const {
  readdir, readFile, rename, writeFile, unlink,
} = require('fs').promises;
const { resolve } = require('path');
const { minify } = require('terser');
const rimraf = require('rimraf');
const rollup = require('rollup');
const { nodeResolve } = require('@rollup/plugin-node-resolve');
const replace = require('@rollup/plugin-replace');
const { babel } = require('@rollup/plugin-babel');

const tasks = [];
const inputFolder = 'build/media_source/vendor/bootstrap/js';
const outputFolder = 'media/vendor/bootstrap/js';

const getCurrentUnixTime = Math.round((new Date()).getTime() / 1000);

const createMinified = async (file) => {
  const initial = await readFile(resolve(outputFolder, file), { encoding: 'utf8' });
  const code = initial.replace('./dom.js', `./dom.js?${getCurrentUnixTime}`).replace('./popper.js', `./popper.js?${getCurrentUnixTime}`);
  const mini = await minify(code, { sourceMap: false, format: { comments: false } });
  await writeFile(resolve(outputFolder, file), code, { encoding: 'utf8' });
  await writeFile(resolve(outputFolder, file.replace('.js', '.min.js')), mini.code, { encoding: 'utf8' });
};

const build = async () => {
  // eslint-disable-next-line no-console
  console.log('Building ES6 Components...');

  const bundle = await rollup.rollup({
    input: resolve(inputFolder, 'index.es6.js'),
    plugins: [
      nodeResolve(),
      replace({
        'process.env.NODE_ENV': '\'production\'',
      }),
    ],
    external: [
      './base-component.js',
      './dom/data.js',
      './event-handler.js',
      './dom/manipulator.js',
      './selector-engine.js',
      './util/index.js',
    ],
    manualChunks: {
      alert: ['build/media_source/vendor/bootstrap/js/alert.es6.js'],
      button: ['build/media_source/vendor/bootstrap/js/button.es6.js'],
      carousel: ['build/media_source/vendor/bootstrap/js/carousel.es6.js'],
      collapse: ['build/media_source/vendor/bootstrap/js/collapse.es6.js'],
      dropdown: ['build/media_source/vendor/bootstrap/js/dropdown.es6.js'],
      modal: ['build/media_source/vendor/bootstrap/js/modal.es6.js'],
      popover: ['build/media_source/vendor/bootstrap/js/popover.es6.js'],
      scrollspy: ['build/media_source/vendor/bootstrap/js/scrollspy.es6.js'],
      tab: ['build/media_source/vendor/bootstrap/js/tab.es6.js'],
      toast: ['build/media_source/vendor/bootstrap/js/toast.es6.js'],
      popper: ['@popperjs/core'],
      dom: [
        'node_modules/bootstrap/js/src/base-component.js',
        'node_modules/bootstrap/js/src/dom/data.js',
        'node_modules/bootstrap/js/src/dom/event-handler.js',
        'node_modules/bootstrap/js/src/dom/manipulator.js',
        'node_modules/bootstrap/js/src/dom/selector-engine.js',
        'node_modules/bootstrap/js/src/util/index.js',
      ],
    },
  });

  await bundle.write({
    format: 'es',
    sourcemap: false,
    dir: outputFolder,
    chunkFileNames: '[name].js',
  });

  // closes the bundle
  await bundle.close();
};

const buildLegacy = async () => {
  // eslint-disable-next-line no-console
  console.log('Building Legacy...');

  const bundle = await rollup.rollup({
    input: resolve(inputFolder, 'index.es6.js'),
    plugins: [
      nodeResolve(),
      replace({
        'process.env.NODE_ENV': '\'production\'',
      }),
      babel({
        exclude: 'node_modules/core-js/**',
        babelHelpers: 'bundled',
        babelrc: false,
        presets: [
          [
            '@babel/preset-env',
            {
              corejs: '3.8',
              useBuiltIns: 'usage',
              targets: {
                chrome: '58',
                ie: '11',
              },
              loose: true,
              bugfixes: true,
              modules: false,
            },
          ],
        ],
      }),
    ],
    external: [],
  });

  await bundle.write({
    format: 'iife',
    sourcemap: false,
    name: 'Bootstrap',
    file: resolve(outputFolder, 'bootstrap.es5.js'),
  });

  // closes the bundle
  await bundle.close();
};

module.exports.bootstrapJs = async () => {
  rimraf.sync(resolve(outputFolder));

  try {
    await build(resolve(inputFolder, 'index.es6.js'));
    await unlink(resolve(outputFolder, 'index.es6.js'));
  } catch (error) {
    // eslint-disable-next-line no-console
    console.error(error);
    process.exit(1);
  }

  (await readdir(outputFolder)).forEach((file) => {
    if (!(file.startsWith('dom-') || file.startsWith('popper-'))) {
      tasks.push(createMinified(file));
    }
  });

  await Promise.all(tasks).catch((er) => {
    // eslint-disable-next-line no-console
    console.log(er);
    process.exit(1);
  });
  // eslint-disable-next-line no-console
  console.log('ES6 components ready ✅');

  try {
    await buildLegacy(inputFolder, 'index.es6.js');
    const es5File = await readFile(resolve(outputFolder, 'bootstrap.es5.js'), { encoding: 'utf8' });
    const mini = await minify(es5File, { sourceMap: false, format: { comments: false } });
    await writeFile(resolve(outputFolder, 'bootstrap.es5.min.js'), mini.code, { encoding: 'utf8' });
    // eslint-disable-next-line no-console
    console.log('Legacy done! ✅');
  } catch (error) {
    // eslint-disable-next-line no-console
    console.error(error);
    process.exit(1);
  }
};