/* -*- 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