/* -*- C++ -*-

 * lemon/counter.h - 

 * Part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#ifndef LEMON_COUNTER_H

#define LEMON_COUNTER_H

#include <string>

#include <iostream>

///\ingroup timecount

///\file

///\brief Tools for counting steps and events

namespace lemon 

{

  template<class P> class _SubNoCounter;

  template<class P>

  class _SubCounter 

  {

    P &_parent;

    std::string _title;

    std::ostream &_os;

    int count;

  public:

    typedef _SubCounter<_SubCounter<P> > SubCounter;

    typedef _SubNoCounter<_SubCounter<P> > SubNoCounter;

    _SubCounter(P &parent)

      : _parent(parent), _title(), _os(std::cerr), count(0) {}

    _SubCounter(P &parent,std::string title,std::ostream &os=std::cerr)

      : _parent(parent), _title(title), _os(os), count(0) {}

    _SubCounter(P &parent,const char *title,std::ostream &os=std::cerr)

      : _parent(parent), _title(title), _os(os), count(0) {}

    ~_SubCounter() { 

      _os << _title << count <<std::endl;

      _parent+=count;

    }

    _SubCounter &operator++() { count++; return *this;}

    int operator++(int) { return count++; }

    _SubCounter &operator--() { count--; return *this;}

    int operator--(int) { return count--; }

    _SubCounter &operator+=(int c) { count+=c; return *this;}

    _SubCounter &operator-=(int c) { count-=c; return *this;}

    void reset(int c=0) {count=c;}

    operator int() {return count;}

  };

  template<class P>

  class _SubNoCounter 

  {

    P &_parent;

  public:

    typedef _SubNoCounter<_SubNoCounter<P> > SubCounter;

    typedef _SubNoCounter<_SubNoCounter<P> > SubNoCounter;

    _SubNoCounter(P &parent) :_parent(parent) {}

    _SubNoCounter(P &parent,std::string title,std::ostream &os=std::cerr) 

      :_parent(parent) {}

    _SubNoCounter(P &parent,const char *title,std::ostream &os=std::cerr)

      :_parent(parent) {}

    ~_SubNoCounter() {}

    _SubNoCounter &operator++() { ++_parent; return *this;}

    int operator++(int) { _parent++; return 0;}

    _SubNoCounter &operator--() { --_parent; return *this;}

    int operator--(int) { _parent--; return 0;}

    _SubNoCounter &operator+=(int c) { _parent+=c; return *this;}

    _SubNoCounter &operator-=(int c) { _parent-=c; return *this;}

    void reset(int c=0) {}

    operator int() {return 0;}

  };

  /// \addtogroup timecount

  /// @{

  ///A counter class

  ///This class makes it easier to count certain events. You can increment

  ///or decrement the counter using operator++ and operator--.

  ///A report is automatically printed on destruction.

  class Counter 

  {

    std::string _title;

    std::ostream &_os;

    int count;

  public:

    ///\e

    ///\todo document please.

    ///

    typedef _SubCounter<Counter> SubCounter;

    ///\e

    ///\todo document please.

    ///

    typedef _SubNoCounter<Counter> SubNoCounter;

    ///\e

    Counter() : _title(), _os(std::cerr), count(0) {}

    ///\e

    Counter(std::string title,std::ostream &os=std::cerr) 

      : _title(title), _os(os), count(0) {}

    ///\e

    Counter(const char *title,std::ostream &os=std::cerr)

      : _title(title), _os(os), count(0) {}

    ///Destructor. Prints the given title and the value of the counter.

    ~Counter() {

      _os << _title << count <<std::endl;

    }

    ///\e

    Counter &operator++() { count++; return *this;}

    ///\e

    int operator++(int) { return count++;}

    ///\e

    Counter &operator--() { count--; return *this;}

    ///\e

    int operator--(int) { return count--;}

    ///\e

    Counter &operator+=(int c) { count+=c; return *this;}

    ///\e

    Counter &operator-=(int c) { count-=c; return *this;}

    ///\e

    void reset(int c=0) {count=c;}

    ///\e

    operator int() {return count;}

  };

  ///'Do nothing' version of \ref Counter

  ///'Do nothing' version of \ref Counter.

  ///\sa Counter

  class NoCounter

  {

  public:

    typedef _SubNoCounter<NoCounter> SubCounter;

    typedef _SubNoCounter<NoCounter> SubNoCounter;

    NoCounter() {}

    NoCounter(std::string title,std::ostream &os=std::cerr) {}

    NoCounter(const char *title,std::ostream &os=std::cerr) {}

    NoCounter &operator++() { return *this; }

    int operator++(int) { return 0; }

    NoCounter &operator--() { return *this; }

    int operator--(int) { return 0; }

    NoCounter &operator+=(int c) { return *this;}

    NoCounter &operator-=(int c) { return *this;}

    void reset(int c=0) {}

    operator int() {return 0;}

  };

  ///@}

}

#endif