@wordpress/block-library/src/template-part/edit/utils/transformers.js

Block library for the WordPress editor.

/**
 * WordPress dependencies
 */
import {
	parse,
	cloneBlock,
	createBlock,
	getGroupingBlockName,
	getPossibleBlockTransformations,
	switchToBlockType,
} from '@wordpress/blocks';

/**
 * Converts a widget entity record into a block.
 *
 * @param {Object} widget The widget entity record.
 * @return {Object} a block (converted from the entity record).
 */
export function transformWidgetToBlock( widget ) {
	if ( widget.id_base !== 'block' ) {
		let attributes;
		if ( widget._embedded.about[ 0 ].is_multi ) {
			attributes = {
				idBase: widget.id_base,
				instance: widget.instance,
			};
		} else {
			attributes = {
				id: widget.id,
			};
		}

		return switchLegacyWidgetType(
			createBlock( 'core/legacy-widget', attributes )
		);
	}

	const parsedBlocks = parse( widget.instance.raw.content, {
		__unstableSkipAutop: true,
	} );

	if ( ! parsedBlocks.length ) {
		return undefined;
	}

	const block = parsedBlocks[ 0 ];

	if ( block.name === 'core/widget-group' ) {
		return createBlock(
			getGroupingBlockName(),
			undefined,
			transformInnerBlocks( block.innerBlocks )
		);
	}

	if ( block.innerBlocks.length > 0 ) {
		return cloneBlock(
			block,
			undefined,
			transformInnerBlocks( block.innerBlocks )
		);
	}

	return block;
}

/**
 * Switch Legacy Widget to the first matching transformation block.
 *
 * @param {Object} block Legacy Widget block object
 * @return {Object|undefined} a block
 */
function switchLegacyWidgetType( block ) {
	const transforms = getPossibleBlockTransformations( [ block ] ).filter(
		( item ) => {
			// The block without any transformations can't be a wildcard.
			if ( ! item.transforms ) {
				return true;
			}

			const hasWildCardFrom = item.transforms?.from?.find(
				( from ) => from.blocks && from.blocks.includes( '*' )
			);
			const hasWildCardTo = item.transforms?.to?.find(
				( to ) => to.blocks && to.blocks.includes( '*' )
			);

			// Skip wildcard transformations.
			return ! hasWildCardFrom && ! hasWildCardTo;
		}
	);

	if ( ! transforms.length ) {
		return undefined;
	}

	return switchToBlockType( block, transforms[ 0 ].name );
}

function transformInnerBlocks( innerBlocks = [] ) {
	return innerBlocks
		.flatMap( ( block ) => {
			if ( block.name === 'core/legacy-widget' ) {
				return switchLegacyWidgetType( block );
			}

			return createBlock(
				block.name,
				block.attributes,
				transformInnerBlocks( block.innerBlocks )
			);
		} )
		.filter( ( block ) => !! block );
}