cppjieba/src/PosTagger.hpp

#ifndef CPPJIEBA_POS_TAGGING_H
#define CPPJIEBA_POS_TAGGING_H

#include "MixSegment.hpp"
#include "Limonp/StringUtil.hpp"
#include "DictTrie.hpp"

namespace CppJieba {
using namespace Limonp;

static const char* const POS_M = "m";
static const char* const POS_ENG = "eng";
static const char* const POS_X = "x";

class PosTagger {
 public:
  PosTagger(const string& dictPath,
    const string& hmmFilePath,
    const string& userDictPath = "")
    : segment_(dictPath, hmmFilePath, userDictPath) {
  }
  PosTagger(const DictTrie* dictTrie, const HMMModel* model) 
    : segment_(dictTrie, model) {
  }
  ~PosTagger() {
  }

  bool tag(const string& src, vector<pair<string, string> >& res) const {
    vector<string> cutRes;
    if (!segment_.cut(src, cutRes)) {
      LogError("mixSegment_ cut failed");
      return false;
    }

    const DictUnit *tmp = NULL;
    Unicode unico;
    const DictTrie * dict = segment_.getDictTrie();
    assert(dict != NULL);
    for (vector<string>::iterator itr = cutRes.begin(); itr != cutRes.end(); ++itr) {
      if (!TransCode::decode(*itr, unico)) {
        LogError("decode failed.");
        return false;
      }
      tmp = dict->find(unico.begin(), unico.end());
      if(tmp == NULL || tmp->tag.empty()) {
        res.push_back(make_pair(*itr, specialRule_(unico)));
      } else {
        res.push_back(make_pair(*itr, tmp->tag));
      }
    }
    return !res.empty();
  }
 private:
  const char* specialRule_(const Unicode& unicode) const {
    size_t m = 0;
    size_t eng = 0;
    for(size_t i = 0; i < unicode.size() && eng < unicode.size() / 2; i++) {
      if(unicode[i] < 0x80) {
        eng ++;
        if('0' <= unicode[i] && unicode[i] <= '9') {
          m++;
        }
      }
    }
    // ascii char is not found
    if(eng == 0) {
      return POS_X;
    }
    // all the ascii is number char
    if(m == eng) {
      return POS_M;
    }
    // the ascii chars contain english letter
    return POS_ENG;
  }
 private:
  MixSegment segment_;
}; // class PosTagger

} // namespace CppJieba

#endif