source: XIOS/trunk/src/node/field.cpp @ 1326

#include "field.hpp"

#include "attribute_template.hpp"
#include "object_template.hpp"
#include "group_template.hpp"

#include "node_type.hpp"
#include "calendar_util.hpp"
#include "message.hpp"
#include "xios_spl.hpp"
#include "type.hpp"
#include "timer.hpp"
#include "context_client.hpp"
#include "context_server.hpp"
#include <set>
#include "garbage_collector.hpp"
#include "source_filter.hpp"
#include "store_filter.hpp"
#include "file_writer_filter.hpp"
#include "pass_through_filter.hpp"
#include "filter_expr_node.hpp"
#include "lex_parser.hpp"
#include "temporal_filter.hpp"
#include "spatial_transform_filter.hpp"

namespace xios{

   /// ////////////////////// Définitions ////////////////////// ///

   CField::CField(void)
      : CObjectTemplate<CField>(), CFieldAttributes()
      , grid(), file()
      , written(false)
      , nstep(0), nstepMax(0)
      , hasOutputFile(false)
      , domAxisScalarIds_(vector<StdString>(3,"")), areAllReferenceSolved(false), isReferenceSolved(false)
      , useCompressedOutput(false)
      , hasTimeInstant(false)
      , hasTimeCentered(false)
      , wasDataRequestedFromServer(false)
      , wasDataAlreadyReceivedFromServer(false)
      , isEOF(false)
   { setVirtualVariableGroup(CVariableGroup::create(getId() + "_virtual_variable_group")); }

   CField::CField(const StdString& id)
      : CObjectTemplate<CField>(id), CFieldAttributes()
      , grid(), file()
      , written(false)
      , nstep(0), nstepMax(0)
      , hasOutputFile(false)
      , domAxisScalarIds_(vector<StdString>(3,"")), areAllReferenceSolved(false), isReferenceSolved(false)
      , useCompressedOutput(false)
      , hasTimeInstant(false)
      , hasTimeCentered(false)
      , wasDataRequestedFromServer(false)
      , wasDataAlreadyReceivedFromServer(false)
      , isEOF(false)
   { setVirtualVariableGroup(CVariableGroup::create(getId() + "_virtual_variable_group")); }

   CField::~CField(void)
   {}

  //----------------------------------------------------------------

   void CField::setVirtualVariableGroup(CVariableGroup* newVVariableGroup)
   {
      this->vVariableGroup = newVVariableGroup;
   }

   CVariableGroup* CField::getVirtualVariableGroup(void) const
   {
      return this->vVariableGroup;
   }

   std::vector<CVariable*> CField::getAllVariables(void) const
   {
      return this->vVariableGroup->getAllChildren();
   }

   void CField::solveDescInheritance(bool apply, const CAttributeMap* const parent)
   {
      SuperClassAttribute::setAttributes(parent, apply);
      this->getVirtualVariableGroup()->solveDescInheritance(apply, NULL);
   }

  //----------------------------------------------------------------

  bool CField::dispatchEvent(CEventServer& event)
  {
    if (SuperClass::dispatchEvent(event)) return true;
    else
    {
      switch(event.type)
      {
        case EVENT_ID_UPDATE_DATA :
          recvUpdateData(event);
          return true;
          break;

        case EVENT_ID_READ_DATA :
          recvReadDataRequest(event);
          return true;
          break;

        case EVENT_ID_READ_DATA_READY :
          recvReadDataReady(event);
          return true;
          break;

        case EVENT_ID_ADD_VARIABLE :
          recvAddVariable(event);
          return true;
          break;

        case EVENT_ID_ADD_VARIABLE_GROUP :
          recvAddVariableGroup(event);
          return true;
          break;

        default :
          ERROR("bool CField::dispatchEvent(CEventServer& event)", << "Unknown Event");
          return false;
      }
    }
  }

  void CField::sendUpdateData(const CArray<double,1>& data)
  {
    CTimer::get("Field : send data").resume();

    CContext* context = CContext::getCurrent();
    CContextClient* client = context->client;

    CEventClient event(getType(), EVENT_ID_UPDATE_DATA);

    map<int, CArray<int,1> >::iterator it;
    list<CMessage> list_msg;
    list<CArray<double,1> > list_data;

    if (!grid->doGridHaveDataDistributed())
    {
       if (client->isServerLeader())
       {
          for (it = grid->storeIndex_toSrv.begin(); it != grid->storeIndex_toSrv.end(); it++)
          {
            int rank = it->first;
            CArray<int,1>& index = it->second;

            list_msg.push_back(CMessage());
            list_data.push_back(CArray<double,1>(index.numElements()));

            CArray<double,1>& data_tmp = list_data.back();
            for (int n = 0; n < data_tmp.numElements(); n++) data_tmp(n) = data(index(n));

            list_msg.back() << getId() << data_tmp;
            event.push(rank, 1, list_msg.back());
          }
          client->sendEvent(event);
       } 
       else client->sendEvent(event);
    }
    else
    {
      for (it = grid->storeIndex_toSrv.begin(); it != grid->storeIndex_toSrv.end(); it++)
      {
        int rank = it->first;
        CArray<int,1>& index = it->second;

        list_msg.push_back(CMessage());
        list_data.push_back(CArray<double,1>(index.numElements()));

        CArray<double,1>& data_tmp = list_data.back();
        for (int n = 0; n < data_tmp.numElements(); n++) data_tmp(n) = data(index(n));

        list_msg.back() << getId() << data_tmp;
        event.push(rank, grid->nbSenders[rank], list_msg.back());
      }
      client->sendEvent(event);
    }

    CTimer::get("Field : send data").suspend();
  }

  void CField::recvUpdateData(CEventServer& event)
  {
    vector<int> ranks;
    vector<CBufferIn*> buffers;

    list<CEventServer::SSubEvent>::iterator it;
    string fieldId;
    CTimer::get("Field : recv data").resume();
    for (it = event.subEvents.begin(); it != event.subEvents.end(); ++it)
    {
      int rank = it->rank;
      CBufferIn* buffer = it->buffer;
      *buffer >> fieldId;
      ranks.push_back(rank);
      buffers.push_back(buffer);
    }
    get(fieldId)->recvUpdateData(ranks,buffers);
    CTimer::get("Field : recv data").suspend();
  }

  void  CField::recvUpdateData(vector<int>& ranks, vector<CBufferIn*>& buffers)
  {
    if (data_srv.empty())
    {
      for (map<int, CArray<size_t, 1> >::iterator it = grid->outIndexFromClient.begin(); it != grid->outIndexFromClient.end(); ++it)
      {
        int rank = it->first;
        data_srv.insert(std::make_pair(rank, CArray<double,1>(it->second.numElements())));
        foperation_srv.insert(pair<int,boost::shared_ptr<func::CFunctor> >(rank,boost::shared_ptr<func::CFunctor>(new func::CInstant(data_srv[rank]))));
      }
    }

    CContext* context = CContext::getCurrent();
    const CDate& currDate = context->getCalendar()->getCurrentDate();
    const CDate opeDate      = last_operation_srv +freq_op + freq_operation_srv - freq_op;
    const CDate writeDate    = last_Write_srv     + freq_write_srv;

    if (opeDate <= currDate)
    {
      for (int n = 0; n < ranks.size(); n++)
      {
        CArray<double,1> data_tmp;
        *buffers[n] >> data_tmp;
        (*foperation_srv[ranks[n]])(data_tmp);
      }
      last_operation_srv = currDate;
    }

    if (writeDate < (currDate + freq_operation_srv))
    {
      for (int n = 0; n < ranks.size(); n++)
      {
        this->foperation_srv[ranks[n]]->final();
      }

      last_Write_srv = writeDate;
      writeField();
      lastlast_Write_srv = last_Write_srv;
    }
  }

  void CField::writeField(void)
  {
    if (!getRelFile()->allDomainEmpty)
    {
      if (grid->doGridHaveDataToWrite() || getRelFile()->type == CFile::type_attr::one_file)
      {
        getRelFile()->checkFile();
        this->incrementNStep();
        getRelFile()->getDataOutput()->writeFieldData(CField::get(this));
      }
    }
  }

  bool CField::sendReadDataRequest(const CDate& tsDataRequested)
  {
    CContext* context = CContext::getCurrent();
    CContextClient* client = context->client;

    lastDataRequestedFromServer = tsDataRequested;

    // No need to send the request if we are sure that we are already at EOF
    if (!isEOF || context->getCalendar()->getCurrentDate() <= dateEOF)
    {
      CEventClient event(getType(), EVENT_ID_READ_DATA);
      if (client->isServerLeader())
      {
        CMessage msg;
        msg << getId();
        const std::list<int>& ranks = client->getRanksServerLeader();
        for (std::list<int>::const_iterator itRank = ranks.begin(), itRankEnd = ranks.end(); itRank != itRankEnd; ++itRank)
          event.push(*itRank, 1, msg);
        client->sendEvent(event);
      }
      else client->sendEvent(event);
    }
    else
      serverSourceFilter->signalEndOfStream(tsDataRequested);

    wasDataRequestedFromServer = true;

    return !isEOF;
  }

  /*!
  Send request new data read from file if need be, that is the current data is out-of-date.
  \return true if and only if some data was requested
  */
  bool CField::sendReadDataRequestIfNeeded(void)
  {
    const CDate& currentDate = CContext::getCurrent()->getCalendar()->getCurrentDate();

    bool dataRequested = false;

    while (currentDate >= lastDataRequestedFromServer)
    {
      info(20) << "currentDate : " << currentDate << endl ;
      info(20) << "lastDataRequestedFromServer : " << lastDataRequestedFromServer << endl ;
      info(20) << "file->output_freq.getValue() : " << file->output_freq.getValue() << endl ;
      info(20) << "lastDataRequestedFromServer + file->output_freq.getValue() : " << lastDataRequestedFromServer + file->output_freq << endl ;

      dataRequested |= sendReadDataRequest(lastDataRequestedFromServer + file->output_freq);
    }

    return dataRequested;
  }

  void CField::recvReadDataRequest(CEventServer& event)
  {
    CBufferIn* buffer = event.subEvents.begin()->buffer;
    StdString fieldId;
    *buffer >> fieldId;
    get(fieldId)->recvReadDataRequest();
  }

  void CField::recvReadDataRequest(void)
  {
    CContext* context = CContext::getCurrent();
    CContextClient* client = context->client;

    CEventClient event(getType(), EVENT_ID_READ_DATA_READY);
    std::list<CMessage> msgs;

    bool hasData = readField();

    map<int, CArray<double,1> >::iterator it;
    if (!grid->doGridHaveDataDistributed())
    {
       if (client->isServerLeader())
       {
          if (!data_srv.empty())
          {
            it = data_srv.begin();
            const std::list<int>& ranks = client->getRanksServerLeader();
            for (std::list<int>::const_iterator itRank = ranks.begin(), itRankEnd = ranks.end(); itRank != itRankEnd; ++itRank)
            {
              msgs.push_back(CMessage());
              CMessage& msg = msgs.back();
              msg << getId();
              if (hasData)
                msg << getNStep() - 1 << it->second;
              else
                msg << int(-1);
              event.push(*itRank, 1, msg);
            }
          }
          client->sendEvent(event);
       } 
       else 
       {
          // if (!data_srv.empty())
          // {
          //   it = data_srv.begin();
          //   const std::list<int>& ranks = client->getRanksServerNotLeader();
          //   for (std::list<int>::const_iterator itRank = ranks.begin(), itRankEnd = ranks.end(); itRank != itRankEnd; ++itRank)
          //   {
          //     msgs.push_back(CMessage());
          //     CMessage& msg = msgs.back();
          //     msg << getId();
          //     if (hasData)
          //       msg << getNStep() - 1 << it->second;
          //     else
          //       msg << int(-1);
          //     event.push(*itRank, 1, msg);
          //   }
          // }
          client->sendEvent(event);
       }
    }
    else
    {
      for (it = data_srv.begin(); it != data_srv.end(); it++)
      {
        msgs.push_back(CMessage());
        CMessage& msg = msgs.back();
        msg << getId();
        if (hasData)
          msg << getNStep() - 1 << it->second;
        else
          msg << int(-1);
        event.push(it->first, grid->nbSenders[it->first], msg);
      }
      client->sendEvent(event);
    }
  }

  bool CField::readField(void)
  {
    if (!getRelFile()->allDomainEmpty)
    {
      if (grid->doGridHaveDataToWrite() || getRelFile()->type == CFile::type_attr::one_file)
      {
        if (data_srv.empty())
        {
          for (map<int, CArray<size_t, 1> >::iterator it = grid->outIndexFromClient.begin(); it != grid->outIndexFromClient.end(); ++it)
            data_srv.insert(std::make_pair(it->first, CArray<double,1>(it->second.numElements())));
        }

        getRelFile()->checkFile();
        if (!nstepMax)
        {
          nstepMax = getRelFile()->getDataInput()->getFieldNbRecords(CField::get(this));
        }

        this->incrementNStep();

        if (getNStep() > nstepMax && (getRelFile()->cyclic.isEmpty() || !getRelFile()->cyclic) )
          return false;

        getRelFile()->getDataInput()->readFieldData(CField::get(this));
      }
    }

    return true;
  }

  void CField::recvReadDataReady(CEventServer& event)
  {
    string fieldId;
    vector<int> ranks;
    vector<CBufferIn*> buffers;

    list<CEventServer::SSubEvent>::iterator it;
    for (it = event.subEvents.begin(); it != event.subEvents.end(); ++it)
    {
      ranks.push_back(it->rank);
      CBufferIn* buffer = it->buffer;
      *buffer >> fieldId;
      buffers.push_back(buffer);
    }
    get(fieldId)->recvReadDataReady(ranks, buffers);
  }

  void CField::recvReadDataReady(vector<int> ranks, vector<CBufferIn*> buffers)
  {
    CContext* context = CContext::getCurrent();
    std::map<int, CArray<double,1> > data;
    const bool wasEOF = isEOF;

    for (int i = 0; i < ranks.size(); i++)
    {
      int rank = ranks[i];
      int record;
      *buffers[i] >> record;
      isEOF = (record == int(-1));

      if (!isEOF)
        *buffers[i] >> data[rank];
      else
        break;
    }

    if (wasDataAlreadyReceivedFromServer)
      lastDataReceivedFromServer = lastDataReceivedFromServer + file->output_freq;
    else
    {
      lastDataReceivedFromServer = context->getCalendar()->getInitDate();
      wasDataAlreadyReceivedFromServer = true;
    }

    if (isEOF)
    {
      if (!wasEOF)
        dateEOF = lastDataReceivedFromServer;

      serverSourceFilter->signalEndOfStream(lastDataReceivedFromServer);
    }
    else
      serverSourceFilter->streamDataFromServer(lastDataReceivedFromServer, data);
  }

  void CField::checkForLateDataFromServer(void)
  {
    CContext* context = CContext::getCurrent();
    const CDate& currentDate = context->getCalendar()->getCurrentDate();

    // Check if data previously requested has been received as expected
    if (wasDataRequestedFromServer && (!isEOF || currentDate <= dateEOF))
    {
      CTimer timer("CField::checkForLateDataFromServer");

      bool isDataLate;
      do
      {
        const CDate nextDataDue = wasDataAlreadyReceivedFromServer ? (lastDataReceivedFromServer + file->output_freq) : context->getCalendar()->getInitDate();
        isDataLate = nextDataDue < currentDate;

        if (isDataLate)
        {
          timer.resume();

          context->checkBuffersAndListen();

          timer.suspend();
        }
      }
      while (isDataLate && timer.getCumulatedTime() < CXios::recvFieldTimeout);

      if (isDataLate)
        ERROR("void CField::checkForLateDataFromServer(void)",
              << "Late data at timestep = " << currentDate);
    }
  }

   //----------------------------------------------------------------

   void CField::setRelFile(CFile* _file)
   {
      this->file = _file;
      hasOutputFile = true;
   }

   //----------------------------------------------------------------

   StdString CField::GetName(void)    { return StdString("field"); }
   StdString CField::GetDefName(void) { return CField::GetName(); }
   ENodeType CField::GetType(void)    { return eField; }

   //----------------------------------------------------------------

   CGrid* CField::getRelGrid(void) const
   {
      return this->grid;
   }

   //----------------------------------------------------------------

   CFile* CField::getRelFile(void) const
   {
      return this->file;
   }

   int CField::getNStep(void) const
   {
      return this->nstep;
   }

   func::CFunctor::ETimeType CField::getOperationTimeType() const
   {
     return operationTimeType;
   }

   //----------------------------------------------------------------

   void CField::incrementNStep(void)
   {
      this->nstep++;
   }

   void CField::resetNStep(int nstep /*= 0*/)
   {
      this->nstep = nstep;
   }

   void CField::resetNStepMax(void)
   {
      this->nstepMax = 0;
   }

   //----------------------------------------------------------------

   bool CField::isActive(bool atCurrentTimestep /*= false*/) const
   {
      if (clientSourceFilter)
        return atCurrentTimestep ? clientSourceFilter->isDataExpected(CContext::getCurrent()->getCalendar()->getCurrentDate()) : true;
      else if (storeFilter)
        return true;
      else if (instantDataFilter)
        ERROR("bool CField::isActive(bool atCurrentTimestep)",
              << "Impossible to check if field [ id = " << getId() << " ] is active as it cannot be used to receive nor send data.");

      return false;
   }

   //----------------------------------------------------------------

   bool CField::wasWritten() const
   {
     return written;
   }

   void CField::setWritten()
   {
     written = true;
   }

   //----------------------------------------------------------------

   bool CField::getUseCompressedOutput() const
   {
     return useCompressedOutput;
   }

   void CField::setUseCompressedOutput()
   {
     useCompressedOutput = true;
   }

   //----------------------------------------------------------------

   boost::shared_ptr<COutputPin> CField::getInstantDataFilter()
   {
     return instantDataFilter;
   }

   //----------------------------------------------------------------

   void CField::solveOnlyReferenceEnabledField(bool doSending2Server)
   {
     CContext* context = CContext::getCurrent();
     if (!isReferenceSolved)
     {
        isReferenceSolved = true;

        if (context->hasClient)
        {
          solveRefInheritance(true);
          if (hasDirectFieldReference()) getDirectFieldReference()->solveOnlyReferenceEnabledField(false);
        }
        else if (context->hasServer)
          solveServerOperation();

        solveGridReference();

       if (context->hasClient)
       {
         solveGenerateGrid();
         buildGridTransformationGraph();
       }
     }
   }

   /*!
     Build up graph of grids which plays role of destination and source in grid transformation
     This function should be called before \func solveGridReference()
   */
   void CField::buildGridTransformationGraph()
   {
     CContext* context = CContext::getCurrent();
     if (context->hasClient)
     {
       if (grid && !grid->isTransformed() && hasDirectFieldReference() && grid != getDirectFieldReference()->grid)
       {
         grid->addTransGridSource(getDirectFieldReference()->grid);
       }
     }
   }

   /*!
     Generate a new grid destination if there are more than one grid source pointing to a same grid destination
   */
   void CField::generateNewTransformationGridDest()
   {
     CContext* context = CContext::getCurrent();
     if (context->hasClient)
     {
       std::map<CGrid*,std::pair<bool,StdString> >& gridSrcMap = grid->getTransGridSource();
       if (1 < gridSrcMap.size())
       {
         // Search for grid source
         CGrid* gridSrc = grid;
         CField* currField = this;
         std::vector<CField*> hieraField;

         while (currField->hasDirectFieldReference() && (gridSrc == grid))
         {
           hieraField.push_back(currField);
           CField* tmp = currField->getDirectFieldReference();
           currField = tmp;
           gridSrc = currField->grid;
         }

         if (gridSrcMap.end() != gridSrcMap.find(gridSrc))
         {
           CGrid* gridTmp;
           std::pair<bool,StdString> newGridDest = gridSrcMap[gridSrc];
           if (newGridDest.first)
           {
             StdString newIdGridDest = newGridDest.second;
             if (!CGrid::has(newIdGridDest))
             {
                ERROR("CGrid* CGrid::generateNewTransformationGridDest()",
                  << " Something wrong happened! Grid whose id " << newIdGridDest
                  << "should exist ");
             }
             gridTmp = CGrid::get(newIdGridDest);
           }
           else
           {
             StdString newIdGridDest = CGrid::generateId(gridSrc, grid);
             gridTmp = CGrid::cloneGrid(newIdGridDest, grid);

             (gridSrcMap[gridSrc]).first = true;
             (gridSrcMap[gridSrc]).second = newIdGridDest;
           }

           // Update all descendants
           for (std::vector<CField*>::iterator it = hieraField.begin(); it != hieraField.end(); ++it)
           {
             (*it)->grid = gridTmp;
             (*it)->updateRef((*it)->grid);
           }
         }
       }
     }
   }

   void CField::updateRef(CGrid* grid)
   {
     if (!grid_ref.isEmpty()) grid_ref.setValue(grid->getId());
     else
     {
       std::vector<CAxis*> axisTmp = grid->getAxis();
       std::vector<CDomain*> domainTmp = grid->getDomains();
       if ((1<axisTmp.size()) || (1<domainTmp.size()))
         ERROR("void CField::updateRef(CGrid* grid)",
           << "More than one domain or axis is available for domain_ref/axis_ref of field " << this->getId());

       if ((!domain_ref.isEmpty()) && (domainTmp.empty()))
         ERROR("void CField::updateRef(CGrid* grid)",
           << "Incoherent between available domain and domain_ref of field " << this->getId());
       if ((!axis_ref.isEmpty()) && (axisTmp.empty()))
         ERROR("void CField::updateRef(CGrid* grid)",
           << "Incoherent between available axis and axis_ref of field " << this->getId());

       if (!domain_ref.isEmpty()) domain_ref.setValue(domainTmp[0]->getId());
       if (!axis_ref.isEmpty()) axis_ref.setValue(axisTmp[0]->getId());
     }
   }

   void CField::solveAllReferenceEnabledField(bool doSending2Server)
   {
     CContext* context = CContext::getCurrent();
     solveOnlyReferenceEnabledField(doSending2Server);

     if (!areAllReferenceSolved)
     {
        areAllReferenceSolved = true;

        if (context->hasClient)
        {
          solveRefInheritance(true);
          if (hasDirectFieldReference()) getDirectFieldReference()->solveAllReferenceEnabledField(false);
        }
        else if (context->hasServer)
          solveServerOperation();

        solveGridReference();
     }

     solveGridDomainAxisRef(doSending2Server);

     if (context->hasClient)
     {
       solveTransformedGrid();
     }

     solveCheckMaskIndex(doSending2Server);
   }

   std::map<int, StdSize> CField::getGridAttributesBufferSize()
   {
     return grid->getAttributesBufferSize();
   }

   std::map<int, StdSize> CField::getGridDataBufferSize()
   {
     return grid->getDataBufferSize(getId());
   }

   //----------------------------------------------------------------

   void CField::solveServerOperation(void)
   {
      CContext* context = CContext::getCurrent();

      if (!context->hasServer || !hasOutputFile) return;

      if (freq_op.isEmpty())
        freq_op.setValue(TimeStep);

      if (freq_offset.isEmpty())
        freq_offset.setValue(NoneDu);

      freq_operation_srv = file->output_freq.getValue();
      freq_write_srv     = file->output_freq.getValue();

      lastlast_Write_srv = context->getCalendar()->getInitDate();
      last_Write_srv     = context->getCalendar()->getInitDate();
      last_operation_srv = context->getCalendar()->getInitDate();

      const CDuration toffset = freq_operation_srv - freq_offset.getValue() - context->getCalendar()->getTimeStep();
      last_operation_srv     = last_operation_srv - toffset;

      if (operation.isEmpty())
        ERROR("void CField::solveServerOperation(void)",
              << "An operation must be defined for field \"" << getId() << "\".");

      boost::shared_ptr<func::CFunctor> functor;
      CArray<double, 1> dummyData;

#define DECLARE_FUNCTOR(MType, mtype) \
      if (operation.getValue().compare(#mtype) == 0) \
      { \
        functor.reset(new func::C##MType(dummyData)); \
      }

#include "functor_type.conf"

      if (!functor)
        ERROR("void CField::solveServerOperation(void)",
              << "\"" << operation << "\" is not a valid operation.");

      operationTimeType = functor->timeType();
   }

   //----------------------------------------------------------------

   /*!
    * Constructs the graph filter for the field, enabling or not the data output.
    * This method should not be called more than once with enableOutput equal to true.
    *
    * \param gc the garbage collector to use when building the filter graph
    * \param enableOutput must be true when the field data is to be
    *                     read by the client or/and written to a file
    */
   void CField::buildFilterGraph(CGarbageCollector& gc, bool enableOutput)
   {
     if (!areAllReferenceSolved) solveAllReferenceEnabledField(false);

     const bool detectMissingValues = (!detect_missing_value.isEmpty() && !default_value.isEmpty() && detect_missing_value == true);
     const double defaultValue  = detectMissingValues ? default_value : (!default_value.isEmpty() ? default_value : 0.0);

     // Start by building a filter which can provide the field's instant data
     if (!instantDataFilter)
     {
       // Check if we have an expression to parse
       if (hasExpression())
       {
         boost::scoped_ptr<IFilterExprNode> expr(parseExpr(getExpression() + '\0'));
         boost::shared_ptr<COutputPin> filter = expr->reduce(gc, *this);

         // Check if a spatial transformation is needed
         if (!field_ref.isEmpty())
         {
           CGrid* gridRef = CField::get(field_ref)->grid;

           if (grid && grid != gridRef && grid->hasTransform())
           {
             std::pair<boost::shared_ptr<CFilter>, boost::shared_ptr<CFilter> > filters = CSpatialTransformFilter::buildFilterGraph(gc, gridRef, grid, detectMissingValues, defaultValue);

             filter->connectOutput(filters.first, 0);
             filter = filters.second;
           }
         }

         instantDataFilter = filter;
       }
       // Check if we have a reference on another field
       else if (!field_ref.isEmpty())
         instantDataFilter = getFieldReference(gc);
       // Check if the data is to be read from a file
       else if (file && !file->mode.isEmpty() && file->mode == CFile::mode_attr::read)
       {
         checkAttributes();
         instantDataFilter = serverSourceFilter = boost::shared_ptr<CSourceFilter>(new CSourceFilter(gc, grid, freq_offset, true,
                                                                                                     detectMissingValues, defaultValue));
       }
       else // The data might be passed from the model
       {
          if (check_if_active.isEmpty()) check_if_active = false;
          instantDataFilter = clientSourceFilter = boost::shared_ptr<CSourceFilter>(new CSourceFilter(gc, grid, NoneDu, false,
                                                                                                      detectMissingValues, defaultValue));
       }
     }

     // If the field data is to be read by the client or/and written to a file
     if (enableOutput && !storeFilter && !fileWriterFilter)
     {
       if (!read_access.isEmpty() && read_access)
       {
         storeFilter = boost::shared_ptr<CStoreFilter>(new CStoreFilter(gc, CContext::getCurrent(), grid,
                                                                        detectMissingValues, defaultValue));
         instantDataFilter->connectOutput(storeFilter, 0);
       }

       if (file && (file->mode.isEmpty() || file->mode == CFile::mode_attr::write))
       {
         fileWriterFilter = boost::shared_ptr<CFileWriterFilter>(new CFileWriterFilter(gc, this));
         getTemporalDataFilter(gc, file->output_freq)->connectOutput(fileWriterFilter, 0);
       }
     }
   }

   /*!
    * Returns the filter needed to handle the field reference.
    * This method should only be called when building the filter graph corresponding to the field.
    *
    * \param gc the garbage collector to use
    * \return the output pin corresponding to the field reference
    */
   boost::shared_ptr<COutputPin> CField::getFieldReference(CGarbageCollector& gc)
   {
     if (instantDataFilter || field_ref.isEmpty())
       ERROR("COutputPin* CField::getFieldReference(CGarbageCollector& gc)",
             "Impossible to get the field reference for a field which has already been parsed or which does not have a field_ref.");

     CField* fieldRef = CField::get(field_ref);
     fieldRef->buildFilterGraph(gc, false);

     std::pair<boost::shared_ptr<CFilter>, boost::shared_ptr<CFilter> > filters;
     // Check if a spatial transformation is needed
     if (grid && grid != fieldRef->grid && grid->hasTransform())
     {       
       bool hasMissingValue = (!detect_missing_value.isEmpty() && !default_value.isEmpty() && detect_missing_value == true);
       double defaultValue  = hasMissingValue ? default_value : (!default_value.isEmpty() ? default_value : 0.0);                                
       filters = CSpatialTransformFilter::buildFilterGraph(gc, fieldRef->grid, grid, hasMissingValue, defaultValue);
     }
     else
       filters.first = filters.second = boost::shared_ptr<CFilter>(new CPassThroughFilter(gc));

     fieldRef->getInstantDataFilter()->connectOutput(filters.first, 0);

     return filters.second;
   }

   /*!
    * Returns the filter needed to handle a self reference in the field's expression.
    * If the needed filter does not exist, it is created, otherwise it is reused.
    * This method should only be called when building the filter graph corresponding
    * to the field's expression.
    *
    * \param gc the garbage collector to use
    * \return the output pin corresponding to a self reference
    */
   boost::shared_ptr<COutputPin> CField::getSelfReference(CGarbageCollector& gc)
   {
     if (instantDataFilter || !hasExpression())
       ERROR("COutputPin* CField::getSelfReference(CGarbageCollector& gc)",
             "Impossible to add a self reference to a field which has already been parsed or which does not have an expression.");

     if (!selfReferenceFilter)
     {
       const bool detectMissingValues = (!detect_missing_value.isEmpty() && !default_value.isEmpty() && detect_missing_value == true);
       const double defaultValue  = detectMissingValues ? default_value : (!default_value.isEmpty() ? default_value : 0.0);

       if (file && !file->mode.isEmpty() && file->mode == CFile::mode_attr::read)
       {
         if (!serverSourceFilter)
         {
           checkAttributes();
           serverSourceFilter = boost::shared_ptr<CSourceFilter>(new CSourceFilter(gc, grid, freq_offset, true,
                                                                                   detectMissingValues, defaultValue));
         }

         selfReferenceFilter = serverSourceFilter;
       }
       else if (!field_ref.isEmpty())
       {
         CField* fieldRef = CField::get(field_ref);
         fieldRef->buildFilterGraph(gc, false); 
         selfReferenceFilter = fieldRef->getInstantDataFilter();
       }
       else
       {
         if (!clientSourceFilter)
         {
           if (check_if_active.isEmpty()) check_if_active = false;
           clientSourceFilter = boost::shared_ptr<CSourceFilter>(new CSourceFilter(gc, grid, NoneDu, false,
                                                                                   detectMissingValues, defaultValue));
         }

         selfReferenceFilter = clientSourceFilter;
       }
     }

     return selfReferenceFilter;
   }

   /*!
    * Returns the temporal filter corresponding to the field's temporal operation
    * for the specified operation frequency. The filter is created if it does not
    * exist, otherwise it is reused.
    *
    * \param gc the garbage collector to use
    * \param outFreq the operation frequency, i.e. the frequency at which the output data will be computed
    * \return the output pin corresponding to the requested temporal filter
    */
   boost::shared_ptr<COutputPin> CField::getTemporalDataFilter(CGarbageCollector& gc, CDuration outFreq)
   {
     std::map<CDuration, boost::shared_ptr<COutputPin> >::iterator it = temporalDataFilters.find(outFreq);

     if (it == temporalDataFilters.end())
     {
       if (operation.isEmpty())
         ERROR("void CField::getTemporalDataFilter(CGarbageCollector& gc, CDuration outFreq)",
               << "An operation must be defined for field \"" << getId() << "\".");

       checkAttributes();

       const bool detectMissingValues = (!detect_missing_value.isEmpty() && !default_value.isEmpty() && detect_missing_value == true);
       boost::shared_ptr<CTemporalFilter> temporalFilter(new CTemporalFilter(gc, operation,
                                                                             CContext::getCurrent()->getCalendar()->getInitDate(),
                                                                             freq_op, freq_offset, outFreq,
                                                                             detectMissingValues, detectMissingValues ? default_value : 0.0));
       instantDataFilter->connectOutput(temporalFilter, 0);

       it = temporalDataFilters.insert(std::make_pair(outFreq, temporalFilter)).first;
     }

     return it->second;
   }

  /*!
    * Returns the temporal filter corresponding to the field's temporal operation
    * for the specified operation frequency.
    *
    * \param gc the garbage collector to use
    * \param outFreq the operation frequency, i.e. the frequency at which the output data will be computed
    * \return the output pin corresponding to the requested temporal filter
    */
   
   boost::shared_ptr<COutputPin> CField::getSelfTemporalDataFilter(CGarbageCollector& gc, CDuration outFreq)
   {
     if (instantDataFilter || !hasExpression())
       ERROR("COutputPin* CField::getSelfTemporalDataFilter(CGarbageCollector& gc)",
             "Impossible to add a self reference to a field which has already been parsed or which does not have an expression.");

     if (!selfReferenceFilter) getSelfReference(gc) ;

     if (serverSourceFilter || clientSourceFilter)
     {
       if (operation.isEmpty())
         ERROR("void CField::getSelfTemporalDataFilter(CGarbageCollector& gc, CDuration outFreq)",
               << "An operation must be defined for field \"" << getId() << "\".");

       checkAttributes();

       const bool detectMissingValues = (!detect_missing_value.isEmpty() && !default_value.isEmpty() && detect_missing_value == true);
       boost::shared_ptr<CTemporalFilter> temporalFilter(new CTemporalFilter(gc, operation,
                                                                             CContext::getCurrent()->getCalendar()->getInitDate(),
                                                                             freq_op, freq_offset, outFreq,
                                                                             detectMissingValues, detectMissingValues ? default_value : 0.0));
       selfReferenceFilter->connectOutput(temporalFilter, 0);
       return temporalFilter ;
     }
     else if (!field_ref.isEmpty())
     {
       CField* fieldRef = CField::get(field_ref);
       fieldRef->buildFilterGraph(gc, false); 
       return fieldRef->getTemporalDataFilter(gc, outFreq) ;
     }
  }

   //----------------------------------------------------------------
/*
   void CField::fromBinary(StdIStream& is)
   {
      SuperClass::fromBinary(is);
#define CLEAR_ATT(name_)\
      SuperClassAttribute::operator[](#name_)->reset()

         CLEAR_ATT(domain_ref);
         CLEAR_ATT(axis_ref);
#undef CLEAR_ATT

   }
*/
   //----------------------------------------------------------------

   void CField::solveGridReference(void)
   {
      if (grid_ref.isEmpty() && domain_ref.isEmpty() && axis_ref.isEmpty() && scalar_ref.isEmpty())
      {
        ERROR("CField::solveGridReference(void)",
              << "A grid must be defined for field '" << getFieldOutputName() << "' .");
      }
      else if (!grid_ref.isEmpty() && (!domain_ref.isEmpty() || !axis_ref.isEmpty() || !scalar_ref.isEmpty()))
      {
        ERROR("CField::solveGridReference(void)",
              << "Field '" << getFieldOutputName() << "' has both a grid and a domain/axis/scalar." << std::endl
              << "Please define either 'grid_ref' or 'domain_ref'/'axis_ref'/'scalar_ref'.");
      }

      if (grid_ref.isEmpty())
      {
        std::vector<CDomain*> vecDom;
        std::vector<CAxis*> vecAxis;
        std::vector<CScalar*> vecScalar;
        std::vector<int> axisDomainOrderTmp;
        
        if (!domain_ref.isEmpty())
        {
          StdString tmp = domain_ref.getValue();
          if (CDomain::has(domain_ref))
          {
            vecDom.push_back(CDomain::get(domain_ref));
            axisDomainOrderTmp.push_back(2);
          }
          else
            ERROR("CField::solveGridReference(void)",
                  << "Invalid reference to domain '" << domain_ref.getValue() << "'.");
        }

        if (!axis_ref.isEmpty())
        {
          if (CAxis::has(axis_ref))
          {
            vecAxis.push_back(CAxis::get(axis_ref));
            axisDomainOrderTmp.push_back(1);
          }
          else
            ERROR("CField::solveGridReference(void)",
                  << "Invalid reference to axis '" << axis_ref.getValue() << "'.");
        }

        if (!scalar_ref.isEmpty())
        {
          if (CScalar::has(scalar_ref))
          {
            vecScalar.push_back(CScalar::get(scalar_ref));
            axisDomainOrderTmp.push_back(0);
          }
          else
            ERROR("CField::solveGridReference(void)",
                  << "Invalid reference to scalar '" << scalar_ref.getValue() << "'.");
        }
        
        CArray<int,1> axisDomainOrder(axisDomainOrderTmp.size());
        for (int idx = 0; idx < axisDomainOrderTmp.size(); ++idx)
        {
          axisDomainOrder(idx) = axisDomainOrderTmp[idx];
        }

        // Warning: the gridId shouldn't be set as the grid_ref since it could be inherited
        StdString gridId = CGrid::generateId(vecDom, vecAxis, vecScalar,axisDomainOrder);
        if (CGrid::has(gridId))
          this->grid = CGrid::get(gridId);
        else
          this->grid = CGrid::createGrid(gridId, vecDom, vecAxis, vecScalar,axisDomainOrder);
      }
      else
      {
        if (CGrid::has(grid_ref))
          this->grid = CGrid::get(grid_ref);
        else
          ERROR("CField::solveGridReference(void)",
                << "Invalid reference to grid '" << grid_ref.getValue() << "'.");
      }
   }

   void CField::solveGridDomainAxisRef(bool checkAtt)
   {
     grid->solveDomainAxisRef(checkAtt);
   }

   void CField::solveCheckMaskIndex(bool doSendingIndex)
   {
     grid->checkMaskIndex(doSendingIndex);
   }

   void CField::solveTransformedGrid()
   {
     if (grid && !grid->isTransformed() && hasDirectFieldReference() && grid != getDirectFieldReference()->grid)
     {
       std::vector<CGrid*> grids;
       // Source grid
       grids.push_back(getDirectFieldReference()->grid);
       // Intermediate grids
       if (!grid_path.isEmpty())
       {
         std::string gridId;
         size_t start = 0, end;

         do
         {
           end = grid_path.getValue().find(',', start);
           if (end != std::string::npos)
           {
             gridId = grid_path.getValue().substr(start, end - start);
             start = end + 1;
           }
           else
             gridId = grid_path.getValue().substr(start);

           if (!CGrid::has(gridId))
             ERROR("void CField::solveTransformedGrid()",
                   << "Invalid grid_path, the grid '" << gridId << "' does not exist.");

           grids.push_back(CGrid::get(gridId));
         }
         while (end != std::string::npos);
       }
       // Destination grid
       grids.push_back(grid);

       for (size_t i = 0, count = grids.size() - 1; i < count; ++i)
       {
         CGrid *gridSrc  = grids[i];
         CGrid *gridDest = grids[i + 1];
         if (!gridDest->isTransformed())
           gridDest->transformGrid(gridSrc);
       }
     }
     else if (grid && grid->hasTransform() && !grid->isTransformed())
     {
       // Temporarily deactivate the self-transformation of grid
       grid->transformGrid(grid);
     }
   }

   void CField::solveGenerateGrid()
   {
     if (grid && !grid->isTransformed() && hasDirectFieldReference() && grid != getDirectFieldReference()->grid)
       grid->completeGrid(getDirectFieldReference()->grid);
     else
       grid->completeGrid();
   }

   void CField::solveGridDomainAxisBaseRef()
   {
     grid->solveDomainAxisRef(false);
     grid->solveDomainAxisBaseRef();
   }

   ///-------------------------------------------------------------------

   template <>
   void CGroupTemplate<CField, CFieldGroup, CFieldAttributes>::solveRefInheritance(void)
   {
      if (this->group_ref.isEmpty()) return;
      StdString gref = this->group_ref.getValue();

      if (!CFieldGroup::has(gref))
         ERROR("CGroupTemplate<CField, CFieldGroup, CFieldAttributes>::solveRefInheritance(void)",
               << "[ gref = " << gref << "]"
               << " invalid group name !");

      CFieldGroup* group = CFieldGroup::get(gref);
      CFieldGroup* owner = CFieldGroup::get(boost::polymorphic_downcast<CFieldGroup*>(this));

      std::vector<CField*> allChildren  = group->getAllChildren();
      std::vector<CField*>::iterator it = allChildren.begin(), end = allChildren.end();

      for (; it != end; it++)
      {
         CField* child = *it;
         if (child->hasId()) owner->createChild()->field_ref.setValue(child->getId());

      }
   }

   void CField::scaleFactorAddOffset(double scaleFactor, double addOffset)
   {
     map<int, CArray<double,1> >::iterator it;
     for (it = data_srv.begin(); it != data_srv.end(); it++) it->second = (it->second - addOffset) / scaleFactor;
   }

   void CField::invertScaleFactorAddOffset(double scaleFactor, double addOffset)
   {
     map<int, CArray<double,1> >::iterator it;
     for (it = data_srv.begin(); it != data_srv.end(); it++) it->second = it->second * scaleFactor + addOffset;
   }

   void CField::outputField(CArray<double,3>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;
      for (it = data_srv.begin(); it != data_srv.end(); it++)
      {
        grid->outputField(it->first, it->second, fieldOut.dataFirst());
      }
   }

   void CField::outputField(CArray<double,2>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;
      for(it=data_srv.begin();it!=data_srv.end();it++)
      {
         grid->outputField(it->first, it->second, fieldOut.dataFirst());
      }
   }

   void CField::outputField(CArray<double,1>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;

      for (it = data_srv.begin(); it != data_srv.end(); it++)
      {
         grid->outputField(it->first, it->second, fieldOut.dataFirst());
      }
   }

   void CField::inputField(CArray<double,3>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;
      for (it = data_srv.begin(); it != data_srv.end(); it++)
      {
        grid->inputField(it->first, fieldOut.dataFirst(), it->second);
      }
   }

   void CField::inputField(CArray<double,2>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;
      for(it = data_srv.begin(); it != data_srv.end(); it++)
      {
         grid->inputField(it->first, fieldOut.dataFirst(), it->second);
      }
   }

   void CField::inputField(CArray<double,1>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;
      for (it = data_srv.begin(); it != data_srv.end(); it++)
      {
         grid->inputField(it->first, fieldOut.dataFirst(), it->second);
      }
   }

   void CField::outputCompressedField(CArray<double,1>& fieldOut)
   {
      map<int, CArray<double,1> >::iterator it;

      for (it = data_srv.begin(); it != data_srv.end(); it++)
      {
         grid->outputCompressedField(it->first, it->second, fieldOut.dataFirst());
      }
   }

   ///-------------------------------------------------------------------

   void CField::parse(xml::CXMLNode& node)
   {
      SuperClass::parse(node);
      if (!node.getContent(this->content))
      {
        if (node.goToChildElement())
        {
          do
          {
            if (node.getElementName() == "variable" || node.getElementName() == "variable_group") this->getVirtualVariableGroup()->parseChild(node);
          } while (node.goToNextElement());
          node.goToParentElement();
        }
      }
    }

   /*!
     This function retrieves Id of corresponding domain_ref and axis_ref (if any)
   of a field. In some cases, only domain exists but axis doesn't
   \return pair of Domain and Axis id
   */
   const std::vector<StdString>& CField::getRefDomainAxisIds()
   {
     CGrid* cgPtr = getRelGrid();
     if (NULL != cgPtr)
     {
       std::vector<StdString>::iterator it;
       if (!domain_ref.isEmpty())
       {
         std::vector<StdString> domainList = cgPtr->getDomainList();
         it = std::find(domainList.begin(), domainList.end(), domain_ref.getValue());
         if (domainList.end() != it) domAxisScalarIds_[0] = *it;
       }

       if (!axis_ref.isEmpty())
       {
         std::vector<StdString> axisList = cgPtr->getAxisList();
         it = std::find(axisList.begin(), axisList.end(), axis_ref.getValue());
         if (axisList.end() != it) domAxisScalarIds_[1] = *it;
       }

       if (!scalar_ref.isEmpty())
       {
         std::vector<StdString> scalarList = cgPtr->getScalarList();
         it = std::find(scalarList.begin(), scalarList.end(), scalar_ref.getValue());
         if (scalarList.end() != it) domAxisScalarIds_[2] = *it;
       }
     }
     return (domAxisScalarIds_);
   }

   CVariable* CField::addVariable(const string& id)
   {
     return vVariableGroup->createChild(id);
   }

   CVariableGroup* CField::addVariableGroup(const string& id)
   {
     return vVariableGroup->createChildGroup(id);
   }

   void CField::sendAddAllVariables()
   {
     std::vector<CVariable*> allVar = getAllVariables();
     std::vector<CVariable*>::const_iterator it = allVar.begin();
     std::vector<CVariable*>::const_iterator itE = allVar.end();

     for (; it != itE; ++it)
     {
       this->sendAddVariable((*it)->getId());
       (*it)->sendAllAttributesToServer();
       (*it)->sendValue();
     }
   }

   void CField::sendAddVariable(const string& id)
   {
    CContext* context = CContext::getCurrent();

    if (!context->hasServer)
    {
       CContextClient* client = context->client;

       CEventClient event(this->getType(),EVENT_ID_ADD_VARIABLE);
       if (client->isServerLeader())
       {
         CMessage msg;
         msg << this->getId();
         msg << id;
         const std::list<int>& ranks = client->getRanksServerLeader();
         for (std::list<int>::const_iterator itRank = ranks.begin(), itRankEnd = ranks.end(); itRank != itRankEnd; ++itRank)
           event.push(*itRank,1,msg);
         client->sendEvent(event);
       }
       else client->sendEvent(event);
    }
   }

   void CField::sendAddVariableGroup(const string& id)
   {
    CContext* context = CContext::getCurrent();
    if (!context->hasServer)
    {
       CContextClient* client = context->client;

       CEventClient event(this->getType(),EVENT_ID_ADD_VARIABLE_GROUP);
       if (client->isServerLeader())
       {
         CMessage msg;
         msg << this->getId();
         msg << id;
         const std::list<int>& ranks = client->getRanksServerLeader();
         for (std::list<int>::const_iterator itRank = ranks.begin(), itRankEnd = ranks.end(); itRank != itRankEnd; ++itRank)
           event.push(*itRank,1,msg);
         client->sendEvent(event);
       }
       else client->sendEvent(event);
    }
   }

   void CField::recvAddVariable(CEventServer& event)
   {

      CBufferIn* buffer = event.subEvents.begin()->buffer;
      string id;
      *buffer >> id;
      get(id)->recvAddVariable(*buffer);
   }

   void CField::recvAddVariable(CBufferIn& buffer)
   {
      string id;
      buffer >> id;
      addVariable(id);
   }

   void CField::recvAddVariableGroup(CEventServer& event)
   {

      CBufferIn* buffer = event.subEvents.begin()->buffer;
      string id;
      *buffer >> id;
      get(id)->recvAddVariableGroup(*buffer);
   }

   void CField::recvAddVariableGroup(CBufferIn& buffer)
   {
      string id;
      buffer >> id;
      addVariableGroup(id);
   }

   /*!
    * Check on freq_off and freq_op attributes.
    */
   void CField::checkAttributes(void)
   {
     bool isFieldRead = file && !file->mode.isEmpty() && file->mode == CFile::mode_attr::read;
     if (isFieldRead && operation.getValue() != "instant")
       ERROR("void CField::checkAttributes(void)",
             << "Unsupported operation for field '" << getFieldOutputName() << "'." << std::endl
             << "Currently only \"instant\" is supported for fields read from file.")

     if (freq_op.isEmpty())
     {
       if (operation.getValue() == "instant")
         freq_op.setValue(file->output_freq.getValue());
       else
         freq_op.setValue(TimeStep);
     }
     if (freq_offset.isEmpty())
       freq_offset.setValue(isFieldRead ? NoneDu : (freq_op.getValue() - TimeStep));
   }

   /*!
    * Returns string arithmetic expression associated to the field.
    * \return if content is defined return content string, otherwise, if "expr" attribute is defined, return expr string.
    */
   const string& CField::getExpression(void)
   {
     if (!expr.isEmpty() && content.empty())
     {
       content = expr;
       expr.reset();
     }

     return content;
   }

   bool CField::hasExpression(void) const
   {
     return (!expr.isEmpty() || !content.empty());
   }

   DEFINE_REF_FUNC(Field,field)
} // namespace xios