src/view/textproxy.js
/**
* @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/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 this object is of the given type.
*
* textProxy.is( 'textProxy' ); // -> true
* textProxy.is( 'view:textProxy' ); // -> true
*
* textProxy.is( 'model:textProxy' ); // -> false
* textProxy.is( 'element' ); // -> false
* textProxy.is( 'range' ); // -> false
*
* {@link module:engine/view/node~Node#is Check the entire list of view objects} which implement the `is()` method.
*
* @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;
}
// @if CK_DEBUG_ENGINE // toString() {
// @if CK_DEBUG_ENGINE // return `#${ this.data }`;
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // log() {
// @if CK_DEBUG_ENGINE // console.log( 'ViewTextProxy: ' + this );
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // logExtended() {
// @if CK_DEBUG_ENGINE // console.log( 'ViewTextProxy: ' + this );
// @if CK_DEBUG_ENGINE // }
}