const webpack = require('webpack'); // webpack engine
const webpackConfig = require('./webpack.config.js'); // webpack configuration object
const WebpackDevServer = require('webpack-dev-server'); // webpack development server

// Set the event based on the npm script that is running (start, build, test, etc.)
const npmEvent = process.env.npm_lifecycle_event;

// decide which method to run based on the event
switch (npmEvent) {
  ...
}

// method to create and run development server
function startDevelopmentServer() {
  const compiler = webpack(webpackConfig);
  const server = new WebpackDevServer(compiler, {
    hot: true,
    stats: 'minimal'
  });

  server.listen('8080', 'localhost', () => console.log(`WebpackDevServer running on port 8080`));
}

// method to build static webapp
function buildDistFolder() {
  const compiler = webpack(webpackConfig);

  compiler.run((err, stats) => {
    if (err || stats.hasErrors()) {
      console.info(err);
    }
    console.info('dist build finished');
  });
}