const path = require('path')
const TerserPlugin = require('terser-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const PrerenderSPAPlugin = require('prerender-spa-plugin')
const Renderer = PrerenderSPAPlugin.PuppeteerRenderer
const CopyPlugin = require('copy-webpack-plugin')
const { InjectManifest } = require('workbox-webpack-plugin')
const ManifestPlugin = require('webpack-manifest-plugin')
const ImageminPlugin = require('imagemin-webpack-plugin').default
const { JSDOM } = require('jsdom')
const tempy = require('tempy')
const fs = require('fs')

const magicFile = (text) => {
  const p = tempy.file()
  fs.writeFileSync(p, text)
  return p
}

// const magicAppend = (orig, text, sep = '\n') => magicFile(fs.readFileSync(orig) + sep + text)

const jsMin = {
  pure_funcs: ["F2", "F3", "F4", "F5", "F6", "F7", "F8", "F9", "A2", "A3", "A4", "A5", "A6", "A7", "A8", "A9"],
  pure_getters: true,
  keep_fargs: false,
  unsafe_comps: true,
  unsafe: true,
  compress: true,
  mangle: true,
}

module.exports = {
  output: {
    filename: "main.js",
    path: path.join(__dirname, "dist"),
    publicPath: "/"
  },
  module: {
    rules: [{
      test: /\.elm$/,
      exclude: [/elm-stuff/, /node_modules/],
      loader: 'elm-webpack-loader',
      options: {
        optimize: true
      }
    }],
  },
  plugins: [
    new ManifestPlugin(),
    new ImageminPlugin({
      disable: false,
      pngquant: {
        quality: '95-100'
      }
    }),
    new TerserPlugin({
      terserOptions: jsMin,
    }),
    new HtmlWebpackPlugin({
      hash: true,
      meta: {
        viewport: 'width=device-width, initial-scale=1'
      }
    }),
    new CopyPlugin([{ from: 'data', to: 'data' }, { from: 'wand.js', to: 'wand.js' }]),
    new PrerenderSPAPlugin({
      staticDir: path.join(__dirname, 'dist'),
      routes: ROUTES,
      minify: {
        minifyCSS: {
          compatibility: 'ie9',
          level: 2
        },
        minifyJS: jsMin,

        collapseBooleanAttributes: true,
        collapseWhitespace: true,
        removeRedundantAttributes: true,
        removeScriptTypeAttributes: true,
        removeStyleLinkTypeAttributes: true,

        removeComments: true,
        sortAttributes: true,
        sortClassName: true,
      },
      renderer: new Renderer({
        renderAfterTime: 500,
      }),
      postProcess(renderedRoute) {
        const dom = new JSDOM(renderedRoute.html, { runScripts: 'outside-only' })
        dom.window.eval(`
            const wandTarget = document.createElement('script')
            wandTarget.src = '/wand.js'
            document.body.appendChild(wandTarget)
          `)
        return {
          ...renderedRoute,
          html: dom.serialize(),
        }
      },
    }),
    new InjectManifest({
      importWorkboxFrom: 'local',
      swSrc: magicFile(`
          workbox.routing.registerNavigationRoute('/index.html');
          workbox.precaching.precacheAndRoute(self.__precacheManifest);
        `),
      swDest: 'sw.js',
    }),
  ]
}