/*
 *  Copyright (c) 2016 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 <stdlib.h>
#include "vpx/vpx_integer.h"

const int16_t vpx_rv[] = {8, 5, 2, 2, 8, 12, 4, 9, 8, 3, 0, 3, 9, 0, 0, 0, 8, 3,
    14, 4, 10, 1, 11, 14, 1, 14, 9, 6, 12, 11, 8, 6, 10, 0, 0, 8, 9, 0, 3, 14,
    8, 11, 13, 4, 2, 9, 0, 3, 9, 6, 1, 2, 3, 14, 13, 1, 8, 2, 9, 7, 3, 3, 1, 13,
    13, 6, 6, 5, 2, 7, 11, 9, 11, 8, 7, 3, 2, 0, 13, 13, 14, 4, 12, 5, 12, 10,
    8, 10, 13, 10, 4, 14, 4, 10, 0, 8, 11, 1, 13, 7, 7, 14, 6, 14, 13, 2, 13, 5,
    4, 4, 0, 10, 0, 5, 13, 2, 12, 7, 11, 13, 8, 0, 4, 10, 7, 2, 7, 2, 2, 5, 3,
    4, 7, 3, 3, 14, 14, 5, 9, 13, 3, 14, 3, 6, 3, 0, 11, 8, 13, 1, 13, 1, 12, 0,
    10, 9, 7, 6, 2, 8, 5, 2, 13, 7, 1, 13, 14, 7, 6, 7, 9, 6, 10, 11, 7, 8, 7,
    5, 14, 8, 4, 4, 0, 8, 7, 10, 0, 8, 14, 11, 3, 12, 5, 7, 14, 3, 14, 5, 2, 6,
    11, 12, 12, 8, 0, 11, 13, 1, 2, 0, 5, 10, 14, 7, 8, 0, 4, 11, 0, 8, 0, 3,
    10, 5, 8, 0, 11, 6, 7, 8, 10, 7, 13, 9, 2, 5, 1, 5, 10, 2, 4, 3, 5, 6, 10,
    8, 9, 4, 11, 14, 0, 10, 0, 5, 13, 2, 12, 7, 11, 13, 8, 0, 4, 10, 7, 2, 7, 2,
    2, 5, 3, 4, 7, 3, 3, 14, 14, 5, 9, 13, 3, 14, 3, 6, 3, 0, 11, 8, 13, 1, 13,
    1, 12, 0, 10, 9, 7, 6, 2, 8, 5, 2, 13, 7, 1, 13, 14, 7, 6, 7, 9, 6, 10, 11,
    7, 8, 7, 5, 14, 8, 4, 4, 0, 8, 7, 10, 0, 8, 14, 11, 3, 12, 5, 7, 14, 3, 14,
    5, 2, 6, 11, 12, 12, 8, 0, 11, 13, 1, 2, 0, 5, 10, 14, 7, 8, 0, 4, 11, 0, 8,
    0, 3, 10, 5, 8, 0, 11, 6, 7, 8, 10, 7, 13, 9, 2, 5, 1, 5, 10, 2, 4, 3, 5, 6,
    10, 8, 9, 4, 11, 14, 3, 8, 3, 7, 8, 5, 11, 4, 12, 3, 11, 9, 14, 8, 14, 13,
    4, 3, 1, 2, 14, 6, 5, 4, 4, 11, 4, 6, 2, 1, 5, 8, 8, 12, 13, 5, 14, 10, 12,
    13, 0, 9, 5, 5, 11, 10, 13, 9, 10, 13, };

void vpx_post_proc_down_and_across_mb_row_c(unsigned char *src_ptr,
                                            unsigned char *dst_ptr,
                                            int src_pixels_per_line,
                                            int dst_pixels_per_line, int cols,
                                            unsigned char *f, int size) {
  unsigned char *p_src, *p_dst;
  int row;
  int col;
  unsigned char v;
  unsigned char d[4];

  for (row = 0; row < size; row++) {
    /* post_proc_down for one row */
    p_src = src_ptr;
    p_dst = dst_ptr;

    for (col = 0; col < cols; col++) {
      unsigned char p_above2 = p_src[col - 2 * src_pixels_per_line];
      unsigned char p_above1 = p_src[col - src_pixels_per_line];
      unsigned char p_below1 = p_src[col + src_pixels_per_line];
      unsigned char p_below2 = p_src[col + 2 * src_pixels_per_line];

      v = p_src[col];

      if ((abs(v - p_above2) < f[col]) && (abs(v - p_above1) < f[col])
          && (abs(v - p_below1) < f[col]) && (abs(v - p_below2) < f[col])) {
        unsigned char k1, k2, k3;
        k1 = (p_above2 + p_above1 + 1) >> 1;
        k2 = (p_below2 + p_below1 + 1) >> 1;
        k3 = (k1 + k2 + 1) >> 1;
        v = (k3 + v + 1) >> 1;
      }

      p_dst[col] = v;
    }

    /* now post_proc_across */
    p_src = dst_ptr;
    p_dst = dst_ptr;

    p_src[-2] = p_src[-1] = p_src[0];
    p_src[cols] = p_src[cols + 1] = p_src[cols - 1];

    for (col = 0; col < cols; col++) {
      v = p_src[col];

      if ((abs(v - p_src[col - 2]) < f[col])
          && (abs(v - p_src[col - 1]) < f[col])
          && (abs(v - p_src[col + 1]) < f[col])
          && (abs(v - p_src[col + 2]) < f[col])) {
        unsigned char k1, k2, k3;
        k1 = (p_src[col - 2] + p_src[col - 1] + 1) >> 1;
        k2 = (p_src[col + 2] + p_src[col + 1] + 1) >> 1;
        k3 = (k1 + k2 + 1) >> 1;
        v = (k3 + v + 1) >> 1;
      }

      d[col & 3] = v;

      if (col >= 2)
        p_dst[col - 2] = d[(col - 2) & 3];
    }

    /* handle the last two pixels */
    p_dst[col - 2] = d[(col - 2) & 3];
    p_dst[col - 1] = d[(col - 1) & 3];

    /* next row */
    src_ptr += src_pixels_per_line;
    dst_ptr += dst_pixels_per_line;
  }
}

void vpx_mbpost_proc_across_ip_c(unsigned char *src, int pitch, int rows,
                                 int cols, int flimit) {
  int r, c, i;

  unsigned char *s = src;
  unsigned char d[16];

  for (r = 0; r < rows; r++) {
    int sumsq = 0;
    int sum = 0;

    for (i = -8; i < 0; i++)
      s[i] = s[0];

    /* 17 avoids valgrind warning - we buffer values in c in d
     * and only write them when we've read 8 ahead...
     */
    for (i = 0; i < 17; i++)
      s[i + cols] = s[cols - 1];

    for (i = -8; i <= 6; i++) {
      sumsq += s[i] * s[i];
      sum += s[i];
      d[i + 8] = 0;
    }

    for (c = 0; c < cols + 8; c++) {
      int x = s[c + 7] - s[c - 8];
      int y = s[c + 7] + s[c - 8];

      sum += x;
      sumsq += x * y;

      d[c & 15] = s[c];

      if (sumsq * 15 - sum * sum < flimit) {
        d[c & 15] = (8 + sum + s[c]) >> 4;
      }

      s[c - 8] = d[(c - 8) & 15];
    }

    s += pitch;
  }
}

void vpx_mbpost_proc_down_c(unsigned char *dst, int pitch, int rows, int cols,
                            int flimit) {
  int r, c, i;
  const int16_t *rv3 = &vpx_rv[63 & rand()];

  for (c = 0; c < cols; c++) {
    unsigned char *s = &dst[c];
    int sumsq = 0;
    int sum = 0;
    unsigned char d[16];
    const int16_t *rv2 = rv3 + ((c * 17) & 127);

    for (i = -8; i < 0; i++)
      s[i * pitch] = s[0];

    /* 17 avoids valgrind warning - we buffer values in c in d
     * and only write them when we've read 8 ahead...
     */
    for (i = 0; i < 17; i++)
      s[(i + rows) * pitch] = s[(rows - 1) * pitch];

    for (i = -8; i <= 6; i++) {
      sumsq += s[i * pitch] * s[i * pitch];
      sum += s[i * pitch];
    }

    for (r = 0; r < rows + 8; r++) {
      sumsq += s[7 * pitch] * s[7 * pitch] - s[-8 * pitch] * s[-8 * pitch];
      sum += s[7 * pitch] - s[-8 * pitch];
      d[r & 15] = s[0];

      if (sumsq * 15 - sum * sum < flimit) {
        d[r & 15] = (rv2[r & 127] + sum + s[0]) >> 4;
      }
      if (r >= 8)
        s[-8 * pitch] = d[(r - 8) & 15];
      s += pitch;
    }
  }
}

#if CONFIG_POSTPROC
static void vpx_de_mblock(YV12_BUFFER_CONFIG *post,
    int q) {
  vpx_mbpost_proc_across_ip(post->y_buffer, post->y_stride, post->y_height,
      post->y_width, q2mbl(q));
  vpx_mbpost_proc_down(post->y_buffer, post->y_stride, post->y_height,
      post->y_width, q2mbl(q));
}

#endif