Order::getDealPrimaryContactId

private function getDealPrimaryContactId(int $dealId): ?int
{
	$contacts = DealContactTable::getDealBindings($dealId);
	foreach ($contacts as $contact)
	{
		if ($contact['IS_PRIMARY'] !== 'Y')
		{
			continue;
		}

		return (int)$contact['CONTACT_ID'];
	}

	return null;
}