[Document list] GHS integration

packages/ckeditor5-html-support/src/generalhtmlsupport.js

@@ -18,6 +18,7 @@ import MediaEmbedElementSupport from './integrations/mediaembed';
 import ScriptElementSupport from './integrations/script';
 import TableElementSupport from './integrations/table';
 import StyleElementSupport from './integrations/style';
+import DocumentListElementSupport from './integrations/documentlist';
 
 /**
  * The General HTML Support feature.
@@ -48,7 +49,8 @@ export default class GeneralHtmlSupport extends Plugin {
 			MediaEmbedElementSupport,
 			ScriptElementSupport,
 			TableElementSupport,
-			StyleElementSupport
+			StyleElementSupport,
+			DocumentListElementSupport
 		];
 	}
 

packages/ckeditor5-html-support/src/integrations/documentlist.js

@@ -0,0 +1,189 @@
+/**
+ * @license Copyright (c) 2003-2022, CKSource Holding sp. z o.o. All rights reserved.
+ * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
+ */
+
+/**
+ * @module html-support/integrations/documentlist
+ */
+
+import { isEqual } from 'lodash-es';
+import { Plugin } from 'ckeditor5/src/core';
+import { setViewAttributes } from '../conversionutils.js';
+
+import DataFilter from '../datafilter';
+
+/**
+ * Provides the General HTML Support integration with {@link module:list/documentlist~DocumentList Document List} feature.
+ *
+ * @extends module:core/plugin~Plugin
+ */
+export default class DocumentListElementSupport extends Plugin {
+	/**
+	 * @inheritDoc
+	 */
+	static get requires() {
+		return [ DataFilter ];
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	init() {
+		const editor = this.editor;
+
+		if ( !editor.plugins.has( 'DocumentListEditing' ) ) {
+			return;
+		}
+
+		const schema = editor.model.schema;
+		const conversion = editor.conversion;
+		const dataFilter = editor.plugins.get( DataFilter );
+		const documentListEditing = editor.plugins.get( 'DocumentListEditing' );
+
+		// Register downcast strategy.
+		// Note that this must be done before document list editing registers conversion in afterInit.
+		documentListEditing.registerDowncastStrategy( {
+			scope: 'item',
+			attributeName: 'htmlLiAttributes',
+
+			setAttributeOnDowncast( writer, attributeValue, viewElement ) {
+				setViewAttributes( writer, attributeValue, viewElement );
+			}
+		} );
+
+		documentListEditing.registerDowncastStrategy( {
+			scope: 'list',
+			attributeName: 'htmlListAttributes',
+
+			setAttributeOnDowncast( writer, viewAttributes, viewElement ) {
+				setViewAttributes( writer, viewAttributes, viewElement );
+			}
+		} );
+
+		dataFilter.on( 'register', ( evt, definition ) => {
+			if ( ![ 'ul', 'ol', 'li' ].includes( definition.view ) ) {
+				return;
+			}
+
+			evt.stop();
+
+			// Do not register same converters twice.
+			if ( schema.checkAttribute( '$block', 'htmlListAttributes' ) ) {
+				return;
+			}
+
+			schema.extend( '$block', { allowAttributes: [ 'htmlListAttributes', 'htmlLiAttributes' ] } );
+			schema.extend( '$blockObject', { allowAttributes: [ 'htmlListAttributes', 'htmlLiAttributes' ] } );
+			schema.extend( '$container', { allowAttributes: [ 'htmlListAttributes', 'htmlLiAttributes' ] } );
+
+			conversion.for( 'upcast' ).add( dispatcher => {
+				dispatcher.on( 'element:ul', viewToModelListAttributeConverter( 'htmlListAttributes', dataFilter ), { priority: 'low' } );
+				dispatcher.on( 'element:ol', viewToModelListAttributeConverter( 'htmlListAttributes', dataFilter ), { priority: 'low' } );
+				dispatcher.on( 'element:li', viewToModelListAttributeConverter( 'htmlLiAttributes', dataFilter ), { priority: 'low' } );
+			} );
+		} );
+
+		// Reset list attributes after indenting list items.
+		this.listenTo( editor.commands.get( 'indentList' ), 'afterExecute', ( evt, changedBlocks ) => {
+			editor.model.change( writer => {
+				for ( const node of changedBlocks ) {
+					// Just reset the attribute.
+					// If there is a previous indented list that this node should be merged into,
+					// the postfixer will unify all the attributes of both sub-lists.
+					writer.setAttribute( 'htmlListAttributes', {}, node );
+				}
+			} );
+		} );
+
+		// Make sure that all items in a single list (items at the same level & listType) have the same properties.
+		// Note: This is almost exact copy from DocumentListPropertiesEditing.
+		documentListEditing.on( 'postFixer', ( evt, { listNodes, writer } ) => {
+			const previousNodesByIndent = []; // Last seen nodes of lower indented lists.
+
+			for ( const { node, previous } of listNodes ) {
+				// For the first list block there is nothing to compare with.
+				if ( !previous ) {
+					continue;
+				}
+
+				const nodeIndent = node.getAttribute( 'listIndent' );
+				const previousNodeIndent = previous.getAttribute( 'listIndent' );
+
+				let previousNodeInList = null; // It's like `previous` but has the same indent as current node.
+
+				// Let's find previous node for the same indent.
+				// We're going to need that when we get back to previous indent.
+				if ( nodeIndent > previousNodeIndent ) {
+					previousNodesByIndent[ previousNodeIndent ] = previous;
+				}
+				// Restore the one for given indent.
+				else if ( nodeIndent < previousNodeIndent ) {
+					previousNodeInList = previousNodesByIndent[ nodeIndent ];
+					previousNodesByIndent.length = nodeIndent;
+				}
+				// Same indent.
+				else {
+					previousNodeInList = previous;
+				}
+
+				// This is a first item of a nested list.
+				if ( !previousNodeInList ) {
+					continue;
+				}
+
+				if ( previousNodeInList.getAttribute( 'listType' ) == node.getAttribute( 'listType' ) ) {
+					const value = previousNodeInList.getAttribute( 'htmlListAttributes' );
+
+					if ( !isEqual( node.getAttribute( 'htmlListAttributes' ), value ) ) {
+						writer.setAttribute( 'htmlListAttributes', value, node );
+						evt.return = true;
+					}
+				}
+
+				if ( previousNodeInList.getAttribute( 'listItemId' ) == node.getAttribute( 'listItemId' ) ) {
+					const value = previousNodeInList.getAttribute( 'htmlLiAttributes' );
+
+					if ( !isEqual( node.getAttribute( 'htmlLiAttributes' ), value ) ) {
+						writer.setAttribute( 'htmlLiAttributes', value, node );
+						evt.return = true;
+					}
+				}
+			}
+		} );
+	}
+}
+
+// View-to-model conversion helper preserving allowed attributes on {@link TODO}
+// feature model element.
+//
+// @private
+// @param {String} attributeName
+// @param {module:html-support/datafilter~DataFilter} dataFilter
+// @returns {Function} Returns a conversion callback.
+function viewToModelListAttributeConverter( attributeName, dataFilter ) {
+	return ( evt, data, conversionApi ) => {
+		const viewElement = data.viewItem;
+
+		if ( !data.modelRange ) {
+			Object.assign( data, conversionApi.convertChildren( data.viewItem, data.modelCursor ) );
+		}
+
+		const viewAttributes = dataFilter._consumeAllowedAttributes( viewElement, conversionApi );
+
+		for ( const item of data.modelRange.getItems( { shallow: true } ) ) {
+			// Apply only to list item blocks.
+			if ( !item.hasAttribute( 'listItemId' ) ) {
+				continue;
+			}
+
+			// Set list attributes only on same level items, those nested deeper are already handled
+			// by the recursive conversion.
+			if ( item.hasAttribute( attributeName ) ) {
+				continue;
+			}
+
+			conversionApi.writer.setAttribute( attributeName, viewAttributes || {}, item );
+		}
+	};
+}