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/*
 *  File:       basic_dfa_spec.hh
 *              $Id: basic_dfa_spec.hh,v 1.5 2002/06/26 20:45:36 alec Exp $
 *
 *  Author:     Alec Panovici (alecu@email.com)
 * 
 *  Comments:
 *
 *  Revision history:
 *
 *  $Log: basic_dfa_spec.hh,v $
 *  Revision 1.5  2002/06/26 20:45:36  alec
 *  g++ 3.x happy
 *
 *  Revision 1.4  2002/05/27 02:58:35  alec
 *  doc update
 *
 *  Revision 1.3  2002/05/01 16:32:14  alec
 *  dfa ok. huh !
 *
 *  Revision 1.2  2002/05/01 09:18:26  alec
 *  - vBitset fixes
 *  - FOLLOWPOS written (not tested yet)
 *
 *  Revision 1.1  2002/04/30 16:26:38  alec
 *  my big endian will eat your little endian
 *
 */


/*
  Copyright (C) 2002 Alexandru Panoviciu (alecu@email.com)

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#ifndef __BASIC_DFA_SPEC_HH__
#define __BASIC_DFA_SPEC_HH__

#include 
#include 
using namespace std;

#include "debug.h"

/**
 * This class contains the transition table for a DFA that resulted from a
 * scanner lexical state. One such object is created by an instance of
 * BasicDfaGenerator for each regexp parse tree resulted from the scanner's
 * section.
 */
class BasicDfaSpec
{
public:

  /**
   * Describes a transition in the transition table.
   */
  typedef struct t_Transition
  {
    /**
     * The input character on which this transition is taken.
     */
    unsigned char on;

    /**
     * The target state of this transition.
     */
    unsigned int to;

    t_Transition () {}
    t_Transition (unsigned char on_, unsigned int to_) :
      on(on_), to(to_)
    {}
    
  } Transition;
  
  /**
   * This is a DFA state.
   */
  typedef struct t_State
  {

    t_State () : isFinal(false), tokId(0)
    {}
    
    void addTransition (unsigned char on, unsigned int to)
    {
      transitions.push_back(Transition(on, to));
    }

#ifdef DEBUG
    void dump (ostream &os);
#endif
    
    /**
     * The "valid" transitions from this state. We assume that if a transitions
     * on a certain input character isn't here then it defaults to the "error"
     * transition.
     */
    vector transitions;
    
    /**
     * True if this is an accepting state.
     */
    bool isFinal;

    /**
     * If this state is an accepting state, this indicates the matched token's
     * id.
     */
    int tokId;
  } State;

  /**
   * Creates a new BasicDfaSpec object with the given name. The name is that
   * of the corresponding scanner lexical state.
   */
  BasicDfaSpec (const string &name_) : name(name_) {}

#ifdef DEBUG
  void dump (ostream &os);
#endif

  /**
   * The name of this DFA.
   */
  string name;

  /**
   * The transitions table of the DFA. At index i, the State object contains
   * the transitions the automaton can take while in state i.
   */
  vector states;
};

#endif /* #ifndef __BASIC_DFA_SPEC_HH__ */