ( is_multisite() && get_current_blog_id() != $site_id ) {
			switch_to_blog( $site_id );
			$avail_roles = wp_roles()->get_names();
			restore_current_blog();
		} else {
			$avail_roles = wp_roles()->get_names();
		}

		// Build a CPU-intensive query that will return concise information.
		$select_count = array();
		foreach ( $avail_roles as $this_role => $name ) {
			$select_count[] = $wpdb->prepare( 'COUNT(NULLIF(`meta_value` LIKE %s, false))', '%' . $wpdb->esc_like( '"' . $this_role . '"' ) . '%' );
		}
		$select_count[] = "COUNT(NULLIF(`meta_value` = 'a:0:{}', false))";
		$select_count   = implode( ', ', $select_count );

		// Add the meta_value index to the selection list, then run the query.
		$row = $wpdb->get_row(
			"
			SELECT {$select_count}, COUNT(*)
			FROM {$wpdb->usermeta}
			INNER JOIN {$wpdb->users} ON user_id = ID
			WHERE meta_key = '{$blog_prefix}capabilities'
		",
			ARRAY_N
		);

		// Run the previous loop again to associate results with role names.
		$col         = 0;
		$role_counts = array();
		foreach ( $avail_roles as $this_role => $name ) {
			$count = (int) $row[ $col++ ];
			if ( $count > 0 ) {
				$role_counts[ $this_role ] = $count;
			}
		}

		$role_counts['none'] = (int) $row[ $col++ ];

		// Get the meta_value index from the end of the result set.
		$total_users = (int) $row[ $col ];

		$result['total_users'] = $total_users;
		$result['avail_roles'] =& $role_counts;
	} else {
		$avail_roles = array(
			'none' => 0,
		);

		$users_of_blog = $wpdb->get_col(
			"
			SELECT meta_value
			FROM {$wpdb->usermeta}
			INNER JOIN {$wpdb->users} ON user_id = ID
			WHERE meta_key = '{$blog_prefix}capabilities'
		"
		);

		foreach ( $users_of_blog as $caps_meta ) {
			$b_roles = maybe_unserialize( $caps_meta );
			if ( ! is_array( $b_roles ) ) {
				continue;
			}
			if ( empty( $b_roles ) ) {
				++$avail_roles['none'];
			}
			foreach ( $b_roles as $b_role => $val ) {
				if ( isset( $avail_roles[ $b_role ] ) ) {
					++$avail_roles[ $b_role ];
				} else {
					$avail_roles[ $b_role ] = 1;
				}
			}
		}

		$result['total_users'] = count( $users_of_blog );
		$result['avail_roles'] =& $avail_roles;
	}

	return $result;
}

/**
 * Returns the number of active users in your installation.
 *
 * Note that on a large site the count may be cached and only updated twice daily.
 *
 * @since MU (3.0.0)
 * @since 4.8.0 The `$network_id` parameter has been added.
 * @since 6.0.0 Moved to wp-includes/user.php.
 *
 * @param int|null $network_id ID of the network. Defaults to the current network.
 * @return int Number of active users on the network.
 */
function get_user_count( $network_id = null ) {
	if ( ! is_multisite() && null !== $network_id ) {
		_doing_it_wrong(
			__FUNCTION__,
			sprintf(
				/* translators: %s: $network_id */
				__( 'Unable to pass %s if not using multisite.' ),
				'<code>$network_id</code>'
			),
			'6.0.0'
		);
	}

	return (int) get_network_option( $network_id, 'user_count', -1 );
}

/**
 * Updates the total count of users on the site if live user counting is enabled.
 *
 * @since 6.0.0
 *
 * @param int|null $network_id ID of the network. Defaults to the current network.
 * @return bool Whether the update was successful.
 */
function wp_maybe_update_user_counts( $network_id = null ) {
	if ( ! is_multisite() && null !== $network_id ) {
		_doing_it_wrong(
			__FUNCTION__,
			sprintf(
				/* translators: %s: $network_id */
				__( 'Unable to pass %s if not using multisite.' ),
				'<code>$network_id</code>'
			),
			'6.0.0'
		);
	}

	$is_small_network = ! wp_is_large_user_count( $network_id );
	/** This filter is documented in wp-includes/ms-functions.php */
	if ( ! apply_filters( 'enable_live_network_counts', $is_small_network, 'users' ) ) {
		return false;
	}

	return wp_update_user_counts( $network_id );
}

/**
 * Updates the total count of users on the site.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 * @since 6.0.0
 *
 * @param int|null $network_id ID of the network. Defaults to the current network.
 * @return bool Whether the update was successful.
 */
function wp_update_user_counts( $network_id = null ) {
	global $wpdb;

	if ( ! is_multisite() && null !== $network_id ) {
		_doing_it_wrong(
			__FUNCTION__,
			sprintf(
				/* translators: %s: $network_id */
				__( 'Unable to pass %s if not using multisite.' ),
				'<code>$network_id</code>'
			),
			'6.0.0'
		);
	}

	$query = "SELECT COUNT(ID) as c FROM $wpdb->users";
	if ( is_multisite() ) {
		$query .= " WHERE spam = '0' AND deleted = '0'";
	}

	$count = $wpdb->get_var( $query );

	return update_network_option( $network_id, 'user_count', $count );
}

/**
 * Schedules a recurring recalculation of the total count of users.
 *
 * @since 6.0.0
 */
function wp_schedule_update_user_counts() {
	if ( ! is_main_site() ) {
		return;
	}

	if ( ! wp_next_scheduled( 'wp_update_user_counts' ) && ! wp_installing() ) {
		wp_schedule_event( time(), 'twicedaily', 'wp_update_user_counts' );
	}
}

/**
 * Determines whether the site has a large number of users.
 *
 * The default criteria for a large site is more than 10,000 users.
 *
 * @since 6.0.0
 *
 * @param int|null $network_id ID of the network. Defaults to the current network.
 * @return bool Whether the site has a large number of users.
 */
function wp_is_large_user_count( $network_id = null ) {
	if ( ! is_multisite() && null !== $network_id ) {
		_doing_it_wrong(
			__FUNCTION__,
			sprintf(
				/* translators: %s: $network_id */
				__( 'Unable to pass %s if not using multisite.' ),
				'<code>$network_id</code>'
			),
			'6.0.0'
		);
	}

	$count = get_user_count( $network_id );

	/**
	 * Filters whether the site is considered large, based on its number of users.
	 *
	 * @since 6.0.0
	 *
	 * @param bool     $is_large_user_count Whether the site has a large number of users.
	 * @param int      $count               The total number of users.
	 * @param int|null $network_id          ID of the network. `null` represents the current network.
	 */
	return apply_filters( 'wp_is_large_user_count', $count > 10000, $count, $network_id );
}

//
// Private helper functions.
//

/**
 * Sets up global user vars.
 *
 * Used by wp_set_current_user() for back compat. Might be deprecated in the future.
 *
 * @since 2.0.4
 *
 * @global string  $user_login    The user username for logging in
 * @global WP_User $userdata      User data.
 * @global int     $user_level    The level of the user
 * @global int     $user_ID       The ID of the user
 * @global string  $user_email    The email address of the user
 * @global string  $user_url      The url in the user's profile
 * @global string  $user_identity The display name of the user
 *
 * @param int $for_user_id Optional. User ID to set up global data. Default 0.
 */
function setup_userdata( $for_user_id = 0 ) {
	global $user_login, $userdata, $user_level, $user_ID, $user_email, $user_url, $user_identity;

	if ( ! $for_user_id ) {
		$for_user_id = get_current_user_id();
	}
	$user = get_userdata( $for_user_id );

	if ( ! $user ) {
		$user_ID       = 0;
		$user_level    = 0;
		$userdata      = null;
		$user_login    = '';
		$user_email    = '';
		$user_url      = '';
		$user_identity = '';
		return;
	}

	$user_ID       = (int) $user->ID;
	$user_level    = (int) $user->user_level;
	$userdata      = $user;
	$user_login    = $user->user_login;
	$user_email    = $user->user_email;
	$user_url      = $user->user_url;
	$user_identity = $user->display_name;
}

/**
 * Creates dropdown HTML content of users.
 *
 * The content can either be displayed, which it is by default or retrieved by
 * setting the 'echo' argument. The 'include' and 'exclude' arguments do not
 * need to be used; all users will be displayed in that case. Only one can be
 * used, either 'include' or 'exclude', but not both.
 *
 * The available arguments are as follows:
 *
 * @since 2.3.0
 * @since 4.5.0 Added the 'display_name_with_login' value for 'show'.
 * @since 4.7.0 Added the `$role`, `$role__in`, and `$role__not_in` parameters.
 *
 * @param array|string $args {
 *     Optional. Array or string of arguments to generate a drop-down of users.
 *     See WP_User_Query::prepare_query() for additional available arguments.
 *
 *     @type string       $show_option_all         Text to show as the drop-down default (all).
 *                                                 Default empty.
 *     @type string       $show_option_none        Text to show as the drop-down default when no
 *                                                 users were found. Default empty.
 *     @type int|string   $option_none_value       Value to use for $show_option_none when no users
 *                                                 were found. Default -1.
 *     @type string       $hide_if_only_one_author Whether to skip generating the drop-down
 *                                                 if only one user was found. Default empty.
 *     @type string       $orderby                 Field to order found users by. Accepts user fields.
 *                                                 Default 'display_name'.
 *     @type string       $order                   Whether to order users in ascending or descending
 *                                                 order. Accepts 'ASC' (ascending) or 'DESC' (descending).
 *                                                 Default 'ASC'.
 *     @type int[]|string $include                 Array or comma-separated list of user IDs to include.
 *                                                 Default empty.
 *     @type int[]|string $exclude                 Array or comma-separated list of user IDs to exclude.
 *                                                 Default empty.
 *     @type bool|int     $multi                   Whether to skip the ID attribute on the 'select' element.
 *                                                 Accepts 1|true or 0|false. Default 0|false.
 *     @type string       $show                    User data to display. If the selected item is empty
 *                                                 then the 'user_login' will be displayed in parentheses.
 *                                                 Accepts any user field, or 'display_name_with_login' to show
 *                                                 the display name with user_login in parentheses.
 *                                                 Default 'display_name'.
 *     @type int|bool     $echo                    Whether to echo or return the drop-down. Accepts 1|true (echo)
 *                                                 or 0|false (return). Default 1|true.
 *     @type int          $selected                Which user ID should be selected. Default 0.
 *     @type bool         $include_selected        Whether to always include the selected user ID in the drop-
 *                                                 down. Default false.
 *     @type string       $name                    Name attribute of select element. Default 'user'.
 *     @type string       $id                      ID attribute of the select element. Default is the value of $name.
 *     @type string       $class                   Class attribute of the select element. Default empty.
 *     @type int          $blog_id                 ID of blog (Multisite only). Default is ID of the current blog.
 *     @type string       $who                     Which type of users to query. Accepts only an empty string or
 *                                                 'authors'. Default empty.
 *     @type string|array $role                    An array or a comma-separated list of role names that users must
 *                                                 match to be included in results. Note that this is an inclusive
 *                                                 list: users must match *each* role. Default empty.
 *     @type string[]     $role__in                An array of role names. Matched users must have at least one of
 *                                                 these roles. Default empty array.
 *     @type string[]     $role__not_in            An array of role names to exclude. Users matching one or more of
 *                                                 these roles will not be included in results. Default empty array.
 * }
 * @return string HTML dropdown list of users.
 */
function wp_dropdown_users( $args = '' ) {
	$defaults = array(
		'show_option_all'         => '',
		'show_option_none'        => '',
		'hide_if_only_one_author' => '',
		'orderby'                 => 'display_name',
		'order'                   => 'ASC',
		'include'                 => '',
		'exclude'                 => '',
		'multi'                   => 0,
		'show'                    => 'display_name',
		'echo'                    => 1,
		'selected'                => 0,
		'name'                    => 'user',
		'class'                   => '',
		'id'                      => '',
		'blog_id'                 => get_current_blog_id(),
		'who'                     => '',
		'include_selected'        => false,
		'option_none_value'       => -1,
		'role'                    => '',
		'role__in'                => array(),
		'role__not_in'            => array(),
		'capability'              => '',
		'capability__in'          => array(),
		'capability__not_in'      => array(),
	);

	$defaults['selected'] = is_author() ? get_query_var( 'author' ) : 0;

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

	$query_args = wp_array_slice_assoc(
		$parsed_args,
		array(
			'blog_id',
			'include',
			'exclude',
			'orderby',
			'order',
			'who',
			'role',
			'role__in',
			'role__not_in',
			'capability',
			'capability__in',
			'capability__not_in',
		)
	);

	$fields = array( 'ID', 'user_login' );

	$show = ! empty( $parsed_args['show'] ) ? $parsed_args['show'] : 'display_name';
	if ( 'display_name_with_login' === $show ) {
		$fields[] = 'display_name';
	} else {
		$fields[] = $show;
	}

	$query_args['fields'] = $fields;

	$show_option_all   = $parsed_args['show_option_all'];
	$show_option_none  = $parsed_args['show_option_none'];
	$option_none_value = $parsed_args['option_none_value'];

	/**
	 * Filters the query arguments for the list of users in the dropdown.
	 *
	 * @since 4.4.0
	 *
	 * @param array $query_args  The query arguments for get_users().
	 * @param array $parsed_args The arguments passed to wp_dropdown_users() combined with the defaults.
	 */
	$query_args = apply_filters( 'wp_dropdown_users_args', $query_args, $parsed_args );

	$users = get_users( $query_args );

	$output = '';
	if ( ! empty( $users ) && ( empty( $parsed_args['hide_if_only_one_author'] ) || count( $users ) > 1 ) ) {
		$name = esc_attr( $parsed_args['name'] );
		if ( $parsed_args['multi'] && ! $parsed_args['id'] ) {
			$id = '';
		} else {
			$id = $parsed_args['id'] ? " id='" . esc_attr( $parsed_args['id'] ) . "'" : " id='$name'";
		}
		$output = "<select name='{$name}'{$id} class='" . $parsed_args['class'] . "'>\n";

		if ( $show_option_all ) {
			$output .= "\t<option value='0'>$show_option_all</option>\n";
		}

		if ( $show_option_none ) {
			$_selected = selected( $option_none_value, $parsed_args['selected'], false );
			$output   .= "\t<option value='" . esc_attr( $option_none_value ) . "'$_selected>$show_option_none</option>\n";
		}

		if ( $parsed_args['include_selected'] && ( $parsed_args['selected'] > 0 ) ) {
			$found_selected          = false;
			$parsed_args['selected'] = (int) $parsed_args['selected'];

			foreach ( (array) $users as $user ) {
				$user->ID = (int) $user->ID;
				if ( $user->ID === $parsed_args['selected'] ) {
					$found_selected = true;
				}
			}

			if ( ! $found_selected ) {
				$selected_user = get_userdata( $parsed_args['selected'] );
				if ( $selected_user ) {
					$users[] = $selected_user;
				}
			}
		}

		foreach ( (array) $users as $user ) {
			if ( 'display_name_with_login' === $show ) {
				/* translators: 1: User's display name, 2: User login. */
				$display = sprintf( _x( '%1$s (%2$s)', 'user dropdown' ), $user->display_name, $user->user_login );
			} elseif ( ! empty( $user->$show ) ) {
				$display = $user->$show;
			} else {
				$display = '(' . $user->user_login . ')';
			}

			$_selected = selected( $user->ID, $parsed_args['selected'], false );
			$output   .= "\t<option value='$user->ID'$_selected>" . esc_html( $display ) . "</option>\n";
		}

		$output .= '</select>';
	}

	/**
	 * Filters the wp_dropdown_users() HTML output.
	 *
	 * @since 2.3.0
	 *
	 * @param string $output HTML output generated by wp_dropdown_users().
	 */
	$html = apply_filters( 'wp_dropdown_users', $output );

	if ( $parsed_args['echo'] ) {
		echo $html;
	}
	return $html;
}

/**
 * Sanitizes user field based on context.
 *
 * Possible context values are:  'raw', 'edit', 'db', 'display', 'attribute' and 'js'. The
 * 'display' context is used by default. 'attribute' and 'js' contexts are treated like 'display'
 * when calling filters.
 *
 * @since 2.3.0
 *
 * @param string $field   The user Object field name.
 * @param mixed  $value   The user Object value.
 * @param int    $user_id User ID.
 * @param string $context How to sanitize user fields. Looks for 'raw', 'edit', 'db', 'display',
 *                        'attribute' and 'js'.
 * @return mixed Sanitized value.
 */
function sanitize_user_field( $field, $value, $user_id, $context ) {
	$int_fields = array( 'ID' );
	if ( in_array( $field, $int_fields, true ) ) {
		$value = (int) $value;
	}

	if ( 'raw' === $context ) {
		return $value;
	}

	if ( ! is_string( $value ) && ! is_numeric( $value ) ) {
		return $value;
	}

	$prefixed = str_contains( $field, 'user_' );

	if ( 'edit' === $context ) {
		if ( $prefixed ) {

			/** This filter is documented in wp-includes/post.php */
			$value = apply_filters( "edit_{$field}", $value, $user_id );
		} else {

			/**
			 * Filters a user field value in the 'edit' context.
			 *
			 * The dynamic portion of the hook name, `$field`, refers to the prefixed user
			 * field being filtered, such as 'user_login', 'user_email', 'first_name', etc.
			 *
			 * @since 2.9.0
			 *
			 * @param mixed $value   Value of the prefixed user field.
			 * @param int   $user_id User ID.
			 */
			$value = apply_filters( "edit_user_{$field}", $value, $user_id );
		}

		if ( 'description' === $field ) {
			$value = esc_html( $value ); // textarea_escaped?
		} else {
			$value = esc_attr( $value );
		}
	} elseif ( 'db' === $context ) {
		if ( $prefixed ) {
			/** This filter is documented in wp-includes/post.php */
			$value = apply_filters( "pre_{$field}", $value );
		} else {

			/**
			 * Filters the value of a user field in the 'db' context.
			 *
			 * The dynamic portion of the hook name, `$field`, refers to the prefixed user
			 * field being filtered, such as 'user_login', 'user_email', 'first_name', etc.
			 *
			 * @since 2.9.0
			 *
			 * @param mixed $value Value of the prefixed user field.
			 */
			$value = apply_filters( "pre_user_{$field}", $value );
		}
	} else {
		// Use display filters by default.
		if ( $prefixed ) {

			/** This filter is documented in wp-includes/post.php */
			$value = apply_filters( "{$field}", $value, $user_id, $context );
		} else {

			/**
			 * Filters the value of a user field in a standard context.
			 *
			 * The dynamic portion of the hook name, `$field`, refers to the prefixed user
			 * field being filtered, such as 'user_login', 'user_email', 'first_name', etc.
			 *
			 * @since 2.9.0
			 *
			 * @param mixed  $value   The user object value to sanitize.
			 * @param int    $user_id User ID.
			 * @param string $context The context to filter within.
			 */
			$value = apply_filters( "user_{$field}", $value, $user_id, $context );
		}
	}

	if ( 'user_url' === $field ) {
		$value = esc_url( $value );
	}

	if ( 'attribute' === $context ) {
		$value = esc_attr( $value );
	} elseif ( 'js' === $context ) {
		$value = esc_js( $value );
	}

	// Restore the type for integer fields after esc_attr().
	if ( in_array( $field, $int_fields, true ) ) {
		$value = (int) $value;
	}

	return $value;
}

/**
 * Updates all user caches.
 *
 * @since 3.0.0
 *
 * @param object|WP_User $user User object or database row to be cached
 * @return void|false Void on success, false on failure.
 */
function update_user_caches( $user ) {
	if ( $user instanceof WP_User ) {
		if ( ! $user->exists() ) {
			return false;
		}

		$user = $user->data;
	}

	wp_cache_add( $user->ID, $user, 'users' );
	wp_cache_add( $user->user_login, $user->ID, 'userlogins' );
	wp_cache_add( $user->user_nicename, $user->ID, 'userslugs' );

	if ( ! empty( $user->user_email ) ) {
		wp_cache_add( $user->user_email, $user->ID, 'useremail' );
	}
}

/**
 * Cleans all user caches.
 *
 * @since 3.0.0
 * @since 4.4.0 'clean_user_cache' action was added.
 * @since 6.2.0 User metadata caches are now cleared.
 *
 * @param WP_User|int $user User object or ID to be cleaned from the cache
 */
function clean_user_cache( $user ) {
	if ( is_numeric( $user ) ) {
		$user = new WP_User( $user );
	}

	if ( ! $user->exists() ) {
		return;
	}

	wp_cache_delete( $user->ID, 'users' );
	wp_cache_delete( $user->user_login, 'userlogins' );
	wp_cache_delete( $user->user_nicename, 'userslugs' );

	if ( ! empty( $user->user_email ) ) {
		wp_cache_delete( $user->user_email, 'useremail' );
	}

	wp_cache_delete( $user->ID, 'user_meta' );
	wp_cache_set_users_last_changed();

	/**
	 * Fires immediately after the given user's cache is cleaned.
	 *
	 * @since 4.4.0
	 *
	 * @param int     $user_id User ID.
	 * @param WP_User $user    User object.
	 */
	do_action( 'clean_user_cache', $user->ID, $user );
}

/**
 * Determines whether the given username exists.
 *
 * For more information on this and similar theme functions, check out
 * the {@link https://developer.wordpress.org/themes/basics/conditional-tags/
 * Conditional Tags} article in the Theme Developer Handbook.
 *
 * @since 2.0.0
 *
 * @param string $username The username to check for existence.
 * @return int|false The user ID on success, false on failure.
 */
function username_exists( $username ) {
	$user = get_user_by( 'login', $username );
	if ( $user ) {
		$user_id = $user->ID;
	} else {
		$user_id = false;
	}

	/**
	 * Filters whether the given username exists.
	 *
	 * @since 4.9.0
	 *
	 * @param int|false $user_id  The user ID associated with the username,
	 *                            or false if the username does not exist.
	 * @param string    $username The username to check for existence.
	 */
	return apply_filters( 'username_exists', $user_id, $username );
}

/**
 * Determines whether the given email exists.
 *
 * For more information on this and similar theme functions, check out
 * the {@link https://developer.wordpress.org/themes/basics/conditional-tags/
 * Conditional Tags} article in the Theme Developer Handbook.
 *
 * @since 2.1.0
 *
 * @param string $email The email to check for existence.
 * @return int|false The user ID on success, false on failure.
 */
function email_exists( $email ) {
	$user = get_user_by( 'email', $email );
	if ( $user ) {
		$user_id = $user->ID;
	} else {
		$user_id = false;
	}

	/**
	 * Filters whether the given email exists.
	 *
	 * @since 5.6.0
	 *
	 * @param int|false $user_id The user ID associated with the email,
	 *                           or false if the email does not exist.
	 * @param string    $email   The email to check for existence.
	 */
	return apply_filters( 'email_exists', $user_id, $email );
}

/**
 * Checks whether a username is valid.
 *
 * @since 2.0.1
 * @since 4.4.0 Empty sanitized usernames are now considered invalid.
 *
 * @param string $username Username.
 * @return bool Whether username given is valid.
 */
function validate_username( $username ) {
	$sanitized = sanitize_user( $username, true );
	$valid     = ( $sanitized == $username && ! empty( $sanitized ) );

	/**
	 * Filters whether the provided username is valid.
	 *
	 * @since 2.0.1
	 *
	 * @param bool   $valid    Whether given username is valid.
	 * @param string $username Username to check.
	 */
	return apply_filters( 'validate_username', $valid, $username );
}

/**
 * Inserts a user into the database.
 *
 * Most of the `$userdata` array fields have filters associated with the values. Exceptions are
 * 'ID', 'rich_editing', 'syntax_highlighting', 'comment_shortcuts', 'admin_color', 'use_ssl',
 * 'user_registered', 'user_activation_key', 'spam', and 'role'. The filters have the prefix
 * 'pre_user_' followed by the field name. An example using 'description' would have the filter
 * called 'pre_user_description' that can be hooked into.
 *
 * @since 2.0.0
 * @since 3.6.0 The `aim`, `jabber`, and `yim` fields were removed as default user contact
 *              methods for new installations. See wp_get_user_contact_methods().
 * @since 4.7.0 The `locale` field can be passed to `$userdata`.
 * @since 5.3.0 The `user_activation_key` field can be passed to `$userdata`.
 * @since 5.3.0 The `spam` field can be passed to `$userdata` (Multisite only).
 * @since 5.9.0 The `meta_input` field can be passed to `$userdata` to allow addition of user meta data.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param array|object|WP_User $userdata {
 *     An array, object, or WP_User object of user data arguments.
 *
 *     @type int    $ID                   User ID. If supplied, the user will be updated.
 *     @type string $user_pass            The plain-text user password for new users.
 *                                        Hashed password for existing users.
 *     @type string $user_login           The user's login username.
 *     @type string $user_nicename        The URL-friendly user name.
 *     @type string $user_url             The user URL.
 *     @type string $user_email           The user email address.
 *     @type string $display_name         The user's display name.
 *                                        Default is the user's username.
 *     @type string $nickname             The user's nickname.
 *                                        Default is the user's username.
 *     @type string $first_name           The user's first name. For new users, will be used
 *                                        to build the first part of the user's display name
 *                                        if `$display_name` is not specified.
 *     @type string $last_name            The user's last name. For new users, will be used
 *                                        to build the second part of the user's display name
 *                                        if `$display_name` is not specified.
 *     @type string $description          The user's biographical description.
 *     @type string $rich_editing         Whether to enable the rich-editor for the user.
 *                                        Accepts 'true' or 'false' as a string literal,
 *                                        not boolean. Default 'true'.
 *     @type string $syntax_highlighting  Whether to enable the rich code editor for the user.
 *                                        Accepts 'true' or 'false' as a string literal,
 *                                        not boolean. Default 'true'.
 *     @type string $comment_shortcuts    Whether to enable comment moderation keyboard
 *                                        shortcuts for the user. Accepts 'true' or 'false'
 *                                        as a string literal, not boolean. Default 'false'.
 *     @type string $admin_color          Admin color scheme for the user. Default 'fresh'.
 *     @type bool   $use_ssl              Whether the user should always access the admin over
 *                                        https. Default false.
 *     @type string $user_registered      Date the user registered in UTC. Format is 'Y-m-d H:i:s'.
 *     @type string $user_activation_key  Password reset key. Default empty.
 *     @type bool   $spam                 Multisite only. Whether the user is marked as spam.
 *                                        Default false.
 *     @type string $show_admin_bar_front Whether to display the Admin Bar for the user
 *                                        on the site's front end. Accepts 'true' or 'false'
 *                                        as a string literal, not boolean. Default 'true'.
 *     @type string $role                 User's role.
 *     @type string $locale               User's locale. Default empty.
 *     @type array  $meta_input           Array of custom user meta values keyed by meta key.
 *                                        Default empty.
 * }
 * @return int|WP_Error The newly created user's ID or a WP_Error object if the user could not
 *                      be created.
 */
function wp_insert_user( $userdata ) {
	global $wpdb;

	if ( $userdata instanceof stdClass ) {
		$userdata = get_object_vars( $userdata );
	} elseif ( $userdata instanceof WP_User ) {
		$userdata = $userdata->to_array();
	}

	// Are we updating or creating?
	if ( ! empty( $userdata['ID'] ) ) {
		$user_id       = (int) $userdata['ID'];
		$update        = true;
		$old_user_data = get_userdata( $user_id );

		if ( ! $old_user_data ) {
			return new WP_Error( 'invalid_user_id', __( 'Invalid user ID.' ) );
		}

		// Hashed in wp_update_user(), plaintext if called directly.
		$user_pass = ! empty( $userdata['user_pass'] ) ? $userdata['user_pass'] : $old_user_data->user_pass;
	} else {
		$update = false;
		// Hash the password.
		$user_pass = wp_hash_password( $userdata['user_pass'] );
	}

	$sanitized_user_login = sanitize_user( $userdata['user_login'], true );

	/**
	 * Filters a username after it has been sanitized.
	 *
	 * This filter is called before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $sanitized_user_login Username after it has been sanitized.
	 */
	$pre_user_login = apply_filters( 'pre_user_login', $sanitized_user_login );

	// Remove any non-printable chars from the login string to see if we have ended up with an empty username.
	$user_login = trim( $pre_user_login );

	// user_login must be between 0 and 60 characters.
	if ( empty( $user_login ) ) {
		return new WP_Error( 'empty_user_login', __( 'Cannot create a user with an empty login name.' ) );
	} elseif ( mb_strlen( $user_login ) > 60 ) {
		return new WP_Error( 'user_login_too_long', __( 'Username may not be longer than 60 characters.' ) );
	}

	if ( ! $update && username_exists( $user_login ) ) {
		return new WP_Error( 'existing_user_login', __( 'Sorry, that username already exists!' ) );
	}

	/**
	 * Filters the list of disallowed usernames.
	 *
	 * @since 4.4.0
	 *
	 * @param array $usernames Array of disallowed usernames.
	 */
	$illegal_logins = (array) apply_filters( 'illegal_user_logins', array() );

	if ( in_array( strtolower( $user_login ), array_map( 'strtolower', $illegal_logins ), true ) ) {
		return new WP_Error( 'invalid_username', __( 'Sorry, that username is not allowed.' ) );
	}

	/*
	 * If a nicename is provided, remove unsafe user characters before using it.
	 * Otherwise build a nicename from the user_login.
	 */
	if ( ! empty( $userdata['user_nicename'] ) ) {
		$user_nicename = sanitize_user( $userdata['user_nicename'], true );
	} else {
		$user_nicename = mb_substr( $user_login, 0, 50 );
	}

	$user_nicename = sanitize_title( $user_nicename );

	/**
	 * Filters a user's nicename before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $user_nicename The user's nicename.
	 */
	$user_nicename = apply_filters( 'pre_user_nicename', $user_nicename );

	if ( mb_strlen( $user_nicename ) > 50 ) {
		return new WP_Error( 'user_nicename_too_long', __( 'Nicename may not be longer than 50 characters.' ) );
	}

	$user_nicename_check = $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->users WHERE user_nicename = %s AND user_login != %s LIMIT 1", $user_nicename, $user_login ) );

	if ( $user_nicename_check ) {
		$suffix = 2;
		while ( $user_nicename_check ) {
			// user_nicename allows 50 chars. Subtract one for a hyphen, plus the length of the suffix.
			$base_length         = 49 - mb_strlen( $suffix );
			$alt_user_nicename   = mb_substr( $user_nicename, 0, $base_length ) . "-$suffix";
			$user_nicename_check = $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->users WHERE user_nicename = %s AND user_login != %s LIMIT 1", $alt_user_nicename, $user_login ) );
			++$suffix;
		}
		$user_nicename = $alt_user_nicename;
	}

	$raw_user_email = empty( $userdata['user_email'] ) ? '' : $userdata['user_email'];

	/**
	 * Filters a user's email before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $raw_user_email The user's email.
	 */
	$user_email = apply_filters( 'pre_user_email', $raw_user_email );

	/*
	 * If there is no update, just check for `email_exists`. If there is an update,
	 * check if current email and new email are the same, and check `email_exists`
	 * accordingly.
	 */
	if ( ( ! $update || ( ! empty( $old_user_data ) && 0 !== strcasecmp( $user_email, $old_user_data->user_email ) ) )
		&& ! defined( 'WP_IMPORTING' )
		&& email_exists( $user_email )
	) {
		return new WP_Error( 'existing_user_email', __( 'Sorry, that email address is already used!' ) );
	}

	$raw_user_url = empty( $userdata['user_url'] ) ? '' : $userdata['user_url'];

	/**
	 * Filters a user's URL before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $raw_user_url The user's URL.
	 */
	$user_url = apply_filters( 'pre_user_url', $raw_user_url );

	if ( mb_strlen( $user_url ) > 100 ) {
		return new WP_Error( 'user_url_too_long', __( 'User URL may not be longer than 100 characters.' ) );
	}

	$user_registered = empty( $userdata['user_registered'] ) ? gmdate( 'Y-m-d H:i:s' ) : $userdata['user_registered'];

	$user_activation_key = empty( $userdata['user_activation_key'] ) ? '' : $userdata['user_activation_key'];

	if ( ! empty( $userdata['spam'] ) && ! is_multisite() ) {
		return new WP_Error( 'no_spam', __( 'Sorry, marking a user as spam is only supported on Multisite.' ) );
	}

	$spam = empty( $userdata['spam'] ) ? 0 : (bool) $userdata['spam'];

	// Store values to save in user meta.
	$meta = array();

	$nickname = empty( $userdata['nickname'] ) ? $user_login : $userdata['nickname'];

	/**
	 * Filters a user's nickname before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $nickname The user's nickname.
	 */
	$meta['nickname'] = apply_filters( 'pre_user_nickname', $nickname );

	$first_name = empty( $userdata['first_name'] ) ? '' : $userdata['first_name'];

	/**
	 * Filters a user's first name before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $first_name The user's first name.
	 */
	$meta['first_name'] = apply_filters( 'pre_user_first_name', $first_name );

	$last_name = empty( $userdata['last_name'] ) ? '' : $userdata['last_name'];

	/**
	 * Filters a user's last name before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $last_name The user's last name.
	 */
	$meta['last_name'] = apply_filters( 'pre_user_last_name', $last_name );

	if ( empty( $userdata['display_name'] ) ) {
		if ( $update ) {
			$display_name = $user_login;
		} elseif ( $meta['first_name'] && $meta['last_name'] ) {
			$display_name = sprintf(
				/* translators: 1: User's first name, 2: Last name. */
				_x( '%1$s %2$s', 'Display name based on first name and last name' ),
				$meta['first_name'],
				$meta['last_name']
			);
		} elseif ( $meta['first_name'] ) {
			$display_name = $meta['first_name'];
		} elseif ( $meta['last_name'] ) {
			$display_name = $meta['last_name'];
		} else {
			$display_name = $user_login;
		}
	} else {
		$display_name = $userdata['display_name'];
	}

	/**
	 * Filters a user's display name before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $display_name The user's display name.
	 */
	$display_name = apply_filters( 'pre_user_display_name', $display_name );

	$description = empty( $userdata['description'] ) ? '' : $userdata['description'];

	/**
	 * Filters a user's description before the user is created or updated.
	 *
	 * @since 2.0.3
	 *
	 * @param string $description The user's description.
	 */
	$meta['description'] = apply_filters( 'pre_user_description', $description );

	$meta['rich_editing'] = empty( $userdata['rich_editing'] ) ? 'true' : $userdata['rich_editing'];

	$meta['syntax_highlighting'] = empty( $userdata['syntax_highlighting'] ) ? 'true' : $userdata['syntax_highlighting'];

	$meta['comment_shortcuts'] = empty( $userdata['comment_shortcuts'] ) || 'false' === $userdata['comment_shortcuts'] ? 'false' : 'true';

	$admin_color         = empty( $userdata['admin_color'] ) ? 'fresh' : $userdata['admin_color'];
	$meta['admin_color'] = preg_replace( '|[^a-z0-9 _.\-@]|i', '', $admin_color );

	$meta['use_ssl'] = empty( $userdata['use_ssl'] ) ? 0 : (bool) $userdata['use_ssl'];

	$meta['show_admin_bar_front'] = empty( $userdata['show_admin_bar_front'] ) ? 'true' : $userdata['show_admin_bar_front'];

	$meta['locale'] = isset( $userdata['locale'] ) ? $userdata['locale'] : '';

	$compacted = compact( 'user_pass', 'user_nicename', 'user_email', 'user_url', 'user_registered', 'user_activation_key', 'display_name' );
	$data      = wp_unslash( $compacted );

	if ( ! $update ) {
		$data = $data + compact( 'user_login' );
	}

	if ( is_multisite() ) {
		$data = $data + compact( 'spam' );
	}

	/**
	 * Filters user data before the record is created or updated.
	 *
	 * It only includes data in the users table, not any user metadata.
	 *
	 * @since 4.9.0
	 * @since 5.8.0 The `$userdata` parameter was added.
	 *
	 * @param array    $data {
	 *     Values and keys for the user.
	 *
	 *     @type string $user_login      The user's login. Only included if $update == false
	 *     @type string $user_pass       The user's password.
	 *     @type string $user_email      The user's email.
	 *     @type string $user_url        The user's url.
	 *     @type string $user_nicename   The user's nice name. Defaults to a URL-safe version of user's login
	 *     @type string $display_name    The user's display name.
	 *     @type string $user_registered MySQL timestamp describing the moment when the user registered. Defaults to
	 *                                   the current UTC timestamp.
	 * }
	 * @param bool     $update   Whether the user is being updated rather than created.
	 * @param int|null $user_id  ID of the user to be updated, or NULL if the user is being created.
	 * @param array    $userdata The raw array of data passed to wp_insert_user().
	 */
	$data = apply_filters( 'wp_pre_insert_user_data', $data, $update, ( $update ? $user_id : null ), $userdata );

	if ( empty( $data ) || ! is_array( $data ) ) {
		return new WP_Error( 'empty_data', __( 'Not enough data to create this user.' ) );
	}

	if ( $update ) {
		if ( $user_email !== $old_user_data->user_email || $user_pass !== $old_user_data->user_pass ) {
			$data['user_activation_key'] = '';
		}
		$wpdb->update( $wpdb->users, $data, array( 'ID' => $user_id ) );
	} else {
		$wpdb->insert( $wpdb->users, $data );
		$user_id = (int) $wpdb->insert_id;
	}

	$user = new WP_User( $user_id );

	/**
	 * Filters a user's meta values and keys immediately after the user is created or updated
	 * and before any user meta is inserted or updated.
	 *
	 * Does not include contact methods. These are added using `wp_get_user_contact_methods( $user )`.
	 *
	 * For custom meta fields, see the {@see 'insert_custom_user_meta'} filter.
	 *
	 * @since 4.4.0
	 * @since 5.8.0 The `$userdata` parameter was added.
	 *
	 * @param array $meta {
	 *     Default meta values and keys for the user.
	 *
	 *     @type string   $nickname             The user's nickname. Default is the user's username.
	 *     @type string   $first_name           The user's first name.
	 *     @type string   $last_name            The user's last name.
	 *     @type string   $description          The user's description.
	 *     @type string   $rich_editing         Whether to enable the rich-editor for the user. Default 'true'.
	 *     @type string   $syntax_highlighting  Whether to enable the rich code editor for the user. Default 'true'.
	 *     @type string   $comment_shortcuts    Whether to enable keyboard shortcuts for the user. Default 'false'.
	 *     @type string   $admin_color          The color scheme for a user's admin screen. Default 'fresh'.
	 *     @type int|bool $use_ssl              Whether to force SSL on the user's admin area. 0|false if SSL
	 *                                          is not forced.
	 *     @type string   $show_admin_bar_front Whether to show the admin bar on the front end for the user.
	 *                                          Default 'true'.
	 *     @type string   $locale               User's locale. Default empty.
	 * }
	 * @param WP_User $user     User object.
	 * @param bool    $update   Whether the user is being updated rather than created.
	 * @param array   $userdata The raw array of data passed to wp_insert_user().
	 */
	$meta = apply_filters( 'insert_user_meta', $meta, $user, $update, $userdata );

	$custom_meta = array();
	if ( array_key_exists( 'meta_input', $userdata ) && is_array( $userdata['meta_input'] ) && ! empty( $userdata['meta_input'] ) ) {
		$custom_meta = $userdata['meta_input'];
	}

	/**
	 * Filters a user's custom meta values and keys immediately after the user is created or updated
	 * and before any user meta is inserted or updated.
	 *
	 * For non-custom meta fields, see the {@see 'insert_user_meta'} filter.
	 *
	 * @since 5.9.0
	 *
	 * @param array   $custom_meta Array of custom user meta values keyed by meta key.
	 * @param WP_User $user        User object.
	 * @param bool    $update      Whether the user is being updated rather than created.
	 * @param array   $userdata    The raw array of data passed to wp_insert_user().
	 */
	$custom_meta = apply_filters( 'insert_custom_user_meta', $custom_meta, $user, $update, $userdata );

	$meta = array_merge( $meta, $custom_meta );

	if ( $update ) {
		// Update user meta.
		foreach ( $meta as $key => $value ) {
			update_user_meta( $user_id, $key, $value );
		}
	} else {
		// Add user meta.
		foreach ( $meta as $key => $value ) {
			add_user_meta( $user_id, $key, $value );
		}
	}

	foreach ( wp_get_user_contact_methods( $user ) as $key => $value ) {
		if ( isset( $userdata[ $key ] ) ) {
			update_user_meta( $user_id, $key, $userdata[ $key ] );
		}
	}

	if ( isset( $userdata['role'] ) ) {
		$user->set_role( $userdata['role'] );
	} elseif ( ! $update ) {
		$user->set_role( get_option( 'default_role' ) );
	}

	clean_user_cache( $user_id );

	if ( $update ) {
		/**
		 * Fires immediately after an existing user is updated.
		 *
		 * @since 2.0.0
		 * @since 5.8.0 The `$userdata` parameter was added.
		 *
		 * @param int     $user_id       User ID.
		 * @param WP_User $old_user_data Object containing user's data prior to update.
		 * @param array   $userdata      The raw array of data passed to wp_insert_user().
		 */
		do_action( 'profile_update', $user_id, $old_user_data, $userdata );

		if ( isset( $userdata['spam'] ) && $userdata['spam'] != $old_user_data->spam ) {
			if ( 1 == $userdata['spam'] ) {
				/**
				 * Fires after the user is marked as a SPAM user.
				 *
				 * @since 3.0.0
				 *
				 * @param int $user_id ID of the user marked as SPAM.
				 */
				do_action( 'make_spam_user', $user_id );
			} else {
				/**
				 * Fires after the user is marked as a HAM user. Opposite of SPAM.
				 *
				 * @since 3.0.0
				 *
				 * @param int $user_id ID of the user marked as HAM.
				 */
				do_action( 'make_ham_user', $user_id );
			}
		}
	} else {
		/**
		 * Fires immediately after a new user is registered.
		 *
		 * @since 1.5.0
		 * @since 5.8.0 The `$userdata` parameter was added.
		 *
		 * @param int   $user_id  User ID.
		 * @param array $userdata The raw array of data passed to wp_insert_user().
		 */
		do_action( 'user_register', $user_id, $userdata );
	}

	return $user_id;
}

/**
 * Updates a user in the database.
 *
 * It is possible to update a user's password by specifying the 'user_pass'
 * value in the $userdata parameter array.
 *
 * If current user's password is being updated, then the cookies will be
 * cleared.
 *
 * @since 2.0.0
 *
 * @see wp_insert_user() For what fields can be set in $userdata.
 *
 * @param array|object|WP_User $userdata An array of user data or a user object of type stdClass or WP_User.
 * @return int|WP_Error The updated user's ID or a WP_Error object if the user could not be updated.
 */
function wp_update_user( $userdata ) {
	if ( $userdata instanceof stdClass ) {
		$userdata = get_object_vars( $userdata );
	} elseif ( $userdata instanceof WP_User ) {
		$userdata = $userdata->to_array();
	}

	$userdata_raw = $userdata;

	$user_id = isset( $userdata['ID'] ) ? (int) $userdata['ID'] : 0;
	if ( ! $user_id ) {
		return new WP_Error( 'invalid_user_id', __( 'Invalid user ID.' ) );
	}

	// First, get all of the original fields.
	$user_obj = get_userdata( $user_id );
	if ( ! $user_obj ) {
		return new WP_Error( 'invalid_user_id', __( 'Invalid user ID.' ) );
	}

	$user = $user_obj->to_array();

	// Add additional custom fields.
	foreach ( _get_additional_user_keys( $user_obj ) as $key ) {
		$user[ $key ] = get_user_meta( $user_id, $key, true );
	}

	// Escape data pulled from DB.
	$user = add_magic_quotes( $user );

	if ( ! empty( $userdata['user_pass'] ) && $userdata['user_pass'] !== $user_obj->user_pass ) {
		// If password is changing, hash it now.
		$plaintext_pass        = $userdata['user_pass'];
		$userdata['user_pass'] = wp_hash_password( $userdata['user_pass'] );

		/**
		 * Filters whether to send the password change email.
		 *
		 * @since 4.3.0
		 *
		 * @see wp_insert_user() For `$user` and `$userdata` fields.
		 *
		 * @param bool  $send     Whether to send the email.
		 * @param array $user     The original user array.
		 * @param array $userdata The updated user array.
		 */
		$send_password_change_email = apply_filters( 'send_password_change_email', true, $user, $userdata );
	}

	if ( isset( $userdata['user_email'] ) && $user['user_email'] !== $userdata['user_email'] ) {
		/**
		 * Filters whether to send the email change email.
		 *
		 * @since 4.3.0
		 *
		 * @see wp_insert_user() For `$user` and `$userdata` fields.
		 *
		 * @param bool  $send     Whether to send the email.
		 * @param array $user     The original user array.
		 * @param array $userdata The updated user array.
		 */
		$send_email_change_email = apply_filters( 'send_email_change_email', true, $user, $userdata );
	}

	clean_user_cache( $user_obj );

	// Merge old and new fields with new fields overwriting old ones.
	$userdata = array_merge( $user, $userdata );
	$user_id  = wp_insert_user( $userdata );

	if ( is_wp_error( $user_id ) ) {
		return $user_id;
	}

	$blog_name = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );

	$switched_locale = false;
	if ( ! empty( $send_password_change_email ) || ! empty( $send_email_change_email ) ) {
		$switched_locale = switch_to_user_locale( $user_id );
	}

	if ( ! empty( $send_password_change_email ) ) {
		/* translators: Do not translate USERNAME, ADMIN_EMAIL, EMAIL, SITENAME, SITEURL: those are placeholders. */
		$pass_change_text = __(
			'Hi ###USERNAME###,

This notice confirms that your password was changed on ###SITENAME###.

If you did not change your password, please contact the Site Administrator at
###ADMIN_EMAIL###

This email has been sent to ###EMAIL###

Regards,
All at ###SITENAME###
###SITEURL###'
		);

		$pass_change_email = array(
			'to'      => $user['user_email'],
			/* translators: Password change notification email subject. %s: Site title. */
			'subject' => __( '[%s] Password Changed' ),
			'message' => $pass_change_text,
			'headers' => '',
		);

		/**
		 * Filters the contents of the email sent when the user's password is changed.
		 *
		 * @since 4.3.0
		 *
		 * @param array $pass_change_email {
		 *     Used to build wp_mail().
		 *
		 *     @type string $to      The intended recipients. Add emails in a comma separated string.
		 *     @type string $subject The subject of the email.
		 *     @type string $message The content of the email.
		 *         The following strings have a special meaning and will get replaced dynamically:
		 *         - ###USERNAME###    The current user's username.
		 *         - ###ADMIN_EMAIL### The admin email in case this was unexpected.
		 *         - ###EMAIL###       The user's email address.
		 *         - ###SITENAME###    The name of the site.
		 *         - ###SITEURL###     The URL to the site.
		 *     @type string $headers Headers. Add headers in a newline (\r\n) separated string.
		 * }
		 * @param array $user     The original user array.
		 * @param array $userdata The updated user array.
		 */
		$pass_change_email = apply_filters( 'password_change_email', $pass_change_email, $user, $userdata );

		$pass_change_email['message'] = str_replace( '###USERNAME###', $user['user_login'], $pass_change_email['message'] );
		$pass_change_email['message'] = str_replace( '###ADMIN_EMAIL###', get_option( 'admin_email' ), $pass_change_email['message'] );
		$pass_change_email['message'] = str_replace( '###EMAIL###', $user['user_email'], $pass_change_email['message'] );
		$pass_change_email['message'] = str_replace( '###SITENAME###', $blog_name, $pass_change_email['message'] );
		$pass_change_email['message'] = str_replace( '###SITEURL###', home_url(), $pass_change_email['message'] );

		wp_mail( $pass_change_email['to'], sprintf( $pass_change_email['subject'], $blog_name ), $pass_change_email['message'], $pass_change_email['headers'] );
	}

	if ( ! empty( $send_email_change_email ) ) {
		/* translators: Do not translate USERNAME, ADMIN_EMAIL, NEW_EMAIL, EMAIL, SITENAME, SITEURL: those are placeholders. */
		$email_change_text = __(
			'Hi ###USERNAME###,

This notice confirms that your email address on ###SITENAME### was changed to ###NEW_EMAIL###.

If you did not change your email, please contact the Site Administrator at
###ADMIN_EMAIL###

This email has been sent to ###EMAIL###

Regards,
All at ###SITENAME###
###SITEURL###'
		);

		$email_change_email = array(
			'to'      => $user['user_email'],
			/* translators: Email change notification email subject. %s: Site title. */
			'subject' => __( '[%s] Email Changed' ),
			'message' => $email_change_text,
			'headers' => '',
		);

		/**
		 * Filters the contents of the email sent when the user's email is changed.
		 *
		 * @since 4.3.0
		 *
		 * @param array $email_change_email {
		 *     Used to build wp_mail().
		 *
		 *     @type string $to      The intended recipients.
		 *     @type string $subject The subject of the email.
		 *     @type string $message The content of the email.
		 *         The following strings have a special meaning and will get replaced dynamically:
		 *         - ###USERNAME###    The current user's username.
		 *         - ###ADMIN_EMAIL### The admin email in case this was unexpected.
		 *         - ###NEW_EMAIL###   The new email address.
		 *         - ###EMAIL###       The old email address.
		 *         - ###SITENAME###    The name of the site.
		 *         - ###SITEURL###     The URL to the site.
		 *     @type string $headers Headers.
		 * }
		 * @param array $user     The original user array.
		 * @param array $userdata The updated user array.
		 */
		$email_change_email = apply_filters( 'email_change_email', $email_change_email, $user, $userdata );

		$email_change_email['message'] = str_replace( '###USERNAME###', $user['user_login'], $email_change_email['message'] );
		$email_change_email['message'] = str_replace( '###ADMIN_EMAIL###', get_option( 'admin_email' ), $email_change_email['message'] );
		$email_change_email['message'] = str_replace( '###NEW_EMAIL###', $userdata['user_email'], $email_change_email['message'] );
		$email_change_email['message'] = str_replace( '###EMAIL###', $user['user_email'], $email_change_email['message'] );
		$email_change_email['message'] = str_replace( '###SITENAME###', $blog_name, $email_change_email['message'] );
		$email_change_email['message'] = str_replace( '###SITEURL###', home_url(), $email_change_email['message'] );

		wp_mail( $email_change_email['to'], sprintf( $email_change_email['subject'], $blog_name ), $email_change_email['message'], $email_change_email['headers'] );
	}

	if ( $switched_locale ) {
		restore_previous_locale();
	}

	// Update the cookies if the password changed.
	$current_user = wp_get_current_user();
	if ( $current_user->ID == $user_id ) {
		if ( isset( $plaintext_pass ) ) {
			wp_clear_auth_cookie();

			/*
			 * Here we calculate the expiration length of the current auth cookie and compare it to the default expiration.
			 * If it's greater than this, then we know the user checked 'Remember Me' when they logged in.
			 */
			$logged_in_cookie = wp_parse_auth_cookie( '', 'logged_in' );
			/** This filter is documented in wp-includes/pluggable.php */
			$default_cookie_life = apply_filters( 'auth_cookie_expiration', ( 2 * DAY_IN_SECONDS ), $user_id, false );
			$remember            = false;
			if ( false !== $logged_in_cookie && ( $logged_in_cookie['expiration'] - time() ) > $default_cookie_life ) {
				$remember = true;
			}

			wp_set_auth_cookie( $user_id, $remember );
		}
	}

	/**
	 * Fires after the user has been updated and emails have been sent.
	 *
	 * @since 6.3.0
	 *
	 * @param int   $user_id      The ID of the user that was just updated.
	 * @param array $userdata     The array of user data that was updated.
	 * @param array $userdata_raw The unedited array of user data that was updated.
	 */
	do_action( 'wp_update_user', $user_id, $userdata, $userdata_raw );

	return $user_id;
}

/**
 * Provides a simpler way of inserting a user into the database.
 *
 * Creates a new user with just the username, password, and email. For more
 * complex user creation use wp_insert_user() to specify more information.
 *
 * @since 2.0.0
 *
 * @see wp_insert_user() More complete way to create a new user.
 *
 * @param string $username The user's username.
 * @param string $password The user's password.
 * @param string $email    Optional. The user's email. Default empty.
 * @return int|WP_Error The newly created user's ID or a WP_Error object if the user could not
 *                      be created.
 */
function wp_create_user( $username, $password, $email = '' ) {
	$user_login = wp_slash( $username );
	$user_email = wp_slash( $email );
	$user_pass  = $password;

	$userdata = compact( 'user_login', 'user_email', 'user_pass' );
	return wp_insert_user( $userdata );
}

/**
 * Returns a list of meta keys to be (maybe) populated in wp_update_user().
 *
 * The list of keys returned via this function are dependent on the presence
 * of those keys in the user meta data to be set.
 *
 * @since 3.3.0
 * @access private
 *
 * @param WP_User $user WP_User instance.
 * @return string[] List of user keys to be populated in wp_update_user().
 */
function _get_additional_user_keys( $user ) {
	$keys = array( 'first_name', 'last_name', 'nickname', 'description', 'rich_editing', 'syntax_highlighting', 'comment_shortcuts', 'admin_color', 'use_ssl', 'show_admin_bar_front', 'locale' );
	return array_merge( $keys, array_keys( wp_get_user_contact_methods( $user ) ) );
}

/**
 * Sets up the user contact methods.
 *
 * Default contact methods were removed in 3.6. A filter dictates contact methods.
 *
 * @since 3.7.0
 *
 * @param WP_User|null $user Optional. WP_User object.
 * @return string[] Array of contact method labels keyed by contact method.
 */
function wp_get_user_contact_methods( $user = null ) {
	$methods = array();
	if ( get_site_option( 'initial_db_version' ) < 23588 ) {
		$methods = array(
			'aim'    => __( 'AIM' ),
			'yim'    => __( 'Yahoo IM' ),
			'jabber' => __( 'Jabber / Google Talk' ),
		);
	}

	/**
	 * Filters the user contact methods.
	 *
	 * @since 2.9.0
	 *
	 * @param string[]     $methods Array of contact method labels keyed by contact method.
	 * @param WP_User|null $user    WP_User object or null if none was provided.
	 */
	return apply_filters( 'user_contactmethods', $methods, $user );
}

/**
 * The old private function for setting up user contact methods.
 *
 * Use wp_get_user_contact_methods() instead.
 *
 * @since 2.9.0
 * @access private
 *
 * @param WP_User|null $user Optional. WP_User object. Default null.
 * @return string[] Array of contact method labels keyed by contact method.
 */
function _wp_get_user_contactmethods( $user = null ) {
	return wp_get_user_contact_methods( $user );
}

/**
 * Gets the text suggesting how to create strong passwords.
 *
 * @since 4.1.0
 *
 * @return string The password hint text.
 */
function wp_get_password_hint() {
	$hint = __( 'Hint: The password should be at least twelve characters long. To make it stronger, use upper and lower case letters, numbers, and symbols like ! " ? $ % ^ &amp; ).' );

	/**
	 * Filters the text describing the site's password complexity policy.
	 *
	 * @since 4.1.0
	 *
	 * @param string $hint The password hint text.
	 */
	return apply_filters( 'password_hint', $hint );
}

/**
 * Creates, stores, then returns a password reset key for user.
 *
 * @since 4.4.0
 *
 * @global PasswordHash $wp_hasher Portable PHP password hashing framework.
 *
 * @param WP_User $user User to retrieve password reset key for.
 * @return string|WP_Error Password reset key on success. WP_Error on error.
 */
function get_password_reset_key( $user ) {
	global $wp_hasher;

	if ( ! ( $user instanceof WP_User ) ) {
		return new WP_Error( 'invalidcombo', __( '<strong>Error:</strong> There is no account with that username or email address.' ) );
	}

	/**
	 * Fires before a new password is retrieved.
	 *
	 * Use the {@see 'retrieve_password'} hook instead.
	 *
	 * @since 1.5.0
	 * @deprecated 1.5.1 Misspelled. Use {@see 'retrieve_password'} hook instead.
	 *
	 * @param string $user_login The user login name.
	 */
	do_action_deprecated( 'retreive_password', array( $user->user_login ), '1.5.1', 'retrieve_password' );

	/**
	 * Fires before a new password is retrieved.
	 *
	 * @since 1.5.1
	 *
	 * @param string $user_login The user login name.
	 */
	do_action( 'retrieve_password', $user->user_login );

	$password_reset_allowed = wp_is_password_reset_allowed_for_user( $user );
	if ( ! $password_reset_allowed ) {
		return new WP_Error( 'no_password_reset', __( 'Password reset is not allowed for this user' ) );
	} elseif ( is_wp_error( $password_reset_allowed ) ) {
		return $password_reset_allowed;
	}

	// Generate something random for a password reset key.
	$key = wp_generate_password( 20, false );

	/**
	 * Fires when a password reset key is generated.
	 *
	 * @since 2.5.0
	 *
	 * @param string $user_login The username for the user.
	 * @param string $key        The generated password reset key.
	 */
	do_action( 'retrieve_password_key', $user->user_login, $key );

	// Now insert the key, hashed, into the DB.
	if ( empty( $wp_hasher ) ) {
		require_once ABSPATH . WPINC . '/class-phpass.php';
		$wp_hasher = new PasswordHash( 8, true );
	}

	$hashed = time() . ':' . $wp_hasher->HashPassword( $key );

	$key_saved = wp_update_user(
		array(
			'ID'                  => $user->ID,
			'user_activation_key' => $hashed,
		)
	);

	if ( is_wp_error( $key_saved ) ) {
		return $key_saved;
	}

	return $key;
}

/**
 * Retrieves a user row based on password reset key and login.
 *
 * A key is considered 'expired' if it exactly matches the value of the
 * user_activation_key field, rather than being matched after going through the
 * hashing process. This field is now hashed; old values are no longer accepted
 * but have a different WP_Error code so good user feedback can be provided.
 *
 * @since 3.1.0
 *
 * @global PasswordHash $wp_hasher Portable PHP password hashing framework instance.
 *
 * @param string $key       Hash to validate sending user's password.
 * @param string $login     The user login.
 * @return WP_User|WP_Error WP_User object on success, WP_Error object for invalid or expired keys.
 */
function check_password_reset_key( $key, $login ) {
	global $wp_hasher;

	$key = preg_replace( '/[^a-z0-9]/i', '', $key );

	if ( empty( $key ) || ! is_string( $key ) ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key.' ) );
	}

	if ( empty( $login ) || ! is_string( $login ) ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key.' ) );
	}

	$user = get_user_by( 'login', $login );

	if ( ! $user ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key.' ) );
	}

	if ( empty( $wp_hasher ) ) {
		require_once ABSPATH . WPINC . '/class-phpass.php';
		$wp_hasher = new PasswordHash( 8, true );
	}

	/**
	 * Filters the expiration time of password reset keys.
	 *
	 * @since 4.3.0
	 *
	 * @param int $expiration The expiration time in seconds.
	 */
	$expiration_duration = apply_filters( 'password_reset_expiration', DAY_IN_SECONDS );

	if ( str_contains( $user->user_activation_key, ':' ) ) {
		list( $pass_request_time, $pass_key ) = explode( ':', $user->user_activation_key, 2 );
		$expiration_time                      = $pass_request_time + $expiration_duration;
	} else {
		$pass_key        = $user->user_activation_key;
		$expiration_time = false;
	}

	if ( ! $pass_key ) {
		return new WP_Error( 'invalid_key', __( 'Invalid key.' ) );
	}

	$hash_is_correct = $wp_hasher->CheckPassword( $key, $pass_key );

	if ( $hash_is_correct && $expiration_time && time() < $expiration_time ) {
		return $user;
	} elseif ( $hash_is_correct && $expiration_time ) {
		// Key has an expiration time that's passed.
		return new WP_Error( 'expired_key', __( 'Invalid key.' ) );
	}

	if ( hash_equals( $user->user_activation_key, $key ) || ( $hash_is_correct && ! $expiration_time ) ) {
		$return  = new WP_Error( 'expired_key', __( 'Invalid key.' ) );
		$user_id = $user->ID;

		/**
		 * Filters the return value of check_password_reset_key() when an
		 * old-style key is used.
		 *
		 * @since 3.7.0 Previously plain-text keys were stored in the database.
		 * @since 4.3.0 Previously key hashes were stored without an expiration time.
		 *
		 * @param WP_Error $return  A WP_Error object denoting an expired key.
		 *                          Return a WP_User object to validate the key.
		 * @param int      $user_id The matched user ID.
		 */
		return apply_filters( 'password_reset_key_expired', $return, $user_id );
	}

	return new WP_Error( 'invalid_key', __( 'Invalid key.' ) );
}

/**
 * Handles sending a password retrieval email to a user.
 *
 * @since 2.5.0
 * @since 5.7.0 Added `$user_login` parameter.
 *
 * @global wpdb         $wpdb       WordPress database abstraction object.
 * @global PasswordHash $wp_hasher  Portable PHP password hashing framework.
 *
 * @param string $user_login Optional. Username to send a password retrieval email for.
 *                           Defaults to `$_POST['user_login']` if not set.
 * @return true|WP_Error True when finished, WP_Error object on error.
 */
function retrieve_password( $user_login = null ) {
	$errors    = new WP_Error();
	$user_data = false;

	// Use the passed $user_login if available, otherwise use $_POST['user_login'].
	if ( ! $user_login && ! empty( $_POST['user_login'] ) ) {
		$user_login = $_POST['user_login'];
	}

	$user_login = trim( wp_unslash( $user_login ) );

	if ( empty( $user_login ) ) {
		$errors->add( 'empty_username', __( '<strong>Error:</strong> Please enter a username or email address.' ) );
	} elseif ( strpos( $user_login, '@' ) ) {
		$user_data = get_user_by( 'email', $user_login );

		if ( empty( $user_data ) ) {
			$user_data = get_user_by( 'login', $user_login );
		}

		if ( empty( $user_data ) ) {
			$errors->add( 'invalid_email', __( '<strong>Error:</strong> There is no account with that username or email address.' ) );
		}
	} else {
		$user_data = get_user_by( 'login', $user_login );
	}

	/**
	 * Filters the user data during a password reset request.
	 *
	 * Allows, for example, custom validation using data other than username or email address.
	 *
	 * @since 5.7.0
	 *
	 * @param WP_User|false $user_data WP_User object if found, false if the user does not exist.
	 * @param WP_Error      $errors    A WP_Error object containing any errors generated
	 *                                 by using invalid credentials.
	 */
	$user_data = apply_filters( 'lostpassword_user_data', $user_data, $errors );

	/**
	 * Fires before errors are returned from a password reset request.
	 *
	 * @since 2.1.0
	 * @since 4.4.0 Added the `$errors` parameter.
	 * @since 5.4.0 Added the `$user_data` parameter.
	 *
	 * @param WP_Error      $errors    A WP_Error object containing any errors generated
	 *                                 by using invalid credentials.
	 * @param WP_User|false $user_data WP_User object if found, false if the user does not exist.
	 */
	do_action( 'lostpassword_post', $errors, $user_data );

	/**
	 * Filters the errors encountered on a password reset request.
	 *
	 * The filtered WP_Error object may, for example, contain errors for an invalid
	 * username or email address. A WP_Error object should always be returned,
	 * but may or may not contain errors.
	 *
	 * If any errors are present in $errors, this will abort the password reset request.
	 *
	 * @since 5.5.0
	 *
	 * @param WP_Error      $errors    A WP_Error object containing any errors generated
	 *                                 by using invalid credentials.
	 * @param WP_User|false $user_data WP_User object if found, false if the user does not exist.
	 */
	$errors = apply_filters( 'lostpassword_errors', $errors, $user_data );

	if ( $errors->has_errors() ) {
		return $errors;
	}

	if ( ! $user_data ) {
		$errors->add( 'invalidcombo', __( '<strong>Error:</strong> There is no account with that username or email address.' ) );
		return $errors;
	}

	/**
	 * Filters whether to send the retrieve password email.
	 *
	 * Return false to disable sending the email.
	 *
	 * @since 6.0.0
	 *
	 * @param bool    $send       Whether to send the email.
	 * @param string  $user_login The username for the user.
	 * @param WP_User $user_data  WP_User object.
	 */
	if ( ! apply_filters( 'send_retrieve_password_email', true, $user_login, $user_data ) ) {
		return true;
	}

	// Redefining user_login ensures we return the right case in the email.
	$user_login = $user_data->user_login;
	$user_email = $user_data->user_email;
	$key        = get_password_reset_key( $user_data );

	if ( is_wp_error( $key ) ) {
		return $key;
	}

	// Localize password reset message content for user.
	$locale = get_user_locale( $user_data );

	$switched_locale = switch_to_user_locale( $user_data->ID );

	if ( is_multisite() ) {
		$site_name = get_network()->site_name;
	} else {
		/*
		 * The blogname option is escaped with esc_html on the way into the database
		 * in sanitize_option. We want to reverse this for the plain text arena of emails.
		 */
		$site_name = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );
	}

	$message = __( 'Someone has requested a password reset for the following account:' ) . "\r\n\r\n";
	/* translators: %s: Site name. */
	$message .= sprintf( __( 'Site Name: %s' ), $site_name ) . "\r\n\r\n";
	/* translators: %s: User login. */
	$message .= sprintf( __( 'Username: %s' ), $user_login ) . "\r\n\r\n";
	$message .= __( 'If this was a mistake, ignore this email and nothing will happen.' ) . "\r\n\r\n";
	$message .= __( 'To reset your password, visit the following address:' ) . "\r\n\r\n";
	$message .= network_site_url( "wp-login.php?action=rp&key=$key&login=" . rawurlencode( $user_login ), 'login' ) . '&wp_lang=' . $locale . "\r\n\r\n";

	if ( ! is_user_logged_in() ) {
		$requester_ip = $_SERVER['REMOTE_ADDR'];
		if ( $requester_ip ) {
			$message .= sprintf(
				/* translators: %s: IP address of password reset requester. */
				__( 'This password reset request originated from the IP address %s.' ),
				$requester_ip
			) . "\r\n";
		}
	}

	/* translators: Password reset notification email subject. %s: Site title. */
	$title = sprintf( __( '[%s] Password Reset' ), $site_name );

	/**
	 * Filters the subject of the password reset email.
	 *
	 * @since 2.8.0
	 * @since 4.4.0 Added the `$user_login` and `$user_data` parameters.
	 *
	 * @param string  $title      Email subject.
	 * @param string  $user_login The username for the user.
	 * @param WP_User $user_data  WP_User object.
	 */
	$title = apply_filters( 'retrieve_password_title', $title, $user_login, $user_data );

	/**
	 * Filters the message body of the password reset mail.
	 *
	 * If the filtered message is empty, the password reset email will not be sent.
	 *
	 * @since 2.8.0
	 * @since 4.1.0 Added `$user_login` and `$user_data` parameters.
	 *
	 * @param string  $message    Email message.
	 * @param string  $key        The activation key.
	 * @param string  $user_login The username for the user.
	 * @param WP_User $user_data  WP_User object.
	 */
	$message = apply_filters( 'retrieve_password_message', $message, $key, $user_login, $user_data );

	// Short-circuit on falsey $message value for backwards compatibility.
	if ( ! $message ) {
		return true;
	}

	/*
	 * Wrap the single notification email arguments in an array
	 * to pass them to the retrieve_password_notification_email filter.
	 */
	$defaults = array(
		'to'      => $user_email,
		'subject' => $title,
		'message' => $message,
		'headers' => '',
	);

	/**
	 * Filters the contents of the reset password notification email sent to the user.
	 *
	 * @since 6.0.0
	 *
	 * @param array $defaults {
	 *     The default notification email arguments. Used to build wp_mail().
	 *
	 *     @type string $to      The intended recipient - user email address.
	 *     @type string $subject The subject of the email.
	 *     @type string $message The body of the email.
	 *     @type string $headers The headers of the email.
	 * }
	 * @type string  $key        The activation key.
	 * @type string  $user_login The username for the user.
	 * @type WP_User $user_data  WP_User object.
	 */
	$notification_email = apply_filters( 'retrieve_password_notification_email', $defaults, $key, $user_login, $user_data );

	if ( $switched_locale ) {
		restore_previous_locale();
	}

	if ( is_array( $notification_email ) ) {
		// Force key order and merge defaults in case any value is missing in the filtered array.
		$notification_email = array_merge( $defaults, $notification_email );
	} else {
		$notification_email = $defaults;
	}

	list( $to, $subject, $message, $headers ) = array_values( $notification_email );

	$subject = wp_specialchars_decode( $subject );

	if ( ! wp_mail( $to, $subject, $message, $headers ) ) {
		$errors->add(
			'retrieve_password_email_failure',
			sprintf(
				/* translators: %s: Documentation URL. */
				__( '<strong>Error:</strong> The email could not be sent. Your site may not be correctly configured to send emails. <a href="%s">Get support for resetting your password</a>.' ),
				esc_url( __( 'https://wordpress.org/documentation/article/reset-your-password/' ) )
			)
		);
		return $errors;
	}

	return true;
}

/**
 * Handles resetting the user's password.
 *
 * @since 2.5.0
 *
 * @param WP_User $user     The user
 * @param string  $new_pass New password for the user in plaintext
 */
function reset_password( $user, $new_pass ) {
	/**
	 * Fires before the user's password is reset.
	 *
	 * @since 1.5.0
	 *
	 * @param WP_User $user     The user.
	 * @param string  $new_pass New user password.
	 */
	do_action( 'password_reset', $user, $new_pass );

	wp_set_password( $new_pass, $user->ID );
	update_user_meta( $user->ID, 'default_password_nag', false );

	/**
	 * Fires after the user's password is reset.
	 *
	 * @since 4.4.0
	 *
	 * @param WP_User $user     The user.
	 * @param string  $new_pass New user password.
	 */
	do_action( 'after_password_reset', $user, $new_pass );
}

/**
 * Handles registering a new user.
 *
 * @since 2.5.0
 *
 * @param string $user_login User's username for logging in
 * @param string $user_email User's email address to send password and add
 * @return int|WP_Error Either user's ID or error on failure.
 */
function register_new_user( $user_login, $user_email ) {
	$errors = new WP_Error();

	$sanitized_user_login = sanitize_user( $user_login );
	/**
	 * Filters the email address of a user being registered.
	 *
	 * @since 2.1.0
	 *
	 * @param string $user_email The email address of the new user.
	 */
	$user_email = apply_filters( 'user_registration_email', $user_email );

	// Check the username.
	if ( '' === $sanitized_user_login ) {
		$errors->add( 'empty_username', __( '<strong>Error:</strong> Please enter a username.' ) );
	} elseif ( ! validate_username( $user_login ) ) {
		$errors->add( 'invalid_username', __( '<strong>Error:</strong> This username is invalid because it uses illegal characters. Please enter a valid username.' ) );
		$sanitized_user_login = '';
	} elseif ( username_exists( $sanitized_user_login ) ) {
		$errors->add( 'username_exists', __( '<strong>Error:</strong> This username is already registered. Please choose another one.' ) );
	} else {
		/** This filter is documented in wp-includes/user.php */
		$illegal_user_logins = (array) apply_filters( 'illegal_user_logins', array() );
		if ( in_array( strtolower( $sanitized_user_login ), array_map( 'strtolower', $illegal_user_logins ), true ) ) {
			$errors->add( 'invalid_username', __( '<strong>Error:</strong> Sorry, that username is not allowed.' ) );
		}
	}

	// Check the email address.
	if ( '' === $user_email ) {
		$errors->add( 'empty_email', __( '<strong>Error:</strong> Please type your email address.' ) );
	} elseif ( ! is_email( $user_email ) ) {
		$errors->add( 'invalid_email', __( '<strong>Error:</strong> The email address is not correct.' ) );
		$user_email = '';
	} elseif ( email_exists( $user_email ) ) {
		$errors->add(
			'email_exists',
			sprintf(
				/* translators: %s: Link to the login page. */
				__( '<strong>Error:</strong> This email address is already registered. <a href="%s">Log in</a> with this address or choose another one.' ),
				wp_login_url()
			)
		);
	}

	/**
	 * Fires when submitting registration form data, before the user is created.
	 *
	 * @since 2.1.0
	 *
	 * @param string   $sanitized_user_login The submitted username after being sanitized.
	 * @param string   $user_email           The submitted email.
	 * @param WP_Error $errors               Contains any errors with submitted username and email,
	 *                                       e.g., an empty field, an invalid username or email,
	 *                                       or an existing username or email.
	 */
	do_action( 'register_post', $sanitized_user_login, $user_email, $errors );

	/**
	 * Filters the errors encountered when a new user is being registered.
	 *
	 * The filtered WP_Error object may, for example, contain errors for an invalid
	 * or existing username or email address. A WP_Error object should always be returned,
	 * but may or may not contain errors.
	 *
	 * If any errors are present in $errors, this will abort the user's registration.
	 *
	 * @since 2.1.0
	 *
	 * @param WP_Error $errors               A WP_Error object containing any errors encountered
	 *                                       during registration.
	 * @param string   $sanitized_user_login User's username after it has been sanitized.
	 * @param string   $user_email           User's email.
	 */
	$errors = apply_filters( 'registration_errors', $errors, $sanitized_user_login, $user_email );

	if ( $errors->has_errors() ) {
		return $errors;
	}

	$user_pass = wp_generate_password( 12, false );
	$user_id   = wp_create_user( $sanitized_user_login, $user_pass, $user_email );
	if ( ! $user_id || is_wp_error( $user_id ) ) {
		$errors->add(
			'registerfail',
			sprintf(
				/* translators: %s: Admin email address. */
				__( '<strong>Error:</strong> Could not register you&hellip; please contact the <a href="mailto:%s">site admin</a>!' ),
				get_option( 'admin_email' )
			)
		);
		return $errors;
	}

	update_user_meta( $user_id, 'default_password_nag', true ); // Set up the password change nag.

	if ( ! empty( $_COOKIE['wp_lang'] ) ) {
		$wp_lang = sanitize_text_field( $_COOKIE['wp_lang'] );
		if ( in_array( $wp_lang, get_available_languages(), true ) ) {
			update_user_meta( $user_id, 'locale', $wp_lang ); // Set user locale if defined on registration.
		}
	}

	/**
	 * Fires after a new user registration has been recorded.
	 *
	 * @since 4.4.0
	 *
	 * @param int $user_id ID of the newly registered user.
	 */
	do_action( 'register_new_user', $user_id );

	return $user_id;
}

/**
 * Initiates email notifications related to the creation of new users.
 *
 * Notifications are sent both to the site admin and to the newly created user.
 *
 * @since 4.4.0
 * @since 4.6.0 Converted the `$notify` parameter to accept 'user' for sending
 *              notifications only to the user created.
 *
 * @param int    $user_id ID of the newly created user.
 * @param string $notify  Optional. Type of notification that should happen. Accepts 'admin'
 *                        or an empty string (admin only), 'user', or 'both' (admin and user).
 *                        Default 'both'.
 */
function wp_send_new_user_notifications( $user_id, $notify = 'both' ) {
	wp_new_user_notification( $user_id, null, $notify );
}

/**
 * Retrieves the current session token from the logged_in cookie.
 *
 * @since 4.0.0
 *
 * @return string Token.
 */
function wp_get_session_token() {
	$cookie = wp_parse_auth_cookie( '', 'logged_in' );
	return ! empty( $cookie['token'] ) ? $cookie['token'] : '';
}

/**
 * Retrieves a list of sessions for the current user.
 *
 * @since 4.0.0
 *
 * @return array Array of sessions.
 */
function wp_get_all_sessions() {
	$manager = WP_Session_Tokens::get_instance( get_current_user_id() );
	return $manager->get_all();
}

/**
 * Removes the current session token from the database.
 *
 * @since 4.0.0
 */
function wp_destroy_current_session() {
	$token = wp_get_session_token();
	if ( $token ) {
		$manager = WP_Session_Tokens::get_instance( get_current_user_id() );
		$manager->destroy( $token );
	}
}

/**
 * Removes all but the current session token for the current user for the database.
 *
 * @since 4.0.0
 */
function wp_destroy_other_sessions() {
	$token = wp_get_session_token();
	if ( $token ) {
		$manager = WP_Session_Tokens::get_instance( get_current_user_id() );
		$manager->destroy_others( $token );
	}
}

/**
 * Removes all session tokens for the current user from the database.
 *
 * @since 4.0.0
 */
function wp_destroy_all_sessions() {
	$manager = WP_Session_Tokens::get_instance( get_current_user_id() );
	$manager->destroy_all();
}

/**
 * Gets the user IDs of all users with no role on this site.
 *
 * @since 4.4.0
 * @since 4.9.0 The `$site_id` parameter was added to support multisite.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int|null $site_id Optional. The site ID to get users with no role for. Defaults to the current site.
 * @return string[] Array of user IDs as strings.
 */
function wp_get_users_with_no_role( $site_id = null ) {
	global $wpdb;

	if ( ! $site_id ) {
		$site_id = get_current_blog_id();
	}

	$prefix = $wpdb->get_blog_prefix( $site_id );

	if ( is_multisite() && get_current_blog_id() != $site_id ) {
		switch_to_blog( $site_id );
		$role_names = wp_roles()->get_names();
		restore_current_blog();
	} else {
		$role_names = wp_roles()->get_names();
	}

	$regex = implode( '|', array_keys( $role_names ) );
	$regex = preg_replace( '/[^a-zA-Z_\|-]/', '', $regex );
	$users = $wpdb->get_col(
		$wpdb->prepare(
			"SELECT user_id
			FROM $wpdb->usermeta
			WHERE meta_key = '{$prefix}capabilities'
			AND meta_value NOT REGEXP %s",
			$regex
		)
	);

	return $users;
}

/**
 * Retrieves the current user object.
 *
 * Will set the current user, if the current user is not set. The current user
 * will be set to the logged-in person. If no user is logged-in, then it will
 * set the current user to 0, which is invalid and won't have any permissions.
 *
 * This function is used by the pluggable functions wp_get_current_user() and
 * get_currentuserinfo(), the latter of which is deprecated but used for backward
 * compatibility.
 *
 * @since 4.5.0
 * @access private
 *
 * @see wp_get_current_user()
 * @global WP_User $current_user Checks if the current user is set.
 *
 * @return WP_User Current WP_User instance.
 */
function _wp_get_current_user() {
	global $current_user;

	if ( ! empty( $current_user ) ) {
		if ( $current_user instanceof WP_User ) {
			return $current_user;
		}

		// Upgrade stdClass to WP_User.
		if ( is_object( $current_user ) && isset( $current_user->ID ) ) {
			$cur_id       = $current_user->ID;
			$current_user = null;
			wp_set_current_user( $cur_id );
			return $current_user;
		}

		// $current_user has a junk value. Force to WP_User with ID 0.
		$current_user = null;
		wp_set_current_user( 0 );
		return $current_user;
	}

	if ( defined( 'XMLRPC_REQUEST' ) && XMLRPC_REQUEST ) {
		wp_set_current_user( 0 );
		return $current_user;
	}

	/**
	 * Filters the current user.
	 *
	 * The default filters use this to determine the current user from the
	 * request's cookies, if available.
	 *
	 * Returning a value of false will effectively short-circuit setting
	 * the current user.
	 *
	 * @since 3.9.0
	 *
	 * @param int|false $user_id User ID if one has been determined, false otherwise.
	 */
	$user_id = apply_filters( 'determine_current_user', false );
	if ( ! $user_id ) {
		wp_set_current_user( 0 );
		return $current_user;
	}

	wp_set_current_user( $user_id );

	return $current_user;
}

/**
 * Sends a confirmation request email when a change of user email address is attempted.
 *
 * @since 3.0.0
 * @since 4.9.0 This function was moved from wp-admin/includes/ms.php so it's no longer Multisite specific.
 *
 * @global WP_Error $errors WP_Error object.
 */
function send_confirmation_on_profile_email() {
	global $errors;

	$current_user = wp_get_current_user();
	if ( ! is_object( $errors ) ) {
		$errors = new WP_Error();
	}

	if ( $current_user->ID != $_POST['user_id'] ) {
		return false;
	}

	if ( $current_user->user_email != $_POST['email'] ) {
		if ( ! is_email( $_POST['email'] ) ) {
			$errors->add(
				'user_email',
				__( '<strong>Error:</strong> The email address is not correct.' ),
				array(
					'form-field' => 'email',
				)
			);

			return;
		}

		if ( email_exists( $_POST['email'] ) ) {
			$errors->add(
				'user_email',
				__( '<strong>Error:</strong> The email address is already used.' ),
				array(
					'form-field' => 'email',
				)
			);
			delete_user_meta( $current_user->ID, '_new_email' );

			return;
		}

		$hash           = md5( $_POST['email'] . time() . wp_rand() );
		$new_user_email = array(
			'hash'     => $hash,
			'newemail' => $_POST['email'],
		);
		update_user_meta( $current_user->ID, '_new_email', $new_user_email );

		$sitename = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );

		/* translators: Do not translate USERNAME, ADMIN_URL, EMAIL, SITENAME, SITEURL: those are placeholders. */
		$email_text = __(
			'Howdy ###USERNAME###,

You recently requested to have the email address on your account changed.

If this is correct, please click on the following link to change it:
###ADMIN_URL###

You can safely ignore and delete this email if you do not want to
take this action.

This email has been sent to ###EMAIL###

Regards,
All at ###SITENAME###
###SITEURL###'
		);

		/**
		 * Filters the text of the email sent when a change of user email address is attempted.
		 *
		 * The following strings have a special meaning and will get replaced dynamically:
		 * - ###USERNAME###  The current user's username.
		 * - ###ADMIN_URL### The link to click on to confirm the email change.
		 * - ###EMAIL###     The new email.
		 * - ###SITENAME###  The name of the site.
		 * - ###SITEURL###   The URL to the site.
		 *
		 * @since MU (3.0.0)
		 * @since 4.9.0 This filter is no longer Multisite specific.
		 *
		 * @param string $email_text     Text in the email.
		 * @param array  $new_user_email {
		 *     Data relating to the new user email address.
		 *
		 *     @type string $hash     The secure hash used in the confirmation link URL.
		 *     @type string $newemail The proposed new email address.
		 * }
		 */
		$content = apply_filters( 'new_user_email_content', $email_text, $new_user_email );

		$content = str_replace( '###USERNAME###', $current_user->user_login, $content );
		$content = str_replace( '###ADMIN_URL###', esc_url( self_admin_url( 'profile.php?newuseremail=' . $hash ) ), $content );
		$content = str_replace( '###EMAIL###', $_POST['email'], $content );
		$content = str_replace( '###SITENAME###', $sitename, $content );
		$content = str_replace( '###SITEURL###', home_url(), $content );

		/* translators: New email address notification email subject. %s: Site title. */
		wp_mail( $_POST['email'], sprintf( __( '[%s] Email Change Request' ), $sitename ), $content );

		$_POST['email'] = $current_user->user_email;
	}
}

/**
 * Adds an admin notice alerting the user to check for confirmation request email
 * after email address change.
 *
 * @since 3.0.0
 * @since 4.9.0 This function was moved from wp-admin/includes/ms.php so it's no longer Multisite specific.
 *
 * @global string $pagenow The filename of the current screen.
 */
function new_user_email_admin_notice() {
	global $pagenow;

	if ( 'profile.php' === $pagenow && isset( $_GET['updated'] ) ) {
		$email = get_user_meta( get_current_user_id(), '_new_email', true );
		if ( $email ) {
			$message = sprintf(
				/* translators: %s: New email address. */
				__( 'Your email address has not been updated yet. Please check your inbox at %s for a confirmation email.' ),
				'<code>' . esc_html( $email['newemail'] ) . '</code>'
			);
			wp_admin_notice( $message, array( 'type' => 'info' ) );
		}
	}
}

/**
 * Gets all personal data request types.
 *
 * @since 4.9.6
 * @access private
 *
 * @return string[] List of core privacy action types.
 */
function _wp_privacy_action_request_types() {
	return array(
		'export_personal_data',
		'remove_personal_data',
	);
}

/**
 * Registers the personal data exporter for users.
 *
 * @since 4.9.6
 *
 * @param array[] $exporters An array of personal data exporters.
 * @return array[] An array of personal data exporters.
 */
function wp_register_user_personal_data_exporter( $exporters ) {
	$exporters['wordpress-user'] = array(
		'exporter_friendly_name' => __( 'WordPress User' ),
		'callback'               => 'wp_user_personal_data_exporter',
	);

	return $exporters;
}

/**
 * Finds and exports personal data associated with an email address from the user and user_meta table.
 *
 * @since 4.9.6
 * @since 5.4.0 Added 'Community Events Location' group to the export data.
 * @since 5.4.0 Added 'Session Tokens' group to the export data.
 *
 * @param string $email_address  The user's email address.
 * @return array {
 *     An array of personal data.
 *
 *     @type array[] $data An array of personal data arrays.
 *     @type bool    $done Whether the exporter is finished.
 * }
 */
function wp_user_personal_data_exporter( $email_address ) {
	$email_address = trim( $email_address );

	$data_to_export = array();

	$user = get_user_by( 'email', $email_address );

	if ( ! $user ) {
		return array(
			'data' => array(),
			'done' => true,
		);
	}

	$user_meta = get_user_meta( $user->ID );

	$user_props_to_export = array(
		'ID'              => __( 'User ID' ),
		'user_login'      => __( 'User Login Name' ),
		'user_nicename'   => __( 'User Nice Name' ),
		'user_email'      => __( 'User Email' ),
		'user_url'        => __( 'User URL' ),
		'user_registered' => __( 'User Registration Date' ),
		'display_name'    => __( 'User Display Name' ),
		'nickname'        => __( 'User Nickname' ),
		'first_name'      => __( 'User First Name' ),
		'last_name'       => __( 'User Last Name' ),
		'description'     => __( 'User Description' ),
	);

	$user_data_to_export = array();

	foreach ( $user_props_to_export as $key => $name ) {
		$value = '';

		switch ( $key ) {
			case 'ID':
			case 'user_login':
			case 'user_nicename':
			case 'user_email':
			case 'user_url':
			case 'user_registered':
			case 'display_name':
				$value = $user->data->$key;
				break;
			case 'nickname':
			case 'first_name':
			case 'last_name':
			case 'description':
				$value = $user_meta[ $key ][0];
				break;
		}

		if ( ! empty( $value ) ) {
			$user_data_to_export[] = array(
				'name'  => $name,
				'value' => $value,
			);
		}
	}

	// Get the list of reserved names.
	$reserved_names = array_values( $user_props_to_export );

	/**
	 * Filters the user's profile data for the privacy exporter.
	 *
	 * @since 5.4.0
	 *
	 * @param array    $additional_user_profile_data {
	 *     An array of name-value pairs of additional user data items. Default empty array.
	 *
	 *     @type string $name  The user-facing name of an item name-value pair,e.g. 'IP Address'.
	 *     @type string $value The user-facing value of an item data pair, e.g. '50.60.70.0'.
	 * }
	 * @param WP_User  $user           The user whose data is being exported.
	 * @param string[] $reserved_names An array of reserved names. Any item in `$additional_user_data`
	 *                                 that uses one of these for its `name` will not be included in the export.
	 */
	$_extra_data = apply_filters( 'wp_privacy_additional_user_profile_data', array(), $user, $reserved_names );

	if ( is_array( $_extra_data ) && ! empty( $_extra_data ) ) {
		// Remove items that use reserved names.
		$extra_data = array_filter(
			$_extra_data,
			static function ( $item ) use ( $reserved_names ) {
				return ! in_array( $item['name'], $reserved_names, true );
			}
		);

		if ( count( $extra_data ) !== count( $_extra_data ) ) {
			_doing_it_wrong(
				__FUNCTION__,
				sprintf(
					/* translators: %s: wp_privacy_additional_user_profile_data */
					__( 'Filter %s returned items with reserved names.' ),
					'<code>wp_privacy_additional_user_profile_data</code>'
				),
				'5.4.0'
			);
		}

		if ( ! empty( $extra_data ) ) {
			$user_data_to_export = array_merge( $user_data_to_export, $extra_data );
		}
	}

	$data_to_export[] = array(
		'group_id'          => 'user',
		'group_label'       => __( 'User' ),
		'group_description' => __( 'User&#8217;s profile data.' ),
		'item_id'           => "user-{$user->ID}",
		'data'              => $user_data_to_export,
	);

	if ( isset( $user_meta['community-events-location'] ) ) {
		$location = maybe_unserialize( $user_meta['community-events-location'][0] );

		$location_props_to_export = array(
			'description' => __( 'City' ),
			'country'     => __( 'Country' ),
			'latitude'    => __( 'Latitude' ),
			'longitude'   => __( 'Longitude' ),
			'ip'          => __( 'IP' ),
		);

		$location_data_to_export = array();

		foreach ( $location_props_to_export as $key => $name ) {
			if ( ! empty( $location[ $key ] ) ) {
				$location_data_to_export[] = array(
					'name'  => $name,
					'value' => $location[ $key ],
				);
			}
		}

		$data_to_export[] = array(
			'group_id'          => 'community-events-location',
			'group_label'       => __( 'Community Events Location' ),
			'group_description' => __( 'User&#8217;s location data used for the Community Events in the WordPress Events and News dashboard widget.' ),
			'item_id'           => "community-events-location-{$user->ID}",
			'data'              => $location_data_to_export,
		);
	}

	if ( isset( $user_meta['session_tokens'] ) ) {
		$session_tokens = maybe_unserialize( $user_meta['session_tokens'][0] );

		$session_tokens_props_to_export = array(
			'expiration' => __( 'Expiration' ),
			'ip'         => __( 'IP' ),
			'ua'         => __( 'User Agent' ),
			'login'      => __( 'Last Login' ),
		);

		foreach ( $session_tokens as $token_key => $session_token ) {
			$session_tokens_data_to_export = array();

			foreach ( $session_tokens_props_to_export as $key => $name ) {
				if ( ! empty( $session_token[ $key ] ) ) {
					$value = $session_token[ $key ];
					if ( in_array( $key, array( 'expiration', 'login' ), true ) ) {
						$value = date_i18n( 'F d, Y H:i A', $value );
					}
					$session_tokens_data_to_export[] = array(
						'name'  => $name,
						'value' => $value,
					);
				}
			}

			$data_to_export[] = array(
				'group_id'          => 'session-tokens',
				'group_label'       => __( 'Session Tokens' ),
				'group_description' => __( 'User&#8217;s Session Tokens data.' ),
				'item_id'           => "session-tokens-{$user->ID}-{$token_key}",
				'data'              => $session_tokens_data_to_export,
			);
		}
	}

	return array(
		'data' => $data_to_export,
		'done' => true,
	);
}

/**
 * Updates log when privacy request is confirmed.
 *
 * @since 4.9.6
 * @access private
 *
 * @param int $request_id ID of the request.
 */
function _wp_privacy_account_request_confirmed( $request_id ) {
	$request = wp_get_user_request( $request_id );

	if ( ! $request ) {
		return;
	}

	if ( ! in_array( $request->status, array( 'request-pending', 'request-failed' ), true ) ) {
		return;
	}

	update_post_meta( $request_id, '_wp_user_request_confirmed_timestamp', time() );
	wp_update_post(
		array(
			'ID'          => $request_id,
			'post_status' => 'request-confirmed',
		)
	);
}

/**
 * Notifies the site administrator via email when a request is confirmed.
 *
 * Without this, the admin would have to manually check the site to see if any
 * action was needed on their part yet.
 *
 * @since 4.9.6
 *
 * @param int $request_id The ID of the request.
 */
function _wp_privacy_send_request_confirmation_notification( $request_id ) {
	$request = wp_get_user_request( $request_id );

	if ( ! ( $request instanceof WP_User_Request ) || 'request-confirmed' !== $request->status ) {
		return;
	}

	$already_notified = (bool) get_post_meta( $request_id, '_wp_admin_notified', true );

	if ( $already_notified ) {
		return;
	}

	if ( 'export_personal_data' === $request->action_name ) {
		$manage_url = admin_url( 'export-personal-data.php' );
	} elseif ( 'remove_personal_data' === $request->action_name ) {
		$manage_url = admin_url( 'erase-personal-data.php' );
	}
	$action_description = wp_user_request_action_description( $request->action_name );

	/**
	 * Filters the recipient of the data request confirmation notification.
	 *
	 * In a Multisite environment, this will default to the email address of the
	 * network admin because, by default, single site admins do not have the
	 * capabilities required to process requests. Some networks may wish to
	 * delegate those capabilities to a single-site admin, or a dedicated person
	 * responsible for managing privacy requests.
	 *
	 * @since 4.9.6
	 *
	 * @param string          $admin_email The email address of the notification recipient.
	 * @param WP_User_Request $request     The request that is initiating the notification.
	 */
	$admin_email = apply_filters( 'user_request_confirmed_email_to', get_site_option( 'admin_email' ), $request );

	$email_data = array(
		'request'     => $request,
		'user_email'  => $request->email,
		'description' => $action_description,
		'manage_url'  => $manage_url,
		'sitename'    => wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES ),
		'siteurl'     => home_url(),
		'admin_email' => $admin_email,
	);

	$subject = sprintf(
		/* translators: Privacy data request confirmed notification email subject. 1: Site title, 2: Name of the confirmed action. */
		__( '[%1$s] Action Confirmed: %2$s' ),
		$email_data['sitename'],
		$action_description
	);

	/**
	 * Filters the subject of the user request confirmation email.
	 *
	 * @since 4.9.8
	 *
	 * @param string $subject    The email subject.
	 * @param string $sitename   The name of the site.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $user_email  The email address confirming a request
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $manage_url  The link to click manage privacy requests of this type.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 *     @type string          $admin_email The administrator email receiving the mail.
	 * }
	 */
	$subject = apply_filters( 'user_request_confirmed_email_subject', $subject, $email_data['sitename'], $email_data );

	/* translators: Do not translate SITENAME, USER_EMAIL, DESCRIPTION, MANAGE_URL, SITEURL; those are placeholders. */
	$content = __(
		'Howdy,

A user data privacy request has been confirmed on ###SITENAME###:

User: ###USER_EMAIL###
Request: ###DESCRIPTION###

You can view and manage these data privacy requests here:

###MANAGE_URL###

Regards,
All at ###SITENAME###
###SITEURL###'
	);

	/**
	 * Filters the body of the user request confirmation email.
	 *
	 * The email is sent to an administrator when a user request is confirmed.
	 *
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###SITENAME###    The name of the site.
	 * ###USER_EMAIL###  The user email for the request.
	 * ###DESCRIPTION### Description of the action being performed so the user knows what the email is for.
	 * ###MANAGE_URL###  The URL to manage requests.
	 * ###SITEURL###     The URL to the site.
	 *
	 * @since 4.9.6
	 * @deprecated 5.8.0 Use {@see 'user_request_confirmed_email_content'} instead.
	 *                   For user erasure fulfillment email content
	 *                   use {@see 'user_erasure_fulfillment_email_content'} instead.
	 *
	 * @param string $content    The email content.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $user_email  The email address confirming a request
	 *     @type string          $description Description of the action being performed
	 *                                        so the user knows what the email is for.
	 *     @type string          $manage_url  The link to click manage privacy requests of this type.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 *     @type string          $admin_email The administrator email receiving the mail.
	 * }
	 */
	$content = apply_filters_deprecated(
		'user_confirmed_action_email_content',
		array( $content, $email_data ),
		'5.8.0',
		sprintf(
			/* translators: 1 & 2: Deprecation replacement options. */
			__( '%1$s or %2$s' ),
			'user_request_confirmed_email_content',
			'user_erasure_fulfillment_email_content'
		)
	);

	/**
	 * Filters the body of the user request confirmation email.
	 *
	 * The email is sent to an administrator when a user request is confirmed.
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###SITENAME###    The name of the site.
	 * ###USER_EMAIL###  The user email for the request.
	 * ###DESCRIPTION### Description of the action being performed so the user knows what the email is for.
	 * ###MANAGE_URL###  The URL to manage requests.
	 * ###SITEURL###     The URL to the site.
	 *
	 * @since 5.8.0
	 *
	 * @param string $content    The email content.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $user_email  The email address confirming a request
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $manage_url  The link to click manage privacy requests of this type.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 *     @type string          $admin_email The administrator email receiving the mail.
	 * }
	 */
	$content = apply_filters( 'user_request_confirmed_email_content', $content, $email_data );

	$content = str_replace( '###SITENAME###', $email_data['sitename'], $content );
	$content = str_replace( '###USER_EMAIL###', $email_data['user_email'], $content );
	$content = str_replace( '###DESCRIPTION###', $email_data['description'], $content );
	$content = str_replace( '###MANAGE_URL###', sanitize_url( $email_data['manage_url'] ), $content );
	$content = str_replace( '###SITEURL###', sanitize_url( $email_data['siteurl'] ), $content );

	$headers = '';

	/**
	 * Filters the headers of the user request confirmation email.
	 *
	 * @since 5.4.0
	 *
	 * @param string|array $headers    The email headers.
	 * @param string       $subject    The email subject.
	 * @param string       $content    The email content.
	 * @param int          $request_id The request ID.
	 * @param array        $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $user_email  The email address confirming a request
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $manage_url  The link to click manage privacy requests of this type.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 *     @type string          $admin_email The administrator email receiving the mail.
	 * }
	 */
	$headers = apply_filters( 'user_request_confirmed_email_headers', $headers, $subject, $content, $request_id, $email_data );

	$email_sent = wp_mail( $email_data['admin_email'], $subject, $content, $headers );

	if ( $email_sent ) {
		update_post_meta( $request_id, '_wp_admin_notified', true );
	}
}

/**
 * Notifies the user when their erasure request is fulfilled.
 *
 * Without this, the user would never know if their data was actually erased.
 *
 * @since 4.9.6
 *
 * @param int $request_id The privacy request post ID associated with this request.
 */
function _wp_privacy_send_erasure_fulfillment_notification( $request_id ) {
	$request = wp_get_user_request( $request_id );

	if ( ! ( $request instanceof WP_User_Request ) || 'request-completed' !== $request->status ) {
		return;
	}

	$already_notified = (bool) get_post_meta( $request_id, '_wp_user_notified', true );

	if ( $already_notified ) {
		return;
	}

	// Localize message content for user; fallback to site default for visitors.
	if ( ! empty( $request->user_id ) ) {
		$switched_locale = switch_to_user_locale( $request->user_id );
	} else {
		$switched_locale = switch_to_locale( get_locale() );
	}

	/**
	 * Filters the recipient of the data erasure fulfillment notification.
	 *
	 * @since 4.9.6
	 *
	 * @param string          $user_email The email address of the notification recipient.
	 * @param WP_User_Request $request    The request that is initiating the notification.
	 */
	$user_email = apply_filters( 'user_erasure_fulfillment_email_to', $request->email, $request );

	$email_data = array(
		'request'            => $request,
		'message_recipient'  => $user_email,
		'privacy_policy_url' => get_privacy_policy_url(),
		'sitename'           => wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES ),
		'siteurl'            => home_url(),
	);

	$subject = sprintf(
		/* translators: Erasure request fulfilled notification email subject. %s: Site title. */
		__( '[%s] Erasure Request Fulfilled' ),
		$email_data['sitename']
	);

	/**
	 * Filters the subject of the email sent when an erasure request is completed.
	 *
	 * @since 4.9.8
	 * @deprecated 5.8.0 Use {@see 'user_erasure_fulfillment_email_subject'} instead.
	 *
	 * @param string $subject    The email subject.
	 * @param string $sitename   The name of the site.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$subject = apply_filters_deprecated(
		'user_erasure_complete_email_subject',
		array( $subject, $email_data['sitename'], $email_data ),
		'5.8.0',
		'user_erasure_fulfillment_email_subject'
	);

	/**
	 * Filters the subject of the email sent when an erasure request is completed.
	 *
	 * @since 5.8.0
	 *
	 * @param string $subject    The email subject.
	 * @param string $sitename   The name of the site.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$subject = apply_filters( 'user_erasure_fulfillment_email_subject', $subject, $email_data['sitename'], $email_data );

	/* translators: Do not translate SITENAME, SITEURL; those are placeholders. */
	$content = __(
		'Howdy,

Your request to erase your personal data on ###SITENAME### has been completed.

If you have any follow-up questions or concerns, please contact the site administrator.

Regards,
All at ###SITENAME###
###SITEURL###'
	);

	if ( ! empty( $email_data['privacy_policy_url'] ) ) {
		/* translators: Do not translate SITENAME, SITEURL, PRIVACY_POLICY_URL; those are placeholders. */
		$content = __(
			'Howdy,

Your request to erase your personal data on ###SITENAME### has been completed.

If you have any follow-up questions or concerns, please contact the site administrator.

For more information, you can also read our privacy policy: ###PRIVACY_POLICY_URL###

Regards,
All at ###SITENAME###
###SITEURL###'
		);
	}

	/**
	 * Filters the body of the data erasure fulfillment notification.
	 *
	 * The email is sent to a user when their data erasure request is fulfilled
	 * by an administrator.
	 *
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###SITENAME###           The name of the site.
	 * ###PRIVACY_POLICY_URL### Privacy policy page URL.
	 * ###SITEURL###            The URL to the site.
	 *
	 * @since 4.9.6
	 * @deprecated 5.8.0 Use {@see 'user_erasure_fulfillment_email_content'} instead.
	 *                   For user request confirmation email content
	 *                   use {@see 'user_request_confirmed_email_content'} instead.
	 *
	 * @param string $content The email content.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$content = apply_filters_deprecated(
		'user_confirmed_action_email_content',
		array( $content, $email_data ),
		'5.8.0',
		sprintf(
			/* translators: 1 & 2: Deprecation replacement options. */
			__( '%1$s or %2$s' ),
			'user_erasure_fulfillment_email_content',
			'user_request_confirmed_email_content'
		)
	);

	/**
	 * Filters the body of the data erasure fulfillment notification.
	 *
	 * The email is sent to a user when their data erasure request is fulfilled
	 * by an administrator.
	 *
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###SITENAME###           The name of the site.
	 * ###PRIVACY_POLICY_URL### Privacy policy page URL.
	 * ###SITEURL###            The URL to the site.
	 *
	 * @since 5.8.0
	 *
	 * @param string $content The email content.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$content = apply_filters( 'user_erasure_fulfillment_email_content', $content, $email_data );

	$content = str_replace( '###SITENAME###', $email_data['sitename'], $content );
	$content = str_replace( '###PRIVACY_POLICY_URL###', $email_data['privacy_policy_url'], $content );
	$content = str_replace( '###SITEURL###', sanitize_url( $email_data['siteurl'] ), $content );

	$headers = '';

	/**
	 * Filters the headers of the data erasure fulfillment notification.
	 *
	 * @since 5.4.0
	 * @deprecated 5.8.0 Use {@see 'user_erasure_fulfillment_email_headers'} instead.
	 *
	 * @param string|array $headers    The email headers.
	 * @param string       $subject    The email subject.
	 * @param string       $content    The email content.
	 * @param int          $request_id The request ID.
	 * @param array        $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$headers = apply_filters_deprecated(
		'user_erasure_complete_email_headers',
		array( $headers, $subject, $content, $request_id, $email_data ),
		'5.8.0',
		'user_erasure_fulfillment_email_headers'
	);

	/**
	 * Filters the headers of the data erasure fulfillment notification.
	 *
	 * @since 5.8.0
	 *
	 * @param string|array $headers    The email headers.
	 * @param string       $subject    The email subject.
	 * @param string       $content    The email content.
	 * @param int          $request_id The request ID.
	 * @param array        $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request            User request object.
	 *     @type string          $message_recipient  The address that the email will be sent to. Defaults
	 *                                               to the value of `$request->email`, but can be changed
	 *                                               by the `user_erasure_fulfillment_email_to` filter.
	 *     @type string          $privacy_policy_url Privacy policy URL.
	 *     @type string          $sitename           The site name sending the mail.
	 *     @type string          $siteurl            The site URL sending the mail.
	 * }
	 */
	$headers = apply_filters( 'user_erasure_fulfillment_email_headers', $headers, $subject, $content, $request_id, $email_data );

	$email_sent = wp_mail( $user_email, $subject, $content, $headers );

	if ( $switched_locale ) {
		restore_previous_locale();
	}

	if ( $email_sent ) {
		update_post_meta( $request_id, '_wp_user_notified', true );
	}
}

/**
 * Returns request confirmation message HTML.
 *
 * @since 4.9.6
 * @access private
 *
 * @param int $request_id The request ID being confirmed.
 * @return string The confirmation message.
 */
function _wp_privacy_account_request_confirmed_message( $request_id ) {
	$request = wp_get_user_request( $request_id );

	$message  = '<p class="success">' . __( 'Action has been confirmed.' ) . '</p>';
	$message .= '<p>' . __( 'The site administrator has been notified and will fulfill your request as soon as possible.' ) . '</p>';

	if ( $request && in_array( $request->action_name, _wp_privacy_action_request_types(), true ) ) {
		if ( 'export_personal_data' === $request->action_name ) {
			$message  = '<p class="success">' . __( 'Thanks for confirming your export request.' ) . '</p>';
			$message .= '<p>' . __( 'The site administrator has been notified. You will receive a link to download your export via email when they fulfill your request.' ) . '</p>';
		} elseif ( 'remove_personal_data' === $request->action_name ) {
			$message  = '<p class="success">' . __( 'Thanks for confirming your erasure request.' ) . '</p>';
			$message .= '<p>' . __( 'The site administrator has been notified. You will receive an email confirmation when they erase your data.' ) . '</p>';
		}
	}

	/**
	 * Filters the message displayed to a user when they confirm a data request.
	 *
	 * @since 4.9.6
	 *
	 * @param string $message    The message to the user.
	 * @param int    $request_id The ID of the request being confirmed.
	 */
	$message = apply_filters( 'user_request_action_confirmed_message', $message, $request_id );

	return $message;
}

/**
 * Creates and logs a user request to perform a specific action.
 *
 * Requests are stored inside a post type named `user_request` since they can apply to both
 * users on the site, or guests without a user account.
 *
 * @since 4.9.6
 * @since 5.7.0 Added the `$status` parameter.
 *
 * @param string $email_address           User email address. This can be the address of a registered
 *                                        or non-registered user.
 * @param string $action_name             Name of the action that is being confirmed. Required.
 * @param array  $request_data            Misc data you want to send with the verification request and pass
 *                                        to the actions once the request is confirmed.
 * @param string $status                  Optional request status (pending or confirmed). Default 'pending'.
 * @return int|WP_Error                   Returns the request ID if successful, or a WP_Error object on failure.
 */
function wp_create_user_request( $email_address = '', $action_name = '', $request_data = array(), $status = 'pending' ) {
	$email_address = sanitize_email( $email_address );
	$action_name   = sanitize_key( $action_name );

	if ( ! is_email( $email_address ) ) {
		return new WP_Error( 'invalid_email', __( 'Invalid email address.' ) );
	}

	if ( ! in_array( $action_name, _wp_privacy_action_request_types(), true ) ) {
		return new WP_Error( 'invalid_action', __( 'Invalid action name.' ) );
	}

	if ( ! in_array( $status, array( 'pending', 'confirmed' ), true ) ) {
		return new WP_Error( 'invalid_status', __( 'Invalid request status.' ) );
	}

	$user    = get_user_by( 'email', $email_address );
	$user_id = $user && ! is_wp_error( $user ) ? $user->ID : 0;

	// Check for duplicates.
	$requests_query = new WP_Query(
		array(
			'post_type'     => 'user_request',
			'post_name__in' => array( $action_name ), // Action name stored in post_name column.
			'title'         => $email_address,        // Email address stored in post_title column.
			'post_status'   => array(
				'request-pending',
				'request-confirmed',
			),
			'fields'        => 'ids',
		)
	);

	if ( $requests_query->found_posts ) {
		return new WP_Error( 'duplicate_request', __( 'An incomplete personal data request for this email address already exists.' ) );
	}

	$request_id = wp_insert_post(
		array(
			'post_author'   => $user_id,
			'post_name'     => $action_name,
			'post_title'    => $email_address,
			'post_content'  => wp_json_encode( $request_data ),
			'post_status'   => 'request-' . $status,
			'post_type'     => 'user_request',
			'post_date'     => current_time( 'mysql', false ),
			'post_date_gmt' => current_time( 'mysql', true ),
		),
		true
	);

	return $request_id;
}

/**
 * Gets action description from the name and return a string.
 *
 * @since 4.9.6
 *
 * @param string $action_name Action name of the request.
 * @return string Human readable action name.
 */
function wp_user_request_action_description( $action_name ) {
	switch ( $action_name ) {
		case 'export_personal_data':
			$description = __( 'Export Personal Data' );
			break;
		case 'remove_personal_data':
			$description = __( 'Erase Personal Data' );
			break;
		default:
			/* translators: %s: Action name. */
			$description = sprintf( __( 'Confirm the "%s" action' ), $action_name );
			break;
	}

	/**
	 * Filters the user action description.
	 *
	 * @since 4.9.6
	 *
	 * @param string $description The default description.
	 * @param string $action_name The name of the request.
	 */
	return apply_filters( 'user_request_action_description', $description, $action_name );
}

/**
 * Send a confirmation request email to confirm an action.
 *
 * If the request is not already pending, it will be updated.
 *
 * @since 4.9.6
 *
 * @param string $request_id ID of the request created via wp_create_user_request().
 * @return true|WP_Error True on success, `WP_Error` on failure.
 */
function wp_send_user_request( $request_id ) {
	$request_id = absint( $request_id );
	$request    = wp_get_user_request( $request_id );

	if ( ! $request ) {
		return new WP_Error( 'invalid_request', __( 'Invalid personal data request.' ) );
	}

	// Localize message content for user; fallback to site default for visitors.
	if ( ! empty( $request->user_id ) ) {
		$switched_locale = switch_to_user_locale( $request->user_id );
	} else {
		$switched_locale = switch_to_locale( get_locale() );
	}

	$email_data = array(
		'request'     => $request,
		'email'       => $request->email,
		'description' => wp_user_request_action_description( $request->action_name ),
		'confirm_url' => add_query_arg(
			array(
				'action'      => 'confirmaction',
				'request_id'  => $request_id,
				'confirm_key' => wp_generate_user_request_key( $request_id ),
			),
			wp_login_url()
		),
		'sitename'    => wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES ),
		'siteurl'     => home_url(),
	);

	/* translators: Confirm privacy data request notification email subject. 1: Site title, 2: Name of the action. */
	$subject = sprintf( __( '[%1$s] Confirm Action: %2$s' ), $email_data['sitename'], $email_data['description'] );

	/**
	 * Filters the subject of the email sent when an account action is attempted.
	 *
	 * @since 4.9.6
	 *
	 * @param string $subject    The email subject.
	 * @param string $sitename   The name of the site.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $email       The email address this is being sent to.
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $confirm_url The link to click on to confirm the account action.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 * }
	 */
	$subject = apply_filters( 'user_request_action_email_subject', $subject, $email_data['sitename'], $email_data );

	/* translators: Do not translate DESCRIPTION, CONFIRM_URL, SITENAME, SITEURL: those are placeholders. */
	$content = __(
		'Howdy,

A request has been made to perform the following action on your account:

     ###DESCRIPTION###

To confirm this, please click on the following link:
###CONFIRM_URL###

You can safely ignore and delete this email if you do not want to
take this action.

Regards,
All at ###SITENAME###
###SITEURL###'
	);

	/**
	 * Filters the text of the email sent when an account action is attempted.
	 *
	 * The following strings have a special meaning and will get replaced dynamically:
	 *
	 * ###DESCRIPTION### Description of the action being performed so the user knows what the email is for.
	 * ###CONFIRM_URL### The link to click on to confirm the account action.
	 * ###SITENAME###    The name of the site.
	 * ###SITEURL###     The URL to the site.
	 *
	 * @since 4.9.6
	 *
	 * @param string $content Text in the email.
	 * @param array  $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $email       The email address this is being sent to.
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $confirm_url The link to click on to confirm the account action.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 * }
	 */
	$content = apply_filters( 'user_request_action_email_content', $content, $email_data );

	$content = str_replace( '###DESCRIPTION###', $email_data['description'], $content );
	$content = str_replace( '###CONFIRM_URL###', sanitize_url( $email_data['confirm_url'] ), $content );
	$content = str_replace( '###EMAIL###', $email_data['email'], $content );
	$content = str_replace( '###SITENAME###', $email_data['sitename'], $content );
	$content = str_replace( '###SITEURL###', sanitize_url( $email_data['siteurl'] ), $content );

	$headers = '';

	/**
	 * Filters the headers of the email sent when an account action is attempted.
	 *
	 * @since 5.4.0
	 *
	 * @param string|array $headers    The email headers.
	 * @param string       $subject    The email subject.
	 * @param string       $content    The email content.
	 * @param int          $request_id The request ID.
	 * @param array        $email_data {
	 *     Data relating to the account action email.
	 *
	 *     @type WP_User_Request $request     User request object.
	 *     @type string          $email       The email address this is being sent to.
	 *     @type string          $description Description of the action being performed so the user knows what the email is for.
	 *     @type string          $confirm_url The link to click on to confirm the account action.
	 *     @type string          $sitename    The site name sending the mail.
	 *     @type string          $siteurl     The site URL sending the mail.
	 * }
	 */
	$headers = apply_filters( 'user_request_action_email_headers', $headers, $subject, $content, $request_id, $email_data );

	$email_sent = wp_mail( $email_data['email'], $subject, $content, $headers );

	if ( $switched_locale ) {
		restore_previous_locale();
	}

	if ( ! $email_sent ) {
		return new WP_Error( 'privacy_email_error', __( 'Unable to send personal data export confirmation email.' ) );
	}

	return true;
}

/**
 * Returns a confirmation key for a user action and stores the hashed version for future comparison.
 *
 * @since 4.9.6
 *
 * @param int $request_id Request ID.
 * @return string Confirmation key.
 */
function wp_generate_user_request_key( $request_id ) {
	global $wp_hasher;

	// Generate something random for a confirmation key.
	$key = wp_generate_password( 20, false );

	// Return the key, hashed.
	if ( empty( $wp_hasher ) ) {
		require_once ABSPATH . WPINC . '/class-phpass.php';
		$wp_hasher = new PasswordHash( 8, true );
	}

	wp_update_post(
		array(
			'ID'            => $request_id,
			'post_status'   => 'request-pending',
			'post_password' => $wp_hasher->HashPassword( $key ),
		)
	);

	return $key;
}

/**
 * Validates a user request by comparing the key with the request's key.
 *
 * @since 4.9.6
 *
 * @param string $request_id ID of the request being confirmed.
 * @param string $key        Provided key to validate.
 * @return true|WP_Error True on success, WP_Error on failure.
 */
function wp_validate_user_request_key( $request_id, $key ) {
	global $wp_hasher;

	$request_id       = absint( $request_id );
	$request          = wp_get_user_request( $request_id );
	$saved_key        = $request->confirm_key;
	$key_request_time = $request->modified_timestamp;

	if ( ! $request || ! $saved_key || ! $key_request_time ) {
		return new WP_Error( 'invalid_request', __( 'Invalid personal data request.' ) );
	}

	if ( ! in_array( $request->status, array( 'request-pending', 'request-failed' ), true ) ) {
		return new WP_Error( 'expired_request', __( 'This personal data request has expired.' ) );
	}

	if ( empty( $key ) ) {
		return new WP_Error( 'missing_key', __( 'The confirmation key is missing from this personal data request.' ) );
	}

	if ( empty( $wp_hasher ) ) {
		require_once ABSPATH . WPINC . '/class-phpass.php';
		$wp_hasher = new PasswordHash( 8, true );
	}

	/**
	 * Filters the expiration time of confirm keys.
	 *
	 * @since 4.9.6
	 *
	 * @param int $expiration The expiration time in seconds.
	 */
	$expiration_duration = (int) apply_filters( 'user_request_key_expiration', DAY_IN_SECONDS );
	$expiration_time     = $key_request_time + $expiration_duration;

	if ( ! $wp_hasher->CheckPassword( $key, $saved_key ) ) {
		return new WP_Error( 'invalid_key', __( 'The confirmation key is invalid for this personal data request.' ) );
	}

	if ( ! $expiration_time || time() > $expiration_time ) {
		return new WP_Error( 'expired_key', __( 'The confirmation key has expired for this personal data request.' ) );
	}

	return true;
}

/**
 * Returns the user request object for the specified request ID.
 *
 * @since 4.9.6
 *
 * @param int $request_id The ID of the user request.
 * @return WP_User_Request|false
 */
function wp_get_user_request( $request_id ) {
	$request_id = absint( $request_id );
	$post       = get_post( $request_id );

	if ( ! $post || 'user_request' !== $post->post_type ) {
		return false;
	}

	return new WP_User_Request( $post );
}

/**
 * Checks if Application Passwords is supported.
 *
 * Application Passwords is supported only by sites using SSL or local environments
 * but may be made available using the {@see 'wp_is_application_passwords_available'} filter.
 *
 * @since 5.9.0
 *
 * @return bool
 */
function wp_is_application_passwords_supported() {
	return is_ssl() || 'local' === wp_get_environment_type();
}

/**
 * Checks if Application Passwords is globally available.
 *
 * By default, Application Passwords is available to all sites using SSL or to local environments.
 * Use the {@see 'wp_is_application_passwords_available'} filter to adjust its availability.
 *
 * @since 5.6.0
 *
 * @return bool
 */
function wp_is_application_passwords_available() {
	/**
	 * Filters whether Application Passwords is available.
	 *
	 * @since 5.6.0
	 *
	 * @param bool $available True if available, false otherwise.
	 */
	return apply_filters( 'wp_is_application_passwords_available', wp_is_application_passwords_supported() );
}

/**
 * Checks if Application Passwords is available for a specific user.
 *
 * By default all users can use Application Passwords. Use {@see 'wp_is_application_passwords_available_for_user'}
 * to restrict availability to certain users.
 *
 * @since 5.6.0
 *
 * @param int|WP_User $user The user to check.
 * @return bool
 */
function wp_is_application_passwords_available_for_user( $user ) {
	if ( ! wp_is_application_passwords_available() ) {
		return false;
	}

	if ( ! is_object( $user ) ) {
		$user = get_userdata( $user );
	}

	if ( ! $user || ! $user->exists() ) {
		return false;
	}

	/**
	 * Filters whether Application Passwords is available for a specific user.
	 *
	 * @since 5.6.0
	 *
	 * @param bool    $available True if available, false otherwise.
	 * @param WP_User $user      The user to check.
	 */
	return apply_filters( 'wp_is_application_passwords_available_for_user', true, $user );
}

/**
 * Registers the user meta property for persisted preferences.
 *
 * This property is used to store user preferences across page reloads and is
 * currently used by the block editor for preferences like 'fullscreenMode' and
 * 'fixedToolbar'.
 *
 * @since 6.1.0
 * @access private
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 */
function wp_register_persisted_preferences_meta() {
	/*
	 * Create a meta key that incorporates the blog prefix so that each site
	 * on a multisite can have distinct user preferences.
	 */
	global $wpdb;
	$meta_key = $wpdb->get_blog_prefix() . 'persisted_preferences';

	register_meta(
		'user',
		$meta_key,
		array(
			'type'         => 'object',
			'single'       => true,
			'show_in_rest' => array(
				'name'   => 'persisted_preferences',
				'type'   => 'object',
				'schema' => array(
					'type'                 => 'object',
					'context'              => array( 'edit' ),
					'properties'           => array(
						'_modified' => array(
							'description' => __( 'The date and time the preferences were updated.' ),
							'type'        => 'string',
							'format'      => 'date-time',
							'readonly'    => false,
						),
					),
					'additionalProperties' => true,
				),
			),
		)
	);
}

/**
 * Sets the last changed time for the 'users' cache group.
 *
 * @since 6.3.0
 */
function wp_cache_set_users_last_changed() {
	wp_cache_set_last_changed( 'users' );
}

/**
 * Checks if password reset is allowed for a specific user.
 *
 * @since 6.3.0
 *
 * @param int|WP_User $user The user to check.
 * @return bool|WP_Error True if allowed, false or WP_Error otherwise.
 */
function wp_is_password_reset_allowed_for_user( $user ) {
	if ( ! is_object( $user ) ) {
		$user = get_userdata( $user );
	}

	if ( ! $user || ! $user->exists() ) {
		return false;
	}
	$allow = true;
	if ( is_multisite() && is_user_spammy( $user ) ) {
		$allow = false;
	}

	/**
	 * Filters whether to allow a password to be reset.
	 *
	 * @since 2.7.0
	 *
	 * @param bool $allow   Whether to allow the password to be reset. Default true.
	 * @param int  $user_id The ID of the user attempting to reset a password.
	 */
	return apply_filters( 'allow_password_reset', $allow, $user->ID );
}
onomy object on success, WP_Error object on failure.
 */
function register_taxonomy( $taxonomy, $object_type, $args = array() ) {
	global $wp_taxonomies;

	if ( ! is_array( $wp_taxonomies ) ) {
		$wp_taxonomies = array();
	}

	$args = wp_parse_args( $args );

	if ( empty( $taxonomy ) || strlen( $taxonomy ) > 32 ) {
		_doing_it_wrong( __FUNCTION__, __( 'Taxonomy names must be between 1 and 32 characters in length.' ), '4.2.0' );
		return new WP_Error( 'taxonomy_length_invalid', __( 'Taxonomy names must be between 1 and 32 characters in length.' ) );
	}

	$taxonomy_object = new WP_Taxonomy( $taxonomy, $object_type, $args );
	$taxonomy_object->add_rewrite_rules();

	$wp_taxonomies[ $taxonomy ] = $taxonomy_object;

	$taxonomy_object->add_hooks();

	// Add default term.
	if ( ! empty( $taxonomy_object->default_term ) ) {
		$term = term_exists( $taxonomy_object->default_term['name'], $taxonomy );
		if ( $term ) {
			update_option( 'default_term_' . $taxonomy_object->name, $term['term_id'] );
		} else {
			$term = wp_insert_term(
				$taxonomy_object->default_term['name'],
				$taxonomy,
				array(
					'slug'        => sanitize_title( $taxonomy_object->default_term['slug'] ),
					'description' => $taxonomy_object->default_term['description'],
				)
			);

			// Update `term_id` in options.
			if ( ! is_wp_error( $term ) ) {
				update_option( 'default_term_' . $taxonomy_object->name, $term['term_id'] );
			}
		}
	}

	/**
	 * Fires after a taxonomy is registered.
	 *
	 * @since 3.3.0
	 *
	 * @param string       $taxonomy    Taxonomy slug.
	 * @param array|string $object_type Object type or array of object types.
	 * @param array        $args        Array of taxonomy registration arguments.
	 */
	do_action( 'registered_taxonomy', $taxonomy, $object_type, (array) $taxonomy_object );

	/**
	 * Fires after a specific taxonomy is registered.
	 *
	 * The dynamic portion of the filter name, `$taxonomy`, refers to the taxonomy key.
	 *
	 * Possible hook names include:
	 *
	 *  - `registered_taxonomy_category`
	 *  - `registered_taxonomy_post_tag`
	 *
	 * @since 6.0.0
	 *
	 * @param string       $taxonomy    Taxonomy slug.
	 * @param array|string $object_type Object type or array of object types.
	 * @param array        $args        Array of taxonomy registration arguments.
	 */
	do_action( "registered_taxonomy_{$taxonomy}", $taxonomy, $object_type, (array) $taxonomy_object );

	return $taxonomy_object;
}

/**
 * Unregisters a taxonomy.
 *
 * Can not be used to unregister built-in taxonomies.
 *
 * @since 4.5.0
 *
 * @global WP_Taxonomy[] $wp_taxonomies List of taxonomies.
 *
 * @param string $taxonomy Taxonomy name.
 * @return true|WP_Error True on success, WP_Error on failure or if the taxonomy doesn't exist.
 */
function unregister_taxonomy( $taxonomy ) {
	global $wp_taxonomies;

	if ( ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	$taxonomy_object = get_taxonomy( $taxonomy );

	// Do not allow unregistering internal taxonomies.
	if ( $taxonomy_object->_builtin ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Unregistering a built-in taxonomy is not allowed.' ) );
	}

	$taxonomy_object->remove_rewrite_rules();
	$taxonomy_object->remove_hooks();

	// Remove the taxonomy.
	unset( $wp_taxonomies[ $taxonomy ] );

	/**
	 * Fires after a taxonomy is unregistered.
	 *
	 * @since 4.5.0
	 *
	 * @param string $taxonomy Taxonomy name.
	 */
	do_action( 'unregistered_taxonomy', $taxonomy );

	return true;
}

/**
 * Builds an object with all taxonomy labels out of a taxonomy object.
 *
 * @since 3.0.0
 * @since 4.3.0 Added the `no_terms` label.
 * @since 4.4.0 Added the `items_list_navigation` and `items_list` labels.
 * @since 4.9.0 Added the `most_used` and `back_to_items` labels.
 * @since 5.7.0 Added the `filter_by_item` label.
 * @since 5.8.0 Added the `item_link` and `item_link_description` labels.
 * @since 5.9.0 Added the `name_field_description`, `slug_field_description`,
 *              `parent_field_description`, and `desc_field_description` labels.
 *
 * @param WP_Taxonomy $tax Taxonomy object.
 * @return object {
 *     Taxonomy labels object. The first default value is for non-hierarchical taxonomies
 *     (like tags) and the second one is for hierarchical taxonomies (like categories).
 *
 *     @type string $name                       General name for the taxonomy, usually plural. The same
 *                                              as and overridden by `$tax->label`. Default 'Tags'/'Categories'.
 *     @type string $singular_name              Name for one object of this taxonomy. Default 'Tag'/'Category'.
 *     @type string $search_items               Default 'Search Tags'/'Search Categories'.
 *     @type string $popular_items              This label is only used for non-hierarchical taxonomies.
 *                                              Default 'Popular Tags'.
 *     @type string $all_items                  Default 'All Tags'/'All Categories'.
 *     @type string $parent_item                This label is only used for hierarchical taxonomies. Default
 *                                              'Parent Category'.
 *     @type string $parent_item_colon          The same as `parent_item`, but with colon `:` in the end.
 *     @type string $name_field_description     Description for the Name field on Edit Tags screen.
 *                                              Default 'The name is how it appears on your site'.
 *     @type string $slug_field_description     Description for the Slug field on Edit Tags screen.
 *                                              Default 'The &#8220;slug&#8221; is the URL-friendly version
 *                                              of the name. It is usually all lowercase and contains
 *                                              only letters, numbers, and hyphens'.
 *     @type string $parent_field_description   Description for the Parent field on Edit Tags screen.
 *                                              Default 'Assign a parent term to create a hierarchy.
 *                                              The term Jazz, for example, would be the parent
 *                                              of Bebop and Big Band'.
 *     @type string $desc_field_description     Description for the Description field on Edit Tags screen.
 *                                              Default 'The description is not prominent by default;
 *                                              however, some themes may show it'.
 *     @type string $edit_item                  Default 'Edit Tag'/'Edit Category'.
 *     @type string $view_item                  Default 'View Tag'/'View Category'.
 *     @type string $update_item                Default 'Update Tag'/'Update Category'.
 *     @type string $add_new_item               Default 'Add New Tag'/'Add New Category'.
 *     @type string $new_item_name              Default 'New Tag Name'/'New Category Name'.
 *     @type string $separate_items_with_commas This label is only used for non-hierarchical taxonomies. Default
 *                                              'Separate tags with commas', used in the meta box.
 *     @type string $add_or_remove_items        This label is only used for non-hierarchical taxonomies. Default
 *                                              'Add or remove tags', used in the meta box when JavaScript
 *                                              is disabled.
 *     @type string $choose_from_most_used      This label is only used on non-hierarchical taxonomies. Default
 *                                              'Choose from the most used tags', used in the meta box.
 *     @type string $not_found                  Default 'No tags found'/'No categories found', used in
 *                                              the meta box and taxonomy list table.
 *     @type string $no_terms                   Default 'No tags'/'No categories', used in the posts and media
 *                                              list tables.
 *     @type string $filter_by_item             This label is only used for hierarchical taxonomies. Default
 *                                              'Filter by category', used in the posts list table.
 *     @type string $items_list_navigation      Label for the table pagination hidden heading.
 *     @type string $items_list                 Label for the table hidden heading.
 *     @type string $most_used                  Title for the Most Used tab. Default 'Most Used'.
 *     @type string $back_to_items              Label displayed after a term has been updated.
 *     @type string $item_link                  Used in the block editor. Title for a navigation link block variation.
 *                                              Default 'Tag Link'/'Category Link'.
 *     @type string $item_link_description      Used in the block editor. Description for a navigation link block
 *                                              variation. Default 'A link to a tag'/'A link to a category'.
 * }
 */
function get_taxonomy_labels( $tax ) {
	$tax->labels = (array) $tax->labels;

	if ( isset( $tax->helps ) && empty( $tax->labels['separate_items_with_commas'] ) ) {
		$tax->labels['separate_items_with_commas'] = $tax->helps;
	}

	if ( isset( $tax->no_tagcloud ) && empty( $tax->labels['not_found'] ) ) {
		$tax->labels['not_found'] = $tax->no_tagcloud;
	}

	$nohier_vs_hier_defaults = WP_Taxonomy::get_default_labels();

	$nohier_vs_hier_defaults['menu_name'] = $nohier_vs_hier_defaults['name'];

	$labels = _get_custom_object_labels( $tax, $nohier_vs_hier_defaults );

	$taxonomy = $tax->name;

	$default_labels = clone $labels;

	/**
	 * Filters the labels of a specific taxonomy.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers to the taxonomy slug.
	 *
	 * Possible hook names include:
	 *
	 *  - `taxonomy_labels_category`
	 *  - `taxonomy_labels_post_tag`
	 *
	 * @since 4.4.0
	 *
	 * @see get_taxonomy_labels() for the full list of taxonomy labels.
	 *
	 * @param object $labels Object with labels for the taxonomy as member variables.
	 */
	$labels = apply_filters( "taxonomy_labels_{$taxonomy}", $labels );

	// Ensure that the filtered labels contain all required default values.
	$labels = (object) array_merge( (array) $default_labels, (array) $labels );

	return $labels;
}

/**
 * Adds an already registered taxonomy to an object type.
 *
 * @since 3.0.0
 *
 * @global WP_Taxonomy[] $wp_taxonomies The registered taxonomies.
 *
 * @param string $taxonomy    Name of taxonomy object.
 * @param string $object_type Name of the object type.
 * @return bool True if successful, false if not.
 */
function register_taxonomy_for_object_type( $taxonomy, $object_type ) {
	global $wp_taxonomies;

	if ( ! isset( $wp_taxonomies[ $taxonomy ] ) ) {
		return false;
	}

	if ( ! get_post_type_object( $object_type ) ) {
		return false;
	}

	if ( ! in_array( $object_type, $wp_taxonomies[ $taxonomy ]->object_type, true ) ) {
		$wp_taxonomies[ $taxonomy ]->object_type[] = $object_type;
	}

	// Filter out empties.
	$wp_taxonomies[ $taxonomy ]->object_type = array_filter( $wp_taxonomies[ $taxonomy ]->object_type );

	/**
	 * Fires after a taxonomy is registered for an object type.
	 *
	 * @since 5.1.0
	 *
	 * @param string $taxonomy    Taxonomy name.
	 * @param string $object_type Name of the object type.
	 */
	do_action( 'registered_taxonomy_for_object_type', $taxonomy, $object_type );

	return true;
}

/**
 * Removes an already registered taxonomy from an object type.
 *
 * @since 3.7.0
 *
 * @global WP_Taxonomy[] $wp_taxonomies The registered taxonomies.
 *
 * @param string $taxonomy    Name of taxonomy object.
 * @param string $object_type Name of the object type.
 * @return bool True if successful, false if not.
 */
function unregister_taxonomy_for_object_type( $taxonomy, $object_type ) {
	global $wp_taxonomies;

	if ( ! isset( $wp_taxonomies[ $taxonomy ] ) ) {
		return false;
	}

	if ( ! get_post_type_object( $object_type ) ) {
		return false;
	}

	$key = array_search( $object_type, $wp_taxonomies[ $taxonomy ]->object_type, true );
	if ( false === $key ) {
		return false;
	}

	unset( $wp_taxonomies[ $taxonomy ]->object_type[ $key ] );

	/**
	 * Fires after a taxonomy is unregistered for an object type.
	 *
	 * @since 5.1.0
	 *
	 * @param string $taxonomy    Taxonomy name.
	 * @param string $object_type Name of the object type.
	 */
	do_action( 'unregistered_taxonomy_for_object_type', $taxonomy, $object_type );

	return true;
}

//
// Term API.
//

/**
 * Retrieves object IDs of valid taxonomy and term.
 *
 * The strings of `$taxonomies` must exist before this function will continue.
 * On failure of finding a valid taxonomy, it will return a WP_Error.
 *
 * The `$terms` aren't checked the same as `$taxonomies`, but still need to exist
 * for object IDs to be returned.
 *
 * It is possible to change the order that object IDs are returned by using `$args`
 * with either ASC or DESC array. The value should be in the key named 'order'.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int|int[]       $term_ids   Term ID or array of term IDs of terms that will be used.
 * @param string|string[] $taxonomies String of taxonomy name or Array of string values of taxonomy names.
 * @param array|string    $args       {
 *     Change the order of the object IDs.
 *
 *     @type string $order Order to retrieve terms. Accepts 'ASC' or 'DESC'. Default 'ASC'.
 * }
 * @return string[]|WP_Error An array of object IDs as numeric strings on success,
 *                           WP_Error if the taxonomy does not exist.
 */
function get_objects_in_term( $term_ids, $taxonomies, $args = array() ) {
	global $wpdb;

	if ( ! is_array( $term_ids ) ) {
		$term_ids = array( $term_ids );
	}
	if ( ! is_array( $taxonomies ) ) {
		$taxonomies = array( $taxonomies );
	}
	foreach ( (array) $taxonomies as $taxonomy ) {
		if ( ! taxonomy_exists( $taxonomy ) ) {
			return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
		}
	}

	$defaults = array( 'order' => 'ASC' );
	$args     = wp_parse_args( $args, $defaults );

	$order = ( 'desc' === strtolower( $args['order'] ) ) ? 'DESC' : 'ASC';

	$term_ids = array_map( 'intval', $term_ids );

	$taxonomies = "'" . implode( "', '", array_map( 'esc_sql', $taxonomies ) ) . "'";
	$term_ids   = "'" . implode( "', '", $term_ids ) . "'";

	$sql = "SELECT tr.object_id FROM $wpdb->term_relationships AS tr INNER JOIN $wpdb->term_taxonomy AS tt ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tt.taxonomy IN ($taxonomies) AND tt.term_id IN ($term_ids) ORDER BY tr.object_id $order";

	$last_changed = wp_cache_get_last_changed( 'terms' );
	$cache_key    = 'get_objects_in_term:' . md5( $sql ) . ":$last_changed";
	$cache        = wp_cache_get( $cache_key, 'term-queries' );
	if ( false === $cache ) {
		$object_ids = $wpdb->get_col( $sql );
		wp_cache_set( $cache_key, $object_ids, 'term-queries' );
	} else {
		$object_ids = (array) $cache;
	}

	if ( ! $object_ids ) {
		return array();
	}
	return $object_ids;
}

/**
 * Given a taxonomy query, generates SQL to be appended to a main query.
 *
 * @since 3.1.0
 *
 * @see WP_Tax_Query
 *
 * @param array  $tax_query         A compact tax query
 * @param string $primary_table
 * @param string $primary_id_column
 * @return string[]
 */
function get_tax_sql( $tax_query, $primary_table, $primary_id_column ) {
	$tax_query_obj = new WP_Tax_Query( $tax_query );
	return $tax_query_obj->get_sql( $primary_table, $primary_id_column );
}

/**
 * Gets all term data from database by term ID.
 *
 * The usage of the get_term function is to apply filters to a term object. It
 * is possible to get a term object from the database before applying the
 * filters.
 *
 * $term ID must be part of $taxonomy, to get from the database. Failure, might
 * be able to be captured by the hooks. Failure would be the same value as $wpdb
 * returns for the get_row method.
 *
 * There are two hooks, one is specifically for each term, named 'get_term', and
 * the second is for the taxonomy name, 'term_$taxonomy'. Both hooks gets the
 * term object, and the taxonomy name as parameters. Both hooks are expected to
 * return a term object.
 *
 * {@see 'get_term'} hook - Takes two parameters the term Object and the taxonomy name.
 * Must return term object. Used in get_term() as a catch-all filter for every
 * $term.
 *
 * {@see 'get_$taxonomy'} hook - Takes two parameters the term Object and the taxonomy
 * name. Must return term object. $taxonomy will be the taxonomy name, so for
 * example, if 'category', it would be 'get_category' as the filter name. Useful
 * for custom taxonomies or plugging into default taxonomies.
 *
 * @todo Better formatting for DocBlock
 *
 * @since 2.3.0
 * @since 4.4.0 Converted to return a WP_Term object if `$output` is `OBJECT`.
 *              The `$taxonomy` parameter was made optional.
 *
 * @see sanitize_term_field() The $context param lists the available values for get_term_by() $filter param.
 *
 * @param int|WP_Term|object $term     If integer, term data will be fetched from the database,
 *                                     or from the cache if available.
 *                                     If stdClass object (as in the results of a database query),
 *                                     will apply filters and return a `WP_Term` object with the `$term` data.
 *                                     If `WP_Term`, will return `$term`.
 * @param string             $taxonomy Optional. Taxonomy name that `$term` is part of.
 * @param string             $output   Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
 *                                     correspond to a WP_Term object, an associative array, or a numeric array,
 *                                     respectively. Default OBJECT.
 * @param string             $filter   Optional. How to sanitize term fields. Default 'raw'.
 * @return WP_Term|array|WP_Error|null WP_Term instance (or array) on success, depending on the `$output` value.
 *                                     WP_Error if `$taxonomy` does not exist. Null for miscellaneous failure.
 */
function get_term( $term, $taxonomy = '', $output = OBJECT, $filter = 'raw' ) {
	if ( empty( $term ) ) {
		return new WP_Error( 'invalid_term', __( 'Empty Term.' ) );
	}

	if ( $taxonomy && ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	if ( $term instanceof WP_Term ) {
		$_term = $term;
	} elseif ( is_object( $term ) ) {
		if ( empty( $term->filter ) || 'raw' === $term->filter ) {
			$_term = sanitize_term( $term, $taxonomy, 'raw' );
			$_term = new WP_Term( $_term );
		} else {
			$_term = WP_Term::get_instance( $term->term_id );
		}
	} else {
		$_term = WP_Term::get_instance( $term, $taxonomy );
	}

	if ( is_wp_error( $_term ) ) {
		return $_term;
	} elseif ( ! $_term ) {
		return null;
	}

	// Ensure for filters that this is not empty.
	$taxonomy = $_term->taxonomy;

	$old_term = $_term;
	/**
	 * Filters a taxonomy term object.
	 *
	 * The {@see 'get_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 2.3.0
	 * @since 4.4.0 `$_term` is now a `WP_Term` object.
	 *
	 * @param WP_Term $_term    Term object.
	 * @param string  $taxonomy The taxonomy slug.
	 */
	$_term = apply_filters( 'get_term', $_term, $taxonomy );

	/**
	 * Filters a taxonomy term object.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers
	 * to the slug of the term's taxonomy.
	 *
	 * Possible hook names include:
	 *
	 *  - `get_category`
	 *  - `get_post_tag`
	 *
	 * @since 2.3.0
	 * @since 4.4.0 `$_term` is now a `WP_Term` object.
	 *
	 * @param WP_Term $_term    Term object.
	 * @param string  $taxonomy The taxonomy slug.
	 */
	$_term = apply_filters( "get_{$taxonomy}", $_term, $taxonomy );

	// Bail if a filter callback has changed the type of the `$_term` object.
	if ( ! ( $_term instanceof WP_Term ) ) {
		return $_term;
	}

	// Sanitize term, according to the specified filter.
	if ( $_term !== $old_term || $_term->filter !== $filter ) {
		$_term->filter( $filter );
	}

	if ( ARRAY_A === $output ) {
		return $_term->to_array();
	} elseif ( ARRAY_N === $output ) {
		return array_values( $_term->to_array() );
	}

	return $_term;
}

/**
 * Gets all term data from database by term field and data.
 *
 * Warning: $value is not escaped for 'name' $field. You must do it yourself, if
 * required.
 *
 * The default $field is 'id', therefore it is possible to also use null for
 * field, but not recommended that you do so.
 *
 * If $value does not exist, the return value will be false. If $taxonomy exists
 * and $field and $value combinations exist, the term will be returned.
 *
 * This function will always return the first term that matches the `$field`-
 * `$value`-`$taxonomy` combination specified in the parameters. If your query
 * is likely to match more than one term (as is likely to be the case when
 * `$field` is 'name', for example), consider using get_terms() instead; that
 * way, you will get all matching terms, and can provide your own logic for
 * deciding which one was intended.
 *
 * @todo Better formatting for DocBlock.
 *
 * @since 2.3.0
 * @since 4.4.0 `$taxonomy` is optional if `$field` is 'term_taxonomy_id'. Converted to return
 *              a WP_Term object if `$output` is `OBJECT`.
 * @since 5.5.0 Added 'ID' as an alias of 'id' for the `$field` parameter.
 *
 * @see sanitize_term_field() The $context param lists the available values for get_term_by() $filter param.
 *
 * @param string     $field    Either 'slug', 'name', 'term_id' (or 'id', 'ID'), or 'term_taxonomy_id'.
 * @param string|int $value    Search for this term value.
 * @param string     $taxonomy Taxonomy name. Optional, if `$field` is 'term_taxonomy_id'.
 * @param string     $output   Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
 *                             correspond to a WP_Term object, an associative array, or a numeric array,
 *                             respectively. Default OBJECT.
 * @param string     $filter   Optional. How to sanitize term fields. Default 'raw'.
 * @return WP_Term|array|false WP_Term instance (or array) on success, depending on the `$output` value.
 *                             False if `$taxonomy` does not exist or `$term` was not found.
 */
function get_term_by( $field, $value, $taxonomy = '', $output = OBJECT, $filter = 'raw' ) {

	// 'term_taxonomy_id' lookups don't require taxonomy checks.
	if ( 'term_taxonomy_id' !== $field && ! taxonomy_exists( $taxonomy ) ) {
		return false;
	}

	// No need to perform a query for empty 'slug' or 'name'.
	if ( 'slug' === $field || 'name' === $field ) {
		$value = (string) $value;

		if ( 0 === strlen( $value ) ) {
			return false;
		}
	}

	if ( 'id' === $field || 'ID' === $field || 'term_id' === $field ) {
		$term = get_term( (int) $value, $taxonomy, $output, $filter );
		if ( is_wp_error( $term ) || null === $term ) {
			$term = false;
		}
		return $term;
	}

	$args = array(
		'get'                    => 'all',
		'number'                 => 1,
		'taxonomy'               => $taxonomy,
		'update_term_meta_cache' => false,
		'orderby'                => 'none',
		'suppress_filter'        => true,
	);

	switch ( $field ) {
		case 'slug':
			$args['slug'] = $value;
			break;
		case 'name':
			$args['name'] = $value;
			break;
		case 'term_taxonomy_id':
			$args['term_taxonomy_id'] = $value;
			unset( $args['taxonomy'] );
			break;
		default:
			return false;
	}

	$terms = get_terms( $args );
	if ( is_wp_error( $terms ) || empty( $terms ) ) {
		return false;
	}

	$term = array_shift( $terms );

	// In the case of 'term_taxonomy_id', override the provided `$taxonomy` with whatever we find in the DB.
	if ( 'term_taxonomy_id' === $field ) {
		$taxonomy = $term->taxonomy;
	}

	return get_term( $term, $taxonomy, $output, $filter );
}

/**
 * Merges all term children into a single array of their IDs.
 *
 * This recursive function will merge all of the children of $term into the same
 * array of term IDs. Only useful for taxonomies which are hierarchical.
 *
 * Will return an empty array if $term does not exist in $taxonomy.
 *
 * @since 2.3.0
 *
 * @param int    $term_id  ID of term to get children.
 * @param string $taxonomy Taxonomy name.
 * @return array|WP_Error List of term IDs. WP_Error returned if `$taxonomy` does not exist.
 */
function get_term_children( $term_id, $taxonomy ) {
	if ( ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	$term_id = (int) $term_id;

	$terms = _get_term_hierarchy( $taxonomy );

	if ( ! isset( $terms[ $term_id ] ) ) {
		return array();
	}

	$children = $terms[ $term_id ];

	foreach ( (array) $terms[ $term_id ] as $child ) {
		if ( $term_id === $child ) {
			continue;
		}

		if ( isset( $terms[ $child ] ) ) {
			$children = array_merge( $children, get_term_children( $child, $taxonomy ) );
		}
	}

	return $children;
}

/**
 * Gets sanitized term field.
 *
 * The function is for contextual reasons and for simplicity of usage.
 *
 * @since 2.3.0
 * @since 4.4.0 The `$taxonomy` parameter was made optional. `$term` can also now accept a WP_Term object.
 *
 * @see sanitize_term_field()
 *
 * @param string      $field    Term field to fetch.
 * @param int|WP_Term $term     Term ID or object.
 * @param string      $taxonomy Optional. Taxonomy name. Default empty.
 * @param string      $context  Optional. How to sanitize term fields. Look at sanitize_term_field() for available options.
 *                              Default 'display'.
 * @return string|int|null|WP_Error Will return an empty string if $term is not an object or if $field is not set in $term.
 */
function get_term_field( $field, $term, $taxonomy = '', $context = 'display' ) {
	$term = get_term( $term, $taxonomy );
	if ( is_wp_error( $term ) ) {
		return $term;
	}

	if ( ! is_object( $term ) ) {
		return '';
	}

	if ( ! isset( $term->$field ) ) {
		return '';
	}

	return sanitize_term_field( $field, $term->$field, $term->term_id, $term->taxonomy, $context );
}

/**
 * Sanitizes term for editing.
 *
 * Return value is sanitize_term() and usage is for sanitizing the term for
 * editing. Function is for contextual and simplicity.
 *
 * @since 2.3.0
 *
 * @param int|object $id       Term ID or object.
 * @param string     $taxonomy Taxonomy name.
 * @return string|int|null|WP_Error Will return empty string if $term is not an object.
 */
function get_term_to_edit( $id, $taxonomy ) {
	$term = get_term( $id, $taxonomy );

	if ( is_wp_error( $term ) ) {
		return $term;
	}

	if ( ! is_object( $term ) ) {
		return '';
	}

	return sanitize_term( $term, $taxonomy, 'edit' );
}

/**
 * Retrieves the terms in a given taxonomy or list of taxonomies.
 *
 * You can fully inject any customizations to the query before it is sent, as
 * well as control the output with a filter.
 *
 * The return type varies depending on the value passed to `$args['fields']`. See
 * WP_Term_Query::get_terms() for details. In all cases, a `WP_Error` object will
 * be returned if an invalid taxonomy is requested.
 *
 * The {@see 'get_terms'} filter will be called when the cache has the term and will
 * pass the found term along with the array of $taxonomies and array of $args.
 * This filter is also called before the array of terms is passed and will pass
 * the array of terms, along with the $taxonomies and $args.
 *
 * The {@see 'list_terms_exclusions'} filter passes the compiled exclusions along with
 * the $args.
 *
 * The {@see 'get_terms_orderby'} filter passes the `ORDER BY` clause for the query
 * along with the $args array.
 *
 * Taxonomy or an array of taxonomies should be passed via the 'taxonomy' argument
 * in the `$args` array:
 *
 *     $terms = get_terms( array(
 *         'taxonomy'   => 'post_tag',
 *         'hide_empty' => false,
 *     ) );
 *
 * Prior to 4.5.0, taxonomy was passed as the first parameter of `get_terms()`.
 *
 * @since 2.3.0
 * @since 4.2.0 Introduced 'name' and 'childless' parameters.
 * @since 4.4.0 Introduced the ability to pass 'term_id' as an alias of 'id' for the `orderby` parameter.
 *              Introduced the 'meta_query' and 'update_term_meta_cache' parameters. Converted to return
 *              a list of WP_Term objects.
 * @since 4.5.0 Changed the function signature so that the `$args` array can be provided as the first parameter.
 *              Introduced 'meta_key' and 'meta_value' parameters. Introduced the ability to order results by metadata.
 * @since 4.8.0 Introduced 'suppress_filter' parameter.
 *
 * @internal The `$deprecated` parameter is parsed for backward compatibility only.
 *
 * @param array|string $args       Optional. Array or string of arguments. See WP_Term_Query::__construct()
 *                                 for information on accepted arguments. Default empty array.
 * @param array|string $deprecated Optional. Argument array, when using the legacy function parameter format.
 *                                 If present, this parameter will be interpreted as `$args`, and the first
 *                                 function parameter will be parsed as a taxonomy or array of taxonomies.
 *                                 Default empty.
 * @return WP_Term[]|int[]|string[]|string|WP_Error Array of terms, a count thereof as a numeric string,
 *                                                  or WP_Error if any of the taxonomies do not exist.
 *                                                  See the function description for more information.
 */
function get_terms( $args = array(), $deprecated = '' ) {
	$term_query = new WP_Term_Query();

	$defaults = array(
		'suppress_filter' => false,
	);

	/*
	 * Legacy argument format ($taxonomy, $args) takes precedence.
	 *
	 * We detect legacy argument format by checking if
	 * (a) a second non-empty parameter is passed, or
	 * (b) the first parameter shares no keys with the default array (ie, it's a list of taxonomies)
	 */
	$_args          = wp_parse_args( $args );
	$key_intersect  = array_intersect_key( $term_query->query_var_defaults, (array) $_args );
	$do_legacy_args = $deprecated || empty( $key_intersect );

	if ( $do_legacy_args ) {
		$taxonomies       = (array) $args;
		$args             = wp_parse_args( $deprecated, $defaults );
		$args['taxonomy'] = $taxonomies;
	} else {
		$args = wp_parse_args( $args, $defaults );
		if ( isset( $args['taxonomy'] ) && null !== $args['taxonomy'] ) {
			$args['taxonomy'] = (array) $args['taxonomy'];
		}
	}

	if ( ! empty( $args['taxonomy'] ) ) {
		foreach ( $args['taxonomy'] as $taxonomy ) {
			if ( ! taxonomy_exists( $taxonomy ) ) {
				return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
			}
		}
	}

	// Don't pass suppress_filter to WP_Term_Query.
	$suppress_filter = $args['suppress_filter'];
	unset( $args['suppress_filter'] );

	$terms = $term_query->query( $args );

	// Count queries are not filtered, for legacy reasons.
	if ( ! is_array( $terms ) ) {
		return $terms;
	}

	if ( $suppress_filter ) {
		return $terms;
	}

	/**
	 * Filters the found terms.
	 *
	 * @since 2.3.0
	 * @since 4.6.0 Added the `$term_query` parameter.
	 *
	 * @param array         $terms      Array of found terms.
	 * @param array|null    $taxonomies An array of taxonomies if known.
	 * @param array         $args       An array of get_terms() arguments.
	 * @param WP_Term_Query $term_query The WP_Term_Query object.
	 */
	return apply_filters( 'get_terms', $terms, $term_query->query_vars['taxonomy'], $term_query->query_vars, $term_query );
}

/**
 * Adds metadata to a term.
 *
 * @since 4.4.0
 *
 * @param int    $term_id    Term ID.
 * @param string $meta_key   Metadata name.
 * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
 * @param bool   $unique     Optional. Whether the same key should not be added.
 *                           Default false.
 * @return int|false|WP_Error Meta ID on success, false on failure.
 *                            WP_Error when term_id is ambiguous between taxonomies.
 */
function add_term_meta( $term_id, $meta_key, $meta_value, $unique = false ) {
	if ( wp_term_is_shared( $term_id ) ) {
		return new WP_Error( 'ambiguous_term_id', __( 'Term meta cannot be added to terms that are shared between taxonomies.' ), $term_id );
	}

	return add_metadata( 'term', $term_id, $meta_key, $meta_value, $unique );
}

/**
 * Removes metadata matching criteria from a term.
 *
 * @since 4.4.0
 *
 * @param int    $term_id    Term ID.
 * @param string $meta_key   Metadata name.
 * @param mixed  $meta_value Optional. Metadata value. If provided,
 *                           rows will only be removed that match the value.
 *                           Must be serializable if non-scalar. Default empty.
 * @return bool True on success, false on failure.
 */
function delete_term_meta( $term_id, $meta_key, $meta_value = '' ) {
	return delete_metadata( 'term', $term_id, $meta_key, $meta_value );
}

/**
 * Retrieves metadata for a term.
 *
 * @since 4.4.0
 *
 * @param int    $term_id Term ID.
 * @param string $key     Optional. The meta key to retrieve. By default,
 *                        returns data for all keys. Default empty.
 * @param bool   $single  Optional. Whether to return a single value.
 *                        This parameter has no effect if `$key` is not specified.
 *                        Default false.
 * @return mixed An array of values if `$single` is false.
 *               The value of the meta field if `$single` is true.
 *               False for an invalid `$term_id` (non-numeric, zero, or negative value).
 *               An empty string if a valid but non-existing term ID is passed.
 */
function get_term_meta( $term_id, $key = '', $single = false ) {
	return get_metadata( 'term', $term_id, $key, $single );
}

/**
 * Updates term metadata.
 *
 * Use the `$prev_value` parameter to differentiate between meta fields with the same key and term ID.
 *
 * If the meta field for the term does not exist, it will be added.
 *
 * @since 4.4.0
 *
 * @param int    $term_id    Term ID.
 * @param string $meta_key   Metadata key.
 * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
 * @param mixed  $prev_value Optional. Previous value to check before updating.
 *                           If specified, only update existing metadata entries with
 *                           this value. Otherwise, update all entries. Default empty.
 * @return int|bool|WP_Error Meta ID if the key didn't exist. true on successful update,
 *                           false on failure or if the value passed to the function
 *                           is the same as the one that is already in the database.
 *                           WP_Error when term_id is ambiguous between taxonomies.
 */
function update_term_meta( $term_id, $meta_key, $meta_value, $prev_value = '' ) {
	if ( wp_term_is_shared( $term_id ) ) {
		return new WP_Error( 'ambiguous_term_id', __( 'Term meta cannot be added to terms that are shared between taxonomies.' ), $term_id );
	}

	return update_metadata( 'term', $term_id, $meta_key, $meta_value, $prev_value );
}

/**
 * Updates metadata cache for list of term IDs.
 *
 * Performs SQL query to retrieve all metadata for the terms matching `$term_ids` and stores them in the cache.
 * Subsequent calls to `get_term_meta()` will not need to query the database.
 *
 * @since 4.4.0
 *
 * @param array $term_ids List of term IDs.
 * @return array|false An array of metadata on success, false if there is nothing to update.
 */
function update_termmeta_cache( $term_ids ) {
	return update_meta_cache( 'term', $term_ids );
}


/**
 * Queue term meta for lazy-loading.
 *
 * @since 6.3.0
 *
 * @param array $term_ids List of term IDs.
 */
function wp_lazyload_term_meta( array $term_ids ) {
	if ( empty( $term_ids ) ) {
		return;
	}
	$lazyloader = wp_metadata_lazyloader();
	$lazyloader->queue_objects( 'term', $term_ids );
}

/**
 * Gets all meta data, including meta IDs, for the given term ID.
 *
 * @since 4.9.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int $term_id Term ID.
 * @return array|false Array with meta data, or false when the meta table is not installed.
 */
function has_term_meta( $term_id ) {
	$check = wp_check_term_meta_support_prefilter( null );
	if ( null !== $check ) {
		return $check;
	}

	global $wpdb;

	return $wpdb->get_results( $wpdb->prepare( "SELECT meta_key, meta_value, meta_id, term_id FROM $wpdb->termmeta WHERE term_id = %d ORDER BY meta_key,meta_id", $term_id ), ARRAY_A );
}

/**
 * Registers a meta key for terms.
 *
 * @since 4.9.8
 *
 * @param string $taxonomy Taxonomy to register a meta key for. Pass an empty string
 *                         to register the meta key across all existing taxonomies.
 * @param string $meta_key The meta key to register.
 * @param array  $args     Data used to describe the meta key when registered. See
 *                         {@see register_meta()} for a list of supported arguments.
 * @return bool True if the meta key was successfully registered, false if not.
 */
function register_term_meta( $taxonomy, $meta_key, array $args ) {
	$args['object_subtype'] = $taxonomy;

	return register_meta( 'term', $meta_key, $args );
}

/**
 * Unregisters a meta key for terms.
 *
 * @since 4.9.8
 *
 * @param string $taxonomy Taxonomy the meta key is currently registered for. Pass
 *                         an empty string if the meta key is registered across all
 *                         existing taxonomies.
 * @param string $meta_key The meta key to unregister.
 * @return bool True on success, false if the meta key was not previously registered.
 */
function unregister_term_meta( $taxonomy, $meta_key ) {
	return unregister_meta_key( 'term', $meta_key, $taxonomy );
}

/**
 * Determines whether a taxonomy term exists.
 *
 * Formerly is_term(), introduced in 2.3.0.
 *
 * For more information on this and similar theme functions, check out
 * the {@link https://developer.wordpress.org/themes/basics/conditional-tags/
 * Conditional Tags} article in the Theme Developer Handbook.
 *
 * @since 3.0.0
 * @since 6.0.0 Converted to use `get_terms()`.
 *
 * @global bool $_wp_suspend_cache_invalidation
 *
 * @param int|string $term        The term to check. Accepts term ID, slug, or name.
 * @param string     $taxonomy    Optional. The taxonomy name to use.
 * @param int        $parent_term Optional. ID of parent term under which to confine the exists search.
 * @return mixed Returns null if the term does not exist.
 *               Returns the term ID if no taxonomy is specified and the term ID exists.
 *               Returns an array of the term ID and the term taxonomy ID if the taxonomy is specified and the pairing exists.
 *               Returns 0 if term ID 0 is passed to the function.
 */
function term_exists( $term, $taxonomy = '', $parent_term = null ) {
	global $_wp_suspend_cache_invalidation;

	if ( null === $term ) {
		return null;
	}

	$defaults = array(
		'get'                    => 'all',
		'fields'                 => 'ids',
		'number'                 => 1,
		'update_term_meta_cache' => false,
		'order'                  => 'ASC',
		'orderby'                => 'term_id',
		'suppress_filter'        => true,
	);

	// Ensure that while importing, queries are not cached.
	if ( ! empty( $_wp_suspend_cache_invalidation ) ) {
		$defaults['cache_results'] = false;
	}

	if ( ! empty( $taxonomy ) ) {
		$defaults['taxonomy'] = $taxonomy;
		$defaults['fields']   = 'all';
	}

	/**
	 * Filters default query arguments for checking if a term exists.
	 *
	 * @since 6.0.0
	 *
	 * @param array      $defaults    An array of arguments passed to get_terms().
	 * @param int|string $term        The term to check. Accepts term ID, slug, or name.
	 * @param string     $taxonomy    The taxonomy name to use. An empty string indicates
	 *                                the search is against all taxonomies.
	 * @param int|null   $parent_term ID of parent term under which to confine the exists search.
	 *                                Null indicates the search is unconfined.
	 */
	$defaults = apply_filters( 'term_exists_default_query_args', $defaults, $term, $taxonomy, $parent_term );

	if ( is_int( $term ) ) {
		if ( 0 === $term ) {
			return 0;
		}
		$args  = wp_parse_args( array( 'include' => array( $term ) ), $defaults );
		$terms = get_terms( $args );
	} else {
		$term = trim( wp_unslash( $term ) );
		if ( '' === $term ) {
			return null;
		}

		if ( ! empty( $taxonomy ) && is_numeric( $parent_term ) ) {
			$defaults['parent'] = (int) $parent_term;
		}

		$args  = wp_parse_args( array( 'slug' => sanitize_title( $term ) ), $defaults );
		$terms = get_terms( $args );
		if ( empty( $terms ) || is_wp_error( $terms ) ) {
			$args  = wp_parse_args( array( 'name' => $term ), $defaults );
			$terms = get_terms( $args );
		}
	}

	if ( empty( $terms ) || is_wp_error( $terms ) ) {
		return null;
	}

	$_term = array_shift( $terms );

	if ( ! empty( $taxonomy ) ) {
		return array(
			'term_id'          => (string) $_term->term_id,
			'term_taxonomy_id' => (string) $_term->term_taxonomy_id,
		);
	}

	return (string) $_term;
}

/**
 * Checks if a term is an ancestor of another term.
 *
 * You can use either an ID or the term object for both parameters.
 *
 * @since 3.4.0
 *
 * @param int|object $term1    ID or object to check if this is the parent term.
 * @param int|object $term2    The child term.
 * @param string     $taxonomy Taxonomy name that $term1 and `$term2` belong to.
 * @return bool Whether `$term2` is a child of `$term1`.
 */
function term_is_ancestor_of( $term1, $term2, $taxonomy ) {
	if ( ! isset( $term1->term_id ) ) {
		$term1 = get_term( $term1, $taxonomy );
	}
	if ( ! isset( $term2->parent ) ) {
		$term2 = get_term( $term2, $taxonomy );
	}

	if ( empty( $term1->term_id ) || empty( $term2->parent ) ) {
		return false;
	}
	if ( $term2->parent === $term1->term_id ) {
		return true;
	}

	return term_is_ancestor_of( $term1, get_term( $term2->parent, $taxonomy ), $taxonomy );
}

/**
 * Sanitizes all term fields.
 *
 * Relies on sanitize_term_field() to sanitize the term. The difference is that
 * this function will sanitize **all** fields. The context is based
 * on sanitize_term_field().
 *
 * The `$term` is expected to be either an array or an object.
 *
 * @since 2.3.0
 *
 * @param array|object $term     The term to check.
 * @param string       $taxonomy The taxonomy name to use.
 * @param string       $context  Optional. Context in which to sanitize the term.
 *                               Accepts 'raw', 'edit', 'db', 'display', 'rss',
 *                               'attribute', or 'js'. Default 'display'.
 * @return array|object Term with all fields sanitized.
 */
function sanitize_term( $term, $taxonomy, $context = 'display' ) {
	$fields = array( 'term_id', 'name', 'description', 'slug', 'count', 'parent', 'term_group', 'term_taxonomy_id', 'object_id' );

	$do_object = is_object( $term );

	$term_id = $do_object ? $term->term_id : ( isset( $term['term_id'] ) ? $term['term_id'] : 0 );

	foreach ( (array) $fields as $field ) {
		if ( $do_object ) {
			if ( isset( $term->$field ) ) {
				$term->$field = sanitize_term_field( $field, $term->$field, $term_id, $taxonomy, $context );
			}
		} else {
			if ( isset( $term[ $field ] ) ) {
				$term[ $field ] = sanitize_term_field( $field, $term[ $field ], $term_id, $taxonomy, $context );
			}
		}
	}

	if ( $do_object ) {
		$term->filter = $context;
	} else {
		$term['filter'] = $context;
	}

	return $term;
}

/**
 * Sanitizes the field value in the term based on the context.
 *
 * Passing a term field value through the function should be assumed to have
 * cleansed the value for whatever context the term field is going to be used.
 *
 * If no context or an unsupported context is given, then default filters will
 * be applied.
 *
 * There are enough filters for each context to support a custom filtering
 * without creating your own filter function. Simply create a function that
 * hooks into the filter you need.
 *
 * @since 2.3.0
 *
 * @param string $field    Term field to sanitize.
 * @param string $value    Search for this term value.
 * @param int    $term_id  Term ID.
 * @param string $taxonomy Taxonomy name.
 * @param string $context  Context in which to sanitize the term field.
 *                         Accepts 'raw', 'edit', 'db', 'display', 'rss',
 *                         'attribute', or 'js'. Default 'display'.
 * @return mixed Sanitized field.
 */
function sanitize_term_field( $field, $value, $term_id, $taxonomy, $context ) {
	$int_fields = array( 'parent', 'term_id', 'count', 'term_group', 'term_taxonomy_id', 'object_id' );
	if ( in_array( $field, $int_fields, true ) ) {
		$value = (int) $value;
		if ( $value < 0 ) {
			$value = 0;
		}
	}

	$context = strtolower( $context );

	if ( 'raw' === $context ) {
		return $value;
	}

	if ( 'edit' === $context ) {

		/**
		 * Filters a term field to edit before it is sanitized.
		 *
		 * The dynamic portion of the hook name, `$field`, refers to the term field.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed $value     Value of the term field.
		 * @param int   $term_id   Term ID.
		 * @param string $taxonomy Taxonomy slug.
		 */
		$value = apply_filters( "edit_term_{$field}", $value, $term_id, $taxonomy );

		/**
		 * Filters the taxonomy field to edit before it is sanitized.
		 *
		 * The dynamic portions of the filter name, `$taxonomy` and `$field`, refer
		 * to the taxonomy slug and taxonomy field, respectively.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed $value   Value of the taxonomy field to edit.
		 * @param int   $term_id Term ID.
		 */
		$value = apply_filters( "edit_{$taxonomy}_{$field}", $value, $term_id );

		if ( 'description' === $field ) {
			$value = esc_html( $value ); // textarea_escaped
		} else {
			$value = esc_attr( $value );
		}
	} elseif ( 'db' === $context ) {

		/**
		 * Filters a term field value before it is sanitized.
		 *
		 * The dynamic portion of the hook name, `$field`, refers to the term field.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed  $value    Value of the term field.
		 * @param string $taxonomy Taxonomy slug.
		 */
		$value = apply_filters( "pre_term_{$field}", $value, $taxonomy );

		/**
		 * Filters a taxonomy field before it is sanitized.
		 *
		 * The dynamic portions of the filter name, `$taxonomy` and `$field`, refer
		 * to the taxonomy slug and field name, respectively.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed $value Value of the taxonomy field.
		 */
		$value = apply_filters( "pre_{$taxonomy}_{$field}", $value );

		// Back compat filters.
		if ( 'slug' === $field ) {
			/**
			 * Filters the category nicename before it is sanitized.
			 *
			 * Use the {@see 'pre_$taxonomy_$field'} hook instead.
			 *
			 * @since 2.0.3
			 *
			 * @param string $value The category nicename.
			 */
			$value = apply_filters( 'pre_category_nicename', $value );
		}
	} elseif ( 'rss' === $context ) {

		/**
		 * Filters the term field for use in RSS.
		 *
		 * The dynamic portion of the hook name, `$field`, refers to the term field.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed  $value    Value of the term field.
		 * @param string $taxonomy Taxonomy slug.
		 */
		$value = apply_filters( "term_{$field}_rss", $value, $taxonomy );

		/**
		 * Filters the taxonomy field for use in RSS.
		 *
		 * The dynamic portions of the hook name, `$taxonomy`, and `$field`, refer
		 * to the taxonomy slug and field name, respectively.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed $value Value of the taxonomy field.
		 */
		$value = apply_filters( "{$taxonomy}_{$field}_rss", $value );
	} else {
		// Use display filters by default.

		/**
		 * Filters the term field sanitized for display.
		 *
		 * The dynamic portion of the hook name, `$field`, refers to the term field name.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed  $value    Value of the term field.
		 * @param int    $term_id  Term ID.
		 * @param string $taxonomy Taxonomy slug.
		 * @param string $context  Context to retrieve the term field value.
		 */
		$value = apply_filters( "term_{$field}", $value, $term_id, $taxonomy, $context );

		/**
		 * Filters the taxonomy field sanitized for display.
		 *
		 * The dynamic portions of the filter name, `$taxonomy`, and `$field`, refer
		 * to the taxonomy slug and taxonomy field, respectively.
		 *
		 * @since 2.3.0
		 *
		 * @param mixed  $value   Value of the taxonomy field.
		 * @param int    $term_id Term ID.
		 * @param string $context Context to retrieve the taxonomy field value.
		 */
		$value = apply_filters( "{$taxonomy}_{$field}", $value, $term_id, $context );
	}

	if ( 'attribute' === $context ) {
		$value = esc_attr( $value );
	} elseif ( 'js' === $context ) {
		$value = esc_js( $value );
	}

	// Restore the type for integer fields after esc_attr().
	if ( in_array( $field, $int_fields, true ) ) {
		$value = (int) $value;
	}

	return $value;
}

/**
 * Counts how many terms are in taxonomy.
 *
 * Default $args is 'hide_empty' which can be 'hide_empty=true' or array('hide_empty' => true).
 *
 * @since 2.3.0
 * @since 5.6.0 Changed the function signature so that the `$args` array can be provided as the first parameter.
 *
 * @internal The `$deprecated` parameter is parsed for backward compatibility only.
 *
 * @param array|string $args       Optional. Array or string of arguments. See WP_Term_Query::__construct()
 *                                 for information on accepted arguments. Default empty array.
 * @param array|string $deprecated Optional. Argument array, when using the legacy function parameter format.
 *                                 If present, this parameter will be interpreted as `$args`, and the first
 *                                 function parameter will be parsed as a taxonomy or array of taxonomies.
 *                                 Default empty.
 * @return string|WP_Error Numeric string containing the number of terms in that
 *                         taxonomy or WP_Error if the taxonomy does not exist.
 */
function wp_count_terms( $args = array(), $deprecated = '' ) {
	$use_legacy_args = false;

	// Check whether function is used with legacy signature: `$taxonomy` and `$args`.
	if ( $args
		&& ( is_string( $args ) && taxonomy_exists( $args )
			|| is_array( $args ) && wp_is_numeric_array( $args ) )
	) {
		$use_legacy_args = true;
	}

	$defaults = array( 'hide_empty' => false );

	if ( $use_legacy_args ) {
		$defaults['taxonomy'] = $args;
		$args                 = $deprecated;
	}

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

	// Backward compatibility.
	if ( isset( $args['ignore_empty'] ) ) {
		$args['hide_empty'] = $args['ignore_empty'];
		unset( $args['ignore_empty'] );
	}

	$args['fields'] = 'count';

	return get_terms( $args );
}

/**
 * Unlinks the object from the taxonomy or taxonomies.
 *
 * Will remove all relationships between the object and any terms in
 * a particular taxonomy or taxonomies. Does not remove the term or
 * taxonomy itself.
 *
 * @since 2.3.0
 *
 * @param int          $object_id  The term object ID that refers to the term.
 * @param string|array $taxonomies List of taxonomy names or single taxonomy name.
 */
function wp_delete_object_term_relationships( $object_id, $taxonomies ) {
	$object_id = (int) $object_id;

	if ( ! is_array( $taxonomies ) ) {
		$taxonomies = array( $taxonomies );
	}

	foreach ( (array) $taxonomies as $taxonomy ) {
		$term_ids = wp_get_object_terms( $object_id, $taxonomy, array( 'fields' => 'ids' ) );
		$term_ids = array_map( 'intval', $term_ids );
		wp_remove_object_terms( $object_id, $term_ids, $taxonomy );
	}
}

/**
 * Removes a term from the database.
 *
 * If the term is a parent of other terms, then the children will be updated to
 * that term's parent.
 *
 * Metadata associated with the term will be deleted.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int          $term     Term ID.
 * @param string       $taxonomy Taxonomy name.
 * @param array|string $args {
 *     Optional. Array of arguments to override the default term ID. Default empty array.
 *
 *     @type int  $default       The term ID to make the default term. This will only override
 *                               the terms found if there is only one term found. Any other and
 *                               the found terms are used.
 *     @type bool $force_default Optional. Whether to force the supplied term as default to be
 *                               assigned even if the object was not going to be term-less.
 *                               Default false.
 * }
 * @return bool|int|WP_Error True on success, false if term does not exist. Zero on attempted
 *                           deletion of default Category. WP_Error if the taxonomy does not exist.
 */
function wp_delete_term( $term, $taxonomy, $args = array() ) {
	global $wpdb;

	$term = (int) $term;

	$ids = term_exists( $term, $taxonomy );
	if ( ! $ids ) {
		return false;
	}
	if ( is_wp_error( $ids ) ) {
		return $ids;
	}

	$tt_id = $ids['term_taxonomy_id'];

	$defaults = array();

	if ( 'category' === $taxonomy ) {
		$defaults['default'] = (int) get_option( 'default_category' );
		if ( $defaults['default'] === $term ) {
			return 0; // Don't delete the default category.
		}
	}

	// Don't delete the default custom taxonomy term.
	$taxonomy_object = get_taxonomy( $taxonomy );
	if ( ! empty( $taxonomy_object->default_term ) ) {
		$defaults['default'] = (int) get_option( 'default_term_' . $taxonomy );
		if ( $defaults['default'] === $term ) {
			return 0;
		}
	}

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

	if ( isset( $args['default'] ) ) {
		$default = (int) $args['default'];
		if ( ! term_exists( $default, $taxonomy ) ) {
			unset( $default );
		}
	}

	if ( isset( $args['force_default'] ) ) {
		$force_default = $args['force_default'];
	}

	/**
	 * Fires when deleting a term, before any modifications are made to posts or terms.
	 *
	 * @since 4.1.0
	 *
	 * @param int    $term     Term ID.
	 * @param string $taxonomy Taxonomy name.
	 */
	do_action( 'pre_delete_term', $term, $taxonomy );

	// Update children to point to new parent.
	if ( is_taxonomy_hierarchical( $taxonomy ) ) {
		$term_obj = get_term( $term, $taxonomy );
		if ( is_wp_error( $term_obj ) ) {
			return $term_obj;
		}
		$parent = $term_obj->parent;

		$edit_ids    = $wpdb->get_results( "SELECT term_id, term_taxonomy_id FROM $wpdb->term_taxonomy WHERE `parent` = " . (int) $term_obj->term_id );
		$edit_tt_ids = wp_list_pluck( $edit_ids, 'term_taxonomy_id' );

		/**
		 * Fires immediately before a term to delete's children are reassigned a parent.
		 *
		 * @since 2.9.0
		 *
		 * @param array $edit_tt_ids An array of term taxonomy IDs for the given term.
		 */
		do_action( 'edit_term_taxonomies', $edit_tt_ids );

		$wpdb->update( $wpdb->term_taxonomy, compact( 'parent' ), array( 'parent' => $term_obj->term_id ) + compact( 'taxonomy' ) );

		// Clean the cache for all child terms.
		$edit_term_ids = wp_list_pluck( $edit_ids, 'term_id' );
		clean_term_cache( $edit_term_ids, $taxonomy );

		/**
		 * Fires immediately after a term to delete's children are reassigned a parent.
		 *
		 * @since 2.9.0
		 *
		 * @param array $edit_tt_ids An array of term taxonomy IDs for the given term.
		 */
		do_action( 'edited_term_taxonomies', $edit_tt_ids );
	}

	// Get the term before deleting it or its term relationships so we can pass to actions below.
	$deleted_term = get_term( $term, $taxonomy );

	$object_ids = (array) $wpdb->get_col( $wpdb->prepare( "SELECT object_id FROM $wpdb->term_relationships WHERE term_taxonomy_id = %d", $tt_id ) );

	foreach ( $object_ids as $object_id ) {
		if ( ! isset( $default ) ) {
			wp_remove_object_terms( $object_id, $term, $taxonomy );
			continue;
		}

		$terms = wp_get_object_terms(
			$object_id,
			$taxonomy,
			array(
				'fields'  => 'ids',
				'orderby' => 'none',
			)
		);

		if ( 1 === count( $terms ) && isset( $default ) ) {
			$terms = array( $default );
		} else {
			$terms = array_diff( $terms, array( $term ) );
			if ( isset( $default ) && isset( $force_default ) && $force_default ) {
				$terms = array_merge( $terms, array( $default ) );
			}
		}

		$terms = array_map( 'intval', $terms );
		wp_set_object_terms( $object_id, $terms, $taxonomy );
	}

	// Clean the relationship caches for all object types using this term.
	$tax_object = get_taxonomy( $taxonomy );
	foreach ( $tax_object->object_type as $object_type ) {
		clean_object_term_cache( $object_ids, $object_type );
	}

	$term_meta_ids = $wpdb->get_col( $wpdb->prepare( "SELECT meta_id FROM $wpdb->termmeta WHERE term_id = %d ", $term ) );
	foreach ( $term_meta_ids as $mid ) {
		delete_metadata_by_mid( 'term', $mid );
	}

	/**
	 * Fires immediately before a term taxonomy ID is deleted.
	 *
	 * @since 2.9.0
	 *
	 * @param int $tt_id Term taxonomy ID.
	 */
	do_action( 'delete_term_taxonomy', $tt_id );

	$wpdb->delete( $wpdb->term_taxonomy, array( 'term_taxonomy_id' => $tt_id ) );

	/**
	 * Fires immediately after a term taxonomy ID is deleted.
	 *
	 * @since 2.9.0
	 *
	 * @param int $tt_id Term taxonomy ID.
	 */
	do_action( 'deleted_term_taxonomy', $tt_id );

	// Delete the term if no taxonomies use it.
	if ( ! $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_taxonomy WHERE term_id = %d", $term ) ) ) {
		$wpdb->delete( $wpdb->terms, array( 'term_id' => $term ) );
	}

	clean_term_cache( $term, $taxonomy );

	/**
	 * Fires after a term is deleted from the database and the cache is cleaned.
	 *
	 * The {@see 'delete_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 2.5.0
	 * @since 4.5.0 Introduced the `$object_ids` argument.
	 *
	 * @param int     $term         Term ID.
	 * @param int     $tt_id        Term taxonomy ID.
	 * @param string  $taxonomy     Taxonomy slug.
	 * @param WP_Term $deleted_term Copy of the already-deleted term.
	 * @param array   $object_ids   List of term object IDs.
	 */
	do_action( 'delete_term', $term, $tt_id, $taxonomy, $deleted_term, $object_ids );

	/**
	 * Fires after a term in a specific taxonomy is deleted.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers to the specific
	 * taxonomy the term belonged to.
	 *
	 * Possible hook names include:
	 *
	 *  - `delete_category`
	 *  - `delete_post_tag`
	 *
	 * @since 2.3.0
	 * @since 4.5.0 Introduced the `$object_ids` argument.
	 *
	 * @param int     $term         Term ID.
	 * @param int     $tt_id        Term taxonomy ID.
	 * @param WP_Term $deleted_term Copy of the already-deleted term.
	 * @param array   $object_ids   List of term object IDs.
	 */
	do_action( "delete_{$taxonomy}", $term, $tt_id, $deleted_term, $object_ids );

	return true;
}

/**
 * Deletes one existing category.
 *
 * @since 2.0.0
 *
 * @param int $cat_id Category term ID.
 * @return bool|int|WP_Error Returns true if completes delete action; false if term doesn't exist;
 *                           Zero on attempted deletion of default Category; WP_Error object is
 *                           also a possibility.
 */
function wp_delete_category( $cat_id ) {
	return wp_delete_term( $cat_id, 'category' );
}

/**
 * Retrieves the terms associated with the given object(s), in the supplied taxonomies.
 *
 * @since 2.3.0
 * @since 4.2.0 Added support for 'taxonomy', 'parent', and 'term_taxonomy_id' values of `$orderby`.
 *              Introduced `$parent` argument.
 * @since 4.4.0 Introduced `$meta_query` and `$update_term_meta_cache` arguments. When `$fields` is 'all' or
 *              'all_with_object_id', an array of `WP_Term` objects will be returned.
 * @since 4.7.0 Refactored to use WP_Term_Query, and to support any WP_Term_Query arguments.
 * @since 6.3.0 Passing `update_term_meta_cache` argument value false by default resulting in get_terms() to not
 *              prime the term meta cache.
 *
 * @param int|int[]       $object_ids The ID(s) of the object(s) to retrieve.
 * @param string|string[] $taxonomies The taxonomy names to retrieve terms from.
 * @param array|string    $args       See WP_Term_Query::__construct() for supported arguments.
 * @return WP_Term[]|int[]|string[]|string|WP_Error Array of terms, a count thereof as a numeric string,
 *                                                  or WP_Error if any of the taxonomies do not exist.
 *                                                  See WP_Term_Query::get_terms() for more information.
 */
function wp_get_object_terms( $object_ids, $taxonomies, $args = array() ) {
	if ( empty( $object_ids ) || empty( $taxonomies ) ) {
		return array();
	}

	if ( ! is_array( $taxonomies ) ) {
		$taxonomies = array( $taxonomies );
	}

	foreach ( $taxonomies as $taxonomy ) {
		if ( ! taxonomy_exists( $taxonomy ) ) {
			return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
		}
	}

	if ( ! is_array( $object_ids ) ) {
		$object_ids = array( $object_ids );
	}
	$object_ids = array_map( 'intval', $object_ids );

	$defaults = array(
		'update_term_meta_cache' => false,
	);

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

	/**
	 * Filters arguments for retrieving object terms.
	 *
	 * @since 4.9.0
	 *
	 * @param array    $args       An array of arguments for retrieving terms for the given object(s).
	 *                             See {@see wp_get_object_terms()} for details.
	 * @param int[]    $object_ids Array of object IDs.
	 * @param string[] $taxonomies Array of taxonomy names to retrieve terms from.
	 */
	$args = apply_filters( 'wp_get_object_terms_args', $args, $object_ids, $taxonomies );

	/*
	 * When one or more queried taxonomies is registered with an 'args' array,
	 * those params override the `$args` passed to this function.
	 */
	$terms = array();
	if ( count( $taxonomies ) > 1 ) {
		foreach ( $taxonomies as $index => $taxonomy ) {
			$t = get_taxonomy( $taxonomy );
			if ( isset( $t->args ) && is_array( $t->args ) && array_merge( $args, $t->args ) != $args ) {
				unset( $taxonomies[ $index ] );
				$terms = array_merge( $terms, wp_get_object_terms( $object_ids, $taxonomy, array_merge( $args, $t->args ) ) );
			}
		}
	} else {
		$t = get_taxonomy( $taxonomies[0] );
		if ( isset( $t->args ) && is_array( $t->args ) ) {
			$args = array_merge( $args, $t->args );
		}
	}

	$args['taxonomy']   = $taxonomies;
	$args['object_ids'] = $object_ids;

	// Taxonomies registered without an 'args' param are handled here.
	if ( ! empty( $taxonomies ) ) {
		$terms_from_remaining_taxonomies = get_terms( $args );

		// Array keys should be preserved for values of $fields that use term_id for keys.
		if ( ! empty( $args['fields'] ) && str_starts_with( $args['fields'], 'id=>' ) ) {
			$terms = $terms + $terms_from_remaining_taxonomies;
		} else {
			$terms = array_merge( $terms, $terms_from_remaining_taxonomies );
		}
	}

	/**
	 * Filters the terms for a given object or objects.
	 *
	 * @since 4.2.0
	 *
	 * @param WP_Term[]|int[]|string[]|string $terms      Array of terms or a count thereof as a numeric string.
	 * @param int[]                           $object_ids Array of object IDs for which terms were retrieved.
	 * @param string[]                        $taxonomies Array of taxonomy names from which terms were retrieved.
	 * @param array                           $args       Array of arguments for retrieving terms for the given
	 *                                                    object(s). See wp_get_object_terms() for details.
	 */
	$terms = apply_filters( 'get_object_terms', $terms, $object_ids, $taxonomies, $args );

	$object_ids = implode( ',', $object_ids );
	$taxonomies = "'" . implode( "', '", array_map( 'esc_sql', $taxonomies ) ) . "'";

	/**
	 * Filters the terms for a given object or objects.
	 *
	 * The `$taxonomies` parameter passed to this filter is formatted as a SQL fragment. The
	 * {@see 'get_object_terms'} filter is recommended as an alternative.
	 *
	 * @since 2.8.0
	 *
	 * @param WP_Term[]|int[]|string[]|string $terms      Array of terms or a count thereof as a numeric string.
	 * @param string                          $object_ids Comma separated list of object IDs for which terms were retrieved.
	 * @param string                          $taxonomies SQL fragment of taxonomy names from which terms were retrieved.
	 * @param array                           $args       Array of arguments for retrieving terms for the given
	 *                                                    object(s). See wp_get_object_terms() for details.
	 */
	return apply_filters( 'wp_get_object_terms', $terms, $object_ids, $taxonomies, $args );
}

/**
 * Adds a new term to the database.
 *
 * A non-existent term is inserted in the following sequence:
 * 1. The term is added to the term table, then related to the taxonomy.
 * 2. If everything is correct, several actions are fired.
 * 3. The 'term_id_filter' is evaluated.
 * 4. The term cache is cleaned.
 * 5. Several more actions are fired.
 * 6. An array is returned containing the `term_id` and `term_taxonomy_id`.
 *
 * If the 'slug' argument is not empty, then it is checked to see if the term
 * is invalid. If it is not a valid, existing term, it is added and the term_id
 * is given.
 *
 * If the taxonomy is hierarchical, and the 'parent' argument is not empty,
 * the term is inserted and the term_id will be given.
 *
 * Error handling:
 * If `$taxonomy` does not exist or `$term` is empty,
 * a WP_Error object will be returned.
 *
 * If the term already exists on the same hierarchical level,
 * or the term slug and name are not unique, a WP_Error object will be returned.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @since 2.3.0
 *
 * @param string       $term     The term name to add.
 * @param string       $taxonomy The taxonomy to which to add the term.
 * @param array|string $args {
 *     Optional. Array or query string of arguments for inserting a term.
 *
 *     @type string $alias_of    Slug of the term to make this term an alias of.
 *                               Default empty string. Accepts a term slug.
 *     @type string $description The term description. Default empty string.
 *     @type int    $parent      The id of the parent term. Default 0.
 *     @type string $slug        The term slug to use. Default empty string.
 * }
 * @return array|WP_Error {
 *     An array of the new term data, WP_Error otherwise.
 *
 *     @type int        $term_id          The new term ID.
 *     @type int|string $term_taxonomy_id The new term taxonomy ID. Can be a numeric string.
 * }
 */
function wp_insert_term( $term, $taxonomy, $args = array() ) {
	global $wpdb;

	if ( ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	/**
	 * Filters a term before it is sanitized and inserted into the database.
	 *
	 * @since 3.0.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param string|WP_Error $term     The term name to add, or a WP_Error object if there's an error.
	 * @param string          $taxonomy Taxonomy slug.
	 * @param array|string    $args     Array or query string of arguments passed to wp_insert_term().
	 */
	$term = apply_filters( 'pre_insert_term', $term, $taxonomy, $args );

	if ( is_wp_error( $term ) ) {
		return $term;
	}

	if ( is_int( $term ) && 0 === $term ) {
		return new WP_Error( 'invalid_term_id', __( 'Invalid term ID.' ) );
	}

	if ( '' === trim( $term ) ) {
		return new WP_Error( 'empty_term_name', __( 'A name is required for this term.' ) );
	}

	$defaults = array(
		'alias_of'    => '',
		'description' => '',
		'parent'      => 0,
		'slug'        => '',
	);
	$args     = wp_parse_args( $args, $defaults );

	if ( (int) $args['parent'] > 0 && ! term_exists( (int) $args['parent'] ) ) {
		return new WP_Error( 'missing_parent', __( 'Parent term does not exist.' ) );
	}

	$args['name']     = $term;
	$args['taxonomy'] = $taxonomy;

	// Coerce null description to strings, to avoid database errors.
	$args['description'] = (string) $args['description'];

	$args = sanitize_term( $args, $taxonomy, 'db' );

	// expected_slashed ($name)
	$name        = wp_unslash( $args['name'] );
	$description = wp_unslash( $args['description'] );
	$parent      = (int) $args['parent'];

	$slug_provided = ! empty( $args['slug'] );
	if ( ! $slug_provided ) {
		$slug = sanitize_title( $name );
	} else {
		$slug = $args['slug'];
	}

	$term_group = 0;
	if ( $args['alias_of'] ) {
		$alias = get_term_by( 'slug', $args['alias_of'], $taxonomy );
		if ( ! empty( $alias->term_group ) ) {
			// The alias we want is already in a group, so let's use that one.
			$term_group = $alias->term_group;
		} elseif ( ! empty( $alias->term_id ) ) {
			/*
			 * The alias is not in a group, so we create a new one
			 * and add the alias to it.
			 */
			$term_group = $wpdb->get_var( "SELECT MAX(term_group) FROM $wpdb->terms" ) + 1;

			wp_update_term(
				$alias->term_id,
				$taxonomy,
				array(
					'term_group' => $term_group,
				)
			);
		}
	}

	/*
	 * Prevent the creation of terms with duplicate names at the same level of a taxonomy hierarchy,
	 * unless a unique slug has been explicitly provided.
	 */
	$name_matches = get_terms(
		array(
			'taxonomy'               => $taxonomy,
			'name'                   => $name,
			'hide_empty'             => false,
			'parent'                 => $args['parent'],
			'update_term_meta_cache' => false,
		)
	);

	/*
	 * The `name` match in `get_terms()` doesn't differentiate accented characters,
	 * so we do a stricter comparison here.
	 */
	$name_match = null;
	if ( $name_matches ) {
		foreach ( $name_matches as $_match ) {
			if ( strtolower( $name ) === strtolower( $_match->name ) ) {
				$name_match = $_match;
				break;
			}
		}
	}

	if ( $name_match ) {
		$slug_match = get_term_by( 'slug', $slug, $taxonomy );
		if ( ! $slug_provided || $name_match->slug === $slug || $slug_match ) {
			if ( is_taxonomy_hierarchical( $taxonomy ) ) {
				$siblings = get_terms(
					array(
						'taxonomy'               => $taxonomy,
						'get'                    => 'all',
						'parent'                 => $parent,
						'update_term_meta_cache' => false,
					)
				);

				$existing_term = null;
				$sibling_names = wp_list_pluck( $siblings, 'name' );
				$sibling_slugs = wp_list_pluck( $siblings, 'slug' );

				if ( ( ! $slug_provided || $name_match->slug === $slug ) && in_array( $name, $sibling_names, true ) ) {
					$existing_term = $name_match;
				} elseif ( $slug_match && in_array( $slug, $sibling_slugs, true ) ) {
					$existing_term = $slug_match;
				}

				if ( $existing_term ) {
					return new WP_Error( 'term_exists', __( 'A term with the name provided already exists with this parent.' ), $existing_term->term_id );
				}
			} else {
				return new WP_Error( 'term_exists', __( 'A term with the name provided already exists in this taxonomy.' ), $name_match->term_id );
			}
		}
	}

	$slug = wp_unique_term_slug( $slug, (object) $args );

	$data = compact( 'name', 'slug', 'term_group' );

	/**
	 * Filters term data before it is inserted into the database.
	 *
	 * @since 4.7.0
	 *
	 * @param array  $data     Term data to be inserted.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_insert_term().
	 */
	$data = apply_filters( 'wp_insert_term_data', $data, $taxonomy, $args );

	if ( false === $wpdb->insert( $wpdb->terms, $data ) ) {
		return new WP_Error( 'db_insert_error', __( 'Could not insert term into the database.' ), $wpdb->last_error );
	}

	$term_id = (int) $wpdb->insert_id;

	// Seems unreachable. However, is used in the case that a term name is provided, which sanitizes to an empty string.
	if ( empty( $slug ) ) {
		$slug = sanitize_title( $slug, $term_id );

		/** This action is documented in wp-includes/taxonomy.php */
		do_action( 'edit_terms', $term_id, $taxonomy );
		$wpdb->update( $wpdb->terms, compact( 'slug' ), compact( 'term_id' ) );

		/** This action is documented in wp-includes/taxonomy.php */
		do_action( 'edited_terms', $term_id, $taxonomy );
	}

	$tt_id = $wpdb->get_var( $wpdb->prepare( "SELECT tt.term_taxonomy_id FROM $wpdb->term_taxonomy AS tt INNER JOIN $wpdb->terms AS t ON tt.term_id = t.term_id WHERE tt.taxonomy = %s AND t.term_id = %d", $taxonomy, $term_id ) );

	if ( ! empty( $tt_id ) ) {
		return array(
			'term_id'          => $term_id,
			'term_taxonomy_id' => $tt_id,
		);
	}

	if ( false === $wpdb->insert( $wpdb->term_taxonomy, compact( 'term_id', 'taxonomy', 'description', 'parent' ) + array( 'count' => 0 ) ) ) {
		return new WP_Error( 'db_insert_error', __( 'Could not insert term taxonomy into the database.' ), $wpdb->last_error );
	}

	$tt_id = (int) $wpdb->insert_id;

	/*
	 * Sanity check: if we just created a term with the same parent + taxonomy + slug but a higher term_id than
	 * an existing term, then we have unwittingly created a duplicate term. Delete the dupe, and use the term_id
	 * and term_taxonomy_id of the older term instead. Then return out of the function so that the "create" hooks
	 * are not fired.
	 */
	$duplicate_term = $wpdb->get_row( $wpdb->prepare( "SELECT t.term_id, t.slug, tt.term_taxonomy_id, tt.taxonomy FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy AS tt ON ( tt.term_id = t.term_id ) WHERE t.slug = %s AND tt.parent = %d AND tt.taxonomy = %s AND t.term_id < %d AND tt.term_taxonomy_id != %d", $slug, $parent, $taxonomy, $term_id, $tt_id ) );

	/**
	 * Filters the duplicate term check that takes place during term creation.
	 *
	 * Term parent + taxonomy + slug combinations are meant to be unique, and wp_insert_term()
	 * performs a last-minute confirmation of this uniqueness before allowing a new term
	 * to be created. Plugins with different uniqueness requirements may use this filter
	 * to bypass or modify the duplicate-term check.
	 *
	 * @since 5.1.0
	 *
	 * @param object $duplicate_term Duplicate term row from terms table, if found.
	 * @param string $term           Term being inserted.
	 * @param string $taxonomy       Taxonomy name.
	 * @param array  $args           Arguments passed to wp_insert_term().
	 * @param int    $tt_id          term_taxonomy_id for the newly created term.
	 */
	$duplicate_term = apply_filters( 'wp_insert_term_duplicate_term_check', $duplicate_term, $term, $taxonomy, $args, $tt_id );

	if ( $duplicate_term ) {
		$wpdb->delete( $wpdb->terms, array( 'term_id' => $term_id ) );
		$wpdb->delete( $wpdb->term_taxonomy, array( 'term_taxonomy_id' => $tt_id ) );

		$term_id = (int) $duplicate_term->term_id;
		$tt_id   = (int) $duplicate_term->term_taxonomy_id;

		clean_term_cache( $term_id, $taxonomy );
		return array(
			'term_id'          => $term_id,
			'term_taxonomy_id' => $tt_id,
		);
	}

	/**
	 * Fires immediately after a new term is created, before the term cache is cleaned.
	 *
	 * The {@see 'create_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_insert_term().
	 */
	do_action( 'create_term', $term_id, $tt_id, $taxonomy, $args );

	/**
	 * Fires after a new term is created for a specific taxonomy.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers
	 * to the slug of the taxonomy the term was created for.
	 *
	 * Possible hook names include:
	 *
	 *  - `create_category`
	 *  - `create_post_tag`
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int   $term_id Term ID.
	 * @param int   $tt_id   Term taxonomy ID.
	 * @param array $args    Arguments passed to wp_insert_term().
	 */
	do_action( "create_{$taxonomy}", $term_id, $tt_id, $args );

	/**
	 * Filters the term ID after a new term is created.
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int   $term_id Term ID.
	 * @param int   $tt_id   Term taxonomy ID.
	 * @param array $args    Arguments passed to wp_insert_term().
	 */
	$term_id = apply_filters( 'term_id_filter', $term_id, $tt_id, $args );

	clean_term_cache( $term_id, $taxonomy );

	/**
	 * Fires after a new term is created, and after the term cache has been cleaned.
	 *
	 * The {@see 'created_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_insert_term().
	 */
	do_action( 'created_term', $term_id, $tt_id, $taxonomy, $args );

	/**
	 * Fires after a new term in a specific taxonomy is created, and after the term
	 * cache has been cleaned.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers to the taxonomy slug.
	 *
	 * Possible hook names include:
	 *
	 *  - `created_category`
	 *  - `created_post_tag`
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int   $term_id Term ID.
	 * @param int   $tt_id   Term taxonomy ID.
	 * @param array $args    Arguments passed to wp_insert_term().
	 */
	do_action( "created_{$taxonomy}", $term_id, $tt_id, $args );

	/**
	 * Fires after a term has been saved, and the term cache has been cleared.
	 *
	 * The {@see 'saved_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 5.5.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param bool   $update   Whether this is an existing term being updated.
	 * @param array  $args     Arguments passed to wp_insert_term().
	 */
	do_action( 'saved_term', $term_id, $tt_id, $taxonomy, false, $args );

	/**
	 * Fires after a term in a specific taxonomy has been saved, and the term
	 * cache has been cleared.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers to the taxonomy slug.
	 *
	 * Possible hook names include:
	 *
	 *  - `saved_category`
	 *  - `saved_post_tag`
	 *
	 * @since 5.5.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int   $term_id Term ID.
	 * @param int   $tt_id   Term taxonomy ID.
	 * @param bool  $update  Whether this is an existing term being updated.
	 * @param array $args    Arguments passed to wp_insert_term().
	 */
	do_action( "saved_{$taxonomy}", $term_id, $tt_id, false, $args );

	return array(
		'term_id'          => $term_id,
		'term_taxonomy_id' => $tt_id,
	);
}

/**
 * Creates term and taxonomy relationships.
 *
 * Relates an object (post, link, etc.) to a term and taxonomy type. Creates the
 * term and taxonomy relationship if it doesn't already exist. Creates a term if
 * it doesn't exist (using the slug).
 *
 * A relationship means that the term is grouped in or belongs to the taxonomy.
 * A term has no meaning until it is given context by defining which taxonomy it
 * exists under.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int              $object_id The object to relate to.
 * @param string|int|array $terms     A single term slug, single term ID, or array of either term slugs or IDs.
 *                                    Will replace all existing related terms in this taxonomy. Passing an
 *                                    empty array will remove all related terms.
 * @param string           $taxonomy  The context in which to relate the term to the object.
 * @param bool             $append    Optional. If false will delete difference of terms. Default false.
 * @return array|WP_Error Term taxonomy IDs of the affected terms or WP_Error on failure.
 */
function wp_set_object_terms( $object_id, $terms, $taxonomy, $append = false ) {
	global $wpdb;

	$object_id = (int) $object_id;

	if ( ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	if ( empty( $terms ) ) {
		$terms = array();
	} elseif ( ! is_array( $terms ) ) {
		$terms = array( $terms );
	}

	if ( ! $append ) {
		$old_tt_ids = wp_get_object_terms(
			$object_id,
			$taxonomy,
			array(
				'fields'                 => 'tt_ids',
				'orderby'                => 'none',
				'update_term_meta_cache' => false,
			)
		);
	} else {
		$old_tt_ids = array();
	}

	$tt_ids     = array();
	$term_ids   = array();
	$new_tt_ids = array();

	foreach ( (array) $terms as $term ) {
		if ( '' === trim( $term ) ) {
			continue;
		}

		$term_info = term_exists( $term, $taxonomy );

		if ( ! $term_info ) {
			// Skip if a non-existent term ID is passed.
			if ( is_int( $term ) ) {
				continue;
			}

			$term_info = wp_insert_term( $term, $taxonomy );
		}

		if ( is_wp_error( $term_info ) ) {
			return $term_info;
		}

		$term_ids[] = $term_info['term_id'];
		$tt_id      = $term_info['term_taxonomy_id'];
		$tt_ids[]   = $tt_id;

		if ( $wpdb->get_var( $wpdb->prepare( "SELECT term_taxonomy_id FROM $wpdb->term_relationships WHERE object_id = %d AND term_taxonomy_id = %d", $object_id, $tt_id ) ) ) {
			continue;
		}

		/**
		 * Fires immediately before an object-term relationship is added.
		 *
		 * @since 2.9.0
		 * @since 4.7.0 Added the `$taxonomy` parameter.
		 *
		 * @param int    $object_id Object ID.
		 * @param int    $tt_id     Term taxonomy ID.
		 * @param string $taxonomy  Taxonomy slug.
		 */
		do_action( 'add_term_relationship', $object_id, $tt_id, $taxonomy );

		$wpdb->insert(
			$wpdb->term_relationships,
			array(
				'object_id'        => $object_id,
				'term_taxonomy_id' => $tt_id,
			)
		);

		/**
		 * Fires immediately after an object-term relationship is added.
		 *
		 * @since 2.9.0
		 * @since 4.7.0 Added the `$taxonomy` parameter.
		 *
		 * @param int    $object_id Object ID.
		 * @param int    $tt_id     Term taxonomy ID.
		 * @param string $taxonomy  Taxonomy slug.
		 */
		do_action( 'added_term_relationship', $object_id, $tt_id, $taxonomy );

		$new_tt_ids[] = $tt_id;
	}

	if ( $new_tt_ids ) {
		wp_update_term_count( $new_tt_ids, $taxonomy );
	}

	if ( ! $append ) {
		$delete_tt_ids = array_diff( $old_tt_ids, $tt_ids );

		if ( $delete_tt_ids ) {
			$in_delete_tt_ids = "'" . implode( "', '", $delete_tt_ids ) . "'";
			$delete_term_ids  = $wpdb->get_col( $wpdb->prepare( "SELECT tt.term_id FROM $wpdb->term_taxonomy AS tt WHERE tt.taxonomy = %s AND tt.term_taxonomy_id IN ($in_delete_tt_ids)", $taxonomy ) );
			$delete_term_ids  = array_map( 'intval', $delete_term_ids );

			$remove = wp_remove_object_terms( $object_id, $delete_term_ids, $taxonomy );
			if ( is_wp_error( $remove ) ) {
				return $remove;
			}
		}
	}

	$t = get_taxonomy( $taxonomy );

	if ( ! $append && isset( $t->sort ) && $t->sort ) {
		$values     = array();
		$term_order = 0;

		$final_tt_ids = wp_get_object_terms(
			$object_id,
			$taxonomy,
			array(
				'fields'                 => 'tt_ids',
				'update_term_meta_cache' => false,
			)
		);

		foreach ( $tt_ids as $tt_id ) {
			if ( in_array( (int) $tt_id, $final_tt_ids, true ) ) {
				$values[] = $wpdb->prepare( '(%d, %d, %d)', $object_id, $tt_id, ++$term_order );
			}
		}

		if ( $values ) {
			if ( false === $wpdb->query( "INSERT INTO $wpdb->term_relationships (object_id, term_taxonomy_id, term_order) VALUES " . implode( ',', $values ) . ' ON DUPLICATE KEY UPDATE term_order = VALUES(term_order)' ) ) {
				return new WP_Error( 'db_insert_error', __( 'Could not insert term relationship into the database.' ), $wpdb->last_error );
			}
		}
	}

	wp_cache_delete( $object_id, $taxonomy . '_relationships' );
	wp_cache_set_terms_last_changed();

	/**
	 * Fires after an object's terms have been set.
	 *
	 * @since 2.8.0
	 *
	 * @param int    $object_id  Object ID.
	 * @param array  $terms      An array of object term IDs or slugs.
	 * @param array  $tt_ids     An array of term taxonomy IDs.
	 * @param string $taxonomy   Taxonomy slug.
	 * @param bool   $append     Whether to append new terms to the old terms.
	 * @param array  $old_tt_ids Old array of term taxonomy IDs.
	 */
	do_action( 'set_object_terms', $object_id, $terms, $tt_ids, $taxonomy, $append, $old_tt_ids );

	return $tt_ids;
}

/**
 * Adds term(s) associated with a given object.
 *
 * @since 3.6.0
 *
 * @param int              $object_id The ID of the object to which the terms will be added.
 * @param string|int|array $terms     The slug(s) or ID(s) of the term(s) to add.
 * @param array|string     $taxonomy  Taxonomy name.
 * @return array|WP_Error Term taxonomy IDs of the affected terms.
 */
function wp_add_object_terms( $object_id, $terms, $taxonomy ) {
	return wp_set_object_terms( $object_id, $terms, $taxonomy, true );
}

/**
 * Removes term(s) associated with a given object.
 *
 * @since 3.6.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int              $object_id The ID of the object from which the terms will be removed.
 * @param string|int|array $terms     The slug(s) or ID(s) of the term(s) to remove.
 * @param string           $taxonomy  Taxonomy name.
 * @return bool|WP_Error True on success, false or WP_Error on failure.
 */
function wp_remove_object_terms( $object_id, $terms, $taxonomy ) {
	global $wpdb;

	$object_id = (int) $object_id;

	if ( ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	if ( ! is_array( $terms ) ) {
		$terms = array( $terms );
	}

	$tt_ids = array();

	foreach ( (array) $terms as $term ) {
		if ( '' === trim( $term ) ) {
			continue;
		}

		$term_info = term_exists( $term, $taxonomy );
		if ( ! $term_info ) {
			// Skip if a non-existent term ID is passed.
			if ( is_int( $term ) ) {
				continue;
			}
		}

		if ( is_wp_error( $term_info ) ) {
			return $term_info;
		}

		$tt_ids[] = $term_info['term_taxonomy_id'];
	}

	if ( $tt_ids ) {
		$in_tt_ids = "'" . implode( "', '", $tt_ids ) . "'";

		/**
		 * Fires immediately before an object-term relationship is deleted.
		 *
		 * @since 2.9.0
		 * @since 4.7.0 Added the `$taxonomy` parameter.
		 *
		 * @param int    $object_id Object ID.
		 * @param array  $tt_ids    An array of term taxonomy IDs.
		 * @param string $taxonomy  Taxonomy slug.
		 */
		do_action( 'delete_term_relationships', $object_id, $tt_ids, $taxonomy );

		$deleted = $wpdb->query( $wpdb->prepare( "DELETE FROM $wpdb->term_relationships WHERE object_id = %d AND term_taxonomy_id IN ($in_tt_ids)", $object_id ) );

		wp_cache_delete( $object_id, $taxonomy . '_relationships' );
		wp_cache_set_terms_last_changed();

		/**
		 * Fires immediately after an object-term relationship is deleted.
		 *
		 * @since 2.9.0
		 * @since 4.7.0 Added the `$taxonomy` parameter.
		 *
		 * @param int    $object_id Object ID.
		 * @param array  $tt_ids    An array of term taxonomy IDs.
		 * @param string $taxonomy  Taxonomy slug.
		 */
		do_action( 'deleted_term_relationships', $object_id, $tt_ids, $taxonomy );

		wp_update_term_count( $tt_ids, $taxonomy );

		return (bool) $deleted;
	}

	return false;
}

/**
 * Makes term slug unique, if it isn't already.
 *
 * The `$slug` has to be unique global to every taxonomy, meaning that one
 * taxonomy term can't have a matching slug with another taxonomy term. Each
 * slug has to be globally unique for every taxonomy.
 *
 * The way this works is that if the taxonomy that the term belongs to is
 * hierarchical and has a parent, it will append that parent to the $slug.
 *
 * If that still doesn't return a unique slug, then it tries to append a number
 * until it finds a number that is truly unique.
 *
 * The only purpose for `$term` is for appending a parent, if one exists.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $slug The string that will be tried for a unique slug.
 * @param object $term The term object that the `$slug` will belong to.
 * @return string Will return a true unique slug.
 */
function wp_unique_term_slug( $slug, $term ) {
	global $wpdb;

	$needs_suffix  = true;
	$original_slug = $slug;

	// As of 4.1, duplicate slugs are allowed as long as they're in different taxonomies.
	if ( ! term_exists( $slug ) || get_option( 'db_version' ) >= 30133 && ! get_term_by( 'slug', $slug, $term->taxonomy ) ) {
		$needs_suffix = false;
	}

	/*
	 * If the taxonomy supports hierarchy and the term has a parent, make the slug unique
	 * by incorporating parent slugs.
	 */
	$parent_suffix = '';
	if ( $needs_suffix && is_taxonomy_hierarchical( $term->taxonomy ) && ! empty( $term->parent ) ) {
		$the_parent = $term->parent;
		while ( ! empty( $the_parent ) ) {
			$parent_term = get_term( $the_parent, $term->taxonomy );
			if ( is_wp_error( $parent_term ) || empty( $parent_term ) ) {
				break;
			}
			$parent_suffix .= '-' . $parent_term->slug;
			if ( ! term_exists( $slug . $parent_suffix ) ) {
				break;
			}

			if ( empty( $parent_term->parent ) ) {
				break;
			}
			$the_parent = $parent_term->parent;
		}
	}

	// If we didn't get a unique slug, try appending a number to make it unique.

	/**
	 * Filters whether the proposed unique term slug is bad.
	 *
	 * @since 4.3.0
	 *
	 * @param bool   $needs_suffix Whether the slug needs to be made unique with a suffix.
	 * @param string $slug         The slug.
	 * @param object $term         Term object.
	 */
	if ( apply_filters( 'wp_unique_term_slug_is_bad_slug', $needs_suffix, $slug, $term ) ) {
		if ( $parent_suffix ) {
			$slug .= $parent_suffix;
		}

		if ( ! empty( $term->term_id ) ) {
			$query = $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s AND term_id != %d", $slug, $term->term_id );
		} else {
			$query = $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s", $slug );
		}

		if ( $wpdb->get_var( $query ) ) { // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
			$num = 2;
			do {
				$alt_slug = $slug . "-$num";
				++$num;
				$slug_check = $wpdb->get_var( $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s", $alt_slug ) );
			} while ( $slug_check );
			$slug = $alt_slug;
		}
	}

	/**
	 * Filters the unique term slug.
	 *
	 * @since 4.3.0
	 *
	 * @param string $slug          Unique term slug.
	 * @param object $term          Term object.
	 * @param string $original_slug Slug originally passed to the function for testing.
	 */
	return apply_filters( 'wp_unique_term_slug', $slug, $term, $original_slug );
}

/**
 * Updates term based on arguments provided.
 *
 * The `$args` will indiscriminately override all values with the same field name.
 * Care must be taken to not override important information need to update or
 * update will fail (or perhaps create a new term, neither would be acceptable).
 *
 * Defaults will set 'alias_of', 'description', 'parent', and 'slug' if not
 * defined in `$args` already.
 *
 * 'alias_of' will create a term group, if it doesn't already exist, and
 * update it for the `$term`.
 *
 * If the 'slug' argument in `$args` is missing, then the 'name' will be used.
 * If you set 'slug' and it isn't unique, then a WP_Error is returned.
 * If you don't pass any slug, then a unique one will be created.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int          $term_id  The ID of the term.
 * @param string       $taxonomy The taxonomy of the term.
 * @param array        $args {
 *     Optional. Array of arguments for updating a term.
 *
 *     @type string $alias_of    Slug of the term to make this term an alias of.
 *                               Default empty string. Accepts a term slug.
 *     @type string $description The term description. Default empty string.
 *     @type int    $parent      The id of the parent term. Default 0.
 *     @type string $slug        The term slug to use. Default empty string.
 * }
 * @return array|WP_Error An array containing the `term_id` and `term_taxonomy_id`,
 *                        WP_Error otherwise.
 */
function wp_update_term( $term_id, $taxonomy, $args = array() ) {
	global $wpdb;

	if ( ! taxonomy_exists( $taxonomy ) ) {
		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
	}

	$term_id = (int) $term_id;

	// First, get all of the original args.
	$term = get_term( $term_id, $taxonomy );

	if ( is_wp_error( $term ) ) {
		return $term;
	}

	if ( ! $term ) {
		return new WP_Error( 'invalid_term', __( 'Empty Term.' ) );
	}

	$term = (array) $term->data;

	// Escape data pulled from DB.
	$term = wp_slash( $term );

	// Merge old and new args with new args overwriting old ones.
	$args = array_merge( $term, $args );

	$defaults    = array(
		'alias_of'    => '',
		'description' => '',
		'parent'      => 0,
		'slug'        => '',
	);
	$args        = wp_parse_args( $args, $defaults );
	$args        = sanitize_term( $args, $taxonomy, 'db' );
	$parsed_args = $args;

	// expected_slashed ($name)
	$name        = wp_unslash( $args['name'] );
	$description = wp_unslash( $args['description'] );

	$parsed_args['name']        = $name;
	$parsed_args['description'] = $description;

	if ( '' === trim( $name ) ) {
		return new WP_Error( 'empty_term_name', __( 'A name is required for this term.' ) );
	}

	if ( (int) $parsed_args['parent'] > 0 && ! term_exists( (int) $parsed_args['parent'] ) ) {
		return new WP_Error( 'missing_parent', __( 'Parent term does not exist.' ) );
	}

	$empty_slug = false;
	if ( empty( $args['slug'] ) ) {
		$empty_slug = true;
		$slug       = sanitize_title( $name );
	} else {
		$slug = $args['slug'];
	}

	$parsed_args['slug'] = $slug;

	$term_group = isset( $parsed_args['term_group'] ) ? $parsed_args['term_group'] : 0;
	if ( $args['alias_of'] ) {
		$alias = get_term_by( 'slug', $args['alias_of'], $taxonomy );
		if ( ! empty( $alias->term_group ) ) {
			// The alias we want is already in a group, so let's use that one.
			$term_group = $alias->term_group;
		} elseif ( ! empty( $alias->term_id ) ) {
			/*
			 * The alias is not in a group, so we create a new one
			 * and add the alias to it.
			 */
			$term_group = $wpdb->get_var( "SELECT MAX(term_group) FROM $wpdb->terms" ) + 1;

			wp_update_term(
				$alias->term_id,
				$taxonomy,
				array(
					'term_group' => $term_group,
				)
			);
		}

		$parsed_args['term_group'] = $term_group;
	}

	/**
	 * Filters the term parent.
	 *
	 * Hook to this filter to see if it will cause a hierarchy loop.
	 *
	 * @since 3.1.0
	 *
	 * @param int    $parent_term ID of the parent term.
	 * @param int    $term_id     Term ID.
	 * @param string $taxonomy    Taxonomy slug.
	 * @param array  $parsed_args An array of potentially altered update arguments for the given term.
	 * @param array  $args        Arguments passed to wp_update_term().
	 */
	$parent = (int) apply_filters( 'wp_update_term_parent', $args['parent'], $term_id, $taxonomy, $parsed_args, $args );

	// Check for duplicate slug.
	$duplicate = get_term_by( 'slug', $slug, $taxonomy );
	if ( $duplicate && $duplicate->term_id !== $term_id ) {
		/*
		 * If an empty slug was passed or the parent changed, reset the slug to something unique.
		 * Otherwise, bail.
		 */
		if ( $empty_slug || ( $parent !== (int) $term['parent'] ) ) {
			$slug = wp_unique_term_slug( $slug, (object) $args );
		} else {
			/* translators: %s: Taxonomy term slug. */
			return new WP_Error( 'duplicate_term_slug', sprintf( __( 'The slug &#8220;%s&#8221; is already in use by another term.' ), $slug ) );
		}
	}

	$tt_id = (int) $wpdb->get_var( $wpdb->prepare( "SELECT tt.term_taxonomy_id FROM $wpdb->term_taxonomy AS tt INNER JOIN $wpdb->terms AS t ON tt.term_id = t.term_id WHERE tt.taxonomy = %s AND t.term_id = %d", $taxonomy, $term_id ) );

	// Check whether this is a shared term that needs splitting.
	$_term_id = _split_shared_term( $term_id, $tt_id );
	if ( ! is_wp_error( $_term_id ) ) {
		$term_id = $_term_id;
	}

	/**
	 * Fires immediately before the given terms are edited.
	 *
	 * @since 2.9.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	do_action( 'edit_terms', $term_id, $taxonomy, $args );

	$data = compact( 'name', 'slug', 'term_group' );

	/**
	 * Filters term data before it is updated in the database.
	 *
	 * @since 4.7.0
	 *
	 * @param array  $data     Term data to be updated.
	 * @param int    $term_id  Term ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	$data = apply_filters( 'wp_update_term_data', $data, $term_id, $taxonomy, $args );

	$wpdb->update( $wpdb->terms, $data, compact( 'term_id' ) );

	if ( empty( $slug ) ) {
		$slug = sanitize_title( $name, $term_id );
		$wpdb->update( $wpdb->terms, compact( 'slug' ), compact( 'term_id' ) );
	}

	/**
	 * Fires immediately after a term is updated in the database, but before its
	 * term-taxonomy relationship is updated.
	 *
	 * @since 2.9.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	do_action( 'edited_terms', $term_id, $taxonomy, $args );

	/**
	 * Fires immediate before a term-taxonomy relationship is updated.
	 *
	 * @since 2.9.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	do_action( 'edit_term_taxonomy', $tt_id, $taxonomy, $args );

	$wpdb->update( $wpdb->term_taxonomy, compact( 'term_id', 'taxonomy', 'description', 'parent' ), array( 'term_taxonomy_id' => $tt_id ) );

	/**
	 * Fires immediately after a term-taxonomy relationship is updated.
	 *
	 * @since 2.9.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	do_action( 'edited_term_taxonomy', $tt_id, $taxonomy, $args );

	/**
	 * Fires after a term has been updated, but before the term cache has been cleaned.
	 *
	 * The {@see 'edit_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	do_action( 'edit_term', $term_id, $tt_id, $taxonomy, $args );

	/**
	 * Fires after a term in a specific taxonomy has been updated, but before the term
	 * cache has been cleaned.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers to the taxonomy slug.
	 *
	 * Possible hook names include:
	 *
	 *  - `edit_category`
	 *  - `edit_post_tag`
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int   $term_id Term ID.
	 * @param int   $tt_id   Term taxonomy ID.
	 * @param array $args    Arguments passed to wp_update_term().
	 */
	do_action( "edit_{$taxonomy}", $term_id, $tt_id, $args );

	/** This filter is documented in wp-includes/taxonomy.php */
	$term_id = apply_filters( 'term_id_filter', $term_id, $tt_id );

	clean_term_cache( $term_id, $taxonomy );

	/**
	 * Fires after a term has been updated, and the term cache has been cleaned.
	 *
	 * The {@see 'edited_$taxonomy'} hook is also available for targeting a specific
	 * taxonomy.
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int    $term_id  Term ID.
	 * @param int    $tt_id    Term taxonomy ID.
	 * @param string $taxonomy Taxonomy slug.
	 * @param array  $args     Arguments passed to wp_update_term().
	 */
	do_action( 'edited_term', $term_id, $tt_id, $taxonomy, $args );

	/**
	 * Fires after a term for a specific taxonomy has been updated, and the term
	 * cache has been cleaned.
	 *
	 * The dynamic portion of the hook name, `$taxonomy`, refers to the taxonomy slug.
	 *
	 * Possible hook names include:
	 *
	 *  - `edited_category`
	 *  - `edited_post_tag`
	 *
	 * @since 2.3.0
	 * @since 6.1.0 The `$args` parameter was added.
	 *
	 * @param int   $term_id Term ID.
	 * @param int   $tt_id   Term taxonomy ID.
	 * @param array $args    Arguments passed to wp_update_term().
	 */
	do_action( "edited_{$taxonomy}", $term_id, $tt_id, $args );

	/** This action is documented in wp-includes/taxonomy.php */
	do_action( 'saved_term', $term_id, $tt_id, $taxonomy, true, $args );

	/** This action is documented in wp-includes/taxonomy.php */
	do_action( "saved_{$taxonomy}", $term_id, $tt_id, true, $args );

	return array(
		'term_id'          => $term_id,
		'term_taxonomy_id' => $tt_id,
	);
}

/**
 * Enables or disables term counting.
 *
 * @since 2.5.0
 *
 * @param bool $defer Optional. Enable if true, disable if false.
 * @return bool Whether term counting is enabled or disabled.
 */
function wp_defer_term_counting( $defer = null ) {
	static $_defer = false;

	if ( is_bool( $defer ) ) {
		$_defer = $defer;
		// Flush any deferred counts.
		if ( ! $defer ) {
			wp_update_term_count( null, null, true );
		}
	}

	return $_defer;
}

/**
 * Updates the amount of terms in taxonomy.
 *
 * If there is a taxonomy callback applied, then it will be called for updating
 * the count.
 *
 * The default action is to count what the amount of terms have the relationship
 * of term ID. Once that is done, then update the database.
 *
 * @since 2.3.0
 *
 * @param int|array $terms       The term_taxonomy_id of the terms.
 * @param string    $taxonomy    The context of the term.
 * @param bool      $do_deferred Whether to flush the deferred term counts too. Default false.
 * @return bool If no terms will return false, and if successful will return true.
 */
function wp_update_term_count( $terms, $taxonomy, $do_deferred = false ) {
	static $_deferred = array();

	if ( $do_deferred ) {
		foreach ( (array) array_keys( $_deferred ) as $tax ) {
			wp_update_term_count_now( $_deferred[ $tax ], $tax );
			unset( $_deferred[ $tax ] );
		}
	}

	if ( empty( $terms ) ) {
		return false;
	}

	if ( ! is_array( $terms ) ) {
		$terms = array( $terms );
	}

	if ( wp_defer_term_counting() ) {
		if ( ! isset( $_deferred[ $taxonomy ] ) ) {
			$_deferred[ $taxonomy ] = array();
		}
		$_deferred[ $taxonomy ] = array_unique( array_merge( $_deferred[ $taxonomy ], $terms ) );
		return true;
	}

	return wp_update_term_count_now( $terms, $taxonomy );
}

/**
 * Performs term count update immediately.
 *
 * @since 2.5.0
 *
 * @param array  $terms    The term_taxonomy_id of terms to update.
 * @param string $taxonomy The context of the term.
 * @return true Always true when complete.
 */
function wp_update_term_count_now( $terms, $taxonomy ) {
	$terms = array_map( 'intval', $terms );

	$taxonomy = get_taxonomy( $taxonomy );
	if ( ! empty( $taxonomy->update_count_callback ) ) {
		call_user_func( $taxonomy->update_count_callback, $terms, $taxonomy );
	} else {
		$object_types = (array) $taxonomy->object_type;
		foreach ( $object_types as &$object_type ) {
			if ( str_starts_with( $object_type, 'attachment:' ) ) {
				list( $object_type ) = explode( ':', $object_type );
			}
		}

		if ( array_filter( $object_types, 'post_type_exists' ) == $object_types ) {
			// Only post types are attached to this taxonomy.
			_update_post_term_count( $terms, $taxonomy );
		} else {
			// Default count updater.
			_update_generic_term_count( $terms, $taxonomy );
		}
	}

	clean_term_cache( $terms, '', false );

	return true;
}

//
// Cache.
//

/**
 * Removes the taxonomy relationship to terms from the cache.
 *
 * Will remove the entire taxonomy relationship containing term `$object_id`. The
 * term IDs have to exist within the taxonomy `$object_type` for the deletion to
 * take place.
 *
 * @since 2.3.0
 *
 * @global bool $_wp_suspend_cache_invalidation
 *
 * @see get_object_taxonomies() for more on $object_type.
 *
 * @param int|array    $object_ids  Single or list of term object ID(s).
 * @param array|string $object_type The taxonomy object type.
 */
function clean_object_term_cache( $object_ids, $object_type ) {
	global $_wp_suspend_cache_invalidation;

	if ( ! empty( $_wp_suspend_cache_invalidation ) ) {
		return;
	}

	if ( ! is_array( $object_ids ) ) {
		$object_ids = array( $object_ids );
	}

	$taxonomies = get_object_taxonomies( $object_type );

	foreach ( $taxonomies as $taxonomy ) {
		wp_cache_delete_multiple( $object_ids, "{$taxonomy}_relationships" );
	}

	wp_cache_set_terms_last_changed();

	/**
	 * Fires after the object term cache has been cleaned.
	 *
	 * @since 2.5.0
	 *
	 * @param array  $object_ids An array of object IDs.
	 * @param string $object_type Object type.
	 */
	do_action( 'clean_object_term_cache', $object_ids, $object_type );
}

/**
 * Removes all of the term IDs from the cache.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb                           WordPress database abstraction object.
 * @global bool $_wp_suspend_cache_invalidation
 *
 * @param int|int[] $ids            Single or array of term IDs.
 * @param string    $taxonomy       Optional. Taxonomy slug. Can be empty, in which case the taxonomies of the passed
 *                                  term IDs will be used. Default empty.
 * @param bool      $clean_taxonomy Optional. Whether to clean taxonomy wide caches (true), or just individual
 *                                  term object caches (false). Default true.
 */
function clean_term_cache( $ids, $taxonomy = '', $clean_taxonomy = true ) {
	global $wpdb, $_wp_suspend_cache_invalidation;

	if ( ! empty( $_wp_suspend_cache_invalidation ) ) {
		return;
	}

	if ( ! is_array( $ids ) ) {
		$ids = array( $ids );
	}

	$taxonomies = array();
	// If no taxonomy, assume tt_ids.
	if ( empty( $taxonomy ) ) {
		$tt_ids = array_map( 'intval', $ids );
		$tt_ids = implode( ', ', $tt_ids );
		$terms  = $wpdb->get_results( "SELECT term_id, taxonomy FROM $wpdb->term_taxonomy WHERE term_taxonomy_id IN ($tt_ids)" );
		$ids    = array();

		foreach ( (array) $terms as $term ) {
			$taxonomies[] = $term->taxonomy;
			$ids[]        = $term->term_id;
		}
		wp_cache_delete_multiple( $ids, 'terms' );
		$taxonomies = array_unique( $taxonomies );
	} else {
		wp_cache_delete_multiple( $ids, 'terms' );
		$taxonomies = array( $taxonomy );
	}

	foreach ( $taxonomies as $taxonomy ) {
		if ( $clean_taxonomy ) {
			clean_taxonomy_cache( $taxonomy );
		}

		/**
		 * Fires once after each taxonomy's term cache has been cleaned.
		 *
		 * @since 2.5.0
		 * @since 4.5.0 Added the `$clean_taxonomy` parameter.
		 *
		 * @param array  $ids            An array of term IDs.
		 * @param string $taxonomy       Taxonomy slug.
		 * @param bool   $clean_taxonomy Whether or not to clean taxonomy-wide caches
		 */
		do_action( 'clean_term_cache', $ids, $taxonomy, $clean_taxonomy );
	}

	wp_cache_set_terms_last_changed();
}

/**
 * Cleans the caches for a taxonomy.
 *
 * @since 4.9.0
 *
 * @param string $taxonomy Taxonomy slug.
 */
function clean_taxonomy_cache( $taxonomy ) {
	wp_cache_delete( 'all_ids', $taxonomy );
	wp_cache_delete( 'get', $taxonomy );
	wp_cache_set_terms_last_changed();

	// Regenerate cached hierarchy.
	delete_option( "{$taxonomy}_children" );
	_get_term_hierarchy( $taxonomy );

	/**
	 * Fires after a taxonomy's caches have been cleaned.
	 *
	 * @since 4.9.0
	 *
	 * @param string $taxonomy Taxonomy slug.
	 */
	do_action( 'clean_taxonomy_cache', $taxonomy );
}

/**
 * Retrieves the cached term objects for the given object ID.
 *
 * Upstream functions (like get_the_terms() and is_object_in_term()) are
 * responsible for populating the object-term relationship cache. The current
 * function only fetches relationship data that is already in the cache.
 *
 * @since 2.3.0
 * @since 4.7.0 Returns a `WP_Error` object if there's an error with
 *              any of the matched terms.
 *
 * @param int    $id       Term object ID, for example a post, comment, or user ID.
 * @param string $taxonomy Taxonomy name.
 * @return bool|WP_Term[]|WP_Error Array of `WP_Term` objects, if cached.
 *                                 False if cache is empty for `$taxonomy` and `$id`.
 *                                 WP_Error if get_term() returns an error object for any term.
 */
function get_object_term_cache( $id, $taxonomy ) {
	$_term_ids = wp_cache_get( $id, "{$taxonomy}_relationships" );

	// We leave the priming of relationship caches to upstream functions.
	if ( false === $_term_ids ) {
		return false;
	}

	// Backward compatibility for if a plugin is putting objects into the cache, rather than IDs.
	$term_ids = array();
	foreach ( $_term_ids as $term_id ) {
		if ( is_numeric( $term_id ) ) {
			$term_ids[] = (int) $term_id;
		} elseif ( isset( $term_id->term_id ) ) {
			$term_ids[] = (int) $term_id->term_id;
		}
	}

	// Fill the term objects.
	_prime_term_caches( $term_ids );

	$terms = array();
	foreach ( $term_ids as $term_id ) {
		$term = get_term( $term_id, $taxonomy );
		if ( is_wp_error( $term ) ) {
			return $term;
		}

		$terms[] = $term;
	}

	return $terms;
}

/**
 * Updates the cache for the given term object ID(s).
 *
 * Note: Due to performance concerns, great care should be taken to only update
 * term caches when necessary. Processing time can increase exponentially depending
 * on both the number of passed term IDs and the number of taxonomies those terms
 * belong to.
 *
 * Caches will only be updated for terms not already cached.
 *
 * @since 2.3.0
 *
 * @param string|int[]    $object_ids  Comma-separated list or array of term object IDs.
 * @param string|string[] $object_type The taxonomy object type or array of the same.
 * @return void|false Void on success or if the `$object_ids` parameter is empty,
 *                    false if all of the terms in `$object_ids` are already cached.
 */
function update_object_term_cache( $object_ids, $object_type ) {
	if ( empty( $object_ids ) ) {
		return;
	}

	if ( ! is_array( $object_ids ) ) {
		$object_ids = explode( ',', $object_ids );
	}

	$object_ids     = array_map( 'intval', $object_ids );
	$non_cached_ids = array();

	$taxonomies = get_object_taxonomies( $object_type );

	foreach ( $taxonomies as $taxonomy ) {
		$cache_values = wp_cache_get_multiple( (array) $object_ids, "{$taxonomy}_relationships" );

		foreach ( $cache_values as $id => $value ) {
			if ( false === $value ) {
				$non_cached_ids[] = $id;
			}
		}
	}

	if ( empty( $non_cached_ids ) ) {
		return false;
	}

	$non_cached_ids = array_unique( $non_cached_ids );

	$terms = wp_get_object_terms(
		$non_cached_ids,
		$taxonomies,
		array(
			'fields'                 => 'all_with_object_id',
			'orderby'                => 'name',
			'update_term_meta_cache' => false,
		)
	);

	$object_terms = array();
	foreach ( (array) $terms as $term ) {
		$object_terms[ $term->object_id ][ $term->taxonomy ][] = $term->term_id;
	}

	foreach ( $non_cached_ids as $id ) {
		foreach ( $taxonomies as $taxonomy ) {
			if ( ! isset( $object_terms[ $id ][ $taxonomy ] ) ) {
				if ( ! isset( $object_terms[ $id ] ) ) {
					$object_terms[ $id ] = array();
				}
				$object_terms[ $id ][ $taxonomy ] = array();
			}
		}
	}

	$cache_values = array();
	foreach ( $object_terms as $id => $value ) {
		foreach ( $value as $taxonomy => $terms ) {
			$cache_values[ $taxonomy ][ $id ] = $terms;
		}
	}
	foreach ( $cache_values as $taxonomy => $data ) {
		wp_cache_add_multiple( $data, "{$taxonomy}_relationships" );
	}
}

/**
 * Updates terms in cache.
 *
 * @since 2.3.0
 *
 * @param WP_Term[] $terms    Array of term objects to change.
 * @param string    $taxonomy Not used.
 */
function update_term_cache( $terms, $taxonomy = '' ) {
	$data = array();
	foreach ( (array) $terms as $term ) {
		// Create a copy in case the array was passed by reference.
		$_term = clone $term;

		// Object ID should not be cached.
		unset( $_term->object_id );

		$data[ $term->term_id ] = $_term;
	}
	wp_cache_add_multiple( $data, 'terms' );
}

//
// Private.
//

/**
 * Retrieves children of taxonomy as term IDs.
 *
 * @access private
 * @since 2.3.0
 *
 * @param string $taxonomy Taxonomy name.
 * @return array Empty if $taxonomy isn't hierarchical or returns children as term IDs.
 */
function _get_term_hierarchy( $taxonomy ) {
	if ( ! is_taxonomy_hierarchical( $taxonomy ) ) {
		return array();
	}
	$children = get_option( "{$taxonomy}_children" );

	if ( is_array( $children ) ) {
		return $children;
	}
	$children = array();
	$terms    = get_terms(
		array(
			'taxonomy'               => $taxonomy,
			'get'                    => 'all',
			'orderby'                => 'id',
			'fields'                 => 'id=>parent',
			'update_term_meta_cache' => false,
		)
	);
	foreach ( $terms as $term_id => $parent ) {
		if ( $parent > 0 ) {
			$children[ $parent ][] = $term_id;
		}
	}
	update_option( "{$taxonomy}_children", $children );

	return $children;
}

/**
 * Gets the subset of $terms that are descendants of $term_id.
 *
 * If `$terms` is an array of objects, then _get_term_children() returns an array of objects.
 * If `$terms` is an array of IDs, then _get_term_children() returns an array of IDs.
 *
 * @access private
 * @since 2.3.0
 *
 * @param int    $term_id   The ancestor term: all returned terms should be descendants of `$term_id`.
 * @param array  $terms     The set of terms - either an array of term objects or term IDs - from which those that
 *                          are descendants of $term_id will be chosen.
 * @param string $taxonomy  The taxonomy which determines the hierarchy of the terms.
 * @param array  $ancestors Optional. Term ancestors that have already been identified. Passed by reference, to keep
 *                          track of found terms when recursing the hierarchy. The array of located ancestors is used
 *                          to prevent infinite recursion loops. For performance, `term_ids` are used as array keys,
 *                          with 1 as value. Default empty array.
 * @return array|WP_Error The subset of $terms that are descendants of $term_id.
 */
function _get_term_children( $term_id, $terms, $taxonomy, &$ancestors = array() ) {
	$empty_array = array();
	if ( empty( $terms ) ) {
		return $empty_array;
	}

	$term_id      = (int) $term_id;
	$term_list    = array();
	$has_children = _get_term_hierarchy( $taxonomy );

	if ( $term_id && ! isset( $has_children[ $term_id ] ) ) {
		return $empty_array;
	}

	// Include the term itself in the ancestors array, so we can properly detect when a loop has occurred.
	if ( empty( $ancestors ) ) {
		$ancestors[ $term_id ] = 1;
	}

	foreach ( (array) $terms as $term ) {
		$use_id = false;
		if ( ! is_object( $term ) ) {
			$term = get_term( $term, $taxonomy );
			if ( is_wp_error( $term ) ) {
				return $term;
			}
			$use_id = true;
		}

		// Don't recurse if we've already identified the term as a child - this indicates a loop.
		if ( isset( $ancestors[ $term->term_id ] ) ) {
			continue;
		}

		if ( (int) $term->parent === $term_id ) {
			if ( $use_id ) {
				$term_list[] = $term->term_id;
			} else {
				$term_list[] = $term;
			}

			if ( ! isset( $has_children[ $term->term_id ] ) ) {
				continue;
			}

			$ancestors[ $term->term_id ] = 1;

			$children = _get_term_children( $term->term_id, $terms, $taxonomy, $ancestors );
			if ( $children ) {
				$term_list = array_merge( $term_list, $children );
			}
		}
	}

	return $term_list;
}

/**
 * Adds count of children to parent count.
 *
 * Recalculates term counts by including items from child terms. Assumes all
 * relevant children are already in the $terms argument.
 *
 * @access private
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param object[]|WP_Term[] $terms    List of term objects (passed by reference).
 * @param string             $taxonomy Term context.
 */
function _pad_term_counts( &$terms, $taxonomy ) {
	global $wpdb;

	// This function only works for hierarchical taxonomies like post categories.
	if ( ! is_taxonomy_hierarchical( $taxonomy ) ) {
		return;
	}

	$term_hier = _get_term_hierarchy( $taxonomy );

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

	$term_items  = array();
	$terms_by_id = array();
	$term_ids    = array();

	foreach ( (array) $terms as $key => $term ) {
		$terms_by_id[ $term->term_id ]       = & $terms[ $key ];
		$term_ids[ $term->term_taxonomy_id ] = $term->term_id;
	}

	// Get the object and term IDs and stick them in a lookup table.
	$tax_obj      = get_taxonomy( $taxonomy );
	$object_types = esc_sql( $tax_obj->object_type );
	$results      = $wpdb->get_results( "SELECT object_id, term_taxonomy_id FROM $wpdb->term_relationships INNER JOIN $wpdb->posts ON object_id = ID WHERE term_taxonomy_id IN (" . implode( ',', array_keys( $term_ids ) ) . ") AND post_type IN ('" . implode( "', '", $object_types ) . "') AND post_status = 'publish'" );

	foreach ( $results as $row ) {
		$id = $term_ids[ $row->term_taxonomy_id ];

		$term_items[ $id ][ $row->object_id ] = isset( $term_items[ $id ][ $row->object_id ] ) ? ++$term_items[ $id ][ $row->object_id ] : 1;
	}

	// Touch every ancestor's lookup row for each post in each term.
	foreach ( $term_ids as $term_id ) {
		$child     = $term_id;
		$ancestors = array();
		while ( ! empty( $terms_by_id[ $child ] ) && $parent = $terms_by_id[ $child ]->parent ) {
			$ancestors[] = $child;

			if ( ! empty( $term_items[ $term_id ] ) ) {
				foreach ( $term_items[ $term_id ] as $item_id => $touches ) {
					$term_items[ $parent ][ $item_id ] = isset( $term_items[ $parent ][ $item_id ] ) ? ++$term_items[ $parent ][ $item_id ] : 1;
				}
			}

			$child = $parent;

			if ( in_array( $parent, $ancestors, true ) ) {
				break;
			}
		}
	}

	// Transfer the touched cells.
	foreach ( (array) $term_items as $id => $items ) {
		if ( isset( $terms_by_id[ $id ] ) ) {
			$terms_by_id[ $id ]->count = count( $items );
		}
	}
}

/**
 * Adds any terms from the given IDs to the cache that do not already exist in cache.
 *
 * @since 4.6.0
 * @since 6.1.0 This function is no longer marked as "private".
 * @since 6.3.0 Use wp_lazyload_term_meta() for lazy-loading of term meta.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param array $term_ids          Array of term IDs.
 * @param bool  $update_meta_cache Optional. Whether to update the meta cache. Default true.
 */
function _prime_term_caches( $term_ids, $update_meta_cache = true ) {
	global $wpdb;

	$non_cached_ids = _get_non_cached_ids( $term_ids, 'terms' );
	if ( ! empty( $non_cached_ids ) ) {
		$fresh_terms = $wpdb->get_results( sprintf( "SELECT t.*, tt.* FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy AS tt ON t.term_id = tt.term_id WHERE t.term_id IN (%s)", implode( ',', array_map( 'intval', $non_cached_ids ) ) ) );

		update_term_cache( $fresh_terms );
	}

	if ( $update_meta_cache ) {
		wp_lazyload_term_meta( $term_ids );
	}
}

//
// Default callbacks.
//

/**
 * Updates term count based on object types of the current taxonomy.
 *
 * Private function for the default callback for post_tag and category
 * taxonomies.
 *
 * @access private
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int[]       $terms    List of term taxonomy IDs.
 * @param WP_Taxonomy $taxonomy Current taxonomy object of terms.
 */
function _update_post_term_count( $terms, $taxonomy ) {
	global $wpdb;

	$object_types = (array) $taxonomy->object_type;

	foreach ( $object_types as &$object_type ) {
		list( $object_type ) = explode( ':', $object_type );
	}

	$object_types = array_unique( $object_types );

	$check_attachments = array_search( 'attachment', $object_types, true );
	if ( false !== $check_attachments ) {
		unset( $object_types[ $check_attachments ] );
		$check_attachments = true;
	}

	if ( $object_types ) {
		$object_types = esc_sql( array_filter( $object_types, 'post_type_exists' ) );
	}

	$post_statuses = array( 'publish' );

	/**
	 * Filters the post statuses for updating the term count.
	 *
	 * @since 5.7.0
	 *
	 * @param string[]    $post_statuses List of post statuses to include in the count. Default is 'publish'.
	 * @param WP_Taxonomy $taxonomy      Current taxonomy object.
	 */
	$post_statuses = esc_sql( apply_filters( 'update_post_term_count_statuses', $post_statuses, $taxonomy ) );

	foreach ( (array) $terms as $term ) {
		$count = 0;

		// Attachments can be 'inherit' status, we need to base count off the parent's status if so.
		if ( $check_attachments ) {
			// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.QuotedDynamicPlaceholderGeneration
			$count += (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_relationships, $wpdb->posts p1 WHERE p1.ID = $wpdb->term_relationships.object_id AND ( post_status IN ('" . implode( "', '", $post_statuses ) . "') OR ( post_status = 'inherit' AND post_parent > 0 AND ( SELECT post_status FROM $wpdb->posts WHERE ID = p1.post_parent ) IN ('" . implode( "', '", $post_statuses ) . "') ) ) AND post_type = 'attachment' AND term_taxonomy_id = %d", $term ) );
		}

		if ( $object_types ) {
			// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.QuotedDynamicPlaceholderGeneration
			$count += (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_relationships, $wpdb->posts WHERE $wpdb->posts.ID = $wpdb->term_relationships.object_id AND post_status IN ('" . implode( "', '", $post_statuses ) . "') AND post_type IN ('" . implode( "', '", $object_types ) . "') AND term_taxonomy_id = %d", $term ) );
		}

		/** This action is documented in wp-includes/taxonomy.php */
		do_action( 'edit_term_taxonomy', $term, $taxonomy->name );
		$wpdb->update( $wpdb->term_taxonomy, compact( 'count' ), array( 'term_taxonomy_id' => $term ) );

		/** This action is documented in wp-includes/taxonomy.php */
		do_action( 'edited_term_taxonomy', $term, $taxonomy->name );
	}
}

/**
 * Updates term count based on number of objects.
 *
 * Default callback for the 'link_category' taxonomy.
 *
 * @since 3.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int[]       $terms    List of term taxonomy IDs.
 * @param WP_Taxonomy $taxonomy Current taxonomy object of terms.
 */
function _update_generic_term_count( $terms, $taxonomy ) {
	global $wpdb;

	foreach ( (array) $terms as $term ) {
		$count = $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_relationships WHERE term_taxonomy_id = %d", $term ) );

		/** This action is documented in wp-includes/taxonomy.php */
		do_action( 'edit_term_taxonomy', $term, $taxonomy->name );
		$wpdb->update( $wpdb->term_taxonomy, compact( 'count' ), array( 'term_taxonomy_id' => $term ) );

		/** This action is documented in wp-includes/taxonomy.php */
		do_action( 'edited_term_taxonomy', $term, $taxonomy->name );
	}
}

/**
 * Creates a new term for a term_taxonomy item that currently shares its term
 * with another term_taxonomy.
 *
 * @ignore
 * @since 4.2.0
 * @since 4.3.0 Introduced `$record` parameter. Also, `$term_id` and
 *              `$term_taxonomy_id` can now accept objects.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int|object $term_id          ID of the shared term, or the shared term object.
 * @param int|object $term_taxonomy_id ID of the term_taxonomy item to receive a new term, or the term_taxonomy object
 *                                     (corresponding to a row from the term_taxonomy table).
 * @param bool       $record           Whether to record data about the split term in the options table. The recording
 *                                     process has the potential to be resource-intensive, so during batch operations
 *                                     it can be beneficial to skip inline recording and do it just once, after the
 *                                     batch is processed. Only set this to `false` if you know what you are doing.
 *                                     Default: true.
 * @return int|WP_Error When the current term does not need to be split (or cannot be split on the current
 *                      database schema), `$term_id` is returned. When the term is successfully split, the
 *                      new term_id is returned. A WP_Error is returned for miscellaneous errors.
 */
function _split_shared_term( $term_id, $term_taxonomy_id, $record = true ) {
	global $wpdb;

	if ( is_object( $term_id ) ) {
		$shared_term = $term_id;
		$term_id     = (int) $shared_term->term_id;
	}

	if ( is_object( $term_taxonomy_id ) ) {
		$term_taxonomy    = $term_taxonomy_id;
		$term_taxonomy_id = (int) $term_taxonomy->term_taxonomy_id;
	}

	// If there are no shared term_taxonomy rows, there's nothing to do here.
	$shared_tt_count = (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_taxonomy tt WHERE tt.term_id = %d AND tt.term_taxonomy_id != %d", $term_id, $term_taxonomy_id ) );

	if ( ! $shared_tt_count ) {
		return $term_id;
	}

	/*
	 * Verify that the term_taxonomy_id passed to the function is actually associated with the term_id.
	 * If there's a mismatch, it may mean that the term is already split. Return the actual term_id from the db.
	 */
	$check_term_id = (int) $wpdb->get_var( $wpdb->prepare( "SELECT term_id FROM $wpdb->term_taxonomy WHERE term_taxonomy_id = %d", $term_taxonomy_id ) );
	if ( $check_term_id !== $term_id ) {
		return $check_term_id;
	}

	// Pull up data about the currently shared slug, which we'll use to populate the new one.
	if ( empty( $shared_term ) ) {
		$shared_term = $wpdb->get_row( $wpdb->prepare( "SELECT t.* FROM $wpdb->terms t WHERE t.term_id = %d", $term_id ) );
	}

	$new_term_data = array(
		'name'       => $shared_term->name,
		'slug'       => $shared_term->slug,
		'term_group' => $shared_term->term_group,
	);

	if ( false === $wpdb->insert( $wpdb->terms, $new_term_data ) ) {
		return new WP_Error( 'db_insert_error', __( 'Could not split shared term.' ), $wpdb->last_error );
	}

	$new_term_id = (int) $wpdb->insert_id;

	// Update the existing term_taxonomy to point to the newly created term.
	$wpdb->update(
		$wpdb->term_taxonomy,
		array( 'term_id' => $new_term_id ),
		array( 'term_taxonomy_id' => $term_taxonomy_id )
	);

	// Reassign child terms to the new parent.
	if ( empty( $term_taxonomy ) ) {
		$term_taxonomy = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->term_taxonomy WHERE term_taxonomy_id = %d", $term_taxonomy_id ) );
	}

	$children_tt_ids = $wpdb->get_col( $wpdb->prepare( "SELECT term_taxonomy_id FROM $wpdb->term_taxonomy WHERE parent = %d AND taxonomy = %s", $term_id, $term_taxonomy->taxonomy ) );
	if ( ! empty( $children_tt_ids ) ) {
		foreach ( $children_tt_ids as $child_tt_id ) {
			$wpdb->update(
				$wpdb->term_taxonomy,
				array( 'parent' => $new_term_id ),
				array( 'term_taxonomy_id' => $child_tt_id )
			);
			clean_term_cache( (int) $child_tt_id, '', false );
		}
	} else {
		// If the term has no children, we must force its taxonomy cache to be rebuilt separately.
		clean_term_cache( $new_term_id, $term_taxonomy->taxonomy, false );
	}

	clean_term_cache( $term_id, $term_taxonomy->taxonomy, false );

	/*
	 * Taxonomy cache clearing is delayed to avoid race conditions that may occur when
	 * regenerating the taxonomy's hierarchy tree.
	 */
	$taxonomies_to_clean = array( $term_taxonomy->taxonomy );

	// Clean the cache for term taxonomies formerly shared with the current term.
	$shared_term_taxonomies = $wpdb->get_col( $wpdb->prepare( "SELECT taxonomy FROM $wpdb->term_taxonomy WHERE term_id = %d", $term_id ) );
	$taxonomies_to_clean    = array_merge( $taxonomies_to_clean, $shared_term_taxonomies );

	foreach ( $taxonomies_to_clean as $taxonomy_to_clean ) {
		clean_taxonomy_cache( $taxonomy_to_clean );
	}

	// Keep a record of term_ids that have been split, keyed by old term_id. See wp_get_split_term().
	if ( $record ) {
		$split_term_data = get_option( '_split_terms', array() );
		if ( ! isset( $split_term_data[ $term_id ] ) ) {
			$split_term_data[ $term_id ] = array();
		}

		$split_term_data[ $term_id ][ $term_taxonomy->taxonomy ] = $new_term_id;
		update_option( '_split_terms', $split_term_data );
	}

	// If we've just split the final shared term, set the "finished" flag.
	$shared_terms_exist = $wpdb->get_results(
		"SELECT tt.term_id, t.*, count(*) as term_tt_count FROM {$wpdb->term_taxonomy} tt
		 LEFT JOIN {$wpdb->terms} t ON t.term_id = tt.term_id
		 GROUP BY t.term_id
		 HAVING term_tt_count > 1
		 LIMIT 1"
	);
	if ( ! $shared_terms_exist ) {
		update_option( 'finished_splitting_shared_terms', true );
	}

	/**
	 * Fires after a previously shared taxonomy term is split into two separate terms.
	 *
	 * @since 4.2.0
	 *
	 * @param int    $term_id          ID of the formerly shared term.
	 * @param int    $new_term_id      ID of the new term created for the $term_taxonomy_id.
	 * @param int    $term_taxonomy_id ID for the term_taxonomy row affected by the split.
	 * @param string $taxonomy         Taxonomy for the split term.
	 */
	do_action( 'split_shared_term', $term_id, $new_term_id, $term_taxonomy_id, $term_taxonomy->taxonomy );

	return $new_term_id;
}

/**
 * Splits a batch of shared taxonomy terms.
 *
 * @since 4.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 */
function _wp_batch_split_terms() {
	global $wpdb;

	$lock_name = 'term_split.lock';

	// Try to lock.
	$lock_result = $wpdb->query( $wpdb->prepare( "INSERT IGNORE INTO `$wpdb->options` ( `option_name`, `option_value`, `autoload` ) VALUES (%s, %s, 'no') /* LOCK */", $lock_name, time() ) );

	if ( ! $lock_result ) {
		$lock_result = get_option( $lock_name );

		// Bail if we were unable to create a lock, or if the existing lock is still valid.
		if ( ! $lock_result || ( $lock_result > ( time() - HOUR_IN_SECONDS ) ) ) {
			wp_schedule_single_event( time() + ( 5 * MINUTE_IN_SECONDS ), 'wp_split_shared_term_batch' );
			return;
		}
	}

	// Update the lock, as by this point we've definitely got a lock, just need to fire the actions.
	update_option( $lock_name, time() );

	// Get a list of shared terms (those with more than one associated row in term_taxonomy).
	$shared_terms = $wpdb->get_results(
		"SELECT tt.term_id, t.*, count(*) as term_tt_count FROM {$wpdb->term_taxonomy} tt
		 LEFT JOIN {$wpdb->terms} t ON t.term_id = tt.term_id
		 GROUP BY t.term_id
		 HAVING term_tt_count > 1
		 LIMIT 10"
	);

	// No more terms, we're done here.
	if ( ! $shared_terms ) {
		update_option( 'finished_splitting_shared_terms', true );
		delete_option( $lock_name );
		return;
	}

	// Shared terms found? We'll need to run this script again.
	wp_schedule_single_event( time() + ( 2 * MINUTE_IN_SECONDS ), 'wp_split_shared_term_batch' );

	// Rekey shared term array for faster lookups.
	$_shared_terms = array();
	foreach ( $shared_terms as $shared_term ) {
		$term_id                   = (int) $shared_term->term_id;
		$_shared_terms[ $term_id ] = $shared_term;
	}
	$shared_terms = $_shared_terms;

	// Get term taxonomy data for all shared terms.
	$shared_term_ids = implode( ',', array_keys( $shared_terms ) );
	$shared_tts      = $wpdb->get_results( "SELECT * FROM {$wpdb->term_taxonomy} WHERE `term_id` IN ({$shared_term_ids})" );

	// Split term data recording is slow, so we do it just once, outside the loop.
	$split_term_data    = get_option( '_split_terms', array() );
	$skipped_first_term = array();
	$taxonomies         = array();
	foreach ( $shared_tts as $shared_tt ) {
		$term_id = (int) $shared_tt->term_id;

		// Don't split the first tt belonging to a given term_id.
		if ( ! isset( $skipped_first_term[ $term_id ] ) ) {
			$skipped_first_term[ $term_id ] = 1;
			continue;
		}

		if ( ! isset( $split_term_data[ $term_id ] ) ) {
			$split_term_data[ $term_id ] = array();
		}

		// Keep track of taxonomies whose hierarchies need flushing.
		if ( ! isset( $taxonomies[ $shared_tt->taxonomy ] ) ) {
			$taxonomies[ $shared_tt->taxonomy ] = 1;
		}

		// Split the term.
		$split_term_data[ $term_id ][ $shared_tt->taxonomy ] = _split_shared_term( $shared_terms[ $term_id ], $shared_tt, false );
	}

	// Rebuild the cached hierarchy for each affected taxonomy.
	foreach ( array_keys( $taxonomies ) as $tax ) {
		delete_option( "{$tax}_children" );
		_get_term_hierarchy( $tax );
	}

	update_option( '_split_terms', $split_term_data );

	delete_option( $lock_name );
}

/**
 * In order to avoid the _wp_batch_split_terms() job being accidentally removed,
 * checks that it's still scheduled while we haven't finished splitting terms.
 *
 * @ignore
 * @since 4.3.0
 */
function _wp_check_for_scheduled_split_terms() {
	if ( ! get_option( 'finished_splitting_shared_terms' ) && ! wp_next_scheduled( 'wp_split_shared_term_batch' ) ) {
		wp_schedule_single_event( time() + MINUTE_IN_SECONDS, 'wp_split_shared_term_batch' );
	}
}

/**
 * Checks default categories when a term gets split to see if any of them need to be updated.
 *
 * @ignore
 * @since 4.2.0
 *
 * @param int    $term_id          ID of the formerly shared term.
 * @param int    $new_term_id      ID of the new term created for the $term_taxonomy_id.
 * @param int    $term_taxonomy_id ID for the term_taxonomy row affected by the split.
 * @param string $taxonomy         Taxonomy for the split term.
 */
function _wp_check_split_default_terms( $term_id, $new_term_id, $term_taxonomy_id, $taxonomy ) {
	if ( 'category' !== $taxonomy ) {
		return;
	}

	foreach ( array( 'default_category', 'default_link_category', 'default_email_category' ) as $option ) {
		if ( (int) get_option( $option, -1 ) === $term_id ) {
			update_option( $option, $new_term_id );
		}
	}
}

/**
 * Checks menu items when a term gets split to see if any of them need to be updated.
 *
 * @ignore
 * @since 4.2.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $term_id          ID of the formerly shared term.
 * @param int    $new_term_id      ID of the new term created for the $term_taxonomy_id.
 * @param int    $term_taxonomy_id ID for the term_taxonomy row affected by the split.
 * @param string $taxonomy         Taxonomy for the split term.
 */
function _wp_check_split_terms_in_menus( $term_id, $new_term_id, $term_taxonomy_id, $taxonomy ) {
	global $wpdb;
	$post_ids = $wpdb->get_col(
		$wpdb->prepare(
			"SELECT m1.post_id
		FROM {$wpdb->postmeta} AS m1
			INNER JOIN {$wpdb->postmeta} AS m2 ON ( m2.post_id = m1.post_id )
			INNER JOIN {$wpdb->postmeta} AS m3 ON ( m3.post_id = m1.post_id )
		WHERE ( m1.meta_key = '_menu_item_type' AND m1.meta_value = 'taxonomy' )
			AND ( m2.meta_key = '_menu_item_object' AND m2.meta_value = %s )
			AND ( m3.meta_key = '_menu_item_object_id' AND m3.meta_value = %d )",
			$taxonomy,
			$term_id
		)
	);

	if ( $post_ids ) {
		foreach ( $post_ids as $post_id ) {
			update_post_meta( $post_id, '_menu_item_object_id', $new_term_id, $term_id );
		}
	}
}

/**
 * If the term being split is a nav_menu, changes associations.
 *
 * @ignore
 * @since 4.3.0
 *
 * @param int    $term_id          ID of the formerly shared term.
 * @param int    $new_term_id      ID of the new term created for the $term_taxonomy_id.
 * @param int    $term_taxonomy_id ID for the term_taxonomy row affected by the split.
 * @param string $taxonomy         Taxonomy for the split term.
 */
function _wp_check_split_nav_menu_terms( $term_id, $new_term_id, $term_taxonomy_id, $taxonomy ) {
	if ( 'nav_menu' !== $taxonomy ) {
		return;
	}

	// Update menu locations.
	$locations = get_nav_menu_locations();
	foreach ( $locations as $location => $menu_id ) {
		if ( $term_id === $menu_id ) {
			$locations[ $location ] = $new_term_id;
		}
	}
	set_theme_mod( 'nav_menu_locations', $locations );
}

/**
 * Gets data about terms that previously shared a single term_id, but have since been split.
 *
 * @since 4.2.0
 *
 * @param int $old_term_id Term ID. This is the old, pre-split term ID.
 * @return array Array of new term IDs, keyed by taxonomy.
 */
function wp_get_split_terms( $old_term_id ) {
	$split_terms = get_option( '_split_terms', array() );

	$terms = array();
	if ( isset( $split_terms[ $old_term_id ] ) ) {
		$terms = $split_terms[ $old_term_id ];
	}

	return $terms;
}

/**
 * Gets the new term ID corresponding to a previously split term.
 *
 * @since 4.2.0
 *
 * @param int    $old_term_id Term ID. This is the old, pre-split term ID.
 * @param string $taxonomy    Taxonomy that the term belongs to.
 * @return int|false If a previously split term is found corresponding to the old term_id and taxonomy,
 *                   the new term_id will be returned. If no previously split term is found matching
 *                   the parameters, returns false.
 */
function wp_get_split_term( $old_term_id, $taxonomy ) {
	$split_terms = wp_get_split_terms( $old_term_id );

	$term_id = false;
	if ( isset( $split_terms[ $taxonomy ] ) ) {
		$term_id = (int) $split_terms[ $taxonomy ];
	}

	return $term_id;
}

/**
 * Determines whether a term is shared between multiple taxonomies.
 *
 * Shared taxonomy terms began to be split in 4.3, but failed cron tasks or
 * other delays in upgrade routines may cause shared terms to remain.
 *
 * @since 4.4.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int $term_id Term ID.
 * @return bool Returns false if a term is not shared between multiple taxonomies or
 *              if splitting shared taxonomy terms is finished.
 */
function wp_term_is_shared( $term_id ) {
	global $wpdb;

	if ( get_option( 'finished_splitting_shared_terms' ) ) {
		return false;
	}

	$tt_count = $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM $wpdb->term_taxonomy WHERE term_id = %d", $term_id ) );

	return $tt_count > 1;
}

/**
 * Generates a permalink for a taxonomy term archive.
 *
 * @since 2.5.0
 *
 * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
 *
 * @param WP_Term|int|string $term     The term object, ID, or slug whose link will be retrieved.
 * @param string             $taxonomy Optional. Taxonomy. Default empty.
 * @return string|WP_Error URL of the taxonomy term archive on success, WP_Error if term does not exist.
 */
function get_term_link( $term, $taxonomy = '' ) {
	global $wp_rewrite;

	if ( ! is_object( $term ) ) {
		if ( is_int( $term ) ) {
			$term = get_term( $term, $taxonomy );
		} else {
			$term = get_term_by( 'slug', $term, $taxonomy );
		}
	}

	if ( ! is_object( $term ) ) {
		$term = new WP_Error( 'invalid_term', __( 'Empty Term.' ) );
	}

	if ( is_wp_error( $term ) ) {
		return $term;
	}

	$taxonomy = $term->taxonomy;

	$termlink = $wp_rewrite->get_extra_permastruct( $taxonomy );

	/**
	 * Filters the permalink structure for a term before token replacement occurs.
	 *
	 * @since 4.9.0
	 *
	 * @param string  $termlink The permalink structure for the term's taxonomy.
	 * @param WP_Term $term     The term object.
	 */
	$termlink = apply_filters( 'pre_term_link', $termlink, $term );

	$slug = $term->slug;
	$t    = get_taxonomy( $taxonomy );

	if ( empty( $termlink ) ) {
		if ( 'category' === $taxonomy ) {
			$termlink = '?cat=' . $term->term_id;
		} elseif ( $t->query_var ) {
			$termlink = "?$t->query_var=$slug";
		} else {
			$termlink = "?taxonomy=$taxonomy&term=$slug";
		}
		$termlink = home_url( $termlink );
	} else {
		if ( ! empty( $t->rewrite['hierarchical'] ) ) {
			$hierarchical_slugs = array();
			$ancestors          = get_ancestors( $term->term_id, $taxonomy, 'taxonomy' );
			foreach ( (array) $ancestors as $ancestor ) {
				$ancestor_term        = get_term( $ancestor, $taxonomy );
				$hierarchical_slugs[] = $ancestor_term->slug;
			}
			$hierarchical_slugs   = array_reverse( $hierarchical_slugs );
			$hierarchical_slugs[] = $slug;
			$termlink             = str_replace( "%$taxonomy%", implode( '/', $hierarchical_slugs ), $termlink );
		} else {
			$termlink = str_replace( "%$taxonomy%", $slug, $termlink );
		}
		$termlink = home_url( user_trailingslashit( $termlink, 'category' ) );
	}

	// Back compat filters.
	if ( 'post_tag' === $taxonomy ) {

		/**
		 * Filters the tag link.
		 *
		 * @since 2.3.0
		 * @since 2.5.0 Deprecated in favor of {@see 'term_link'} filter.
		 * @since 5.4.1 Restored (un-deprecated).
		 *
		 * @param string $termlink Tag link URL.
		 * @param int    $term_id  Term ID.
		 */
		$termlink = apply_filters( 'tag_link', $termlink, $term->term_id );
	} elseif ( 'category' === $taxonomy ) {

		/**
		 * Filters the category link.
		 *
		 * @since 1.5.0
		 * @since 2.5.0 Deprecated in favor of {@see 'term_link'} filter.
		 * @since 5.4.1 Restored (un-deprecated).
		 *
		 * @param string $termlink Category link URL.
		 * @param int    $term_id  Term ID.
		 */
		$termlink = apply_filters( 'category_link', $termlink, $term->term_id );
	}

	/**
	 * Filters the term link.
	 *
	 * @since 2.5.0
	 *
	 * @param string  $termlink Term link URL.
	 * @param WP_Term $term     Term object.
	 * @param string  $taxonomy Taxonomy slug.
	 */
	return apply_filters( 'term_link', $termlink, $term, $taxonomy );
}

/**
 * Displays the taxonomies of a post with available options.
 *
 * This function can be used within the loop to display the taxonomies for a
 * post without specifying the Post ID. You can also use it outside the Loop to
 * display the taxonomies for a specific post.
 *
 * @since 2.5.0
 *
 * @param array $args {
 *     Arguments about which post to use and how to format the output. Shares all of the arguments
 *     supported by get_the_taxonomies(), in addition to the following.
 *
 *     @type int|WP_Post $post   Post ID or object to get taxonomies of. Default current post.
 *     @type string      $before Displays before the taxonomies. Default empty string.
 *     @type string      $sep    Separates each taxonomy. Default is a space.
 *     @type string      $after  Displays after the taxonomies. Default empty string.
 * }
 */
function the_taxonomies( $args = array() ) {
	$defaults = array(
		'post'   => 0,
		'before' => '',
		'sep'    => ' ',
		'after'  => '',
	);

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

	echo $parsed_args['before'] . implode( $parsed_args['sep'], get_the_taxonomies( $parsed_args['post'], $parsed_args ) ) . $parsed_args['after'];
}

/**
 * Retrieves all taxonomies associated with a post.
 *
 * This function can be used within the loop. It will also return an array of
 * the taxonomies with links to the taxonomy and name.
 *
 * @since 2.5.0
 *
 * @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global $post.
 * @param array       $args {
 *           Optional. Arguments about how to format the list of taxonomies. Default empty array.
 *
 *     @type string $template      Template for displaying a taxonomy label and list of terms.
 *                                 Default is "Label: Terms."
 *     @type string $term_template Template for displaying a single term in the list. Default is the term name
 *                                 linked to its archive.
 * }
 * @return string[] List of taxonomies.
 */
function get_the_taxonomies( $post = 0, $args = array() ) {
	$post = get_post( $post );

	$args = wp_parse_args(
		$args,
		array(
			/* translators: %s: Taxonomy label, %l: List of terms formatted as per $term_template. */
			'template'      => __( '%s: %l.' ),
			'term_template' => '<a href="%1$s">%2$s</a>',
		)
	);

	$taxonomies = array();

	if ( ! $post ) {
		return $taxonomies;
	}

	foreach ( get_object_taxonomies( $post ) as $taxonomy ) {
		$t = (array) get_taxonomy( $taxonomy );
		if ( empty( $t['label'] ) ) {
			$t['label'] = $taxonomy;
		}
		if ( empty( $t['args'] ) ) {
			$t['args'] = array();
		}
		if ( empty( $t['template'] ) ) {
			$t['template'] = $args['template'];
		}
		if ( empty( $t['term_template'] ) ) {
			$t['term_template'] = $args['term_template'];
		}

		$terms = get_object_term_cache( $post->ID, $taxonomy );
		if ( false === $terms ) {
			$terms = wp_get_object_terms( $post->ID, $taxonomy, $t['args'] );
		}
		$links = array();

		foreach ( $terms as $term ) {
			$links[] = wp_sprintf( $t['term_template'], esc_attr( get_term_link( $term ) ), $term->name );
		}
		if ( $links ) {
			$taxonomies[ $taxonomy ] = wp_sprintf( $t['template'], $t['label'], $links, $terms );
		}
	}
	return $taxonomies;
}

/**
 * Retrieves all taxonomy names for the given post.
 *
 * @since 2.5.0
 *
 * @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global $post.
 * @return string[] An array of all taxonomy names for the given post.
 */
function get_post_taxonomies( $post = 0 ) {
	$post = get_post( $post );

	return get_object_taxonomies( $post );
}

/**
 * Determines if the given object is associated with any of the given terms.
 *
 * The given terms are checked against the object's terms' term_ids, names and slugs.
 * Terms given as integers will only be checked against the object's terms' term_ids.
 * If no terms are given, determines if object is associated with any terms in the given taxonomy.
 *
 * @since 2.7.0
 *
 * @param int                       $object_id ID of the object (post ID, link ID, ...).
 * @param string                    $taxonomy  Single taxonomy name.
 * @param int|string|int[]|string[] $terms     Optional. Term ID, name, slug, or array of such
 *                                             to check against. Default null.
 * @return bool|WP_Error WP_Error on input error.
 */
function is_object_in_term( $object_id, $taxonomy, $terms = null ) {
	$object_id = (int) $object_id;
	if ( ! $object_id ) {
		return new WP_Error( 'invalid_object', __( 'Invalid object ID.' ) );
	}

	$object_terms = get_object_term_cache( $object_id, $taxonomy );
	if ( false === $object_terms ) {
		$object_terms = wp_get_object_terms( $object_id, $taxonomy, array( 'update_term_meta_cache' => false ) );
		if ( is_wp_error( $object_terms ) ) {
			return $object_terms;
		}

		wp_cache_set( $object_id, wp_list_pluck( $object_terms, 'term_id' ), "{$taxonomy}_relationships" );
	}

	if ( is_wp_error( $object_terms ) ) {
		return $object_terms;
	}
	if ( empty( $object_terms ) ) {
		return false;
	}
	if ( empty( $terms ) ) {
		return ( ! empty( $object_terms ) );
	}

	$terms = (array) $terms;

	$ints = array_filter( $terms, 'is_int' );
	if ( $ints ) {
		$strs = array_diff( $terms, $ints );
	} else {
		$strs =& $terms;
	}

	foreach ( $object_terms as $object_term ) {
		// If term is an int, check against term_ids only.
		if ( $ints && in_array( $object_term->term_id, $ints, true ) ) {
			return true;
		}

		if ( $strs ) {
			// Only check numeric strings against term_id, to avoid false matches due to type juggling.
			$numeric_strs = array_map( 'intval', array_filter( $strs, 'is_numeric' ) );
			if ( in_array( $object_term->term_id, $numeric_strs, true ) ) {
				return true;
			}

			if ( in_array( $object_term->name, $strs, true ) ) {
				return true;
			}
			if ( in_array( $object_term->slug, $strs, true ) ) {
				return true;
			}
		}
	}

	return false;
}

/**
 * Determines if the given object type is associated with the given taxonomy.
 *
 * @since 3.0.0
 *
 * @param string $object_type Object type string.
 * @param string $taxonomy    Single taxonomy name.
 * @return bool True if object is associated with the taxonomy, otherwise false.
 */
function is_object_in_taxonomy( $object_type, $taxonomy ) {
	$taxonomies = get_object_taxonomies( $object_type );
	if ( empty( $taxonomies ) ) {
		return false;
	}
	return in_array( $taxonomy, $taxonomies, true );
}

/**
 * Gets an array of ancestor IDs for a given object.
 *
 * @since 3.1.0
 * @since 4.1.0 Introduced the `$resource_type` argument.
 *
 * @param int    $object_id     Optional. The ID of the object. Default 0.
 * @param string $object_type   Optional. The type of object for which we'll be retrieving
 *                              ancestors. Accepts a post type or a taxonomy name. Default empty.
 * @param string $resource_type Optional. Type of resource $object_type is. Accepts 'post_type'
 *                              or 'taxonomy'. Default empty.
 * @return int[] An array of IDs of ancestors from lowest to highest in the hierarchy.
 */
function get_ancestors( $object_id = 0, $object_type = '', $resource_type = '' ) {
	$object_id = (int) $object_id;

	$ancestors = array();

	if ( empty( $object_id ) ) {

		/** This filter is documented in wp-includes/taxonomy.php */
		return apply_filters( 'get_ancestors', $ancestors, $object_id, $object_type, $resource_type );
	}

	if ( ! $resource_type ) {
		if ( is_taxonomy_hierarchical( $object_type ) ) {
			$resource_type = 'taxonomy';
		} elseif ( post_type_exists( $object_type ) ) {
			$resource_type = 'post_type';
		}
	}

	if ( 'taxonomy' === $resource_type ) {
		$term = get_term( $object_id, $object_type );
		while ( ! is_wp_error( $term ) && ! empty( $term->parent ) && ! in_array( $term->parent, $ancestors, true ) ) {
			$ancestors[] = (int) $term->parent;
			$term        = get_term( $term->parent, $object_type );
		}
	} elseif ( 'post_type' === $resource_type ) {
		$ancestors = get_post_ancestors( $object_id );
	}

	/**
	 * Filters a given object's ancestors.
	 *
	 * @since 3.1.0
	 * @since 4.1.1 Introduced the `$resource_type` parameter.
	 *
	 * @param int[]  $ancestors     An array of IDs of object ancestors.
	 * @param int    $object_id     Object ID.
	 * @param string $object_type   Type of object.
	 * @param string $resource_type Type of resource $object_type is.
	 */
	return apply_filters( 'get_ancestors', $ancestors, $object_id, $object_type, $resource_type );
}

/**
 * Returns the term's parent's term ID.
 *
 * @since 3.1.0
 *
 * @param int    $term_id  Term ID.
 * @param string $taxonomy Taxonomy name.
 * @return int|false Parent term ID on success, false on failure.
 */
function wp_get_term_taxonomy_parent_id( $term_id, $taxonomy ) {
	$term = get_term( $term_id, $taxonomy );
	if ( ! $term || is_wp_error( $term ) ) {
		return false;
	}
	return (int) $term->parent;
}

/**
 * Checks the given subset of the term hierarchy for hierarchy loops.
 * Prevents loops from forming and breaks those that it finds.
 *
 * Attached to the {@see 'wp_update_term_parent'} filter.
 *
 * @since 3.1.0
 *
 * @param int    $parent_term `term_id` of the parent for the term we're checking.
 * @param int    $term_id     The term we're checking.
 * @param string $taxonomy    The taxonomy of the term we're checking.
 * @return int The new parent for the term.
 */
function wp_check_term_hierarchy_for_loops( $parent_term, $term_id, $taxonomy ) {
	// Nothing fancy here - bail.
	if ( ! $parent_term ) {
		return 0;
	}

	// Can't be its own parent.
	if ( $parent_term === $term_id ) {
		return 0;
	}

	// Now look for larger loops.
	$loop = wp_find_hierarchy_loop( 'wp_get_term_taxonomy_parent_id', $term_id, $parent_term, array( $taxonomy ) );
	if ( ! $loop ) {
		return $parent_term; // No loop.
	}

	// Setting $parent_term to the given value causes a loop.
	if ( isset( $loop[ $term_id ] ) ) {
		return 0;
	}

	// There's a loop, but it doesn't contain $term_id. Break the loop.
	foreach ( array_keys( $loop ) as $loop_member ) {
		wp_update_term( $loop_member, $taxonomy, array( 'parent' => 0 ) );
	}

	return $parent_term;
}

/**
 * Determines whether a taxonomy is considered "viewable".
 *
 * @since 5.1.0
 *
 * @param string|WP_Taxonomy $taxonomy Taxonomy name or object.
 * @return bool Whether the taxonomy should be considered viewable.
 */
function is_taxonomy_viewable( $taxonomy ) {
	if ( is_scalar( $taxonomy ) ) {
		$taxonomy = get_taxonomy( $taxonomy );
		if ( ! $taxonomy ) {
			return false;
		}
	}

	return $taxonomy->publicly_queryable;
}

/**
 * Determines whether a term is publicly viewable.
 *
 * A term is considered publicly viewable if its taxonomy is viewable.
 *
 * @since 6.1.0
 *
 * @param int|WP_Term $term Term ID or term object.
 * @return bool Whether the term is publicly viewable.
 */
function is_term_publicly_viewable( $term ) {
	$term = get_term( $term );

	if ( ! $term ) {
		return false;
	}

	return is_taxonomy_viewable( $term->taxonomy );
}

/**
 * Sets the last changed time for the 'terms' cache group.
 *
 * @since 5.0.0
 */
function wp_cache_set_terms_last_changed() {
	wp_cache_set_last_changed( 'terms' );
}

/**
 * Aborts calls to term meta if it is not supported.
 *
 * @since 5.0.0
 *
 * @param mixed $check Skip-value for whether to proceed term meta function execution.
 * @return mixed Original value of $check, or false if term meta is not supported.
 */
function wp_check_term_meta_support_prefilter( $check ) {
	if ( get_option( 'db_version' ) < 34370 ) {
		return false;
	}

	return $check;
}