// Doesn't seem to be a valid IP.
		return false;
	}

	/**
	 * Convert bytes to readable format.
	 *
	 * @since 4.0.0
	 *
	 * @param  integer $bytes The size of the file.
	 * @return array          The original and readable file size.
	 */
	public function convertFileSize( $bytes ) {
		if ( empty( $bytes ) ) {
			return [
				'original' => 0,
				'readable' => '0 B'
			];
		}
		$i = floor( log( $bytes ) / log( 1024 ) );
		$sizes = [ 'B', 'KB', 'MB', 'GB', 'TB' ];

		return [
			'original' => $bytes,
			'readable' => sprintf( '%.02F', $bytes / pow( 1024, $i ) ) * 1 . ' ' . $sizes[ $i ]
		];
	}

	/**
	 * Sanitizes a given option value before we store it in the DB.
	 *
	 * Used by the migration and importer classes.
	 *
	 * @since 4.0.0
	 *
	 * @param  mixed $value The value.
	 * @return mixed $value The sanitized value.
	 */
	public function sanitizeOption( $value ) {
		switch ( gettype( $value ) ) {
			case 'boolean':
				return (bool) $value;
			case 'string':
				$value = aioseo()->helpers->decodeHtmlEntities( $value );

				return aioseo()->helpers->encodeOutputHtml( wp_strip_all_tags( wp_check_invalid_utf8( trim( $value ) ) ) );
			case 'integer':
				return intval( $value );
			case 'double':
				return floatval( $value );
			case 'array':
				$sanitized = [];
				foreach ( (array) $value as $child ) {
					$sanitized[] = aioseo()->helpers->sanitizeOption( $child );
				}

				return $sanitized;
			default:
				return false;
		}
	}

	/**
	 * Checks if the given string is serialized, and if so, unserializes it.
	 * If the serialized string contains an object, we abort to prevent PHP object injection.
	 *
	 * @since 4.1.0.2
	 *
	 * @param  string        $string         The string.
	 * @param  array|boolean $allowedClasses The allowed classes for unserialize.
	 * @return string|array                  The string or unserialized data.
	 */
	public function maybeUnserialize( $string, $allowedClasses = false ) {
		if ( ! is_string( $string ) ) {
			return $string;
		}

		$string = trim( $string );
		if ( is_serialized( $string ) ) {
			return @unserialize( $string, [ 'allowed_classes' => $allowedClasses ] ); // phpcs:disable PHPCompatibility.FunctionUse.NewFunctionParameters.unserialize_optionsFound
		}

		return $string;
	}

	/**
	 * Returns a deep clone of the given object.
	 * The built-in PHP clone KW provides a shallow clone. This method returns a deep clone that also clones nested object properties.
	 * You can use this method to sever the reference to nested objects.
	 *
	 * @since 4.4.7
	 *
	 * @return object The cloned object.
	 */
	public function deepClone( $object ) {
		return unserialize( serialize( $object ) );
	}

	/**
	 * Sanitizes a given variable
	 *
	 * @since 4.5.6
	 *
	 * @param  mixed $variable             The variable.
	 * @param  bool  $preserveHtml         Whether or not to preserve HTML for ALL fields.
	 * @param  array $fieldsToPreserveHtml Specific fields to preserve HTML for.
	 * @param  string $fieldName           The name of the current field (when looping over a list).
	 * @return mixed                       The sanitized variable.
	 */
	public function sanitize( $variable, $preserveHtml = false, $fieldsToPreserveHtml = [], $fieldName = '' ) {
		$type = gettype( $variable );
		switch ( $type ) {
			case 'boolean':
				return (bool) $variable;
			case 'string':
				if ( $preserveHtml || in_array( $fieldName, $fieldsToPreserveHtml, true ) ) {
					return aioseo()->helpers->decodeHtmlEntities( sanitize_text_field( htmlspecialchars( $variable, ENT_NOQUOTES, 'UTF-8' ) ) );
				}

				return sanitize_text_field( $variable );
			case 'integer':
				return intval( $variable );
			case 'float':
			case 'double':
				return floatval( $variable );
			case 'array':
				$array = [];
				foreach ( (array) $variable as $k => $v ) {
					$array[ $k ] = $this->sanitize( $v, $preserveHtml, $fieldsToPreserveHtml, $k );
				}

				return $array;
			default:
				return false;
		}
	}

	/**
	 * Return the version number with a filter to enable users to hide the version.
	 *
	 * @since 4.3.7
	 *
	 * @return string The current version or empty if the filter is active. Using ?aioseo-dev will override the filter.
	 */
	public function getAioseoVersion() {
		$version = aioseo()->version;

		if ( ! $this->isDev() && apply_filters( 'aioseo_hide_version_number', false ) ) {
			$version = '';
		}

		return $version;
	}

	/**
	 * Retrieves the marketing site articles.
	 *
	 * @since 4.7.2
	 *
	 * @param  bool  $fetchImage Whether to fetch the article image.
	 * @return array             The articles or an empty array on failure.
	 */
	public function fetchAioseoArticles( $fetchImage = false ) {
		$items = aioseo()->core->networkCache->get( 'rss_feed' );
		if ( null !== $items ) {
			return $items;
		}

		$options  = [
			'timeout'   => 10,
			'sslverify' => false,
		];
		$response = wp_remote_get( 'https://aioseo.com/wp-json/wp/v2/posts?per_page=4', $options );
		$body     = wp_remote_retrieve_body( $response );
		if ( ! $body ) {
			return [];
		}

		$cached = [];
		$items  = json_decode( $body, true );
		foreach ( $items as $k => $item ) {
			$cached[ $k ] = [
				'url'     => $item['link'],
				'title'   => $item['title']['rendered'],
				'date'    => date( get_option( 'date_format' ), strtotime( $item['date'] ) ),
				'content' => wp_html_excerpt( $item['content']['rendered'], 128, '…' ),
			];

			if ( $fetchImage ) {
				$response = wp_remote_get( $item['_links']['wp:featuredmedia'][0]['href'] ?? '', $options );
				$body     = wp_remote_retrieve_body( $response );
				if ( ! $body ) {
					continue;
				}

				$image = json_decode( $body, true );

				$cached[ $k ]['image'] = [
					'url'   => $image['source_url'] ?? '',
					'alt'   => $image['alt_text'] ?? '',
					'sizes' => $image['media_details']['sizes'] ?? ''
				];
			}
		}

		aioseo()->core->networkCache->update( 'rss_feed', $cached, 24 * HOUR_IN_SECONDS );

		return $cached;
	}
}