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

class Page
{
  // Initializes the page
  async init(args)
  {
    this.browser = await puppeteer.launch(args);
    this.page = await this.browser.newPage();
  }

  // Navigates to a page
  async goto(page)
  {
    this.page.goto(page);
  }

  // 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: true, args: ["--no-sandbox", "--use-fake-ui-for-media-stream"]};
  }

  // Creates a BigBlueButton meeting
  async createBBBMeeting()
  {
    var meetingID = await helper.createMeeting(params);
    await this.joinBBBMeeting(meetingID);
    return meetingID;
  }

  // Navigates the page to join a BigBlueButton meeting
  async joinBBBMeeting(meetingID)
  {
    var joinURL = helper.getJoinURL(meetingID, params, true);
    await this.goto(joinURL);
  }

  // Joins a BigBlueButton as a listener
  async joinAudioListenOnly()
  {
    await this.page.waitFor(e.listenButton);
    await this.page.click(e.listenButton);
    await this.elementRemoved(e.audioDialog);
    console.log("Joined meeting as listener");
  }

  // Joins a BigBlueButton meeting with a microphone
  async joinAudioMicrophone()
  {
    await this.page.waitFor(e.microphoneButton);
    await this.page.click(e.microphoneButton);
    await this.page.waitFor(e.echoYes);
    await helper.sleep(500); // Echo test confirmation sometimes fails without this
    await this.page.click(e.echoYes);
    await this.elementRemoved(e.audioDialog);
    console.log("Joined meeting with microphone");
  }

  // Joins a BigBlueButton meeting without audio
  async joinWithoutAudio()
  {
    await this.page.waitFor(e.listenButton);
    await this.page.waitFor(e.closeAudio);
    await this.page.click(e.closeAudio);
    await this.elementRemoved(e.audioDialog);
    console.log("Joined meeting without audio");
  }

  // Returns a Promise that resolves when an element does not exist/is removed from the DOM
  elementRemoved(element)
  {
    return this.page.waitFor((element) => {return !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(var 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(var 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(var i = 0; i < count; i++)
    {
      await this.page.keyboard.press('ArrowUp');
    }
  }
};

module.exports = exports = Page;