/*
 *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "system_wrappers/include/metrics.h"

#include <map>
#include <string>

#include "absl/strings/string_view.h"
#include "rtc_base/checks.h"
#include "test/gmock.h"
#include "test/gtest.h"

using ::testing::ElementsAre;
using ::testing::IsEmpty;
using ::testing::Pair;

#if RTC_METRICS_ENABLED
namespace webrtc {
namespace {
constexpr int kSample = 22;

void AddSparseSample(absl::string_view name, int sample) {
  RTC_HISTOGRAM_COUNTS_SPARSE_100(name, sample);
}
void AddSampleWithVaryingName(int index, absl::string_view name, int sample) {
  RTC_HISTOGRAMS_COUNTS_100(index, name, sample);
}
}  // namespace

class MetricsTest : public ::testing::Test {
 public:
  MetricsTest() {}

 protected:
  void SetUp() override { metrics::Reset(); }
};

TEST_F(MetricsTest, InitiallyNoSamples) {
  EXPECT_EQ(0, metrics::NumSamples("NonExisting"));
  EXPECT_EQ(0, metrics::NumEvents("NonExisting", kSample));
  EXPECT_THAT(metrics::Samples("NonExisting"), IsEmpty());
}

TEST_F(MetricsTest, RtcHistogramPercent_AddSample) {
  const std::string kName = "Percentage";
  RTC_HISTOGRAM_PERCENTAGE(kName, kSample);
  EXPECT_EQ(1, metrics::NumSamples(kName));
  EXPECT_EQ(1, metrics::NumEvents(kName, kSample));
  EXPECT_THAT(metrics::Samples(kName), ElementsAre(Pair(kSample, 1)));
}

TEST_F(MetricsTest, RtcHistogramEnumeration_AddSample) {
  const std::string kName = "Enumeration";
  RTC_HISTOGRAM_ENUMERATION(kName, kSample, kSample + 1);
  EXPECT_EQ(1, metrics::NumSamples(kName));
  EXPECT_EQ(1, metrics::NumEvents(kName, kSample));
  EXPECT_THAT(metrics::Samples(kName), ElementsAre(Pair(kSample, 1)));
}

TEST_F(MetricsTest, RtcHistogramBoolean_AddSample) {
  const std::string kName = "Boolean";
  const int kSampleZero = 0;
  RTC_HISTOGRAM_BOOLEAN(kName, kSampleZero);
  EXPECT_EQ(1, metrics::NumSamples(kName));
  EXPECT_EQ(1, metrics::NumEvents(kName, kSampleZero));
  EXPECT_THAT(metrics::Samples(kName), ElementsAre(Pair(kSampleZero, 1)));
}

TEST_F(MetricsTest, RtcHistogramCountsSparse_AddSample) {
  const std::string kName = "CountsSparse100";
  RTC_HISTOGRAM_COUNTS_SPARSE_100(kName, kSample);
  EXPECT_EQ(1, metrics::NumSamples(kName));
  EXPECT_EQ(1, metrics::NumEvents(kName, kSample));
  EXPECT_THAT(metrics::Samples(kName), ElementsAre(Pair(kSample, 1)));
}

TEST_F(MetricsTest, RtcHistogramCounts_AddSample) {
  const std::string kName = "Counts100";
  RTC_HISTOGRAM_COUNTS_100(kName, kSample);
  EXPECT_EQ(1, metrics::NumSamples(kName));
  EXPECT_EQ(1, metrics::NumEvents(kName, kSample));
  EXPECT_THAT(metrics::Samples(kName), ElementsAre(Pair(kSample, 1)));
}

TEST_F(MetricsTest, RtcHistogramCounts_AddMultipleSamples) {
  const std::string kName = "Counts200";
  const int kNumSamples = 10;
  std::map<int, int> samples;
  for (int i = 1; i <= kNumSamples; ++i) {
    RTC_HISTOGRAM_COUNTS_200(kName, i);
    EXPECT_EQ(1, metrics::NumEvents(kName, i));
    EXPECT_EQ(i, metrics::NumSamples(kName));
    samples[i] = 1;
  }
  EXPECT_EQ(samples, metrics::Samples(kName));
}

TEST_F(MetricsTest, RtcHistogramsCounts_AddSample) {
  AddSampleWithVaryingName(0, "Name1", kSample);
  AddSampleWithVaryingName(1, "Name2", kSample + 1);
  AddSampleWithVaryingName(2, "Name3", kSample + 2);
  EXPECT_EQ(1, metrics::NumSamples("Name1"));
  EXPECT_EQ(1, metrics::NumSamples("Name2"));
  EXPECT_EQ(1, metrics::NumSamples("Name3"));
  EXPECT_EQ(1, metrics::NumEvents("Name1", kSample + 0));
  EXPECT_EQ(1, metrics::NumEvents("Name2", kSample + 1));
  EXPECT_EQ(1, metrics::NumEvents("Name3", kSample + 2));
  EXPECT_THAT(metrics::Samples("Name1"), ElementsAre(Pair(kSample + 0, 1)));
  EXPECT_THAT(metrics::Samples("Name2"), ElementsAre(Pair(kSample + 1, 1)));
  EXPECT_THAT(metrics::Samples("Name3"), ElementsAre(Pair(kSample + 2, 1)));
}

#if RTC_DCHECK_IS_ON && GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
using MetricsDeathTest = MetricsTest;
TEST_F(MetricsDeathTest, RtcHistogramsCounts_InvalidIndex) {
  EXPECT_DEATH(RTC_HISTOGRAMS_COUNTS_1000(-1, "Name", kSample), "");
  EXPECT_DEATH(RTC_HISTOGRAMS_COUNTS_1000(3, "Name", kSample), "");
  EXPECT_DEATH(RTC_HISTOGRAMS_COUNTS_1000(3u, "Name", kSample), "");
}
#endif

TEST_F(MetricsTest, RtcHistogramSparse_NonConstantNameWorks) {
  AddSparseSample("Sparse1", kSample);
  AddSparseSample("Sparse2", kSample);
  EXPECT_EQ(1, metrics::NumSamples("Sparse1"));
  EXPECT_EQ(1, metrics::NumSamples("Sparse2"));
  EXPECT_THAT(metrics::Samples("Sparse1"), ElementsAre(Pair(kSample, 1)));
  EXPECT_THAT(metrics::Samples("Sparse2"), ElementsAre(Pair(kSample, 1)));
}

}  // namespace webrtc
#endif