#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <unistd.h>

typedef struct {
	int	  id;
	char *msg;
} t_client;

t_client clients[FD_SETSIZE];

char recv_buf[3000];
char send_buf[3000];

int maxfd;
int lastid = 0;
int sockfd;

fd_set main_fd, read_fd;

void append_client(int cli_fd) {
	lastid++;
	clients[cli_fd].id = lastid;
	clients[cli_fd].msg = NULL;
	FD_SET(cli_fd, &main_fd);
}

void send_all() {
	size_t len = strlen(send_buf);

	for (int i = 0; i <= maxfd; i++)
		if (FD_ISSET(i, &read_fd))
			send(i, send_buf, len, 0);
}

int send_error(void) {
	for (int i = 0; i < FD_SETSIZE; i++)
		if (FD_ISSET(i, &main_fd))
			close(i);
	close(sockfd);
	write(STDERR_FILENO, "Fatal error\n", 12);
	return (EXIT_FAILURE);
}

int main(int ac, char **av) {
	if (ac != 2) {
		write(STDERR_FILENO, "Wrong number of argument\n", 25);
		return (EXIT_FAILURE);
	}

	socklen_t		   len;
	struct sockaddr_in servaddr, cli;

	sockfd = socket(AF_INET, SOCK_STREAM, 0);
	if (sockfd == -1)
		return (send_error());

	servaddr.sin_family = AF_INET;
	servaddr.sin_addr.s_addr = htonl(2130706433); // 127.0.0.1
	servaddr.sin_port = htons(atoi(av[1]));

	if (bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) != 0)
		return (send_error());

	if (listen(sockfd, 10) != 0)
		return (send_error());

	FD_ZERO(&main_fd);
	FD_ZERO(&read_fd);
	FD_SET(sockfd, &main_fd);
	maxfd = sockfd;

	while (1) {
		read_fd = main_fd;
		int ret = select(maxfd + 1, &read_fd, NULL, NULL, NULL);
		if (ret < 0)
			return (send_error());

		for (int i = 0; i <= maxfd; i++) {
			if (FD_ISSET(i, &read_fd)) {
				if (i == sockfd) {
					len = sizeof(cli);
					int cli_fd = accept(i, (struct sockaddr *)&cli, &len);
					if (cli_fd < 0)
						return (send_error());

					if (cli_fd > maxfd)
						maxfd = cli_fd;
					append_client(cli_fd);
					bzero(send_buf, 3000);
					sprintf(send_buf, "server: client %d just arrived\n",
							lastid);
					send_all();
				} else {
				}
			}
		}
	}
}