/*
  This file is part of TALER
  Copyright (C) 2014, 2015, 2016 GNUnet e.V. and INRIA

  TALER is free software; you can redistribute it and/or modify it under the
  terms of the GNU Lesser General Public License as published by the Free Software
  Foundation; either version 2.1, or (at your option) any later version.

  TALER 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 Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License along with
  TALER; see the file COPYING.LGPL.  If not, If not, see <http://www.gnu.org/licenses/>
*/
/**
 * @file src/benchmark/taler-exchange-benchmark.c
 * @brief exchange's benchmark
 * @author Marcello Stanisci
 */
#include "platform.h"
#include <taler/taler_util.h>
#include <taler/taler_signatures.h>
#include <taler/taler_exchange_service.h>
#include <taler/taler_json_lib.h>
#include <gnunet/gnunet_util_lib.h>
#include <gnunet/gnunet_curl_lib.h>
#include <microhttpd.h>

/**
 * How many coins the benchmark should operate on
 */
static unsigned int pool_size = 100000;

/**
 * Context for running the #ctx's event loop.
 */
static struct GNUNET_CURL_RescheduleContext *rc;

/**
 * Benchmark's task
 */
struct GNUNET_SCHEDULER_Task *benchmark_task;

/**
 * Main execution context for the main loop of the exchange.
 */
static struct GNUNET_CURL_Context *ctx;

/**
 * Handle to access the exchange.
 */
static struct TALER_EXCHANGE_Handle *exchange;

/**
 * URI under which the exchange is reachable during the benchmark.
 */
#define EXCHANGE_URI "http://localhost:8081"

/**
 * Run the main interpreter loop that performs exchange operations.
 *
 * @param cls closure for benchmark_run()
 */
static void
benchmark_run (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_INFO, "benchmark_run() invoked\n");
  GNUNET_log (GNUNET_ERROR_TYPE_INFO, "gotten pool_size of %d\n", pool_size);

  /**
   * 1 Pool's size as an option: DONE, TESTED
   * 2 Connection to the exchange: DONE, TESTED
   * 3 Allocation of large enough memory
   * 4 Withdraw
   */
}

/**
 * Functions of this type are called to provide the retrieved signing and
 * denomination keys of the exchange.  No TALER_EXCHANGE_*() functions should be called
 * in this callback.
 *
 * @param cls closure
 * @param keys information about keys of the exchange
 */
static void
cert_cb (void *cls,
         const struct TALER_EXCHANGE_Keys *keys)
{
  /* check that keys is OK */
#define ERR(cond) do { if(!(cond)) break; GNUNET_break (0); GNUNET_SCHEDULER_shutdown(); return; } while (0)
  ERR (NULL == keys);
  ERR (0 == keys->num_sign_keys);
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Read %u signing keys\n",
              keys->num_sign_keys);
  ERR (0 == keys->num_denom_keys);
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Read %u denomination keys\n",
              keys->num_denom_keys);
#undef ERR

  /* run actual tests via interpreter-loop */
  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
	      "Certificate callback invoked, invoking benchmark_run()\n");
  benchmark_task = GNUNET_SCHEDULER_add_now (&benchmark_run,
                                             NULL);
}

/**
 * Function run when the test terminates (good or bad).
 * Cleans up our state.
 *
 * @param cls the interpreter state.
 */
static void
do_shutdown (void *cls)
{
  if (NULL != exchange)
  {
    TALER_EXCHANGE_disconnect (exchange);
    exchange = NULL;
  }
  if (NULL != ctx)
  {
    GNUNET_CURL_fini (ctx);
    ctx = NULL;
  }
  if (NULL != rc)
  {
    GNUNET_CURL_gnunet_rc_destroy (rc);
    rc = NULL;
  }
}

/**
 * Main function that will be run by the scheduler.
 *
 * @param cls closure
 */
static void
run (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_INFO, "running run()\n");
  ctx = GNUNET_CURL_init (&GNUNET_CURL_gnunet_scheduler_reschedule,
                          &rc);
  GNUNET_assert (NULL != ctx);
  rc = GNUNET_CURL_gnunet_rc_create (ctx);
  exchange = TALER_EXCHANGE_connect (ctx,
                                     EXCHANGE_URI,
                                     &cert_cb, NULL,
                                     TALER_EXCHANGE_OPTION_END);
  GNUNET_assert (NULL != exchange);
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "connected to exchange\n");
  GNUNET_SCHEDULER_add_shutdown (&do_shutdown, NULL);
}

int
main (int argc,
      char * const *argv)
{

  GNUNET_log_setup ("taler-exchange-benchmark",
                    "WARNING",
                    NULL);
  const struct GNUNET_GETOPT_CommandLineOption options[] = {
    {'s', "pool-size", NULL,
     "How many coins this benchmark should instantiate", GNUNET_YES,
     &GNUNET_GETOPT_set_uint, &pool_size}
    };

  GNUNET_assert (GNUNET_SYSERR !=
                   GNUNET_GETOPT_run ("taler-exchange-benchmark",
                                      options, argc, argv));
  GNUNET_SCHEDULER_run (&run, NULL);
}