'use strict';

import {

CancellationToken, DefinitionParams,

DefinitionRequest, Location,

LocationLink

} from 'vscode-languageclient';

import { LanguageClient } from 'vscode-languageclient/node';

import { getActiveLanguageClient } from './extension';

type GoToDefinitionResponse = Location | Location[] | LocationLink[] | null;

export type GoToDefinitionCommand = (params: DefinitionParams, token?: CancellationToken) => Promise<GoToDefinitionResponse>;

export function goToDefinitionProvider(): GoToDefinitionCommand {

return async (params: DefinitionParams, token?: CancellationToken): Promise<GoToDefinitionResponse> => {

const languageClient: LanguageClient | undefined = await getActiveLanguageClient();

if (!languageClient) {

return null;

}

if (token !== undefined) {

return languageClient.sendRequest(DefinitionRequest.type, params, token);

}

return languageClient.sendRequest(DefinitionRequest.type, params);

};

}