#include "../rasperf.h"
#include<stdio.h>
#include<stdlib.h>
#include<arpa/inet.h>
#include<sys/types.h>
#include<sys/wait.h>
#include<sys/socket.h>
#include<netdb.h>
#include<string.h>

//Macro definitions
#define handle_error(msg) \
    do { perror(msg); exit(1);} while(0);
#define LISTEN_BACKLOG 50

int main(int argc, char*argv[])
{   
    int socket_fd, rc;
    float setup_delta, close_delta;
    if(argc<1){
        handle_error("<usage>:tcp_server");
    }
    //Retrieve the protocol number mapping 
    //from /etc/protocols file
    struct protoent *proto_entry;
    proto_entry = getprotobyname("tcp");
    
    //Open an socket end-point for this TCP Server
    socket_fd = socket(AF_INET, SOCK_STREAM, proto_entry->p_proto);
    if(socket_fd == -1){
        handle_error("Socket descriptor creation failed");
    }

    //My address information to bind to
    struct sockaddr_in sock_addr;
    memset(&sock_addr, 0, sizeof(struct sockaddr));
    sock_addr.sin_family = AF_INET;
    sock_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    sock_addr.sin_port = htons(8000);


    rc = bind(socket_fd, (struct sockaddr*)&sock_addr, sizeof(sock_addr)); 
    if(rc == -1){
        handle_error("Bind failure");
    }
    rc = listen(socket_fd, LISTEN_BACKLOG); 
    if(rc == -1){
        handle_error(" Listen Error");
    }

    time starttime, endtime;

    //accept incoming connections
    int connfd, i, pid, addr_size = sizeof(struct sockaddr);
    for(i=1;i<=1000;i++)
    {
        //getTime(starttime);
        printf("Accept Connection\n");
        //waitpid(WAIT_ANY, NULL, WNOHANG);
        connfd = accept(socket_fd, (struct sockaddr *)NULL, NULL);
        /*The end calculated here would have missed SYN time
        from the client. And so we have to add one 
        packet worth round trip time in the overhead*/
        //getTime(endtime);
        if( connfd == -1){
            handle_error("Accept failed");
        }    
        //setup_delta+=diff(endtime,starttime);
        if(pid = fork() == 0){
            close(socket_fd);
            close(connfd);
            printf("Connection %d closed in Child\n",i);
            //close_delta=diff(endtime, starttime);
            //printf("Connection Termination %f", close_delta + RTT);
            exit(0);
        } 
        close(connfd);
    }   
    //getTime(starttime);
    close(socket_fd);
    //getTime(endtime);

    //Calculate connection overhead server side
    //setup_delta+=diff(endtime,starttime);
    //printf("Connection Overhead:Setup =%f us\n", (setup_delta+ RTT*600)/600);

    return 0;
}