/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

import { Event } from '../../../../vs/base/common/event';
import { URI } from '../../../../vs/base/common/uri';
import {
  IMode,
  LanguageId,
  LanguageIdentifier,
} from '../../../../vs/editor/common/modes';
import { createDecorator } from '../../../../vs/platform/instantiation/common/instantiation';

export const IModeService = createDecorator<IModeService>('modeService');

export interface ILanguageExtensionPoint {
  id: string;
  extensions?: string[];
  filenames?: string[];
  filenamePatterns?: string[];
  firstLine?: string;
  aliases?: string[];
  mimetypes?: string[];
  configuration?: URI;
}

export interface ILanguageSelection {
  readonly languageIdentifier: LanguageIdentifier;
  readonly onDidChange: Event<LanguageIdentifier>;
}

export interface IModeService {
  readonly _serviceBrand: undefined;

  onDidCreateMode: Event<IMode>;

  // --- reading
  isRegisteredMode(mimetypeOrModeId: string): boolean;
  getModeIdForLanguageName(alias: string): string | null;
  getModeIdByFilepathOrFirstLine(
    resource: URI,
    firstLine?: string
  ): string | null;
  getModeId(commaSeparatedMimetypesOrCommaSeparatedIds: string): string | null;
  getLanguageIdentifier(modeId: string | LanguageId): LanguageIdentifier | null;

  // --- instantiation
  create(
    commaSeparatedMimetypesOrCommaSeparatedIds: string | undefined
  ): ILanguageSelection;
  createByFilepathOrFirstLine(
    resource: URI | null,
    firstLine?: string
  ): ILanguageSelection;

  triggerMode(commaSeparatedMimetypesOrCommaSeparatedIds: string): void;
}