apply_block_hooks_to_content_from_post_object()

apply_block_hooks_to_content_from_post_object( string $content, WP_Post|null $post = null, callable $callback = 'insert_hooked_blocks', array|null $ignored_hooked_blocks_at_root = null ): string

function apply_block_hooks_to_content_from_post_object(
	$content,
	$post = null,
	$callback = 'insert_hooked_blocks',
	&$ignored_hooked_blocks_at_root = null
) {
	// Default to the current post if no context is provided.
	if ( null === $post ) {
		$post = get_post();
	}

	if ( ! $post instanceof WP_Post ) {
		return apply_block_hooks_to_content( $content, $post, $callback );
	}

	/*
	 * If the content was created using the classic editor or using a single Classic block
	 * (`core/freeform`), it might not contain any block markup at all.
	 * However, we still might need to inject hooked blocks in the first child or last child
	 * positions of the parent block. To be able to apply the Block Hooks algorithm, we wrap
	 * the content in a `core/freeform` wrapper block.
	 */
	if ( ! has_blocks( $content ) ) {
		$original_content = $content;

		$content_wrapped_in_classic_block = get_comment_delimited_block_content(
			'core/freeform',
			array(),
			$content
		);

		$content = $content_wrapped_in_classic_block;
	}

	$attributes = array();

	// If context is a post object, `ignoredHookedBlocks` information is stored in its post meta.
	$ignored_hooked_blocks = get_post_meta( $post->ID, '_wp_ignored_hooked_blocks', true );
	if ( ! empty( $ignored_hooked_blocks ) ) {
		$ignored_hooked_blocks  = json_decode( $ignored_hooked_blocks, true );
		$attributes['metadata'] = array(
			'ignoredHookedBlocks' => $ignored_hooked_blocks,
		);
	}

	/*
	 * We need to wrap the content in a temporary wrapper block with that metadata
	 * so the Block Hooks algorithm can insert blocks that are hooked as first or last child
	 * of the wrapper block.
	 * To that end, we need to determine the wrapper block type based on the post type.
	 */
	if ( 'wp_navigation' === $post->post_type ) {
		$wrapper_block_type = 'core/navigation';
	} elseif ( 'wp_block' === $post->post_type ) {
		$wrapper_block_type = 'core/block';
	} else {
		$wrapper_block_type = 'core/post-content';
	}

	$content = get_comment_delimited_block_content(
		$wrapper_block_type,
		$attributes,
		$content
	);

	/*
	 * We need to avoid inserting any blocks hooked into the `before` and `after` positions
	 * of the temporary wrapper block that we create to wrap the content.
	 * See https://core.trac.wordpress.org/ticket/63287 for more details.
	 */
	$suppress_blocks_from_insertion_before_and_after_wrapper_block = static function ( $hooked_block_types, $relative_position, $anchor_block_type ) use ( $wrapper_block_type ) {
		if (
			$wrapper_block_type === $anchor_block_type &&
			in_array( $relative_position, array( 'before', 'after' ), true )
		) {
			return array();
		}
		return $hooked_block_types;
	};

	// Apply Block Hooks.
	add_filter( 'hooked_block_types', $suppress_blocks_from_insertion_before_and_after_wrapper_block, PHP_INT_MAX, 3 );
	$content = apply_block_hooks_to_content( $content, $post, $callback );
	remove_filter( 'hooked_block_types', $suppress_blocks_from_insertion_before_and_after_wrapper_block, PHP_INT_MAX );

	if ( null !== $ignored_hooked_blocks_at_root ) {
		// Check wrapper block's metadata for ignored hooked blocks at the root level, and populate the reference parameter if needed.
		$wrapper_block_markup = extract_serialized_parent_block( $content );
		$wrapper_block        = parse_blocks( $wrapper_block_markup )[0];

		if ( ! empty( $wrapper_block['attrs']['metadata']['ignoredHookedBlocks'] ) ) {
			$ignored_hooked_blocks_at_root = $wrapper_block['attrs']['metadata']['ignoredHookedBlocks'];
		}
	}

	// Finally, we need to remove the temporary wrapper block.
	$content = remove_serialized_parent_block( $content );

	// If we wrapped the content in a `core/freeform` block, we also need to remove that.
	if ( ! empty( $content_wrapped_in_classic_block ) ) {
		/*
		 * We cannot simply use remove_serialized_parent_block() here,
		 * as that function assumes that the block wrapper is at the top level.
		 * However, there might now be a hooked block inserted next to it
		 * (as first or last child of the parent).
		 */
		$content = str_replace( $content_wrapped_in_classic_block, $original_content, $content );
	}

	return $content;
}