// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "src/uploader/shipping_manager.h"

#include <chrono>
#include <memory>
#include <set>
#include <string>
#include <utility>
#include <vector>

#include "src/lib/clearcut/clearcut.pb.h"
#include "src/lib/util/posix_file_system.h"
#include "src/logger/fake_logger.h"
#include "src/logging.h"
#include "src/observation_store/memory_observation_store.h"
#include "src/observation_store/observation_store.h"
#include "src/pb/clearcut_extensions.pb.h"
#include "src/system_data/fake_system_data.h"
#include "third_party/gflags/include/gflags/gflags.h"
#include "third_party/googletest/googletest/include/gtest/gtest.h"
#include "third_party/protobuf/src/google/protobuf/util/delimited_message_util.h"

namespace cobalt::uploader {

using cobalt::clearcut_extensions::LogEventExtension;
using lib::statusor::StatusOr;
using logger::PerProjectBytesUploadedMetricDimensionStatus::Succeeded;
using logger::testing::FakeLogger;
using observation_store::MemoryObservationStore;
using observation_store::ObservationStore;
using util::EncryptedMessageMaker;

namespace {

constexpr uint32_t kCustomerId = 11;
constexpr uint32_t kProjectId = 12;
constexpr uint32_t kMetricId = 13;

constexpr size_t kMaxBytesPerObservation = 50;
constexpr size_t kMaxBytesPerEnvelope = 200;
constexpr size_t kMaxBytesTotal = 1000;
const std::chrono::seconds kMaxSeconds = UploadScheduler::kMaxSeconds;

constexpr int kHttpOk = 200;
constexpr int kHttpInternalServerError = 500;

class FakeHTTPClient : public lib::clearcut::HTTPClient {
 public:
  std::future<StatusOr<lib::clearcut::HTTPResponse>> Post(
      lib::clearcut::HTTPRequest request,
      std::chrono::steady_clock::time_point /*ignored*/) override {
    std::unique_lock<std::mutex> lock(mutex);
    util::MessageDecrypter decrypter("");

    lib::clearcut::LogRequest req;
    req.ParseFromString(request.body);
    EXPECT_GT(req.log_event_size(), 0);
    for (const auto& event : req.log_event()) {
      EXPECT_TRUE(event.HasExtension(LogEventExtension::ext));
      auto log_event = event.GetExtension(LogEventExtension::ext);
      Envelope recovered_envelope;
      EXPECT_TRUE(
          decrypter.DecryptMessage(log_event.cobalt_encrypted_envelope(), &recovered_envelope));
      EXPECT_EQ(1, recovered_envelope.batch_size());
      EXPECT_EQ(kMetricId, recovered_envelope.batch(0).meta_data().metric_id());
      observation_count += recovered_envelope.batch(0).encrypted_observation_size();
    }
    send_call_count++;

    lib::clearcut::HTTPResponse response;
    response.http_code = http_response_code_to_return;
    lib::clearcut::LogResponse resp;
    resp.SerializeToString(&response.response);

    std::promise<StatusOr<lib::clearcut::HTTPResponse>> response_promise;
    response_promise.set_value(std::move(response));

    return response_promise.get_future();
  }

  std::mutex mutex;
  int http_response_code_to_return = kHttpOk;
  int send_call_count = 0;
  int observation_count = 0;
};

std::unique_ptr<EncryptedMessage> CreateObservationMessage(size_t num_bytes) {
  CHECK_GT(num_bytes, 4);
  auto message = std::make_unique<EncryptedMessage>();
  // Because the MemoryObservationStore counts the size of an Observation
  // to be the ciphertext size + 4, we set the ciphertext size to be
  // num_bytes - 4.
  message->set_ciphertext(std::string(num_bytes - 4, 'x'));
  return message;
}

std::unique_ptr<ObservationMetadata> CreateObservationMetadata() {
  auto metadata = std::make_unique<ObservationMetadata>();
  metadata->set_customer_id(kCustomerId);
  metadata->set_project_id(kProjectId);
  metadata->set_metric_id(kMetricId);
  return metadata;
}
}  // namespace

class ShippingManagerTest : public ::testing::Test {
 public:
  ShippingManagerTest()
      : encrypt_to_shuffler_(EncryptedMessageMaker::MakeUnencrypted()),
        encrypt_to_analyzer_(EncryptedMessageMaker::MakeUnencrypted()),
        observation_store_(kMaxBytesPerObservation, kMaxBytesPerEnvelope, kMaxBytesTotal) {}

 protected:
  void Init(std::chrono::seconds schedule_interval, std::chrono::seconds min_interval) {
    UploadScheduler upload_scheduler(schedule_interval, min_interval);
    auto http_client = std::make_unique<FakeHTTPClient>();
    http_client_ = http_client.get();
    shipping_manager_ = std::make_unique<ClearcutV1ShippingManager>(
        upload_scheduler, &observation_store_, encrypt_to_shuffler_.get(),
        encrypt_to_analyzer_.get(),
        std::make_unique<lib::clearcut::ClearcutUploader>("https://test.com",
                                                          std::move(http_client)),
        /*log_source_id=*/11, /*internal_logger=*/nullptr, /*max_attempts_per_upload=*/1);
    shipping_manager_->Start();
  }

  ObservationStore::StoreStatus AddObservation(size_t num_bytes) {
    auto retval = observation_store_.StoreObservation(CreateObservationMessage(num_bytes),
                                                      CreateObservationMetadata());
    shipping_manager_->NotifyObservationsAdded();
    return retval;
  }

  void CheckCallCount(int expected_call_count, int expected_observation_count) {
    ASSERT_NE(nullptr, http_client_);
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    EXPECT_EQ(expected_call_count, http_client_->send_call_count);
    EXPECT_EQ(expected_observation_count, http_client_->observation_count);
  }

 private:
  std::unique_ptr<EncryptedMessageMaker> encrypt_to_shuffler_;
  std::unique_ptr<EncryptedMessageMaker> encrypt_to_analyzer_;
  MemoryObservationStore observation_store_;
  system_data::FakeSystemData system_data_;

 protected:
  std::unique_ptr<ClearcutV1ShippingManager> shipping_manager_;
  FakeHTTPClient* http_client_ = nullptr;
};

// We construct a ShippingManager and destruct it without calling any methods.
// This tests that the destructor requests that the worker thread terminate
// and then waits for it to terminate.
TEST_F(ShippingManagerTest, ConstructAndDestruct) { Init(kMaxSeconds, kMaxSeconds); }

// We construct a ShippingManager and add one small Observation to it.
// Before the ShippingManager has a chance to send the Observation we
// destruct it. We test that the Add() returns OK and the destructor
// succeeds.
TEST_F(ShippingManagerTest, AddOneObservationAndDestruct) {
  Init(kMaxSeconds, kMaxSeconds);
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
}

// We add one Observation, confirm that it is not immediately sent,
// invoke RequestSendSoon, wait for the Observation to be sent, confirm
// that it was sent.
TEST_F(ShippingManagerTest, SendOne) {
  // Init with a very long time for the regular schedule interval but
  // zero for the minimum interval so the test doesn't have to wait.
  Init(kMaxSeconds, std::chrono::seconds::zero());
  // Add one Observation().
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));

  // Confirm it has not been sent yet.
  CheckCallCount(0, 0);

  // Invoke RequestSendSoon.
  shipping_manager_->RequestSendSoon();

  // Wait for it to be sent.
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Confirm it has been sent.
  EXPECT_EQ(1u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(0u, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
  CheckCallCount(1, 1);
}

// Performs the same thest as SendOne but makes sure the right values were logged to the internal
// metrics object.
TEST_F(ShippingManagerTest, SendOneLoggedMetrics) {
  // Init with a very long time for the regular schedule interval but
  // zero for the minimum interval so the test doesn't have to wait.
  Init(kMaxSeconds, std::chrono::seconds::zero());

  FakeLogger logger;
  shipping_manager_->ResetInternalMetrics(&logger);

  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  shipping_manager_->RequestSendSoon();
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Same checks as the pervious test.
  EXPECT_EQ(1u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(0u, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
  CheckCallCount(1, 1);

  // Attempt and Succeed in the Shipping Manager for a project and Attempt and
  // Succeed in Clearcut Uploader.
  EXPECT_EQ(4, logger.call_count());

  auto event = logger.last_event_logged();  // The last Succeed for an Observation Batch.
  EXPECT_TRUE(event.has_count_event());
  EXPECT_EQ(1, event.count_event().event_code_size());
  EXPECT_EQ(Succeeded, event.count_event().event_code(0));
  EXPECT_EQ(absl::StrCat(kCustomerId, "/", kProjectId), event.count_event().component());
  EXPECT_LE(40, event.count_event().count());  // This is an estimate.
}

// We add two Observations, confirm that they are not immediately sent,
// invoke RequestSendSoon, wait for the Observations to be sent, confirm
// that they were sent together in a single Envelope.
TEST_F(ShippingManagerTest, SendTwo) {
  // Init with a very long time for the regular schedule interval but
  // zero for the minimum interval so the test doesn't have to wait.
  Init(kMaxSeconds, std::chrono::seconds::zero());

  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));

  CheckCallCount(0, 0);

  // Request send soon.
  shipping_manager_->RequestSendSoon();

  // Wait for both Observations to be sent.
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Confirm the two Observations were sent together in a single Envelope.
  EXPECT_EQ(1u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(0u, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
  CheckCallCount(1, 2);
}

// Performs the same thest as SendTwo but makes sure the right values were logged to the internal
// metrics object.
TEST_F(ShippingManagerTest, SendTwoLoggedMetrics) {
  Init(kMaxSeconds, std::chrono::seconds::zero());

  FakeLogger logger;
  shipping_manager_->ResetInternalMetrics(&logger);

  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));

  CheckCallCount(0, 0);
  shipping_manager_->RequestSendSoon();
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Same checks as the pervious test.
  EXPECT_EQ(1u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(0u, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
  CheckCallCount(1, 2);

  // Attempt and Succeed in the Shipping Manager and Attempt and Succeed in Clearcut Uploader for
  // the envelope.
  EXPECT_EQ(4, logger.call_count());

  auto event = logger.last_event_logged();  // The last Succeed for an Observation Batch.
  EXPECT_TRUE(event.has_count_event());
  EXPECT_EQ(1, event.count_event().event_code_size());
  EXPECT_EQ(Succeeded, event.count_event().event_code(0));
  EXPECT_EQ(absl::StrCat(kCustomerId, "/", kProjectId), event.count_event().component());
  EXPECT_LE(2 * 40, event.count_event().count());  // This is an estimate.
}

// Trys to add an Observation that is too big. Tests that kObservationTooBig
// is returned.
TEST_F(ShippingManagerTest, ObservationTooBig) {
  // Init with a very long time for the regular schedule interval but
  // zero for the minimum interval so the test doesn't have to wait.
  Init(kMaxSeconds, std::chrono::seconds::zero());

  // Add one observation that is too big.
  EXPECT_EQ(ObservationStore::kObservationTooBig, AddObservation(60));
}

// Add multiple Observations and allow them to be sent on the regular
// schedule.
TEST_F(ShippingManagerTest, ScheduledSend) {
  // We set both schedule_interval_ and min_interval_ to zero so the test
  // does not have to wait.
  Init(std::chrono::seconds::zero(), std::chrono::seconds::zero());

  // Add two Observations but do not invoke RequestSendSoon() and do
  // not add enough Observations to exceed envelope_send_threshold_size_.
  for (int i = 0; i < 2; i++) {
    EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  }
  // Wait for the scheduled send
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // We do not check the number of sends because that depends on the
  // timing interaction of the test thread and the worker thread and so it
  // would be flaky. Just check that all 3 Observations were sent.
  std::unique_lock<std::mutex> lock(http_client_->mutex);
  EXPECT_EQ(2, http_client_->observation_count);
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
}

// Tests the ShippingManager in the case that the ObservationStore returns
// kStoreFull.
//
// kMaxBytesTotal = 1000 and we are using Observations of size 40 bytes.
// 40 * 25 = 1000. The MemoryObservationStore will allow the 26th Observation
// to be added and then reject the 27th Observation.
TEST_F(ShippingManagerTest, ExceedMaxBytesTotal) {
  // Init with a very long time for the regular schedule interval but
  // zero for the minimum interval so the test doesn't have to wait.
  Init(kMaxSeconds, std::chrono::seconds::zero());
  // Configure the HttpClient to fail every time.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpInternalServerError;
  }

  // We can add 15 observations without the ObservationStore reporting that
  // it is almost full.
  for (int i = 0; i < 15; i++) {  // NOLINT readability-magic-numbers
    EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
    shipping_manager_->WaitUntilWorkerWaiting(kMaxSeconds);
  }

  // The ObservationStore was never almost full so the ShippingManager
  // should not have attempted to do a send.
  EXPECT_EQ(0u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(0u, shipping_manager_->num_failed_attempts());

  // The sixteenth Observation causes the ObservationStore to become almost
  // full and that causes the ShippingManager to attempt a send.
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));

  shipping_manager_->WaitUntilWorkerWaiting(kMaxSeconds);

  auto num_send_attempts = shipping_manager_->num_send_attempts();
  EXPECT_GT(num_send_attempts, 0u);
  EXPECT_EQ(num_send_attempts, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::UNKNOWN, shipping_manager_->last_send_status().error_code());

  // We can add 10 more Observations bringing the total to 26,
  // without the ObservationStore being full.
  for (int i = 0; i < 10; i++) {
    EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  }
  shipping_manager_->WaitUntilWorkerWaiting(kMaxSeconds);

  // Because the ObservationStore is almost full the ShippingManager has
  // been attempting additional sends.
  EXPECT_GT(shipping_manager_->num_send_attempts(), num_send_attempts);
  num_send_attempts = shipping_manager_->num_send_attempts();
  EXPECT_EQ(num_send_attempts, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::UNKNOWN, shipping_manager_->last_send_status().error_code());

  // The 27th Observation will be rejected with kStoreFull.
  EXPECT_EQ(ObservationStore::kStoreFull, AddObservation(40));

  // Now configure the HttpClient to start succeeding,
  // and reset the counts.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpOk;
    http_client_->send_call_count = 0;
    http_client_->observation_count = 0;
  }

  // Send all 26 of the accumulated Observations.
  shipping_manager_->RequestSendSoon();
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // All 26 successfully-added Observations should have been sent in six
  // envelopes
  CheckCallCount(6, 26);  // NOLINT readability-magic-numbers
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
  EXPECT_GT(shipping_manager_->num_send_attempts(), num_send_attempts);
  num_send_attempts = shipping_manager_->num_send_attempts();
  EXPECT_GT(num_send_attempts, shipping_manager_->num_failed_attempts());
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());

  // Now we can add a 27th Observation and send it.
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  shipping_manager_->RequestSendSoon();
  shipping_manager_->WaitUntilIdle(kMaxSeconds);
  CheckCallCount(7, 27);  // NOLINT readability-magic-numbers
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
}

// Tests that when the total amount of accumulated Observation data exceeds
// total_bytes_send_threshold_  then RequestSendSoon() will be invoked.
TEST_F(ShippingManagerTest, TotalBytesSendThreshold) {
  // Init with a very long time for the regular schedule interval but
  // zero for the minimum interval so the test doesn't have to wait.
  Init(kMaxSeconds, std::chrono::seconds::zero());

  // Configure the HttpClient to fail every time so that we can
  // accumulate Observation data in memory.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpInternalServerError;
  }

  // total_bytes_send_threshold_ = 0.6 * max_bytes_total_.
  // kMaxBytesTotal = 1000 so total_bytes_send_threshold_ = 600.
  // We are using Observations of size 40 and 40 * 15 = 600 so the first
  // Observation that causes us to exceed total_bytes_send_threshold_ is #16.
  //
  // Add 15 Observations. We want to do this in such a way that we don't
  // exceed max_bytes_per_envelope_.  Each time we will invoke
  // RequestSendSoon() and then WaitUntilWorkerWaiting() so that we know that
  // between invocations of AddObservtion() the worker thread will complete
  // one execution of SendAllEnvelopes().
  for (int i = 0; i < 15; i++) {  // NOLINT readability-magic-numbers
    EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
    if (i < 15) {  // NOLINT readability-magic-numbers
      // After having added 15 observations we have exceeded the
      // ObservationStore's almost_full_threshold_ and this means that each
      // invocation of AddEncryptedObservation() followed by a
      // NotifyObservationsAdded() automatically invokes RequestSendSoon() and
      // so we don't want to invoke it again here.
      shipping_manager_->RequestSendSoon();
    }
    shipping_manager_->WaitUntilWorkerWaiting(kMaxSeconds);
  }

  // We expect there to have been 45 calls to SendRetryer::SendToShuffler() in
  // which the Envelopes sent contained a total of 195 Observations. Here we
  // explain how this was calculated. See the comments at the top of the file on
  // kMinEnvelopeSendSize. There it is explained that the ObservationStore will
  // attempt to bundle together up to 5 observations into a sinle envelope
  // before sending. None of the sends succeed so the ObservationStore keeps
  // accumulating more Envelopes containing 5 Observations that failed to send.
  // Below is the complete pattern of send attempts. Each set in braces
  // represents one execution of SendAllEnvelopes(). The numbers in each set
  // represent the invocations of SendEnvelopeToBackend() with an Envelope that
  // contains that many observations.
  //
  // {1, 1, 1}, {2, 2, 2}, {3, 3, 3}, {4, 4, 4}, {5, 5, 5}, {5, 5, 5}, ...
  //
  // Thus the total number of send attempts is the total number of numbers:
  // 3 * 15 = 45
  //
  // And the total number of Observations is the sum of all the numbers:
  // (1 + 2 + 3 + 4 + 5) * 3 + (5*3*(15-5)) = 195
  CheckCallCount(45, 195);  // NOLINT readability-magic-numbers

  // Now configure the HttpClient to start succeeding,
  // and reset the counts.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpOk;
    http_client_->send_call_count = 0;
    http_client_->observation_count = 0;
  }

  // Now we send the 16th Observattion. But notice that we do *not* invoke
  // RequestSendSoon() this time. So the reason the Observations get sent
  // now is because we are exceeding total_bytes_send_threshold_.
  EXPECT_EQ(ObservationStore::kOk, AddObservation(40));

  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // All 16 Observations should have been sent in 4 envelopes as {5, 5, 5, 1}.
  CheckCallCount(4, 16);  // NOLINT readability-magic-numbers
}

// Test the version of the method RequestSendSoon() that takes a callback.
// We test that the callback is invoked with success = true when the send
// succeeds and with success = false when the send fails.
TEST_F(ShippingManagerTest, RequestSendSoonWithCallback) {
  Init(kMaxSeconds, std::chrono::seconds::zero());

  // Invoke RequestSendSoon() with a callback before any Observations are
  // added.
  bool captured_success_arg = false;
  shipping_manager_->RequestSendSoon(
      [&captured_success_arg](bool success) { captured_success_arg = success; });
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Check that the callback was invoked synchronously with success = true.
  CheckCallCount(0, 0);
  EXPECT_EQ(0u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(0u, shipping_manager_->num_failed_attempts());
  EXPECT_TRUE(captured_success_arg);

  // Arrange for the first send to fail.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpInternalServerError;
  }

  // Add an Observation, invoke RequestSendSoon() with a callback.
  shipping_manager_->WaitUntilIdle(kMaxSeconds);
  EXPECT_EQ(ObservationStore::kOk, AddObservation(31));
  shipping_manager_->RequestSendSoon(
      [&captured_success_arg](bool success) { captured_success_arg = success; });
  shipping_manager_->WaitUntilWorkerWaiting(kMaxSeconds);

  // Check that the callback was invoked with success = false.
  CheckCallCount(3, 3);
  EXPECT_EQ(3u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(3u, shipping_manager_->num_failed_attempts());
  EXPECT_FALSE(captured_success_arg);

  // Arrange for the next send to succeed.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpOk;
  }

  // Don't add another Observation but invoke RequestSendSoon() with a
  // callback.
  shipping_manager_->RequestSendSoon(
      [&captured_success_arg](bool success) { captured_success_arg = success; });
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Check that the callback was invoked with success = true.
  CheckCallCount(4, 4);
  EXPECT_EQ(4u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(3u, shipping_manager_->num_failed_attempts());
  EXPECT_TRUE(captured_success_arg);

  // Arrange for the next send to fail.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpInternalServerError;
  }

  // Invoke RequestSendSoon without a callback just so that there is an
  // Observation cached in the inner EnvelopeMaker.
  EXPECT_EQ(ObservationStore::kOk, AddObservation(31));
  shipping_manager_->RequestSendSoon();
  shipping_manager_->WaitUntilWorkerWaiting(kMaxSeconds);
  CheckCallCount(7, 7);  // NOLINT readability-magic-numbers
  EXPECT_EQ(7u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(6u, shipping_manager_->num_failed_attempts());

  // Arrange for the next send to succeed.
  {
    std::unique_lock<std::mutex> lock(http_client_->mutex);
    http_client_->http_response_code_to_return = kHttpOk;
  }

  // Add an Observation, invoke RequestSendSoon() with a callback.
  EXPECT_EQ(ObservationStore::kOk, AddObservation(31));
  shipping_manager_->RequestSendSoon(
      [&captured_success_arg](bool success) { captured_success_arg = success; });
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  // Check that the callback was invoked with success = true.
  CheckCallCount(8, 9);  // NOLINT readability-magic-numbers
  EXPECT_EQ(8u, shipping_manager_->num_send_attempts());
  EXPECT_EQ(6u, shipping_manager_->num_failed_attempts());
  EXPECT_TRUE(captured_success_arg);
}

constexpr char test_file_base[] = "/tmp/local_shipping_manager_test";

std::string GetTestFileName(const std::string& base) {
  std::stringstream fname;
  fname << base << "_"
        << std::chrono::duration_cast<std::chrono::milliseconds>(
               std::chrono::system_clock::now().time_since_epoch())
               .count();
  return fname.str();
}

class LocalShippingManagerTest : public ::testing::Test {
 public:
  LocalShippingManagerTest()
      : observation_store_(kMaxBytesPerObservation, kMaxBytesPerEnvelope, kMaxBytesTotal),
        test_file_name_(GetTestFileName(test_file_base)) {}

 protected:
  void SetUp() override {
    fs_.Delete(test_file_name_);
    shipping_manager_ = std::make_unique<LocalShippingManager>(
        &observation_store_, test_file_name_, std::make_unique<util::PosixFileSystem>());
    shipping_manager_->Start();
  }

  ObservationStore::StoreStatus AddObservation(size_t num_bytes) {
    auto retval = observation_store_.StoreObservation(CreateObservationMessage(num_bytes),
                                                      CreateObservationMetadata());
    shipping_manager_->NotifyObservationsAdded();
    return retval;
  }

  void CheckObservationCount(int expected_observation_count) {
    auto ifs = fs_.NewProtoInputStream(test_file_name_);
    ASSERT_EQ(util::StatusCode::OK, ifs.status().error_code());
    int observation_count = 0;
    Envelope envelope;
    bool clean_eof = false;
    while (google::protobuf::util::ParseDelimitedFromZeroCopyStream(
        &envelope, ifs.ValueOrDie().get(), &clean_eof)) {
      for (const auto& batch : envelope.batch()) {
        observation_count += batch.encrypted_observation_size();
      }
      envelope.Clear();
    }
    EXPECT_EQ(true, clean_eof);
    EXPECT_EQ(expected_observation_count, observation_count);
  }

 private:
  MemoryObservationStore observation_store_;

 protected:
  std::string test_file_name_;
  std::unique_ptr<ShippingManager> shipping_manager_;
  util::PosixFileSystem fs_;
};

// Add multiple Observations and allow them to be saved.
TEST_F(LocalShippingManagerTest, ScheduledSave) {
  // Add two Observations but do not invoke RequestSendSoon() and do
  // not add enough Observations to exceed envelope_send_threshold_size_.
  for (int i = 0; i < 2; i++) {
    EXPECT_EQ(ObservationStore::kOk, AddObservation(40));
  }
  // Wait for the save to disk.
  shipping_manager_->WaitUntilIdle(kMaxSeconds);

  CheckObservationCount(2);
  EXPECT_EQ(grpc::OK, shipping_manager_->last_send_status().error_code());
}

}  // namespace cobalt::uploader