/*
 *  Copyright (c) 2018 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 "modules/audio_processing/aec3/api_call_jitter_metrics.h"

#include "modules/audio_processing/aec3/aec3_common.h"
#include "test/gtest.h"

namespace webrtc {

// Verify constant jitter.
TEST(ApiCallJitterMetrics, ConstantJitter) {
  for (int jitter = 1; jitter < 20; ++jitter) {
    ApiCallJitterMetrics metrics;
    for (size_t k = 0; k < 30 * kNumBlocksPerSecond; ++k) {
      for (int j = 0; j < jitter; ++j) {
        metrics.ReportRenderCall();
      }

      for (int j = 0; j < jitter; ++j) {
        metrics.ReportCaptureCall();

        if (metrics.WillReportMetricsAtNextCapture()) {
          EXPECT_EQ(jitter, metrics.render_jitter().min());
          EXPECT_EQ(jitter, metrics.render_jitter().max());
          EXPECT_EQ(jitter, metrics.capture_jitter().min());
          EXPECT_EQ(jitter, metrics.capture_jitter().max());
        }
      }
    }
  }
}

// Verify peaky jitter for the render.
TEST(ApiCallJitterMetrics, JitterPeakRender) {
  constexpr int kMinJitter = 2;
  constexpr int kJitterPeak = 10;
  constexpr int kPeakInterval = 100;

  ApiCallJitterMetrics metrics;
  int render_surplus = 0;

  for (size_t k = 0; k < 30 * kNumBlocksPerSecond; ++k) {
    const int num_render_calls =
        k % kPeakInterval == 0 ? kJitterPeak : kMinJitter;
    for (int j = 0; j < num_render_calls; ++j) {
      metrics.ReportRenderCall();
      ++render_surplus;
    }

    ASSERT_LE(kMinJitter, render_surplus);
    const int num_capture_calls =
        render_surplus == kMinJitter ? kMinJitter : kMinJitter + 1;
    for (int j = 0; j < num_capture_calls; ++j) {
      metrics.ReportCaptureCall();

      if (metrics.WillReportMetricsAtNextCapture()) {
        EXPECT_EQ(kMinJitter, metrics.render_jitter().min());
        EXPECT_EQ(kJitterPeak, metrics.render_jitter().max());
        EXPECT_EQ(kMinJitter, metrics.capture_jitter().min());
        EXPECT_EQ(kMinJitter + 1, metrics.capture_jitter().max());
      }
      --render_surplus;
    }
  }
}

// Verify peaky jitter for the capture.
TEST(ApiCallJitterMetrics, JitterPeakCapture) {
  constexpr int kMinJitter = 2;
  constexpr int kJitterPeak = 10;
  constexpr int kPeakInterval = 100;

  ApiCallJitterMetrics metrics;
  int capture_surplus = kMinJitter;

  for (size_t k = 0; k < 30 * kNumBlocksPerSecond; ++k) {
    ASSERT_LE(kMinJitter, capture_surplus);
    const int num_render_calls =
        capture_surplus == kMinJitter ? kMinJitter : kMinJitter + 1;
    for (int j = 0; j < num_render_calls; ++j) {
      metrics.ReportRenderCall();
      --capture_surplus;
    }

    const int num_capture_calls =
        k % kPeakInterval == 0 ? kJitterPeak : kMinJitter;
    for (int j = 0; j < num_capture_calls; ++j) {
      metrics.ReportCaptureCall();

      if (metrics.WillReportMetricsAtNextCapture()) {
        EXPECT_EQ(kMinJitter, metrics.render_jitter().min());
        EXPECT_EQ(kMinJitter + 1, metrics.render_jitter().max());
        EXPECT_EQ(kMinJitter, metrics.capture_jitter().min());
        EXPECT_EQ(kJitterPeak, metrics.capture_jitter().max());
      }
      ++capture_surplus;
    }
  }
}

}  // namespace webrtc