src/rewriter/user_segment_history_rewriter.h

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#ifndef MOZC_REWRITER_USER_SEGMENT_HISTORY_REWRITER_H_
#define MOZC_REWRITER_USER_SEGMENT_HISTORY_REWRITER_H_

#include <string>
#include <vector>

#include "rewriter/rewriter_interface.h"
#include "converter/segments.h"

namespace mozc {
class ConversionRequest;
class POSMatcher;
class PosGroup;

namespace storage {
class LRUStorage;
}  // namespace storage

class UserSegmentHistoryRewriter : public RewriterInterface {
 public:
  struct ScoreType {
    uint32 last_access_time;
    uint32 score;
    const Segment::Candidate *candidate;
  };

  UserSegmentHistoryRewriter(const POSMatcher *pos_matcher,
                             const PosGroup *pos_group);
  virtual ~UserSegmentHistoryRewriter();

  virtual bool Rewrite(const ConversionRequest &request,
                       Segments *segments) const;

  virtual void Finish(const ConversionRequest &request, Segments *segments);

  virtual bool Reload();

  virtual void Clear();

 private:
  bool IsAvailable(const Segments &segments) const;
  bool GetScore(const Segments &segments,
                size_t segment_index,
                int candidate_index,
                uint32 *score,
                uint32 *last_access_time) const;
  bool Replaceable(const Segment::Candidate &lhs,
                   const Segment::Candidate &rhs) const;
  void RememberFirstCandidate(const Segments &segments,
                              size_t segment_index);
  void RememberNumberPreference(const Segment &segment);
  bool RewriteNumber(Segment *segment) const;
  bool ShouldRewrite(const Segment &segment,
                     size_t *max_candidates_size) const;
  void InsertTriggerKey(const Segment &segment);
  bool IsPunctuation(const Segment &seg,
                     const Segment::Candidate &candidate) const;
  bool GetFeatureLN(const Segments &segments,
                    size_t i,
                    const string &base_key,
                    const string &base_value,
                    string *value) const;
  bool GetFeatureRN(const Segments &segments,
                    size_t i,
                    const string &base_key,
                    const string &base_value,
                    string *value) const;
  bool SortCandidates(const vector<ScoreType> &sorted_scores,
                      Segment *segment) const;


  scoped_ptr<mozc::storage::LRUStorage> storage_;
  const POSMatcher *pos_matcher_;
  const PosGroup *pos_group_;
};

}  // namespace mozc

#endif  // MOZC_REWRITER_USER_SEGMENT_HISTORY_REWRITER_H_