'use strict';

const fs = require('fs');
const glob = require('glob');
const Mocha = require('mocha');
const path = require('path');
const webdriver = require('selenium-webdriver');

const Snapshot = require('./Snapshot');

let snapshot;
let takeScreenshots = false;

function startDevServer() {
  const server = require('@stencil/dev-server/dist'); // TODO: fix after stencil-dev-server PR #16 is merged
  const cmdArgs = ['--config', path.join(__dirname, '../stencil.config.js'), '--no-open'];

  return server.run(cmdArgs);
}

function getTestFiles() {
  return new Promise((resolve, reject) => {
    const src = path.join(__dirname, '../src/**/*.e2e-spec.js');
    glob(src, (err, files) => {
      if (err) {
        reject(err);
      } else {
        resolve(files);
      }
    });
  });
}

function processCommandLine() {
  process.argv.forEach(arg => {
    if (arg === '--snapshot') {
      takeScreenshots = true;
    }
  });
}

function registerE2ETest(desc, tst) {
  // NOTE: Do not use an arrow function here because: https://mochajs.org/#arrow-functions
  it(desc, async function() {
    const driver = new webdriver.Builder().forBrowser('chrome').build();
    await tst(driver);
    if (takeScreenshots) {
      await snapshot.takeScreenshot(driver, {
        name: this.test.fullTitle()
      });
    }
    return driver.quit();
  });
}

async function run() {
  const mocha = new Mocha({
    timeout: 5000,
    slow: 2000
  });

  processCommandLine();

  snapshot = new Snapshot({
    platformDefaults: {
      params: {
        height: 800,
        width: 400
      }
    }
  });

  const devServer = await startDevServer();

  const files = await getTestFiles();
  files.forEach(f => mocha.addFile(f));
  mocha.run(function(failures) {
    process.on('exit', function() {
      process.exit(failures); // exit with non-zero status if there were failures
    });
    devServer.close();
  });
}

module.exports = {
  register: registerE2ETest,
  run: run
};