'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 semver = require('semver')
const paths = require('../config/paths')
const configFactory = require('../config/webpack.config')
const createDevServerConfig = require('../config/webpackDevServer.config')
const getClientEnvironment = require('../config/env')
const react = require(require.resolve('react', { paths: [paths.appPath] }))

const env = getClientEnvironment(paths.publicUrlOrPath.slice(0, -1))
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://cra.link/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, paths.publicUrlOrPath.slice(0, -1))
		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, paths.publicUrlOrPath)
		// 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()
			}

			if (env.raw.FAST_REFRESH && semver.lt(react.version, '16.10.0')) {
				console.log(chalk.yellow(`Fast Refresh requires React 16.10 or higher. You are using React ${react.version}.`))
			}

			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()
			})
		})

		if (process.env.CI !== 'true') {
			// Gracefully exit when stdin ends
			process.stdin.on('end', function () {
				devServer.close()
				process.exit()
			})
		}
	})
	.catch(err => {
		if (err && err.message) {
			console.log(err.message)
		}
		process.exit(1)
	})
