Making the world a better place by disabling SoundCloud autoplay

mysoundcloud.js

// ==UserScript==
// @name         mysoundcloud
// @namespace    https://github.com/deluvas
// @version      0.1.2
// @description  A collection of tweaks to improve the SoundCloud user experience
// @author       deluvas
// @match        *://soundcloud.com/*
// @grant        none
// @run-at       document-start
// ==/UserScript==

// TODO: do not allow last item in playlist to continue

(function () {
  /**
   * CUSTOMIZE THE SCRIPT BY MODIFYING THESE SETTINGS
   */
  let settings = {
    disable_autoplay: true
  }
 
  function disableAutoplay() {
    let progressBar = document.querySelector( "div.playbackTimeline__progressWrapper" );
    let pauseControl = document.querySelector( "button.playControls__play" );
    let repeatControl = document.querySelector( "button.repeatControl" );
    let prevControl = document.querySelector( "button.playControls__prev" );    
    let nextControl = document.querySelector( "button.playControls__next" );

    if ( progressBar == null || pauseControl == null ) {
      console.warn( "Progress bar and/or controls not found" )
      return;
    }
    
    isInPlaylist = () => {
      let songBadge = document.querySelector( "div.playControls__soundBadge a.playbackSoundBadge__avatar");
      if ( songBadge == null ) {
        debug.warn( "Couldn't figure out if song is in playlist or not!" );
        return false;
      }      
      
      let href = songBadge.getAttribute( "href" );
      if ( href.match( /\?in=(.+)\/sets\// ) ) {
        return true;
      }
      
      return false;
    }    
    
    getRepeatMode = () => {
      let classes = repeatControl.className;
      if ( classes.indexOf( "m-none" ) >= 0 ) {
        return 0;
      } else if ( classes.indexOf( "m-all" ) >= 0 ) {
        return 2;
      } else {
        return 1; // repeat once
      }
    }
    
    resetSongSeek = () => {
      nextControl.click();
      prevControl.click();
    }
    
    // The progress bar contains 2 attributes which show the songs maximum time
    // and current time in seconds. the current time is updated every 1s so one can
    // check when the song is near its end
    let observer = new MutationObserver( ( mutations ) => {
      for ( let mutation of mutations ) {
        if ( mutation.type === "attributes" && mutation.attributeName == "aria-valuenow" ) {
          let currentValue = parseFloat( progressBar.getAttribute( "aria-valuenow" ) );
          let maxValue = parseFloat( progressBar.getAttribute( "aria-valuemax" ) );

          if ( currentValue >= maxValue - 1.250 ) { // end - 1.250s (progress is updated every 1s)
            if ( isInPlaylist() ) {
              console.debug( "Allowing autoplay since song is in playlist" )
            } 
            else {
              resetSongSeek(); 
              if ( getRepeatMode() === 0 ) {
                pauseControl.click();
                console.debug( "Stopping autoplay. Pausing song." );              
              } else {
                console.debug( "Repeating song" );
              }
              break;
            }
          }
          break;
        }      
      } 
    } );
    observer.observe( progressBar, { attributes: true } );
  }

  if ( settings.disable_autoplay ) {
    setTimeout( disableAutoplay, 750 );
  }
}());