/*
 * 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 "./av1_rtcd.h"
#include "aom_dsp/x86/inv_txfm_sse2.h"
#include "aom_dsp/x86/synonyms.h"
#include "aom_dsp/x86/txfm_common_sse2.h"
#include "aom_ports/mem.h"
#include "av1/common/enums.h"

static INLINE void fliplr_4x4(__m128i *in /*in[2]*/) {
  in[0] = _mm_shufflelo_epi16(in[0], 0x1b);
  in[0] = _mm_shufflehi_epi16(in[0], 0x1b);
  in[1] = _mm_shufflelo_epi16(in[1], 0x1b);
  in[1] = _mm_shufflehi_epi16(in[1], 0x1b);
}

static INLINE void fliplr_8x8(__m128i *in /*in[8]*/) {
  in[0] = mm_reverse_epi16(in[0]);
  in[1] = mm_reverse_epi16(in[1]);
  in[2] = mm_reverse_epi16(in[2]);
  in[3] = mm_reverse_epi16(in[3]);

  in[4] = mm_reverse_epi16(in[4]);
  in[5] = mm_reverse_epi16(in[5]);
  in[6] = mm_reverse_epi16(in[6]);
  in[7] = mm_reverse_epi16(in[7]);
}

static INLINE void fliplr_16x8(__m128i *in /*in[16]*/) {
  fliplr_8x8(&in[0]);
  fliplr_8x8(&in[8]);
}

#define FLIPLR_16x16(in0, in1) \
  do {                         \
    __m128i *tmp;              \
    fliplr_16x8(in0);          \
    fliplr_16x8(in1);          \
    tmp = (in0);               \
    (in0) = (in1);             \
    (in1) = tmp;               \
  } while (0)

#define FLIPUD_PTR(dest, stride, size)       \
  do {                                       \
    (dest) = (dest) + ((size)-1) * (stride); \
    (stride) = -(stride);                    \
  } while (0)

void av1_iht4x4_16_add_sse2(const tran_low_t *input, uint8_t *dest, int stride,
                            const TxfmParam *txfm_param) {
  __m128i in[2];
  const __m128i zero = _mm_setzero_si128();
  const __m128i eight = _mm_set1_epi16(8);
  const TX_TYPE tx_type = txfm_param->tx_type;

  in[0] = load_input_data(input);
  in[1] = load_input_data(input + 8);

  switch (tx_type) {
    case DCT_DCT:
      aom_idct4_sse2(in);
      aom_idct4_sse2(in);
      break;
    case ADST_DCT:
      aom_idct4_sse2(in);
      aom_iadst4_sse2(in);
      break;
    case DCT_ADST:
      aom_iadst4_sse2(in);
      aom_idct4_sse2(in);
      break;
    case ADST_ADST:
      aom_iadst4_sse2(in);
      aom_iadst4_sse2(in);
      break;
    case FLIPADST_DCT:
      aom_idct4_sse2(in);
      aom_iadst4_sse2(in);
      FLIPUD_PTR(dest, stride, 4);
      break;
    case DCT_FLIPADST:
      aom_iadst4_sse2(in);
      aom_idct4_sse2(in);
      fliplr_4x4(in);
      break;
    case FLIPADST_FLIPADST:
      aom_iadst4_sse2(in);
      aom_iadst4_sse2(in);
      FLIPUD_PTR(dest, stride, 4);
      fliplr_4x4(in);
      break;
    case ADST_FLIPADST:
      aom_iadst4_sse2(in);
      aom_iadst4_sse2(in);
      fliplr_4x4(in);
      break;
    case FLIPADST_ADST:
      aom_iadst4_sse2(in);
      aom_iadst4_sse2(in);
      FLIPUD_PTR(dest, stride, 4);
      break;
    default: assert(0); break;
  }

  // Final round and shift
  in[0] = _mm_add_epi16(in[0], eight);
  in[1] = _mm_add_epi16(in[1], eight);

  in[0] = _mm_srai_epi16(in[0], 4);
  in[1] = _mm_srai_epi16(in[1], 4);

  // Reconstruction and Store
  {
    __m128i d0 = _mm_cvtsi32_si128(*(const int *)(dest + stride * 0));
    __m128i d1 = _mm_cvtsi32_si128(*(const int *)(dest + stride * 1));
    __m128i d2 = _mm_cvtsi32_si128(*(const int *)(dest + stride * 2));
    __m128i d3 = _mm_cvtsi32_si128(*(const int *)(dest + stride * 3));
    d0 = _mm_unpacklo_epi32(d0, d1);
    d2 = _mm_unpacklo_epi32(d2, d3);
    d0 = _mm_unpacklo_epi8(d0, zero);
    d2 = _mm_unpacklo_epi8(d2, zero);
    d0 = _mm_add_epi16(d0, in[0]);
    d2 = _mm_add_epi16(d2, in[1]);
    d0 = _mm_packus_epi16(d0, d2);
    // store result[0]
    *(int *)dest = _mm_cvtsi128_si32(d0);
    // store result[1]
    d0 = _mm_srli_si128(d0, 4);
    *(int *)(dest + stride) = _mm_cvtsi128_si32(d0);
    // store result[2]
    d0 = _mm_srli_si128(d0, 4);
    *(int *)(dest + stride * 2) = _mm_cvtsi128_si32(d0);
    // store result[3]
    d0 = _mm_srli_si128(d0, 4);
    *(int *)(dest + stride * 3) = _mm_cvtsi128_si32(d0);
  }
}