// Copyright (c) Jupyter Development Team.
// Distributed under the terms of the Modified BSD License.

import { Token } from '@lumino/coreutils';

import { WidgetModel, WidgetView } from './widget';

/**
 * A runtime interface token for a widget registry.
 */
export const IJupyterWidgetRegistry = new Token<IJupyterWidgetRegistry>(
  'jupyter.extensions.jupyterWidgetRegistry'
);

/**
 * A registry of Jupyter Widgets.
 *
 * This is used by widget managers that support an external registry.
 */
export interface IJupyterWidgetRegistry {
  /**
   * Register a widget module.
   */
  registerWidget(data: IWidgetRegistryData): void;
}

export type ExportMap = {
  [key: string]: typeof WidgetModel | typeof WidgetView;
};

export type ExportData =
  | ExportMap
  | Promise<ExportMap>
  | (() => ExportMap)
  | (() => Promise<ExportMap>);

export interface IWidgetRegistryData {
  /**
   * The widget module name.
   */
  name: string;

  /**
   * The widget module version.
   */
  version: string;

  /**
   * A map of object names to widget classes provided by the module, or a
   * promise to such a map, or a function returning the same.
   */
  exports: ExportData;
}