//======================================================================================================================
//
//  This file is part of waLBerla. waLBerla is free software: you can 
//  redistribute it and/or modify it under the terms of the GNU General Public
//  License as published by the Free Software Foundation, either version 3 of 
//  the License, or (at your option) any later version.
//  
//  waLBerla is distributed in the hope that it will be useful, but WITHOUT 
//  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
//  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License 
//  for more details.
//  
//  You should have received a copy of the GNU General Public License along
//  with waLBerla (see COPYING.txt). If not, see <http://www.gnu.org/licenses/>.
//
//! \file BufferTest.cpp
//! \ingroup core
//! \author Martin Bauer <martin.bauer@fau.de>
//! \brief Simple read and write testing of SendBuffer and RecvBuffer
//!
//! This test case writes values of different types to a SendBuffer
//! then simulates the communication with a memcpy and finally
//! extracts the values from the RecvBuffer and compares them
//
//======================================================================================================================

#include "core/DataTypes.h"
#include "core/cell/Cell.h"
#include "core/cell/CellInterval.h"
#include "core/cell/CellSet.h"
#include "core/cell/CellVector.h"
#include "core/debug/TestSubsystem.h"
#include "core/math/Matrix3.h"
#include "core/math/Vector3.h"
#include "core/mpi/BufferDataTypeExtensions.h"
#include "core/mpi/RecvBuffer.h"
#include "core/mpi/SendBuffer.h"

#include <random>
#include <cstring>
#include <iostream>


using namespace walberla;
using namespace mpi;

template<typename T>
void initIntegerContainer( T & container )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<typename T::value_type> dist;
   std::uniform_int_distribution<size_t> size_dist(10,1000);

   size_t size = size_dist(rng);
   container.clear();
   for(size_t i = 0; i < size; ++i )
      container.push_back( dist(rng) );
}

template<typename T>
void initIntegerAssocContainer( T & container )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<typename T::value_type> dist;
   std::uniform_int_distribution<size_t> size_dist(10,1000);

   size_t size = size_dist(rng);
   container.clear();
   for(size_t i = 0; i < size; ++i )
      container.insert( container.end(), dist(rng) );
}


void initVecBool( std::vector<bool> & vecBool )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<walberla::uint32_t> dist;
   std::uniform_int_distribution<size_t> size_dist(10,1000);

   size_t size = size_dist(rng);
   vecBool.clear();
   for(size_t i = 0; i < size; ++i )
      vecBool.push_back( dist(rng) % 2 != 0);
}


template<typename T>
void initIntegerMap( T & container )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<typename T::mapped_type> mapped_dist;
   std::uniform_int_distribution<typename T::key_type> key_dist;
   std::uniform_int_distribution<size_t> size_dist(10,1000);

   size_t size = size_dist(rng);
   container.clear();
   for(size_t i = 0; i < size; ++i )
      container.insert( container.end(), std::make_pair(key_dist(rng), mapped_dist(rng)) );
}


template<typename T>
void initCellContainer( T & container )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<cell_idx_t> dist;
   std::uniform_int_distribution<size_t> size_dist(10,1000);

   size_t size = size_dist(rng);
   container.clear();
   for(size_t i = 0; i < size; ++i )
      container.insert( container.end(), Cell( dist(rng), dist(rng), dist(rng) ) );
}

template<typename T, std::size_t N>
void initBoostArray( boost::array< T, N > & array )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<T> dist;

   for( auto it = array.begin(); it != array.end(); ++it )
      *it = dist( rng );
}

template<typename T, std::size_t N>
void initStdArray( std::array< T, N > & array )
{
   static std::mt19937 rng;
   std::uniform_int_distribution<T> dist;

   for( auto it = array.begin(); it != array.end(); ++it )
      *it = dist( rng );
}


/// Simulates one send and receive operation
/// data is put into send buffer and copied to RecvBuffer
/// Then the values are compared to sent values
template<typename T>
void bufferTest()
{
   const double          testDouble = 42.242;
   const int             testInt = 10;
   const Vector3<int>    vec(1,2,3);
   const Matrix3<double> mat(1,2,3,4,5,6,7,8,9);
   const Cell            cell(1,2,3);
   const CellInterval    cellInterval( Cell(1,2,3), Cell(4,5,6) );

   CellVector            cellVector;
   CellSet               cellSet;

   initCellContainer(cellVector);
   initCellContainer(cellSet);

   std::vector  <bool>         boolStdVec,  boolStdVecEmpty;
   std::vector  <unsigned int> stdVec,      stdVecEmpty;
   std::deque   <unsigned int> stdDeque,    stdDequeEmpty;
   std::list    <unsigned int> stdList,     stdListEmpty;
   std::set     <unsigned int> stdSet,      stdSetEmpty;
   std::multiset<unsigned int> stdMultiSet, stdMultiSetEmpty;

   std::map     <unsigned int, walberla::int64_t> stdMap,      stdMapEmpty;
   std::multimap<unsigned int, walberla::int64_t> stdMultiMap, stdMultiMapEmpty;

   boost::array< unsigned int, 19 > boostArray;
   std::array  < unsigned int, 19 > stdArray;

   initVecBool(boolStdVec);
   initIntegerContainer(stdVec);
   initIntegerContainer(stdDeque);
   initIntegerContainer(stdList);
   initIntegerAssocContainer(stdSet);
   initIntegerAssocContainer(stdMultiSet);
   initIntegerMap(stdMap);
   initIntegerMap(stdMultiMap);
   initBoostArray(boostArray);
   initStdArray(stdArray);

   // Create send buffer and put two values in it
   GenericSendBuffer<T> sb;
   sb << testDouble  << testInt;
   sb << vec         << mat;
   sb << cell        << cellInterval;
   sb << cellVector  << cellSet;
   sb << boolStdVec  << boolStdVecEmpty;
   sb << stdVec      << stdVecEmpty;
   sb << stdDeque    << stdDequeEmpty;
   sb << stdList     << stdListEmpty;
   sb << stdSet      << stdSetEmpty;
   sb << stdMultiSet << stdMultiSetEmpty;
   sb << stdMap      << stdMapEmpty;
   sb << stdMultiMap << stdMultiMapEmpty;
   sb << boostArray  << stdArray;

   // Copying
   //RecvBuffer<T> rb;
   //rb.resize( sb.size() );
   //memcpy(rb.ptr(),sb.ptr(), sb.size()* sizeof(T));

   // Transferring data to receive buffer
   GenericRecvBuffer<T> rb( sb );

   // Extracting Values
   double          recvD;
   int             recvI;
   Vector3<int>    recvVec;
   Matrix3<double> recvMat;
   Cell            recvCell;
   CellInterval    recvCellInterval;
   CellVector      recvCellVector;
   CellSet         recvCellSet;

   std::vector  <bool>         recvBoolStdVec,  recvBoolStdVecEmpty;
   std::vector  <unsigned int> recvStdVec,      recvStdVecEmpty;
   std::deque   <unsigned int> recvStdDeque,    recvStdDequeEmpty;
   std::list    <unsigned int> recvStdList,     recvStdListEmpty;
   std::set     <unsigned int> recvStdSet,      recvStdSetEmpty;
   std::multiset<unsigned int> recvStdMultiSet, recvStdMultiSetEmpty;

   std::map     <unsigned int, walberla::int64_t> recvStdMap,      recvStdMapEmpty;
   std::multimap<unsigned int, walberla::int64_t> recvStdMultiMap, recvStdMultiMapEmpty;

   boost::array<unsigned int, 19> recvBoostArray;
   std::array  <unsigned int, 19> recvStdArray;

   rb >> recvD           >> recvI;
   rb >> recvVec         >> recvMat;
   rb >> recvCell        >> recvCellInterval;
   rb >> recvCellVector  >> recvCellSet;
   rb >> recvBoolStdVec  >> recvBoolStdVecEmpty;
   rb >> recvStdVec      >> recvStdVecEmpty;
   rb >> recvStdDeque    >> recvStdDequeEmpty;
   rb >> recvStdList     >> recvStdListEmpty;
   rb >> recvStdSet      >> recvStdSetEmpty;
   rb >> recvStdMultiSet >> recvStdMultiSetEmpty;
   rb >> recvStdMap      >> recvStdMapEmpty;
   rb >> recvStdMultiMap >> recvStdMultiMapEmpty;
   rb >> recvBoostArray  >> recvStdArray;

   // Validate
   WALBERLA_CHECK_FLOAT_EQUAL(recvD,testDouble);

   WALBERLA_CHECK_EQUAL(recvI,    testInt);
   WALBERLA_CHECK_EQUAL(recvVec,  vec);
   WALBERLA_CHECK_EQUAL(recvMat,  mat);
   WALBERLA_CHECK_EQUAL(recvCell, cell);
   WALBERLA_CHECK_EQUAL(recvCellInterval, cellInterval);
   WALBERLA_CHECK_EQUAL(recvCellVector,   cellVector);
   WALBERLA_CHECK(recvCellSet == cellSet);

   WALBERLA_CHECK_EQUAL(recvBoolStdVec,      boolStdVec);
   WALBERLA_CHECK_EQUAL(recvBoolStdVecEmpty, boolStdVecEmpty);
   WALBERLA_CHECK_EQUAL(recvStdVec,          stdVec);
   WALBERLA_CHECK_EQUAL(recvStdVecEmpty,     stdVecEmpty);
   WALBERLA_CHECK_EQUAL(recvStdDeque,        stdDeque);
   WALBERLA_CHECK_EQUAL(recvStdDequeEmpty,   stdDequeEmpty);
   WALBERLA_CHECK_EQUAL(recvStdList,         stdList);
   WALBERLA_CHECK_EQUAL(recvStdListEmpty,    stdListEmpty);

   WALBERLA_CHECK_EQUAL(recvStdSet,           stdSet);
   WALBERLA_CHECK_EQUAL(recvStdSetEmpty,      stdSetEmpty);
   WALBERLA_CHECK_EQUAL(recvStdMultiSet,      stdMultiSet);
   WALBERLA_CHECK_EQUAL(recvStdMultiSetEmpty, stdMultiSetEmpty);
   WALBERLA_CHECK_EQUAL(recvStdMap,           stdMap);
   WALBERLA_CHECK_EQUAL(recvStdMapEmpty,      stdMapEmpty);
   WALBERLA_CHECK_EQUAL(recvStdMultiMap,      stdMultiMap);
   WALBERLA_CHECK_EQUAL(recvStdMultiMapEmpty, stdMultiMapEmpty);

   WALBERLA_CHECK_EQUAL(recvBoostArray, boostArray);
   WALBERLA_CHECK_EQUAL(recvStdArray,   stdArray);
}


// Special test function to check serializations that only work with buffers that utilize
// uint8_t as underlying data type
void bufferTestUInt8()
{
   std::string stdString("Hello World!"), stdStringEmpty;

   walberla::optional<int> optional0, optional1, optional2, optional3;
   optional2 = 23;
   optional3 = 42;

   // Create send buffer and put two values in it
   GenericSendBuffer<walberla::uint8_t> sb;
   sb << stdString << stdStringEmpty;
   sb << optional0 << optional1 << optional2 << optional3;

   // Copying
   GenericRecvBuffer<walberla::uint8_t> rb( sb );

   std::string recvStdString, recvStdStringEmpty;

   walberla::optional<int> recvOptional0, recvOptional1, recvOptional2, recvOptional3;

   recvOptional0 = 123;
   recvOptional1 = 123;
   recvOptional2 = 456;
   recvOptional3 = 456;

   rb >> recvStdString >> recvStdStringEmpty;
   rb >> recvOptional0 >> recvOptional1;
   rb >> recvOptional2 >> recvOptional3;

   WALBERLA_CHECK_EQUAL(recvStdString,       stdString);
   WALBERLA_CHECK_EQUAL(recvStdStringEmpty,  stdStringEmpty);

   WALBERLA_CHECK( optional0 == recvOptional0 );
   WALBERLA_CHECK( optional1 == recvOptional1 );
   WALBERLA_CHECK( optional2 == recvOptional2 );
   WALBERLA_CHECK( optional3 == recvOptional3 );
}


void bufferOverwriteTest()
{
   //! [SendBuffer Overwrite Test]
   int a = 1;
   int b = 2;
   int c = 3;
   SendBuffer sb;
   auto ptr = sb.allocate<int>(2);
   sb << b << c;
   *ptr   = a;
   ptr[1] = c;
   //ptr[2] = c; // will fail in debug: out of bounds
   //! [SendBuffer Overwrite Test]

   // Copying
   RecvBuffer rb( sb );

   int recv;

   rb >> recv;
   WALBERLA_CHECK_EQUAL(a, recv);
   rb >> recv;
   WALBERLA_CHECK_EQUAL(c, recv);
   rb >> recv;
   WALBERLA_CHECK_EQUAL(b, recv);
   rb >> recv;
   WALBERLA_CHECK_EQUAL(c, recv);
}


int main()
{
   debug::enterTestMode();

   bufferTest<unsigned char>() ;
   bufferTest<unsigned short>();
   bufferTest<unsigned int>()  ;

   bufferTestUInt8();

   // This should not compile, since the containing type has be be smaller
   // than the type that is stored
   //bufferTest<double>();

   bufferOverwriteTest();

   return 0;
}