src/model/operation/splitoperation.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/model/operation/splitoperation
*/
import Operation from './operation';
import MergeOperation from './mergeoperation';
import Position from '../position';
import Range from '../range';
import { _insert, _move } from './utils';
import CKEditorError from '@ckeditor/ckeditor5-utils/src/ckeditorerror';
/**
* Operation to split {@link module:engine/model/element~Element an element} at given
* {@link module:engine/model/operation/splitoperation~SplitOperation#splitPosition split position} into two elements,
* both containing a part of the element's original content.
*
* @extends module:engine/model/operation/operation~Operation
*/
export default class SplitOperation extends Operation {
/**
* Creates a split operation.
*
* @param {module:engine/model/position~Position} splitPosition Position at which an element should be split.
* @param {Number} howMany Total offset size of elements that are in the split element after `position`.
* @param {module:engine/model/position~Position|null} graveyardPosition Position in the graveyard root before the element which
* should be used as a parent of the nodes after `position`. If it is not set, a copy of the the `position` parent will be used.
* @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( splitPosition, howMany, graveyardPosition, baseVersion ) {
super( baseVersion );
/**
* Position at which an element should be split.
*
* @member {module:engine/model/position~Position} module:engine/model/operation/splitoperation~SplitOperation#splitPosition
*/
this.splitPosition = splitPosition.clone();
// Keep position sticking to the next node. This way any new content added at the place where the element is split
// will be left in the original element.
this.splitPosition.stickiness = 'toNext';
/**
* Total offset size of elements that are in the split element after `position`.
*
* @member {Number} module:engine/model/operation/splitoperation~SplitOperation#howMany
*/
this.howMany = howMany;
/**
* Position at which the clone of split element (or element from graveyard) will be inserted.
*
* @member {module:engine/model/position~Position} module:engine/model/operation/splitoperation~SplitOperation#insertionPosition
*/
this.insertionPosition = SplitOperation.getInsertionPosition( splitPosition );
this.insertionPosition.stickiness = 'toNone';
/**
* Position in the graveyard root before the element which should be used as a parent of the nodes after `position`.
* If it is not set, a copy of the the `position` parent will be used.
*
* The default behavior is to clone the split element. Element from graveyard is used during undo.
*
* @member {module:engine/model/position~Position|null} #graveyardPosition
*/
this.graveyardPosition = graveyardPosition ? graveyardPosition.clone() : null;
if ( this.graveyardPosition ) {
this.graveyardPosition.stickiness = 'toNext';
}
}
/**
* @inheritDoc
*/
get type() {
return 'split';
}
/**
* Position inside the new clone of a split element.
*
* This is a position where nodes that are after the split position will be moved to.
*
* @readonly
* @type {module:engine/model/position~Position}
*/
get moveTargetPosition() {
const path = this.insertionPosition.path.slice();
path.push( 0 );
return new Position( this.insertionPosition.root, path );
}
/**
* Artificial range that contains all the nodes from the split element that will be moved to the new element.
* The range starts at {@link ~#splitPosition} and ends in the same parent, at `POSITIVE_INFINITY` offset.
*
* @readonly
* @type {module:engine/model/range~Range}
*/
get movedRange() {
const end = this.splitPosition.getShiftedBy( Number.POSITIVE_INFINITY );
return new Range( this.splitPosition, end );
}
/**
* Creates and returns an operation that has the same parameters as this operation.
*
* @returns {module:engine/model/operation/splitoperation~SplitOperation} Clone of this operation.
*/
clone() {
const split = new this.constructor( this.splitPosition, this.howMany, this.graveyardPosition, this.baseVersion );
split.insertionPosition = this.insertionPosition;
return split;
}
/**
* See {@link module:engine/model/operation/operation~Operation#getReversed `Operation#getReversed()`}.
*
* @returns {module:engine/model/operation/mergeoperation~MergeOperation}
*/
getReversed() {
const graveyard = this.splitPosition.root.document.graveyard;
const graveyardPosition = new Position( graveyard, [ 0 ] );
return new MergeOperation( this.moveTargetPosition, this.howMany, this.splitPosition, graveyardPosition, this.baseVersion + 1 );
}
/**
* @inheritDoc
*/
_validate() {
const element = this.splitPosition.parent;
const offset = this.splitPosition.offset;
// Validate whether split operation has correct parameters.
if ( !element || element.maxOffset < offset ) {
/**
* Split position is invalid.
*
* @error split-operation-position-invalid
*/
throw new CKEditorError( 'split-operation-position-invalid: Split position is invalid.', this );
} else if ( !element.parent ) {
/**
* Cannot split root element.
*
* @error split-operation-split-in-root
*/
throw new CKEditorError( 'split-operation-split-in-root: Cannot split root element.', this );
} else if ( this.howMany != element.maxOffset - this.splitPosition.offset ) {
/**
* Split operation specifies wrong number of nodes to move.
*
* @error split-operation-how-many-invalid
*/
throw new CKEditorError( 'split-operation-how-many-invalid: Split operation specifies wrong number of nodes to move.', this );
} else if ( this.graveyardPosition && !this.graveyardPosition.nodeAfter ) {
/**
* Graveyard position invalid.
*
* @error split-operation-graveyard-position-invalid
*/
throw new CKEditorError( 'split-operation-graveyard-position-invalid: Graveyard position invalid.', this );
}
}
/**
* @inheritDoc
*/
_execute() {
const splitElement = this.splitPosition.parent;
if ( this.graveyardPosition ) {
_move( Range._createFromPositionAndShift( this.graveyardPosition, 1 ), this.insertionPosition );
} else {
const newElement = splitElement._clone();
_insert( this.insertionPosition, newElement );
}
const sourceRange = new Range(
Position._createAt( splitElement, this.splitPosition.offset ),
Position._createAt( splitElement, splitElement.maxOffset )
);
_move( sourceRange, this.moveTargetPosition );
}
/**
* @inheritDoc
*/
toJSON() {
const json = super.toJSON();
json.splitPosition = this.splitPosition.toJSON();
json.insertionPosition = this.insertionPosition.toJSON();
if ( this.graveyardPosition ) {
json.graveyardPosition = this.graveyardPosition.toJSON();
}
return json;
}
/**
* @inheritDoc
*/
static get className() {
return 'SplitOperation';
}
/**
* Helper function that returns a default insertion position basing on given `splitPosition`. The default insertion
* position is after the split element.
*
* @param {module:engine/model/position~Position} splitPosition
* @returns {module:engine/model/position~Position}
*/
static getInsertionPosition( splitPosition ) {
const path = splitPosition.path.slice( 0, -1 );
path[ path.length - 1 ]++;
return new Position( splitPosition.root, path );
}
/**
* Creates `SplitOperation` 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/splitoperation~SplitOperation}
*/
static fromJSON( json, document ) {
const splitPosition = Position.fromJSON( json.splitPosition, document );
const insertionPosition = Position.fromJSON( json.insertionPosition, document );
const graveyardPosition = json.graveyardPosition ? Position.fromJSON( json.graveyardPosition, document ) : null;
const split = new this( splitPosition, json.howMany, graveyardPosition, json.baseVersion );
split.insertionPosition = insertionPosition;
return split;
}
// @if CK_DEBUG_ENGINE // toString() {
// @if CK_DEBUG_ENGINE // return `SplitOperation( ${ this.baseVersion } ): ${ this.splitPosition } ` +
// @if CK_DEBUG_ENGINE // `( ${ this.howMany } ) -> ${ this.insertionPosition }` +
// @if CK_DEBUG_ENGINE // `${ this.graveyardPosition ? ' with ' + this.graveyardPosition : '' }`;
// @if CK_DEBUG_ENGINE // }
}