// ============================================================================
// ==                                                                        ==
// == 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 InteriorBoundary.h */

#ifndef AMDIS_INTERIORBOUNDARY_H
#define AMDIS_INTERIORBOUNDARY_H

#include <vector>
#include <map>

#include "AMDiS_fwd.h"
#include "BoundaryObject.h"
#include "parallel/MeshLevelData.h"
#include "parallel/ParallelTypes.h"

namespace AMDiS {

  using namespace std;

  /** \brief
   * Defines the interior boundary, i.e. a bound within the domain. It is used for
   * the classical domain decomposition parallelization.
   */
  class InteriorBoundary {
  public:
    void create(MPI::Intracomm &mpiComm,
		ElementObjectDatabase &elObjDb);

    /// Writes this object to a file.
    void serialize(ostream &out);

    /// Reads the state of an interior boundary from a file.
    void deserialize(istream &in, map<int, Element*> &elIndexMap);

    RankToBoundMap& getOwn()
    {
      return own;
    }
 
    RankToBoundMap& getOther()
    {
      return other;
    }

    RankToBoundMap& getPeriodic()
    {
      return periodic;
    }

    bool hasPeriodic()
    {
      return static_cast<bool>(periodic.size());
    }

  private:
    AtomicBoundary& getNewOwn(int rank);

    AtomicBoundary& getNewOther(int rank);

    AtomicBoundary& getNewPeriodic(int rank);

    void serializeExcludeList(ostream &out, ExcludeList &list);

    void deserializeExcludeList(istream &in, ExcludeList &list);    

  private:
    RankToBoundMap own, other, periodic;

    friend class ParallelDebug;

  public:
    /// Iterator for the interior boundary object.
    class iterator {      
    public:
      iterator(RankToBoundMap &b, int traverseLevel = 0)
	: bound(b),
	  level(traverseLevel)
      {
	reset();
      }

      /// Set the iterator to the first position.
      void reset()
      {
	mapIt = bound.begin();
	nextNonempty();
      }

      /// Test if iterator is at the final position.
      bool end() const
      {
	return (mapIt == bound.end());
      }

      /// Move iterator to the next position.
      void operator++()
      {
	do {
	  ++vecIt;
	} while (vecIt->maxLevel < level && vecIt != mapIt->second.end());

	if (vecIt == mapIt->second.end()) {
	  ++mapIt;
	  nextNonempty();
	}	
      }

      inline AtomicBoundary& operator*()
      {
	return *vecIt;
      }

      inline AtomicBoundary* operator->()
      {
	return &(*vecIt);
      }

      void nextRank()
      {
	++mapIt;
	nextNonempty();
      }

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

    protected:

      inline void nextNonempty()
      {
	do {
	  // Return, we are at the end.
	  if (mapIt == bound.end())
	    return;
	  
	  // Search for the next non empty boundary map.
	  while (mapIt->second.size() == 0) {
	    ++mapIt;
	    if (mapIt == bound.end())
	      return;	  
	  }
	  
	  vecIt = mapIt->second.begin();
	  
	  // Search for the next atomic boundary on the mesh level
	  while (vecIt->maxLevel < level && vecIt != mapIt->second.end())
	    ++vecIt;
	  
	  // If vector iterator is not at the end, we have found one and
	  // can return.
	  if (vecIt != mapIt->second.end())
	    return;
	  
	  // In this case, no boundary on the given level is found, continue
	  // with next rank.
	  ++mapIt;
	} while (true);
      }

    protected:
      RankToBoundMap::iterator mapIt;

      vector<AtomicBoundary>::iterator vecIt;

      RankToBoundMap &bound;

      int level;
    };
  };
}

#endif // AMDIS_INTERIORBOUNDARY_H