const CopyPlugin = require('copy-webpack-plugin');
const webpack = require('webpack');
const fs = require('fs');
const path = require('path');

// Load developer-local overrides (gitignored) so `npm run build` picks up
// TINODE_API_KEY etc. without having to export them by hand every time.
const envLocalPath = path.resolve(__dirname, '.env.local');
if (fs.existsSync(envLocalPath)) {
  for (const line of fs.readFileSync(envLocalPath, 'utf8').split('\n')) {
    const match = line.match(/^\s*([A-Z_][A-Z0-9_]*)\s*=\s*(.*)\s*$/);
    if (match) {
      process.env[match[1]] = process.env[match[1]] || match[2];
    }
  }
}

module.exports = (env, argv) => {
  const mode = argv.mode === 'production' ? 'prod' : 'dev';
  const maxAssetSize = mode === 'prod' ? 360000 : 1512000;
  return {
    entry: {
      index: path.resolve(__dirname, 'src/index.js'),
    },
    devtool: 'source-map',
    module: {
      rules: [
        {
          test: /\.jsx?$/,
          use: [
            {
              loader: 'babel-loader',
              options: {
                envName: mode === 'prod' ? 'production' : 'development',
              },
            },
          ],
          exclude: /node_modules/,
        },
      ],
    },
    output: {
      path: path.resolve(__dirname, 'umd'),
      filename: `[name].${mode}.js`,
      publicPath: '/umd/'
    },
    optimization: {
      minimize: (mode === 'prod'),
      minimizer: ['...']
    },
    performance: {
      maxEntrypointSize: maxAssetSize,
      maxAssetSize: maxAssetSize,
      assetFilter: function(assetFilename) {
        // Exclude all sourcemaps
        if (/\.map$/.test(assetFilename)) {
          return false;
        }
        return true;
      },
    },
    plugins: [
      new CopyPlugin({
        patterns: [
          { from: `node_modules/tinode-sdk/umd/tinode.${mode}.js`, to: `tinode.${mode}.js` },
          { from: `node_modules/tinode-sdk/umd/tinode.${mode}.js.map`, to: `tinode.${mode}.js.map` },
        ],
      }),
      // Bakes TINODE_API_KEY (from the environment or .env.local) into the bundle at build
      // time. See src/config.js for the fallback used when it's not set.
      new webpack.DefinePlugin({
        'process.env.TINODE_API_KEY': JSON.stringify(process.env.TINODE_API_KEY || ''),
      }),
    ],
    externals: {
      'livekit-client': 'LivekitClient',
      'qrcodejs': 'QRCode',
      'react': 'React',
      'react-dom': 'ReactDOM',
      'react-intl': 'ReactIntl',
      'tinode-sdk': 'tinode',
    },
  };
}