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

// Licensed under the MIT License.

'use strict';

import { inject, injectable } from 'inversify';

import { IFileSystem } from '../common/platform/types';

import { IProcessServiceFactory } from '../common/process/types';

import { IServiceContainer } from '../ioc/types';

import { IExcutableValidator } from './types';

@injectable()

export class ExcutableValidator implements IExcutableValidator {

constructor(@inject(IServiceContainer) private readonly serviceContainer: IServiceContainer) { }

/**

* Checks the validity of the executable.

* Do not use `<python> --version` as the output in 2.7 comes in stderr.

* Check if either one of the following is true:

* 1. Use `<python> -c print('1')` as the executable could python.

* 2. Check if the executable file exists (in case of `spark-submit`)

* @param {string} exePath

* @returns {Promise<boolean>}

* @memberof DebuggerExcutableValidator

*/

public async validateExecutable(exePath: string): Promise<boolean> {

const processFactory = this.serviceContainer.get<IProcessServiceFactory>(IProcessServiceFactory);

const fs = this.serviceContainer.get<IFileSystem>(IFileSystem);

const processService = await processFactory.create();

const [valid, execuableExists] = await Promise.all([

processService.exec(exePath, ['-c', 'print("1")'])

.then(output => output.stdout.trim() === '1')

.catch(() => false),

fs.fileExists(exePath)

]);

return valid || execuableExists;

}

}