// ============================================================================
// ==                                                                        ==
// == AMDiS - Adaptive multidimensional simulations                          ==
// ==                                                                        ==
// ==  http://www.amdis-fem.org                                              ==
// ==                                                                        ==
// ============================================================================
//
// Software License for AMDiS
//
// Copyright (c) 2010 Dresden University of Technology 
// All rights reserved.
// Authors: Simon Vey, Thomas Witkowski et al.
//
// This file is part of AMDiS
//
// See also license.opensource.txt in the distribution.



/** \file DofComm.h */

#ifndef AMDIS_DOF_COMM_H
#define AMDIS_DOF_COMM_H

#include <map>
#include "parallel/ParallelTypes.h"
#include "FiniteElemSpace.h"
#include "Global.h"

namespace AMDiS {

  using namespace std;

  class DofComm
  {
  public:
    DofComm() 
      : recvDofs(1),
	sendDofs(1),
	periodicDofs(0),
	meshLevel(-1),
	nLevel(0),
	levelData(NULL)
    {}
    
    typedef map<const FiniteElemSpace*, DofContainer> FeMapType;
    typedef FeMapType::iterator FeMapIter;
    typedef map<int, FeMapType> DataType;
    typedef DataType::iterator DataIter;
    // meshLevel: map[rank -> map[feSpace -> DofContainer]]
    typedef vector<DataType> LevelDataType;

    void init(int level, 
	      MeshLevelData &levelData, 
	      vector<const FiniteElemSpace*> &fe);

    void create(InteriorBoundary &boundary);

    LevelDataType& getSendDofs()
    {
      return sendDofs;
    }

    LevelDataType& getRecvDofs()
    {
      return recvDofs;
    }

    LevelDataType& getPeriodicDofs()
    {
      return periodicDofs;
    }

    // Writes all data of this object to an output stream.
    void serialize(ostream &out)
    {
      ERROR_EXIT("MUST BE IMPLEMENTED!\n");
    }

    // Reads the object data from an input stream.
    void deserialize(istream &in, 
		     map<const FiniteElemSpace*, map<int, const DegreeOfFreedom*> > dofIndexMap)
    {
      ERROR_EXIT("MUST BE IMPLEMENTED!\n");
    }

    int getNumberDofs(LevelDataType &data, 
		      int level, 
		      const FiniteElemSpace *feSpace,
		      bool countDouble = false);

  protected:
    void createContainer(RankToBoundMap &boundary, LevelDataType &data);

  protected:
    /// This map contains for each rank the list of DOFs the current rank must 
    /// end to exchange solution DOFs at the interior boundaries.
    LevelDataType sendDofs;

    /// This map contains on each rank the list of DOFs from which the current 
    /// rank will receive DOF values (i.e., this are all DOFs at an interior 
    /// boundary). The DOF indices are given in rank's local numbering.
    LevelDataType recvDofs;

    /// This map contains on each rank a list of DOFs along the interior bound-
    /// aries to communicate with other ranks. The DOF indices are given in rank's
    /// local numbering. Periodic boundaries within one subdomain are not 
    /// considered here. 
    LevelDataType periodicDofs;

    int meshLevel;

    int nLevel;

    MeshLevelData *levelData;

    vector<const FiniteElemSpace*> feSpaces;

    friend class Iterator;

  public:
    class Iterator
    {
    public:
      Iterator(LevelDataType &d,
	       const FiniteElemSpace *fe = NULL)
	: data(d),
	  dofCounter(-1),
	  traverseFeSpace(fe),
	  traverseLevel(0)
      {
	goFirst();
      }

      Iterator(LevelDataType &d,
	       int level,
	       const FiniteElemSpace *fe = NULL)
	: data(d),
	  dofCounter(-1),
	  traverseFeSpace(fe),
	  traverseLevel(level)
      {
	goFirst();
      }

      inline bool end()
      {
	return (dataIter == data[traverseLevel].end());
      }
      
      inline void nextRank()
      {
	do {
	  ++dataIter;
	} while (setNextFeMap() == false);
      }

      inline void nextFeSpace()
      {
	++feMapIter;
      }

      inline void next()
      {
	++feMapIter;
	if (feMapIter == dataIter->second.end()) {
	  do {
	    ++dataIter;
	  } while (setNextFeMap() == false);
	} else {
	  dofIter = feMapIter->second.begin();
	  dofCounter = 0;
	}
      }

      inline void beginDofIter(const FiniteElemSpace *fe = NULL)
      {
	FUNCNAME("DofComm::Iterator::beginDofIter()");

	if (fe != NULL) {
	  feMapIter = dataIter->second.begin();

	  while (feMapIter->first != fe &&
		 feMapIter != dataIter->second.end())
	    ++feMapIter;
	}

	if (feMapIter != dataIter->second.end()) {
	  dofIter = feMapIter->second.begin();
	  dofCounter = 0;
	}
      }

      inline bool endDofIter()
      {
	if (feMapIter == dataIter->second.end())
	  return true;

	return (dofIter == feMapIter->second.end());
      }
      
      inline void nextDof()
      {
	++dofIter;
	++dofCounter;
      }

      inline int getRank()
      {
	return dataIter->first;
      }

      inline const FiniteElemSpace* getFeSpace()
      {
	return feMapIter->first;
      }

      inline DofContainer& getDofs()
      {
	return feMapIter->second;
      }

      inline const DegreeOfFreedom* getDof()
      {
	return *dofIter;
      }

      inline DegreeOfFreedom getDofIndex()
      {
	return **dofIter;
      }

      inline int getDofCounter()
      {
	return dofCounter;
      }

    protected:
      void goFirst()
      {
	dataIter = data[traverseLevel].begin();

	while (setNextFeMap() == false)
	  ++dataIter;
      }

      bool setNextFeMap();

    protected:
      LevelDataType &data;
      
      DofComm::DataIter dataIter;
      
      DofComm::FeMapIter feMapIter;

      DofContainer::iterator dofIter;

      int dofCounter;

      const FiniteElemSpace *traverseFeSpace;

      int traverseLevel;
    };


  };

}

#endif // AMDIS_DOF_COMM_H