/** * @license Copyright (c) 2003-2016, CKSource - Frederico Knabben. All rights reserved. * For licensing, see LICENSE.md. */ /** * `TextProxy` represents a part of {@link engine.model.Text text node}. * * Since {@link engine.model.Position positions} can be placed between characters of a text node, * {@link engine.model.Range ranges} may contain only parts of text nodes. When {@link engine.model.Range#getItems getting items} * contained in such range, we need to represent a part of that text node, since returning the whole text node would be incorrect. * `TextProxy` solves this issue. * * `TextProxy` has an API similar to {@link engine.model.Text Text} and allows to do most of the common tasks performed * on model nodes. * * **Note:** Some `TextProxy` instances may represent whole text node, not just a part of it. * * **Note:** `TextProxy` is not an instance of {@link engine.model.Node node}. Keep this in mind when using it as a * parameter of methods. * * **Note:** `TextProxy` is readonly interface. If you want to perform changes on model data represented by a `TextProxy` * use {@link engine.model.writer model writer API}. * * **Note:** `TextProxy` instances are created on the fly, basing on the current state of model. Because of this, it is * highly unrecommended to store references to `TextProxy` instances. `TextProxy` instances are not refreshed when * model changes, so they might get invalidated. Instead, consider creating {@link engine.model.LivePosition live position}. * * `TextProxy` instances are created by {@link engine.model.TreeWalker model tree walker}. You should not need to create * an instance of this class by your own. * * @memberOf engine.model */ export default class TextProxy { /** * Creates a text proxy. * * @protected * @param {engine.model.Text} textNode Text node which part is represented by this text proxy. * @param {Number} offsetInText Offset in {@link engine.model.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 ) { /** * Text node which part is represented by this text proxy. * * @readonly * @member {engine.model.Text} engine.model.TextProxy#textNode */ this.textNode = textNode; /** * Text data represented by this text proxy. * * @readonly * @member {String} engine.model.TextProxy#data */ this.data = textNode.data.substring( offsetInText, offsetInText + length ); /** * Offset in {@link engine.model.TextProxy#textNode text node} from which the text proxy starts. * * @readonly * @member {Number} engine.model.TextProxy#offsetInText */ this.offsetInText = offsetInText; } /** * Offset at which this text proxy starts in it's parent. * * @see engine.model.Node#startOffset * @readonly * @type {Number} */ get startOffset() { return this.textNode.startOffset !== null ? this.textNode.startOffset + this.offsetInText : null; } /** * Offset size of this text proxy. Equal to the number of characters represented by the text proxy. * * @see engine.model.Node#offsetSize * @readonly * @type {Number} */ get offsetSize() { return this.data.length; } /** * Offset at which this text proxy ends in it's parent. * * @see engine.model.Node#endOffset * @readonly * @type {Number} */ get endOffset() { return this.startOffset !== null ? this.startOffset + this.offsetSize : null; } /** * Flag indicating whether `TextProxy` instance covers only part of the original {@link engine.model.Text text node} * (`true`) or the whole text node (`false`). * * This is `false` when text proxy starts at the very beginning of {@link engine.model.TextProxy#textNode textNode} * ({@link engine.model.TextProxy#offsetInText offsetInText} equals `0`) and text proxy sizes is equal to * text node size. * * @readonly * @type {Boolean} */ get isPartial() { return this.offsetInText !== 0 || this.offsetSize !== this.textNode.offsetSize; } /** * Parent of this text proxy, which is same as parent of text node represented by this text proxy. * * @readonly * @type {engine.model.Element|engine.model.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 {engine.model.Node|engine.model.DocumentFragment} */ get root() { return this.textNode.root; } /** * {@link engine.model.Document Document} that owns text node represented by this text proxy or `null` if the text node * has no parent or is inside a {@link engine.model.DocumentFragment DocumentFragment}. * * @readonly * @type {engine.model.Document|null} */ get document() { return this.textNode.document; } /** * Gets path to this text proxy. * * @see engine.model.Node#getPath * @readonly * @type {Array.} */ getPath() { const path = this.textNode.getPath(); if ( path.length > 0 ) { path[ path.length - 1 ] += this.offsetInText; } return path; } /** * Returns ancestors array of this text proxy. * * @param {Object} options Options object. * @param {Boolean} [options.includeNode=false] When set to `true` this text proxy 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 = { includeNode: false, parentFirst: false } ) { const ancestors = []; let parent = options.includeNode ? this : this.parent; while ( parent ) { ancestors[ options.parentFirst ? 'push' : 'unshift' ]( parent ); parent = parent.parent; } return ancestors; } /** * Checks if this text proxy has an attribute for given key. * * @param {String} key Key of attribute to check. * @returns {Boolean} `true` if attribute with given key is set on text proxy, `false` otherwise. */ hasAttribute( key ) { return this.textNode.hasAttribute( key ); } /** * Gets an attribute value for given key or `undefined` if that attribute is not set on text proxy. * * @param {String} key Key of attribute to look for. * @returns {*} Attribute value or `undefined`. */ getAttribute( key ) { return this.textNode.getAttribute( key ); } /** * Returns iterator that iterates over this node's attributes. Attributes are returned as arrays containing two * items. First one is attribute key and second is attribute value. * * This format is accepted by native `Map` object and also can be passed in `Node` constructor. * * @returns {Iterable.<*>} */ getAttributes() { return this.textNode.getAttributes(); } /** * Returns iterator that iterates over this node's attribute keys. * * @returns {Iterator.} */ getAttributeKeys() { return this.textNode.getAttributeKeys(); } }