/*
 *  Copyright (c) 2013 The WebM 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 "third_party/googletest/src/include/gtest/gtest.h"
#include "test/codec_factory.h"
#include "test/encode_test_driver.h"
#include "test/i420_video_source.h"
#include "test/util.h"

namespace {

const int kMaxErrorFrames = 12;
const int kMaxDroppableFrames = 12;

class ErrorResilienceTest : public ::libvpx_test::EncoderTest,
    public ::libvpx_test::CodecTestWithParam<libvpx_test::TestMode> {
 protected:
  ErrorResilienceTest() : EncoderTest(GET_PARAM(0)),
                          psnr_(0.0),
                          nframes_(0),
                          mismatch_psnr_(0.0),
                          mismatch_nframes_(0),
                          encoding_mode_(GET_PARAM(1)) {
    Reset();
  }

  virtual ~ErrorResilienceTest() {}

  void Reset() {
    error_nframes_ = 0;
    droppable_nframes_ = 0;
  }

  virtual void SetUp() {
    InitializeConfig();
    SetMode(encoding_mode_);
  }

  virtual void BeginPassHook(unsigned int /*pass*/) {
    psnr_ = 0.0;
    nframes_ = 0;
    mismatch_psnr_ = 0.0;
    mismatch_nframes_ = 0;
  }

  virtual void PSNRPktHook(const vpx_codec_cx_pkt_t *pkt) {
    psnr_ += pkt->data.psnr.psnr[0];
    nframes_++;
  }

  virtual void PreEncodeFrameHook(libvpx_test::VideoSource *video) {
    frame_flags_ &= ~(VP8_EFLAG_NO_UPD_LAST |
                      VP8_EFLAG_NO_UPD_GF |
                      VP8_EFLAG_NO_UPD_ARF);
    if (droppable_nframes_ > 0 &&
        (cfg_.g_pass == VPX_RC_LAST_PASS || cfg_.g_pass == VPX_RC_ONE_PASS)) {
      for (unsigned int i = 0; i < droppable_nframes_; ++i) {
        if (droppable_frames_[i] == video->frame()) {
          std::cout << "             Encoding droppable frame: "
                    << droppable_frames_[i] << "\n";
          frame_flags_ |= (VP8_EFLAG_NO_UPD_LAST |
                           VP8_EFLAG_NO_UPD_GF |
                           VP8_EFLAG_NO_UPD_ARF);
          return;
        }
      }
    }
  }

  double GetAveragePsnr() const {
    if (nframes_)
      return psnr_ / nframes_;
    return 0.0;
  }

  double GetAverageMismatchPsnr() const {
    if (mismatch_nframes_)
      return mismatch_psnr_ / mismatch_nframes_;
    return 0.0;
  }

  virtual bool DoDecode() const {
    if (error_nframes_ > 0 &&
        (cfg_.g_pass == VPX_RC_LAST_PASS || cfg_.g_pass == VPX_RC_ONE_PASS)) {
      for (unsigned int i = 0; i < error_nframes_; ++i) {
        if (error_frames_[i] == nframes_ - 1) {
          std::cout << "             Skipping decoding frame: "
                    << error_frames_[i] << "\n";
          return 0;
        }
      }
    }
    return 1;
  }

  virtual void MismatchHook(const vpx_image_t *img1,
                            const vpx_image_t *img2) {
    double mismatch_psnr = compute_psnr(img1, img2);
    mismatch_psnr_ += mismatch_psnr;
    ++mismatch_nframes_;
    // std::cout << "Mismatch frame psnr: " << mismatch_psnr << "\n";
  }

  void SetErrorFrames(int num, unsigned int *list) {
    if (num > kMaxErrorFrames)
      num = kMaxErrorFrames;
    else if (num < 0)
      num = 0;
    error_nframes_ = num;
    for (unsigned int i = 0; i < error_nframes_; ++i)
      error_frames_[i] = list[i];
  }

  void SetDroppableFrames(int num, unsigned int *list) {
    if (num > kMaxDroppableFrames)
      num = kMaxDroppableFrames;
    else if (num < 0)
      num = 0;
    droppable_nframes_ = num;
    for (unsigned int i = 0; i < droppable_nframes_; ++i)
      droppable_frames_[i] = list[i];
  }

  unsigned int GetMismatchFrames() {
    return mismatch_nframes_;
  }

 private:
  double psnr_;
  unsigned int nframes_;
  unsigned int error_nframes_;
  unsigned int droppable_nframes_;
  double mismatch_psnr_;
  unsigned int mismatch_nframes_;
  unsigned int error_frames_[kMaxErrorFrames];
  unsigned int droppable_frames_[kMaxDroppableFrames];
  libvpx_test::TestMode encoding_mode_;
};

TEST_P(ErrorResilienceTest, OnVersusOff) {
  const vpx_rational timebase = { 33333333, 1000000000 };
  cfg_.g_timebase = timebase;
  cfg_.rc_target_bitrate = 2000;
  cfg_.g_lag_in_frames = 10;

  init_flags_ = VPX_CODEC_USE_PSNR;

  libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                     timebase.den, timebase.num, 0, 30);

  // Error resilient mode OFF.
  cfg_.g_error_resilient = 0;
  ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
  const double psnr_resilience_off = GetAveragePsnr();
  EXPECT_GT(psnr_resilience_off, 25.0);

  // Error resilient mode ON.
  cfg_.g_error_resilient = 1;
  ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
  const double psnr_resilience_on = GetAveragePsnr();
  EXPECT_GT(psnr_resilience_on, 25.0);

  // Test that turning on error resilient mode hurts by 10% at most.
  if (psnr_resilience_off > 0.0) {
    const double psnr_ratio = psnr_resilience_on / psnr_resilience_off;
    EXPECT_GE(psnr_ratio, 0.9);
    EXPECT_LE(psnr_ratio, 1.1);
  }
}

// Check for successful decoding and no encoder/decoder mismatch
// if we lose (i.e., drop before decoding) a set of droppable
// frames (i.e., frames that don't update any reference buffers).
// Check both isolated and consecutive loss.
TEST_P(ErrorResilienceTest, DropFramesWithoutRecovery) {
  const vpx_rational timebase = { 33333333, 1000000000 };
  cfg_.g_timebase = timebase;
  cfg_.rc_target_bitrate = 500;
  // FIXME(debargha): Fix this to work for any lag.
  // Currently this test only works for lag = 0
  cfg_.g_lag_in_frames = 0;

  init_flags_ = VPX_CODEC_USE_PSNR;

  libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                     timebase.den, timebase.num, 0, 40);

  // Error resilient mode ON.
  cfg_.g_error_resilient = 1;
  cfg_.kf_mode = VPX_KF_DISABLED;

  // Set an arbitrary set of error frames same as droppable frames.
  // In addition to isolated loss/drop, add a long consecutive series
  // (of size 9) of dropped frames.
  unsigned int num_droppable_frames = 11;
  unsigned int droppable_frame_list[] = {5, 16, 22, 23, 24, 25, 26, 27, 28,
                                         29, 30};
  SetDroppableFrames(num_droppable_frames, droppable_frame_list);
  SetErrorFrames(num_droppable_frames, droppable_frame_list);
  ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
  // Test that no mismatches have been found
  std::cout << "             Mismatch frames: "
            << GetMismatchFrames() << "\n";
  EXPECT_EQ(GetMismatchFrames(), (unsigned int) 0);

  // Reset previously set of error/droppable frames.
  Reset();

#if 0
  // TODO(jkoleszar): This test is disabled for the time being as too
  // sensitive. It's not clear how to set a reasonable threshold for
  // this behavior.

  // Now set an arbitrary set of error frames that are non-droppable
  unsigned int num_error_frames = 3;
  unsigned int error_frame_list[] = {3, 10, 20};
  SetErrorFrames(num_error_frames, error_frame_list);
  ASSERT_NO_FATAL_FAILURE(RunLoop(&video));

  // Test that dropping an arbitrary set of inter frames does not hurt too much
  // Note the Average Mismatch PSNR is the average of the PSNR between
  // decoded frame and encoder's version of the same frame for all frames
  // with mismatch.
  const double psnr_resilience_mismatch = GetAverageMismatchPsnr();
  std::cout << "             Mismatch PSNR: "
            << psnr_resilience_mismatch << "\n";
  EXPECT_GT(psnr_resilience_mismatch, 20.0);
#endif
}

VP8_INSTANTIATE_TEST_CASE(ErrorResilienceTest, ONE_PASS_TEST_MODES);
VP9_INSTANTIATE_TEST_CASE(ErrorResilienceTest, ONE_PASS_TEST_MODES);

}  // namespace