/* -*- c-basic-offset: 4 -*- */

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdarg.h>
#include <errno.h>
#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>

#include "net.h"

#define MAX_CLIENTS 2
#define SRV_FDS 1

int servsock;
struct pollfd pollfds[SRV_FDS+MAX_CLIENTS];
int nclients = 0;

FILE *net_side[2];

int
errx(int eval, const char *fmt, ...) {
    va_list ap;
    va_start(ap, fmt);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
    exit(eval);
}

void
net_server(int port) {
    struct sockaddr_in serveraddr;
    serveraddr.sin_family = AF_INET;
    serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);
    serveraddr.sin_port = htons(port);


    servsock=socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (servsock<0)
	errx(1, "socket: %s\n", strerror(errno));
    int r;
    do r=bind(servsock, (struct sockaddr *)&serveraddr, sizeof(serveraddr));
    while ((r<0) && (errno==EADDRINUSE));
    if (r < 0)
	errx(1, "bind port %d: %s\n", port, strerror(errno));
    if (listen(servsock, 10) < 0)
	errx(1, "listen: %s\n", strerror(errno));
#if 1
    // FIXME Temporary startup. Use net_poll for this later:
    printf("Waiting for connections...\n");
    for (int i=0; i<2; i++) {
	struct sockaddr_in clientaddr;
	int cfd;
	socklen_t slen;
	FILE *f;
	cfd=accept(servsock, (struct sockaddr *)&clientaddr, &slen);
	if (cfd<0)
	    errx(1, "accept: %s\n", strerror(errno));
	// FIXME log, shout, or something
	printf("client log on...\n");
	f = fdopen(cfd, "r+");
	if (!f)
	    errx(1, "fdopen: %s\n", strerror(errno));
	setlinebuf(f);
	fprintf(f, "Welcome!\n");
	if (i==0)
	    fprintf(f, "Waiting for another player...\n");
	fflush(f);
	net_side[i]=f;
    }
    net_all_printf("Starting game\n");
#else
    pollfds[0].fd=servsock;
    pollfds[0].events=POLLIN|POLLERR|POLLHUP;
    for (int i=SRV_FDS; i<(SRV_FDS+MAX_CLIENTS); i++) {
	pollfds[0].fd=-1;
	pollfds[0].events=0;
    }
#endif
}

void
net_all_flush() {
    for (int i=0; i<2; i++)
	fflush(net_side[i]);
}

void
net_all_printf(const char *fmt, ...) {
    va_list ap;
    va_start(ap, fmt);
    for (int i=0; i<2; i++)
	vfprintf(net_side[i], fmt, ap);
    va_end(ap);
}

void
net_side_printf(int side, const char *fmt, ...) {
    va_list ap;
    assert((side==0) || (side==1));
    va_start(ap, fmt);
    vfprintf(net_side[side], fmt, ap);
    va_end(ap);
}



void
net_poll() {
    int npoll;
    npoll=poll(pollfds, SRV_FDS+MAX_CLIENTS, -1);
    if (npoll<0)
	errx(1, "poll: %s", strerror(errno));
    if (pollfds[0].revents) {
	struct sockaddr_in clientaddr;
	int cfd;
	socklen_t slen;
	cfd=accept(servsock, (struct sockaddr *)&clientaddr, &slen);
	if (cfd<0)
	    errx(1, "accept: %s", strerror(errno));
	// FIXME log, shout, or something
	if (nclients>MAX_CLIENTS) {
#define STR_SERVER_FULL "Sorry, the server is full"
	    write(cfd, STR_SERVER_FULL, sizeof(STR_SERVER_FULL)-1);
	    close(cfd);
	} else {
	    int i;
	    for (i=SRV_FDS; i<(SRV_FDS+MAX_CLIENTS); i++)
		if (pollfds[i].fd==-1) break;
	    pollfds[i].fd=cfd;
	    pollfds[i].events=POLLIN|POLLERR|POLLHUP;
	    nclients++;
	}
	npoll--;
    }
    for (int i=SRV_FDS; npoll && i<(SRV_FDS+MAX_CLIENTS); i++) {
	if (pollfds[SRV_FDS+i].revents) {
	    int n;
	    char buf[100];
	    n=read(pollfds[SRV_FDS+i].fd, &buf, sizeof(buf));
	    // parse buf
	    // handle disconnections
	}
    }
}