adapter.ts

import * as util from 'util';
import { window, OutputChannel, ViewColumn } from 'vscode';
import PromptFactory from '../prompts/factory';
import runAsync from '../utils/run-async';
const logger = require('yeoman-environment/lib/util/log');
const diff = require('diff');
const isFn = require('is-fn');

export default class CodeAdapter {

	public log = logger();
	private outChannel: OutputChannel;
	private outBuffer: string = '';

	constructor() {
		let self = this;

		this.outChannel = window.createOutputChannel('Yeoman');
		this.outChannel.clear();
		this.outChannel.show();

		// TODO Do not overwrite these methods
		console.error = console.log = function() {
			const line = util.format.apply(util, arguments);

			self.outBuffer += `${line}\n`;
			self.outChannel.appendLine(line);
			return this;
		};

		this.log.write = function() {
			const line = util.format.apply(util, arguments);

			self.outBuffer += line;
			self.outChannel.append(line);
			return this;
		};
	}

	public prompt(questions, callback) {
		let answers = {};
		callback = callback || function() {};

		const promise = questions.reduce((promise, question) => {
			return promise
				.then(() => {
					if (question.when === undefined) {
						return true;
					} else if (isFn(question.when)) {
						return runAsync(question.when)(answers);
					}

					return question.when;
				})
				.then(askQuestion => {
					if (askQuestion) {
						const prompt = PromptFactory.createPrompt(question, answers);

						return prompt.render().then(result => answers[question.name] = question.filter ? question.filter(result) : result);
					}
				});
		}, Promise.resolve());

		return promise
			.then(() => {
				this.outChannel.clear();
				this.outChannel.append(this.outBuffer);

				callback(answers);
				return answers;
			});
	}

	public diff(actual, expected) {
		this.outChannel.clear();

		let result = diff.diffLines(actual, expected);

		result.map(part => {
			let prefix = ' ';

			if (part.added === true) {
				prefix = '+';
			} else if (part.removed === true) {
				prefix = '-';
			}

			part.value = part.value.split('\n').map(line => {
				if (line.trim().length === 0) {
					return line;
				}

				return `${prefix}${line}`
			}).join('\n');

			this.outChannel.append(part.value);
		});
	}
}