/* eslint-disable camelcase */
const TerserPlugin = require('terser-webpack-plugin');
const CssMinimizerPlugin = require('css-minimizer-webpack-plugin');

const isProduction = process.env.NODE_ENV === 'production';

const optimization = {
  minimize: isProduction,
  minimizer: [
    new TerserPlugin({
      terserOptions: {
        parse: {
          // We want terser to parse ecma 8 code. However, we don't want it
          // to apply any minification steps that turns valid ecma 5 code
          // into invalid ecma 5 code. This is why the 'compress' and 'output'
          // sections only apply transformations that are ecma 5 safe
          // https://github.com/facebook/create-react-app/pull/4234
          ecma: 8,
        },
        compress: {
          ecma: 5,
          warnings: false,
          // Disabled because of an issue with Uglify breaking seemingly valid code:
          // https://github.com/facebook/create-react-app/issues/2376
          // Pending further investigation:
          // https://github.com/mishoo/UglifyJS2/issues/2011
          comparisons: false,
          // Disabled because of an issue with Terser breaking valid code:
          // https://github.com/facebook/create-react-app/issues/5250
          // Pending further investigation:
          // https://github.com/terser-js/terser/issues/120
          inline: 2,
        },
        mangle: {
          safari10: true,
        },
        // Added for profiling in devtools
        keep_classnames: isProduction,
        keep_fnames: isProduction,
        output: {
          ecma: 5,
          comments: false,
          // Turned on because emoji and regex is not minified properly using default
          // https://github.com/facebook/create-react-app/issues/2488
          ascii_only: true,
        },
      },
    }),
    new CssMinimizerPlugin(),
  ],
  runtimeChunk: {
    name: entrypoint => `runtime~${entrypoint.name}`,
  },
  splitChunks: {
    chunks: 'async',
    minSize: 20000,
    minRemainingSize: 0,
    minChunks: 1,
    maxAsyncRequests: 30,
    maxInitialRequests: 30,
    enforceSizeThreshold: 50000,
    cacheGroups: {
      defaultVendors: {
        test: /[\\/]node_modules[\\/]/,
        priority: -10,
        reuseExistingChunk: true,
      },
      default: {
        minChunks: 2,
        priority: -20,
        reuseExistingChunk: true,
      },
      reactVendors: {
        name: 'react-vendors',
        chunks: 'all',
        test: /[\\/]node_modules[\\/](react|react-dom|react-dom-router|@remix-run|scheduler)/,
        priority: 10,
        reuseExistingChunk: true,
      },
      lottieVendors: {
        name: 'lottie',
        chunks: 'all',
        test: /[\\/]node_modules[\\/](lottie)/,
        priority: 10,
        reuseExistingChunk: true,
      },
      antdVendors: {
        name: 'antd',
        chunks: 'all',
        test: /[\\/]node_modules[\\/](antd)/,
        priority: 10,
        reuseExistingChunk: true,
      },
      recharsVendors: {
        name: 'rechars',
        chunks: 'all',
        test: /[\\/]node_modules[\\/](recharts)/,
        priority: 10,
        reuseExistingChunk: true,
      },
      lodash: {
        name: 'lodash',
        chunks: 'all',
        test: /[\\/]node_modules[\\/](lodash)/,
        priority: 10,
        reuseExistingChunk: true,
      },
    },
  },
};

module.exports = optimization;