InvoiceExist::getPreparedEmailData

public function getPreparedEmailData()
{
	$result = [];
	if ($this->isSendingInvoice())
	{
		$templateId = (int)$this->getCalculateParameter('EMAIL_TEMPLATE_ID');
		$result = [
			'EMAIL_ID' => (int)$this->recurringFields['EMAIL_ID'],
			'TEMPLATE_ID' => $templateId > 0 ? $templateId : null
		];
	}
	return $result;
}