html5 video keyboard control

video_keyboard_control.user.js

// ==UserScript==
// @name         video keyboard control
// @namespace    https://github.com/mareku
// @version      1.6
// @description  html5 video keyboard control
//               play & Stop = K
//               Back        = J
//               Advance     = L
//               Mute        = M
//               Speed Down  = Z
//               Speed Riset = X
//               Speed Up    = C
// @author       mareku
// @match        *
// @include      *
// @updateURL    https://gist.github.com/mareku/32897a2cf68d627a513cf336e3102de1/raw
// ==/UserScript==

window.addEventListener('load',function () {
  var vid = document.querySelector('video') || document.getElementsByTagName("video")[0];
  if (!vid) {
    console.log('Not video');
    return;
  }
  // inputタグなどにフォーカス中のときは無効
  if (['input', 'textarea'].includes(document.activeElement.tagName.toLocaleLowerCase())) {
    return;
  }

  var play_toggle = 75, // K
  back = 74,            // J
  advance = 76,         // L
  mute = 77,            // M
  speed_down_key = 90,  // Z
  speed_riset_key = 88, // X
  speed_up_key = 67;    // C

  var criteria_speed = 0.25;

  document.addEventListener('keydown', function(e){
  if ( !e.shiftKey || !e.altKey || !e.ctrlKey || !e.metaKey ) {

      var current_rate = vid.playbackRate;
      var kcode = e.keyCode

      switch (kcode) {
        case back: // back -10s
          vid.currentTime -= 10;
          e.preventDefault();
          e.stopPropagation();
          break;
        case advance: // advance +10s
          vid.currentTime += 10;
          e.preventDefault();
          e.stopPropagation();
          break;
        case speed_down_key: // Reproducing Speed Down
          if (0 < current_rate) {
            vid.playbackRate -= criteria_speed;
          }
          e.preventDefault();
          e.stopPropagation();
          break;
        case speed_riset_key: // Reproducing Speed Riset
          vid.playbackRate = 1;
          e.preventDefault();
          e.stopPropagation();
          break;
        case speed_up_key: // Reproducing Speed Up
          if (current_rate < 3) {
            vid.playbackRate += criteria_speed;
          }
          e.preventDefault();
          e.stopPropagation();
          break;
        case play_toggle: // Play & Stop Toggle
          if (vid.paused) {
            vid.play();
          } else {
            vid.pause();
          }
          e.preventDefault();
          e.stopPropagation();
          break;
        case mute: // mute
          if (vid.muted) {
            vid.muted = false;
          } else {
            vid.muted = true;
          }
          e.preventDefault();
          e.stopPropagation();
          break;
        case 48:
        case 49:
        case 50:
        case 51:
        case 52:
        case 53:
        case 54:
        case 55:
        case 56:
        case 57:
          // 任意の場所に飛ぶ
          var num = String.fromCharCode(kcode);
          vid.currentTime = vid.duration * (num / 10);
          e.preventDefault();
          e.stopPropagation();
          break;
      }
    }
  } ,true);
});