/* -*- C++ -*-

  * lemon/concept/matrix_maps.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_CONCEPT_MATRIX_MAPS_H

 #define LEMON_CONCEPT_MATRIX_MAPS_H

 #include <lemon/utility.h>

 #include <lemon/concept_check.h>

 ///\ingroup concept

 ///\file

 ///\brief MatrixMap concepts checking classes for testing and documenting.

 namespace lemon {

   namespace concept {

     /// \addtogroup concept

     /// @{

     /// Readable matrix map concept

     template <typename K1, typename K2, typename V>

     class ReadMatrixMap

     {

     public:

       /// Map's first key type.

       typedef K1 FirstKey;    

       /// Map's second key type.

       typedef K2 SecondKey;    

       /// \brief Map's value type. 

       /// (The type of objects associated with the pairs of keys).

       typedef V Value;

       // \bug Value don't need to be default constructible.

       /// Returns the value associated with a key.

       Value operator()(const FirstKey&, const SecondKey&) const {

 	return Value();

       }

       template <typename _ReadMatrixMap>

       struct Constraints {

 	void constraints() {

 	  Value val = m(first_key, second_key);

 	  val = m(first_key, second_key);

 	  typename _ReadMatrixMap::Value own_val = 

 	    m(own_first_key, own_second_key); 

 	  own_val = m(own_first_key, own_second_key);

 	  ignore_unused_variable_warning(val);

 	  ignore_unused_variable_warning(own_val);

 	}

 	FirstKey& first_key;

 	SecondKey& second_key;	

 	typename _ReadMatrixMap::FirstKey& own_first_key;

 	typename _ReadMatrixMap::SecondKey& own_second_key;

 	_ReadMatrixMap& m;

       };

     };

     /// Writable map concept

     template <typename K1, typename K2, typename V>

     class WriteMatrixMap {

     public:

       /// Map's first key type.

       typedef K1 FirstKey;    

       /// Map's second key type.

       typedef K2 SecondKey;    

       /// \brief Map's value type. 

       /// (The type of objects associated with the pairs of keys).

       typedef V Value;

       /// Sets the value associated with the pair of keys.

       void set(const FirstKey&, const SecondKey& ,const Value&) {}

       template <typename _WriteMatrixMap>

       struct Constraints {

 	void constraints() {

 	  // No constraints for constructor.

 	  m.set(first_key, second_key, val);

 	  m.set(own_first_key, own_second_key, own_val);

 	}

 	Value& val;

 	typename _WriteMatrixMap::Value own_val;

 	FirstKey& first_key;

 	SecondKey& second_key;

 	typename _WriteMatrixMap::FirstKey& own_first_key;

 	typename _WriteMatrixMap::SecondKey& own_second_key;

 	_WriteMatrixMap& m;

       };

     };

     ///Read/Writable map concept

     template<typename K1, typename K2, typename V>

     class ReadWriteMatrixMap 

       : public ReadMatrixMap<K1, K2, V>, public WriteMatrixMap<K1, K2, V> {

     public:

       /// Map's first key type.

       typedef K1 FirstKey;    

       /// Map's second key type.

       typedef K2 SecondKey;    

       /// \brief Map's value type. 

       /// (The type of objects associated with the pairs of keys).

       typedef V Value;

       /// Returns the value associated with a pair of keys.

       Value operator()(const FirstKey&, const SecondKey&) const { 

 	return Value(); 

       }

       /// Sets the value associated with the pair of keys.

       void set(const FirstKey&, const SecondKey& ,const Value&) {}

       template<typename _ReadWriteMatrixMap>

       struct Constraints {

 	void constraints() {

 	  checkConcept<ReadMatrixMap<K1, K2, V>, _ReadWriteMatrixMap >();

 	  checkConcept<WriteMatrixMap<K1, K2, V>, _ReadWriteMatrixMap >();

 	}

       };

     };

     ///Dereferable matrix map concept

     template<typename K1, typename K2, typename V, typename R, typename CR>

     class ReferenceMatrixMap : public ReadWriteMatrixMap<K1, K2, V>

     {

     public:

       /// Tag for reference maps.

       typedef True ReferenceMapTag;

       /// Map's first key type.

       typedef K1 FirstKey;    

       /// Map's second key type.

       typedef K1 SecondKey;    

       /// Map's value type. (The type of objects associated with the keys).

       typedef V Value;

       /// Map's reference type.

       typedef R Reference;

       /// Map's const reference type.

       typedef CR ConstReference;

     protected:

       Value tmp;

     public:

       ///Returns a reference to the value associated to a pair of keys.

       Reference operator()(const FirstKey&, const SecondKey&) { 

 	return tmp; 

       }

       ///Returns a const reference to the value associated to a pair of keys.

       ConstReference operator()(const FirstKey&, const SecondKey&) const { 

 	return tmp; 

       }

       /// Sets the value associated with the pair of keys.

       void set(const FirstKey&, const SecondKey& ,const Value&) {}

       // \todo rethink this concept

       template<typename _ReferenceMatrixMap>

       struct ReferenceMapConcept {

 	void constraints() {

 	  checkConcept<ReadWriteMatrixMap, _ReferenceMatrixMap >();

 	  m(first_key, second_key) = val;

 	  val  = m(first_key, second_key);

 	  m(first_key, second_key) = ref;

 	  ref = m(first_key, second_key);

 	  m(own_first_key, own_second_key) = own_val;

 	  own_val  = m(own_first_key, own_second_key);

 	  m(own_first_key, own_second_key) = own_ref;

 	  own_ref = m(own_first_key, own_second_key); 

 	}

 	typename _ReferenceMatrixMap::Key& own_first_key;

 	typename _ReferenceMatrixMap::Key& own_second_key;

 	typename _ReferenceMatrixMap::Value& own_val;

 	typename _ReferenceMatrixMap::Reference& own_ref;

 	FirstKey& first_key;

 	SecondKey& second_key;

 	Value& val;

 	Reference& ref;

 	_ReferenceMatrixMap& m;

       };

     };

     // @}

   } //namespace concept

 } //namespace lemon

 #endif // LEMON_CONCEPT_MATRIX_MAPS_H