#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h> // unix standard (for close)

#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>

// program for connecting to a time service port (the daytime service)
// supported by: time.nist.gov for instance
//  see complete list at: http://tf.nist.gov/tf-cgi/servers.cgi#

// 
//      int getaddrinfo(const char *hostname, const char *servname,
// 	 const struct addrinfo *hints, struct addrinfo **res);
// 
//     struct addrinfo {
//	     int ai_flags;	     /* input flags */
//	     int ai_family;	     /* protocol family for socket */
//	     int ai_socktype;	     /* socket type */
//	     int ai_protocol;	     /* protocol for socket */
//	     socklen_t ai_addrlen;   /* length of socket-address */
//	     struct sockaddr *ai_addr; /* socket-address for socket */
//	     char *ai_canonname;     /* canonical name for service location */
//	     struct addrinfo *ai_next; /* pointer to next in list */
//     };
//
// ----
// 
#include <sys/socket.h>
// 
//      ssize_t send(int socket, const void *buffer, size_t length, int flags);
// 
// ----
// 
#include <sys/socket.h>
//
//     int socket(int domain, int type, int protocol);

int main(int argc, char *argv[])
{
    char *host;
    struct hostent *hostinfo;
    struct servent *servinfo;
    int fd ; // The socket descripter

    int status;
    struct sockaddr_in add_info;       // The struct that getaddrinfo() fills up with data.

    // set up the host as the localhost
    if (argc == 1) {
        host = (char *)"localhost";
    }
    else {
        host = argv[1];
    }
    printf("Go to host: %s\n", host);

    // get hostinfo
    //
    //    struct hosten {
    //            tchar  *h_name;           /* official name f host */
    //            char **h_aliases;         /* alias list */
    //            int    h_addrtype;        /* host address type */
    //            int    h_length;          /* length of address */
    //            char **h_addr_list;       /* list of addresses */
    //        }
    hostinfo = gethostbyname(host);
    if (hostinfo==NULL) {
        printf("ERROR(gethostbyname): failed to find host %s\n", host);
        exit(1);
    }
    printf("Got host info for: %s\n", hostinfo->h_name);

    // 
    //    structse rvent {
    //        char  *s_name;       /* official service name */
    //        char **s_aliases;    /* alias list */
    //        int    s_port;       /* port number */
    //        char  *s_proto;      /* protocol to use */
    //    }
    servinfo = getservbyname("daytime", "tcp");
    if (servinfo==NULL) {
        perror("ERROR(getservbyname): no daytime tcp service.\n");
        exit(1);
    }

    printf("Got %s service port: %d\n", servinfo->s_name, servinfo->s_port);

    // getaddrinfo returns 0 on success, or some other value when an error occured.
    // (translated into human readable text by the gai_gai_strerror function).
    //  if (status != 0)  std::cout << "getaddrinfo error" << gai_strerror(status) ;
    fd = socket(AF_INET, SOCK_STREAM, 0);
    if (fd==-1) {
        printf("ERROR(socket): socket call failed.\n");
        perror("xxx");
    }
    else {
        printf("made socket\n");
    }

    add_info.sin_family = AF_INET;
    add_info.sin_port = servinfo->s_port;
    add_info.sin_addr = *(struct in_addr *)*hostinfo->h_addr_list;

    // connect
    printf("Try to connect to fd: %d\n", fd);
    status = connect(fd, (const struct sockaddr *)&add_info, sizeof(add_info));
    if (status) {
        printf("ERROR(connect): %d\n", status);
        perror("connect");
    }
    else {
        printf("connected\n");
    }

    int bytes;
    int buffsize = 65536;
    char buff[buffsize];

    bytes = read(fd, buff, buffsize-1);
    buff[bytes] = '\0';

    printf("Read %d bytes from %s: %s\n", bytes, hostinfo->h_name, buff);

    close(fd);

    return 0;
}