public function setAmount($amount)
{
if (!is_int($amount)) {
throw new InvalidArgumentException("Integer expected. Amount is always in cents");
}
if ($amount <= 0) {
throw new InvalidArgumentException("Amount must be a positive number");
}
if ($amount >= 1000000000000000.0) {
throw new InvalidArgumentException("Amount is too high");
}
$this->parameters['amount'] = $amount;
}