// Copyright (c) Microsoft Corporation. All rights reserved.

// Licensed under the MIT License.

'use strict';

import { inject, injectable, named } from 'inversify';

import { Memento } from 'vscode';

import { getExperimentationService, IExperimentationService, TargetPopulation } from 'vscode-tas-client';

import { sendTelemetryEvent } from '../../telemetry';

import { EventName } from '../../telemetry/constants';

import { IApplicationEnvironment } from '../application/types';

import { GLOBAL_MEMENTO, IConfigurationService, IExperimentService, IMemento, IPythonSettings } from '../types';

import { ExperimentationTelemetry } from './telemetry';

@injectable()

export class ExperimentService implements IExperimentService {

/**

* Experiments the user requested to opt into manually.

*/

public _optInto: string[] = [];

/**

* Experiments the user requested to opt out from manually.

*/

public _optOutFrom: string[] = [];

private readonly experimentationService?: IExperimentationService;

private readonly settings: IPythonSettings;

constructor(

@inject(IConfigurationService) readonly configurationService: IConfigurationService,

@inject(IApplicationEnvironment) private readonly appEnvironment: IApplicationEnvironment,

@inject(IMemento) @named(GLOBAL_MEMENTO) readonly globalState: Memento

) {

this.settings = configurationService.getSettings(undefined);

// Users can only opt in or out of experiment groups, not control groups.

const optInto = this.settings.experiments.optInto;

const optOutFrom = this.settings.experiments.optOutFrom;

this._optInto = optInto.filter((exp) => !exp.endsWith('control'));

this._optOutFrom = optOutFrom.filter((exp) => !exp.endsWith('control'));

// Don't initialize the experiment service if the extension's experiments setting is disabled.

const enabled = this.settings.experiments.enabled;

if (!enabled) {

return;

}

let targetPopulation: TargetPopulation;

if (this.appEnvironment.channel === 'insiders') {

targetPopulation = TargetPopulation.Insiders;

} else {

targetPopulation = TargetPopulation.Public;

}

const telemetryReporter = new ExperimentationTelemetry();

this.experimentationService = getExperimentationService(

this.appEnvironment.extensionName,

this.appEnvironment.packageJson.version!,

targetPopulation,

telemetryReporter,

globalState

);

}

public async inExperiment(experiment: string): Promise<boolean> {

if (!this.experimentationService) {

return false;

}

// Currently the service doesn't support opting in and out of experiments,

// so we need to perform these checks and send the corresponding telemetry manually.

if (this._optOutFrom.includes('All') || this._optOutFrom.includes(experiment)) {

sendTelemetryEvent(EventName.PYTHON_EXPERIMENTS_OPT_IN_OUT, undefined, {

expNameOptedOutOf: experiment

});

return false;

}

if (this._optInto.includes('All') || this._optInto.includes(experiment)) {

sendTelemetryEvent(EventName.PYTHON_EXPERIMENTS_OPT_IN_OUT, undefined, {

expNameOptedInto: experiment

});

return true;

}

return this.experimentationService.isCachedFlightEnabled(experiment);

}

}