/** * @license Copyright (c) 2003-2017, CKSource - Frederico Knabben. All rights reserved. * For licensing, see LICENSE.md. */ /** * @module engine/model/operation/rootattributeoperation */ import Operation from './operation'; import CKEditorError from '@ckeditor/ckeditor5-utils/src/ckeditorerror'; /** * Operation to change root element's attribute. Using this class you can add, remove or change value of the attribute. * * This operation is needed, because root elements can't be changed through * @link module:engine/model/operation/attributeoperation~AttributeOperation}. * It is because {@link module:engine/model/operation/attributeoperation~AttributeOperation} * requires a range to change and root element can't * be a part of range because every {@link module:engine/model/position~Position} has to be inside a root. * {@link module:engine/model/position~Position} can't be created before a root element. * * @extends module:engine/model/operation/operation~Operation */ export default class RootAttributeOperation extends Operation { /** * Creates an operation that changes, removes or adds attributes on root element. * * @see module:engine/model/operation/attributeoperation~AttributeOperation * @param {module:engine/model/rootelement~RootElement} root Root element to change. * @param {String} key Key of an attribute to change or remove. * @param {*} oldValue Old value of the attribute with given key or `null` if adding a new attribute. * @param {*} newValue New value to set for the attribute. If `null`, then the operation just removes the attribute. * @param {Number} baseVersion {@link module:engine/model/document~Document#version} on which the operation can be applied. */ constructor( root, key, oldValue, newValue, baseVersion ) { super( baseVersion ); /** * Root element to change. * * @readonly * @member {module:engine/model/rootelement~RootElement} */ this.root = root; /** * Key of an attribute to change or remove. * * @readonly * @member {String} */ this.key = key; /** * Old value of the attribute with given key or `null` if adding a new attribute. * * @readonly * @member {*} */ this.oldValue = oldValue; /** * New value to set for the attribute. If `null`, then the operation just removes the attribute. * * @readonly * @member {*} */ this.newValue = newValue; } get type() { if ( this.oldValue === null ) { return 'addRootAttribute'; } else if ( this.newValue === null ) { return 'removeRootAttribute'; } else { return 'changeRootAttribute'; } } /** * @returns {module:engine/model/operation/rootattributeoperation~RootAttributeOperation} */ clone() { return new RootAttributeOperation( this.root, this.key, this.oldValue, this.newValue, this.baseVersion ); } /** * @returns {module:engine/model/operation/rootattributeoperation~RootAttributeOperation} */ getReversed() { return new RootAttributeOperation( this.root, this.key, this.newValue, this.oldValue, this.baseVersion + 1 ); } _execute() { if ( this.oldValue !== null && this.root.getAttribute( this.key ) !== this.oldValue ) { /** * The attribute which should be removed does not exists for the given node. * * @error rootattribute-operation-wrong-old-value * @param {module:engine/model/rootelement~RootElement} root * @param {String} key * @param {*} value */ throw new CKEditorError( 'rootattribute-operation-wrong-old-value: Changed node has different attribute value than operation\'s old attribute value.', { root: this.root, key: this.key } ); } if ( this.oldValue === null && this.newValue !== null && this.root.hasAttribute( this.key ) ) { /** * The attribute with given key already exists for the given node. * * @error rootattribute-operation-attribute-exists * @param {module:engine/model/rootelement~RootElement} root * @param {String} key */ throw new CKEditorError( 'rootattribute-operation-attribute-exists: The attribute with given key already exists.', { root: this.root, key: this.key } ); } if ( this.newValue !== null ) { this.root.setAttribute( this.key, this.newValue ); } else { this.root.removeAttribute( this.key ); } return { root: this.root, key: this.key, oldValue: this.oldValue, newValue: this.newValue }; } /** * @inheritDoc */ static get className() { return 'engine.model.operation.RootAttributeOperation'; } /** * Creates RootAttributeOperation object from deserilized object, i.e. from parsed JSON string. * * @param {Object} json Deserialized JSON object. * @param {module:engine/model/document~Document} document Document on which this operation will be applied. * @returns {module:engine/model/operation/rootattributeoperation~RootAttributeOperation} */ static fromJSON( json, document ) { if ( !document.hasRoot( json.root ) ) { /** * Cannot create RootAttributeOperation for document. Root with specified name does not exist. * * @error rootattributeoperation-fromjson-no-root * @param {String} rootName */ throw new CKEditorError( 'rootattribute-operation-fromjson-no-root: Cannot create RootAttributeOperation. Root with specified name does not exist.', { rootName: json } ); } return new RootAttributeOperation( document.getRoot( json.root ), json.key, json.oldValue, json.newValue, json.baseVersion ); } }