rollDice = function() {
   // wait until button is clickable again
   if (!$('#double_your_btc_bet_hi_button').prop('disabled')) {
 
      // win: double amount / reset to 1 if lost [multiplier] rounds
 
      // this option is useful 'cause the max. win profit is 99, so after you spent
      // 127 [ ((2^7)-1) or 1+2+4+8+16+32+64 ] it's impossible to make profit anymore
      // since there's no 128 option (so set it max. to 6!)
 
      // decrease the multiplier to keep the losses low, but the chance of winning will
      // also drop if you loose very often consecutively
      if ($('#double_your_btc_bet_lose').html() !== '' && multiplier < 5) {
         $('#double_your_btc_2x').click();
         multiplier++;
 
      // lose: reset to 1
      } else {
         $('#double_your_btc_min').click();
         multiplier = 1;
      }
 
      // click hi or lo button randomly
      if (Math.random() >= 0.5) {
         $('#double_your_btc_bet_lo_button').click();
      } else {
         $('#double_your_btc_bet_hi_button').click();
      }
   }
 
   // wait 250ms before next run. don't set the timeout to zero because if the button is still
   // unclickable this will cause very high cpu usage!
   setTimeout(rollDice, 250);
};
 
// initialise
multiplier = 1;
rollDice();