/*

 *  Copyright (c) 2010 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 <math.h>

#include "vp9/common/vp9_common.h"

#include "vp9/common/vp9_entropymode.h"

#include "vp9/encoder/vp9_cost.h"

#include "vp9/encoder/vp9_encodemv.h"

#include "vpx_dsp/vpx_dsp_common.h"

static struct vp9_token mv_joint_encodings[MV_JOINTS];

static struct vp9_token mv_class_encodings[MV_CLASSES];

static struct vp9_token mv_fp_encodings[MV_FP_SIZE];

void vp9_entropy_mv_init(void) {

  vp9_tokens_from_tree(mv_joint_encodings, vp9_mv_joint_tree);

  vp9_tokens_from_tree(mv_class_encodings, vp9_mv_class_tree);

  vp9_tokens_from_tree(mv_fp_encodings, vp9_mv_fp_tree);

}

static void encode_mv_component(vpx_writer *w, int comp,

                                const nmv_component *mvcomp, int usehp) {

  int offset;

  const int sign = comp < 0;

  const int mag = sign ? -comp : comp;

  const int mv_class = vp9_get_mv_class(mag - 1, &offset);

  const int d = offset >> 3;         // int mv data

  const int fr = (offset >> 1) & 3;  // fractional mv data

  const int hp = offset & 1;         // high precision mv data

  assert(comp != 0);

  // Sign

  vpx_write(w, sign, mvcomp->sign);

  // Class

  vp9_write_token(w, vp9_mv_class_tree, mvcomp->classes,

                  &mv_class_encodings[mv_class]);

  // Integer bits

  if (mv_class == MV_CLASS_0) {

    vpx_write(w, d, mvcomp->class0[0]);

  } else {

    int i;

    const int n = mv_class + CLASS0_BITS - 1;  // number of bits

    for (i = 0; i < n; ++i) vpx_write(w, (d >> i) & 1, mvcomp->bits[i]);

  }

  // Fractional bits

  vp9_write_token(w, vp9_mv_fp_tree,

                  mv_class == MV_CLASS_0 ? mvcomp->class0_fp[d] : mvcomp->fp,

                  &mv_fp_encodings[fr]);

  // High precision bit

  if (usehp)

    vpx_write(w, hp, mv_class == MV_CLASS_0 ? mvcomp->class0_hp : mvcomp->hp);

}

static void build_nmv_component_cost_table(int *mvcost,

                                           const nmv_component *const mvcomp,

                                           int usehp) {

  int sign_cost[2], class_cost[MV_CLASSES], class0_cost[CLASS0_SIZE];

  int bits_cost[MV_OFFSET_BITS][2];

  int class0_fp_cost[CLASS0_SIZE][MV_FP_SIZE], fp_cost[MV_FP_SIZE];

  int class0_hp_cost[2], hp_cost[2];

  int i;

  int c, o;

  sign_cost[0] = vp9_cost_zero(mvcomp->sign);

  sign_cost[1] = vp9_cost_one(mvcomp->sign);

  vp9_cost_tokens(class_cost, mvcomp->classes, vp9_mv_class_tree);

  vp9_cost_tokens(class0_cost, mvcomp->class0, vp9_mv_class0_tree);

  for (i = 0; i < MV_OFFSET_BITS; ++i) {

    bits_cost[i][0] = vp9_cost_zero(mvcomp->bits[i]);

    bits_cost[i][1] = vp9_cost_one(mvcomp->bits[i]);

  }

  for (i = 0; i < CLASS0_SIZE; ++i)

    vp9_cost_tokens(class0_fp_cost[i], mvcomp->class0_fp[i], vp9_mv_fp_tree);

  vp9_cost_tokens(fp_cost, mvcomp->fp, vp9_mv_fp_tree);

  // Always build the hp costs to avoid an uninitialized warning from gcc

  class0_hp_cost[0] = vp9_cost_zero(mvcomp->class0_hp);

  class0_hp_cost[1] = vp9_cost_one(mvcomp->class0_hp);

  hp_cost[0] = vp9_cost_zero(mvcomp->hp);

  hp_cost[1] = vp9_cost_one(mvcomp->hp);

  mvcost[0] = 0;

  // MV_CLASS_0

  for (o = 0; o < (CLASS0_SIZE << 3); ++o) {

    int d, e, f;

    int cost = class_cost[MV_CLASS_0];

    int v = o + 1;

    d = (o >> 3);     /* int mv data */

    f = (o >> 1) & 3; /* fractional pel mv data */

    cost += class0_cost[d];

    cost += class0_fp_cost[d][f];

    if (usehp) {

      e = (o & 1); /* high precision mv data */

      cost += class0_hp_cost[e];

    }

    mvcost[v] = cost + sign_cost[0];

    mvcost[-v] = cost + sign_cost[1];

  }

  for (c = MV_CLASS_1; c < MV_CLASSES; ++c) {

    int d;

    for (d = 0; d < (1 << c); ++d) {

      int f;

      int whole_cost = class_cost[c];

      int b = c + CLASS0_BITS - 1; /* number of bits */

      for (i = 0; i < b; ++i) whole_cost += bits_cost[i][((d >> i) & 1)];

      for (f = 0; f < 4; ++f) {

        int cost = whole_cost + fp_cost[f];

        int v = (CLASS0_SIZE << (c + 2)) + d * 8 + f * 2 /* + e */ + 1;

        if (usehp) {

          mvcost[v] = cost + hp_cost[0] + sign_cost[0];

          mvcost[-v] = cost + hp_cost[0] + sign_cost[1];

          if (v + 1 > MV_MAX) break;

          mvcost[v + 1] = cost + hp_cost[1] + sign_cost[0];

          mvcost[-v - 1] = cost + hp_cost[1] + sign_cost[1];

        } else {

          mvcost[v] = cost + sign_cost[0];

          mvcost[-v] = cost + sign_cost[1];

          if (v + 1 > MV_MAX) break;

          mvcost[v + 1] = cost + sign_cost[0];

          mvcost[-v - 1] = cost + sign_cost[1];

        }

      }

    }

  }

}

static int update_mv(vpx_writer *w, const unsigned int ct[2], vpx_prob *cur_p,

                     vpx_prob upd_p) {

  const vpx_prob new_p = get_binary_prob(ct[0], ct[1]) | 1;

  const int update = cost_branch256(ct, *cur_p) + vp9_cost_zero(upd_p) >

                     cost_branch256(ct, new_p) + vp9_cost_one(upd_p) +

                         (7 << VP9_PROB_COST_SHIFT);

  vpx_write(w, update, upd_p);

  if (update) {

    *cur_p = new_p;

    vpx_write_literal(w, new_p >> 1, 7);

  }

  return update;

}

static void write_mv_update(const vpx_tree_index *tree,

                            vpx_prob probs[/*n - 1*/],

                            const unsigned int counts[/*n - 1*/], int n,

                            vpx_writer *w) {

  int i;

  unsigned int branch_ct[32][2];

  // Assuming max number of probabilities <= 32

  assert(n <= 32);

  vp9_tree_probs_from_distribution(tree, branch_ct, counts);

  for (i = 0; i < n - 1; ++i)

    update_mv(w, branch_ct[i], &probs[i], MV_UPDATE_PROB);

}

void vp9_write_nmv_probs(VP9_COMMON *cm, int usehp, vpx_writer *w,

                         nmv_context_counts *const counts) {

  int i, j;

  nmv_context *const mvc = &cm->fc->nmvc;

  write_mv_update(vp9_mv_joint_tree, mvc->joints, counts->joints, MV_JOINTS, w);

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

    nmv_component *comp = &mvc->comps[i];

    nmv_component_counts *comp_counts = &counts->comps[i];

    update_mv(w, comp_counts->sign, &comp->sign, MV_UPDATE_PROB);

    write_mv_update(vp9_mv_class_tree, comp->classes, comp_counts->classes,

                    MV_CLASSES, w);

    write_mv_update(vp9_mv_class0_tree, comp->class0, comp_counts->class0,

                    CLASS0_SIZE, w);

    for (j = 0; j < MV_OFFSET_BITS; ++j)

      update_mv(w, comp_counts->bits[j], &comp->bits[j], MV_UPDATE_PROB);

  }

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

    for (j = 0; j < CLASS0_SIZE; ++j)

      write_mv_update(vp9_mv_fp_tree, mvc->comps[i].class0_fp[j],

                      counts->comps[i].class0_fp[j], MV_FP_SIZE, w);

    write_mv_update(vp9_mv_fp_tree, mvc->comps[i].fp, counts->comps[i].fp,

                    MV_FP_SIZE, w);

  }

  if (usehp) {

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

      update_mv(w, counts->comps[i].class0_hp, &mvc->comps[i].class0_hp,

                MV_UPDATE_PROB);

      update_mv(w, counts->comps[i].hp, &mvc->comps[i].hp, MV_UPDATE_PROB);

    }

  }

}

void vp9_encode_mv(VP9_COMP *cpi, vpx_writer *w, const MV *mv, const MV *ref,

                   const nmv_context *mvctx, int usehp,

                   unsigned int *const max_mv_magnitude) {

  const MV diff = { mv->row - ref->row, mv->col - ref->col };

  const MV_JOINT_TYPE j = vp9_get_mv_joint(&diff);

  usehp = usehp && use_mv_hp(ref);

  vp9_write_token(w, vp9_mv_joint_tree, mvctx->joints, &mv_joint_encodings[j]);

  if (mv_joint_vertical(j))

    encode_mv_component(w, diff.row, &mvctx->comps[0], usehp);

  if (mv_joint_horizontal(j))

    encode_mv_component(w, diff.col, &mvctx->comps[1], usehp);

  // If auto_mv_step_size is enabled then keep track of the largest

  // motion vector component used.

  if (cpi->sf.mv.auto_mv_step_size) {

    const unsigned int maxv = VPXMAX(abs(mv->row), abs(mv->col)) >> 3;

    *max_mv_magnitude = VPXMAX(maxv, *max_mv_magnitude);

  }

}

void vp9_build_nmv_cost_table(int *mvjoint, int *mvcost[2],

                              const nmv_context *ctx, int usehp) {

  vp9_cost_tokens(mvjoint, ctx->joints, vp9_mv_joint_tree);

  build_nmv_component_cost_table(mvcost[0], &ctx->comps[0], usehp);

  build_nmv_component_cost_table(mvcost[1], &ctx->comps[1], usehp);

}

static void inc_mvs(const MODE_INFO *mi, const MB_MODE_INFO_EXT *mbmi_ext,

                    const int_mv mvs[2], nmv_context_counts *counts) {

  int i;

  for (i = 0; i < 1 + has_second_ref(mi); ++i) {

    const MV *ref = &mbmi_ext->ref_mvs[mi->ref_frame[i]][0].as_mv;

    const MV diff = { mvs[i].as_mv.row - ref->row,

                      mvs[i].as_mv.col - ref->col };

    vp9_inc_mv(&diff, counts);

  }

}

void vp9_update_mv_count(ThreadData *td) {

  const MACROBLOCKD *xd = &td->mb.e_mbd;

  const MODE_INFO *mi = xd->mi[0];

  const MB_MODE_INFO_EXT *mbmi_ext = td->mb.mbmi_ext;

  if (mi->sb_type < BLOCK_8X8) {

    const int num_4x4_w = num_4x4_blocks_wide_lookup[mi->sb_type];

    const int num_4x4_h = num_4x4_blocks_high_lookup[mi->sb_type];

    int idx, idy;

    for (idy = 0; idy < 2; idy += num_4x4_h) {

      for (idx = 0; idx < 2; idx += num_4x4_w) {

        const int i = idy * 2 + idx;

        if (mi->bmi[i].as_mode == NEWMV)

          inc_mvs(mi, mbmi_ext, mi->bmi[i].as_mv, &td->counts->mv);

      }

    }

  } else {

    if (mi->mode == NEWMV) inc_mvs(mi, mbmi_ext, mi->mv, &td->counts->mv);

  }

}