/*

 * Copyright (c) 2018, 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 <assert.h>

#include <stdbool.h>

#include "config/av1_rtcd.h"

#include "av1/encoder/block.h"

#include "av1/encoder/hash.h"

#include "av1/encoder/hash_motion.h"

#define kSrcBits 16

#define kBlockSizeBits 3

#define kMaxAddr (1 << (kSrcBits + kBlockSizeBits))

// TODO(youzhou@microsoft.com): is higher than 8 bits screen content supported?

// If yes, fix this function

static void get_pixels_in_1D_char_array_by_block_2x2(const uint8_t *y_src,

                                                     int stride,

                                                     uint8_t *p_pixels_in1D) {

  const uint8_t *p_pel = y_src;

  int index = 0;

  for (int i = 0; i < 2; i++) {

    for (int j = 0; j < 2; j++) {

      p_pixels_in1D[index++] = p_pel[j];

    }

    p_pel += stride;

  }

}

static void get_pixels_in_1D_short_array_by_block_2x2(const uint16_t *y_src,

                                                      int stride,

                                                      uint16_t *p_pixels_in1D) {

  const uint16_t *p_pel = y_src;

  int index = 0;

  for (int i = 0; i < 2; i++) {

    for (int j = 0; j < 2; j++) {

      p_pixels_in1D[index++] = p_pel[j];

    }

    p_pel += stride;

  }

}

static int is_block_2x2_row_same_value(const uint8_t *p) {

  if (p[0] != p[1] || p[2] != p[3]) {

    return 0;

  }

  return 1;

}

static int is_block16_2x2_row_same_value(const uint16_t *p) {

  if (p[0] != p[1] || p[2] != p[3]) {

    return 0;

  }

  return 1;

}

static int is_block_2x2_col_same_value(const uint8_t *p) {

  if ((p[0] != p[2]) || (p[1] != p[3])) {

    return 0;

  }

  return 1;

}

static int is_block16_2x2_col_same_value(const uint16_t *p) {

  if ((p[0] != p[2]) || (p[1] != p[3])) {

    return 0;

  }

  return 1;

}

// the hash value (hash_value1 consists two parts, the first 3 bits relate to

// the block size and the remaining 16 bits are the crc values. This fuction

// is used to get the first 3 bits.

static int hash_block_size_to_index(int block_size) {

  switch (block_size) {

    case 4: return 0;

    case 8: return 1;

    case 16: return 2;

    case 32: return 3;

    case 64: return 4;

    case 128: return 5;

    default: return -1;

  }

}

void av1_hash_table_init(IntraBCHashInfo *intrabc_hash_info) {

  if (!intrabc_hash_info->g_crc_initialized) {

    av1_crc_calculator_init(&intrabc_hash_info->crc_calculator1, 24, 0x5D6DCB);

    av1_crc_calculator_init(&intrabc_hash_info->crc_calculator2, 24, 0x864CFB);

    intrabc_hash_info->g_crc_initialized = 1;

  }

  intrabc_hash_info->intrabc_hash_table.p_lookup_table = NULL;

}

static void clear_all(hash_table *p_hash_table) {

  if (p_hash_table->p_lookup_table == NULL) {

    return;

  }

  for (int i = 0; i < kMaxAddr; i++) {

    if (p_hash_table->p_lookup_table[i] != NULL) {

      aom_vector_destroy(p_hash_table->p_lookup_table[i]);

      aom_free(p_hash_table->p_lookup_table[i]);

      p_hash_table->p_lookup_table[i] = NULL;

    }

  }

}

void av1_hash_table_destroy(hash_table *p_hash_table) {

  clear_all(p_hash_table);

  aom_free(p_hash_table->p_lookup_table);

  p_hash_table->p_lookup_table = NULL;

}

bool av1_hash_table_create(hash_table *p_hash_table) {

  if (p_hash_table->p_lookup_table != NULL) {

    clear_all(p_hash_table);

    return true;

  }

  p_hash_table->p_lookup_table =

      (Vector **)aom_calloc(kMaxAddr, sizeof(p_hash_table->p_lookup_table[0]));

  if (!p_hash_table->p_lookup_table) return false;

  return true;

}

static bool hash_table_add_to_table(hash_table *p_hash_table,

                                    uint32_t hash_value,

                                    block_hash *curr_block_hash) {

  if (p_hash_table->p_lookup_table[hash_value] == NULL) {

    p_hash_table->p_lookup_table[hash_value] =

        aom_malloc(sizeof(p_hash_table->p_lookup_table[0][0]));

    if (p_hash_table->p_lookup_table[hash_value] == NULL) {

      return false;

    }

    if (aom_vector_setup(p_hash_table->p_lookup_table[hash_value], 10,

                         sizeof(curr_block_hash[0])) == VECTOR_ERROR)

      return false;

    if (aom_vector_push_back(p_hash_table->p_lookup_table[hash_value],

                             curr_block_hash) == VECTOR_ERROR)

      return false;

  } else {

    if (aom_vector_push_back(p_hash_table->p_lookup_table[hash_value],

                             curr_block_hash) == VECTOR_ERROR)

      return false;

  }

  return true;

}

int32_t av1_hash_table_count(const hash_table *p_hash_table,

                             uint32_t hash_value) {

  if (p_hash_table->p_lookup_table[hash_value] == NULL) {

    return 0;

  } else {

    return (int32_t)(p_hash_table->p_lookup_table[hash_value]->size);

  }

}

Iterator av1_hash_get_first_iterator(hash_table *p_hash_table,

                                     uint32_t hash_value) {

  assert(av1_hash_table_count(p_hash_table, hash_value) > 0);

  return aom_vector_begin(p_hash_table->p_lookup_table[hash_value]);

}

void av1_generate_block_2x2_hash_value(IntraBCHashInfo *intrabc_hash_info,

                                       const YV12_BUFFER_CONFIG *picture,

                                       uint32_t *pic_block_hash[2],

                                       int8_t *pic_block_same_info[3]) {

  const int width = 2;

  const int height = 2;

  const int x_end = picture->y_crop_width - width + 1;

  const int y_end = picture->y_crop_height - height + 1;

  CRC_CALCULATOR *calc_1 = &intrabc_hash_info->crc_calculator1;

  CRC_CALCULATOR *calc_2 = &intrabc_hash_info->crc_calculator2;

  const int length = width * 2;

  if (picture->flags & YV12_FLAG_HIGHBITDEPTH) {

    uint16_t p[4];

    int pos = 0;

    for (int y_pos = 0; y_pos < y_end; y_pos++) {

      for (int x_pos = 0; x_pos < x_end; x_pos++) {

        get_pixels_in_1D_short_array_by_block_2x2(

            CONVERT_TO_SHORTPTR(picture->y_buffer) + y_pos * picture->y_stride +

                x_pos,

            picture->y_stride, p);

        pic_block_same_info[0][pos] = is_block16_2x2_row_same_value(p);

        pic_block_same_info[1][pos] = is_block16_2x2_col_same_value(p);

        pic_block_hash[0][pos] =

            av1_get_crc_value(calc_1, (uint8_t *)p, length * sizeof(p[0]));

        pic_block_hash[1][pos] =

            av1_get_crc_value(calc_2, (uint8_t *)p, length * sizeof(p[0]));

        pos++;

      }

      pos += width - 1;

    }

  } else {

    uint8_t p[4];

    int pos = 0;

    for (int y_pos = 0; y_pos < y_end; y_pos++) {

      for (int x_pos = 0; x_pos < x_end; x_pos++) {

        get_pixels_in_1D_char_array_by_block_2x2(

            picture->y_buffer + y_pos * picture->y_stride + x_pos,

            picture->y_stride, p);

        pic_block_same_info[0][pos] = is_block_2x2_row_same_value(p);

        pic_block_same_info[1][pos] = is_block_2x2_col_same_value(p);

        pic_block_hash[0][pos] =

            av1_get_crc_value(calc_1, p, length * sizeof(p[0]));

        pic_block_hash[1][pos] =

            av1_get_crc_value(calc_2, p, length * sizeof(p[0]));

        pos++;

      }

      pos += width - 1;

    }

  }

}

void av1_generate_block_hash_value(IntraBCHashInfo *intrabc_hash_info,

                                   const YV12_BUFFER_CONFIG *picture,

                                   int block_size,

                                   uint32_t *src_pic_block_hash[2],

                                   uint32_t *dst_pic_block_hash[2],

                                   int8_t *src_pic_block_same_info[3],

                                   int8_t *dst_pic_block_same_info[3]) {

  CRC_CALCULATOR *calc_1 = &intrabc_hash_info->crc_calculator1;

  CRC_CALCULATOR *calc_2 = &intrabc_hash_info->crc_calculator2;

  const int pic_width = picture->y_crop_width;

  const int x_end = picture->y_crop_width - block_size + 1;

  const int y_end = picture->y_crop_height - block_size + 1;

  const int src_size = block_size >> 1;

  const int quad_size = block_size >> 2;

  uint32_t p[4];

  const int length = sizeof(p);

  int pos = 0;

  for (int y_pos = 0; y_pos < y_end; y_pos++) {

    for (int x_pos = 0; x_pos < x_end; x_pos++) {

      p[0] = src_pic_block_hash[0][pos];

      p[1] = src_pic_block_hash[0][pos + src_size];

      p[2] = src_pic_block_hash[0][pos + src_size * pic_width];

      p[3] = src_pic_block_hash[0][pos + src_size * pic_width + src_size];

      dst_pic_block_hash[0][pos] =

          av1_get_crc_value(calc_1, (uint8_t *)p, length);

      p[0] = src_pic_block_hash[1][pos];

      p[1] = src_pic_block_hash[1][pos + src_size];

      p[2] = src_pic_block_hash[1][pos + src_size * pic_width];

      p[3] = src_pic_block_hash[1][pos + src_size * pic_width + src_size];

      dst_pic_block_hash[1][pos] =

          av1_get_crc_value(calc_2, (uint8_t *)p, length);

      dst_pic_block_same_info[0][pos] =

          src_pic_block_same_info[0][pos] &&

          src_pic_block_same_info[0][pos + quad_size] &&

          src_pic_block_same_info[0][pos + src_size] &&

          src_pic_block_same_info[0][pos + src_size * pic_width] &&

          src_pic_block_same_info[0][pos + src_size * pic_width + quad_size] &&

          src_pic_block_same_info[0][pos + src_size * pic_width + src_size];

      dst_pic_block_same_info[1][pos] =

          src_pic_block_same_info[1][pos] &&

          src_pic_block_same_info[1][pos + src_size] &&

          src_pic_block_same_info[1][pos + quad_size * pic_width] &&

          src_pic_block_same_info[1][pos + quad_size * pic_width + src_size] &&

          src_pic_block_same_info[1][pos + src_size * pic_width] &&

          src_pic_block_same_info[1][pos + src_size * pic_width + src_size];

      pos++;

    }

    pos += block_size - 1;

  }

  if (block_size >= 4) {

    const int size_minus_1 = block_size - 1;

    pos = 0;

    for (int y_pos = 0; y_pos < y_end; y_pos++) {

      for (int x_pos = 0; x_pos < x_end; x_pos++) {

        dst_pic_block_same_info[2][pos] =

            (!dst_pic_block_same_info[0][pos] &&

             !dst_pic_block_same_info[1][pos]) ||

            (((x_pos & size_minus_1) == 0) && ((y_pos & size_minus_1) == 0));

        pos++;

      }

      pos += block_size - 1;

    }

  }

}

bool av1_add_to_hash_map_by_row_with_precal_data(hash_table *p_hash_table,

                                                 uint32_t *pic_hash[2],

                                                 int8_t *pic_is_same,

                                                 int pic_width, int pic_height,

                                                 int block_size) {

  const int x_end = pic_width - block_size + 1;

  const int y_end = pic_height - block_size + 1;

  const int8_t *src_is_added = pic_is_same;

  const uint32_t *src_hash[2] = { pic_hash[0], pic_hash[1] };

  int add_value = hash_block_size_to_index(block_size);

  assert(add_value >= 0);

  add_value <<= kSrcBits;

  const int crc_mask = (1 << kSrcBits) - 1;

  for (int x_pos = 0; x_pos < x_end; x_pos++) {

    for (int y_pos = 0; y_pos < y_end; y_pos++) {

      const int pos = y_pos * pic_width + x_pos;

      // valid data

      if (src_is_added[pos]) {

        block_hash curr_block_hash;

        curr_block_hash.x = x_pos;

        curr_block_hash.y = y_pos;

        const uint32_t hash_value1 = (src_hash[0][pos] & crc_mask) + add_value;

        curr_block_hash.hash_value2 = src_hash[1][pos];

        if (!hash_table_add_to_table(p_hash_table, hash_value1,

                                     &curr_block_hash)) {

          return false;

        }

      }

    }

  }

  return true;

}

int av1_hash_is_horizontal_perfect(const YV12_BUFFER_CONFIG *picture,

                                   int block_size, int x_start, int y_start) {

  const int stride = picture->y_stride;

  const uint8_t *p = picture->y_buffer + y_start * stride + x_start;

  if (picture->flags & YV12_FLAG_HIGHBITDEPTH) {

    const uint16_t *p16 = CONVERT_TO_SHORTPTR(p);

    for (int i = 0; i < block_size; i++) {

      for (int j = 1; j < block_size; j++) {

        if (p16[j] != p16[0]) {

          return 0;

        }

      }

      p16 += stride;

    }

  } else {

    for (int i = 0; i < block_size; i++) {

      for (int j = 1; j < block_size; j++) {

        if (p[j] != p[0]) {

          return 0;

        }

      }

      p += stride;

    }

  }

  return 1;

}

int av1_hash_is_vertical_perfect(const YV12_BUFFER_CONFIG *picture,

                                 int block_size, int x_start, int y_start) {

  const int stride = picture->y_stride;

  const uint8_t *p = picture->y_buffer + y_start * stride + x_start;

  if (picture->flags & YV12_FLAG_HIGHBITDEPTH) {

    const uint16_t *p16 = CONVERT_TO_SHORTPTR(p);

    for (int i = 0; i < block_size; i++) {

      for (int j = 1; j < block_size; j++) {

        if (p16[j * stride + i] != p16[i]) {

          return 0;

        }

      }

    }

  } else {

    for (int i = 0; i < block_size; i++) {

      for (int j = 1; j < block_size; j++) {

        if (p[j * stride + i] != p[i]) {

          return 0;

        }

      }

    }

  }

  return 1;

}

void av1_get_block_hash_value(IntraBCHashInfo *intrabc_hash_info,

                              const uint8_t *y_src, int stride, int block_size,

                              uint32_t *hash_value1, uint32_t *hash_value2,

                              int use_highbitdepth) {

  int add_value = hash_block_size_to_index(block_size);

  assert(add_value >= 0);

  add_value <<= kSrcBits;

  const int crc_mask = (1 << kSrcBits) - 1;

  CRC_CALCULATOR *calc_1 = &intrabc_hash_info->crc_calculator1;

  CRC_CALCULATOR *calc_2 = &intrabc_hash_info->crc_calculator2;

  uint32_t **buf_1 = intrabc_hash_info->hash_value_buffer[0];

  uint32_t **buf_2 = intrabc_hash_info->hash_value_buffer[1];

  // 2x2 subblock hash values in current CU

  int sub_block_in_width = (block_size >> 1);

  if (use_highbitdepth) {

    uint16_t pixel_to_hash[4];

    uint16_t *y16_src = CONVERT_TO_SHORTPTR(y_src);

    for (int y_pos = 0; y_pos < block_size; y_pos += 2) {

      for (int x_pos = 0; x_pos < block_size; x_pos += 2) {

        int pos = (y_pos >> 1) * sub_block_in_width + (x_pos >> 1);

        get_pixels_in_1D_short_array_by_block_2x2(

            y16_src + y_pos * stride + x_pos, stride, pixel_to_hash);

        assert(pos < AOM_BUFFER_SIZE_FOR_BLOCK_HASH);

        buf_1[0][pos] = av1_get_crc_value(calc_1, (uint8_t *)pixel_to_hash,

                                          sizeof(pixel_to_hash));

        buf_2[0][pos] = av1_get_crc_value(calc_2, (uint8_t *)pixel_to_hash,

                                          sizeof(pixel_to_hash));

      }

    }

  } else {

    uint8_t pixel_to_hash[4];

    for (int y_pos = 0; y_pos < block_size; y_pos += 2) {

      for (int x_pos = 0; x_pos < block_size; x_pos += 2) {

        int pos = (y_pos >> 1) * sub_block_in_width + (x_pos >> 1);

        get_pixels_in_1D_char_array_by_block_2x2(y_src + y_pos * stride + x_pos,

                                                 stride, pixel_to_hash);

        assert(pos < AOM_BUFFER_SIZE_FOR_BLOCK_HASH);

        buf_1[0][pos] =

            av1_get_crc_value(calc_1, pixel_to_hash, sizeof(pixel_to_hash));

        buf_2[0][pos] =

            av1_get_crc_value(calc_2, pixel_to_hash, sizeof(pixel_to_hash));

      }

    }

  }

  int src_sub_block_in_width = sub_block_in_width;

  sub_block_in_width >>= 1;

  int src_idx = 1;

  int dst_idx = 0;

  // 4x4 subblock hash values to current block hash values

  uint32_t to_hash[4];

  for (int sub_width = 4; sub_width <= block_size; sub_width *= 2) {

    src_idx = 1 - src_idx;

    dst_idx = 1 - dst_idx;

    int dst_pos = 0;

    for (int y_pos = 0; y_pos < sub_block_in_width; y_pos++) {

      for (int x_pos = 0; x_pos < sub_block_in_width; x_pos++) {

        int srcPos = (y_pos << 1) * src_sub_block_in_width + (x_pos << 1);

        assert(srcPos + 1 < AOM_BUFFER_SIZE_FOR_BLOCK_HASH);

        assert(srcPos + src_sub_block_in_width + 1 <

               AOM_BUFFER_SIZE_FOR_BLOCK_HASH);

        assert(dst_pos < AOM_BUFFER_SIZE_FOR_BLOCK_HASH);

        to_hash[0] = buf_1[src_idx][srcPos];

        to_hash[1] = buf_1[src_idx][srcPos + 1];

        to_hash[2] = buf_1[src_idx][srcPos + src_sub_block_in_width];

        to_hash[3] = buf_1[src_idx][srcPos + src_sub_block_in_width + 1];

        buf_1[dst_idx][dst_pos] =

            av1_get_crc_value(calc_1, (uint8_t *)to_hash, sizeof(to_hash));

        to_hash[0] = buf_2[src_idx][srcPos];

        to_hash[1] = buf_2[src_idx][srcPos + 1];

        to_hash[2] = buf_2[src_idx][srcPos + src_sub_block_in_width];

        to_hash[3] = buf_2[src_idx][srcPos + src_sub_block_in_width + 1];

        buf_2[dst_idx][dst_pos] =

            av1_get_crc_value(calc_2, (uint8_t *)to_hash, sizeof(to_hash));

        dst_pos++;

      }

    }

    src_sub_block_in_width = sub_block_in_width;

    sub_block_in_width >>= 1;

  }

  *hash_value1 = (buf_1[dst_idx][0] & crc_mask) + add_value;

  *hash_value2 = buf_2[dst_idx][0];

}