/* virt-hostinfo
 * Copyright (C) 2009 Red Hat Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include <apr_general.h>
#include <apr_network_io.h>
#include <apr_getopt.h>
#include <apr_strings.h>
#include <apr_thread_proc.h>
#include <apr_poll.h>
#include <apr_portable.h>

#include "hostinfod.h"

static void main_loop (void);
static void set_reread_socket_dir (const apr_pollfd_t *);
static void do_reread_socket_dir (void);

typedef void (*poll_callback) (const apr_pollfd_t *);

const char *conf_file = DEFAULT_CONF_FILE;
char *socket_dir = NULL;
char *guests_file = NULL;

int verbose = 0;
int verbose_set_on_cmdline = 0;
int foreground = 0;
int foreground_set_on_cmdline = 0;

int messages_to_stderr = 1;

static int reread_socket_dir = 1;
static int quit = 0;

apr_pool_t *pool = NULL;
static apr_pollset_t *set;

static void
usage (void)
{
  printf ("hostinfod (virt-hostinfo daemon)\n"
	  "Copyright (C) 2009 Red Hat Inc.\n"
	  "\n"
	  "Usage:\n"
	  "  hostinfod [--options]\n"
	  "\n"
	  "Options:\n"
	  "  --help           Display full usage\n"
	  "  -c file | --config file\n"
	  "                   Configuration file (default: %s)\n"
	  "  -f | --foreground\n"
	  "                   Run in the foreground (don't fork)\n"
	  "  -v               Enable verbose messages (sent to syslog, and to\n"
	  "                     stderr if -d option is given)\n",
	  DEFAULT_CONF_FILE);
}

int
main (int argc, char *argv[])
{
  static const apr_getopt_option_t options[] = {
    { "config", 'c', TRUE, "configuration file" },
    { "foreground", 'f', FALSE, "run in foreground (don't fork)" },
    { "verbose", 'v', FALSE, "enable verbose messages" },
    { "help", '?', FALSE, "display help" },
    { NULL, 0, 0, NULL },
  };
  apr_status_t r;
  apr_getopt_t *opt;
  int c;
  const char *optarg;

  apr_initialize ();
  apr_pool_create (&pool, NULL);

  apr_getopt_init (&opt, pool, argc, argv);

  init_syslog ();

  socket_dir = apr_pstrdup (pool, DEFAULT_SOCKET_DIR);
  guests_file = apr_pstrdup (pool, DEFAULT_GUESTS_FILE);

  /* Command line. */
  while ((r = apr_getopt_long (opt, options, &c, &optarg)) == APR_SUCCESS) {
    switch (c) {
    case 'c':
      conf_file = optarg;
      /* If the user is specifying this on the command line, then
       * it should exist.  They may have typo'd the name.
       */
      if (access (conf_file, R_OK) == -1) {
	perrorf ("%s", conf_file);
	exit (1);
      }
      break;
    case 'f':
      foreground = 1;
      foreground_set_on_cmdline = 1;
      break;
    case 'v':
      verbose = 1;
      verbose_set_on_cmdline = 1;
      break;
    case '?':
      usage ();
      exit (0);
    default:
      abort ();
    }
  }
  if (r != APR_EOF) {
    fprintf (stderr, "%s: unknown command line option\n", argv[0]);
    exit (1);
  }

  /* Read the config file. */
  read_main_conf_file ();

  /* Monitor the socket directory. */
  monitor_socket_dir ();

  /* Create the initial pollset, just containing inotify socket. */
  r = apr_pollset_create (&set, 1024 /* ? */, pool, 0);
  if (r != APR_SUCCESS) {
    paprerror (r, "apr_pollset_create");
    exit (1);
  }
  apr_socket_t *tsock;
  r = apr_os_sock_put (&tsock, &sockets_inotify_fd, pool);
  if (r != APR_SUCCESS) {
    paprerror (r, "apr_os_sock_put");
    exit (1);
  }
  apr_pollfd_t *tpollfd = apr_palloc (pool, sizeof *tpollfd);
  tpollfd->p = pool;
  tpollfd->desc_type = APR_POLL_SOCKET;
  tpollfd->reqevents = APR_POLLIN;
  tpollfd->rtnevents = 0;
  tpollfd->desc.s = tsock;
  tpollfd->client_data = set_reread_socket_dir;
  r = apr_pollset_add (set, tpollfd);
  if (r != APR_SUCCESS) {
    paprerror (r, "apr_pollset_add");
    exit (1);
  }

  /* Daemonize. */
  chdir ("/");
  if (!foreground) {
    apr_proc_detach (1);

    /* After we detach from the terminal, all further messages
     * should just go to syslog.
     */
    messages_to_stderr = 0;
  }

  message (PACKAGE_STRING);
  main_loop ();

  apr_terminate ();
  return 0;
}

static void
main_loop (void)
{
  apr_status_t r;
  apr_int32_t numdescs;
  const apr_pollfd_t *descs;
  int i;

  while (!quit) {
    /* A socket has appeared or disappeared from the socket directory. */
    if (reread_socket_dir) {
      do_reread_socket_dir ();
      reread_socket_dir = 0;
    }

    /* Poll. */
    r = apr_pollset_poll (set, 0, &numdescs, &descs);
    if (r != APR_SUCCESS) {
      paprerror (r, "apr_pollset_poll");
      exit (1);
    }

    /* Perform the callbacks. */
    for (i = 0; i < numdescs; ++i) {
      poll_callback callback;

      callback = descs[i].client_data;
      callback (&descs[i]);
    }
  }
}

static void
set_reread_socket_dir (const apr_pollfd_t *_)
{
  reread_socket_dir = 1;
}

static void
do_reread_socket_dir (void)
{
  char buf[256];

  debug ("reading socket directory");

  /* Discard anything which appears on the inotify socket.  We will
   * reread the whole directory each time.
   */
  while (read (sockets_inotify_fd, buf, sizeof buf) > 0)
    ;











}