text: const path = require('path');
  const webpack = require('webpack')
  const ExtractTextPlugin = require('extract-text-webpack-plugin')
  
  process.env.NODE_ENV = process.env.NODE_ENV || 'development'
  if (process.env.NODE_ENV === 'test') {
    require('dotenv').config({path:'.env.test'})
  } else if (process.env.NODE_ENV === 'development' ) {
    require('dotenv').config({path:'.env.development'})
  }
  
  module.exports =(env)=>{
    const isProduction = env ==='production'
    const CSSExtract = new ExtractTextPlugin('styles.css')
  
    return {
      entry: ['babel-polyfill','./src/app.js'],
      output: {
        path: path.join(__dirname, 'public', 'dist'),
        filename: 'bundle.js'
      },
      module: {
        rules: [{
          loader: 'babel-loader',
          test: /\.js$/,
          exclude: /node_modules/
        }, {
          test: /\.s?css$/,
          use: CSSExtract.extract({
            use:[
              {
                loader:'css-loader',
                options:{
                  sourceMap:true
                }
              },
              {
                loader:'sass-loader',
                options:{
                  sourceMap:true
                }
              }
            ]
          })
        }]
      },
      plugins:[
        CSSExtract,
        new webpack.DefinePlugin({
          'process.env.FIREBASE_API_KEY': JSON.stringify(process.env.FIREBASE_API_KEY),
          'process.env.FIREBASE_AUTH_DOMAIN': JSON.stringify(process.env.FIREBASE_AUTH_DOMAIN),
          'process.env.FIREBASE_DATABASE_URL': JSON.stringify(process.env.FIREBASE_DATABASE_URL),
          'process.env.FIREBASE_PROJECT_ID': JSON.stringify(process.env.FIREBASE_PROJECT_ID),
          'process.env.FIREBASE_STORAGE_BUCKET': JSON.stringify(process.env.FIREBASE_STORAGE_BUCKET),
          'process.env.FIREBASE_MESSAGING_ID': JSON.stringify(process.env.FIREBASE_MESSAGING_ID)
        })
      ],
      devtool: isProduction ? 'source-map' : 'inline-source-map',
      devServer: {
        contentBase: path.join(__dirname, 'public'),
        historyApiFallback: true,
        publicPath: '/dist/'
      }
    };
  
  }
  