ckeditor/ckeditor5-engine

/**
 * @license Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */

/**
 * @module engine/model/operation/renameoperation
 */

import Operation from './operation';
import Element from '../element';
import CKEditorError from '@ckeditor/ckeditor5-utils/src/ckeditorerror';
import Position from '../position';

/**
 * Operation to change element's name.
 *
 * Using this class you can change element's name.
 *
 * @extends module:engine/model/operation/operation~Operation
 */
export default class RenameOperation extends Operation {
    /**
     * Creates an operation that changes element's name.
     *
     * @param {module:engine/model/position~Position} position Position before an element to change.
     * @param {String} oldName Current name of the element.
     * @param {String} newName New name for the element.
     * @param {Number|null} baseVersion Document {@link module:engine/model/document~Document#version} on which operation
     * can be applied or `null` if the operation operates on detached (non-document) tree.
     */
    constructor( position, oldName, newName, baseVersion ) {
        super( baseVersion );

        /**
         * Position before an element to change.
         *
         * @member {module:engine/model/position~Position} module:engine/model/operation/renameoperation~RenameOperation#position
         */
        this.position = position;
        // This position sticks to the next node because it is a position before the node that we want to change.
        this.position.stickiness = 'toNext';

        /**
         * Current name of the element.
         *
         * @member {String} module:engine/model/operation/renameoperation~RenameOperation#oldName
         */
        this.oldName = oldName;

        /**
         * New name for the element.
         *
         * @member {String} module:engine/model/operation/renameoperation~RenameOperation#newName
         */
        this.newName = newName;
    }

    /**
     * @inheritDoc
     */
    get type() {
        return 'rename';
    }

    /**
     * Creates and returns an operation that has the same parameters as this operation.
     *
     * @returns {module:engine/model/operation/renameoperation~RenameOperation} Clone of this operation.
     */
    clone() {
        return new RenameOperation( this.position.clone(), this.oldName, this.newName, this.baseVersion );
    }

    /**
     * See {@link module:engine/model/operation/operation~Operation#getReversed `Operation#getReversed()`}.
     *
     * @returns {module:engine/model/operation/renameoperation~RenameOperation}
     */
    getReversed() {
        return new RenameOperation( this.position.clone(), this.newName, this.oldName, this.baseVersion + 1 );
    }

    /**
     * @inheritDoc
     */
    _validate() {
        const element = this.position.nodeAfter;

        if ( !( element instanceof Element ) ) {
            /**
             * Given position is invalid or node after it is not instance of Element.
             *
             * @error rename-operation-wrong-position
             */
            throw new CKEditorError(
                'rename-operation-wrong-position: Given position is invalid or node after it is not an instance of Element.',
                this
            );
        } else if ( element.name !== this.oldName ) {
            /**
             * Element to change has different name than operation's old name.
             *
             * @error rename-operation-wrong-name
             */
            throw new CKEditorError(
                'rename-operation-wrong-name: Element to change has different name than operation\'s old name.',
                this
            );
        }
    }

    /**
     * @inheritDoc
     */
    _execute() {
        const element = this.position.nodeAfter;

        element.name = this.newName;
    }

    /**
     * @inheritDoc
     */
    toJSON() {
        const json = super.toJSON();

        json.position = this.position.toJSON();

        return json;
    }

    /**
     * @inheritDoc
     */
    static get className() {
        return 'RenameOperation';
    }

    /**
     * Creates `RenameOperation` object from deserialized 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/attributeoperation~AttributeOperation}
     */
    static fromJSON( json, document ) {
        return new RenameOperation( Position.fromJSON( json.position, document ), json.oldName, json.newName, json.baseVersion );
    }

    // @if CK_DEBUG_ENGINE // toString() {
    // @if CK_DEBUG_ENGINE //     return `RenameOperation( ${ this.baseVersion } ): ` +
    // @if CK_DEBUG_ENGINE //        `${ this.position }: "${ this.oldName }" -> "${ this.newName }"`;
    // @if CK_DEBUG_ENGINE // }
}