/*
 * Copyright (c) 2016, Alliance for Open Media. All rights reserved
 *
 * This source code is subject to the terms of the BSD 2 Clause License and
 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
 * was not distributed with this source code in the LICENSE file, you can
 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
 * Media Patent License 1.0 was not distributed with this source code in the
 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
 */

#include <math.h>
#include <stdlib.h>
#include <string.h>

#include "third_party/googletest/src/googletest/include/gtest/gtest.h"

#include "./av1_rtcd.h"
#include "./aom_config.h"
#include "./aom_dsp_rtcd.h"
#include "test/acm_random.h"
#include "test/clear_system_state.h"
#include "test/register_state_check.h"
#include "test/util.h"
#include "av1/common/entropy.h"
#include "aom/aom_codec.h"
#include "aom/aom_integer.h"
#include "aom_ports/mem.h"
#include "aom_ports/msvc.h"  // for round()

using libaom_test::ACMRandom;

namespace {

const int kNumCoeffs = 1024;
const double kPi = 3.141592653589793238462643383279502884;
void reference_32x32_dct_1d(const double in[32], double out[32]) {
  const double kInvSqrt2 = 0.707106781186547524400844362104;
  for (int k = 0; k < 32; k++) {
    out[k] = 0.0;
    for (int n = 0; n < 32; n++)
      out[k] += in[n] * cos(kPi * (2 * n + 1) * k / 64.0);
    if (k == 0) out[k] = out[k] * kInvSqrt2;
  }
}

void reference_32x32_dct_2d(const int16_t input[kNumCoeffs],
                            double output[kNumCoeffs]) {
  // First transform columns
  for (int i = 0; i < 32; ++i) {
    double temp_in[32], temp_out[32];
    for (int j = 0; j < 32; ++j) temp_in[j] = input[j * 32 + i];
    reference_32x32_dct_1d(temp_in, temp_out);
    for (int j = 0; j < 32; ++j) output[j * 32 + i] = temp_out[j];
  }
  // Then transform rows
  for (int i = 0; i < 32; ++i) {
    double temp_in[32], temp_out[32];
    for (int j = 0; j < 32; ++j) temp_in[j] = output[j + i * 32];
    reference_32x32_dct_1d(temp_in, temp_out);
    // Scale by some magic number
    for (int j = 0; j < 32; ++j) output[j + i * 32] = temp_out[j] / 4;
  }
}

typedef void (*FwdTxfmFunc)(const int16_t *in, tran_low_t *out, int stride);
typedef void (*InvTxfmFunc)(const tran_low_t *in, uint8_t *out, int stride);

typedef ::testing::tuple<FwdTxfmFunc, InvTxfmFunc, int, aom_bit_depth_t>
    Trans32x32Param;

class Trans32x32Test : public ::testing::TestWithParam<Trans32x32Param> {
 public:
  virtual ~Trans32x32Test() {}
  virtual void SetUp() {
    fwd_txfm_ = GET_PARAM(0);
    inv_txfm_ = GET_PARAM(1);
    version_ = GET_PARAM(2);  // 0: high precision forward transform
                              // 1: low precision version for rd loop
    bit_depth_ = GET_PARAM(3);
    mask_ = (1 << bit_depth_) - 1;
  }

  virtual void TearDown() { libaom_test::ClearSystemState(); }

 protected:
  int version_;
  aom_bit_depth_t bit_depth_;
  int mask_;
  FwdTxfmFunc fwd_txfm_;
  InvTxfmFunc inv_txfm_;
};

TEST_P(Trans32x32Test, AccuracyCheck) {
  ACMRandom rnd(ACMRandom::DeterministicSeed());
  uint32_t max_error = 0;
  int64_t total_error = 0;
  const int count_test_block = 10000;
  DECLARE_ALIGNED(16, int16_t, test_input_block[kNumCoeffs]);
  DECLARE_ALIGNED(16, tran_low_t, test_temp_block[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint8_t, dst[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint8_t, src[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint16_t, dst16[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint16_t, src16[kNumCoeffs]);

  for (int i = 0; i < count_test_block; ++i) {
    // Initialize a test block with input range [-mask_, mask_].
    for (int j = 0; j < kNumCoeffs; ++j) {
      if (bit_depth_ == AOM_BITS_8) {
        src[j] = rnd.Rand8();
        dst[j] = rnd.Rand8();
        test_input_block[j] = src[j] - dst[j];
      } else {
        src16[j] = rnd.Rand16() & mask_;
        dst16[j] = rnd.Rand16() & mask_;
        test_input_block[j] = src16[j] - dst16[j];
      }
    }

    ASM_REGISTER_STATE_CHECK(fwd_txfm_(test_input_block, test_temp_block, 32));
    if (bit_depth_ == AOM_BITS_8) {
      ASM_REGISTER_STATE_CHECK(inv_txfm_(test_temp_block, dst, 32));
    } else {
      ASM_REGISTER_STATE_CHECK(
          inv_txfm_(test_temp_block, CONVERT_TO_BYTEPTR(dst16), 32));
    }

    for (int j = 0; j < kNumCoeffs; ++j) {
      const int32_t diff =
          bit_depth_ == AOM_BITS_8 ? dst[j] - src[j] : dst16[j] - src16[j];
      const uint32_t error = diff * diff;
      if (max_error < error) max_error = error;
      total_error += error;
    }
  }

  if (version_ == 1) {
    max_error /= 2;
    total_error /= 45;
  }

  EXPECT_GE(1u << 2 * (bit_depth_ - 8), max_error)
      << "Error: 32x32 FDCT/IDCT has an individual round-trip error > 1";

  EXPECT_GE(count_test_block << 2 * (bit_depth_ - 8), total_error)
      << "Error: 32x32 FDCT/IDCT has average round-trip error > 1 per block";
}

TEST_P(Trans32x32Test, InverseAccuracy) {
  ACMRandom rnd(ACMRandom::DeterministicSeed());
  const int count_test_block = 1000;
  DECLARE_ALIGNED(16, int16_t, in[kNumCoeffs]);
  DECLARE_ALIGNED(16, tran_low_t, coeff[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint8_t, dst[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint8_t, src[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint16_t, dst16[kNumCoeffs]);
  DECLARE_ALIGNED(16, uint16_t, src16[kNumCoeffs]);

  for (int i = 0; i < count_test_block; ++i) {
    double out_r[kNumCoeffs];

    // Initialize a test block with input range [-255, 255]
    for (int j = 0; j < kNumCoeffs; ++j) {
      if (bit_depth_ == AOM_BITS_8) {
        src[j] = rnd.Rand8();
        dst[j] = rnd.Rand8();
        in[j] = src[j] - dst[j];
      } else {
        src16[j] = rnd.Rand16() & mask_;
        dst16[j] = rnd.Rand16() & mask_;
        in[j] = src16[j] - dst16[j];
      }
    }

    reference_32x32_dct_2d(in, out_r);
    for (int j = 0; j < kNumCoeffs; ++j)
      coeff[j] = static_cast<tran_low_t>(round(out_r[j]));
    if (bit_depth_ == AOM_BITS_8) {
      ASM_REGISTER_STATE_CHECK(inv_txfm_(coeff, dst, 32));
    } else {
      ASM_REGISTER_STATE_CHECK(inv_txfm_(coeff, CONVERT_TO_BYTEPTR(dst16), 32));
    }
    for (int j = 0; j < kNumCoeffs; ++j) {
      const int diff =
          bit_depth_ == AOM_BITS_8 ? dst[j] - src[j] : dst16[j] - src16[j];
      const int error = diff * diff;
      EXPECT_GE(1, error) << "Error: 32x32 IDCT has error " << error
                          << " at index " << j;
    }
  }
}

class PartialTrans32x32Test
    : public ::testing::TestWithParam<
          ::testing::tuple<FwdTxfmFunc, aom_bit_depth_t> > {
 public:
  virtual ~PartialTrans32x32Test() {}
  virtual void SetUp() {
    fwd_txfm_ = GET_PARAM(0);
    bit_depth_ = GET_PARAM(1);
  }

  virtual void TearDown() { libaom_test::ClearSystemState(); }

 protected:
  aom_bit_depth_t bit_depth_;
  FwdTxfmFunc fwd_txfm_;
};

TEST_P(PartialTrans32x32Test, Extremes) {
  const int16_t maxval =
      static_cast<int16_t>(clip_pixel_highbd(1 << 30, bit_depth_));
  const int minval = -maxval;
  DECLARE_ALIGNED(16, int16_t, input[kNumCoeffs]);
  DECLARE_ALIGNED(16, tran_low_t, output[kNumCoeffs]);

  for (int i = 0; i < kNumCoeffs; ++i) input[i] = maxval;
  output[0] = 0;
  ASM_REGISTER_STATE_CHECK(fwd_txfm_(input, output, 32));
  EXPECT_EQ((maxval * kNumCoeffs) >> 3, output[0]);

  for (int i = 0; i < kNumCoeffs; ++i) input[i] = minval;
  output[0] = 0;
  ASM_REGISTER_STATE_CHECK(fwd_txfm_(input, output, 32));
  EXPECT_EQ((minval * kNumCoeffs) >> 3, output[0]);
}

TEST_P(PartialTrans32x32Test, Random) {
  const int16_t maxval =
      static_cast<int16_t>(clip_pixel_highbd(1 << 30, bit_depth_));
  DECLARE_ALIGNED(16, int16_t, input[kNumCoeffs]);
  DECLARE_ALIGNED(16, tran_low_t, output[kNumCoeffs]);
  ACMRandom rnd(ACMRandom::DeterministicSeed());

  int sum = 0;
  for (int i = 0; i < kNumCoeffs; ++i) {
    const int val = (i & 1) ? -rnd(maxval + 1) : rnd(maxval + 1);
    input[i] = val;
    sum += val;
  }
  output[0] = 0;
  ASM_REGISTER_STATE_CHECK(fwd_txfm_(input, output, 32));
  EXPECT_EQ(sum >> 3, output[0]);
}

}  // namespace