'use strict';

// Do this as the first thing so that any code reading it knows the right env.
process.env.BABEL_ENV = 'development';
process.env.NODE_ENV = 'development';

// Makes the script crash on unhandled rejections instead of silently
// ignoring them. In the future, promise rejections that are not handled will
// terminate the Node.js process with a non-zero exit code.
process.on('unhandledRejection', (err) => {
	throw err;
});

// Ensure environment variables are read.
require('../config/env');


const fs = require('fs');
const chalk = require('react-dev-utils/chalk');
const webpack = require('webpack');
const WebpackDevServer = require('webpack-dev-server');
const clearConsole = require('react-dev-utils/clearConsole');
const checkRequiredFiles = require('react-dev-utils/checkRequiredFiles');
const {
	choosePort,
	createCompiler,
	prepareProxy,
	prepareUrls,
} = require('react-dev-utils/WebpackDevServerUtils');
const openBrowser = require('react-dev-utils/openBrowser');
const paths = require('../config/paths');
const configFactory = require('../config/webpack.config');
const createDevServerConfig = require('../config/webpackDevServer.config');

const useYarn = fs.existsSync(paths.yarnLockFile);
const isInteractive = process.stdout.isTTY;

// Warn and crash if required files are missing
if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
	process.exit(1);
}

// Tools like Cloud9 rely on this.
const DEFAULT_PORT = parseInt(process.env.PORT, 10) || 3000;
const HOST = process.env.HOST || '0.0.0.0';

if (process.env.HOST) {
	console.log(
		chalk.cyan(
			`Attempting to bind to HOST environment variable: ${chalk.yellow(
				chalk.bold(process.env.HOST)
			)}`
		)
	);
	console.log(
		'If this was unintentional, check that you haven\'t mistakenly set it in your shell.'
	);
	console.log(
		`Learn more here: ${chalk.yellow('https://bit.ly/CRA-advanced-config')}`
	);
	console.log();
}

// We require that you explicitly set browsers and do not fall back to
// browserslist defaults.
const { checkBrowsers } = require('react-dev-utils/browsersHelper');
checkBrowsers(paths.appPath, isInteractive)
	.then(() => {
		// We attempt to use the default port but if it is busy, we offer the user to
		// run on a different port. `choosePort()` Promise resolves to the next free port.
		return choosePort(HOST, DEFAULT_PORT);
	})
	.then((port) => {
		if (port == null) {
			// We have not found a port.
			return;
		}
		const config = configFactory('development');
		const protocol = process.env.HTTPS === 'true' ? 'https' : 'http';
		const appName = require(paths.appPackageJson).name;
		const useTypeScript = fs.existsSync(paths.appTsConfig);
		const tscCompileOnError = process.env.TSC_COMPILE_ON_ERROR === 'true';
		const urls = prepareUrls(protocol, HOST, port);
		const devSocket = {
			warnings: (warnings) =>
				devServer.sockWrite(devServer.sockets, 'warnings', warnings),
			errors: (errors) =>
				devServer.sockWrite(devServer.sockets, 'errors', errors),
		};
		// Create a webpack compiler that is configured with custom messages.
		const compiler = createCompiler({
			appName,
			config,
			devSocket,
			urls,
			useYarn,
			useTypeScript,
			tscCompileOnError,
			webpack,
		});
		// Load proxy config
		const proxySetting = require(paths.appPackageJson).proxy;
		const proxyConfig = prepareProxy(proxySetting, paths.appPublic);
		// Serve webpack assets generated by the compiler over a web server.
		const serverConfig = createDevServerConfig(
			proxyConfig,
			urls.lanUrlForConfig
		);
		const devServer = new WebpackDevServer(compiler, serverConfig);
		// Launch WebpackDevServer.
		devServer.listen(port, HOST, (err) => {
			if (err) {
				return console.log(err);
			}
			if (isInteractive) {
				clearConsole();
			}

			// We used to support resolving modules according to `NODE_PATH`.
			// This now has been deprecated in favor of jsconfig/tsconfig.json
			// This lets you use absolute paths in imports inside large monorepos:
			if (process.env.NODE_PATH) {
				console.log(
					chalk.yellow(
						'Setting NODE_PATH to resolve modules absolutely has been deprecated in favor of setting baseUrl in jsconfig.json (or tsconfig.json if you are using TypeScript) and will be removed in a future major release of create-react-app.'
					)
				);
				console.log();
			}

			console.log(chalk.cyan('Starting the development server...\n'));
			openBrowser(urls.localUrlForBrowser);
		});

		['SIGINT', 'SIGTERM'].forEach(function(sig) {
			process.on(sig, function() {
				devServer.close();
				process.exit();
			});
		});
	})
	.catch((err) => {
		if (err && err.message) {
			console.log(err.message);
		}
		process.exit(1);
	});