#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <netinet/in.h>

#include "constants.h"
#include "question.h"
#include "packet.h"

DNSQuestion * dns_question_create (const char *name, int type, int klass) {
	DNSQuestion *question;
	
	question = (DNSQuestion *) malloc (sizeof (DNSQuestion));
	
	if (question == NULL) return NULL;
	
	memset (question, 0, sizeof (DNSQuestion));
	
	strncpy (question->qname, name, 255);
	
	question->qtype = type;
	question->qklass = klass;
	
	return question;
}

void dns_question_pack_data (DNSQuestion *question, DNSPacket *packet) {
	uint16_t t16;
	
	dns_packet_compress_name (packet, question->qname);
	
	t16 = htons (question->qtype);
	memcpy (&packet->rdata[packet->rdlength], &t16, 2);
	packet->rdlength += 2;
	
	t16 = htons (question->qklass);
	memcpy (&packet->rdata[packet->rdlength], &t16, 2);
	packet->rdlength += 2;
}

void dns_question_free (DNSQuestion *question) {
	free (question);
}

int dns_question_parse_question_from_packet (DNSPacket *packet) {
	DNSQuestion *question;
	uint16_t t16;
	
	question = (DNSQuestion *) malloc (sizeof (DNSQuestion));
	
	if (question == NULL) return -1;
	
	memset (question, 0, sizeof (DNSQuestion));
	
	if (dns_packet_expand_name (question->qname, packet, &packet->rdread) < 0) {
		dns_question_free (question);
		return -1;
	}
	
	if (packet->rdlength < packet->rdread + 4) {
		dns_question_free (question);
		return -1;
	}
	
	memcpy (&t16, &packet->rdata[packet->rdread], sizeof (t16));
	question->qtype = ntohs (t16);
	packet->rdread += 2;
	
	memcpy (&t16, &packet->rdata[packet->rdread], sizeof (t16));
	question->qklass = ntohs (t16);
	packet->rdread += 2;
	
	if (question->qklass != RR_CLASS_IN &&
	    question->qklass != RR_CLASS_CH &&
	    question->qklass != RR_CLASS_HS) {
		dns_question_free (question);
		return -1;
	}
	
	/* TODO: Validar el qtype */
	
	/* Anexar a la lista de preguntas */
	packet->questions = g_list_append (packet->questions, question);
	return 0;
}