/*
     This file is part of GNUnet.
     (C) 2001, 2002, 2004, 2005, 2006, 2007, 2009 Christian Grothoff (and other contributing authors)

     GNUnet 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 3, or (at your
     option) any later version.

     GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file statistics/gnunet-statistics.c
 * @brief tool to obtain statistics
 * @author Christian Grothoff
 * @author Igor Wronsky
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_statistics_service.h"
#include "statistics.h"

#define GET_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)

/**
 * Final status code.
 */
static int ret;

/**
 * Set to subsystem that we're going to get stats for (or NULL for all).
 */
static char *subsystem;

/**
 * Set to the specific stat value that we are after (or NULL for all).
 */
static char *name;

/**
 * Make the value that is being set persistent.
 */
static int persistent;

/**
 * Watch value continuously
 */
static int watch;

/**
 * Quiet mode
 */
static int quiet;

/**
 * Remote host
 */
static char *remote_host;

/**
 * Remote host's port
 */
static unsigned long long  remote_port;

/**
 * Value to set
 */
static unsigned long long set_val;

/**
 * Set operation
 */
static int set_value;


/**
 * Callback function to process statistic values.
 *
 * @param cls closure
 * @param subsystem name of subsystem that created the statistic
 * @param name the name of the datum
 * @param value the current value
 * @param is_persistent #GNUNET_YES if the value is persistent, #GNUNET_NO if not
 * @return #GNUNET_OK to continue, #GNUNET_SYSERR to abort iteration
 */
static int
printer (void *cls,
         const char *subsystem,
         const char *name,
         uint64_t value,
         int is_persistent)
{
  struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get();
  const char * now_str;

  if (quiet == GNUNET_NO)
  {
    if (GNUNET_YES == watch)
    {
      now_str = GNUNET_STRINGS_absolute_time_to_string(now);
      FPRINTF (stdout, "%24s %s%12s %50s: %16llu \n",
               now_str,
               is_persistent ? "!" : " ",
               subsystem, _(name), (unsigned long long) value);
    }
    else
    {
      FPRINTF (stdout, "%s%12s %50s: %16llu \n",
               is_persistent ? "!" : " ",
               subsystem, _(name), (unsigned long long) value);
    }
  }
  else
    FPRINTF (stdout, "%llu\n", (unsigned long long) value);

  return GNUNET_OK;
}


/**
 * Function called last by the statistics code.
 *
 * @param cls closure
 * @param success #GNUNET_OK if statistics were
 *        successfully obtained, #GNUNET_SYSERR if not.
 */
static void
cleanup (void *cls, int success)
{

  if (success != GNUNET_OK)
  {
    if (NULL == remote_host)
      FPRINTF (stderr,
               "%s",
               _("Failed to obtain statistics.\n"));
    else
      FPRINTF (stderr,
               _("Failed to obtain statistics from host `%s:%llu'\n"),
               remote_host,
               remote_port);
    ret = 1;
  }
  GNUNET_SCHEDULER_shutdown ();
}


/**
 * Function run on shutdown to clean up.
 *
 * @param cls the statistics handle
 * @param tc scheduler context
 */
static void
shutdown_task (void *cls,
               const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct GNUNET_STATISTICS_Handle *h = cls;

  if (NULL == h)
    return;
  if ( (GNUNET_YES == watch) &&
       (NULL != subsystem) &&
       (NULL != name) )
    GNUNET_assert (GNUNET_OK ==
		   GNUNET_STATISTICS_watch_cancel (h, subsystem, name, &printer, h));
  GNUNET_STATISTICS_destroy (h, GNUNET_NO);
  h = NULL;
}


/**
 * Main task that does the actual work.
 *
 * @param cls closure with our configuration
 * @param tc schedueler context
 */
static void
main_task (void *cls,
           const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
  struct GNUNET_STATISTICS_Handle *h;

  if (set_value)
  {
    if (NULL == subsystem)
    {
      FPRINTF (stderr, "%s", _("Missing argument: subsystem \n"));
      ret = 1;
      return;
    }
    if (NULL == name)
    {
      FPRINTF (stderr, "%s", _("Missing argument: name\n"));
      ret = 1;
      return;
    }
    h = GNUNET_STATISTICS_create (subsystem, cfg);
    if (NULL == h)
    {
      ret = 1;
      return;
    }
    GNUNET_STATISTICS_set (h, name, (uint64_t) set_val, persistent);
    GNUNET_STATISTICS_destroy (h, GNUNET_YES);
    h = NULL;
    return;
  }
  if (NULL == (h = GNUNET_STATISTICS_create ("gnunet-statistics", cfg)))
  {
    ret = 1;
    return;
  }
  if (GNUNET_NO == watch)
  {
    if (NULL ==
      GNUNET_STATISTICS_get (h, subsystem, name, GET_TIMEOUT, &cleanup,
                             &printer, h))
    cleanup (h, GNUNET_SYSERR);
  }
  else
  {
    if ((NULL == subsystem) || (NULL == name))
    {
      printf (_("No subsystem or name given\n"));
      GNUNET_STATISTICS_destroy (h, GNUNET_NO);
      h = NULL;
      ret = 1;
      return;
    }
    if (GNUNET_OK != GNUNET_STATISTICS_watch (h, subsystem, name, &printer, h))
    {
      fprintf (stderr, _("Failed to initialize watch routine\n"));
      GNUNET_SCHEDULER_add_now (&shutdown_task, h);
      return;
    }
  }
  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
                                &shutdown_task, h);
}


/**
 * Function called with th test result to see if the resolver is
 * running.
 *
 * @param cls closure with our configuration
 * @param result #GNUNET_YES if the resolver is running
 */
static void
resolver_test_task (void *cls,
		    int result)
{
  struct GNUNET_CONFIGURATION_Handle *cfg = cls;

  if (GNUNET_YES != result)
   {
     FPRINTF (stderr,
	      _("Trying to connect to remote host, but service `%s' is not running\n"),
              "resolver");
     return;
   }
  /* connect to a remote host */
  if (0 == remote_port)
  {
    if (GNUNET_SYSERR ==
        GNUNET_CONFIGURATION_get_value_number (cfg, "statistics",
                                               "PORT",
                                               &remote_port))
    {
      FPRINTF (stderr,
               _("A port is required to connect to host `%s'\n"),
               remote_host);
      return;
    }
  }
  else if (65535 <= remote_port)
  {
    FPRINTF (stderr,
	     _("A port has to be between 1 and 65535 to connect to host `%s'\n"),
             remote_host);
    return;
  }

  /* Manipulate configuration */
  GNUNET_CONFIGURATION_set_value_string (cfg,
					 "statistics", "UNIXPATH", "");
  GNUNET_CONFIGURATION_set_value_string (cfg,
					 "statistics", "HOSTNAME", remote_host);
  GNUNET_CONFIGURATION_set_value_number (cfg,
					 "statistics", "PORT", remote_port);
  GNUNET_SCHEDULER_add_now (&main_task, cfg);
}


/**
 * Main function that will be run by the scheduler.
 *
 * @param cls closure
 * @param args remaining command-line arguments
 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 * @param cfg configuration
 */
static void
run (void *cls, char *const *args, const char *cfgfile,
     const struct GNUNET_CONFIGURATION_Handle *cfg)
{
  set_value = GNUNET_NO;
  if (NULL != args[0])
  {
    if (1 != SSCANF (args[0], "%llu", &set_val))
    {
      FPRINTF (stderr, _("Invalid argument `%s'\n"), args[0]);
      ret = 1;
      return;
    }
    set_value = GNUNET_YES;
  }
  if (NULL != remote_host)
    GNUNET_CLIENT_service_test ("resolver", cfg, GNUNET_TIME_UNIT_SECONDS,
				&resolver_test_task, (void *) cfg);
  else
    GNUNET_SCHEDULER_add_now (&main_task, (void *) cfg);
}


/**
 * The main function to obtain statistics in GNUnet.
 *
 * @param argc number of arguments from the command line
 * @param argv command line arguments
 * @return 0 ok, 1 on error
 */
int
main (int argc, char *const *argv)
{
  static const struct GNUNET_GETOPT_CommandLineOption options[] = {
    {'n', "name", "NAME",
     gettext_noop ("limit output to statistics for the given NAME"), 1,
     &GNUNET_GETOPT_set_string, &name},
    {'p', "persistent", NULL,
     gettext_noop ("make the value being set persistent"), 0,
     &GNUNET_GETOPT_set_one, &persistent},
    {'s', "subsystem", "SUBSYSTEM",
     gettext_noop ("limit output to the given SUBSYSTEM"), 1,
     &GNUNET_GETOPT_set_string, &subsystem},
    {'q', "quiet", NULL,
     gettext_noop ("just print the statistics value"), 0,
     &GNUNET_GETOPT_set_one, &quiet},
    {'w', "watch", NULL,
     gettext_noop ("watch value continuously"), 0,
     &GNUNET_GETOPT_set_one, &watch},
     {'r', "remote", NULL,
      gettext_noop ("connect to remote host"), 1,
      &GNUNET_GETOPT_set_string, &remote_host},
    {'o', "port", NULL,
     gettext_noop ("port for remote host"), 1,
     &GNUNET_GETOPT_set_uint, &remote_port},
    GNUNET_GETOPT_OPTION_END
  };
  remote_port = 0;
  remote_host = NULL;
  if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv))
    return 2;

  ret = (GNUNET_OK ==
	 GNUNET_PROGRAM_run (argc, argv, "gnunet-statistics [options [value]]",
			     gettext_noop
			     ("Print statistics about GNUnet operations."),
			     options, &run, NULL)) ? ret : 1;
  GNUNET_free_non_null (remote_host);
  GNUNET_free ((void*) argv);
  return ret;
}

/* end of gnunet-statistics.c */