/*=========================================================================

  Program:   Insight Segmentation & Registration Toolkit
  Module:    itkListSample.h
  Language:  C++
  Date:      $Date$
  Version:   $Revision$

  Copyright (c) Insight Software Consortium. All rights reserved.
  See ITKCopyright.txt or http://www.itk.org/HTML/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notices for more information.

=========================================================================*/
#ifndef __itkListSample_h
#define __itkListSample_h

#include "itkObjectFactory.h"
#include "itkFixedArray.h"
#include "itkSample.h"

#include <vector>

namespace itk {
namespace Statistics {

/** \class ListSample
 *  \brief This class is the native implementation of the a Sample with an STL container
 *
 * ListSample stores measurements in a list type structure (as opposed to a
 * Histogram, etc.).  ListSample allows duplicate measurements. ListSample is
 * not sorted.
 *
 * ListSample does not allow the user to specify the frequency of
 * a measurement directly.  The GetFrequency() methods returns 1 if
 * the measurement exists in the list, 0 otherwise.
 *
 *\sa Sample, Histogram
 */

template< class TMeasurementVector >
class ITK_EXPORT ListSample : public Sample< TMeasurementVector >
{
public:
  /** Standard class typedef. */
  typedef ListSample                     Self;
  typedef Sample< TMeasurementVector >   Superclass;
  typedef SmartPointer< Self >           Pointer;
  typedef SmartPointer<const Self>       ConstPointer;

  /** Standard macros */
  itkTypeMacro(ListSample, Sample);

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** Typedefs inherited from the superclass */
  itkSuperclassTraitMacro( MeasurementVectorType )
  itkSuperclassTraitMacro( MeasurementVectorSizeType )
  itkSuperclassTraitMacro( MeasurementType )
  itkSuperclassTraitMacro( AbsoluteFrequencyType )
  itkSuperclassTraitMacro( TotalAbsoluteFrequencyType )
  itkSuperclassTraitMacro( InstanceIdentifier )

  /** Value type of a measurement (component of the measurement
   * vector) */
  typedef MeasurementVectorType ValueType;


  /** internal data container type */
  typedef std::vector< MeasurementVectorType > InternalDataContainerType;

  /** Resize the container. Using Resize() and then SetMeasurementVector() is
   * about nine times faster than usign PushBack() continously. Which means that
   * whenever the total number of Measurement vectors is known, the users
   * should prefer calling Resize() first and then set the values by calling
   * SetMeasurementVector(). On the other hand, if the number of measurement
   * vectors is not known from the beginning, then calling PushBack()
   * sequentially is a convenient option. */
  void Resize( InstanceIdentifier newsize );

  /** Removes all the elements in the Sample */
  void Clear();

  /** Inserts a measurement at the end of the list */
  void PushBack( const MeasurementVectorType & mv );

  /** Get the number of measurement vectors in the sample */
  InstanceIdentifier Size() const;

  /** Get the measurement associated with the specified
   * InstanceIdentifier */
  const MeasurementVectorType & GetMeasurementVector(InstanceIdentifier id) const;

  /** Set a component a measurement to a particular value. */
  void SetMeasurement(InstanceIdentifier id,
                      unsigned int dim,
                      const MeasurementType &value);

  /** Replace a measurement with a different measurement */
  void SetMeasurementVector( InstanceIdentifier id,
                            const MeasurementVectorType &mv);

  /** Get the frequency of a measurement. Returns 1 if the measurement
   * exist. */
  AbsoluteFrequencyType GetFrequency( InstanceIdentifier id ) const;

  /** Get the total frequency of the sample.  This is equivalent to
   * the size of the sample. */
  TotalAbsoluteFrequencyType GetTotalFrequency() const;

  /** Method to graft another sample */
  virtual void Graft( const DataObject *thatObject );
    
  /** \class ListSample::ConstIterator */
  class ConstIterator
    {
    friend class ListSample;

    public:

    ConstIterator( const ListSample * sample )
      {
      *this = sample->Begin();
      }

    ConstIterator(const ConstIterator &iter)
      {
      m_Iter = iter.m_Iter;
      m_InstanceIdentifier = iter.m_InstanceIdentifier;
      }

    ConstIterator& operator=( const ConstIterator & iter )
      {
      m_Iter = iter.m_Iter;
      m_InstanceIdentifier = iter.m_InstanceIdentifier;
      return *this;
      }


    AbsoluteFrequencyType GetFrequency() const
      {
      return 1;
      }

    const MeasurementVectorType & GetMeasurementVector() const
      {
      return static_cast<const MeasurementVectorType&>(*m_Iter);
      }

    InstanceIdentifier GetInstanceIdentifier() const
      {
      return m_InstanceIdentifier;
      }

    ConstIterator& operator++()
      {
      ++m_Iter;
      ++m_InstanceIdentifier;
      return *this;
      }

    bool operator!=(const ConstIterator &it)
      {
      return (m_Iter != it.m_Iter);
      }

    bool operator==(const ConstIterator &it)
      {
      return (m_Iter == it.m_Iter);
      }

#if !(defined(_MSC_VER) && (_MSC_VER <= 1200))
  protected:
#endif
    // This method should only be available to the ListSample class
    ConstIterator(
      typename InternalDataContainerType::const_iterator iter,
      InstanceIdentifier iid)
      {
      m_Iter = iter;
      m_InstanceIdentifier = iid;
      }

    // This method is purposely not implemented
    ConstIterator();

  private:
    typedef typename InternalDataContainerType::const_iterator InternalIterator;
    InternalIterator     m_Iter;
    InstanceIdentifier   m_InstanceIdentifier;

    };

  /** \class ListSample::Iterator */
  class Iterator : public ConstIterator
  {

  friend class ListSample;

  public:

    Iterator(Self * sample):ConstIterator(sample)
      {
      }

    Iterator(const Iterator &iter):ConstIterator( iter )
      {
      }

    Iterator& operator =(const Iterator & iter)
      {
      this->ConstIterator::operator=( iter );
      return *this;
      }

#if !(defined(_MSC_VER) && (_MSC_VER <= 1200))
  protected:
#endif
    // To ensure const-correctness these method must not be in the public API.
    // The are purposly not implemented, since they should never be called.
    Iterator();
    Iterator(const Self * sample);
    Iterator( typename InternalDataContainerType::const_iterator iter, InstanceIdentifier iid);
    Iterator(const ConstIterator & it);
    ConstIterator& operator=(const ConstIterator& it);
    Iterator(
      typename InternalDataContainerType::iterator iter,
      InstanceIdentifier iid):ConstIterator( iter, iid )
      {
      }

  private:
  };


  /** returns an iterator that points to the beginning of the container */
  Iterator Begin()
    {
    Iterator iter(m_InternalContainer.begin(), 0);
    return iter;
    }

  /** returns an iterator that points to the end of the container */
  Iterator End()
    {
    Iterator iter(m_InternalContainer.end(), m_InternalContainer.size());
    return iter;
    }

  /** returns an iterator that points to the beginning of the container */
  ConstIterator Begin() const
    {
    ConstIterator iter(m_InternalContainer.begin(), 0);
    return iter;
    }

  /** returns an iterator that points to the end of the container */
  ConstIterator End() const
    {
    ConstIterator iter(m_InternalContainer.end(), m_InternalContainer.size());
    return iter;
    }

protected:

  ListSample();
  virtual ~ListSample() {}
  void PrintSelf(std::ostream& os, Indent indent) const;


private:
  ListSample(const Self&); //purposely not implemented
  void operator=(const Self&); //purposely not implemented

  InternalDataContainerType m_InternalContainer;

};

} // end of namespace Statistics
} // end of namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#include "itkListSample.txx"
#endif

#endif