#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<pthread.h>
#include<string.h>

#include<vector>
using namespace std;

struct client_parameters{
	int fd;
	struct sockaddr_in address;
};

vector<int> client_fds;

void*	handle_client(void *param){
		struct client_parameters *cp = (struct client_parameters*)param;
		client_fds.push_back(cp->fd);
		printf("Connection made from address %s\n", inet_ntoa(cp->address.sin_addr));
		write(cp->fd, "Good Morning\n", 13);
		char client_message[100];
		while(1){
			memset(client_message, 0, 99);	 // Slower, but yields a clean slate, fixes null terminator problem
			ssize_t readlen = read(cp->fd, client_message, 100);
			// client_message[readlen] = 0; // Faster, since we place the null terminator right where it needs to be
			if(readlen <= 0)
				break;
			printf("Client %d sent:  %s", cp->fd, client_message);
			// We need to relay this to other clients instead
			for(auto fd : client_fds){
				if(fd != cp->fd)
					write(fd, client_message, readlen);
			}
		}
		printf("Client %d disconnected\n", cp->fd);
		// Remove from list of clients before we close
		for(int i = 0; i < client_fds.size(); i++){
			if(client_fds[i] == cp->fd){
				client_fds.erase(client_fds.begin() + i);  // Could this cause a race condition?
			}
		}
		close(cp->fd);
		free(cp);
		return 0;
}

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_STREAM, 0); // Step 1:  Make a socket
	if(skt == -1){
		perror("socket");
		return 1;
	}
	if( bind(skt, (struct sockaddr*)(&sad), sizeof(struct sockaddr_in)) ){ // Step 2:  Bind the socket to a port
		perror("bind");
		return 1;
	}
	if( listen(skt, 5) ){ // step 3
		perror("listen");
		return 1;
	}	
	while(1){
		int client_fd;
		struct sockaddr_in client_address;
		socklen_t address_size = sizeof(struct sockaddr_in);
		client_fd = accept(skt, (struct sockaddr *)(&client_address), &address_size); // step 4
		pthread_t thread_handle;
		struct client_parameters *cp = (struct client_parameters*)malloc(sizeof(struct client_parameters));
		cp->fd = client_fd;
		cp->address = client_address;
		pthread_create(&thread_handle, 0, handle_client, cp);
	}
	
	return 0;
}