/*
 *
 * Copyright 2015 gRPC authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

#include "src/core/lib/iomgr/port.h"

// This test won't work except with posix sockets enabled
#ifdef GRPC_POSIX_SOCKET

#include "src/core/lib/iomgr/udp_server.h"

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

#include <grpc/grpc.h>
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/sync.h>
#include <grpc/support/time.h>
#include <grpc/support/useful.h>

#include "src/core/lib/channel/channel_args.h"
#include "src/core/lib/iomgr/ev_posix.h"
#include "src/core/lib/iomgr/iomgr.h"
#include "src/core/lib/iomgr/socket_factory_posix.h"
#include "test/core/util/test_config.h"

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

static grpc_pollset *g_pollset;
static gpr_mu *g_mu;
static int g_number_of_reads = 0;
static int g_number_of_writes = 0;
static int g_number_of_bytes_read = 0;
static int g_number_of_orphan_calls = 0;

static void on_read(grpc_exec_ctx *exec_ctx, grpc_fd *emfd, void *user_data) {
  char read_buffer[512];
  ssize_t byte_count;

  gpr_mu_lock(g_mu);
  byte_count =
      recv(grpc_fd_wrapped_fd(emfd), read_buffer, sizeof(read_buffer), 0);

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

  GPR_ASSERT(
      GRPC_LOG_IF_ERROR("pollset_kick", grpc_pollset_kick(g_pollset, NULL)));
  gpr_mu_unlock(g_mu);
}

static void on_write(grpc_exec_ctx *exec_ctx, grpc_fd *emfd, void *user_data) {
  gpr_mu_lock(g_mu);
  g_number_of_writes++;

  GPR_ASSERT(
      GRPC_LOG_IF_ERROR("pollset_kick", grpc_pollset_kick(g_pollset, NULL)));
  gpr_mu_unlock(g_mu);
}

static void on_fd_orphaned(grpc_exec_ctx *exec_ctx, grpc_fd *emfd,
                           grpc_closure *closure, void *user_data) {
  gpr_log(GPR_INFO, "gRPC FD about to be orphaned: %d",
          grpc_fd_wrapped_fd(emfd));
  g_number_of_orphan_calls++;
}

struct test_socket_factory {
  grpc_socket_factory base;
  int number_of_socket_calls;
  int number_of_bind_calls;
};
typedef struct test_socket_factory test_socket_factory;

static int test_socket_factory_socket(grpc_socket_factory *factory, int domain,
                                      int type, int protocol) {
  test_socket_factory *f = (test_socket_factory *)factory;
  f->number_of_socket_calls++;
  return socket(domain, type, protocol);
}

static int test_socket_factory_bind(grpc_socket_factory *factory, int sockfd,
                                    const grpc_resolved_address *addr) {
  test_socket_factory *f = (test_socket_factory *)factory;
  f->number_of_bind_calls++;
  return bind(sockfd, (struct sockaddr *)addr->addr, (socklen_t)addr->len);
}

static int test_socket_factory_compare(grpc_socket_factory *a,
                                       grpc_socket_factory *b) {
  return GPR_ICMP(a, b);
}

static void test_socket_factory_destroy(grpc_socket_factory *factory) {
  test_socket_factory *f = (test_socket_factory *)factory;
  gpr_free(f);
}

static const grpc_socket_factory_vtable test_socket_factory_vtable = {
    test_socket_factory_socket, test_socket_factory_bind,
    test_socket_factory_compare, test_socket_factory_destroy};

static test_socket_factory *test_socket_factory_create(void) {
  test_socket_factory *factory = gpr_malloc(sizeof(test_socket_factory));
  grpc_socket_factory_init(&factory->base, &test_socket_factory_vtable);
  factory->number_of_socket_calls = 0;
  factory->number_of_bind_calls = 0;
  return factory;
}

static void test_no_op(void) {
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_udp_server *s = grpc_udp_server_create(NULL);
  grpc_udp_server_destroy(&exec_ctx, s, NULL);
  grpc_exec_ctx_finish(&exec_ctx);
}

static void test_no_op_with_start(void) {
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_udp_server *s = grpc_udp_server_create(NULL);
  LOG_TEST("test_no_op_with_start");
  grpc_udp_server_start(&exec_ctx, s, NULL, 0, NULL);
  grpc_udp_server_destroy(&exec_ctx, s, NULL);
  grpc_exec_ctx_finish(&exec_ctx);
}

static void test_no_op_with_port(void) {
  g_number_of_orphan_calls = 0;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_resolved_address resolved_addr;
  struct sockaddr_in *addr = (struct sockaddr_in *)resolved_addr.addr;
  grpc_udp_server *s = grpc_udp_server_create(NULL);
  LOG_TEST("test_no_op_with_port");

  memset(&resolved_addr, 0, sizeof(resolved_addr));
  resolved_addr.len = sizeof(struct sockaddr_in);
  addr->sin_family = AF_INET;
  GPR_ASSERT(grpc_udp_server_add_port(s, &resolved_addr, on_read, on_write,
                                      on_fd_orphaned));

  grpc_udp_server_destroy(&exec_ctx, s, NULL);
  grpc_exec_ctx_finish(&exec_ctx);

  /* The server had a single FD, which should have been orphaned. */
  GPR_ASSERT(g_number_of_orphan_calls == 1);
}

static void test_no_op_with_port_and_socket_factory(void) {
  g_number_of_orphan_calls = 0;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_resolved_address resolved_addr;
  struct sockaddr_in *addr = (struct sockaddr_in *)resolved_addr.addr;

  test_socket_factory *socket_factory = test_socket_factory_create();
  grpc_arg socket_factory_arg =
      grpc_socket_factory_to_arg(&socket_factory->base);
  grpc_channel_args *channel_args =
      grpc_channel_args_copy_and_add(NULL, &socket_factory_arg, 1);
  grpc_udp_server *s = grpc_udp_server_create(channel_args);
  grpc_channel_args_destroy(&exec_ctx, channel_args);

  LOG_TEST("test_no_op_with_port_and_socket_factory");

  memset(&resolved_addr, 0, sizeof(resolved_addr));
  resolved_addr.len = sizeof(struct sockaddr_in);
  addr->sin_family = AF_INET;
  GPR_ASSERT(grpc_udp_server_add_port(s, &resolved_addr, on_read, on_write,
                                      on_fd_orphaned));
  GPR_ASSERT(socket_factory->number_of_socket_calls == 1);
  GPR_ASSERT(socket_factory->number_of_bind_calls == 1);

  grpc_udp_server_destroy(&exec_ctx, s, NULL);
  grpc_exec_ctx_finish(&exec_ctx);
  grpc_socket_factory_unref(&socket_factory->base);

  /* The server had a single FD, which should have been orphaned. */
  GPR_ASSERT(g_number_of_orphan_calls == 1);
}

static void test_no_op_with_port_and_start(void) {
  g_number_of_orphan_calls = 0;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_resolved_address resolved_addr;
  struct sockaddr_in *addr = (struct sockaddr_in *)resolved_addr.addr;
  grpc_udp_server *s = grpc_udp_server_create(NULL);
  LOG_TEST("test_no_op_with_port_and_start");

  memset(&resolved_addr, 0, sizeof(resolved_addr));
  resolved_addr.len = sizeof(struct sockaddr_in);
  addr->sin_family = AF_INET;
  GPR_ASSERT(grpc_udp_server_add_port(s, &resolved_addr, on_read, on_write,
                                      on_fd_orphaned));

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

  grpc_udp_server_destroy(&exec_ctx, s, NULL);
  grpc_exec_ctx_finish(&exec_ctx);

  /* The server had a single FD, which is orphaned exactly once in *
   * grpc_udp_server_destroy. */
  GPR_ASSERT(g_number_of_orphan_calls == 1);
}

static void test_receive(int number_of_clients) {
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_resolved_address resolved_addr;
  struct sockaddr_storage *addr = (struct sockaddr_storage *)resolved_addr.addr;
  int clifd, svrfd;
  grpc_udp_server *s = grpc_udp_server_create(NULL);
  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;
  g_number_of_orphan_calls = 0;

  memset(&resolved_addr, 0, sizeof(resolved_addr));
  resolved_addr.len = sizeof(struct sockaddr_storage);
  addr->ss_family = AF_INET;
  GPR_ASSERT(grpc_udp_server_add_port(s, &resolved_addr, on_read, on_write,
                                      on_fd_orphaned));

  svrfd = grpc_udp_server_get_fd(s, 0);
  GPR_ASSERT(svrfd >= 0);
  GPR_ASSERT(getsockname(svrfd, (struct sockaddr *)addr,
                         (socklen_t *)&resolved_addr.len) == 0);
  GPR_ASSERT(resolved_addr.len <= sizeof(struct sockaddr_storage));

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

  gpr_mu_lock(g_mu);

  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,
                       (socklen_t)resolved_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 = NULL;
      GPR_ASSERT(GRPC_LOG_IF_ERROR(
          "pollset_work",
          grpc_pollset_work(&exec_ctx, g_pollset, &worker,
                            gpr_now(GPR_CLOCK_MONOTONIC), deadline)));
      gpr_mu_unlock(g_mu);
      grpc_exec_ctx_finish(&exec_ctx);
      gpr_mu_lock(g_mu);
    }
    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(g_mu);

  grpc_udp_server_destroy(&exec_ctx, s, NULL);
  grpc_exec_ctx_finish(&exec_ctx);

  /* The server had a single FD, which is orphaned exactly once in *
   * grpc_udp_server_destroy. */
  GPR_ASSERT(g_number_of_orphan_calls == 1);

  /* The write callback should have fired a few times. */
  GPR_ASSERT(g_number_of_writes > 0);
}

static void destroy_pollset(grpc_exec_ctx *exec_ctx, void *p,
                            grpc_error *error) {
  grpc_pollset_destroy(exec_ctx, p);
}

int main(int argc, char **argv) {
  grpc_closure destroyed;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_test_init(argc, argv);
  grpc_init();
  g_pollset = gpr_zalloc(grpc_pollset_size());
  grpc_pollset_init(g_pollset, &g_mu);

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

  GRPC_CLOSURE_INIT(&destroyed, destroy_pollset, g_pollset,
                    grpc_schedule_on_exec_ctx);
  grpc_pollset_shutdown(&exec_ctx, g_pollset, &destroyed);
  grpc_exec_ctx_finish(&exec_ctx);
  gpr_free(g_pollset);
  grpc_shutdown();
  return 0;
}

#else /* GRPC_POSIX_SOCKET */

int main(int argc, char **argv) { return 1; }

#endif /* GRPC_POSIX_SOCKET */