/* eslint-disable no-console */

// 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('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 { checkBrowsers } = require('react-dev-utils/browsersHelper');
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 = 3000;
const PORT = parseInt(process.env.PORT) || DEFAULT_PORT;
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('http://bit.ly/CRA-advanced-config')}`
  );
  console.log();
}

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.
    choosePort(HOST, 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 urls = prepareUrls(protocol, HOST, port);

    // Create a webpack compiler that is configured with custom messages.
    const compiler = createCompiler(webpack, config, appName, urls, useYarn);

    // 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();
      }

      console.log(chalk.cyan('Starting the development server...\n'));

      return openBrowser(urls.localUrlForBrowser);
    });

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

    process.exit(1);
  });