/**
 * @license
 * Copyright 2018 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @fileoverview Events fired as a result of UI actions in Blockly's editor.
 * @author fraser@google.com (Neil Fraser)
 */
'use strict';

goog.provide('Blockly.Events.Ui');

goog.require('Blockly.Events');
goog.require('Blockly.Events.Abstract');
goog.require('Blockly.utils.object');


/**
 * Class for a UI event.
 * UI events are events that don't need to be sent over the wire for multi-user
 * editing to work (e.g. scrolling the workspace, zooming, opening toolbox
 * categories).
 * UI events do not undo or redo.
 * @param {Blockly.Block} block The affected block.
 * @param {string} element One of 'selected', 'comment', 'mutatorOpen', etc.
 * @param {*} oldValue Previous value of element.
 * @param {*} newValue New value of element.
 * @extends {Blockly.Events.Abstract}
 * @constructor
 */
Blockly.Events.Ui = function(block, element, oldValue, newValue) {
  Blockly.Events.Ui.superClass_.constructor.call(this);
  this.blockId = block ? block.id : null;
  this.workspaceId = block ? block.workspace.id : undefined;
  this.element = element;
  this.oldValue = oldValue;
  this.newValue = newValue;
  // UI events do not undo or redo.
  this.recordUndo = false;
};
Blockly.utils.object.inherits(Blockly.Events.Ui, Blockly.Events.Abstract);

/**
 * Type of this event.
 * @type {string}
 */
Blockly.Events.Ui.prototype.type = Blockly.Events.UI;

/**
 * Encode the event as JSON.
 * @return {!Object} JSON representation.
 */
Blockly.Events.Ui.prototype.toJson = function() {
  var json = Blockly.Events.Ui.superClass_.toJson.call(this);
  json['element'] = this.element;
  if (this.newValue !== undefined) {
    json['newValue'] = this.newValue;
  }
  if (this.blockId) {
    json['blockId'] = this.blockId;
  }
  return json;
};

/**
 * Decode the JSON event.
 * @param {!Object} json JSON representation.
 */
Blockly.Events.Ui.prototype.fromJson = function(json) {
  Blockly.Events.Ui.superClass_.fromJson.call(this, json);
  this.element = json['element'];
  this.newValue = json['newValue'];
  this.blockId = json['blockId'];
};
