Auto-inserting blocks: Add block inspector panel

lib/experimental/auto-inserting-blocks.php

@@ -64,6 +64,31 @@ function gutenberg_auto_insert_block( $inserted_block, $relative_position, $anch
 	};
 }
 
+/**
+ * Add auto-insertion information to a block type's controller.
+ *
+ * @param array  $inserted_block_type The type of block to insert.
+ * @param string $position            The position relative to the anchor block.
+ *                                    Can be 'before', 'after', 'first_child', or 'last_child'.
+ * @param string $anchor_block_type   The auto-inserted block will be inserted next to instances of this block type.
+ * @return callable A filter for the `rest_prepare_block_type` hook that adds an `auto_insert` field to the network response.
+ */
+function gutenberg_add_auto_insert_field_to_block_type_controller( $inserted_block_type, $position, $anchor_block_type ) {
+	return function( $response, $block_type ) use ( $inserted_block_type, $position, $anchor_block_type ) {
+		if ( $block_type->name !== $inserted_block_type ) {
+			return $response;
+		}
+
+		$data = $response->get_data();
+		if ( ! isset( $data['auto_insert'] ) ) {
+			$data['auto_insert'] = array();
+		}
+		$data['auto_insert'][ $anchor_block_type ] = $position;
+		$response->set_data( $data );
+		return $response;
+	};
+}
+
 /**
  * Register blocks for auto-insertion, based on their block.json metadata.
  *
@@ -113,6 +138,37 @@ function gutenberg_register_auto_inserted_blocks( $settings, $metadata ) {
 		$settings['auto_insert'][ $anchor_block_name ] = $mapped_position;
 	}
 
+	// Copied from `get_block_editor_server_block_settings()`.
+	$fields_to_pick = array(
+		'api_version'      => 'apiVersion',
+		'title'            => 'title',
+		'description'      => 'description',
+		'icon'             => 'icon',
+		'attributes'       => 'attributes',
+		'provides_context' => 'providesContext',
+		'uses_context'     => 'usesContext',
+		'selectors'        => 'selectors',
+		'supports'         => 'supports',
+		'category'         => 'category',
+		'styles'           => 'styles',
+		'textdomain'       => 'textdomain',
+		'parent'           => 'parent',
+		'ancestor'         => 'ancestor',
+		'keywords'         => 'keywords',
+		'example'          => 'example',
+		'variations'       => 'variations',
+	);
+	// Add `auto_insert` to the list of fields to pick.
+	$fields_to_pick['auto_insert'] = 'autoInsert';
+
+	$exposed_settings = array_intersect_key( $settings, $fields_to_pick );
+
+	// TODO: Make work for blocks registered via direct call to gutenberg_register_auto_inserted_block().
+	wp_add_inline_script(
+		'wp-blocks',
+		'wp.blocks.unstable__bootstrapServerSideBlockDefinitions(' . wp_json_encode( array( $inserted_block_name => $exposed_settings ) ) . ');'
+	);
+
 	return $settings;
 }
 add_filter( 'block_type_metadata_settings', 'gutenberg_register_auto_inserted_blocks', 10, 2 );
@@ -135,16 +191,27 @@ function gutenberg_register_auto_inserted_blocks( $settings, $metadata ) {
  * @return void
  */
 function gutenberg_register_auto_inserted_block( $inserted_block, $position, $anchor_block ) {
-		$inserted_block = array(
+		$inserted_block_array = array(
 			'blockName'    => $inserted_block,
 			'attrs'        => array(),
 			'innerHTML'    => '',
 			'innerContent' => array(),
 			'innerBlocks'  => array(),
 		);
 
-		$inserter = gutenberg_auto_insert_block( $inserted_block, $position, $anchor_block );
+		$inserter = gutenberg_auto_insert_block( $inserted_block_array, $position, $anchor_block );
 		add_filter( 'gutenberg_serialize_block', $inserter, 10, 1 );
+
+		/*
+		 * The block-types REST API controller uses objects of the `WP_Block_Type` class, which are
+		 * in turn created upon block type registration. However, that class does not contain
+		 * an `auto_insert` property (and is not easily extensible), so we have to use a different
+		 * mechanism to communicate to the controller which blocks have been registered for
+		 * auto-insertion. We're doing so here (i.e. upon block registration), by adding a filter to
+		 * the controller's response.
+		 */
+		$controller_extender = gutenberg_add_auto_insert_field_to_block_type_controller( $inserted_block, $position, $anchor_block );
+		add_filter( 'rest_prepare_block_type', $controller_extender, 10, 2 );
 }
 
 /**
@@ -256,3 +323,22 @@ function gutenberg_serialize_block( $block ) {
 function gutenberg_serialize_blocks( $blocks ) {
 	return implode( '', array_map( 'gutenberg_serialize_block', $blocks ) );
 }
+
+/**
+ * Register the `auto_insert` field for the block-types REST API controller.
+ *
+ * @return void
+ */
+function gutenberg_register_auto_insert_rest_field() {
+	register_rest_field(
+		'block-type',
+		'auto_insert',
+		array(
+			'schema' => array(
+				'description' => __( 'Block types that are automatically inserted next to this block, and their positions relative to it.', 'default' ),
+				'type'        => 'object',
+			),
+		)
+	);
+}
+add_action( 'rest_api_init', 'gutenberg_register_auto_insert_rest_field' );

lib/experimental/editor-settings.php

@@ -30,6 +30,10 @@ function gutenberg_enable_experiments() {
 	if ( gutenberg_is_experiment_enabled( 'gutenberg-no-tinymce' ) ) {
 		wp_add_inline_script( 'wp-block-library', 'window.__experimentalDisableTinymce = true', 'before' );
 	}
+
+	if ( $gutenberg_experiments && array_key_exists( 'gutenberg-auto-inserting-blocks', $gutenberg_experiments ) ) {
+		wp_add_inline_script( 'wp-block-editor', 'window.__experimentalAutoInsertingBlocks = true', 'before' );
+	}
 }
 
 add_action( 'admin_init', 'gutenberg_enable_experiments' );

packages/block-editor/src/hooks/auto-inserting-blocks.js

@@ -0,0 +1,235 @@
+/**
+ * WordPress dependencies
+ */
+import { __ } from '@wordpress/i18n';
+import { addFilter } from '@wordpress/hooks';
+import { Fragment } from '@wordpress/element';
+import { PanelBody, ToggleControl } from '@wordpress/components';
+import { createHigherOrderComponent } from '@wordpress/compose';
+import { createBlock, store as blocksStore } from '@wordpress/blocks';
+import { useDispatch, useSelect } from '@wordpress/data';
+
+/**
+ * Internal dependencies
+ */
+import { InspectorControls } from '../components';
+import { store as blockEditorStore } from '../store';
+
+function AutoInsertingBlocksControl( props ) {
+	const { autoInsertedBlocksForCurrentBlock, groupedAutoInsertedBlocks } =
+		useSelect(
+			( select ) => {
+				const { getBlockTypes } = select( blocksStore );
+				const _autoInsertedBlocksForCurrentBlock =
+					getBlockTypes()?.filter(
+						( block ) =>
+							block.autoInsert &&
+							Object.keys( block.autoInsert ).includes(
+								props.blockName
+							)
+					);
+
+				// Group by block namespace (i.e. prefix before the slash).
+				const _groupedAutoInsertedBlocks =
+					_autoInsertedBlocksForCurrentBlock?.reduce(
+						( groups, block ) => {
+							const [ prefix ] = block.name.split( '/' );
+							if ( ! groups[ prefix ] ) {
+								groups[ prefix ] = [];
+							}
+							groups[ prefix ].push( block );
+							return groups;
+						},
+						{}
+					);
+
+				return {
+					autoInsertedBlocksForCurrentBlock:
+						_autoInsertedBlocksForCurrentBlock,
+					groupedAutoInsertedBlocks: _groupedAutoInsertedBlocks,
+				};
+			},
+			[ props.blockName ]
+		);
+
+	const {
+		autoInsertedBlockClientIds,
+		blockIndex,
+		rootClientId,
+		innerBlocksLength,
+	} = useSelect(
+		( select ) => {
+			const { getBlock, getBlockIndex, getBlockRootClientId } =
+				select( blockEditorStore );
+			const _rootClientId = getBlockRootClientId( props.clientId );
+
+			const _autoInsertedBlockClientIds =
+				autoInsertedBlocksForCurrentBlock.reduce(
+					( clientIds, block ) => {
+						const relativePosition =
+							block?.autoInsert?.[ props.blockName ];
+						let candidates;
+
+						switch ( relativePosition ) {
+							case 'before':
+							case 'after':
+								// Any of the current block's siblings (with the right block type) qualifies
+								// as an auto-inserted block (inserted `before` or `after` the current one),
+								// as the block might've been auto-inserted and then moved around a bit by the user.
+								candidates =
+									getBlock( _rootClientId )?.innerBlocks;
+								break;
+
+							case 'first_child':
+							case 'last_child':
+								// Any of the current block's child blocks (with the right block type) qualifies
+								// as an auto-inserted first or last child block, as the block might've been
+								// auto-inserted and then moved around a bit by the user.
+								candidates = getBlock(
+									props.clientId
+								).innerBlocks;
+								break;
+						}
+
+						const autoInsertedBlock = candidates?.find(
+							( { name } ) => name === block.name
+						);
+
+						if ( autoInsertedBlock ) {
+							clientIds[ block.name ] =
+								autoInsertedBlock.clientId;
+						}
+
+						// TOOD: If no auto-inserted block was found in any of its designated locations,
+						// we want to check if it's present elsewhere in the block tree.
+						// If it is, we'd consider it manually inserted and would want to remove the
+						// corresponding toggle from the block inspector panel.
+
+						return clientIds;
+					},
+					{}
+				);
+
+			return {
+				blockIndex: getBlockIndex( props.clientId ),
+				innerBlocksLength: getBlock( props.clientId )?.innerBlocks
+					?.length,
+				rootClientId: _rootClientId,
+				autoInsertedBlockClientIds: _autoInsertedBlockClientIds,
+			};
+		},
+		[ autoInsertedBlocksForCurrentBlock, props.blockName, props.clientId ]
+	);
+
+	const { insertBlock, removeBlock } = useDispatch( blockEditorStore );
+
+	if ( ! autoInsertedBlocksForCurrentBlock.length ) {
+		return null;
+	}
+
+	const insertBlockIntoDesignatedLocation = ( block, relativePosition ) => {
+		switch ( relativePosition ) {
+			case 'before':
+			case 'after':
+				insertBlock(
+					block,
+					relativePosition === 'after' ? blockIndex + 1 : blockIndex,
+					rootClientId, // Insert as a child of the current block's parent
+					false
+				);
+				break;
+
+			case 'first_child':
+			case 'last_child':
+				insertBlock(
+					block,
+					// TODO: It'd be great if insertBlock() would accept negative indices for insertion.
+					relativePosition === 'first_child' ? 0 : innerBlocksLength,
+					props.clientId, // Insert as a child of the current block.
+					false
+				);
+				break;
+		}
+	};
+
+	return (
+		<InspectorControls>
+			<PanelBody title={ __( 'Plugins' ) } initialOpen={ true }>
+				{ Object.keys( groupedAutoInsertedBlocks ).map( ( vendor ) => {
+					return (
+						<Fragment key={ vendor }>
+							<h3>{ vendor }</h3>
+							{ groupedAutoInsertedBlocks[ vendor ].map(
+								( block ) => {
+									// TODO: Display block icon.
+									// <BlockIcon icon={ block.icon } />
+
+									const checked =
+										block.name in
+										autoInsertedBlockClientIds;
+
+									return (
+										<ToggleControl
+											checked={ checked }
+											key={ block.title }
+											label={ block.title }
+											onChange={ () => {
+												if ( ! checked ) {
+													// Create and insert block.
+													const relativePosition =
+														block.autoInsert[
+															props.blockName
+														];
+													insertBlockIntoDesignatedLocation(
+														createBlock(
+															block.name
+														),
+														relativePosition
+													);
+													return;
+												}
+
+												// Remove block.
+												const clientId =
+													autoInsertedBlockClientIds[
+														block.name
+													];
+												removeBlock( clientId, false );
+											} }
+										/>
+									);
+								}
+							) }
+						</Fragment>
+					);
+				} ) }
+			</PanelBody>
+		</InspectorControls>
+	);
+}
+
+export const withAutoInsertingBlocks = createHigherOrderComponent(
+	( BlockEdit ) => {
+		return ( props ) => {
+			const blockEdit = <BlockEdit key="edit" { ...props } />;
+			return (
+				<>
+					{ blockEdit }
+					<AutoInsertingBlocksControl
+						blockName={ props.name }
+						clientId={ props.clientId }
+					/>
+				</>
+			);
+		};
+	},
+	'withAutoInsertingBlocks'
+);
+
+if ( window?.__experimentalAutoInsertingBlocks ) {
+	addFilter(
+		'editor.BlockEdit',
+		'core/auto-inserting-blocks/with-inspector-control',
+		withAutoInsertingBlocks
+	);
+}

packages/block-editor/src/hooks/index.js

@@ -22,6 +22,7 @@ import './metadata';
 import './metadata-name';
 import './behaviors';
 import './custom-fields';
+import './auto-inserting-blocks';
 
 export { useCustomSides } from './dimensions';
 export { useLayoutClasses, useLayoutStyles } from './layout';