#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/socket.h>
#include "buffer.h"
#include "net.h"
#include "util.h"

const char *progname="nc";

const char *command=NULL;
/*  buffer_t *hexbuf=NULL; */

extern char *optarg;
extern int optind, opterr, optopt;

int usage(FILE *stream, int retval)
{
	fprintf(stream, 
		"%s [options] hostname port\n"
		"        -h              Display command usage\n"
		"        -e command      Command to run instead for input/output\n"
		"        -s hostname     Use specified source address\n"
		"        -p port         Use specified source port\n"
		"        -l              Become a network listener\n"
		, progname);
	if (fflush(stream) || ferror(stream)) return 1;
	return retval;
}

void newconn_accept(listener_t *listener UNUSED, connection_t *conn)
{
	fd_t *infd=fd_stdin, *outfd=fd_stdout;

	if (command) inout_program(command, &infd, &outfd);
	
	conn->tonet=buffer_alloc();
	conn->fromnet=buffer_alloc();

	buffer_init_passthrough(conn->tonet, infd, conn->fd, 4096, NULL);
	buffer_init_passthrough(conn->fromnet, conn->fd, outfd, 4096, NULL);

	fd_set_close_on_exec(conn->fd);
	fd_set_close_on_exec(infd);
	fd_set_close_on_exec(outfd);
	fd_set_nonblock(conn->fd);
	fd_set_nonblock(infd);
	fd_set_nonblock(outfd);
}

void newconn_connected(connection_t *conn)
{
	fd_t *infd=fd_stdin, *outfd=fd_stdout;

	if (command) inout_program(command, &infd, &outfd);
	
	conn->tonet=buffer_alloc();
	conn->fromnet=buffer_alloc();

	buffer_init_passthrough(conn->tonet, infd, conn->fd, 4096, NULL);
	buffer_init_passthrough(conn->fromnet, conn->fd, outfd, 4096, NULL);

	fd_set_close_on_exec(infd);
	fd_set_close_on_exec(outfd);
	fd_set_nonblock(conn->fd);
	fd_set_nonblock(infd);
	fd_set_nonblock(outfd);
}

int main(int argc, char *argv[])
{
	char c;
/*  	char *hexfile=NULL; */
	char *shost=NULL, *dhost=NULL;
	int listener=0;
	unsigned short sport=0, dport=0;

	if (argc) setprogname(argv[0]);
	fd_prog_init();

	while ((c=getopt(argc, argv, "e:hp:ls:"))!=-1) switch(c)
	{
	case '?':
	case ':':
		die("Error parsing command line - try `%s -h'\n", progname);
	case 'e':
		command=optarg;
		break;
	case 'p':
		if (getport(optarg, &sport))
			die("Error parsing source port: %s\n", 
				strerror(errno));
		break;
	case 'h':
		return usage(stdout, 0);
	case 'l':
		listener=1;
		break;
/*  	case 'o': */
/*  		hexfile=optarg; */
/*  		break; */
	case 's':
		shost=optarg;
		break;
	default:
		die_hard("BUG! getopt returned %i (%c)\n", c, c);
	}
	if (optind<argc)
		dhost=argv[optind++];
	if (optind<argc)
	{
		if (getport(argv[optind++], &dport))
			die("Error parsing port: %s\n", 
				strerror(errno));
	}
	if (optind<argc) die("Superfluous arguments\n");

	if (signal(SIGPIPE, SIG_IGN)==SIG_ERR)
		die("signal: %s\n", strerror(errno));

/*   	if (hexfile) */
/*  	{ */
/*  		int fd; */
/*  		fd_t *hexfd=fd_alloc(); */
/*  		if ((fd=creat(hexfile, 0666))==-1) */
/*  			die("creat %s: %s\n", hexfile, strerror(errno)); */
/*  		fd_init(hexfd, fd, 0, 1, hexfile); */
/*  		fd_set_nonblock(hexfd); */
/*  		hexbuf=buffer_alloc(); */
/*  		buffer_init_outgoing(hexbuf, hexfd, 4096, NULL); */
/*  	} */

	if (listener)
	{
		listener_t **listeners; 
		int listenernum;
		int i;

		if (dhost || dport) 
			die("Destination address/port is meaningless "
				"for a network listener\n");
		listener_create(shost, sport, newconn_accept, 
			&listeners, &listenernum);
		for (i=0; i<listenernum; i++)
			fd_set_close_on_exec(listeners[i]->fd);
	}
	else
	{
		connection_create(shost, sport, dhost, dport, 
			newconn_connected);
	}
		
	while (1)
	{
		int maxfd=-1;
		fd_set rfds, wfds;
		FD_ZERO(&rfds);
		FD_ZERO(&wfds);
		fd_all_preselect(&maxfd, &rfds, &wfds);
		if (maxfd==-1) break;
		select(maxfd+1, &rfds, &wfds, NULL, NULL);
		fd_all_postselect(&rfds, &wfds);
	}
	return 0;
}