#include <stdlib.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>
#include <unistd.h>
#define size 1024

int main()
{
        int sockfd,connfd=0,n,x=0,i,y=1,flag=0,first=0;
        double rtt,ud,time=0,temp;
        struct sockaddr_in serv_addr;
        char buffer[100];
        char packets[size],ack[100];

        serv_addr.sin_family = AF_INET;
        serv_addr.sin_port = htons(4444);
        serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");

        sockfd=socket(AF_INET, SOCK_STREAM, 0);

        if(sockfd<0)
        {
                printf("Socket creation failed\n");
                return 1;
        }

        connfd = connect(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr));

        if(connfd<0)
        {
                printf("server accept failed\n");
                return 1;
        }
        else
                printf("connection established\n");

        printf("enter RTT value: ");
        scanf("%lf",&rtt);
     printf("enter uniform delay after which each packet is sent: ");
        scanf("%lf",&ud);

        printf("enter the number of packets to be sent: ");
        scanf("%d",&n);

        printf("enter the contents of data: ");
        scanf("%s",packets);

        temp=(int)(rtt/ud);

        while(flag==0){
                buffer[0]='\0';
                int k=-1;

                for(i=1;i<=y;i++){
                        if((i==1)&&(packets[x]=='\0')){
                                flag=1;
                                goto two;
                        }
                        else if((i!=1)&&(packets[x]=='\0')){
                                flag=1;
                                goto one;
                        }
                        else{
                                if(x==0)
                                        first=1;
                                buffer[++k]=packets[x++];
                        }
                }

                one:
                buffer[++k]='\0';
                printf("\nsending packets: %s",buffer);

                send(sockfd,buffer,strlen(buffer)+1,0);
                recv(sockfd,ack,sizeof(ack),0);

                printf("\nreceived acknowledgement: %s",ack);

                time+=rtt;

                if(first==1){
                        first=0;
                        y=temp-1;
                }
                else
                        y=temp;
        }

        two:
        send(sockfd,"exit",5,0);
        printf("\n\ntotal time taken for transmission: %lf\n",time);

        close(sockfd);
        return 0;
}