/*
 * This file is part of the KDE libraries
 *
 * Copyright (c) 2000-2003 Shiro Kawai <shirok@users.sourceforge.net>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *  3. Neither the name of the authors nor the names of its contributors
 *     may be used to endorse or promote products derived from this
 *     software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
/*
 * original code is here.
 * http://cvs.sourceforge.net/viewcvs.py/gauche/Gauche/ext/charconv/guess.c?view=markup
 */
#ifndef GUESS_JA_H
#define GUESS_JA_H

class guess_arc {
 public:
  unsigned int next;          /* next state */
  double score;               /* score */
};


typedef signed char dfa_table[256];

/* DFA tables declared in guess_ja.cpp */
extern const dfa_table guess_eucj_st[];
extern guess_arc guess_eucj_ar[7];
extern const dfa_table guess_sjis_st[];
extern guess_arc guess_sjis_ar[6];
extern const dfa_table guess_utf8_st[];
extern guess_arc guess_utf8_ar[11];

class guess_dfa {
 public:
  const dfa_table *states;
  const guess_arc *arcs;
  int state;
  double score;
  
 guess_dfa (const dfa_table stable[], const guess_arc *atable) :
  states(stable), arcs(atable)
  {
    state = 0;
    score = 1.0;
  }
};

class JapaneseCode
{
 public:
  enum Type {ASCII, JIS, EUC, SJIS, UNICODE, UTF8 };
  enum Type guess_jp(const char* buf, int buflen);
  
  JapaneseCode () {
    eucj = new guess_dfa(guess_eucj_st, guess_eucj_ar);
    sjis = new guess_dfa(guess_sjis_st, guess_sjis_ar);
    utf8 = new guess_dfa(guess_utf8_st, guess_utf8_ar);
    last_JIS_escape = false;
  }
  
  ~JapaneseCode () {
    if (eucj) delete eucj;
    if (sjis) delete sjis;
    if (utf8) delete utf8;
  }
  
 protected:
  guess_dfa *eucj;
  guess_dfa *sjis;
  guess_dfa *utf8;
  
  bool last_JIS_escape;
};

#define DFA_NEXT(dfa, ch)                               \
    do {                                                \
        int arc__;                                      \
        if (dfa->state >= 0) {                          \
            arc__ = dfa->states[dfa->state][ch];        \
            if (arc__ < 0) {                            \
                dfa->state = -1;                        \
            } else {                                    \
                dfa->state = dfa->arcs[arc__].next;     \
                dfa->score *= dfa->arcs[arc__].score;   \
            }                                           \
        }                                               \
    } while (0)

#define DFA_ALIVE(dfa)  (dfa->state >= 0)

#endif  /* GUESS_JA_H */
