/**
* How much time the client must wait before it will be
* allowed to try to log-in next.
* The return value is 0 if no wait is required.
*/
private function getNextLoginTimeout()
{
global $wgMemc;
$val = $wgMemc->get($this->getMemCacheKey());
$elapse = time() - $val['lastReqTime'];
// in seconds
$canRetryIn = ApiLogin::calculateDelay($val['count']) - $elapse;
return $canRetryIn < 0 ? 0 : $canRetryIn;
}