/*
 *  Copyright (c) 2013 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/transient/transient_detector.h"

#include <sstream>
#include <string>

#include "testing/gtest/include/gtest/gtest.h"
#include "webrtc/modules/audio_processing/transient/common.h"
#include "webrtc/modules/audio_processing/transient/file_utils.h"
#include "webrtc/system_wrappers/interface/file_wrapper.h"
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
#include "webrtc/test/testsupport/fileutils.h"
#include "webrtc/typedefs.h"

namespace webrtc {

static const int kSampleRatesHz[] = {ts::kSampleRate8kHz,
                                     ts::kSampleRate16kHz,
                                     ts::kSampleRate32kHz,
                                     ts::kSampleRate48kHz};
static const size_t kNumberOfSampleRates =
    sizeof(kSampleRatesHz) / sizeof(*kSampleRatesHz);

// This test is for the correctness of the transient detector.
// Checks the results comparing them with the ones stored in the detect files in
// the directory: resources/audio_processing/transient/
// The files contain all the results in double precision (Little endian).
// The audio files used with different sample rates are stored in the same
// directory.
TEST(TransientDetectorTest, CorrectnessBasedOnFiles) {
  for (size_t i = 0; i < kNumberOfSampleRates; ++i) {
    int sample_rate_hz = kSampleRatesHz[i];

    // Prepare detect file.
    std::stringstream detect_file_name;
    detect_file_name << "audio_processing/transient/detect"
                     << (sample_rate_hz / 1000) << "kHz";

    scoped_ptr<FileWrapper> detect_file(FileWrapper::Create());

    detect_file->OpenFile(
        test::ResourcePath(detect_file_name.str(), "dat").c_str(),
        true,    // Read only.
        false,   // No loop.
        false);  // No text.

    bool file_opened = detect_file->Open();
    ASSERT_TRUE(file_opened) << "File could not be opened.\n"
          << detect_file_name.str().c_str();

    // Prepare audio file.
    std::stringstream audio_file_name;
    audio_file_name << "audio_processing/transient/audio"
                    << (sample_rate_hz / 1000) << "kHz";

    scoped_ptr<FileWrapper> audio_file(FileWrapper::Create());

    audio_file->OpenFile(
        test::ResourcePath(audio_file_name.str(), "pcm").c_str(),
        true,    // Read only.
        false,   // No loop.
        false);  // No text.

    // Create detector.
    TransientDetector detector(sample_rate_hz);

    const size_t buffer_length = sample_rate_hz * ts::kChunkSizeMs / 1000;
    scoped_ptr<float[]> buffer(new float[buffer_length]);

    const float kTolerance = 0.02f;

    size_t frames_read = 0;

    while (ReadInt16FromFileToFloatBuffer(audio_file.get(),
                                          buffer_length,
                                          buffer.get()) == buffer_length) {
      ++frames_read;

      float detector_value =
          detector.Detect(buffer.get(), buffer_length, NULL, 0);
      double file_value;
      ASSERT_EQ(1u, ReadDoubleBufferFromFile(detect_file.get(), 1, &file_value))
          << "Detect test file is malformed.\n";

      // Compare results with data from the matlab test file.
      EXPECT_NEAR(file_value, detector_value, kTolerance) << "Frame: "
          << frames_read;
    }

    detect_file->CloseFile();
    audio_file->CloseFile();
  }
}

}  // namespace webrtc
