//
// 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.


#include "parallel/InteriorBoundary.h"
#include "parallel/ElementObjectDatabase.h"
#include "FiniteElemSpace.h"
#include "BasisFunction.h"
#include "Serializer.h"
#include "VertexVector.h"

namespace AMDiS {

  using namespace std;


  void InteriorBoundary::create(MPI::Intracomm &mpiComm,
				ElementObjectDatabase &elObjDb)
  { 
    FUNCNAME("InteriorBoundary::clear()");

    own.clear();
    other.clear();
    periodic.clear();

    Mesh *mesh = elObjDb.getMesh();
    TEST_EXIT_DBG(mesh)("Should not happen!\n");

    int mpiRank = mpiComm.Get_rank();

    // === Create interior boundary data structure. ===
    
    for (int geoPos = 0; geoPos < mesh->getDim(); geoPos++) {
      GeoIndex geoIndex = INDEX_OF_DIM(geoPos, mesh->getDim());

      while (elObjDb.iterate(geoIndex)) {
	map<int, ElementObjectData>& objData = elObjDb.getIterateData();
	if (!(objData.count(mpiRank) && objData.size() > 1))
	  continue;

	int owner = elObjDb.getIterateOwner();
	ElementObjectData& rankBoundEl = objData[mpiRank];
	
	AtomicBoundary bound;
	bound.maxLevel = elObjDb.getIterateMaxLevel();
	bound.rankObj.el = elObjDb.getElementPtr(rankBoundEl.elIndex);
	bound.rankObj.elIndex = rankBoundEl.elIndex;
	bound.rankObj.elType = elObjDb.getElementType(rankBoundEl.elIndex);
	bound.rankObj.subObj = geoIndex;
	bound.rankObj.ithObj = rankBoundEl.ithObject;
	
	if (geoIndex == FACE) {
	  for (int edgeNo = 0; edgeNo < 3; edgeNo++) {
	    int edgeOfFace = 
	      bound.rankObj.el->getEdgeOfFace(bound.rankObj.ithObj, edgeNo);
	    
	    bound.rankObj.excludedSubstructures.push_back(make_pair(EDGE, edgeOfFace));
	  }
	}
	
	
	if (owner == mpiRank) {
	  for (map<int, ElementObjectData>::iterator it2 = objData.begin();
	       it2 != objData.end(); ++it2) {
	    if (it2->first == mpiRank)
	      continue;
	    
	    bound.neighObj.el = elObjDb.getElementPtr(it2->second.elIndex);
	    bound.neighObj.elIndex = it2->second.elIndex;
	    bound.neighObj.elType = elObjDb.getElementType(it2->second.elIndex);
	    bound.neighObj.subObj = geoIndex;
	    bound.neighObj.ithObj = it2->second.ithObject;
	    
	    bound.type = INTERIOR;
	    
	    AtomicBoundary& b = getNewOwn(it2->first);
	    b = bound;
	    if (geoIndex == EDGE)
	      b.neighObj.reverseMode = 
		elObjDb.getEdgeReverseMode(rankBoundEl, it2->second);
	    if (geoIndex == FACE)
	      b.neighObj.reverseMode = 
		elObjDb.getFaceReverseMode(rankBoundEl, it2->second);
	  }
	  
	} else {
	  TEST_EXIT_DBG(objData.count(owner) == 1)
	    ("Should not happen!\n");
	  
	  ElementObjectData& ownerBoundEl = objData[owner];
	  
	  bound.neighObj.el = elObjDb.getElementPtr(ownerBoundEl.elIndex);
	  bound.neighObj.elIndex = ownerBoundEl.elIndex;
	  bound.neighObj.elType = -1;
	  bound.neighObj.subObj = geoIndex;
	  bound.neighObj.ithObj = ownerBoundEl.ithObject;
	  
	  bound.type = INTERIOR;
	  
	  AtomicBoundary& b = getNewOther(owner);
	  b = bound;	    
	  if (geoIndex == EDGE)
	    b.rankObj.reverseMode =
	      elObjDb.getEdgeReverseMode(rankBoundEl, ownerBoundEl);
	  if (geoIndex == FACE)
	    b.rankObj.reverseMode = 
	      elObjDb.getFaceReverseMode(rankBoundEl, ownerBoundEl);
	}
      }
    }


    // === Create periodic boundary data structure. ===

    for (PerBoundMap<DegreeOfFreedom>::iterator it = elObjDb.getPeriodicVertices().begin();
	 it != elObjDb.getPeriodicVertices().end(); ++it) {
      if (elObjDb.isInRank(it->first.first, mpiRank) == false)
	continue;

      ElementObjectData& perDofEl0 = 
	elObjDb.getElementsInRank(it->first.first)[mpiRank];

      for (map<int, ElementObjectData>::iterator elIt = elObjDb.getElementsInRank(it->first.second).begin();
	   elIt != elObjDb.getElementsInRank(it->first.second).end(); ++elIt) {

	int otherElementRank = elIt->first;
	ElementObjectData& perDofEl1 = elIt->second;

	AtomicBoundary bound;
	bound.rankObj.el = elObjDb.getElementPtr(perDofEl0.elIndex);
	bound.rankObj.elIndex = perDofEl0.elIndex;
	bound.rankObj.elType = elObjDb.getElementType(perDofEl0.elIndex);
	bound.rankObj.subObj = VERTEX;
	bound.rankObj.ithObj = perDofEl0.ithObject;

	bound.neighObj.el = elObjDb.getElementPtr(perDofEl1.elIndex);
	bound.neighObj.elIndex = perDofEl1.elIndex;
	bound.neighObj.elType = elObjDb.getElementType(perDofEl1.elIndex);
	bound.neighObj.subObj = VERTEX;
	bound.neighObj.ithObj = perDofEl1.ithObject;

	bound.type = it->second;

	AtomicBoundary& b = getNewPeriodic(otherElementRank);
	b = bound;	    
      }
    }


    for (PerBoundMap<DofEdge>::iterator it = elObjDb.getPeriodicEdges().begin();
	 it != elObjDb.getPeriodicEdges().end(); ++it) {
      if (elObjDb.isInRank(it->first.first, mpiRank) == false)
	continue;

      ElementObjectData& perEdgeEl0 = elObjDb.getElementsInRank(it->first.first)[mpiRank];

      for (map<int, ElementObjectData>::iterator elIt = elObjDb.getElementsInRank(it->first.second).begin();
 	   elIt != elObjDb.getElementsInRank(it->first.second).end(); ++elIt) {
      
	int otherElementRank = elIt->first;
	ElementObjectData& perEdgeEl1 = elIt->second;

	AtomicBoundary bound;	    	    
	bound.rankObj.el = elObjDb.getElementPtr(perEdgeEl0.elIndex);
	bound.rankObj.elIndex = perEdgeEl0.elIndex;
	bound.rankObj.elType = elObjDb.getElementType(perEdgeEl0.elIndex);
	bound.rankObj.subObj = EDGE;
	bound.rankObj.ithObj = perEdgeEl0.ithObject;
	
	bound.neighObj.el = elObjDb.getElementPtr(perEdgeEl1.elIndex);
	bound.neighObj.elIndex = perEdgeEl1.elIndex;
	bound.neighObj.elType = elObjDb.getElementType(perEdgeEl1.elIndex);
	bound.neighObj.subObj = EDGE;
	bound.neighObj.ithObj = perEdgeEl1.ithObject;
	
	bound.type = it->second;
	
	AtomicBoundary& b = getNewPeriodic(otherElementRank);
	b = bound;
     
	if (mpiRank > otherElementRank)
	  b.neighObj.reverseMode = 
	    elObjDb.getEdgeReverseMode(perEdgeEl0, perEdgeEl1);
	else
	  b.rankObj.reverseMode = 
	    elObjDb.getEdgeReverseMode(perEdgeEl0, perEdgeEl1);
      }
    }


    for (PerBoundMap<DofFace>::iterator it = elObjDb.getPeriodicFaces().begin();
	 it != elObjDb.getPeriodicFaces().end(); ++it) {
      if (elObjDb.isInRank(it->first.first, mpiRank) == false)
	continue;

      TEST_EXIT_DBG(elObjDb.getElements(it->first.first).size() == 1)
 	("Should not happen!\n");
      TEST_EXIT_DBG(elObjDb.getElements(it->first.second).size() == 1)
 	("Should not happen!\n");

      ElementObjectData& perFaceEl0 = elObjDb.getElementsInRank(it->first.first)[mpiRank];

      for (map<int, ElementObjectData>::iterator elIt = elObjDb.getElementsInRank(it->first.second).begin();
 	   elIt != elObjDb.getElementsInRank(it->first.second).end(); ++elIt) {
      
	int otherElementRank = elIt->first;
	ElementObjectData& perFaceEl1 = elIt->second;

	AtomicBoundary bound;	    	    
	bound.rankObj.el = elObjDb.getElementPtr(perFaceEl0.elIndex);
	bound.rankObj.elIndex = perFaceEl0.elIndex;
	bound.rankObj.elType = elObjDb.getElementType(perFaceEl0.elIndex);
	bound.rankObj.subObj = FACE;
	bound.rankObj.ithObj = perFaceEl0.ithObject;
	
	bound.neighObj.el = elObjDb.getElementPtr(perFaceEl1.elIndex);
	bound.neighObj.elIndex = perFaceEl1.elIndex;
	bound.neighObj.elType = elObjDb.getElementType(perFaceEl1.elIndex);
	bound.neighObj.subObj = FACE;
	bound.neighObj.ithObj = perFaceEl1.ithObject;
	
	bound.type = it->second;
	
	AtomicBoundary& b = getNewPeriodic(otherElementRank);
	b = bound;
     
	if (mpiRank > otherElementRank)
	  b.neighObj.reverseMode = 
	    elObjDb.getFaceReverseMode(perFaceEl0, perFaceEl1);
	else
	  b.rankObj.reverseMode = 
	    elObjDb.getFaceReverseMode(perFaceEl0, perFaceEl1);
      }
    }
    

    // === Once we have this information, we must care about the order of the ===
    // === atomic bounds in the three boundary handling object. Eventually    ===
    // === all the boundaries have to be in the same order on both ranks that ===
    // === share the bounday.                                                 ===

    StdMpi<vector<AtomicBoundary> > stdMpi(mpiComm);
    stdMpi.send(own);
    stdMpi.recv(other);
    stdMpi.startCommunication();


    // === The information about all neighbouring boundaries has been         ===
    // === received. So the rank tests if its own atomic boundaries are in    ===
    // === the same order. If not, the atomic boundaries are swaped to the    ===
    // === correct order.                                                     ===

    for (RankToBoundMap::iterator rankIt = other.begin();
	 rankIt != other.end(); ++rankIt) {

      // === We have received from rank "rankIt->first" the ordered list of   ===
      // === element indices. Now, we have to sort the corresponding list in  ===
      // === this rank to get the same order.                                 ===
     
      for (unsigned int j = 0; j < rankIt->second.size(); j++) {

	// If the expected object is not at place, search for it.

	BoundaryObject &recvedBound = stdMpi.getRecvData()[rankIt->first][j].rankObj;

	if ((rankIt->second)[j].neighObj != recvedBound) {
	  unsigned int k = j + 1;

	  for (; k < rankIt->second.size(); k++)
 	    if ((rankIt->second)[k].neighObj == recvedBound)
	      break;

	  // The element must always be found, because the list is just in
	  // another order.
	  TEST_EXIT_DBG(k < rankIt->second.size())("Should never happen!\n");

	  // Swap the current with the found element.
	  AtomicBoundary tmpBound = (rankIt->second)[k];
	  (rankIt->second)[k] = (rankIt->second)[j];
	  (rankIt->second)[j] = tmpBound;	
	}
      }
    }


    // === Do the same for the periodic boundaries. ===

    if (periodic.size() > 0) {
      stdMpi.clear();

      RankToBoundMap sendBounds, recvBounds;
      for (RankToBoundMap::iterator rankIt = periodic.begin();
	   rankIt != periodic.end(); ++rankIt) {

	if (rankIt->first == mpiRank)
	  continue;

	if (rankIt->first < mpiRank)
	  sendBounds[rankIt->first] = rankIt->second;
	else
	  recvBounds[rankIt->first] = rankIt->second;	
      }

      stdMpi.send(sendBounds);
      stdMpi.recv(recvBounds);
      stdMpi.startCommunication();

      for (RankToBoundMap::iterator rankIt = periodic.begin();
	   rankIt != periodic.end(); ++rankIt) {

 	if (rankIt->first <= mpiRank)
 	  continue;
  
	for (unsigned int j = 0; j < rankIt->second.size(); j++) {
	  BoundaryObject &recvRankObj = 
	    stdMpi.getRecvData()[rankIt->first][j].rankObj;
	  BoundaryObject &recvNeighObj = 
	    stdMpi.getRecvData()[rankIt->first][j].neighObj;

	  if (periodic[rankIt->first][j].neighObj != recvRankObj ||
	      periodic[rankIt->first][j].rankObj != recvNeighObj) {
	    unsigned int k = j + 1;	    
	    for (; k < rankIt->second.size(); k++)
	      if (periodic[rankIt->first][k].neighObj == recvRankObj &&
		  periodic[rankIt->first][k].rankObj == recvNeighObj)
		break;
	    
	    // The element must always be found, because the list is just in 
	    // another order.
	    TEST_EXIT_DBG(k < rankIt->second.size())("Should never happen!\n");

	    // Swap the current with the found element.
	    AtomicBoundary tmpBound = (rankIt->second)[k];
	    (rankIt->second)[k] = (rankIt->second)[j];
	    (rankIt->second)[j] = tmpBound;	
	  } 
	}
      }     
    } // periodicBoundary.boundary.size() > 0
  }


  void InteriorBoundary::serialize(ostream &out)
  {
    serialize(out, own);
    serialize(out, other);
    serialize(out, periodic);
  }


  void InteriorBoundary::serialize(ostream &out,
				   RankToBoundMap& boundary)
  {
    FUNCNAME("InteriorBoundary::serialize()");

    int mSize = boundary.size();
    SerUtil::serialize(out, mSize);
    for (RankToBoundMap::iterator it = boundary.begin(); 
	 it != boundary.end(); ++it) {
      int rank = it->first;
      int boundSize = it->second.size();
      SerUtil::serialize(out, rank);
      SerUtil::serialize(out, boundSize);
      for (int i = 0; i < boundSize; i++) {
	AtomicBoundary &bound = (it->second)[i];

	SerUtil::serialize(out, bound.rankObj.elIndex);
	SerUtil::serialize(out, bound.rankObj.elType);
	SerUtil::serialize(out, bound.rankObj.subObj);
	SerUtil::serialize(out, bound.rankObj.ithObj);
	SerUtil::serialize(out, bound.rankObj.reverseMode);
	serializeExcludeList(out, bound.rankObj.excludedSubstructures);

	SerUtil::serialize(out, bound.neighObj.elIndex);
	SerUtil::serialize(out, bound.neighObj.elType);
	SerUtil::serialize(out, bound.neighObj.subObj);
	SerUtil::serialize(out, bound.neighObj.ithObj);
	SerUtil::serialize(out, bound.neighObj.reverseMode);
	serializeExcludeList(out, bound.neighObj.excludedSubstructures);

	SerUtil::serialize(out, bound.type);
      }
    }
  }


  void InteriorBoundary::deserialize(istream &in, Mesh *mesh)				     
  {
    map<int, Element*> elIndexMap;
    mesh->getElementIndexMap(elIndexMap);

    deserialize(in, own, elIndexMap);
    deserialize(in, other, elIndexMap);
    deserialize(in, periodic, elIndexMap);
  }


  void InteriorBoundary::deserialize(istream &in, 
				     RankToBoundMap& boundary,
				     map<int, Element*> &elIndexMap)
  {
    FUNCNAME("InteriorBoundary::deserialize()");

    int mSize = 0;
    SerUtil::deserialize(in, mSize);
    for (int i = 0; i < mSize; i++) {
      int rank = 0;
      int boundSize = 0;
      SerUtil::deserialize(in, rank);
      SerUtil::deserialize(in, boundSize);

      boundary[rank].resize(boundSize);
      for (int i = 0; i < boundSize; i++) {
	AtomicBoundary &bound = boundary[rank][i];

	SerUtil::deserialize(in, bound.rankObj.elIndex);
	SerUtil::deserialize(in, bound.rankObj.elType);
	SerUtil::deserialize(in, bound.rankObj.subObj);
	SerUtil::deserialize(in, bound.rankObj.ithObj);
	SerUtil::deserialize(in, bound.rankObj.reverseMode);
	deserializeExcludeList(in, bound.rankObj.excludedSubstructures);

	SerUtil::deserialize(in, bound.neighObj.elIndex);
	SerUtil::deserialize(in, bound.neighObj.elType);
	SerUtil::deserialize(in, bound.neighObj.subObj);
	SerUtil::deserialize(in, bound.neighObj.ithObj);
	SerUtil::deserialize(in, bound.neighObj.reverseMode);
	deserializeExcludeList(in, bound.neighObj.excludedSubstructures);

	SerUtil::deserialize(in, bound.type);

	TEST_EXIT_DBG(elIndexMap.count(bound.rankObj.elIndex) == 1)
	  ("Cannot find element with index %d for deserialization!\n", 
	   bound.rankObj.elIndex);

	TEST_EXIT_DBG(elIndexMap[bound.rankObj.elIndex]->getIndex() == 
		      bound.rankObj.elIndex)("Should not happen!\n");

	bound.rankObj.el = elIndexMap[bound.rankObj.elIndex];

	// For the case of periodic interior boundaries, a rank may have an
	// boundary with itself. In this case, also the pointer to the neighbour
	// object must be set correctly.
	if (elIndexMap.count(bound.neighObj.elIndex))
	  bound.neighObj.el = elIndexMap[bound.neighObj.elIndex];
	else
	  bound.neighObj.el = NULL;
      }
    }
  }


  AtomicBoundary& InteriorBoundary::getNewOwn(int rank)
  {
    int size = own[rank].size();
    own[rank].resize(size + 1);
    return own[rank][size];
  }


  AtomicBoundary& InteriorBoundary::getNewOther(int rank)
  {
    int size = other[rank].size();
    other[rank].resize(size + 1);
    return other[rank][size];
  }


  AtomicBoundary& InteriorBoundary::getNewPeriodic(int rank)
  {
    int size = periodic[rank].size();
    periodic[rank].resize(size + 1);
    return periodic[rank][size];
  }


  void InteriorBoundary::serializeExcludeList(ostream &out, 
					      ExcludeList &list)
  {
    int size = list.size();
    SerUtil::serialize(out, size);
    for (int i = 0; i < size; i++) {
      SerUtil::serialize(out, list[i].first);
      SerUtil::serialize(out, list[i].second);
    }
  }


  void InteriorBoundary::deserializeExcludeList(istream &in, 
						ExcludeList &list)
  {
    int size = 0;
    SerUtil::deserialize(in, size);
    list.resize(0);
    list.reserve(size);

    for (int i = 0; i < size; i++) {
      GeoIndex a;
      int b;

      SerUtil::deserialize(in, a);
      SerUtil::deserialize(in, b);
      list.push_back(make_pair(a, b));
    }
  }

}