const puppeteer = require('puppeteer');
const containerized = require('containerized');

const MY_PACKAGE_SELECTOR_ID =
  'table[style="margin-top:-10px;"] tr:first-child+tr';
const DATA_SELECTOR = 'packagecol3';

const DATA_USAGE_REGEX = /\d+\.\d{0,2}/g;
const KEYS = ['live', 'flexibytes'];
var browser;

async function getUsage() {
  const page = await browser.newPage();

  let defaultMetric = {
    usedBytes: null,
    totalBytes: null,
  };

  let metrics = {
    live: defaultMetric,
    flexibytes: defaultMetric,
    aggregate: defaultMetric,
  };

  try {
    await page.goto('http://portal.actcorp.in/group/blr/myaccount');
    await page.click(MY_PACKAGE_SELECTOR_ID);
    await page.waitFor(3000),
      (dataUsage = await page.evaluate(sel => {
        let elements = document.getElementsByClassName(sel);

        if (!elements || elements.length < 4) {
          return '0.00 0.00';
        }
        let usage = {
          live: elements[3].innerText,
          aggregate: '0.00 GB (Quota 800.00 GB)',
        };
        if (elements.length >= 6) {
          usage['flexibytes'] = elements[5].innerText;
        }
        return usage;
      }, DATA_SELECTOR));

    // ['0.00 GB (Quota 800.00 GB)', '102.58 GB(Quota 100.00 GB)']
    KEYS.map(key => {
      dataUsage[key] = dataUsage[key]
        .match(DATA_USAGE_REGEX)
        .map(x => parseFloat(x) * Math.pow(10, 6));
    });
    dataUsage.aggregate = { usedBytes: 0, totalBytes: 0 };

    KEYS.map(key => {
      dataUsage[key] = {
        usedBytes: dataUsage[key][0],
        totalBytes: dataUsage[key][1],
      };
      dataUsage.aggregate.usedBytes += dataUsage[key].usedBytes;
      dataUsage.aggregate.totalBytes += dataUsage[key].totalBytes;
    });

    metrics = dataUsage;
  } catch (e) {
    console.log("Couldn't scrape ACT page, faced an error");
    console.log(e);
    return null;
  } finally {
    page.close();
    return metrics;
  }
}

function chromeLaunchConfig() {
  let defaultArgs = [];
  if (containerized()) {
    defaultArgs = ['--no-sandbox', '--disable-setuid-sandbox'];
  }
  var options = {
    // These are set for Docker usage
    // https://github.com/alekzonder/docker-puppeteer#before-usage
    args: defaultArgs.concat(
      process.env.hasOwnProperty('PROXY_SERVER')
        ? [`--proxy-server=${process.env['PROXY_SERVER']}`]
        : []
    ),
  };

  if (process.env.hasOwnProperty('DISABLE_HEADLESS')) {
    options.headless = false;
  }

  if (process.env.hasOwnProperty('CHROME_BIN')) {
    options.executablePath = process.env['CHROME_BIN'];
  }

  console.log('Launching Chrome with args:');
  console.log(options);

  return options;
}

// Async IIFE FTW
(async () => {
  browser = await puppeteer.launch(chromeLaunchConfig());
  console.log('Browser Initialized');
})();

module.exports = {
  getUsage: getUsage,
};