// DatasetMergerCreator.cxx

#include "dataset_split/DatasetMergerCreator.h"
#include <iostream>
#include "dataset_util/XmlElement.h"

using std::string;
using std::ostream;
using dset::DatasetMergerCreator;

typedef DatasetMergerCreator::Creator Creator;
typedef DatasetMergerCreator::CreatorList CreatorList;
typedef std::map<string, Creator> CreatorMap;

//**********************************************************************
// Local definitions.
//**********************************************************************

namespace {

// Map of functions indexed by XML name.
CreatorMap& creator_map() {
  static CreatorMap cmap;
  return cmap;
}

// List of known creators.
CreatorList& creator_list() {
  static CreatorList clist;
  return clist;
}

}  // end unnamed namespace

//**********************************************************************
// Static member functions.
//**********************************************************************

// Create a DatasetMergerCreator.

const DatasetMergerCreator* 
DatasetMergerCreator::create(const XmlElement& ele) {
  CreatorMap& cres = creator_map();
  CreatorMap::const_iterator icre = cres.find(ele.name());
  if ( icre == cres.end() ) {
    return 0;
  }
  Creator cre = icre->second;
  const DatasetMergerCreator* pjcr = cre(ele);
  return pjcr;
}

//**********************************************************************

// Register a creator.

int DatasetMergerCreator::
register_creator(std::string name, Creator pfun) {
  CreatorMap& cres = creator_map();
  CreatorMap::const_iterator icre = cres.find(name);
  if ( icre != cres.end() ) {
    if ( icre->second == pfun ) return 0;
    return 1;
  }
  if ( pfun == 0 ) return 2;
  cres[name] = pfun;
  creator_list().push_back(name);
  return 0;
}

//**********************************************************************

// Return the known creators.

const CreatorList& DatasetMergerCreator::creators() {
  return creator_list();
}

//**********************************************************************

// Return if a creator is registered.

bool DatasetMergerCreator::has_creator(std::string name) {
  CreatorMap& cres = creator_map();
  CreatorMap::const_iterator icre = cres.find(name);
  return icre != cres.end();
}

//**********************************************************************
// Member functions.
//**********************************************************************

// Destructor.

DatasetMergerCreator::~DatasetMergerCreator() { }

//**********************************************************************

// Output stream.

ostream& operator<<(ostream& lhs, const DatasetMergerCreator& rhs) {
   return rhs.ostr(lhs);
}

//**********************************************************************