Files
blockly/core/events/events_comment_drag.ts
Christopher Allen 7ccdcc5cef refactor(events): introduce EventType enum in separate module (#8530)
* refactor(events): Use "export ... from" where applicable

* refactor(events): Introduce EventType enum

  Introduce an enum for the event .type values.  We can't actually
  use it as the type of the .type property on Abstract events,
  because we want to allow developers to add their own custom
  event types inheriting from this type, but at least this way we
  can be reasonably sure that all of our own event subclasses have
  distinct .type values—plus consistent use of enum syntax
  (EventType.TYPE_NAME) is probably good for readability overall.

  Put it in a separate module from the rest of events/utils.ts
  because it would be helpful if event utils could use

      event instanceof SomeEventType

  for type narrowing but but at the moment most events are in
  modules that depend on events/utils.ts for their .type
  constant, and although circular ESM dependencies should work
  in principle there are various restrictions and this
  particular circularity causes issues at the moment.

  A few of the event classes also depend on utils.ts for fire()
  or other functions, which will be harder to deal with, but at
  least this commit is win in terms of reducing the complexity
  of our dependencies, making most of the Abstract event subclass
  module dependent on type.ts, which has no imports, rather than
  on utils.ts which has multiple imports.
2024-08-20 08:36:33 +01:00

100 lines
2.8 KiB
TypeScript

/**
* @license
* Copyright 2024 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
/**
* Events fired when a workspace comment is dragged.
*/
import type {WorkspaceComment} from '../comments/workspace_comment.js';
import * as registry from '../registry.js';
import {Workspace} from '../workspace.js';
import {AbstractEventJson} from './events_abstract.js';
import {UiBase} from './events_ui_base.js';
import {EventType} from './type.js';
/**
* Notifies listeners when a comment is being manually dragged/dropped.
*/
export class CommentDrag extends UiBase {
/** The ID of the top-level comment being dragged. */
commentId?: string;
/** True if this is the start of a drag, false if this is the end of one. */
isStart?: boolean;
override type = EventType.COMMENT_DRAG;
/**
* @param opt_comment The comment that is being dragged.
* Undefined for a blank event.
* @param opt_isStart Whether this is the start of a comment drag.
* Undefined for a blank event.
*/
constructor(opt_comment?: WorkspaceComment, opt_isStart?: boolean) {
const workspaceId = opt_comment ? opt_comment.workspace.id : undefined;
super(workspaceId);
if (!opt_comment) return;
this.commentId = opt_comment.id;
this.isStart = opt_isStart;
}
/**
* Encode the event as JSON.
*
* @returns JSON representation.
*/
override toJson(): CommentDragJson {
const json = super.toJson() as CommentDragJson;
if (this.isStart === undefined) {
throw new Error(
'Whether this event is the start of a drag is undefined. ' +
'Either pass the value to the constructor, or call fromJson',
);
}
if (this.commentId === undefined) {
throw new Error(
'The comment ID is undefined. Either pass a comment to ' +
'the constructor, or call fromJson',
);
}
json['isStart'] = this.isStart;
json['commentId'] = this.commentId;
return json;
}
/**
* Deserializes the JSON event.
*
* @param event The event to append new properties to. Should be a subclass
* of CommentDrag, but we can't specify that due to the fact that parameters
* to static methods in subclasses must be supertypes of parameters to
* static methods in superclasses.
* @internal
*/
static fromJson(
json: CommentDragJson,
workspace: Workspace,
event?: any,
): CommentDrag {
const newEvent = super.fromJson(
json,
workspace,
event ?? new CommentDrag(),
) as CommentDrag;
newEvent.isStart = json['isStart'];
newEvent.commentId = json['commentId'];
return newEvent;
}
}
export interface CommentDragJson extends AbstractEventJson {
isStart: boolean;
commentId: string;
}
registry.register(registry.Type.EVENT, EventType.COMMENT_DRAG, CommentDrag);