/*
 * 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.
 */

#ifndef AOM_DSP_DAALABOOLWRITER_H_
#define AOM_DSP_DAALABOOLWRITER_H_

#include <stdio.h>

#include "aom_dsp/entenc.h"
#include "aom_dsp/prob.h"
#if CONFIG_BITSTREAM_DEBUG
#include "aom_util/debug_util.h"
#endif  // CONFIG_BITSTREAM_DEBUG

#ifdef __cplusplus
extern "C" {
#endif

struct daala_writer {
  unsigned int pos;
  uint8_t *buffer;
  od_ec_enc ec;
};

typedef struct daala_writer daala_writer;

void aom_daala_start_encode(daala_writer *w, uint8_t *buffer);
void aom_daala_stop_encode(daala_writer *w);

static INLINE void aom_daala_write(daala_writer *w, int bit, int prob) {
  int p = ((prob << 15) + (256 - prob)) >> 8;
#if CONFIG_BITSTREAM_DEBUG
  aom_cdf_prob cdf[2] = { (aom_cdf_prob)p, 32767 };
  /*int queue_r = 0;
  int frame_idx_r = 0;
  int queue_w = bitstream_queue_get_write();
  int frame_idx_w = bitstream_queue_get_frame_write();
  if (frame_idx_w == frame_idx_r && queue_w == queue_r) {
    fprintf(stderr, "\n *** bitstream queue at frame_idx_w %d queue_w %d\n",
    frame_idx_w, queue_w);
  }*/
  bitstream_queue_push(bit, cdf, 2);
#endif

  od_ec_encode_bool_q15(&w->ec, bit, p);
}

static INLINE void aom_daala_write_bit(daala_writer *w, int bit) {
  od_ec_enc_bits(&w->ec, bit, 1);
}

static INLINE void daala_write_symbol(daala_writer *w, int symb,
                                      const aom_cdf_prob *cdf, int nsymbs) {
#if CONFIG_BITSTREAM_DEBUG
  /*int queue_r = 0;
  int frame_idx_r = 0;
  int queue_w = bitstream_queue_get_write();
  int frame_idx_w = bitstream_queue_get_frame_write();
  if (frame_idx_w == frame_idx_r && queue_w == queue_r) {
    fprintf(stderr, "\n *** bitstream queue at frame_idx_w %d queue_w %d\n",
    frame_idx_w, queue_w);
  }*/
  bitstream_queue_push(symb, cdf, nsymbs);
#endif

  od_ec_encode_cdf_q15(&w->ec, symb, cdf, nsymbs);
}

static INLINE void daala_write_tree_bits(daala_writer *w,
                                         const aom_tree_index *tree,
                                         const aom_prob *probs, int bits,
                                         int len, aom_tree_index i) {
  aom_tree_index root;
  root = i;
  do {
    aom_cdf_prob cdf[16];
    aom_tree_index index[16];
    int path[16];
    int dist[16];
    int nsymbs;
    int symb;
    int j;
    /* Compute the CDF of the binary tree using the given probabilities. */
    nsymbs = tree_to_cdf(tree, probs, root, cdf, index, path, dist);
    /* Find the symbol to code. */
    symb = -1;
    for (j = 0; j < nsymbs; j++) {
      /* If this symbol codes a leaf node,  */
      if (index[j] <= 0) {
        if (len == dist[j] && path[j] == bits) {
          symb = j;
          break;
        }
      } else {
        if (len > dist[j] && path[j] == bits >> (len - dist[j])) {
          symb = j;
          break;
        }
      }
    }
    OD_ASSERT(symb != -1);
    daala_write_symbol(w, symb, cdf, nsymbs);
    bits &= (1 << (len - dist[symb])) - 1;
    len -= dist[symb];
  } while (len);
}

#ifdef __cplusplus
}  // extern "C"
#endif

#endif