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

#include "config/aom_scale_rtcd.h"

#include "aom/aom_integer.h"
#include "av1/common/av1_common_int.h"
#include "av1/common/cdef.h"
#include "av1/common/cdef_block.h"
#include "av1/common/reconinter.h"

enum { TOP, LEFT, BOTTOM, RIGHT, BOUNDARIES } UENUM1BYTE(BOUNDARY);

/*!\brief Parameters related to CDEF Block */
typedef struct {
  uint16_t *src;
  uint16_t *top_linebuf[MAX_MB_PLANE];
  uint16_t *bot_linebuf[MAX_MB_PLANE];
  uint8_t *dst;
  cdef_list dlist[MI_SIZE_64X64 * MI_SIZE_64X64];

  int xdec;
  int ydec;
  int mi_wide_l2;
  int mi_high_l2;
  int frame_boundary[BOUNDARIES];

  int damping;
  int coeff_shift;
  int level;
  int sec_strength;
  int cdef_count;
  int is_zero_level;
  int dir[CDEF_NBLOCKS][CDEF_NBLOCKS];
  int var[CDEF_NBLOCKS][CDEF_NBLOCKS];

  int dst_stride;
  int coffset;
  int roffset;
} CdefBlockInfo;

static int is_8x8_block_skip(MB_MODE_INFO **grid, int mi_row, int mi_col,
                             int mi_stride) {
  MB_MODE_INFO **mbmi = grid + mi_row * mi_stride + mi_col;
  for (int r = 0; r < mi_size_high[BLOCK_8X8]; ++r, mbmi += mi_stride) {
    for (int c = 0; c < mi_size_wide[BLOCK_8X8]; ++c) {
      if (!mbmi[c]->skip_txfm) return 0;
    }
  }

  return 1;
}

int av1_cdef_compute_sb_list(const CommonModeInfoParams *const mi_params,
                             int mi_row, int mi_col, cdef_list *dlist,
                             BLOCK_SIZE bs) {
  MB_MODE_INFO **grid = mi_params->mi_grid_base;
  int maxc = mi_params->mi_cols - mi_col;
  int maxr = mi_params->mi_rows - mi_row;

  if (bs == BLOCK_128X128 || bs == BLOCK_128X64)
    maxc = AOMMIN(maxc, MI_SIZE_128X128);
  else
    maxc = AOMMIN(maxc, MI_SIZE_64X64);
  if (bs == BLOCK_128X128 || bs == BLOCK_64X128)
    maxr = AOMMIN(maxr, MI_SIZE_128X128);
  else
    maxr = AOMMIN(maxr, MI_SIZE_64X64);

  const int r_step = 2;  // mi_size_high[BLOCK_8X8]
  const int c_step = 2;  // mi_size_wide[BLOCK_8X8]
  const int r_shift = 1;
  const int c_shift = 1;
  int count = 0;
  for (int r = 0; r < maxr; r += r_step) {
    for (int c = 0; c < maxc; c += c_step) {
      if (!is_8x8_block_skip(grid, mi_row + r, mi_col + c,
                             mi_params->mi_stride)) {
        dlist[count].by = r >> r_shift;
        dlist[count].bx = c >> c_shift;
        count++;
      }
    }
  }
  return count;
}

void cdef_copy_rect8_8bit_to_16bit_c(uint16_t *dst, int dstride,
                                     const uint8_t *src, int sstride, int v,
                                     int h) {
  for (int i = 0; i < v; i++) {
    for (int j = 0; j < h; j++) {
      dst[i * dstride + j] = src[i * sstride + j];
    }
  }
}

void cdef_copy_rect8_16bit_to_16bit_c(uint16_t *dst, int dstride,
                                      const uint16_t *src, int sstride, int v,
                                      int h) {
  for (int i = 0; i < v; i++) {
    for (int j = 0; j < h; j++) {
      dst[i * dstride + j] = src[i * sstride + j];
    }
  }
}

static void copy_sb8_16(AV1_COMMON *cm, uint16_t *dst, int dstride,
                        const uint8_t *src, int src_voffset, int src_hoffset,
                        int sstride, int vsize, int hsize) {
  if (cm->seq_params.use_highbitdepth) {
    const uint16_t *base =
        &CONVERT_TO_SHORTPTR(src)[src_voffset * sstride + src_hoffset];
    cdef_copy_rect8_16bit_to_16bit(dst, dstride, base, sstride, vsize, hsize);
  } else {
    const uint8_t *base = &src[src_voffset * sstride + src_hoffset];
    cdef_copy_rect8_8bit_to_16bit(dst, dstride, base, sstride, vsize, hsize);
  }
}

static INLINE void fill_rect(uint16_t *dst, int dstride, int v, int h,
                             uint16_t x) {
  for (int i = 0; i < v; i++) {
    for (int j = 0; j < h; j++) {
      dst[i * dstride + j] = x;
    }
  }
}

static INLINE void copy_rect(uint16_t *dst, int dstride, const uint16_t *src,
                             int sstride, int v, int h) {
  for (int i = 0; i < v; i++) {
    for (int j = 0; j < h; j++) {
      dst[i * dstride + j] = src[i * sstride + j];
    }
  }
}

// Prepares intermediate input buffer for CDEF.
// Inputs:
//   cm: Pointer to common structure.
//   fb_info: Pointer to the CDEF block-level parameter structure.
//   colbuf: Left column buffer for CDEF.
//   cdef_left: Left block is filtered or not.
//   fbc, fbr: col and row index of a block.
//   plane: plane index Y/CB/CR.
// Returns:
//   Nothing will be returned.
static void cdef_prepare_fb(AV1_COMMON *cm, CdefBlockInfo *fb_info,
                            uint16_t **const colbuf, const int *cdef_left,
                            int fbc, int fbr, uint8_t plane) {
  const CommonModeInfoParams *const mi_params = &cm->mi_params;
  uint16_t *src = fb_info->src;
  const int luma_stride = mi_params->mi_cols << MI_SIZE_LOG2;
  const int nvfb = (mi_params->mi_rows + MI_SIZE_64X64 - 1) / MI_SIZE_64X64;
  const int nhfb = (mi_params->mi_cols + MI_SIZE_64X64 - 1) / MI_SIZE_64X64;
  int cstart = 0;
  if (!*cdef_left) cstart = -CDEF_HBORDER;
  int rend, cend;
  int nhb = AOMMIN(MI_SIZE_64X64, mi_params->mi_cols - MI_SIZE_64X64 * fbc);
  int nvb = AOMMIN(MI_SIZE_64X64, mi_params->mi_rows - MI_SIZE_64X64 * fbr);
  int hsize = nhb << fb_info->mi_wide_l2;
  int vsize = nvb << fb_info->mi_high_l2;
  const uint16_t *top_linebuf = fb_info->top_linebuf[plane];
  const uint16_t *bot_linebuf = fb_info->bot_linebuf[plane];
  const int bot_offset = (vsize + CDEF_VBORDER) * CDEF_BSTRIDE;
  const int stride =
      luma_stride >> (plane == AOM_PLANE_Y ? 0 : cm->seq_params.subsampling_x);

  if (fbc == nhfb - 1)
    cend = hsize;
  else
    cend = hsize + CDEF_HBORDER;

  if (fbr == nvfb - 1)
    rend = vsize;
  else
    rend = vsize + CDEF_VBORDER;

  /* Copy in the pixels we need from the current superblock for
  deringing.*/
  copy_sb8_16(cm, &src[CDEF_VBORDER * CDEF_BSTRIDE + CDEF_HBORDER + cstart],
              CDEF_BSTRIDE, fb_info->dst, fb_info->roffset,
              fb_info->coffset + cstart, fb_info->dst_stride, vsize,
              cend - cstart);

  /* Copy in the pixels we need for the current superblock from bottom buffer.*/
  if (fbr < nvfb - 1) {
    copy_rect(&src[bot_offset + CDEF_HBORDER], CDEF_BSTRIDE,
              &bot_linebuf[fb_info->coffset], stride, CDEF_VBORDER, hsize);
  } else {
    fill_rect(&src[bot_offset + CDEF_HBORDER], CDEF_BSTRIDE, CDEF_VBORDER,
              hsize, CDEF_VERY_LARGE);
  }
  if (fbr < nvfb - 1 && fbc > 0) {
    copy_rect(&src[bot_offset], CDEF_BSTRIDE,
              &bot_linebuf[fb_info->coffset - CDEF_HBORDER], stride,
              CDEF_VBORDER, CDEF_HBORDER);
  } else {
    fill_rect(&src[bot_offset], CDEF_BSTRIDE, CDEF_VBORDER, CDEF_HBORDER,
              CDEF_VERY_LARGE);
  }
  if (fbr < nvfb - 1 && fbc < nhfb - 1) {
    copy_rect(&src[bot_offset + hsize + CDEF_HBORDER], CDEF_BSTRIDE,
              &bot_linebuf[fb_info->coffset + hsize], stride, CDEF_VBORDER,
              CDEF_HBORDER);
  } else {
    fill_rect(&src[bot_offset + hsize + CDEF_HBORDER], CDEF_BSTRIDE,
              CDEF_VBORDER, CDEF_HBORDER, CDEF_VERY_LARGE);
  }

  /* Copy in the pixels we need from the current superblock from top buffer.*/
  if (fbr > 0) {
    copy_rect(&src[CDEF_HBORDER], CDEF_BSTRIDE, &top_linebuf[fb_info->coffset],
              stride, CDEF_VBORDER, hsize);
  } else {
    fill_rect(&src[CDEF_HBORDER], CDEF_BSTRIDE, CDEF_VBORDER, hsize,
              CDEF_VERY_LARGE);
  }
  if (fbr > 0 && fbc > 0) {
    copy_rect(src, CDEF_BSTRIDE, &top_linebuf[fb_info->coffset - CDEF_HBORDER],
              stride, CDEF_VBORDER, CDEF_HBORDER);
  } else {
    fill_rect(src, CDEF_BSTRIDE, CDEF_VBORDER, CDEF_HBORDER, CDEF_VERY_LARGE);
  }
  if (fbr > 0 && fbc < nhfb - 1) {
    copy_rect(&src[hsize + CDEF_HBORDER], CDEF_BSTRIDE,
              &top_linebuf[fb_info->coffset + hsize], stride, CDEF_VBORDER,
              CDEF_HBORDER);
  } else {
    fill_rect(&src[hsize + CDEF_HBORDER], CDEF_BSTRIDE, CDEF_VBORDER,
              CDEF_HBORDER, CDEF_VERY_LARGE);
  }
  if (*cdef_left) {
    /* If we deringed the superblock on the left then we need to copy in
    saved pixels. */
    copy_rect(src, CDEF_BSTRIDE, colbuf[plane], CDEF_HBORDER,
              rend + CDEF_VBORDER, CDEF_HBORDER);
  }
  /* Saving pixels in case we need to dering the superblock on the
  right. */
  copy_rect(colbuf[plane], CDEF_HBORDER, src + hsize, CDEF_BSTRIDE,
            rend + CDEF_VBORDER, CDEF_HBORDER);

  if (fb_info->frame_boundary[LEFT]) {
    fill_rect(src, CDEF_BSTRIDE, vsize + 2 * CDEF_VBORDER, CDEF_HBORDER,
              CDEF_VERY_LARGE);
  }
  if (fb_info->frame_boundary[RIGHT]) {
    fill_rect(&src[hsize + CDEF_HBORDER], CDEF_BSTRIDE,
              vsize + 2 * CDEF_VBORDER, CDEF_HBORDER, CDEF_VERY_LARGE);
  }
}

static INLINE void cdef_filter_fb(CdefBlockInfo *fb_info, uint8_t plane,
                                  uint8_t use_highbitdepth) {
  int offset = fb_info->dst_stride * fb_info->roffset + fb_info->coffset;
  if (use_highbitdepth) {
    av1_cdef_filter_fb(
        NULL, CONVERT_TO_SHORTPTR(fb_info->dst + offset), fb_info->dst_stride,
        &fb_info->src[CDEF_VBORDER * CDEF_BSTRIDE + CDEF_HBORDER],
        fb_info->xdec, fb_info->ydec, fb_info->dir, NULL, fb_info->var, plane,
        fb_info->dlist, fb_info->cdef_count, fb_info->level,
        fb_info->sec_strength, fb_info->damping, fb_info->coeff_shift);
  } else {
    av1_cdef_filter_fb(
        fb_info->dst + offset, NULL, fb_info->dst_stride,
        &fb_info->src[CDEF_VBORDER * CDEF_BSTRIDE + CDEF_HBORDER],
        fb_info->xdec, fb_info->ydec, fb_info->dir, NULL, fb_info->var, plane,
        fb_info->dlist, fb_info->cdef_count, fb_info->level,
        fb_info->sec_strength, fb_info->damping, fb_info->coeff_shift);
  }
}

// Initializes block-level parameters for CDEF.
static INLINE void cdef_init_fb_col(MACROBLOCKD *xd,
                                    const CdefInfo *const cdef_info,
                                    CdefBlockInfo *fb_info,
                                    const int mbmi_cdef_strength, int fbc,
                                    int fbr, uint8_t plane) {
  if (plane == AOM_PLANE_Y) {
    fb_info->level =
        cdef_info->cdef_strengths[mbmi_cdef_strength] / CDEF_SEC_STRENGTHS;
    fb_info->sec_strength =
        cdef_info->cdef_strengths[mbmi_cdef_strength] % CDEF_SEC_STRENGTHS;
    fb_info->sec_strength += fb_info->sec_strength == 3;
    int uv_level =
        cdef_info->cdef_uv_strengths[mbmi_cdef_strength] / CDEF_SEC_STRENGTHS;
    int uv_sec_strength =
        cdef_info->cdef_uv_strengths[mbmi_cdef_strength] % CDEF_SEC_STRENGTHS;
    uv_sec_strength += uv_sec_strength == 3;
    fb_info->is_zero_level = (fb_info->level == 0) &&
                             (fb_info->sec_strength == 0) && (uv_level == 0) &&
                             (uv_sec_strength == 0);
  } else {
    fb_info->level =
        cdef_info->cdef_uv_strengths[mbmi_cdef_strength] / CDEF_SEC_STRENGTHS;
    fb_info->sec_strength =
        cdef_info->cdef_uv_strengths[mbmi_cdef_strength] % CDEF_SEC_STRENGTHS;
    fb_info->sec_strength += fb_info->sec_strength == 3;
  }
  fb_info->dst = xd->plane[plane].dst.buf;
  fb_info->dst_stride = xd->plane[plane].dst.stride;

  fb_info->xdec = xd->plane[plane].subsampling_x;
  fb_info->ydec = xd->plane[plane].subsampling_y;
  fb_info->mi_wide_l2 = MI_SIZE_LOG2 - xd->plane[plane].subsampling_x;
  fb_info->mi_high_l2 = MI_SIZE_LOG2 - xd->plane[plane].subsampling_y;
  fb_info->roffset = MI_SIZE_64X64 * fbr << fb_info->mi_high_l2;
  fb_info->coffset = MI_SIZE_64X64 * fbc << fb_info->mi_wide_l2;
}

static void cdef_fb_col(AV1_COMMON *cm, MACROBLOCKD *xd, CdefBlockInfo *fb_info,
                        uint16_t **const colbuf, int *cdef_left, int fbc,
                        int fbr) {
  const CommonModeInfoParams *const mi_params = &cm->mi_params;
  const int mbmi_cdef_strength =
      mi_params
          ->mi_grid_base[MI_SIZE_64X64 * fbr * mi_params->mi_stride +
                         MI_SIZE_64X64 * fbc]
          ->cdef_strength;
  const int num_planes = av1_num_planes(cm);

  if (mi_params->mi_grid_base[MI_SIZE_64X64 * fbr * mi_params->mi_stride +
                              MI_SIZE_64X64 * fbc] == NULL ||
      mbmi_cdef_strength == -1) {
    *cdef_left = 0;
    return;
  }
  for (uint8_t plane = 0; plane < num_planes; plane++) {
    cdef_init_fb_col(xd, &cm->cdef_info, fb_info, mbmi_cdef_strength, fbc, fbr,
                     plane);
    if (fb_info->is_zero_level ||
        (fb_info->cdef_count = av1_cdef_compute_sb_list(
             mi_params, fbr * MI_SIZE_64X64, fbc * MI_SIZE_64X64,
             fb_info->dlist, BLOCK_64X64)) == 0) {
      *cdef_left = 0;
      return;
    }
    cdef_prepare_fb(cm, fb_info, colbuf, cdef_left, fbc, fbr, plane);
    cdef_filter_fb(fb_info, plane, cm->seq_params.use_highbitdepth);
  }
  *cdef_left = 1;
}

static INLINE void cdef_init_fb_row(AV1_COMMON *cm, MACROBLOCKD *const xd,
                                    CdefBlockInfo *fb_info,
                                    uint16_t **const linebuf,
                                    uint16_t *const src, int fbr) {
  const int num_planes = av1_num_planes(cm);
  const int nvfb = (cm->mi_params.mi_rows + MI_SIZE_64X64 - 1) / MI_SIZE_64X64;
  const int luma_stride = cm->mi_params.mi_cols << MI_SIZE_LOG2;
  const bool ping_pong = fbr & 1;
  // for the current filter block, it's top left corner mi structure (mi_tl)
  // is first accessed to check whether the top and left boundaries are
  // frame boundaries. Then bottom-left and top-right mi structures are
  // accessed to check whether the bottom and right boundaries
  // (respectively) are frame boundaries.
  //
  // Note that we can't just check the bottom-right mi structure - eg. if
  // we're at the right-hand edge of the frame but not the bottom, then
  // the bottom-right mi is NULL but the bottom-left is not.
  fb_info->frame_boundary[TOP] = (MI_SIZE_64X64 * fbr == 0) ? 1 : 0;
  if (fbr != nvfb - 1)
    fb_info->frame_boundary[BOTTOM] =
        (MI_SIZE_64X64 * (fbr + 1) == cm->mi_params.mi_rows) ? 1 : 0;
  else
    fb_info->frame_boundary[BOTTOM] = 1;

  fb_info->src = src;
  fb_info->damping = cm->cdef_info.cdef_damping;
  fb_info->coeff_shift = AOMMAX(cm->seq_params.bit_depth - 8, 0);
  av1_zero(fb_info->dir);
  av1_zero(fb_info->var);

  for (uint8_t plane = 0; plane < num_planes; plane++) {
    const int mi_high_l2 = MI_SIZE_LOG2 - xd->plane[plane].subsampling_y;
    const int offset = MI_SIZE_64X64 * (fbr + 1) << mi_high_l2;
    const int stride = luma_stride >> xd->plane[plane].subsampling_x;
    // here ping-pong buffers are maintained for top linebuf
    // to avoid linebuf over-write by consecutive row.
    uint16_t *const top_linebuf =
        &linebuf[plane][ping_pong * CDEF_VBORDER * stride];
    fb_info->bot_linebuf[plane] = &linebuf[plane][(CDEF_VBORDER << 1) * stride];

    if (fbr != nvfb - 1)  // top line buffer copy
      copy_sb8_16(cm, top_linebuf, stride, xd->plane[plane].dst.buf,
                  offset - CDEF_VBORDER, 0, xd->plane[plane].dst.stride,
                  CDEF_VBORDER, stride);
    fb_info->top_linebuf[plane] =
        &linebuf[plane][(!ping_pong) * CDEF_VBORDER * stride];

    if (fbr != nvfb - 1)  // bottom line buffer copy
      copy_sb8_16(cm, fb_info->bot_linebuf[plane], stride,
                  xd->plane[plane].dst.buf, offset, 0,
                  xd->plane[plane].dst.stride, CDEF_VBORDER, stride);
  }
}

static void cdef_fb_row(AV1_COMMON *cm, MACROBLOCKD *xd,
                        uint16_t **const linebuf, uint16_t **const colbuf,
                        uint16_t *const src, int fbr) {
  CdefBlockInfo fb_info;
  int cdef_left = 1;
  const int nhfb = (cm->mi_params.mi_cols + MI_SIZE_64X64 - 1) / MI_SIZE_64X64;

  cdef_init_fb_row(cm, xd, &fb_info, linebuf, src, fbr);
  for (int fbc = 0; fbc < nhfb; fbc++) {
    fb_info.frame_boundary[LEFT] = (MI_SIZE_64X64 * fbc == 0) ? 1 : 0;
    if (fbc != nhfb - 1)
      fb_info.frame_boundary[RIGHT] =
          (MI_SIZE_64X64 * (fbc + 1) == cm->mi_params.mi_cols) ? 1 : 0;
    else
      fb_info.frame_boundary[RIGHT] = 1;
    cdef_fb_col(cm, xd, &fb_info, colbuf, &cdef_left, fbc, fbr);
  }
}

// Perform CDEF on input frame.
// Inputs:
//   frame: Pointer to input frame buffer.
//   cm: Pointer to common structure.
//   xd: Pointer to common current coding block structure.
// Returns:
//   Nothing will be returned.
void av1_cdef_frame(YV12_BUFFER_CONFIG *frame, AV1_COMMON *cm,
                    MACROBLOCKD *xd) {
  const int num_planes = av1_num_planes(cm);
  const int nvfb = (cm->mi_params.mi_rows + MI_SIZE_64X64 - 1) / MI_SIZE_64X64;

  av1_setup_dst_planes(xd->plane, cm->seq_params.sb_size, frame, 0, 0, 0,
                       num_planes);

  for (int fbr = 0; fbr < nvfb; fbr++)
    cdef_fb_row(cm, xd, cm->cdef_info.linebuf, cm->cdef_info.colbuf,
                cm->cdef_info.srcbuf, fbr);
}