const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const TerserPlugin = require('terser-webpack-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');

const env = process.env.NODE_ENV;
const publicPath = process.env.PUBLIC_PATH ? `${process.env.PUBLIC_PATH}/` : process.env.PUBLIC_PATH;

if (!['development', 'production'].includes(env)) {
  throw new Error('Invalid NODE_ENV');
}

if (!process.env.LIB_NAME) {
  throw new Error('Invalid LIB_NAME');
}

module.exports = {
  mode: env,
  devtool: 'source-map',
  entry: path.resolve(__dirname, `./src/${process.env.LIB_NAME}/index.js`),
  module: {
    rules: [
      {
        test: /\.js$/i,
        loader: 'babel-loader',
        exclude: [/node_modules/],
        options: {
          presets: [
            [
              '@babel/preset-env',
              {
                useBuiltIns: 'usage',
              },
            ],
          ],
        },
      },
      {
        test: /\.css$/i,
        use: ['style-loader', 'css-loader?sourceMap'],
      },
      {
        test: /\.(svg|png|jpe?g|gif)$/i,
        use: [
          {
            loader: 'file-loader',
            options: {},
          },
        ],
      },
      {
        test: /\.(ttf|eot|woff|woff2)$/i,
        use: {
          loader: 'file-loader',
          options: {
            name: 'fonts/[name].[ext]',
          },
        },
      },
      {
        test: /\.html$/,
        exclude: /node_modules/,
        use: [
          {
            loader: 'html-loader',
            options: {
              ignoreCustomFragments: [/\{\{.*?}}/],
              root: path.resolve(__dirname, 'src'),
              attrs: ['img:src', 'link:href'],
            },
          },
        ],
      },
    ],
  },
  output: {
    chunkFilename: '[id].[contenthash:8].js',
    path: path.resolve(__dirname, `./dist-${process.env.LIB_NAME}`),
    publicPath,
    library: 'MobileStories',
  },
  plugins: [
    new HtmlWebpackPlugin({
      minify: {
        removeComments: true,
        sortAttributes: true,
        keepClosingSlash: true,
        collapseWhitespace: true,
      },
      filename: 'index.html',
      template: path.resolve(__dirname, `./src/${process.env.LIB_NAME}/index.html`),
    }),
  ],
  optimization: {
    minimizer: [new TerserPlugin(), new OptimizeCSSAssetsPlugin({})],
  },
};