/*
 * 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 <string.h>
#include <math.h>

#include "./aom_scale_rtcd.h"
#include "aom/aom_integer.h"
#include "av1/common/dering.h"
#include "av1/common/onyxc_int.h"
#include "av1/common/reconinter.h"
#include "av1/common/od_dering.h"


int compute_level_from_index(int global_level, int gi) {
  static const int dering_gains[DERING_REFINEMENT_LEVELS] = {0, 11, 16, 22};
  int level;
  if (global_level == 0) return 0;
  level = (global_level*dering_gains[gi] + 8) >> 4;
  return clamp(level, gi, MAX_DERING_LEVEL-1);
}

int sb_all_skip(const AV1_COMMON *const cm, int mi_row, int mi_col) {
  int r, c;
  int maxc, maxr;
  int skip = 1;
  maxc = cm->mi_cols - mi_col;
  maxr = cm->mi_rows - mi_row;
  if (maxr > MI_BLOCK_SIZE) maxr = MI_BLOCK_SIZE;
  if (maxc > MI_BLOCK_SIZE) maxc = MI_BLOCK_SIZE;
  for (r = 0; r < maxr; r++) {
    for (c = 0; c < maxc; c++) {
      skip = skip &&
          cm->mi_grid_visible[(mi_row + r)*cm->mi_stride + mi_col + c]->
          mbmi.skip;
    }
  }
  return skip;
}

void av1_dering_frame(YV12_BUFFER_CONFIG *frame, AV1_COMMON *cm,
                       MACROBLOCKD *xd, int global_level) {
  int r, c;
  int sbr, sbc;
  int nhsb, nvsb;
  od_dering_in *src[3];
  unsigned char *bskip;
  int dir[OD_DERING_NBLOCKS][OD_DERING_NBLOCKS] = {{0}};
  int stride;
  int bsize[3];
  int dec[3];
  int pli;
  int coeff_shift = AOMMAX(cm->bit_depth - 8, 0);
  nvsb = (cm->mi_rows + MI_BLOCK_SIZE - 1)/MI_BLOCK_SIZE;
  nhsb = (cm->mi_cols + MI_BLOCK_SIZE - 1)/MI_BLOCK_SIZE;
  bskip = aom_malloc(sizeof(*bskip)*cm->mi_rows*cm->mi_cols);
  av1_setup_dst_planes(xd->plane, frame, 0, 0);
  for (pli = 0; pli < 3; pli++) {
    dec[pli] = xd->plane[pli].subsampling_x;
    bsize[pli] = 8 >> dec[pli];
  }
  stride = bsize[0]*cm->mi_cols;
  for (pli = 0; pli < 3; pli++) {
    src[pli] = aom_malloc(sizeof(*src)*cm->mi_rows*cm->mi_cols*64);
    for (r = 0; r < bsize[pli]*cm->mi_rows; ++r) {
      for (c = 0; c < bsize[pli]*cm->mi_cols; ++c) {
#if CONFIG_AOM_HIGHBITDEPTH
        if (cm->use_highbitdepth) {
          src[pli][r * stride + c] =
              CONVERT_TO_SHORTPTR(xd->plane[pli].dst.buf)
              [r * xd->plane[pli].dst.stride + c];
        } else {
#endif
          src[pli][r * stride + c] =
              xd->plane[pli].dst.buf[r * xd->plane[pli].dst.stride + c];
#if CONFIG_AOM_HIGHBITDEPTH
        }
#endif
      }
    }
  }
  for (r = 0; r < cm->mi_rows; ++r) {
    for (c = 0; c < cm->mi_cols; ++c) {
      const MB_MODE_INFO *mbmi =
          &cm->mi_grid_visible[r * cm->mi_stride + c]->mbmi;
      bskip[r * cm->mi_cols + c] = mbmi->skip;
    }
  }
  for (sbr = 0; sbr < nvsb; sbr++) {
    for (sbc = 0; sbc < nhsb; sbc++) {
      int level;
      int nhb, nvb;
      nhb = AOMMIN(MI_BLOCK_SIZE, cm->mi_cols - MI_BLOCK_SIZE*sbc);
      nvb = AOMMIN(MI_BLOCK_SIZE, cm->mi_rows - MI_BLOCK_SIZE*sbr);
      for (pli = 0; pli < 3; pli++) {
        int16_t dst[MI_BLOCK_SIZE*MI_BLOCK_SIZE*8*8];
        int threshold;
#if DERING_REFINEMENT
        level = compute_level_from_index(
            global_level,
            cm->mi_grid_visible[MI_BLOCK_SIZE*sbr*cm->mi_stride +
            MI_BLOCK_SIZE*sbc]->mbmi.dering_gain);
#else
        level = global_level;
#endif
        /* FIXME: This is a temporary hack that uses more conservative
           deringing for chroma. */
        if (pli) level = (level*5 + 4) >> 3;
        if (sb_all_skip(cm, sbr*MI_BLOCK_SIZE, sbc*MI_BLOCK_SIZE)) level = 0;
        threshold = level << coeff_shift;
        od_dering(
            &OD_DERING_VTBL_C,
            dst,
            MI_BLOCK_SIZE*bsize[pli],
            &src[pli][sbr*stride*bsize[pli]*MI_BLOCK_SIZE +
            sbc*bsize[pli]*MI_BLOCK_SIZE],
            stride, nhb, nvb, sbc, sbr, nhsb, nvsb, dec[pli], dir, pli,
            &bskip[MI_BLOCK_SIZE*sbr*cm->mi_cols + MI_BLOCK_SIZE*sbc],
            cm->mi_cols, threshold, OD_DERING_NO_CHECK_OVERLAP, coeff_shift);
        for (r = 0; r < bsize[pli]*nvb; ++r) {
          for (c = 0; c < bsize[pli]*nhb; ++c) {
#if CONFIG_AOM_HIGHBITDEPTH
            if (cm->use_highbitdepth) {
              CONVERT_TO_SHORTPTR(xd->plane[pli].dst.buf)
                  [xd->plane[pli].dst.stride*(bsize[pli]*MI_BLOCK_SIZE*sbr + r)
                  + sbc*bsize[pli]*MI_BLOCK_SIZE + c] =
                  dst[r * MI_BLOCK_SIZE * bsize[pli] + c];
            } else {
#endif
              xd->plane[pli].dst.buf[xd->plane[pli].dst.stride*
                  (bsize[pli]*MI_BLOCK_SIZE*sbr + r) +
                  sbc*bsize[pli]*MI_BLOCK_SIZE + c] =
                  dst[r * MI_BLOCK_SIZE * bsize[pli] + c];
#if CONFIG_AOM_HIGHBITDEPTH
            }
#endif
          }
        }
      }
    }
  }
  for (pli = 0; pli < 3; pli++) {
    aom_free(src[pli]);
  }
  aom_free(bskip);
}