/* MehdiJassmine 2018
 * They must have read about some defaults, because it works without numerous
 * flags set
 * and they do not use all the recommended libraries,
 * I have added some comments, the key being to 'disect'  man getaddrinfo
 * /

#include "dnsaccess.h"

int main(int argc, char **argv) 
{
    /* Check command line args */
    if (argc != 2) {
        fprintf(stderr, "usage: %s <ip address/domain name>\n", argv[0]);
        exit(1);
    }

    /* CreateAndType string, and then Pull domain name from input stream */
    char* domain_name_or_address = argv[1];

    /* My mistake, here they are converting an IP address to a Domain Name */
    /* and then passing that on */
    if (check_IP_address(domain_name_or_address)){
        char* addr = domain_name_or_address;
        char hostname[1024];
        /* call their own function for this stupid option */
        get_hostname_from_addr(addr, hostname, sizeof(hostname));
        printf("hostname: %s\n", hostname);
    } else {
        char* domain_name = domain_name_or_address;

    /* Mike comment */
        /* from 'man getaddrinfo' the following code can be used to setup that
         * structure
         * memset(&hints, 0, sizeof(struct addrinfo));
         * hints.ai_family = AF_UNSPEC;     Allow IPv4 or IPv6 
         * hints.ai_socktype = SOCK_DGRAM;  Datagram socket 
         * hints.ai_flags = AI_PASSIVE;     For wildcard IP address 
         * hints.ai_protocol = 0;           Any protocol 
         * hints.ai_canonname = NULL;
         * hints.ai_addr = NULL;
         * hints.ai_next = NULL;
         */ 

        /* Their code */
        /* create the struct hints as a addrinfo type */
        struct addrinfo hints;
        memset(&hints, 0, sizeof(hints));   /* Zero hints struct */
        hints.ai_family = AF_INET;          /* Only hint set, rest must be defaults */

        /* Finds IP addresses associated to a domain name. */
        struct addrinfo* result;
        getaddrinfo(domain_name, NULL, &hints, &result);

        /* Take the returned pointed to struct, result and pull it apart */
        for(struct addrinfo* res = result; res != NULL; res = res->ai_next){
            struct sockaddr_in* sa = (struct sockaddr_in*) res->ai_addr;
            struct in_addr ip_addr = sa->sin_addr;
            char* addr = inet_ntoa(ip_addr);
            printf("address: %s\n", addr);
        }
    }
}