const path = require('path')
const webpack = require('webpack')
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const CompressionPlugin = require('compression-webpack-plugin')
const Dotenv = require('dotenv-webpack')
const srcDir = path.resolve(__dirname, '..', 'scss')
const distDir = path.resolve(__dirname, '..', 'dist')
const { NODE_ENV = 'development' } = process.env

module.exports = {
  // Where to fine the source code
  context: srcDir,
  // No source map for production build
  devtool: 'cheap-module-source-map',
  entry: ['./index.js'],
  output: {
    // The destination file name concatenated with hash (generated whenever you change your code).
    // The hash is really useful to let the browser knows when it should get a new bundle
    // or use the one in cache
    filename: 'main.js',
    // The destination folder where to put the output bundle
    path: distDir,
    // Wherever resource (css, js, img) you call <script src="..."></script>,
    // or css, or img use this path as the root
    publicPath: '/',
    // At some point you'll have to debug your code, that's why I'm giving you
    // for free a source map file to make your life easier
    sourceMapFilename: 'main.map'
  },

  module: {
    rules: [
      {
        // Webpack, when walking down the tree, whenever you see `.js` file use babel to transpile
        // the code to ES5. I don't want you to look into the node_modules folder.
        test: /\.js$/,
        exclude: /node_modules/,
        use: ['babel-loader'],
        include: srcDir
      },
      {
        test: /\.scss$/,
        exclude: /node_modules/,
        use: ExtractTextPlugin.extract({
          fallback: 'style-loader',
          use: [
            {
              loader: 'css-loader',
              options: {
                minimize: true,
                sourceMap: true
              }
            },
            { loader: 'sass-loader' }
          ]
        })
      },
      {
        test: /\.hbs$/,
        loader: 'handlebars-loader',
        query: {
          partialDirs: [path.join(srcDir, 'templates', 'partials')],
          helperDirs: [path.join(srcDir, 'templates', 'helpers')]
        }
      },
      {
        test: /\.(eot?.+|svg?.+|ttf?.+|otf?.+|ico?.+|zip?.+|woff?.+|woff2?.+)$/,
        use: 'file-loader?name=[path][name].[ext]'
      },
      {
        test: /\.(jpg|jpeg|png|gif|ico)$/,
        use: [
          // if less than 10Kb, bundle the asset inline, if greater, copy it to the dist/assets
          // folder using file-loader
          'url-loader?limit=1024&name=[path][name].[ext]'
        ],
        include: path.resolve(srcDir, 'assets')
      }
    ]
  },

  plugins: [
    new webpack.optimize.ModuleConcatenationPlugin(),
    new webpack.HashedModuleIdsPlugin(),
    // environment globals added must be added to .eslintrc
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: JSON.stringify(NODE_ENV)
      },
      NODE_ENV: NODE_ENV,
      __DEV__: NODE_ENV === 'development',
      __PROD__: NODE_ENV === 'production'
    }),
    new webpack.optimize.UglifyJsPlugin({
      compress: {
        warnings: false,
        screw_ie8: true,
        conditionals: true,
        unused: true,
        comparisons: true,
        sequences: true,
        dead_code: true,
        evaluate: true,
        if_return: true,
        join_vars: true
      },
      output: {
        comments: false
      }
    }),
    // Put all css code in this file
    new ExtractTextPlugin({
      filename: '[name].css',
      allChunks: true
    }),
    new CompressionPlugin({
      asset: '[path].gz[query]',
      algorithm: 'gzip',
      test: /\.js$|\.css$|\.html$|\.eot?.+$|\.ttf?.+$|\.woff?.+$|\.svg?.+$/,
      threshold: 10240 // Only assets bigger than this size are processed
    }),
    new webpack.ProvidePlugin({
      $: 'jquery',
      jQuery: 'jquery',
      'window.jQuery': 'jquery'
    }),
    new Dotenv({
      path: path.resolve(__dirname, '..', '.env'),
      safe: false
    })
  ]
}