Auto Scroll Up and Down + Stop on Mouse Click

Hi There!
I have the following script to auto scrollup and scrolldown my page. Works like a charm.
But, also I need to add a stop function on mousedown or onclick.
Is it possible?
Thanks in advance.

Code:

---

(function() {
  'use strict';

  var dbh,sto,num=50,temp=0,scrolldelay=3000;

function init(){
    dbh=document.body.offsetHeight;
    pageScroll();
 }

function pageScroll() {
    window.scrollBy(0,num);
    temp+=num;
if((temp>=dbh)||(temp<=0)){
    num=-num;
 }
  sto=setTimeout(function(){pageScroll();},scrolldelay);
 }
  window.addEventListener?
  window.addEventListener('load',init,false):
  window.attachEvent('onload',init);
})();

---

Maybe (untested):

Code:

---

(function() {
  'use strict';

  var dbh,sto,num=50,temp=0,scrolldelay=3000;

function init(){
    dbh=document.body.offsetHeight;
    pageScroll();
 }

function stopScroll(){
    clearTimeout(sto);
 }

function pageScroll() {
    window.scrollBy(0,num);
    temp+=num;
if((temp>=dbh)||(temp<=0)){
    num=-num;
 }
  sto=setTimeout(function(){pageScroll();},scrolldelay);
 }
  if(window.addEventListener){
    window.addEventListener('load', init, false);
    document.addEventListener('mousedown', stopScroll, false);
  } else if (window.attachEvent){
    window.attachEvent('onload', init);
    document.attachEvent('onmousedown', stopScroll);
  }
})();

---

Something like that I would think.