
/*=========================================================================
 *
 *  Portions of this file are subject to the VTK Toolkit Version 3 copyright.
 *
 *  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
 *
 *  For complete copyright, license and disclaimer of warranty information
 *  please refer to the NOTICE file at the top of the ITK source tree.
 *
 *=========================================================================*/
#ifndef itkFEMFactoryBase_h
#define itkFEMFactoryBase_h

#include "itkObjectFactoryBase.h"
#include "itkSimpleFastMutexLock.h"
#include "ITKFEMExport.h"

namespace itk
{
/** \class FEMFactoryBase
 * \brief Create instances of FEM Objects.
 * This includes Elements, Loads, and Materials
 * \ingroup ITKFEM
 */

class ITKFEM_EXPORT FEMFactoryBase : public ObjectFactoryBase
{
public:
  ITK_DISALLOW_COPY_AND_ASSIGN(FEMFactoryBase);

  /** Standard class type aliases. */
  using Self = FEMFactoryBase;
  using Superclass = ObjectFactoryBase;
  using Pointer = SmartPointer<Self>;
  using ConstPointer = SmartPointer<const Self>;

  /** Class methods used to interface with the registered factories. */
  const char * GetITKSourceVersion() const override;

  const char * GetDescription() const override;

  /** Run-time type information (and related methods). */
  itkTypeMacro(FEMFactoryBase, ObjectFactoryBase);

  /** Method for class instantiation. */
  itkFactorylessNewMacro(Self);

  /** Register all builtin transforms */
  static void RegisterDefaultTypes();  //HACK: This should not have a public interface since it does nothing except during instantiation of the class.

  /** Register this transform */
  static FEMFactoryBase * GetFactory()
  {
    if( m_Factory == nullptr )
      {
      m_CreationLock.Lock();
      //Need to make sure that during gaining access
      //to the lock that some other thread did not
      //initialize the singleton.
      if( m_Factory == nullptr )
        {
        // Make and register the factory
        FEMFactoryBase::Pointer p = FEMFactoryBase::New();
        if( p.IsNull() )
          {
          std::ostringstream message;
          message << "itk::ERROR: " << "FEMFactoryBase"
            << " instance not created";
          ::itk::ExceptionObject e_(__FILE__, __LINE__, message.str().c_str(), ITK_LOCATION);
          throw e_; /* Explicit naming to work around for Intel compiler bug. */
          }
        ObjectFactoryBase::RegisterFactory( p );
        m_Factory = p.GetPointer();
        }
      m_CreationLock.Unlock();
      m_Factory->RegisterDefaultTypes(); //Not initialzie all default types.
      }
    return m_Factory;
  }

  void RegisterType(const char* classOverride,
                    const char* overrideClassName,
                    const char* description,
                    bool enableFlag,
                    CreateObjectFunctionBase* createFunction)
  {
    this->RegisterOverride( classOverride, overrideClassName, description, enableFlag, createFunction );
  }

protected:
  FEMFactoryBase();
  ~FEMFactoryBase() override;

private:
  static SimpleFastMutexLock m_CreationLock;
  static FEMFactoryBase*     m_Factory;
};
} // end namespace itk

#endif // itkFEMFactoryBase_h
