#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include "err.h"

#define BUFFER_SIZE 2000
#define QUEUE_LENGTH 5
#define MAX_MENU_STR 100
#define MIN_PORT 1024
#define MAX_PORT 65535


char RESET_TERM[] = {0x1B,'c','\0'};
// IAC DO LINEMODE IAC WILL ECHO
char NEGOTIATION[] = "\377\375\042\377\373\001";

char MAIN_MENU[] = "Opcja A\n\r"
                    "Opcja B\n\r"
                    "Koniec\n\r";

char MENU_SECOND[] = "Opcja B1\n\r"
                     "Opcja B2\n\r"
                     "Wstecz\n\r";


// void menu_str(char *str, int menu_type, ) {
//   //TODO
// }


char ARR_UP[] = {27, 91, 65};
char ARR_DOWN[] = {27, 91, 66};

int main(int argc, char *argv[])
{
  int sock, msg_sock;
  struct sockaddr_in server_address;
  struct sockaddr_in client_address;
  socklen_t client_address_len;

  char buffer[BUFFER_SIZE];
  ssize_t len, snd_len;

  // checking the number of arguments
  if (argc != 2) {
    fprintf(stderr, "One argument required: port number\n");
    return 1;
  }

  // checking if given port number is in the correct range
  int port_num = argv[1];
  if (port_num <= MIN_PORT || port_num >= MAX_PORT) {
    fprintf(stderr, "Port number not in range <%d, %d>\n", MIN_PORT, MAX_PORT);
    return 1;
  }

  sock = socket(PF_INET, SOCK_STREAM, 0); // creating IPv4 TCP socket
  if (sock < 0)
    syserr("socket");
  // after socket() call; we should close(sock) on any execution path;
  // since all execution paths exit immediately, sock would be closed when program terminates

  server_address.sin_family = AF_INET; // IPv4
  server_address.sin_addr.s_addr = htonl(INADDR_ANY); // listening on all interfaces
  server_address.sin_port = htons(port_num); // listening on port port_num

  // bind the socket to a concrete address
  if (bind(sock, (struct sockaddr *) &server_address, sizeof(server_address)) < 0)
    syserr("bind");

  // switch to listening (passive open)
  if (listen(sock, QUEUE_LENGTH) < 0)
    syserr("listen");

  for (;;) {
    client_address_len = sizeof(client_address);
    // get client connection from the socket
    msg_sock = accept(sock, (struct sockaddr *) &client_address, &client_address_len);

    if (msg_sock < 0) {
      syserr("accept");
    } else {
      printf("Client has connected.\n");
    }

    // if(write(msg_sock, RESET_TERM, sizeof(RESET_TERM)) != sizeof(RESET_TERM)) {
    //   syserr("partial / failed write");
    // }

    if(write(msg_sock, NEGOTIATION, 6) != 6) {
      syserr("failed negotiation");
    }

    do {
      if(write(msg_sock, RESET_TERM, sizeof(RESET_TERM)) != sizeof(RESET_TERM)) {
        syserr("partial / failed write");
      }

      if (write(msg_sock, MAIN_MENU, sizeof(MAIN_MENU)) != sizeof(MAIN_MENU)) {
        syserr("failed menu");
      }

      len = read(msg_sock, buffer, sizeof(buffer));
      if(len == 3) {
        if(strncmp(buffer, ARR_UP, 3) == 0) {
          printf("A\n");
        } else if(strncmp(buffer, ARR_DOWN, 3) == 0) {
          printf("B\n");
        } else {
          printf("C\n");
        }
      }

      if (len < 0)
        syserr("reading from client socket");
      else {
        // printf("read from socket: %zd bytes: %.*s\n", len, (int) len, buffer);
        // snd_len = write(msg_sock, buffer, len);
        // if (snd_len != len)
        //   syserr("writing to client socket");
      }
    } while (len > 0);

    printf("Ending connection.\n");

    if (close(msg_sock) < 0)
      syserr("close");
  }

  return 0;
}