/*
 *  Copyright (c) 2012 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 "./vpx_config.h"
#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"
#include "test/y4m_video_source.h"

namespace {

class DatarateTest : public ::libvpx_test::EncoderTest,
    public ::libvpx_test::CodecTestWithParam<libvpx_test::TestMode> {
 public:
  DatarateTest() : EncoderTest(GET_PARAM(0)) {}

 protected:
  virtual void SetUp() {
    InitializeConfig();
    SetMode(GET_PARAM(1));
    ResetModel();
  }

  virtual void ResetModel() {
    last_pts_ = 0;
    bits_in_buffer_model_ = cfg_.rc_target_bitrate * cfg_.rc_buf_initial_sz;
    frame_number_ = 0;
    first_drop_ = 0;
    bits_total_ = 0;
    duration_ = 0.0;
  }

  virtual void PreEncodeFrameHook(::libvpx_test::VideoSource *video,
                                  ::libvpx_test::Encoder *encoder) {
    const vpx_rational_t tb = video->timebase();
    timebase_ = static_cast<double>(tb.num) / tb.den;
    duration_ = 0;
  }

  virtual void FramePktHook(const vpx_codec_cx_pkt_t *pkt) {
    // Time since last timestamp = duration.
    vpx_codec_pts_t duration = pkt->data.frame.pts - last_pts_;

    // TODO(jimbankoski): Remove these lines when the issue:
    // http://code.google.com/p/webm/issues/detail?id=496 is fixed.
    // For now the codec assumes buffer starts at starting buffer rate
    // plus one frame's time.
    if (last_pts_ == 0)
      duration = 1;

    // Add to the buffer the bits we'd expect from a constant bitrate server.
    bits_in_buffer_model_ += static_cast<int64_t>(
        duration * timebase_ * cfg_.rc_target_bitrate * 1000);

    /* Test the buffer model here before subtracting the frame. Do so because
     * the way the leaky bucket model works in libvpx is to allow the buffer to
     * empty - and then stop showing frames until we've got enough bits to
     * show one. As noted in comment below (issue 495), this does not currently
     * apply to key frames. For now exclude key frames in condition below. */
    const bool key_frame = (pkt->data.frame.flags & VPX_FRAME_IS_KEY)
                         ? true: false;
    if (!key_frame) {
      ASSERT_GE(bits_in_buffer_model_, 0) << "Buffer Underrun at frame "
          << pkt->data.frame.pts;
    }

    const size_t frame_size_in_bits = pkt->data.frame.sz * 8;

    // Subtract from the buffer the bits associated with a played back frame.
    bits_in_buffer_model_ -= frame_size_in_bits;

    // Update the running total of bits for end of test datarate checks.
    bits_total_ += frame_size_in_bits;

    // If first drop not set and we have a drop set it to this time.
    if (!first_drop_ && duration > 1)
      first_drop_ = last_pts_ + 1;

    // Update the most recent pts.
    last_pts_ = pkt->data.frame.pts;

    // We update this so that we can calculate the datarate minus the last
    // frame encoded in the file.
    bits_in_last_frame_ = frame_size_in_bits;

    ++frame_number_;
  }

  virtual void EndPassHook(void) {
    if (bits_total_) {
      const double file_size_in_kb = bits_total_ / 1000.;  // bits per kilobit

      duration_ = (last_pts_ + 1) * timebase_;

      // Effective file datarate includes the time spent prebuffering.
      effective_datarate_ = (bits_total_ - bits_in_last_frame_) / 1000.0
          / (cfg_.rc_buf_initial_sz / 1000.0 + duration_);

      file_datarate_ = file_size_in_kb / duration_;
    }
  }

  vpx_codec_pts_t last_pts_;
  int64_t bits_in_buffer_model_;
  double timebase_;
  int frame_number_;
  vpx_codec_pts_t first_drop_;
  int64_t bits_total_;
  double duration_;
  double file_datarate_;
  double effective_datarate_;
  size_t bits_in_last_frame_;
};

TEST_P(DatarateTest, BasicBufferModel) {
  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_dropframe_thresh = 1;
  cfg_.rc_max_quantizer = 56;
  cfg_.rc_end_usage = VPX_CBR;
  // 2 pass cbr datarate control has a bug hidden by the small # of
  // frames selected in this encode. The problem is that even if the buffer is
  // negative we produce a keyframe on a cutscene. Ignoring datarate
  // constraints
  // TODO(jimbankoski): ( Fix when issue
  // http://code.google.com/p/webm/issues/detail?id=495 is addressed. )
  ::libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                       30, 1, 0, 140);

  // There is an issue for low bitrates in real-time mode, where the
  // effective_datarate slightly overshoots the target bitrate.
  // This is same the issue as noted about (#495).
  // TODO(jimbankoski/marpan): Update test to run for lower bitrates (< 100),
  // when the issue is resolved.
  for (int i = 100; i < 800; i += 200) {
    cfg_.rc_target_bitrate = i;
    ResetModel();
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    ASSERT_GE(cfg_.rc_target_bitrate, effective_datarate_)
        << " The datarate for the file exceeds the target!";

    ASSERT_LE(cfg_.rc_target_bitrate, file_datarate_ * 1.3)
        << " The datarate for the file missed the target!";
  }
}

TEST_P(DatarateTest, ChangingDropFrameThresh) {
  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_max_quantizer = 36;
  cfg_.rc_end_usage = VPX_CBR;
  cfg_.rc_target_bitrate = 200;
  cfg_.kf_mode = VPX_KF_DISABLED;

  const int frame_count = 40;
  ::libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                       30, 1, 0, frame_count);

  // Here we check that the first dropped frame gets earlier and earlier
  // as the drop frame threshold is increased.

  const int kDropFrameThreshTestStep = 30;
  vpx_codec_pts_t last_drop = frame_count;
  for (int i = 1; i < 91; i += kDropFrameThreshTestStep) {
    cfg_.rc_dropframe_thresh = i;
    ResetModel();
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    ASSERT_LE(first_drop_, last_drop)
        << " The first dropped frame for drop_thresh " << i
        << " > first dropped frame for drop_thresh "
        << i - kDropFrameThreshTestStep;
    last_drop = first_drop_;
  }
}

class DatarateTestVP9 : public ::libvpx_test::EncoderTest,
    public ::libvpx_test::CodecTestWith2Params<libvpx_test::TestMode, int> {
 public:
  DatarateTestVP9() : EncoderTest(GET_PARAM(0)) {}

 protected:
  virtual ~DatarateTestVP9() {}

  virtual void SetUp() {
    InitializeConfig();
    SetMode(GET_PARAM(1));
    set_cpu_used_ = GET_PARAM(2);
    ResetModel();
  }

  virtual void ResetModel() {
    last_pts_ = 0;
    bits_in_buffer_model_ = cfg_.rc_target_bitrate * cfg_.rc_buf_initial_sz;
    frame_number_ = 0;
    first_drop_ = 0;
    num_drops_ = 0;
    // For testing up to 3 layers.
    for (int i = 0; i < 3; ++i) {
      bits_total_[i] = 0;
    }
  }

  //
  // Frame flags and layer id for temporal layers.
  //

  // For two layers, test pattern is:
  //   1     3
  // 0    2     .....
  // For three layers, test pattern is:
  //   1      3    5      7
  //      2           6
  // 0          4            ....
  // LAST is always update on base/layer 0, GOLDEN is updated on layer 1.
  // For this 3 layer example, the 2nd enhancement layer (layer 2) does not
  // update any reference frames.
  int SetFrameFlags(int frame_num, int num_temp_layers) {
    int frame_flags = 0;
    if (num_temp_layers == 2) {
      if (frame_num % 2 == 0) {
        // Layer 0: predict from L and ARF, update L.
        frame_flags = VP8_EFLAG_NO_REF_GF | VP8_EFLAG_NO_UPD_GF |
                      VP8_EFLAG_NO_UPD_ARF;
      } else {
        // Layer 1: predict from L, G and ARF, and update G.
        frame_flags = VP8_EFLAG_NO_UPD_ARF | VP8_EFLAG_NO_UPD_LAST |
                      VP8_EFLAG_NO_UPD_ENTROPY;
      }
    } else if (num_temp_layers == 3) {
      if (frame_num % 4 == 0) {
        // Layer 0: predict from L and ARF; update L.
        frame_flags = VP8_EFLAG_NO_UPD_GF | VP8_EFLAG_NO_UPD_ARF |
                      VP8_EFLAG_NO_REF_GF;
      } else if ((frame_num - 2) % 4 == 0) {
        // Layer 1: predict from L, G, ARF; update G.
        frame_flags = VP8_EFLAG_NO_UPD_ARF | VP8_EFLAG_NO_UPD_LAST;
      }  else if ((frame_num - 1) % 2 == 0) {
        // Layer 2: predict from L, G, ARF; update none.
        frame_flags = VP8_EFLAG_NO_UPD_GF | VP8_EFLAG_NO_UPD_ARF |
                      VP8_EFLAG_NO_UPD_LAST;
      }
    }
    return frame_flags;
  }

  int SetLayerId(int frame_num, int num_temp_layers) {
    int layer_id = 0;
    if (num_temp_layers == 2) {
      if (frame_num % 2 == 0) {
        layer_id = 0;
      } else {
        layer_id = 1;
      }
    } else if (num_temp_layers == 3) {
      if (frame_num % 4 == 0) {
        layer_id = 0;
      } else if ((frame_num - 2) % 4 == 0) {
        layer_id = 1;
      } else if ((frame_num - 1) % 2 == 0) {
        layer_id = 2;
      }
    }
    return layer_id;
  }

  virtual void PreEncodeFrameHook(::libvpx_test::VideoSource *video,
                                  ::libvpx_test::Encoder *encoder) {
    if (video->frame() == 1) {
      encoder->Control(VP8E_SET_CPUUSED, set_cpu_used_);
    }
    if (cfg_.ts_number_layers > 1) {
      if (video->frame() == 1) {
        encoder->Control(VP9E_SET_SVC, 1);
      }
      vpx_svc_layer_id_t layer_id = {0, 0};
      layer_id.spatial_layer_id = 0;
      frame_flags_ = SetFrameFlags(video->frame(), cfg_.ts_number_layers);
      layer_id.temporal_layer_id = SetLayerId(video->frame(),
                                              cfg_.ts_number_layers);
      if (video->frame() > 0) {
       encoder->Control(VP9E_SET_SVC_LAYER_ID, &layer_id);
      }
    }
    const vpx_rational_t tb = video->timebase();
    timebase_ = static_cast<double>(tb.num) / tb.den;
    duration_ = 0;
  }


  virtual void FramePktHook(const vpx_codec_cx_pkt_t *pkt) {
    int layer = SetLayerId(frame_number_, cfg_.ts_number_layers);

    // Time since last timestamp = duration.
    vpx_codec_pts_t duration = pkt->data.frame.pts - last_pts_;

    // Add to the buffer the bits we'd expect from a constant bitrate server.
    bits_in_buffer_model_ += static_cast<int64_t>(
        duration * timebase_ * cfg_.rc_target_bitrate * 1000);

    // Buffer should not go negative.
    ASSERT_GE(bits_in_buffer_model_, 0) << "Buffer Underrun at frame "
        << pkt->data.frame.pts;

    const size_t frame_size_in_bits = pkt->data.frame.sz * 8;

    // Update the total encoded bits. For temporal layers, update the cumulative
    // encoded bits per layer.
    for (int i = layer; i < static_cast<int>(cfg_.ts_number_layers); ++i) {
      bits_total_[i] += frame_size_in_bits;
    }

    // If first drop not set and we have a drop set it to this time.
    if (!first_drop_ && duration > 1)
      first_drop_ = last_pts_ + 1;

    // Update the number of frame drops.
    if (duration > 1) {
      num_drops_ += static_cast<int>(duration - 1);
    }

    // Update the most recent pts.
    last_pts_ = pkt->data.frame.pts;
    ++frame_number_;
  }

  virtual void EndPassHook(void) {
    for (int layer = 0; layer < static_cast<int>(cfg_.ts_number_layers);
        ++layer) {
      duration_ = (last_pts_ + 1) * timebase_;
      if (bits_total_[layer]) {
        // Effective file datarate:
        effective_datarate_[layer] = (bits_total_[layer] / 1000.0) / duration_;
      }
    }
  }

  vpx_codec_pts_t last_pts_;
  double timebase_;
  int frame_number_;
  int64_t bits_total_[3];
  double duration_;
  double effective_datarate_[3];
  int set_cpu_used_;
  int64_t bits_in_buffer_model_;
  vpx_codec_pts_t first_drop_;
  int num_drops_;
};

// Check basic rate targeting,
TEST_P(DatarateTestVP9, BasicRateTargeting) {
  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_buf_optimal_sz = 500;
  cfg_.rc_buf_sz = 1000;
  cfg_.rc_dropframe_thresh = 1;
  cfg_.rc_min_quantizer = 0;
  cfg_.rc_max_quantizer = 63;
  cfg_.rc_end_usage = VPX_CBR;
  cfg_.g_lag_in_frames = 0;

  ::libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                       30, 1, 0, 140);
  for (int i = 150; i < 800; i += 200) {
    cfg_.rc_target_bitrate = i;
    ResetModel();
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    ASSERT_GE(effective_datarate_[0], cfg_.rc_target_bitrate * 0.85)
        << " The datarate for the file is lower than target by too much!";
    ASSERT_LE(effective_datarate_[0], cfg_.rc_target_bitrate * 1.15)
        << " The datarate for the file is greater than target by too much!";
  }
}

#if CONFIG_NON420
// Check basic rate targeting,
TEST_P(DatarateTestVP9, BasicRateTargeting444) {
  ::libvpx_test::Y4mVideoSource video("rush_hour_444.y4m", 0, 140);

  cfg_.g_profile = 1;
  cfg_.g_timebase = video.timebase();

  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_buf_optimal_sz = 500;
  cfg_.rc_buf_sz = 1000;
  cfg_.rc_dropframe_thresh = 1;
  cfg_.rc_min_quantizer = 0;
  cfg_.rc_max_quantizer = 63;
  cfg_.rc_end_usage = VPX_CBR;

  for (int i = 250; i < 900; i += 200) {
    cfg_.rc_target_bitrate = i;
    ResetModel();
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    ASSERT_GE(static_cast<double>(cfg_.rc_target_bitrate),
              effective_datarate_[0] * 0.85)
        << " The datarate for the file exceeds the target by too much!";
    ASSERT_LE(static_cast<double>(cfg_.rc_target_bitrate),
              effective_datarate_[0] * 1.15)
        << " The datarate for the file missed the target!"
        << cfg_.rc_target_bitrate << " "<< effective_datarate_;
  }
}
#endif

// Check that (1) the first dropped frame gets earlier and earlier
// as the drop frame threshold is increased, and (2) that the total number of
// frame drops does not decrease as we increase frame drop threshold.
// Use a lower qp-max to force some frame drops.
TEST_P(DatarateTestVP9, ChangingDropFrameThresh) {
  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_buf_optimal_sz = 500;
  cfg_.rc_buf_sz = 1000;
  cfg_.rc_undershoot_pct = 20;
  cfg_.rc_undershoot_pct = 20;
  cfg_.rc_dropframe_thresh = 10;
  cfg_.rc_min_quantizer = 0;
  cfg_.rc_max_quantizer = 50;
  cfg_.rc_end_usage = VPX_CBR;
  cfg_.rc_target_bitrate = 200;
  cfg_.g_lag_in_frames = 0;

  ::libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                       30, 1, 0, 140);

  const int kDropFrameThreshTestStep = 30;
  vpx_codec_pts_t last_drop = 140;
  int last_num_drops = 0;
  for (int i = 10; i < 100; i += kDropFrameThreshTestStep) {
    cfg_.rc_dropframe_thresh = i;
    ResetModel();
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    ASSERT_GE(effective_datarate_[0], cfg_.rc_target_bitrate * 0.85)
        << " The datarate for the file is lower than target by too much!";
    ASSERT_LE(effective_datarate_[0], cfg_.rc_target_bitrate * 1.15)
        << " The datarate for the file is greater than target by too much!";
    ASSERT_LE(first_drop_, last_drop)
        << " The first dropped frame for drop_thresh " << i
        << " > first dropped frame for drop_thresh "
        << i - kDropFrameThreshTestStep;
    ASSERT_GE(num_drops_, last_num_drops)
        << " The number of dropped frames for drop_thresh " << i
        << " < number of dropped frames for drop_thresh "
        << i - kDropFrameThreshTestStep;
    last_drop = first_drop_;
    last_num_drops = num_drops_;
  }
}

// Check basic rate targeting for 2 temporal layers.
TEST_P(DatarateTestVP9, BasicRateTargeting2TemporalLayers) {
  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_buf_optimal_sz = 500;
  cfg_.rc_buf_sz = 1000;
  cfg_.rc_dropframe_thresh = 1;
  cfg_.rc_min_quantizer = 0;
  cfg_.rc_max_quantizer = 63;
  cfg_.rc_end_usage = VPX_CBR;
  cfg_.g_lag_in_frames = 0;

  // 2 Temporal layers, no spatial layers: Framerate decimation (2, 1).
  cfg_.ss_number_layers = 1;
  cfg_.ts_number_layers = 2;
  cfg_.ts_rate_decimator[0] = 2;
  cfg_.ts_rate_decimator[1] = 1;

  ::libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                       30, 1, 0, 200);
  for (int i = 200; i <= 800; i += 200) {
    cfg_.rc_target_bitrate = i;
    ResetModel();
    // 60-40 bitrate allocation for 2 temporal layers.
    cfg_.ts_target_bitrate[0] = 60 * cfg_.rc_target_bitrate / 100;
    cfg_.ts_target_bitrate[1] = cfg_.rc_target_bitrate;
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    for (int j = 0; j < static_cast<int>(cfg_.ts_number_layers); ++j) {
      ASSERT_GE(effective_datarate_[j], cfg_.ts_target_bitrate[j] * 0.85)
          << " The datarate for the file is lower than target by too much, "
              "for layer: " << j;
      ASSERT_LE(effective_datarate_[j], cfg_.ts_target_bitrate[j] * 1.15)
          << " The datarate for the file is greater than target by too much, "
              "for layer: " << j;
    }
  }
}

// Check basic rate targeting for 3 temporal layers.
TEST_P(DatarateTestVP9, BasicRateTargeting3TemporalLayers) {
  cfg_.rc_buf_initial_sz = 500;
  cfg_.rc_buf_optimal_sz = 500;
  cfg_.rc_buf_sz = 1000;
  // TODO(marpan): For now keep frame dropper off. Need to investigate an
  // issue (rate-mismatch) that occcurs at speed 3 and low bitrate (200k) when
  // frame dropper is on.
  cfg_.rc_dropframe_thresh = 0;
  cfg_.rc_min_quantizer = 0;
  cfg_.rc_max_quantizer = 63;
  cfg_.rc_end_usage = VPX_CBR;
  cfg_.g_lag_in_frames = 0;

  // 3 Temporal layers, no spatial layers: Framerate decimation (4, 2, 1).
  cfg_.ss_number_layers = 1;
  cfg_.ts_number_layers = 3;
  cfg_.ts_rate_decimator[0] = 4;
  cfg_.ts_rate_decimator[1] = 2;
  cfg_.ts_rate_decimator[2] = 1;

  ::libvpx_test::I420VideoSource video("hantro_collage_w352h288.yuv", 352, 288,
                                       30, 1, 0, 200);
  for (int i = 200; i <= 800; i += 200) {
    cfg_.rc_target_bitrate = i;
    ResetModel();
    // 40-20-40 bitrate allocation for 3 temporal layers.
    cfg_.ts_target_bitrate[0] = 40 * cfg_.rc_target_bitrate / 100;
    cfg_.ts_target_bitrate[1] = 60 * cfg_.rc_target_bitrate / 100;
    cfg_.ts_target_bitrate[2] = cfg_.rc_target_bitrate;
    ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
    for (int j = 0; j < static_cast<int>(cfg_.ts_number_layers); ++j) {
      ASSERT_GE(effective_datarate_[j], cfg_.ts_target_bitrate[j] * 0.85)
          << " The datarate for the file is lower than target by too much, "
              "for layer: " << j;
      ASSERT_LE(effective_datarate_[j], cfg_.ts_target_bitrate[j] * 1.15)
          << " The datarate for the file is greater than target by too much, "
              "for layer: " << j;
    }
  }
}
VP8_INSTANTIATE_TEST_CASE(DatarateTest, ALL_TEST_MODES);
VP9_INSTANTIATE_TEST_CASE(DatarateTestVP9,
                          ::testing::Values(::libvpx_test::kOnePassGood),
                          ::testing::Range(1, 5));
}  // namespace