Template Parts: Add an option to import widgets from the sidebars (#4…

…5509)

* Template Part: Introduce an option to import widgets
* Only display active sidebars with widgets as options
* Use the sidebar name as the new template part title
* Support legacy widgets
* Prefix imported template parts to avoid name collision
* Add missing docblock
* Update labels
* Move settings into the advanced inspector controls panel
* Update API response for sidebars and mark them as 'inactive'
* A minor design adjustments
* Fix the rendering order bug
* Transform legacy widgets before importing
* Avoid hardcoding names of the blocks with wildcard transformations
* Skip 'wp_inactive_widgets' widget area
* Use 'HStack'
* Allow overriding Legacy Widget block settings during registration
* Override only supports settings
* Improve spacing
* Add the legacy widget to the post editor

Co-authored-by: Robert Anderson <robert@noisysocks.com>

lib/compat/wordpress-6.2/rest-api.php

@@ -101,3 +101,18 @@ function gutenberg_register_global_styles_endpoints() {
 	$editor_settings->register_routes();
 }
 add_action( 'rest_api_init', 'gutenberg_register_global_styles_endpoints' );
+
+/**
+ * Updates REST API response for the sidebars and marks them as 'inactive'.
+ *
+ * Note: This can be a part of the `prepare_item_for_response` in `class-wp-rest-sidebars-controller.php`.
+ *
+ * @param WP_REST_Response $response The sidebar response object.
+ * @return WP_REST_Response $response Updated response object.
+ */
+function gutenberg_modify_rest_sidebars_response( $response ) {
+	$response->data['status'] = wp_is_block_theme() ? 'inactive' : 'active';
+
+	return $response;
+}
+add_filter( 'rest_prepare_sidebar', 'gutenberg_modify_rest_sidebars_response' );

lib/compat/wordpress-6.2/theme.php

@@ -0,0 +1,23 @@
+<?php
+/**
+ * Theme overrides for WP 6.2.
+ *
+ * @package gutenberg
+ */
+
+/**
+ * Store legacy sidebars for later use by block themes.
+ *
+ * Note: This can be a part of the `switch_theme` method in `wp-includes/theme.php`.
+ *
+ * @param string   $new_name  Name of the new theme.
+ * @param WP_Theme $new_theme WP_Theme instance of the new theme.
+ */
+function gutenberg_set_legacy_sidebars( $new_name, $new_theme ) {
+	global $wp_registered_sidebars;
+
+	if ( $new_theme->is_block_theme() ) {
+		set_theme_mod( 'wp_legacy_sidebars', $wp_registered_sidebars );
+	}
+}
+add_action( 'switch_theme', 'gutenberg_set_legacy_sidebars', 10, 2 );

lib/compat/wordpress-6.2/widgets.php

@@ -0,0 +1,32 @@
+<?php
+/**
+ * Core Widget APIs for WP 6.2.
+ *
+ * @package gutenberg
+ */
+
+if ( ! function_exists( '_wp_block_theme_stub_sidebars' ) ) {
+	/**
+	 * Register the previous theme's sidebars for the block themes.
+	 *
+	 * @return void
+	 */
+	function _wp_block_theme_stub_sidebars() {
+		global $wp_registered_sidebars;
+
+		if ( ! wp_is_block_theme() ) {
+			return;
+		}
+
+		$legacy_sidebars = get_theme_mod( 'wp_legacy_sidebars' );
+		if ( empty( $legacy_sidebars ) ) {
+			return;
+		}
+
+		// Don't use `register_sidebar` since it will enable the `widgets` support for a theme.
+		foreach ( $legacy_sidebars as $sidebar ) {
+			$wp_registered_sidebars[ $sidebar['id'] ] = $sidebar;
+		}
+	}
+	add_action( 'widgets_init', '_wp_block_theme_stub_sidebars' );
+}

lib/load.php

@@ -85,6 +85,8 @@ function gutenberg_is_experiment_enabled( $name ) {
 require __DIR__ . '/compat/wordpress-6.2/edit-form-blocks.php';
 require __DIR__ . '/compat/wordpress-6.2/site-editor.php';
 require __DIR__ . '/compat/wordpress-6.2/block-editor-settings.php';
+require __DIR__ . '/compat/wordpress-6.2/theme.php';
+require __DIR__ . '/compat/wordpress-6.2/widgets.php';
 
 // Experimental features.
 remove_action( 'plugins_loaded', '_wp_theme_json_webfonts_handler' ); // Turns off WP 6.0's stopgap handler for Webfonts API.

packages/block-library/src/template-part/edit/advanced-controls.js

@@ -7,12 +7,18 @@ import { sprintf, __ } from '@wordpress/i18n';
 import { InspectorControls } from '@wordpress/block-editor';
 import { useSelect } from '@wordpress/data';
 
+/**
+ * Internal dependencies
+ */
+import { TemplatePartImportControls } from './import-controls';
+
 export function TemplatePartAdvancedControls( {
 	tagName,
 	setAttributes,
 	isEntityAvailable,
 	templatePartId,
 	defaultWrapper,
+	hasInnerBlocks,
 } ) {
 	const [ area, setArea ] = useEntityProp(
 		'postType',
@@ -87,6 +93,12 @@ export function TemplatePartAdvancedControls( {
 				value={ tagName || '' }
 				onChange={ ( value ) => setAttributes( { tagName: value } ) }
 			/>
+			{ ! hasInnerBlocks && (
+				<TemplatePartImportControls
+					area={ area }
+					setAttributes={ setAttributes }
+				/>
+			) }
 		</InspectorControls>
 	);
 }

packages/block-library/src/template-part/edit/import-controls.js

@@ -0,0 +1,180 @@
+/**
+ * WordPress dependencies
+ */
+import { __, sprintf } from '@wordpress/i18n';
+import { useMemo, useState } from '@wordpress/element';
+import { useDispatch, useSelect, useRegistry } from '@wordpress/data';
+import {
+	Button,
+	FlexBlock,
+	FlexItem,
+	SelectControl,
+	__experimentalHStack as HStack,
+	__experimentalSpacer as Spacer,
+} from '@wordpress/components';
+import {
+	switchToBlockType,
+	getPossibleBlockTransformations,
+} from '@wordpress/blocks';
+import { store as coreStore } from '@wordpress/core-data';
+import { store as noticesStore } from '@wordpress/notices';
+
+/**
+ * Internal dependencies
+ */
+import { useCreateTemplatePartFromBlocks } from './utils/hooks';
+import { transformWidgetToBlock } from './utils/transformers';
+
+export function TemplatePartImportControls( { area, setAttributes } ) {
+	const [ selectedSidebar, setSelectedSidebar ] = useState( '' );
+	const [ isBusy, setIsBusy ] = useState( false );
+
+	const registry = useRegistry();
+	const sidebars = useSelect( ( select ) => {
+		return select( coreStore ).getSidebars( {
+			per_page: -1,
+			_fields: 'id,name,description,status,widgets',
+		} );
+	}, [] );
+	const { createErrorNotice } = useDispatch( noticesStore );
+
+	const createFromBlocks = useCreateTemplatePartFromBlocks(
+		area,
+		setAttributes
+	);
+
+	const options = useMemo( () => {
+		const sidebarOptions = ( sidebars ?? [] )
+			.filter(
+				( widgetArea ) =>
+					widgetArea.id !== 'wp_inactive_widgets' &&
+					widgetArea.widgets.length > 0
+			)
+			.map( ( widgetArea ) => {
+				return {
+					value: widgetArea.id,
+					label: widgetArea.name,
+				};
+			} );
+
+		if ( ! sidebarOptions.length ) {
+			return [];
+		}
+
+		return [
+			{ value: '', label: __( 'Select widget area' ) },
+			...sidebarOptions,
+		];
+	}, [ sidebars ] );
+
+	async function createFromWidgets( event ) {
+		event.preventDefault();
+
+		if ( isBusy || ! selectedSidebar ) {
+			return;
+		}
+
+		setIsBusy( true );
+
+		const sidebar = options.find(
+			( { value } ) => value === selectedSidebar
+		);
+		const { getWidgets } = registry.resolveSelect( coreStore );
+
+		// The widgets API always returns a successful response.
+		const widgets = await getWidgets( {
+			sidebar: sidebar.value,
+			_embed: 'about',
+		} );
+
+		const skippedWidgets = new Set();
+		const blocks = widgets.flatMap( ( widget ) => {
+			const block = transformWidgetToBlock( widget );
+
+			if ( block.name !== 'core/legacy-widget' ) {
+				return 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( '*' )
+				);
+
+				return ! hasWildCardFrom && ! hasWildCardTo;
+			} );
+
+			// Skip the block if we have no matching transformations.
+			if ( ! transforms.length ) {
+				skippedWidgets.add( widget.id_base );
+				return [];
+			}
+
+			// Try transforming the Legacy Widget into a first matching block.
+			return switchToBlockType( block, transforms[ 0 ].name );
+		} );
+
+		await createFromBlocks(
+			blocks,
+			/* translators: %s: name of the widget area */
+			sprintf( __( 'Widget area: %s' ), sidebar.label )
+		);
+
+		if ( skippedWidgets.size ) {
+			createErrorNotice(
+				sprintf(
+					/* translators: %s: the list of widgets */
+					__( 'Unable to import the following widgets: %s.' ),
+					Array.from( skippedWidgets ).join( ', ' )
+				),
+				{
+					type: 'snackbar',
+				}
+			);
+		}
+
+		setIsBusy( false );
+	}
+
+	return (
+		<Spacer marginBottom="4">
+			<HStack as="form" onSubmit={ createFromWidgets }>
+				<FlexBlock>
+					<SelectControl
+						label={ __( 'Import widget area' ) }
+						value={ selectedSidebar }
+						options={ options }
+						onChange={ ( value ) => setSelectedSidebar( value ) }
+						disabled={ ! options.length }
+						__next36pxDefaultSize
+						__nextHasNoMarginBottom
+					/>
+				</FlexBlock>
+				<FlexItem
+					style={ {
+						marginBottom: '8px',
+						marginTop: 'auto',
+					} }
+				>
+					<Button
+						variant="primary"
+						type="submit"
+						isBusy={ isBusy }
+						aria-disabled={ isBusy || ! selectedSidebar }
+					>
+						{ __( 'Import' ) }
+					</Button>
+				</FlexItem>
+			</HStack>
+		</Spacer>
+	);
+}

packages/block-library/src/template-part/edit/index.js

@@ -141,6 +141,7 @@ export default function TemplatePartEdit( {
 					isEntityAvailable={ isEntityAvailable }
 					templatePartId={ templatePartId }
 					defaultWrapper={ areaObject.tagName }
+					hasInnerBlocks={ innerBlocks.length > 0 }
 				/>
 				{ isPlaceholder && (
 					<TagName { ...blockProps }>

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

@@ -0,0 +1,37 @@
+/**
+ * WordPress dependencies
+ */
+import { createBlock, parse } 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' ) {
+		const parsedBlocks = parse( widget.instance.raw.content, {
+			__unstableSkipAutop: true,
+		} );
+		if ( ! parsedBlocks.length ) {
+			return createBlock( 'core/paragraph', {}, [] );
+		}
+
+		return parsedBlocks[ 0 ];
+	}
+
+	let attributes;
+	if ( widget._embedded.about[ 0 ].is_multi ) {
+		attributes = {
+			idBase: widget.id_base,
+			instance: widget.instance,
+		};
+	} else {
+		attributes = {
+			id: widget.id,
+		};
+	}
+
+	return createBlock( 'core/legacy-widget', attributes, [] );
+}

packages/edit-post/package.json

@@ -52,6 +52,7 @@
 		"@wordpress/url": "file:../url",
 		"@wordpress/viewport": "file:../viewport",
 		"@wordpress/warning": "file:../warning",
+		"@wordpress/widgets": "file:../widgets",
 		"classnames": "^2.3.1",
 		"lodash": "^4.17.21",
 		"memize": "^1.1.0",

packages/edit-post/src/index.js

@@ -10,6 +10,7 @@ import { render, unmountComponentAtNode } from '@wordpress/element';
 import { dispatch, select } from '@wordpress/data';
 import { addFilter } from '@wordpress/hooks';
 import { store as preferencesStore } from '@wordpress/preferences';
+import { registerLegacyWidgetBlock } from '@wordpress/widgets';
 
 /**
  * Internal dependencies
@@ -115,6 +116,7 @@ export function initializeEditor(
 	}
 
 	registerCoreBlocks();
+	registerLegacyWidgetBlock( { inserter: false } );
 	if ( process.env.IS_GUTENBERG_PLUGIN ) {
 		__experimentalRegisterExperimentalCoreBlocks( {
 			enableFSEBlocks: settings.__unstableEnableFullSiteEditingBlocks,

packages/edit-site/package.json

@@ -54,6 +54,7 @@
 		"@wordpress/style-engine": "file:../style-engine",
 		"@wordpress/url": "file:../url",
 		"@wordpress/viewport": "file:../viewport",
+		"@wordpress/widgets": "file:../widgets",
 		"classnames": "^2.3.1",
 		"colord": "^2.9.2",
 		"downloadjs": "^1.4.7",