const webpack = require("webpack");
const path = require("path");
const BabelMinifyPlugin = require("babel-minify-webpack-plugin");

module.exports.resolve = {
  extensions: [".ts", ".js", ".json", ".tsx"],
  alias: {
    react: "preact-compat",
    "react-dom": "preact-compat",
    // Not necessary unless you consume a module using `createClass`
    "create-react-class": "preact-compat/lib/create-react-class",
    // Not necessary unless you consume a module requiring `react-dom-factories`
    "react-dom-factories": "preact-compat/lib/react-dom-factories",
  },
};

module.exports.plugins = [
  // Ignore moment.js locales
  new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/),
  // Color.js is bloated, it contains all color definitions for all material color sets.
  new webpack.NormalModuleReplacementPlugin(
    /@polymer\/paper-styles\/color\.js$/,
    path.resolve(__dirname, "../src/util/empty.js")
  ),
  // Ignore roboto pointing at CDN. We use local font-roboto-local.
  new webpack.NormalModuleReplacementPlugin(
    /@polymer\/font-roboto\/roboto\.js$/,
    path.resolve(__dirname, "../src/util/empty.js")
  ),
];

module.exports.optimization = {
  minimizer: [
    // Took options from Polymer build tool
    // https://github.com/Polymer/tools/blob/master/packages/build/src/js-transform.ts
    new BabelMinifyPlugin(
      {
        // Disable the minify-constant-folding plugin because it has a bug relating
        // to invalid substitution of constant values into export specifiers:
        // https://github.com/babel/minify/issues/820
        evaluate: false,

        // TODO(aomarks) Find out why we disabled this plugin.
        simplifyComparisons: false,

        // Prevent removal of things that babel thinks are unreachable, but sometimes
        // gets wrong: https://github.com/Polymer/tools/issues/724
        deadcode: false,

        // Disable the simplify plugin because it can eat some statements preceeding
        // loops. https://github.com/babel/minify/issues/824
        simplify: false,

        // This is breaking ES6 output. https://github.com/Polymer/tools/issues/261
        mangle: false,
      },
      {}
    ),
  ],
};