00:0000:0000';

		// Strip the port (and [] from IPv6 addresses), if they exist.
		if ( false !== $left_bracket && false !== $right_bracket ) {
			$ip_addr = substr( $ip_addr, $left_bracket + 1, $right_bracket - $left_bracket - 1 );
		} elseif ( false !== $left_bracket || false !== $right_bracket ) {
			// The IP has one bracket, but not both, so it's malformed.
			return '::';
		}

		// Strip the reachability scope.
		if ( false !== $percent ) {
			$ip_addr = substr( $ip_addr, 0, $percent );
		}

		// No invalid characters should be left.
		if ( preg_match( '/[^0-9a-f:]/i', $ip_addr ) ) {
			return '::';
		}

		// Partially anonymize the IP by reducing it to the corresponding network ID.
		if ( function_exists( 'inet_pton' ) && function_exists( 'inet_ntop' ) ) {
			$ip_addr = inet_ntop( inet_pton( $ip_addr ) & inet_pton( $netmask ) );
			if ( false === $ip_addr) {
				return '::';
			}
		} elseif ( ! $ipv6_fallback ) {
			return '::';
		}
	} elseif ( $is_ipv4 ) {
		// Strip any port and partially anonymize the IP.
		$last_octet_position = strrpos( $ip_addr, '.' );
		$ip_addr             = substr( $ip_addr, 0, $last_octet_position ) . '.0';
	} else {
		return '0.0.0.0';
	}

	// Restore the IPv6 prefix to compatibility mode addresses.
	return $ip_prefix . $ip_addr;
}

/**
 * Return uniform "anonymous" data by type.
 *
 * @since 4.9.6
 *
 * @param  string $type The type of data to be anonymized.
 * @param  string $data Optional The data to be anonymized.
 * @return string The anonymous data for the requested type.
 */
function wp_privacy_anonymize_data( $type, $data = '' ) {

	switch ( $type ) {
		case 'email':
			$anonymous = 'deleted@site.invalid';
			break;
		case 'url':
			$anonymous = 'https://site.invalid';
			break;
		case 'ip':
			$anonymous = wp_privacy_anonymize_ip( $data );
			break;
		case 'date':
			$anonymous = '0000-00-00 00:00:00';
			break;
		case 'text':
			/* translators: deleted text */
			$anonymous = __( '[deleted]' );
			break;
		case 'longtext':
			/* translators: deleted long text */
			$anonymous = __( 'This content was deleted by the author.' );
			break;
		default:
			$anonymous = '';
	}

	/**
	 * Filters the anonymous data for each type.
	 *
	 * @since 4.9.6
	 *
	 * @param string $anonymous Anonymized data.
	 * @param string $type      Type of the data.
	 * @param string $data      Original data.
	 */
	return apply_filters( 'wp_privacy_anonymize_data', $anonymous, $type, $data );
}

/**
 * Returns the directory used to store personal data export files.
 *
 * @since 4.9.6
 *
 * @see wp_privacy_exports_url
 *
 * @return string Exports directory.
 */
function wp_privacy_exports_dir() {
	$upload_dir  = wp_upload_dir();
	$exports_dir = trailingslashit( $upload_dir['basedir'] ) . 'wp-personal-data-exports/';

	/**
	 * Filters the directory used to store personal data export files.
	 *
	 * @since 4.9.6
	 *
	 * @param string $exports_dir Exports directory.
	 */
	return apply_filters( 'wp_privacy_exports_dir', $exports_dir );
}

/**
 * Returns the URL of the directory used to store personal data export files.
 *
 * @since 4.9.6
 *
 * @see wp_privacy_exports_dir
 *
 * @return string Exports directory URL.
 */
function wp_privacy_exports_url() {
	$upload_dir  = wp_upload_dir();
	$exports_url = trailingslashit( $upload_dir['baseurl'] ) . 'wp-personal-data-exports/';

	/**
	 * Filters the URL of the directory used to store personal data export files.
	 *
	 * @since 4.9.6
	 *
	 * @param string $exports_url Exports directory URL.
	 */
	return apply_filters( 'wp_privacy_exports_url', $exports_url );
}

/**
 * Schedule a `WP_Cron` job to delete expired export files.
 *
 * @since 4.9.6
 */
function wp_schedule_delete_old_privacy_export_files() {
	if ( wp_installing() ) {
		return;
	}

	if ( ! wp_next_scheduled( 'wp_privacy_delete_old_export_files' ) ) {
		wp_schedule_event( time(), 'hourly', 'wp_privacy_delete_old_export_files' );
	}
}

/**
 * Cleans up export files older than three days old.
 *
 * The export files are stored in `wp-content/uploads`, and are therefore publicly
 * accessible. A CSPRN is appended to the filename to mitigate the risk of an
 * unauthorized person downloading the file, but it is still possible. Deleting
 * the file after the data subject has had a chance to delete it adds an additional
 * layer of protection.
 *
 * @since 4.9.6
 */
function wp_privacy_delete_old_export_files() {
	require_once( ABSPATH . 'wp-admin/includes/file.php' );

	$exports_dir  = wp_privacy_exports_dir();
	$export_files = list_files( $exports_dir, 100, array( 'index.html' ) );

	/**
	 * Filters the lifetime, in seconds, of a personal data export file.
	 *
	 * By default, the lifetime is 3 days. Once the file reaches that age, it will automatically
	 * be deleted by a cron job.
	 *
	 * @since 4.9.6
	 *
	 * @param int $expiration The expiration age of the export, in seconds.
	 */
	$expiration = apply_filters( 'wp_privacy_export_expiration', 3 * DAY_IN_SECONDS );

	foreach ( (array) $export_files as $export_file ) {
		$file_age_in_seconds = time() - filemtime( $export_file );

		if ( $expiration < $file_age_in_seconds ) {
			unlink( $export_file );
		}
	}
}