require('dotenv').config();
const puppeteer = require('puppeteer');
const fs = require('fs');
const helper = require('./helper');
const params = require('../params');
const e = require('./elements');

class Page {
  constructor(name) {
    this.name = name;
    this.screenshotIndex = 0;
    this.meetingId;
    this.parentDir = this.getParentDir(__dirname);
  }

  getParentDir(dir) {
    const tmp = dir.split('/');
    tmp.pop();
    return tmp.join('/');
  }

  // Join BigBlueButton meeting
  async init(args, meetingId, newParams) {
    this.effectiveParams = newParams || params;
    const isModerator = this.effectiveParams.moderatorPW;
    this.browser = await puppeteer.launch(args);
    this.page = await this.browser.newPage({ context: `bbb-${this.effectiveParams.fullName}` });

    await this.setDownloadBehavior(`${this.parentDir}/downloads`);
    this.meetingId = await helper.createMeeting(params, meetingId);

    const joinURL = helper.getJoinURL(this.meetingId, this.effectiveParams, isModerator);

    await this.page.goto(joinURL);
    await this.waitForSelector(e.audioDialog);
    await this.click(e.closeAudio, true);
    const checkForGetMetrics = async () => {
      if (process.env.BBB_COLLECT_METRICS === 'true') {
        await this.getMetrics();
      }
    };
    await checkForGetMetrics();
  }

  async setDownloadBehavior(downloadPath) {
    const downloadBehavior = { behavior: 'allow', downloadPath };
    await this.page._client.send('Page.setDownloadBehavior', downloadBehavior);
  }

  // Run the test for the page
  async test() {
  }

  // Closes the page
  async close() {
    await this.browser.close();
  }

  // Gets the DOM elements being tested, as strings
  async getTestElements() {
  }

  // Get the default arguments for creating a page
  static getArgs() {
    return { headless: false, args: ['--no-sandbox', '--use-fake-ui-for-media-stream'] };
  }

  static getArgsWithVideo() {
    return {
      headless: false,
      args: [
        '--no-sandbox',
        '--use-fake-ui-for-media-stream',
        '--use-fake-device-for-media-stream',
        `--use-file-for-fake-video-capture=${process.env.VIDEO_FILE}`,
        '--allow-file-access'
      ],
    };
  }

  // Returns a Promise that resolves when an element does not exist/is removed from the DOM
  elementRemoved(element) {
    return this.page.waitFor(element => !document.querySelector(element), {}, element);
  }

  // Presses a hotkey (Ctrl, Alt and Shift can be held down while pressing the key)
  async hotkey(key, ctrl, alt, shift) {
    if (ctrl) { await this.page.keyboard.down('Control'); }
    if (alt) { await this.page.keyboard.down('Alt'); }
    if (shift) { await this.page.keyboard.down('Shift'); }

    await this.page.keyboard.press(key);

    if (ctrl) { await this.page.keyboard.up('Control'); }
    if (alt) { await this.page.keyboard.up('Alt'); }
    if (shift) { await this.page.keyboard.up('Shift'); }
  }

  // Presses the Tab key a set number of times
  async tab(count) {
    for (let i = 0; i < count; i++) {
      await this.page.keyboard.press('Tab');
    }
  }

  // Presses the Enter key
  async enter() {
    await this.page.keyboard.press('Enter');
  }

  // Presses the Down Arrow key a set number of times
  async down(count) {
    for (let i = 0; i < count; i++) {
      await this.page.keyboard.press('ArrowDown');
    }
  }

  // Presses the up arrow key a set number of times
  async up(count) {
    for (let i = 0; i < count; i++) {
      await this.page.keyboard.press('ArrowUp');
    }
  }

  async click(element, relief = false) {
    if (relief) await helper.sleep(1000);
    await this.waitForSelector(element);
    await this.page.click(element);
  }

  async type(element, text, relief = false) {
    if (relief) await helper.sleep(1000);
    await this.waitForSelector(element);
    await this.page.type(element, text);
  }

  async screenshot(relief = false) {
    if (relief) await helper.sleep(1000);
    const filename = `${this.name}-${this.screenshotIndex}.png`;
    const path = `${this.parentDir}/screenshots/${filename}`;
    await this.page.screenshot({ path });
    this.screenshotIndex++;
  }

  async paste(element) {
    await this.click(element);
    await this.page.keyboard.down('ControlLeft');
    await this.page.keyboard.press('KeyV');
    await this.page.keyboard.up('ControlLeft');
  }

  async waitForSelector(element) {
    await this.page.waitForSelector(element, { timeout: 0 });
  }

  async getMetrics() {
    const metricsObj = {};
    const dir = process.env.METRICS_FOLDER;
    const currentTimestamp = new Date();
    if (!fs.existsSync(dir)) {
      fs.mkdirSync(dir);
    }
    const metric = await this.page.metrics();
    metricsObj[`metricObj-${this.effectiveParams.fullName}`] = metric;
    const createFile = () => {
      try {
        fs.appendFileSync(`${dir}/metrics-${this.effectiveParams.fullName}-${currentTimestamp}.json`, `${JSON.stringify(metricsObj)}\n`);
      } catch (error) {
        console.log(error);
      }
    };
    createFile();
  }
}

module.exports = exports = Page;