// Dependencies
const {
  dest,
  src
} = require('gulp');
const uglify = require('gulp-uglify-es').default;
const concat = require('gulp-concat');
const webpack = require('webpack-stream');
const config = require('../config.js');

// Task
function js(cb) {
  return src(config.js.main)
    .pipe(
      webpack({
        externals: {
          jquery: 'jQuery' // Available and loaded through WordPress.
        },
        mode: 'production',
        module: {
          rules: [{
            test: /.js$/,
            use: [{
              loader: 'babel-loader'
            }]
          }]
        },
        output: {
          filename: 'all.js'
        }
      })
    )
    .pipe(concat('all.js'))
    .pipe(
      uglify(config.js.uglify.opts).on('error', function (err) {
        util.log(util.colors.red('[Error]'), err.toString());
        this.emit('end');
      }),
    )
    .pipe(dest(config.js.dest));
  cb();
}

exports.js = js;