#include<sys/socket.h>
#include<sys/types.h>
#include<netinet/ip.h>
#include<arpa/inet.h>
#include<stdio.h>
#include<unistd.h>
#include<signal.h>
#include<stdlib.h>
#include<string.h>

int main(int argc, char ** argv){
	struct sockaddr_in sad;
	sad.sin_port = htons(5143);
	sad.sin_addr.s_addr = INADDR_ANY;
	sad.sin_family = AF_INET;

	int skt = socket(AF_INET, SOCK_DGRAM, 0); // Step 1
	if(skt == -1){
		perror("socket");
		return 1;
	}
	if( bind(skt, (struct sockaddr*)(&sad), sizeof(struct sockaddr_in)) ){ // step 2
		perror("bind");
		return 1;
	}
	char buffer[2048];
	while(1){
		struct sockaddr_in client_address;
		socklen_t address_size = sizeof(struct sockaddr_in);
		size_t readlen = recvfrom(skt, buffer, 2047, 0, (struct sockaddr*)&client_address, &address_size);
		buffer[readlen-1] = 0;
		printf("Recieved %s ");
		printf("from address %s\n", inet_ntoa(client_address.sin_addr));
		sprintf(buffer, "Received your message of %d bytes\n", readlen);
		sendto(skt, buffer, strlen(buffer), 0, (struct sockaddr*)&client_address, address_size);
		sleep(2);
		sprintf(buffer, "It's been 2 seconds.  Are you still there?");
		ssize_t sendlen = sendto(skt, buffer, strlen(buffer), 0, (struct sockaddr*)&client_address, address_size);
		printf("Sent %d bytes\n", sendlen);

	}
	
	return 0;
}