//                                               -*- C++ -*-
/**
 *  @file  ComputedNumericalMathGradientImplementation.hxx
 *  @brief Abstract top-level class for all ComputedNumerical math functions
 *
 *  (C) Copyright 2005-2012 EDF-EADS-Phimeca
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 *  @author schueller
 *  @date   2012-02-17 19:35:43 +0100 (Fri, 17 Feb 2012)
 *  Id      ComputedNumericalMathGradientImplementation.hxx 2392 2012-02-17 18:35:43Z schueller
 */
#ifndef OPENTURNS_COMPUTEDNUMERICALMATHGRADIENTIMPLEMENTATION_HXX
#define OPENTURNS_COMPUTEDNUMERICALMATHGRADIENTIMPLEMENTATION_HXX

#include "NumericalMathGradientImplementation.hxx"
#include "Pointer.hxx"
#include "NumericalPoint.hxx"
#include "Matrix.hxx"
#include "WrapperFile.hxx"

BEGIN_NAMESPACE_OPENTURNS




/* Forward declaration */
class WrapperObject;

/**
 * @class ComputedNumericalMathGradientImplementation
 *
 * This class acts like an real numerical mathematical gradient
 * into the platform. It realizes the computation of the image vector
 * of a vector (aka NumericalPoint) through the function. The
 * function may be loaded in an external way through a wrapper.
 */
class ComputedNumericalMathGradientImplementation
  : public NumericalMathGradientImplementation
{
  CLASSNAME;

public:

  /* Some typedefs to ease reading */
  typedef Pointer<WrapperObject>                                InternalGradient;

  /** Default constructor */
  ComputedNumericalMathGradientImplementation(const String & name, const WrapperFile & file, void * p_state = 0);

  /** Copy constructor */
  ComputedNumericalMathGradientImplementation(const ComputedNumericalMathGradientImplementation & other);

  /** Virtual constructor */
  virtual ComputedNumericalMathGradientImplementation * clone() const;

  /** Destructor */
  virtual ~ComputedNumericalMathGradientImplementation();

  /** Comparison operator */
  Bool operator ==(const ComputedNumericalMathGradientImplementation & other) const;

  /** String converter */
  String __repr__() const;
  virtual String __str__(const String & offset = "") const;



  /* Here is the interface that all derived class must implement */

  /** Gradient method */
  virtual Matrix gradient(const NumericalPoint & inP) const;

  /** Accessor for input point dimension */
  virtual UnsignedLong getInputDimension() const;

  /** Accessor for output point dimension */
  virtual UnsignedLong getOutputDimension() const;

  /** Method save() stores the object through the StorageManager */
  void save(Advocate & adv) const;

  /** Method load() reloads the object from the StorageManager */
  void load(Advocate & adv);

protected:

  /** The function object that is linked to the external code */
  InternalGradient p_gradient_;

  /** State management */
  void * getState() const;

private:
  ComputedNumericalMathGradientImplementation() {};
  friend class Factory<ComputedNumericalMathGradientImplementation>;

  /** A pointer to an internal structure that saves the state of the function into the wrapper */
  void * p_state_;

  /** A flag that is true when the gradient shares its internal state with its related function */
  Bool commonState_;

}; /* class ComputedNumericalMathGradientImplementation */


END_NAMESPACE_OPENTURNS

#endif /* OPENTURNS_COMPUTEDNUMERICALMATHGRADIENTIMPLEMENTATION_HXX */
