//
// Copyright 2017 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 <string.h>

#include <functional>
#include <initializer_list>
#include <memory>
#include <string>

#include "absl/strings/str_format.h"

#include <grpc/byte_buffer.h>
#include <grpc/grpc.h>
#include <grpc/impl/propagation_bits.h>
#include <grpc/slice.h>
#include <grpc/status.h>
#include <grpc/support/log.h>
#include <grpc/support/time.h>

#include "src/core/lib/channel/channel_args.h"
#include "src/core/lib/gpr/useful.h"
#include "test/core/end2end/cq_verifier.h"
#include "test/core/end2end/end2end_tests.h"
#include "test/core/util/test_config.h"

static std::unique_ptr<CoreTestFixture> begin_test(
    const CoreTestConfiguration& config, const char* test_name,
    grpc_channel_args* client_args, grpc_channel_args* server_args) {
  gpr_log(GPR_INFO, "Running test: %s/%s", test_name, config.name);
  auto f = config.create_fixture(grpc_core::ChannelArgs::FromC(client_args),
                                 grpc_core::ChannelArgs::FromC(server_args));
  f->InitServer(grpc_core::ChannelArgs::FromC(server_args));
  f->InitClient(grpc_core::ChannelArgs::FromC(client_args));
  return f;
}

// Tests perAttemptRecvTimeout:
// - 1 retry allowed for ABORTED status
// - both attempts do not receive a response until after perAttemptRecvTimeout
static void test_retry_per_attempt_recv_timeout_on_last_attempt(
    const CoreTestConfiguration& config) {
  grpc_call* c;
  grpc_call* s;
  grpc_call* s0;
  grpc_op ops[6];
  grpc_op* op;
  grpc_metadata_array initial_metadata_recv;
  grpc_metadata_array trailing_metadata_recv;
  grpc_metadata_array request_metadata_recv;
  grpc_call_details call_details;
  grpc_slice request_payload_slice = grpc_slice_from_static_string("foo");
  grpc_slice response_payload_slice = grpc_slice_from_static_string("bar");
  grpc_byte_buffer* request_payload =
      grpc_raw_byte_buffer_create(&request_payload_slice, 1);
  grpc_byte_buffer* response_payload =
      grpc_raw_byte_buffer_create(&response_payload_slice, 1);
  grpc_byte_buffer* request_payload_recv = nullptr;
  grpc_byte_buffer* response_payload_recv = nullptr;
  grpc_status_code status;
  grpc_call_error error;
  grpc_slice details;

  std::string service_config = absl::StrFormat(
      "{\n"
      "  \"methodConfig\": [ {\n"
      "    \"name\": [\n"
      "      { \"service\": \"service\", \"method\": \"method\" }\n"
      "    ],\n"
      "    \"retryPolicy\": {\n"
      "      \"maxAttempts\": 2,\n"
      "      \"initialBackoff\": \"1s\",\n"
      "      \"maxBackoff\": \"120s\",\n"
      "      \"backoffMultiplier\": 1.6,\n"
      "      \"perAttemptRecvTimeout\": \"%ds\",\n"
      "      \"retryableStatusCodes\": [ \"ABORTED\" ]\n"
      "    }\n"
      "  } ]\n"
      "}",
      2 * grpc_test_slowdown_factor());

  grpc_arg args[] = {
      grpc_channel_arg_integer_create(
          const_cast<char*>(GRPC_ARG_EXPERIMENTAL_ENABLE_HEDGING), 1),
      grpc_channel_arg_string_create(const_cast<char*>(GRPC_ARG_SERVICE_CONFIG),
                                     const_cast<char*>(service_config.c_str())),
  };
  grpc_channel_args client_args = {GPR_ARRAY_SIZE(args), args};
  auto f =
      begin_test(config, "test_retry_per_attempt_recv_timeout_on_last_attempt",
                 &client_args, nullptr);

  grpc_core::CqVerifier cqv(f->cq());

  gpr_timespec deadline = grpc_timeout_seconds_to_deadline(10);
  c = grpc_channel_create_call(f->client(), nullptr, GRPC_PROPAGATE_DEFAULTS,
                               f->cq(),
                               grpc_slice_from_static_string("/service/method"),
                               nullptr, deadline, nullptr);
  GPR_ASSERT(c);

  grpc_metadata_array_init(&initial_metadata_recv);
  grpc_metadata_array_init(&trailing_metadata_recv);
  grpc_metadata_array_init(&request_metadata_recv);
  grpc_call_details_init(&call_details);

  memset(ops, 0, sizeof(ops));
  op = ops;
  op->op = GRPC_OP_SEND_INITIAL_METADATA;
  op->data.send_initial_metadata.count = 0;
  op++;
  op->op = GRPC_OP_SEND_MESSAGE;
  op->data.send_message.send_message = request_payload;
  op++;
  op->op = GRPC_OP_RECV_MESSAGE;
  op->data.recv_message.recv_message = &response_payload_recv;
  op++;
  op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
  op++;
  op->op = GRPC_OP_RECV_INITIAL_METADATA;
  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
  op++;
  op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
  op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
  op->data.recv_status_on_client.status = &status;
  op->data.recv_status_on_client.status_details = &details;
  op++;
  error = grpc_call_start_batch(c, ops, static_cast<size_t>(op - ops),
                                grpc_core::CqVerifier::tag(1), nullptr);
  GPR_ASSERT(GRPC_CALL_OK == error);

  // Server gets a call but does not respond to the call.
  error = grpc_server_request_call(f->server(), &s0, &call_details,
                                   &request_metadata_recv, f->cq(), f->cq(),
                                   grpc_core::CqVerifier::tag(101));
  GPR_ASSERT(GRPC_CALL_OK == error);
  cqv.Expect(grpc_core::CqVerifier::tag(101), true);
  cqv.Verify();

  // Make sure the "grpc-previous-rpc-attempts" header was not sent in the
  // initial attempt.
  for (size_t i = 0; i < request_metadata_recv.count; ++i) {
    GPR_ASSERT(!grpc_slice_eq(
        request_metadata_recv.metadata[i].key,
        grpc_slice_from_static_string("grpc-previous-rpc-attempts")));
  }

  grpc_metadata_array_destroy(&request_metadata_recv);
  grpc_metadata_array_init(&request_metadata_recv);
  grpc_call_details_destroy(&call_details);
  grpc_call_details_init(&call_details);

  // Server gets a second call, which it also does not respond to.
  error = grpc_server_request_call(f->server(), &s, &call_details,
                                   &request_metadata_recv, f->cq(), f->cq(),
                                   grpc_core::CqVerifier::tag(201));
  GPR_ASSERT(GRPC_CALL_OK == error);
  cqv.Expect(grpc_core::CqVerifier::tag(201), true);
  cqv.Verify();

  // Now we can unref the first call.
  grpc_call_unref(s0);

  // Make sure the "grpc-previous-rpc-attempts" header was sent in the retry.
  bool found_retry_header = false;
  for (size_t i = 0; i < request_metadata_recv.count; ++i) {
    if (grpc_slice_eq(
            request_metadata_recv.metadata[i].key,
            grpc_slice_from_static_string("grpc-previous-rpc-attempts"))) {
      GPR_ASSERT(grpc_slice_eq(request_metadata_recv.metadata[i].value,
                               grpc_slice_from_static_string("1")));
      found_retry_header = true;
      break;
    }
  }
  GPR_ASSERT(found_retry_header);

  // Client sees call completion.
  cqv.Expect(grpc_core::CqVerifier::tag(1), true);
  cqv.Verify();

  GPR_ASSERT(status == GRPC_STATUS_CANCELLED);
  GPR_ASSERT(
      0 == grpc_slice_str_cmp(details, "retry perAttemptRecvTimeout exceeded"));
  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/service/method"));

  grpc_slice_unref(details);
  grpc_metadata_array_destroy(&initial_metadata_recv);
  grpc_metadata_array_destroy(&trailing_metadata_recv);
  grpc_metadata_array_destroy(&request_metadata_recv);
  grpc_call_details_destroy(&call_details);
  grpc_byte_buffer_destroy(request_payload);
  grpc_byte_buffer_destroy(response_payload);
  grpc_byte_buffer_destroy(request_payload_recv);
  grpc_byte_buffer_destroy(response_payload_recv);

  grpc_call_unref(c);
  grpc_call_unref(s);
}

void retry_per_attempt_recv_timeout_on_last_attempt(
    const CoreTestConfiguration& config) {
  GPR_ASSERT(config.feature_mask & FEATURE_MASK_SUPPORTS_CLIENT_CHANNEL);
  test_retry_per_attempt_recv_timeout_on_last_attempt(config);
}

void retry_per_attempt_recv_timeout_on_last_attempt_pre_init(void) {}
