/*
 *  Copyright (c) 2017 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/render_delay_controller.h"

#include <algorithm>
#include <memory>
#include <string>
#include <vector>

#include "modules/audio_processing/aec3/aec3_common.h"
#include "modules/audio_processing/aec3/block_processor.h"
#include "modules/audio_processing/aec3/decimator.h"
#include "modules/audio_processing/aec3/render_delay_buffer.h"
#include "modules/audio_processing/logging/apm_data_dumper.h"
#include "modules/audio_processing/test/echo_canceller_test_tools.h"
#include "rtc_base/random.h"
#include "rtc_base/strings/string_builder.h"
#include "test/gtest.h"

namespace webrtc {
namespace {

std::string ProduceDebugText(int sample_rate_hz) {
  rtc::StringBuilder ss;
  ss << "Sample rate: " << sample_rate_hz;
  return ss.Release();
}

std::string ProduceDebugText(int sample_rate_hz, size_t delay) {
  rtc::StringBuilder ss;
  ss << ProduceDebugText(sample_rate_hz) << ", Delay: " << delay;
  return ss.Release();
}

constexpr size_t kDownSamplingFactors[] = {2, 4, 8};

}  // namespace

// Verifies the output of GetDelay when there are no AnalyzeRender calls.
TEST(RenderDelayController, NoRenderSignal) {
  for (size_t num_render_channels : {1, 2, 8}) {
    std::vector<std::vector<float>> block(1,
                                          std::vector<float>(kBlockSize, 0.f));
    EchoCanceller3Config config;
    for (size_t num_matched_filters = 4; num_matched_filters == 10;
         num_matched_filters++) {
      for (auto down_sampling_factor : kDownSamplingFactors) {
        config.delay.down_sampling_factor = down_sampling_factor;
        config.delay.num_filters = num_matched_filters;
        for (auto rate : {16000, 32000, 48000}) {
          SCOPED_TRACE(ProduceDebugText(rate));
          std::unique_ptr<RenderDelayBuffer> delay_buffer(
              RenderDelayBuffer::Create(config, rate, num_render_channels));
          std::unique_ptr<RenderDelayController> delay_controller(
              RenderDelayController::Create(config, rate));
          for (size_t k = 0; k < 100; ++k) {
            auto delay = delay_controller->GetDelay(
                delay_buffer->GetDownsampledRenderBuffer(),
                delay_buffer->Delay(), block);
            EXPECT_FALSE(delay->delay);
          }
        }
      }
    }
  }
}

// Verifies the basic API call sequence.
TEST(RenderDelayController, BasicApiCalls) {
  for (size_t num_capture_channels : {1, 2, 4}) {
    for (size_t num_render_channels : {1, 2, 8}) {
      std::vector<std::vector<float>> capture_block(
          num_capture_channels, std::vector<float>(kBlockSize, 0.f));
      absl::optional<DelayEstimate> delay_blocks;
      for (size_t num_matched_filters = 4; num_matched_filters == 10;
           num_matched_filters++) {
        for (auto down_sampling_factor : kDownSamplingFactors) {
          EchoCanceller3Config config;
          config.delay.down_sampling_factor = down_sampling_factor;
          config.delay.num_filters = num_matched_filters;
          for (auto rate : {16000, 32000, 48000}) {
            std::vector<std::vector<std::vector<float>>> render_block(
                NumBandsForRate(rate),
                std::vector<std::vector<float>>(
                    num_render_channels, std::vector<float>(kBlockSize, 0.f)));
            std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
                RenderDelayBuffer::Create(config, rate, num_render_channels));
            std::unique_ptr<RenderDelayController> delay_controller(
                RenderDelayController::Create(EchoCanceller3Config(), rate));
            for (size_t k = 0; k < 10; ++k) {
              render_delay_buffer->Insert(render_block);
              render_delay_buffer->PrepareCaptureProcessing();

              delay_blocks = delay_controller->GetDelay(
                  render_delay_buffer->GetDownsampledRenderBuffer(),
                  render_delay_buffer->Delay(), capture_block);
            }
            EXPECT_TRUE(delay_blocks);
            EXPECT_FALSE(delay_blocks->delay);
          }
        }
      }
    }
  }
}

// Verifies that the RenderDelayController is able to align the signals for
// simple timeshifts between the signals.
TEST(RenderDelayController, Alignment) {
  Random random_generator(42U);
  for (size_t num_capture_channels : {1, 2, 4}) {
    std::vector<std::vector<float>> capture_block(
        num_capture_channels, std::vector<float>(kBlockSize, 0.f));
    for (size_t num_matched_filters = 4; num_matched_filters == 10;
         num_matched_filters++) {
      for (auto down_sampling_factor : kDownSamplingFactors) {
        EchoCanceller3Config config;
        config.delay.down_sampling_factor = down_sampling_factor;
        config.delay.num_filters = num_matched_filters;

        for (size_t num_render_channels : {1, 2, 8}) {
          for (auto rate : {16000, 32000, 48000}) {
            std::vector<std::vector<std::vector<float>>> render_block(
                NumBandsForRate(rate),
                std::vector<std::vector<float>>(
                    num_render_channels, std::vector<float>(kBlockSize, 0.f)));

            for (size_t delay_samples : {15, 50, 150, 200, 800, 4000}) {
              absl::optional<DelayEstimate> delay_blocks;
              SCOPED_TRACE(ProduceDebugText(rate, delay_samples));
              std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
                  RenderDelayBuffer::Create(config, rate, num_render_channels));
              std::unique_ptr<RenderDelayController> delay_controller(
                  RenderDelayController::Create(config, rate));
              DelayBuffer<float> signal_delay_buffer(delay_samples);
              for (size_t k = 0; k < (400 + delay_samples / kBlockSize); ++k) {
                for (size_t band = 0; band < render_block.size(); ++band) {
                  for (size_t channel = 0; channel < render_block[band].size();
                       ++channel) {
                    RandomizeSampleVector(&random_generator,
                                          render_block[band][channel]);
                  }
                }
                signal_delay_buffer.Delay(render_block[0][0], capture_block[0]);
                render_delay_buffer->Insert(render_block);
                render_delay_buffer->PrepareCaptureProcessing();
                delay_blocks = delay_controller->GetDelay(
                    render_delay_buffer->GetDownsampledRenderBuffer(),
                    render_delay_buffer->Delay(), capture_block);
              }
              ASSERT_TRUE(!!delay_blocks);

              constexpr int kDelayHeadroomBlocks = 1;
              size_t expected_delay_blocks =
                  std::max(0, static_cast<int>(delay_samples / kBlockSize) -
                                  kDelayHeadroomBlocks);

              EXPECT_EQ(expected_delay_blocks, delay_blocks->delay);
            }
          }
        }
      }
    }
  }
}

// Verifies that the RenderDelayController is able to properly handle noncausal
// delays.
TEST(RenderDelayController, NonCausalAlignment) {
  Random random_generator(42U);
  for (size_t num_capture_channels : {1, 2, 4}) {
    for (size_t num_render_channels : {1, 2, 8}) {
      for (size_t num_matched_filters = 4; num_matched_filters == 10;
           num_matched_filters++) {
        for (auto down_sampling_factor : kDownSamplingFactors) {
          EchoCanceller3Config config;
          config.delay.down_sampling_factor = down_sampling_factor;
          config.delay.num_filters = num_matched_filters;
          for (auto rate : {16000, 32000, 48000}) {
            std::vector<std::vector<std::vector<float>>> render_block(
                NumBandsForRate(rate),
                std::vector<std::vector<float>>(
                    num_render_channels, std::vector<float>(kBlockSize, 0.f)));
            std::vector<std::vector<std::vector<float>>> capture_block(
                NumBandsForRate(rate),
                std::vector<std::vector<float>>(
                    num_capture_channels, std::vector<float>(kBlockSize, 0.f)));

            for (int delay_samples : {-15, -50, -150, -200}) {
              absl::optional<DelayEstimate> delay_blocks;
              SCOPED_TRACE(ProduceDebugText(rate, -delay_samples));
              std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
                  RenderDelayBuffer::Create(config, rate, num_render_channels));
              std::unique_ptr<RenderDelayController> delay_controller(
                  RenderDelayController::Create(EchoCanceller3Config(), rate));
              DelayBuffer<float> signal_delay_buffer(-delay_samples);
              for (int k = 0;
                   k < (400 - delay_samples / static_cast<int>(kBlockSize));
                   ++k) {
                RandomizeSampleVector(&random_generator, capture_block[0][0]);
                signal_delay_buffer.Delay(capture_block[0][0],
                                          render_block[0][0]);
                render_delay_buffer->Insert(render_block);
                render_delay_buffer->PrepareCaptureProcessing();
                delay_blocks = delay_controller->GetDelay(
                    render_delay_buffer->GetDownsampledRenderBuffer(),
                    render_delay_buffer->Delay(), capture_block[0]);
              }

              ASSERT_FALSE(delay_blocks);
            }
          }
        }
      }
    }
  }
}

// Verifies that the RenderDelayController is able to align the signals for
// simple timeshifts between the signals when there is jitter in the API calls.
TEST(RenderDelayController, AlignmentWithJitter) {
  Random random_generator(42U);
  for (size_t num_capture_channels : {1, 2, 4}) {
    for (size_t num_render_channels : {1, 2, 8}) {
      std::vector<std::vector<float>> capture_block(
          num_capture_channels, std::vector<float>(kBlockSize, 0.f));
      for (size_t num_matched_filters = 4; num_matched_filters == 10;
           num_matched_filters++) {
        for (auto down_sampling_factor : kDownSamplingFactors) {
          EchoCanceller3Config config;
          config.delay.down_sampling_factor = down_sampling_factor;
          config.delay.num_filters = num_matched_filters;
          for (auto rate : {16000, 32000, 48000}) {
            std::vector<std::vector<std::vector<float>>> render_block(
                NumBandsForRate(rate),
                std::vector<std::vector<float>>(
                    num_render_channels, std::vector<float>(kBlockSize, 0.f)));
            for (size_t delay_samples : {15, 50, 300, 800}) {
              absl::optional<DelayEstimate> delay_blocks;
              SCOPED_TRACE(ProduceDebugText(rate, delay_samples));
              std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
                  RenderDelayBuffer::Create(config, rate, num_render_channels));
              std::unique_ptr<RenderDelayController> delay_controller(
                  RenderDelayController::Create(config, rate));
              DelayBuffer<float> signal_delay_buffer(delay_samples);
              constexpr size_t kMaxTestJitterBlocks = 26;
              for (size_t j = 0; j < (1000 + delay_samples / kBlockSize) /
                                             kMaxTestJitterBlocks +
                                         1;
                   ++j) {
                std::vector<std::vector<std::vector<float>>>
                    capture_block_buffer;
                for (size_t k = 0; k < (kMaxTestJitterBlocks - 1); ++k) {
                  RandomizeSampleVector(&random_generator, render_block[0][0]);
                  signal_delay_buffer.Delay(render_block[0][0],
                                            capture_block[0]);
                  capture_block_buffer.push_back(capture_block);
                  render_delay_buffer->Insert(render_block);
                }
                for (size_t k = 0; k < (kMaxTestJitterBlocks - 1); ++k) {
                  render_delay_buffer->PrepareCaptureProcessing();
                  delay_blocks = delay_controller->GetDelay(
                      render_delay_buffer->GetDownsampledRenderBuffer(),
                      render_delay_buffer->Delay(), capture_block_buffer[k]);
                }
              }

              constexpr int kDelayHeadroomBlocks = 1;
              size_t expected_delay_blocks =
                  std::max(0, static_cast<int>(delay_samples / kBlockSize) -
                                  kDelayHeadroomBlocks);
              if (expected_delay_blocks < 2) {
                expected_delay_blocks = 0;
              }

              ASSERT_TRUE(delay_blocks);
              EXPECT_EQ(expected_delay_blocks, delay_blocks->delay);
            }
          }
        }
      }
    }
  }
}

#if RTC_DCHECK_IS_ON && GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)

// Verifies the check for the capture signal block size.
TEST(RenderDelayController, WrongCaptureSize) {
  std::vector<std::vector<float>> block(
      1, std::vector<float>(kBlockSize - 1, 0.f));
  EchoCanceller3Config config;
  for (auto rate : {16000, 32000, 48000}) {
    SCOPED_TRACE(ProduceDebugText(rate));
    std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
        RenderDelayBuffer::Create(config, rate, 1));
    EXPECT_DEATH(
        std::unique_ptr<RenderDelayController>(
            RenderDelayController::Create(EchoCanceller3Config(), rate))
            ->GetDelay(render_delay_buffer->GetDownsampledRenderBuffer(),
                       render_delay_buffer->Delay(), block),
        "");
  }
}

// Verifies the check for correct sample rate.
// TODO(peah): Re-enable the test once the issue with memory leaks during DEATH
// tests on test bots has been fixed.
TEST(RenderDelayController, DISABLED_WrongSampleRate) {
  for (auto rate : {-1, 0, 8001, 16001}) {
    SCOPED_TRACE(ProduceDebugText(rate));
    EchoCanceller3Config config;
    std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
        RenderDelayBuffer::Create(config, rate, 1));
    EXPECT_DEATH(
        std::unique_ptr<RenderDelayController>(
            RenderDelayController::Create(EchoCanceller3Config(), rate)),
        "");
  }
}

#endif

}  // namespace webrtc