'use strict';

const path = require('path');
const webpack = require('webpack');
const TerserPlugin = require('terser-webpack-plugin');
const CopyPlugin = require('copy-webpack-plugin');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');

process.env.BABEL_ENV = process.env.NODE_ENV;
const isDev = process.env.NODE_ENV !== 'production';

const resolveDir = dir => path.resolve(__dirname, dir);
const HTMLPlugin = require('html-webpack-plugin');
const html = new HTMLPlugin({
  title: 'yacd - Yet Another Clash Dashboard',
  template: 'src/index.template.ejs',
  inject: false,
  filename: 'index.html'
});

const svgSpriteRule = {
  test: /\.svg$/,
  use: ['svg-sprite-loader']
};

// ---- entry

const entry = {
  app: ['react-hot-loader/patch', './src/app.js']
};

// ---- output

const output = {
  path: path.resolve(__dirname, 'public'),
  // use contenthash instead of chunkhash to take advantage of caching
  filename: isDev ? '[name].bundle.js' : '[name].[contenthash].js',
  publicPath: ''
};

// const vendor = ['redux', 'react', 'react-dom', 'react-router-dom'];

// if (!isDev) entry.vendor = vendor; // generate common vendor bundle in prod

// if (isDev) {
//   const dllRefPlugin = new webpack.DllReferencePlugin({
//     context: '.',
//     manifest: require('./public/vendor-manifest.json')
//   });
//   plugins.push(dllRefPlugin);
// }

// since we don't use dll plugin for now - we still get vendor's bundled in a separate bundle
// entry.vendor = vendor;
// entry.react = react;

const mode = isDev ? 'development' : 'production';

const definePlugin = new webpack.DefinePlugin({
  __DEV__: JSON.stringify(isDev),
  'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV)
});

// https://webpack.js.org/configuration/devtool/
let devtool;
if (isDev) {
  devtool = 'eval-source-map';
} else {
  // devtool = 'source-map';
  devtool = false;
}

const loaders = {
  style: {
    loader: 'style-loader',
    options: {
      // workaround css modules HMR issue
      // see https://github.com/webpack-contrib/style-loader/issues/320
      hmr: false
    }
  },
  css: { loader: 'css-loader' },
  cssModule: {
    loader: 'css-loader',
    options: {
      modules: true,
      localIdentName: isDev
        ? '[path]_[name]_[local]_[hash:base64:5]'
        : '[hash:base64:10]'
    }
  },
  postcss: {
    loader: 'postcss-loader',
    options: {
      plugins: () =>
        [
          require('postcss-import')(),
          require('postcss-nested')(),
          require('autoprefixer')(),
          require('postcss-extend-rule')(),
          isDev ? false : require('cssnano')()
        ].filter(Boolean)
    }
  }
};

const rulesCss = {
  test: /\.css$/,
  exclude: /\.module\.css$/,
  use: [
    isDev ? loaders.style : MiniCssExtractPlugin.loader,
    loaders.css,
    loaders.postcss
  ].filter(Boolean)
};

const rulesCssModules = {
  test: /\.module\.css$/,
  use: [
    isDev ? loaders.style : MiniCssExtractPlugin.loader,
    loaders.cssModule,
    loaders.postcss
  ].filter(Boolean)
};

const cssExtractPlugin = new MiniCssExtractPlugin({
  filename: isDev ? '[name].bundle.css' : '[name].[chunkhash].css'
});

const { BundleAnalyzerPlugin } = require('webpack-bundle-analyzer');
const bundleAnalyzerPlugin = new BundleAnalyzerPlugin({
  analyzerMode: 'static',
  reportFilename: 'report.html',
  openAnalyzer: false
});

const plugins = [
  // in webpack 4 namedModules will be enabled by default
  html,
  definePlugin,
  new CopyPlugin([{ from: 'assets/*', flatten: true }]),
  new CleanWebpackPlugin(),
  isDev ? false : new webpack.HashedModuleIdsPlugin(),
  isDev ? false : cssExtractPlugin,
  isDev ? false : bundleAnalyzerPlugin
].filter(Boolean);

module.exports = {
  devtool,
  entry,
  output,
  mode,
  resolve: {
    alias: {
      'react-dom': '@hot-loader/react-dom',
      a: resolveDir('src/api'),
      s: resolveDir('src/svg'),
      m: resolveDir('src/misc'),
      d: resolveDir('src/ducks'),
      c: resolveDir('src/components')
    }
  },
  module: {
    rules: [
      svgSpriteRule,
      // js loader
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: ['babel-loader']
      },
      // file loader
      {
        test: /\.(ttf|eot|woff|woff2)(\?.+)?$/,
        use: [
          {
            loader: 'file-loader',
            options: {
              name: '[name].[ext]'
            }
          }
        ]
      },
      rulesCss,
      rulesCssModules
    ]
  },
  optimization: {
    splitChunks: {
      chunks: 'all',
      // see https://gist.github.com/sokra/1522d586b8e5c0f5072d7565c2bee693#optimizationruntimechunk
      cacheGroups: {
        // corejs: {
        //   test: /[\\/]node_modules[\\/](core-js)[\\/]/,
        //   chunks: 'all'
        // },
        // chartjs: {
        //   test: /[\\/]node_modules[\\/]chart\.js[\\/]/,
        //   // name: 'chartjs',
        //   chunks: 'all'
        // },
        react: {
          test: /[\\/]node_modules[\\/](react-dom|react|redux|react-router|react-router-dom|schedule|react-redux|react-modal)[\\/]/,
          chunks: 'all'
        }
      }
    },
    runtimeChunk: true,
    minimizer: [
      // the current uglifyjs-webpack-plugin has problems workin with React Hooks
      // see also:
      // https://github.com/webpack-contrib/uglifyjs-webpack-plugin/issues/374
      new TerserPlugin({
        cache: true,
        parallel: true
      })
    ]
  },
  plugins
};