/*
 *  Copyright (c) 2012 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 "webrtc/modules/audio_processing/agc/pole_zero_filter.h"

#include <math.h>
#include <stdio.h>

#include "gtest/gtest.h"
#include "webrtc/base/compile_assert.h"
#include "webrtc/modules/audio_processing/agc/agc_audio_proc_internal.h"
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
#include "webrtc/test/testsupport/fileutils.h"

namespace webrtc {

static const int kInputSamples = 50;

static const int16_t kInput[kInputSamples] = {-2136, -7116, 10715, 2464, 3164,
    8139, 11393, 24013, -32117, -5544, -27740, 10181, 14190, -24055, -15912,
    17393, 6359, -9950, -13894, 32432, -23944, 3437, -8381, 19768, 3087, -19795,
    -5920, 13310, 1407, 3876, 4059, 3524, -23130, 19121, -27900, -24840, 4089,
    21422, -3625, 3015, -11236, 28856, 13424, 6571, -19761, -6361, 15821, -9469,
    29727, 32229};

static const float kReferenceOutput[kInputSamples] = {-2082.230472f,
    -6878.572941f, 10697.090871f, 2358.373952f, 2973.936512f, 7738.580650f,
    10690.803213f, 22687.091576f, -32676.684717f, -5879.621684f, -27359.297432f,
    10368.735888f, 13994.584604f, -23676.126249f, -15078.250390f, 17818.253338f,
    6577.743123f,  -9498.369315f, -13073.651079f, 32460.026588f, -23391.849347f,
    3953.805667f, -7667.761363f, 19995.153447f, 3185.575477f, -19207.365160f,
    -5143.103201f, 13756.317237f, 1779.654794f, 4142.269755f, 4209.475034f,
    3572.991789f, -22509.089546f, 19307.878964f, -27060.439759f, -23319.042810f,
    5547.685267f, 22312.718676f, -2707.309027f, 3852.358490f, -10135.510093f,
    29241.509970f, 13394.397233f, 6340.721417f, -19510.207905f, -5908.442086f,
    15882.301634f, -9211.335255f, 29253.056735f, 30874.443046f};

class PoleZeroFilterTest : public ::testing::Test {
 protected:
  PoleZeroFilterTest()
     : my_filter_(PoleZeroFilter::Create(
         kCoeffNumerator, kFilterOrder, kCoeffDenominator, kFilterOrder)) {}

  ~PoleZeroFilterTest() {}

  void FilterSubframes(int num_subframes);

 private:
  void TestClean();
  scoped_ptr<PoleZeroFilter> my_filter_;
};

void PoleZeroFilterTest::FilterSubframes(int num_subframes) {
  float output[kInputSamples];
  const int num_subframe_samples = kInputSamples / num_subframes;
  EXPECT_EQ(num_subframe_samples * num_subframes, kInputSamples);

  for (int n = 0; n < num_subframes; n++) {
    my_filter_->Filter(&kInput[n * num_subframe_samples], num_subframe_samples,
                       &output[n * num_subframe_samples]);
  }
  for (int n = 0; n < kInputSamples; n++) {
    EXPECT_NEAR(output[n], kReferenceOutput[n], 1);
  }
}

TEST_F(PoleZeroFilterTest, OneSubframe) {
  FilterSubframes(1);
}

TEST_F(PoleZeroFilterTest, TwoSubframes) {
  FilterSubframes(2);
}

TEST_F(PoleZeroFilterTest, FiveSubframes) {
  FilterSubframes(5);
}

TEST_F(PoleZeroFilterTest, TenSubframes) {
  FilterSubframes(10);
}

TEST_F(PoleZeroFilterTest, TwentyFiveSubframes) {
  FilterSubframes(25);
}

TEST_F(PoleZeroFilterTest, FiftySubframes) {
  FilterSubframes(50);
}

}  // namespace webrtc