// Copyright 2017 The Chromium 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 "remoting/base/weighted_samples.h"

#include "base/stl_util.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace remoting {

TEST(WeightedSamplesTest, CalculateWeightedAverage) {
  static constexpr double kWeightFactor = 0.9;
  static constexpr double kExpected[] = {
    1,
    1.5263157894736843,
    2.0701107011070110,
    2.6312881651642916,
  };
  WeightedSamples samples(kWeightFactor);
  for (size_t i = 0; i < base::size(kExpected); i++) {
    samples.Record(i + 1);
    EXPECT_DOUBLE_EQ(kExpected[i], samples.WeightedAverage());
  }
}

TEST(WeightedSamplesTest, CalculateWeightedAverage_SameValues) {
  WeightedSamples samples(0.9);
  for (int i = 0; i < 100; i++) {
    samples.Record(100);
  }
  EXPECT_EQ(samples.WeightedAverage(), 100);
}

TEST(WeightedSamplesTest, ReturnZeroIfNoRecords) {
  WeightedSamples samples(0.9);
  EXPECT_EQ(samples.WeightedAverage(), 0);
}

}  // namespace remoting