#include <pcap.h>
#include <string.h>

#include "host.h"

int get_interface_name(struct host *host)
{
	pcap_if_t *alldevs;
	char errbuf[PCAP_ERRBUF_SIZE];

	if (pcap_findalldevs(&alldevs, errbuf) == -1) {
		dprintf(2, "Error finding devices: %s\n", errbuf);
		return -1;
	}

	for (pcap_if_t *it = alldevs; it != NULL; it = it->next) {
		if (!(it->flags & PCAP_IF_LOOPBACK)) {
			strcpy(host->interface, it->name);
			for (pcap_addr_t *a = it->addresses; a != NULL; a = a->next) {
				if (a->addr && a->addr->sa_family == AF_INET) { // Only IPv4
					struct sockaddr_in *sa = (struct sockaddr_in *)a->addr;
					strcpy(host->ip, inet_ntoa(sa->sin_addr));
					pcap_freealldevs(alldevs);
					return 0;
				}
        	}
		}
	}

	dprintf(2, "No non-loopback interface found.\n");
	return -1;
}