Functions for enabling, disabling and checking fullscreen mode.

fullscreen.coffee

# Credit: https://stackoverflow.com/a/65943962/1544937

activeFullScreen = ->

    Boolean document.isFullScreen or document.fullscreenElement or document.webkitFullscreenElement or document.mozFullScreenElement or document.msFullscreenElement

openFullScreen = ->

    if not activeFullScreen()

        if document.documentElement.requestFullScreen

            document.documentElement.requestFullScreen()

        else if document.documentElement.webkitRequestFullScreen

            document.documentElement.webkitRequestFullScreen()

        else if document.documentElement.mozRequestFullScreen

            document.documentElement.mozRequestFullScreen()

        else if document.msRequestFullscreen

            document.documentElement.msRequestFullscreen()

        true

    else

        false

closeFullScreen = ->

    if activeFullScreen()

        if document.cancelFullScreen

            document.cancelFullScreen()

        else if document.webkitCancelFullScreen

            document.webkitCancelFullScreen()

        else if document.mozCancelFullScreen

            document.mozCancelFullScreen()

        else if document.msExitFullscreen

            document.msExitFullscreen()

        true

    else

        false

fullscreen.js

// Credit: https://stackoverflow.com/a/65943962/1544937

var activeFullScreen, closeFullScreen, openFullScreen;

activeFullScreen = function() {
  return Boolean(document.isFullScreen || document.fullscreenElement || document.webkitFullscreenElement || document.mozFullScreenElement || document.msFullscreenElement);
};

openFullScreen = function() {
  if (!activeFullScreen()) {
    if (document.documentElement.requestFullScreen) {
      document.documentElement.requestFullScreen();
    } else if (document.documentElement.webkitRequestFullScreen) {
      document.documentElement.webkitRequestFullScreen();
    } else if (document.documentElement.mozRequestFullScreen) {
      document.documentElement.mozRequestFullScreen();
    } else if (document.msRequestFullscreen) {
      document.documentElement.msRequestFullscreen();
    }
    return true;
  } else {
    return false;
  }
};

closeFullScreen = function() {
  if (activeFullScreen()) {
    if (document.cancelFullScreen) {
      document.cancelFullScreen();
    } else if (document.webkitCancelFullScreen) {
      document.webkitCancelFullScreen();
    } else if (document.mozCancelFullScreen) {
      document.mozCancelFullScreen();
    } else if (document.msExitFullscreen) {
      document.msExitFullscreen();
    }
    return true;
  } else {
    return false;
  }
};