import { execSync } from 'child_process';
import electronPath from 'electron';
import { writeFile } from 'fs/promises';
import { join } from 'path';

import { fileURLToDirname } from '../config/utils.js';

const thisDir = fileURLToDirname(import.meta.url);

/**
 * Returns versions of electron vendors
 * The performance of this feature is very poor and can be improved
 * @see https://github.com/electron/electron/issues/28006
 *
 * @returns {NodeJS.ProcessVersions}
 */
function getVendors() {
  const output = execSync(`${electronPath} -p "JSON.stringify(process.versions)"`, {
    env: { 'ELECTRON_RUN_AS_NODE': '1' },
    encoding: 'utf-8',
  });

  return JSON.parse(output);
}

/**
 * Generates the `.browserlistrc` and `.electron-vendors.cache.json` files.
 *
 * @returns Promise<void>
 */
function updateVendors() {
  const electronRelease = getVendors();

  const nodeMajorVersion = electronRelease.node.split('.')[0];
  const chromeMajorVersion = electronRelease.v8.split('.')[0] + electronRelease.v8.split('.')[1];

  const browserslistrcPath = join(thisDir, '../.browserslistrc');

  return Promise.all([
    writeFile(
      join(thisDir, '../.electron-vendors.cache.json'),
      JSON.stringify({
        chrome: chromeMajorVersion,
        node: nodeMajorVersion,
      }, null, 2) + '\n',
    ),

    writeFile(browserslistrcPath, `Chrome ${chromeMajorVersion}\n`, 'utf8'),
  ]);
}

updateVendors().catch((err) => {
  console.error(err);
  process.exit(1);
});