// ==UserScript==
// @name         soundcloud scroll queue
// @version      1.0
// @description  Adds a button that automatically scrolls the queue until disabled
// @author       bhackel
// @match        https://soundcloud.com/*
// @grant        none
// @run-at       document-start
// @noframes
// @namespace https://greasyfork.org/en/users/324178-bhackel
// @downloadURL none
// ==/UserScript==

(function() {
    'use strict';

    function setup() {
        var btn = document.createElement("Button");
        btn.className = "bhackelSCScroll sc-button sc-button-medium";
        btn.innerHTML = "Scroll Down";
        btn.onclick = function(){ start(this); };

        var queue_panel = document.getElementsByClassName("queue__panel")[0];
        if (queue_panel) {
            queue_panel.insertBefore(btn, queue_panel.children[1]);
        } else {
            setTimeout(setup, 1000);
        }
    }

    function start(d){
        if (d.interval){
            clearInterval(d.interval);
            d.interval = 0;
            d.innerHTML='Scroll Down';
        } else {
            d.interval=setInterval(function(){
                scroll();
            },1000);
            d.innerHTML='Stop Scrolling';
        }
    }

    function scroll() {
        var scrollableQueue = document.getElementsByClassName("queue__scrollableInner g-scrollable-inner").item(0);
        var queueContainer = document.getElementsByClassName("queue__itemsHeight").item(0);
        var scrollToHeight = parseInt(queueContainer.style.height);
        scrollableQueue.scroll(0,scrollToHeight);
    }

    setup();

})();