const HtmlWebpackPlugin = require('html-webpack-plugin');
const CspHtmlWebpackPlugin = require('csp-html-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const merge = require('webpack-merge');
const base = require('./webpack.config');
const path = require('path');
const nonce = require('./app/src/utils/createNonce')();

// merges webpack.config.js with production specific configs
module.exports = merge(base, {
  // enables optimizations for production mode
  // sets process.env.NODE_ENV to 'production'
  mode: 'production',
  // nosources-source-map exposes filenames/structure for stack traces but not the rest of the soruce cdoe
  // devtool: 'source-map', //https://webpack.js.org/configuration/devtool/ && https://github.com/webpack/webpack/issues/5627#issuecomment-389492939
  // optimization: {
  //   minimize: false,
  // },
  plugins: [
    // miniCssExtractPlugin is included here because it's used as a loader in wepack.config.js
    new MiniCssExtractPlugin(),
    // simplifies creation of HTML files that serve webpack bundles
    // creates a index.html file in the dist folder using index.html as a template
    new HtmlWebpackPlugin({
      template: path.resolve(__dirname, 'app/src/public/index-prod.ejs'),
      filename: 'index-prod.html',
      nonce: nonce
    })
    // TODO: Fix CSP so it will work with external style sheets
    // // enerate meta content for your Content Security Policy tag and input the correct data into your HTML template
    // // Content-Security-Policy response header allows web site administrators to control resources the user agent is allowed to load for a given page
    // // policies mostly involve specifying server origins and script endpoints. This helps guard against cross-site scripting attacks
    // new CspHtmlWebpackPlugin(
    //   {
    //     // only include URIs from the base URL /port
    //     // TODO: update this URI to allow requests to github
    //     "base-uri": ["'self'"],
    //     // object-src is a legacy html feature that's not supported anymore
    //     // the CSP is restricting this type of element
    //     "object-src": ["'none'"],
    //     // specifies valid directories for JS scripts
    //     // doc can only be served from same url scheme/PORT
    //     //TODO: may also need to update this for github
    //     "script-src": ["'self'"],
    //     // only allow styles from the same URL/port or styles that have a specific nonce
    //     // the nonce is necessary here so that Material UI styles can render with the CSP
    //     // https://material-ui.com/styles/advanced/#content-security-policy-csp
    //     // https://github.com/reZach/secure-electron-template/issues/14metap
    //     "style-src": ["'self'", `'nonce-${nonce}'`],
    //     // does not allow nested browsing contexts (frame/iframe)
    //     "frame-src": ["'none'"],
    //     // do not allow worker scripts
    //     "worker-src": ["'none'"],
    //   },
    //   {
    //     // entry for which policy rules are allowed to include hashes
    //     hashEnabled: {
    //       "style-src": false,
    //     },
    //   }
    // ),
  ]
});