/***************************************************************************
                          DistributedGridTest.cpp  -  description
                             -------------------
    begin                : Sep 6, 2017
    copyright            : (C) 2017 by Tomas Oberhuber et al.
    email                : tomas.oberhuber@fjfi.cvut.cz
 ***************************************************************************/


#ifdef HAVE_GTEST  
#include <gtest/gtest.h>

#ifdef HAVE_MPI    

#include <TNL/Communicators/MpiCommunicator.h>
#include <TNL/Functions/MeshFunction.h>
#include <TNL/Meshes/DistributedMeshes/DistributedMesh.h>
#include <TNL/Meshes/DistributedMeshes/SubdomainOverlapsGetter.h>

#include "../../Functions/Functions.h"

using namespace TNL;
using namespace TNL::Containers;
using namespace TNL::Meshes;
using namespace TNL::Meshes::DistributedMeshes;
using namespace TNL::Functions;
using namespace TNL::Devices;
using namespace TNL::Communicators;


template<typename DofType>
void setDof_1D( DofType &dof, typename DofType::RealType value )
{
   for( int i = 0; i < dof.getSize(); i++ )
      dof[ i ] = value;
}

template<typename DofType>
void check_Boundary_1D(int rank, int nproc, const DofType& dof, typename DofType::RealType expectedValue)
{
    if(rank==0)//Left
    {
        EXPECT_EQ( dof[0], expectedValue) << "Left boundary test failed";
        return;
    }
    
    if(rank==(nproc-1))//Right
    {
        EXPECT_EQ( dof[dof.getSize()-1], expectedValue) << "Right boundary test failed";
        return;
    }
    
};

template<typename DofType>
void check_Overlap_1D(int rank, int nproc, const DofType& dof, typename DofType::RealType expectedValue)
{
    if( rank == 0 )//Left
    {
        EXPECT_EQ( dof[dof.getSize()-1], expectedValue) << "Left boundary node overlap test failed";
        return;
    }
    
    if( rank == ( nproc - 1 ) )
    {
        EXPECT_EQ( dof[0], expectedValue) << "Right boundary node overlap test failed";
        return;
    }
    
    EXPECT_EQ( dof[0], expectedValue) << "left overlap test failed";
    EXPECT_EQ( dof[dof.getSize()-1], expectedValue)<< "right overlap test failed";    
};

template<typename DofType>
void check_Inner_1D(int rank, int nproc, const DofType& dof, typename DofType::RealType expectedValue)
{
    for( int i = 1; i < ( dof.getSize()-2 ); i++ )
        EXPECT_EQ( dof[i], expectedValue) << " " << i;
};

/*
 * Light check of 1D distriover grid and its synchronization. 
 * Number of process is not limitated.
 * Overlap is limitated to 1
 * Only double is tested as dof Real type -- it may be changed, extend test
 * Global size is hardcoded as 10 -- it can be changed, extend test
 */

typedef MpiCommunicator CommunicatorType;
typedef Grid<1,double,Host,int> GridType;
typedef MeshFunction<GridType> MeshFunctionType;
typedef Vector<double,Host,int> DofType;
typedef typename GridType::Cell Cell;
typedef typename GridType::IndexType IndexType; 
typedef typename GridType::PointType PointType; 
typedef DistributedMesh<GridType> DistributedGridType;
     
class DistributedGridTest_1D : public ::testing::Test
{
   protected:

      DistributedMesh< GridType > *distributedGrid;
      DofType dof;

      SharedPointer< GridType > gridptr;
      SharedPointer< MeshFunctionType > meshFunctionPtr;

      MeshFunctionEvaluator< MeshFunctionType, ConstFunction< double, 1 > > constFunctionEvaluator;
      SharedPointer< ConstFunction< double, 1 >, Host > constFunctionPtr;

      MeshFunctionEvaluator< MeshFunctionType, LinearFunction< double, 1 > > linearFunctionEvaluator;
      SharedPointer< LinearFunction< double, 1 >, Host > linearFunctionPtr;

      int rank;
      int nproc;

      void SetUp()
      {
         int size=10;
         rank=CommunicatorType::GetRank(CommunicatorType::AllGroup);
         nproc=CommunicatorType::GetSize(CommunicatorType::AllGroup);

         PointType globalOrigin;
         PointType globalProportions;
         GridType globalGrid;

         globalOrigin.x()=-0.5;    
         globalProportions.x()=size;


         globalGrid.setDimensions(size);
         globalGrid.setDomain(globalOrigin,globalProportions);

         typename DistributedGridType::CoordinatesType overlap;
         overlap.setValue(1);
         distributedGrid=new DistributedGridType();

         typename DistributedGridType::SubdomainOverlapsType lowerOverlap, upperOverlap;
         distributedGrid->template setGlobalGrid<CommunicatorType>( globalGrid );
         //distributedGrid->setupGrid(*gridptr);    
         SubdomainOverlapsGetter< GridType, CommunicatorType >::
            getOverlaps( distributedGrid, lowerOverlap, upperOverlap, 1 );
         distributedGrid->setOverlaps( lowerOverlap, upperOverlap );

         distributedGrid->setupGrid(*gridptr);
         dof.setSize( gridptr->template getEntitiesCount< Cell >() );

         meshFunctionPtr->bind(gridptr,dof);

         constFunctionPtr->Number=rank;
      }
      
      void SetUpPeriodicBoundaries()
      {
         typename DistributedGridType::SubdomainOverlapsType lowerOverlap, upperOverlap;
         SubdomainOverlapsGetter< GridType, CommunicatorType >::
            getOverlaps( distributedGrid, lowerOverlap, upperOverlap, 1 );
         distributedGrid->setOverlaps( lowerOverlap, upperOverlap );
         distributedGrid->setupGrid(*gridptr);         
      }

      void TearDown()
      {
         delete distributedGrid;
      }
};

TEST_F( DistributedGridTest_1D, isBoundaryDomainTest )
{
   if( rank == 0 || rank == nproc - 1 )
      EXPECT_TRUE( distributedGrid->isBoundarySubdomain() );
   else
      EXPECT_FALSE( distributedGrid->isBoundarySubdomain() );
}

TEST_F(DistributedGridTest_1D, evaluateAllEntities)
{
   //Check Traversars
   //All entities, witout overlap
   setDof_1D( dof,-1);
   constFunctionEvaluator.evaluateAllEntities( meshFunctionPtr , constFunctionPtr );
   //Printer<GridType,DofType>::print_dof(rank,*gridptr,dof);
   check_Boundary_1D(rank, nproc, dof, rank);
   check_Overlap_1D(rank, nproc, dof, -1);
   check_Inner_1D(rank, nproc, dof, rank);
}

TEST_F(DistributedGridTest_1D, evaluateBoundaryEntities)
{
   //Boundary entities, witout overlap
   setDof_1D(dof,-1);
   constFunctionEvaluator.evaluateBoundaryEntities( meshFunctionPtr , constFunctionPtr );
   check_Boundary_1D(rank, nproc, dof, rank);
   check_Overlap_1D(rank, nproc, dof, -1);
   check_Inner_1D(rank, nproc, dof, -1);
}

TEST_F(DistributedGridTest_1D, evaluateInteriorEntities)
{
   //Inner entities, witout overlap
   setDof_1D(dof,-1);
   constFunctionEvaluator.evaluateInteriorEntities( meshFunctionPtr , constFunctionPtr );
   check_Boundary_1D(rank, nproc, dof, -1);
   check_Overlap_1D(rank, nproc, dof, -1);
   check_Inner_1D(rank, nproc, dof, rank);
}    

TEST_F(DistributedGridTest_1D, SynchronizerNeighborsTest )
{
   setDof_1D(dof,-1);
   constFunctionEvaluator.evaluateAllEntities( meshFunctionPtr , constFunctionPtr );
   meshFunctionPtr->template synchronize<CommunicatorType>();

   if(rank!=0)
      EXPECT_EQ((dof)[0],rank-1)<< "Left Overlap was filled by wrong process.";
   if(rank!=nproc-1)
      EXPECT_EQ((dof)[dof.getSize()-1],rank+1)<< "Right Overlap was filled by wrong process.";
}


TEST_F(DistributedGridTest_1D, LinearFunctionTest )
{
   //fill meshfunction with linear function (physical center of cell corresponds with its coordinates in grid) 
   setDof_1D(dof,-1);
   linearFunctionEvaluator.evaluateAllEntities(meshFunctionPtr, linearFunctionPtr);
   meshFunctionPtr->template synchronize<CommunicatorType>();

   auto entity = gridptr->template getEntity< Cell >(0);
   entity.refresh();
   EXPECT_EQ(meshFunctionPtr->getValue(entity), (*linearFunctionPtr)(entity)) << "Linear function Overlap error on left Edge.";

   auto entity2= gridptr->template getEntity< Cell >((dof).getSize()-1);
   entity2.refresh();
   EXPECT_EQ(meshFunctionPtr->getValue(entity), (*linearFunctionPtr)(entity)) << "Linear function Overlap error on right Edge.";
}


TEST_F(DistributedGridTest_1D, SynchronizePeriodicNeighborsTest )
{
   // Setup periodic boundaries
   // TODO: I do not know how to do it better with GTEST
   typename DistributedGridType::SubdomainOverlapsType lowerOverlap, upperOverlap;
   SubdomainOverlapsGetter< GridType, CommunicatorType >::
      getOverlaps( distributedGrid, lowerOverlap, upperOverlap, 1, 1 );
   distributedGrid->setOverlaps( lowerOverlap, upperOverlap );
   distributedGrid->setupGrid(*gridptr);
   dof.setSize( gridptr->template getEntitiesCount< Cell >() );
   meshFunctionPtr->bind( gridptr, dof );

   setDof_1D( dof, -rank-1 );
   constFunctionEvaluator.evaluateAllEntities( meshFunctionPtr , constFunctionPtr );
   meshFunctionPtr->template synchronize<CommunicatorType>( true );

   if( rank == 0 )
      EXPECT_EQ( dof[ 1 ], -nproc ) << "Left Overlap was filled by wrong process.";
   if( rank == nproc-1 )
      EXPECT_EQ( dof[ dof.getSize() - 2 ], -1 )<< "Right Overlap was filled by wrong process.";
}

TEST_F(DistributedGridTest_1D, SynchronizePeriodicBoundariesLinearTest )
{
   // Setup periodic boundaries
   // TODO: I do not know how to do it better with GTEST - additional setup 
   // of the periodic boundaries
   typename DistributedGridType::SubdomainOverlapsType lowerOverlap, upperOverlap;
   SubdomainOverlapsGetter< GridType, CommunicatorType >::
      getOverlaps( distributedGrid, lowerOverlap, upperOverlap, 1, 1 );
   distributedGrid->setOverlaps( lowerOverlap, upperOverlap );
   distributedGrid->setupGrid(*gridptr);
   dof.setSize( gridptr->template getEntitiesCount< Cell >() );
   meshFunctionPtr->bind( gridptr, dof );

   setDof_1D(dof, -rank-1 );
   linearFunctionEvaluator.evaluateAllEntities( meshFunctionPtr , linearFunctionPtr );
   
   //TNL_MPI_PRINT( meshFunctionPtr->getData() );
   
   meshFunctionPtr->template synchronize<CommunicatorType>( true );
   
   //TNL_MPI_PRINT( meshFunctionPtr->getData() );
   
   auto entity = gridptr->template getEntity< Cell >( 1 );
   auto entity2= gridptr->template getEntity< Cell >( (dof).getSize() - 2 );
   entity.refresh();
   entity2.refresh();   
   
   if( rank == 0 )
      EXPECT_EQ( meshFunctionPtr->getValue(entity), -nproc ) << "Linear function Overlap error on left Edge.";
   if( rank == nproc - 1 )
      EXPECT_EQ( meshFunctionPtr->getValue(entity2), -1 ) << "Linear function Overlap error on right Edge.";
}



#else
TEST(NoMPI, NoTest)
{
    ASSERT_TRUE(true) << ":-(";
}
#endif

#endif


#if (defined(HAVE_GTEST) && defined(HAVE_MPI))
#include <sstream>

  class MinimalistBufferedPrinter : public ::testing::EmptyTestEventListener {
      
  private:
      std::stringstream sout;
      
  public:
      
    // Called before a test starts.
    virtual void OnTestStart(const ::testing::TestInfo& test_info) {
      sout<< test_info.test_case_name() <<"." << test_info.name() << " Start." <<std::endl;
    }

    // Called after a failed assertion or a SUCCEED() invocation.
    virtual void OnTestPartResult(
        const ::testing::TestPartResult& test_part_result) {
      sout << (test_part_result.failed() ? "====Failure=== " : "===Success=== ") 
              << test_part_result.file_name() << " "
              << test_part_result.line_number() <<std::endl
              << test_part_result.summary() <<std::endl;
    }

    // Called after a test ends.
    virtual void OnTestEnd(const ::testing::TestInfo& test_info) 
    {
		int rank=CommunicatorType::GetRank(CommunicatorType::AllGroup);
        sout<< test_info.test_case_name() <<"." << test_info.name() << " End." <<std::endl;
        std::cout << rank << ":" << std::endl << sout.str()<< std::endl;
        sout.str( std::string() );
        sout.clear();
    }
  };
#endif

#include "../../src/UnitTests/GtestMissingError.h"
int main( int argc, char* argv[] )
{
#ifdef HAVE_GTEST
   ::testing::InitGoogleTest( &argc, argv );

    #ifdef HAVE_MPI
       ::testing::TestEventListeners& listeners =
          ::testing::UnitTest::GetInstance()->listeners();

       delete listeners.Release(listeners.default_result_printer());
       listeners.Append(new MinimalistBufferedPrinter);

       CommunicatorType::Init(argc,argv);
    #endif
       int result= RUN_ALL_TESTS();

    #ifdef HAVE_MPI
       CommunicatorType::Finalize();
    #endif
       return result;
#else
   
   throw GtestMissingError();
#endif
}