* @since 5.9.0

 *

 * Renders the `core/gallery` block on the server.

 * @since 6.0.0

	// Adds a style tag for the --wp--style--unstable-gallery-gap var.

	// The Gallery block needs to recalculate Image block width based on

	// the current gap setting in order to maintain the number of flex columns

	// so a css var is added to allow this.

	$gap = $attributes['style']['spacing']['blockGap'] ?? null;

			// Make sure $value is a string to avoid PHP 8.1 deprecation error in preg_match() when the value is null.

			$value = is_string( $value ) ? $value : '';

			$value = $value && preg_match( '%[\\\(&=}]|/\*%', $value ) ? null : $value;

			// Get spacing CSS variable from preset value if provided.

			if ( is_string( $value ) && str_contains( $value, 'var:preset|spacing|' ) ) {

				$index_to_splice = strrpos( $value, '|' ) + 1;

				$slug            = _wp_to_kebab_case( substr( $value, $index_to_splice ) );

				$value           = "var(--wp--preset--spacing--$slug)";

			}

			$gap[ $key ] = $value;

		// Make sure $gap is a string to avoid PHP 8.1 deprecation error in preg_match() when the value is null.

		$gap = is_string( $gap ) ? $gap : '';

		// Get spacing CSS variable from preset value if provided.

		if ( is_string( $gap ) && str_contains( $gap, 'var:preset|spacing|' ) ) {

			$index_to_splice = strrpos( $gap, '|' ) + 1;

			$slug            = _wp_to_kebab_case( substr( $gap, $index_to_splice ) );

			$gap             = "var(--wp--preset--spacing--$slug)";

		}

	$unique_gallery_classname = wp_unique_id( 'wp-block-gallery-' );

	$processed_content        = new WP_HTML_Tag_Processor( $content );

	$processed_content->next_tag();

	$processed_content->add_class( $unique_gallery_classname );

	// The unstable gallery gap calculation requires a real value (such as `0px`) and not `0`.

	if ( '0' === $gap_column ) {

		$gap_column = '0px';

	}

	$gallery_styles = array(

		array(

			'selector'     => ".wp-block-gallery.{$unique_gallery_classname}",

			'declarations' => array(

				'--wp--style--unstable-gallery-gap' => $gap_column,

				'gap'                               => $gap_value,

			),

		),

	);

	wp_style_engine_get_stylesheet_from_css_rules(

		$gallery_styles,

		array(

			'context' => 'block-supports',

		)

	);

	// The WP_HTML_Tag_Processor class calls get_updated_html() internally

	// when the instance is treated as a string, but here we explicitly

	// convert it to a string.

	$updated_content = $processed_content->get_updated_html();

	/*

	 * Randomize the order of image blocks. Ideally we should shuffle

	 * the `$parsed_block['innerBlocks']` via the `render_block_data` hook.

	 * However, this hook doesn't apply inner block updates when blocks are

	 * nested.

	 * @todo In the future, if this hook supports updating innerBlocks in

	 * nested blocks, it should be refactored.

	 *

	 * @see: https://github.com/WordPress/gutenberg/pull/58733

	 */

	if ( empty( $attributes['randomOrder'] ) ) {

		return $updated_content;

	}

	// This pattern matches figure elements with the `wp-block-image` class to

	// avoid the gallery's wrapping `figure` element and extract images only.

	$pattern = '/<figure[^>]*\bwp-block-image\b[^>]*>.*?<\/figure>/';

	// Find all Image blocks.

	preg_match_all( $pattern, $updated_content, $matches );

	if ( ! $matches ) {

		return $updated_content;

	}

	$image_blocks = $matches[0];

	// Randomize the order of Image blocks.

	shuffle( $image_blocks );

	$i       = 0;

	$content = preg_replace_callback(

		$pattern,

		static function () use ( $image_blocks, &$i ) {

			$new_image_block = $image_blocks[ $i ];

			++$i;

			return $new_image_block;

		$updated_content

 *

 * @since 5.9.0