Lynda Countdown

Shows the advancement / remaining time

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name           Lynda Countdown
// @description    Shows the advancement / remaining time
// @match          https://www.lynda.com/*.html*
// @run-at         document-end
// @version        1.1.1
// @grant          none
// @namespace      https://greasyfork.org/users/213706
// ==/UserScript==

NodeList.prototype.forEach = Array.prototype.forEach;

if(typeof unsafeWindow == "undefined") {
  unsafeWindow = window;
}

var LyndaCountdown = {
  videoList: {},
  totaltime: 0,
  watchtime: 0,

  /**
   * Called when the page loads
   * - calculate the total time
   * - the watch time
   * - add the event listeners
   * - display the countdown
   */
  init: function() {
    var toc = document.getElementById('toc');

    if(!toc) {
      return;
    }
    this.totaltime = 0;
    this.watchtime = 0;

    // Observer current video
    var observer = new MutationObserver(this.mutationCallback.bind(this));

    // Loop videos in Table Of Contents
    toc.querySelectorAll('.toc-video-item').forEach(function(node){
      let id       = node.getAttribute('data-video-id'),
          duration = node.querySelector('.video-duration').innerHTML.trim(),
          icon     = node.querySelector('.watch-trigger');

      if(!duration) {
        return
      }
      observer.observe(node, { attributes: true });

      // Get duration of video in seconds
      let [matching, h, m, s] = duration.match(/^(\d+h)? *(\d+m)? *(\d+s)?$/),
          time = 0;

      if(h) time += parseInt(h.slice(0,-1)) * 60 * 60;
      if(m) time += parseInt(m.slice(0,-1)) * 60;
      if(s) time += parseInt(s.slice(0,-1));

      // Check if the video has been watched or not
      let watched = icon.classList.contains('eye');

      // Add to the list
      this.videoList[id] = {time, watched};
      this.totaltime    += time;
      this.watchtime    += watched ? time : 0;

    }.bind(this));

    // Display the countdown
    this.render();
  },

  /**
   * Called whenever the attribute of a .toc-video-item changes
   * @param Array mutationsList
   */
  mutationCallback: function(mutationsList) {
    for(let mutation of mutationsList) {
      if (mutation.type !== 'attributes' || mutation.attributeName !== 'class') {
        return;
      }
      if(mutation.target.classList.contains('current')) {
        this.currentVideo(mutation.target);
      }
    }
  },

  /**
   * Called when the current active video changes
   * @param DOMElement node
   */
  currentVideo: function(node) {
    var id = node.getAttribute('data-video-id');

    // The user already watched this video
    if(this.videoList[id].watched) {
      return;
    }

    // Update the watch time
    this.videoList[id].watched = 1;
    this.watchtime += this.videoList[id].time;
    this.updateCountdown();
  },

  /**
   * Calculate the circumference of a circle knowing its radius
   * @param float r
   * @return float circ
   */
  circ: function(r) {
    return 2 * Math.PI * r;
  },

  /**
   * Called by init
   * - create the skeleton of the countdown
   * - update the progress bar
   * - display the countdown
   */
  render: function() {

    // https://codepen.io/xgad/post/svg-radial-progress-meters
    var r    = 22,
        circ = Math.round(this.circ(r), 3);

    // Create the HTML skeleton
    var div = unsafeWindow.document.createElement('div');
    div.setAttribute('id', 'countdown');
    div.innerHTML = `
            <div class="txt"></div>
            <svg class="clip" width="50" height="50">
                <circle class="bg" cx="50%" cy="50%" r="${r}"></circle>
                <circle class="arc" cx="50%" cy="50%" r="${r}"></circle>
            </svg>
            <style>
                #countdown {
          position: absolute;
          top: 12px;
          right: 120px;
                }
        #countdown .bg {
          fill: none;
          stroke-width: 5px;
          stroke: #ddd;
        }
        #countdown .arc {
          fill: none;
          stroke-width: 5;
          stroke: #ffb900;
          stroke-linecap: round;
          stroke-dasharray: ${circ};
          stroke-dashoffset: 0;
                  transform: rotate(-90deg);
                  transform-origin: 50% 50%;
                  animation: big 1.5s ease-in-out;
        }
        #countdown .txt {
          position: absolute;
          left: 0;
          top: 50%;
                    transform: translateY(-50%);
                    width: 100%;
          text-align: center;
                    white-space: nowrap;
        }
        </style>`;   

    // Update the progress bar
    this.countdown = {
      circ,
      txtElem: div.querySelector('.txt'),
      arcElem: div.querySelector('.arc'),
      totalTxt: this.timeToHuman(this.totaltime)
    };
    this.updateCountdown();

    // Add to the page
    document.querySelector('.title-banner').appendChild(div);
  },

  /**
   * Updates the countdown
   * @param integer percent     - Ex: 5
   * @param string remainingTxt - Ex: 2h 30m
   */
  updateCountdown: function() {
    var remains = this.totaltime - this.watchtime,
        percent = remains <= 0 ? 100 : Math.round(this.watchtime / this.totaltime * 100, 3),
        deg     = Math.ceil(this.countdown.circ * (100 - percent) / 100);

    var txt_remains,
        txt_title;

    if(percent == 100) { 
      txt_remains = 'Done';
      txt_title   = 'You have completed 100% of this course';

    } else {
      txt_remains = `${this.timeToHuman(remains)}<br>left`;
      txt_title   = `You have completed ${parseInt(percent)}% of this course (${this.timeToHuman(this.watchtime)} / ${this.countdown.totalTxt})`;
    }

    this.countdown.arcElem.style['stroke-dashoffset'] = deg;
    this.countdown.txtElem.setAttribute('title', txt_title);
    this.countdown.txtElem.innerHTML = txt_remains;
  },

  /**
   * Returns a string to display the time
   * @param integer seconds
   * @return string time
   */
  timeToHuman(seconds) {
    if(seconds <= 60) {
      return seconds + 's';
    }
    if(seconds <= 3600) {
      return parseInt(seconds / 60) + 'm '
            + (seconds % 60).toString().padStart(2, '0') + 's';
    }
    return parseInt(seconds / 3600) + 'h '
        + (parseInt(seconds / 60) % 60).toString().padStart(2, '0') + 'm';
  }
};

unsafeWindow.onload = setTimeout(function(){
  LyndaCountdown.init();
},500);