/**
* Encode the header section of the message
*
* @param \LibDNS\Encoder\EncodingContext $encodingContext
* @param \LibDNS\Messages\Message $message
* @return string
* @throws \UnexpectedValueException When the header section is invalid
*/
private function encodeHeader(EncodingContext $encodingContext, Message $message)
{
$header = ['id' => $message->getID(), 'meta' => 0, 'qd' => $message->getQuestionRecords()->count(), 'an' => $message->getAnswerRecords()->count(), 'ns' => $message->getAuthorityRecords()->count(), 'ar' => $message->getAdditionalRecords()->count()];
$header['meta'] |= $message->getType() << 16;
$header['meta'] |= $message->getOpCode() << 11;
$header['meta'] |= (int) $message->isAuthoritative() << 10;
$header['meta'] |= (int) $encodingContext->isTruncated() << 9;
$header['meta'] |= (int) $message->isRecursionDesired() << 8;
$header['meta'] |= (int) $message->isRecursionAvailable() << 7;
$header['meta'] |= $message->getResponseCode();
return pack('n*', $header['id'], $header['meta'], $header['qd'], $header['an'], $header['ns'], $header['ar']);
}
