/**
* @license Copyright (c) 2003-2016, CKSource - Frederico Knabben. All rights reserved.
* For licensing, see LICENSE.md.
*/
import Observer from '../engine/view/observer/observer.js';
import DomEventData from '../engine/view/observer/domeventdata.js';
import { keyCodes } from '../utils/keyboard.js';
/**
* Delete observer introduces the {@link engine.view.Document#delete} event.
*
* @memberOf typing
* @extends engine.view.observer.Observer
*/
export default class DeleteObserver extends Observer {
constructor( document ) {
super( document );
document.on( 'keydown', ( evt, data ) => {
const deleteData = {};
if ( data.keyCode == keyCodes.delete ) {
deleteData.direction = 'forward';
} else if ( data.keyCode == keyCodes.backspace ) {
deleteData.direction = 'backward';
} else {
return;
}
deleteData.unit = data.altKey ? 'word' : 'character';
document.fire( 'delete', new DomEventData( document, data.domEvent, deleteData ) );
} );
}
/**
* @inheritDoc
*/
observe() {}
}
/**
* Event fired when the user tries to delete content (e.g. presses Delete or Backspace).
*
* Note: This event is fired by the {@link typing.DeleteObserver observer}
* (usually registered by the {@link typing.Delete delete feature}).
*
* @event engine.view.Document#delete
* @param {engine.view.observer.DomEventData} data
* @param {'forward'|'delete'} data.direction The direction in which the deletion should happen.
* @param {'character'|'word'} data.unit The "amount" of content that should be deleted.
*/