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#include "converter/segmenter_base.h"

#include "base/base.h"
#include "base/bitarray.h"
#include "converter/boundary_struct.h"
#include "converter/node.h"

namespace mozc {

SegmenterBase::SegmenterBase(
    size_t l_size, size_t r_size, const uint16 *l_table, const uint16 *r_table,
    size_t bitarray_size, const char *bitarray_data,
    const BoundaryData *boundary_data)
    : l_size_(l_size), r_size_(r_size), l_table_(l_table), r_table_(r_table),
      bitarray_size_(bitarray_size), bitarray_data_(bitarray_data),
      boundary_data_(boundary_data) {
  DCHECK(l_table);
  DCHECK(r_table);
  DCHECK(bitarray_data);
  DCHECK(boundary_data);
}

SegmenterBase::~SegmenterBase() {}

bool SegmenterBase::IsBoundary(const Node *lnode, const Node *rnode,
                               bool is_single_segment) const {
  DCHECK(lnode);
  DCHECK(rnode);
  if (lnode->node_type == Node::BOS_NODE ||
      rnode->node_type == Node::EOS_NODE) {
    return true;
  }

  // return always false in prediction mode.
  // This implies that converter always returns single-segment-result
  // in prediction mode.
  if (is_single_segment) {
    return false;
  }

  const bool is_boundary = IsBoundary(lnode->rid, rnode->lid);

  // Concatenate particle and content word into one segment,
  // if lnode locates at the beginning of user input.
  // This hack is for handling ambiguous bunsetsu segmentation.
  // e.g. "かみ|にかく" => "紙|に書く" or "紙二角".
  // If we segment "に書く" into two segments, "二角" is never be shown.
  // There exits some implicit assumpution that user expects that his/her input
  // becomes one bunsetu. So, it would be better to keep "二角" even after "紙".
  if (is_boundary && (lnode->attributes & Node::STARTS_WITH_PARTICLE)) {
    return false;
  }

  return is_boundary;
}

bool SegmenterBase::IsBoundary(uint16 rid, uint16 lid) const {
  return BitArray::GetValue(reinterpret_cast<const char*>(bitarray_data_),
                            l_table_[rid] + l_size_ * r_table_[lid]);
}

int32 SegmenterBase::GetPrefixPenalty(uint16 lid) const {
  return boundary_data_[lid].prefix_penalty;
}

int32 SegmenterBase::GetSuffixPenalty(uint16 rid) const {
  return boundary_data_[rid].suffix_penalty;
}
}  // namespace mozc