#include <iostream>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
#include <string.h>

using namespace std;
const int BUFFER_SIZE{1000};
const string SOCKET_PATH{"/tmp/msgServer"};

int main()  {

     int socketFD{socket(AF_UNIX,SOCK_DGRAM, 0)};

     if (socketFD == -1) {
        perror("Error socket: ");
        return 1;
     }

     struct sockaddr_un address;
     int addrLen = sizeof(struct sockaddr_un);

     memset(&address, 0, addrLen);
     address.sun_family = AF_UNIX;
     strncpy(address.sun_path, SOCKET_PATH.c_str(), sizeof(address.sun_path)-1);

     // may have an error.
     unlink(SOCKET_PATH.c_str());

     if (bind(socketFD, reinterpret_cast<struct sockaddr *>(&address),
                                                           addrLen) == -1) {
         perror("Error bind: ");
         close(socketFD);
         unlink(SOCKET_PATH.c_str());
         return 1;
     }

     bool done = false;
     size_t numBytes;
     char buffer[BUFFER_SIZE];
     struct sockaddr_un clientAddress;
     socklen_t len;

     while(not done) {
         len = addrLen;
         memset (buffer, 0, BUFFER_SIZE);

         numBytes = recvfrom (socketFD, buffer, BUFFER_SIZE, 0, 
                 reinterpret_cast<struct sockaddr *>(&clientAddress), &len);

         if (numBytes == -1)  {
            perror("Error recvfrom: "); 
            done = true;
         }

         cout << " I got " << numBytes << " bytes from " 
              << clientAddress.sun_path << " \"" << buffer << '\"' << endl;

         if (strcmp(buffer, "quit") == 0) {
            done = true;
         }

         
         if(-1 == sendto(socketFD, buffer, numBytes,0, 
                 reinterpret_cast<struct sockaddr *>(&clientAddress), len)) {
             perror("Error sendto: ");
         }
              
     } 

     cout << "Got a quit message, exiting" << endl;
     close(socketFD);
     unlink(SOCKET_PATH.c_str());
     return 0;
}