//                                               -*- C++ -*-
/**
 *  @brief An implementation class for constant random vectors
 *
 *  Copyright 2005-2018 Airbus-EDF-IMACS-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 3 of the License, or
 *  (at your option) any later version.
 *
 *  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, see <http://www.gnu.org/licenses/>.
 *
 */
#include "openturns/PersistentObjectFactory.hxx"
#include "openturns/ConstantRandomVector.hxx"
#include "openturns/Dirac.hxx"
#include "openturns/SquareMatrix.hxx"

BEGIN_NAMESPACE_OPENTURNS

CLASSNAMEINIT(ConstantRandomVector)

static const Factory<ConstantRandomVector> Factory_ConstantRandomVector;

/* Default constructor */
ConstantRandomVector::ConstantRandomVector()
  : RandomVectorImplementation()
{}


/* Default constructor */
ConstantRandomVector::ConstantRandomVector(const PointWithDescription & point)
  : RandomVectorImplementation()
  , point_(point)
{
  // Get the description from the underlying point
  setDescription( point.getDescription() );
}

/* Parameter constructor */
ConstantRandomVector::ConstantRandomVector(const Point & point)
  : RandomVectorImplementation()
  , point_(point)
{
  //
  setDescription( Description::BuildDefault(point.getDimension(), "x") );
}


/* Virtual constructor */
ConstantRandomVector * ConstantRandomVector::clone() const
{
  return new ConstantRandomVector(*this);
}

/* String converter */
String ConstantRandomVector::__repr__() const
{
  OSS oss;
  oss << "class=" << ConstantRandomVector::GetClassName()
      << " description=" << getDescription()
      << " point=" << point_;
  return oss;
}



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


/* Dimension accessor */
UnsignedInteger ConstantRandomVector::getDimension() const
{
  return point_.getDimension();
}

/* Realization accessor */
Point ConstantRandomVector::getRealization() const
{
  return point_;
}

/* Numerical sample accessor */
Sample ConstantRandomVector::getSample(const UnsignedInteger size) const
{
  Sample sample(size, point_);
  sample.setDescription(getDescription());
  return sample;
}


Point ConstantRandomVector::getParameter() const
{
  Point parameter;
  return parameter;
}

void ConstantRandomVector::setParameter(const Point & parameter)
{
  if (parameter.getDimension() > 0)
    throw InvalidArgumentException(HERE) << "Wrong constant random vector parameter size";
}

Description ConstantRandomVector::getParameterDescription() const
{
  Description description;
  return description;
}

/* Mean accessor */
Point ConstantRandomVector::getMean() const
{
  return point_;
}

/* Covariance accessor */
CovarianceMatrix ConstantRandomVector::getCovariance() const
{
  const UnsignedInteger dimension = getDimension();
  CovarianceMatrix covariance(dimension);
  for (UnsignedInteger i = 0; i < dimension; ++i) covariance(i, i) = 0.0;
  return covariance;
}

/* Get the random vector corresponding to the i-th marginal component */
RandomVector ConstantRandomVector::getMarginal(const UnsignedInteger i) const
{
  if (i >= getDimension()) throw InvalidArgumentException(HERE) << "The index of a marginal random vector must be in the range [0, dim-1]";
  return new ConstantRandomVector(Point(1, point_[i]));
}

/* Get the marginal random vector corresponding to indices components */
RandomVector ConstantRandomVector::getMarginal(const Indices & indices) const
{
  if (!indices.check(getDimension())) throw InvalidArgumentException(HERE) << "The indices of a marginal random vector must be in the range [0, dim-1] and must be different";
  const UnsignedInteger marginalDimension = indices.getSize();
  Point marginalPoint(marginalDimension);
  for (UnsignedInteger i = 0; i < marginalDimension; ++i) marginalPoint[i] = point_[indices[i]];
  return new ConstantRandomVector(marginalPoint);
}

/* Distribution accessor */
Distribution ConstantRandomVector::getDistribution() const
{
  return Dirac(point_);
}

/* Method save() stores the object through the StorageManager */
void ConstantRandomVector::save(Advocate & adv) const
{
  RandomVectorImplementation::save(adv);
  adv.saveAttribute( "point_", point_ );
}

/* Method load() reloads the object from the StorageManager */
void ConstantRandomVector::load(Advocate & adv)
{
  RandomVectorImplementation::load(adv);
  adv.loadAttribute( "point_", point_ );
}

END_NAMESPACE_OPENTURNS
