/** * @license Copyright (c) 2003-2019, CKSource - Frederico Knabben. All rights reserved. * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license */ /** * @module engine/view/textproxy */ import CKEditorError from '@ckeditor/ckeditor5-utils/src/ckeditorerror'; /** * TextProxy is a wrapper for substring of {@link module:engine/view/text~Text}. Instance of this class is created by * {@link module:engine/view/treewalker~TreeWalker} when only a part of {@link module:engine/view/text~Text} needs to be returned. * * `TextProxy` has an API similar to {@link module:engine/view/text~Text Text} and allows to do most of the common tasks performed * on view nodes. * * **Note:** Some `TextProxy` instances may represent whole text node, not just a part of it. * See {@link module:engine/view/textproxy~TextProxy#isPartial}. * * **Note:** `TextProxy` is a readonly interface. * * **Note:** `TextProxy` instances are created on the fly basing on the current state of parent {@link module:engine/view/text~Text}. * Because of this it is highly unrecommended to store references to `TextProxy instances because they might get * invalidated due to operations on Document. Also TextProxy is not a {@link module:engine/view/node~Node} so it can not be * inserted as a child of {@link module:engine/view/element~Element}. * * `TextProxy` instances are created by {@link module:engine/view/treewalker~TreeWalker view tree walker}. You should not need to create * an instance of this class by your own. */ export default class TextProxy { /** * Creates a text proxy. * * @protected * @param {module:engine/view/text~Text} textNode Text node which part is represented by this text proxy. * @param {Number} offsetInText Offset in {@link module:engine/view/textproxy~TextProxy#textNode text node} * from which the text proxy starts. * @param {Number} length Text proxy length, that is how many text node's characters, starting from `offsetInText` it represents. * @constructor */ constructor( textNode, offsetInText, length ) { /** * Reference to the {@link module:engine/view/text~Text} element which TextProxy is a substring. * * @readonly * @member {module:engine/view/text~Text} module:engine/view/textproxy~TextProxy#textNode */ this.textNode = textNode; if ( offsetInText < 0 || offsetInText > textNode.data.length ) { /** * Given offsetInText value is incorrect. * * @error view-textproxy-wrong-offsetintext */ throw new CKEditorError( 'view-textproxy-wrong-offsetintext: Given offsetInText value is incorrect.', this ); } if ( length < 0 || offsetInText + length > textNode.data.length ) { /** * Given length value is incorrect. * * @error view-textproxy-wrong-length */ throw new CKEditorError( 'view-textproxy-wrong-length: Given length value is incorrect.', this ); } /** * Text data represented by this text proxy. * * @readonly * @member {String} module:engine/view/textproxy~TextProxy#data */ this.data = textNode.data.substring( offsetInText, offsetInText + length ); /** * Offset in the `textNode` where this `TextProxy` instance starts. * * @readonly * @member {Number} module:engine/view/textproxy~TextProxy#offsetInText */ this.offsetInText = offsetInText; } /** * Offset size of this node. * * @readonly * @type {Number} */ get offsetSize() { return this.data.length; } /** * Flag indicating whether `TextProxy` instance covers only part of the original {@link module:engine/view/text~Text text node} * (`true`) or the whole text node (`false`). * * This is `false` when text proxy starts at the very beginning of {@link module:engine/view/textproxy~TextProxy#textNode textNode} * ({@link module:engine/view/textproxy~TextProxy#offsetInText offsetInText} equals `0`) and text proxy sizes is equal to * text node size. * * @readonly * @type {Boolean} */ get isPartial() { return this.data.length !== this.textNode.data.length; } /** * Parent of this text proxy, which is same as parent of text node represented by this text proxy. * * @readonly * @type {module:engine/view/element~Element|module:engine/view/documentfragment~DocumentFragment|null} */ get parent() { return this.textNode.parent; } /** * Root of this text proxy, which is same as root of text node represented by this text proxy. * * @readonly * @type {module:engine/view/node~Node|module:engine/view/documentfragment~DocumentFragment} */ get root() { return this.textNode.root; } /** * {@link module:engine/view/document~Document View document} that owns this text proxy, or `null` if the text proxy is inside * {@link module:engine/view/documentfragment~DocumentFragment document fragment}. * * @readonly * @type {module:engine/view/document~Document|null} */ get document() { return this.textNode.document; } /** * Checks whether given view tree object is of given type following the convention set by * {@link module:engine/view/node~Node#is `Node#is()`}. * * @param {String} type * @returns {Boolean} */ is( type ) { return type == 'textProxy' || type == 'view:textProxy'; } /** * Returns ancestors array of this text proxy. * * @param {Object} options Options object. * @param {Boolean} [options.includeSelf=false] When set to `true` {#textNode} will be also included in parent's array. * @param {Boolean} [options.parentFirst=false] When set to `true`, array will be sorted from text proxy parent to * root element, otherwise root element will be the first item in the array. * @returns {Array} Array with ancestors. */ getAncestors( options = { includeSelf: false, parentFirst: false } ) { const ancestors = []; let parent = options.includeSelf ? this.textNode : this.parent; while ( parent !== null ) { ancestors[ options.parentFirst ? 'push' : 'unshift' ]( parent ); parent = parent.parent; } return ancestors; } }