// have 4 file descriptors to experiment with the select function call
// if web request's file descriptor (a socket) is reading, write back to it after forking
// if keyboard gives a read request, write to screen with it.  
// this will be the first web server on the planet to read from both the keyboard and the web!!
// TODO: figure out how to make this thing stop.  Doesn't respond to ctrl-c or ctrl-d i can only suspend it.
// with the code from web_server.c from     http://www.iro.umontreal.ca/~cotema/ift6815/web_server.c
//  Copyright (C) 2003 by Martin Cote
#include <termios.h>
#include <assert.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <sys/types.h>
#include <unistd.h>

#define BUF_SIZE 1024

int debug = 0;

void dump_fds(char *name, fd_set *set, int max_fd)
{
   int i;

   if(!debug) return;

   fprintf(stderr, "%s:", name);
   for(i=0; i<max_fd; i++) {
      if(FD_ISSET(i, set)) { 
         fprintf(stderr, "%d,", i);
      }
   }
   fprintf(stderr, "\n");

}

int main(int argc, char ** argv)
{
  char buf[BUF_SIZE+1];
  int sock0;
  int http_fd;
      struct sockaddr client;
  struct sockaddr_in addr;
  sock0 = socket(PF_INET, SOCK_STREAM, 0);
  int port;
   int keyboard;
   int screen;
   // char c;
   int rc;
   // struct termios tio;  
      fd_set readfds;
      fd_set writefds;
      // fd_set exceptfds;
      struct timeval tv;
      int max_fd;

      /* inbound and outbound keep track of whether we have a character */
      /* already read which needs to be sent in that direction */
      /* the _char variables are the data buffer */
      int outbound;
      char outbound_char;
      int inbound;
      char inbound_char;


  if (argc != 2)
    {
      printf("Utilisation: ./select_test <port>");
      return 0;
    }
  port = atoi(argv[1]);

/* set up the 2 local file descriptors    */

   keyboard = open("/dev/tty",O_RDONLY| O_NONBLOCK);
   assert(keyboard>=0);
   screen   = open("/dev/tty",O_WRONLY| O_NONBLOCK);
   assert(screen>=0);
	assert(sock0)>=0);

/* set up web file descriptor    */

  addr.sin_family = PF_INET;
  addr.sin_port = htons(port);
  addr.sin_addr.s_addr = htonl(INADDR_ANY);
 
 

   if(debug) {
     fprintf(stderr, "keyboard=%d\n",keyboard);
     fprintf(stderr, "screen=%d\n",screen);
     fprintf(stderr, "http_fd=%d\n",http_fd);
   }

	 FD_ZERO(&writefds);
	 FD_ZERO(&readfds);

	 max_fd = 0;
	 if(screen > max_fd)     max_fd=screen;
	 if(keyboard > max_fd)   max_fd=keyboard;
	 if(http_fd > max_fd)     max_fd=http_fd;
         max_fd++;  // first arg to select has max fd +1
         if(debug) fprintf(stderr, "max_fd=%d\n",max_fd);

	 tv.tv_sec = 10;  // sleep(10);
	 tv.tv_usec = 0;

         dump_fds("read in", &readfds, max_fd);
         dump_fds("write in", &writefds, max_fd);

	 rc= select(max_fd, &readfds, &writefds, NULL, &tv);
         if(rc==0) continue;  /* timeout */

         dump_fds("read out", &readfds, max_fd);
         dump_fds("write out", &writefds, max_fd);


	 if(FD_ISSET(keyboard, &readfds)) {
	    rc=read(keyboard,&outbound_char,1);
            if(debug) fprintf(stderr, "\nreading outbound=%d\n",outbound_char);
	    if(rc==1) outbound=1;
            if(outbound == 3) exit(0);
	 }

	 if(FD_ISSET(http_fd, &readfds)) {
	    rc=read(http_fd,&inbound_char,1);
            if(debug) fprintf(stderr, "\nreading inbound=%d\n",inbound_char);
	    if(rc==1) outbound=1;
	 }

	 if(FD_ISSET(screen, &writefds)) {
            if(debug) fprintf(stderr, "\nwriting inbound\n");
	    rc=write(screen,&inbound_char,1);
	    if(rc==1) outbound=1;
	 }

	 if(FD_ISSET(sock0, &writefds)) {
            if(debug) fprintf(stderr, "\nwriting outbound\n");
          // printf("Accepting connections on port %d\n", port);
       
	bind(sock0, (struct sockaddr*)&addr, sizeof(addr));
	listen(sock0, 5);
	int client_len = sizeof(client);
	http_fd = accept(sock0, &client, &client_len);
	if (fork() == 0)  // fork child and handle request in the chile
        {
		close(sock0);
		read(http_fd, buf, BUF_SIZE);
		char * header = "Content-type=text/html\n\n<html><title>IFT6815</title><body><h1>IFT6815 web server</h1><h3><a href=\"http://www.sirfsup.com/languages/c/unix_c/select/web_server.c\">I put it here</a></h3></body></html>";
		char c = 'z';
		write(http_fd, header, strlen(header));
		write(http_fd, z, 1);
		char * screen_out = "Ecriture?\n";
		write(screen, screen_out, strlen(screen_out));
        }
	wait();


      }
          close(http_fd);
	exit(0);

}