/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include "src/core/iomgr/udp_server.h"
#include "src/core/iomgr/iomgr.h"
#include <grpc/support/log.h>
#include <grpc/support/sync.h>
#include <grpc/support/time.h>
#include "test/core/util/test_config.h"

#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <unistd.h>

#define LOG_TEST(x) gpr_log(GPR_INFO, "%s", #x)

static grpc_pollset g_pollset;
static int g_number_of_reads = 0;
static int g_number_of_bytes_read = 0;

static void
on_read (int fd)
{
  char read_buffer[512];
  ssize_t byte_count;

  gpr_mu_lock (GRPC_POLLSET_MU (&g_pollset));
  byte_count = recv (fd, read_buffer, sizeof (read_buffer), 0);

  g_number_of_reads++;
  g_number_of_bytes_read += (int) byte_count;

  grpc_pollset_kick (&g_pollset, NULL);
  gpr_mu_unlock (GRPC_POLLSET_MU (&g_pollset));
}

static void
test_no_op (void)
{
  grpc_udp_server *s = grpc_udp_server_create ();
  grpc_udp_server_destroy (s, NULL, NULL);
}

static void
test_no_op_with_start (void)
{
  grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
  grpc_udp_server *s = grpc_udp_server_create ();
  LOG_TEST ("test_no_op_with_start");
  grpc_udp_server_start (s, NULL, 0, &closure_list);
  grpc_udp_server_destroy (s, NULL, NULL);
  grpc_closure_list_run (&closure_list);
}

static void
test_no_op_with_port (void)
{
  struct sockaddr_in addr;
  grpc_udp_server *s = grpc_udp_server_create ();
  LOG_TEST ("test_no_op_with_port");

  memset (&addr, 0, sizeof (addr));
  addr.sin_family = AF_INET;
  GPR_ASSERT (grpc_udp_server_add_port (s, (struct sockaddr *) &addr, sizeof (addr), on_read));

  grpc_udp_server_destroy (s, NULL, NULL);
}

static void
test_no_op_with_port_and_start (void)
{
  grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
  struct sockaddr_in addr;
  grpc_udp_server *s = grpc_udp_server_create ();
  LOG_TEST ("test_no_op_with_port_and_start");

  memset (&addr, 0, sizeof (addr));
  addr.sin_family = AF_INET;
  GPR_ASSERT (grpc_udp_server_add_port (s, (struct sockaddr *) &addr, sizeof (addr), on_read));

  grpc_udp_server_start (s, NULL, 0, &closure_list);

  grpc_udp_server_destroy (s, NULL, &closure_list);
  grpc_closure_list_run (&closure_list);
}

static void
test_receive (int number_of_clients)
{
  grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
  struct sockaddr_storage addr;
  socklen_t addr_len = sizeof (addr);
  int clifd, svrfd;
  grpc_udp_server *s = grpc_udp_server_create ();
  int i;
  int number_of_reads_before;
  gpr_timespec deadline;
  grpc_pollset *pollsets[1];
  LOG_TEST ("test_receive");
  gpr_log (GPR_INFO, "clients=%d", number_of_clients);

  g_number_of_bytes_read = 0;

  memset (&addr, 0, sizeof (addr));
  addr.ss_family = AF_INET;
  GPR_ASSERT (grpc_udp_server_add_port (s, (struct sockaddr *) &addr, addr_len, on_read));

  svrfd = grpc_udp_server_get_fd (s, 0);
  GPR_ASSERT (svrfd >= 0);
  GPR_ASSERT (getsockname (svrfd, (struct sockaddr *) &addr, &addr_len) == 0);
  GPR_ASSERT (addr_len <= sizeof (addr));

  pollsets[0] = &g_pollset;
  grpc_udp_server_start (s, pollsets, 1, &closure_list);

  gpr_mu_lock (GRPC_POLLSET_MU (&g_pollset));

  for (i = 0; i < number_of_clients; i++)
    {
      deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE (10);

      number_of_reads_before = g_number_of_reads;
      /* Create a socket, send a packet to the UDP server. */
      clifd = socket (addr.ss_family, SOCK_DGRAM, 0);
      GPR_ASSERT (clifd >= 0);
      GPR_ASSERT (connect (clifd, (struct sockaddr *) &addr, addr_len) == 0);
      GPR_ASSERT (5 == write (clifd, "hello", 5));
      while (g_number_of_reads == number_of_reads_before && gpr_time_cmp (deadline, gpr_now (deadline.clock_type)) > 0)
	{
	  grpc_pollset_worker worker;
	  grpc_pollset_work (&g_pollset, &worker, gpr_now (GPR_CLOCK_MONOTONIC), deadline, &closure_list);
	  gpr_mu_unlock (GRPC_POLLSET_MU (&g_pollset));
	  grpc_closure_list_run (&closure_list);
	  gpr_mu_lock (GRPC_POLLSET_MU (&g_pollset));
	}
      GPR_ASSERT (g_number_of_reads == number_of_reads_before + 1);
      close (clifd);
    }
  GPR_ASSERT (g_number_of_bytes_read == 5 * number_of_clients);

  gpr_mu_unlock (GRPC_POLLSET_MU (&g_pollset));

  grpc_udp_server_destroy (s, NULL, NULL);
}

static void
destroy_pollset (void *p, int success, grpc_closure_list * closure_list)
{
  grpc_pollset_destroy (p);
}

int
main (int argc, char **argv)
{
  grpc_closure destroyed;
  grpc_closure_list closure_list = GRPC_CLOSURE_LIST_INIT;
  grpc_test_init (argc, argv);
  grpc_iomgr_init ();
  grpc_pollset_init (&g_pollset);

  test_no_op ();
  test_no_op_with_start ();
  test_no_op_with_port ();
  test_no_op_with_port_and_start ();
  test_receive (1);
  test_receive (10);

  grpc_closure_init (&destroyed, destroy_pollset, &g_pollset);
  grpc_pollset_shutdown (&g_pollset, &destroyed, &closure_list);
  grpc_closure_list_run (&closure_list);
  grpc_iomgr_shutdown ();
  return 0;
}