const chromeManifest = require('../react-devtools-extensions/chrome/manifest.json');

const firefoxManifest = require('../react-devtools-extensions/firefox/manifest.json');

const minChromeVersion = parseInt(chromeManifest.minimum_chrome_version, 10);

const minFirefoxVersion = parseInt(

  firefoxManifest.applications.gecko.strict_min_version,

  10,

);

validateVersion(minChromeVersion);

validateVersion(minFirefoxVersion);

function validateVersion(version) {

  if (version > 0 && version < 200) {

    return;

  }

  throw new Error('Suspicious browser version in manifest: ' + version);

}

module.exports = api => {

  const isTest = api.env('test');

  const targets = {};

  if (isTest) {

    targets.node = 'current';

  } else {

    targets.chrome = minChromeVersion.toString();

    targets.firefox = minFirefoxVersion.toString();

    let additionalTargets = process.env.BABEL_CONFIG_ADDITIONAL_TARGETS;

    if (additionalTargets) {

      additionalTargets = JSON.parse(additionalTargets);

      for (const target in additionalTargets) {

        targets[target] = additionalTargets[target];

      }

    }

  }

  const plugins = [

    ['@babel/plugin-transform-flow-strip-types'],

    ['@babel/plugin-proposal-class-properties', {loose: false}],

  ];

  if (process.env.NODE_ENV !== 'production') {

    plugins.push(['@babel/plugin-transform-react-jsx-source']);

  }

  return {

    plugins,

    presets: [

      ['@babel/preset-env', {targets}],

      '@babel/preset-react',

      '@babel/preset-flow',

    ],

  };

};