const path = require('path');

module.exports = {

  // click on the name of the option to get to the detailed documentation

  // click on the items with arrows to show more examples / advanced options

  entry: "./app/entry", // string | object | array

  // Here the application starts executing

  // and webpack starts bundling

  output: {

    // options related to how webpack emits results

    path: path.resolve(__dirname, "dist"), // string

    // the target directory for all output files

    // must be an absolute path (use the Node.js path module)

    filename: "bundle.js", // string

    // the filename template for entry chunks

    publicPath: "/assets/", // string

    // the url to the output directory resolved relative to the HTML page

    library: "MyLibrary", // string,

    // the name of the exported library

    libraryTarget: "umd", // universal module definition

    // the type of the exported library

    /* Advanced output configuration (click to show) */

  },

  module: {

    // configuration regarding modules

    rules: [

      // rules for modules (configure loaders, parser options, etc.)

      {

        test: /\.jsx?$/,

        include: [

          path.resolve(__dirname, "app")

        ],

        exclude: [

          path.resolve(__dirname, "app/demo-files")

        ],

        // these are matching conditions, each accepting a regular expression or string

        // test and include have the same behavior, both must be matched

        // exclude must not be matched (takes preferrence over test and include)

        // Best practices:

        // - Use RegExp only in test and for filename matching

        // - Use arrays of absolute paths in include and exclude

        // - Try to avoid exclude and prefer include

        issuer: { test, include, exclude },

        // conditions for the issuer (the origin of the import)

        enforce: "pre",

        enforce: "post",

        // flags to apply these rules, even if they are overridden (advanced option)

        loader: "babel-loader",

        // the loader which should be applied, it'll be resolved relative to the context

        // -loader suffix is no longer optional in webpack2 for clarity reasons

        // see webpack 1 upgrade guide

        options: {

          presets: ["es2015"]

        },

        // options for the loader

      },

      {

        test: "\.html$",

        use: [

          // apply multiple loaders and options

          "htmllint-loader",

          {

            loader: "html-loader",

            options: {

              /* ... */

            }

          }

        ]

      },

      { oneOf: [ /* rules */ ] },

      // only use one of these nested rules

      { rules: [ /* rules */ ] },

      // use all of these nested rules (combine with conditions to be useful)

      { resource: { and: [ /* conditions */ ] } },

      // matches only if all conditions are matched

      { resource: { or: [ /* conditions */ ] } },

      { resource: [ /* conditions */ ] },

      // matches if any condition is matched (default for arrays)

      { resource: { not: /* condition */ } }

      // matches if the condition is not matched

    ],

    /* Advanced module configuration (click to show) */

  },

  resolve: {

    // options for resolving module requests

    // (does not apply to resolving to loaders)

    modules: [

      "node_modules",

      path.resolve(__dirname, "app")

    ],

    // directories where to look for modules

    extensions: [".js", ".json", ".jsx", ".css"],

    // extensions that are used

    alias: {

      // a list of module name aliases

      "module": "new-module",

      // alias "module" -> "new-module" and "module/path/file" -> "new-module/path/file"

      "only-module$": "new-module",

      // alias "only-module" -> "new-module", but not "module/path/file" -> "new-module/path/file"

      "module": path.resolve(__dirname, "app/third/module.js"),

      // alias "module" -> "./app/third/module.js" and "module/file" results in error

      // modules aliases are imported relative to the current context

    },

    /* alternative alias syntax (click to show) */

    /* Advanced resolve configuration (click to show) */

  },

  performance: {

    hints: "warning", // enum

    maxAssetSize: , // int (in bytes),

    maxEntrypointSize: , // int (in bytes)

    assetFilter: function(assetFilename) {

      // Function predicate that provides asset filenames

      return assetFilename.endsWith('.css') || assetFilename.endsWith('.js');

    }

  },

  devtool: "source-map", // enum

  // enhance debugging by adding meta info for the browser devtools

  // source-map most detailed at the expense of build speed.

  context: __dirname, // string (absolute path!)

  // the home directory for webpack

  // the entry and module.rules.loader option

  //   is resolved relative to this directory

  target: "web", // enum

  // the environment in which the bundle should run

  // changes chunk loading behavior and available modules

  externals: ["react", /^@angular\//],

  // Don't follow/bundle these modules, but request them at runtime from the environment

  stats: "errors-only",

  // lets you precisely control what bundle information gets displayed

  devServer: {

    proxy: { // proxy URLs to backend development server

      '/api': 'http://localhost:3000'

    },

    contentBase: path.join(__dirname, 'public'), // boolean | string | array, static file location

    compress: true, // enable gzip compression

    historyApiFallback: true, // true for index.html upon 404, object for multiple paths

    hot: true, // hot module replacement. Depends on HotModuleReplacementPlugin

    https: false, // true for self-signed, object for cert authority

    noInfo: true, // only errors & warns on hot reload

    // ...

  },

  plugins: [

    // ...

  ],

  // list of additional plugins

  /* Advanced configuration (click to show) */

}