/*
*
* Template Numerical Toolkit (TNT)
*
* Mathematical and Computational Sciences Division
* National Institute of Technology,
* Gaithersburg, MD USA
*
*
* This software was developed at the National Institute of Standards and
* Technology (NIST) by employees of the Federal Government in the course
* of their official duties. Pursuant to title 17 Section 105 of the
* United States Code, this software is not subject to copyright protection
* and is in the public domain. NIST assumes no responsibility whatsoever for
* its use by other parties, and makes no guarantees, expressed or implied,
* about its quality, reliability, or any other characteristic.
*
*/



#ifndef IMPALGEBRA_TNT_ARRAY_2D_H
#define IMPALGEBRA_TNT_ARRAY_2D_H

#include "../algebra_config.h"
#include <cstdlib>
#include <iostream>
#ifdef TNT_BOUNDS_CHECK
#include <cassert>
#endif

#include "tnt_array1d.h"

IMPALGEBRA_BEGIN_INTERNAL_NAMESPACE
namespace TNT
{
using namespace std;

template <class T>
class Array2D
{


  private:



    Array1D<T> data_;
  Array1D<T*> v_;
  int m_;
    int n_;

  public:

    typedef         T   value_type;
         Array2D();
         Array2D(int m, int n);
         Array2D(int m, int n,  T *a);
         Array2D(int m, int n, const T &a);
    inline Array2D(const Array2D &A);
  /*explicit inline operator T**();
  explicit inline operator const T**();*/
  inline Array2D & operator=(const T &a);
  inline Array2D & operator=(const Array2D &A);
  inline Array2D & ref(const Array2D &A);
         Array2D copy() const;
       Array2D & inject(const Array2D & A);
  inline T* operator[](int i);
  inline const T* operator[](int i) const;
  inline int dim1() const;
  inline int dim2() const;
     ~Array2D();

  /* extended interface (not part of the standard) */


  inline int ref_count();
  inline int ref_count_data();
  inline int ref_count_dim1();
  Array2D subarray(int i0, int i1, int j0, int j1);

};


template <class T>
Array2D<T>::Array2D() : data_(), v_(), m_(0), n_(0) {}

template <class T>
Array2D<T>::Array2D(const Array2D<T> &A) : data_(A.data_), v_(A.v_),
  m_(A.m_), n_(A.n_) {}




template <class T>
Array2D<T>::Array2D(int m, int n) : data_(m*n), v_(m), m_(m), n_(n)
{
  if (m>0 && n>0)
  {
    T* p = &(data_[0]);
    for (int i=0; i<m; i++)
    {
      v_[i] = p;
      p += n;
    }
  }
}



template <class T>
Array2D<T>::Array2D(int m, int n, const T &val) : data_(m*n), v_(m),
                          m_(m), n_(n)
{
  if (m>0 && n>0)
  {
  data_ = val;
  T* p  = &(data_[0]);
  for (int i=0; i<m; i++)
  {
      v_[i] = p;
      p += n;
  }
  }
}

template <class T>
Array2D<T>::Array2D(int m, int n, T *a) : data_(m*n, a), v_(m), m_(m), n_(n)
{
  if (m>0 && n>0)
  {
  T* p = &(data_[0]);

  for (int i=0; i<m; i++)
  {
      v_[i] = p;
      p += n;
  }
  }
}


template <class T>
inline T* Array2D<T>::operator[](int i)
{
#ifdef TNT_BOUNDS_CHECK
  assert(i >= 0);
  assert(i < m_);
#endif

return v_[i];

}


template <class T>
inline const T* Array2D<T>::operator[](int i) const
{
#ifdef TNT_BOUNDS_CHECK
  assert(i >= 0);
  assert(i < m_);
#endif

return v_[i];

}

template <class T>
Array2D<T> & Array2D<T>::operator=(const T &a)
{
  /* non-optimzied, but will work with subarrays in future verions */

  for (int i=0; i<m_; i++)
    for (int j=0; j<n_; j++)
    v_[i][j] = a;
  return *this;
}




template <class T>
Array2D<T> Array2D<T>::copy() const
{
  Array2D A(m_, n_);

  for (int i=0; i<m_; i++)
    for (int j=0; j<n_; j++)
      A[i][j] = v_[i][j];


  return A;
}


template <class T>
Array2D<T> & Array2D<T>::inject(const Array2D &A)
{
  if (A.m_ == m_ &&  A.n_ == n_)
  {
    for (int i=0; i<m_; i++)
      for (int j=0; j<n_; j++)
        v_[i][j] = A[i][j];
  }
  return *this;
}




template <class T>
Array2D<T> & Array2D<T>::ref(const Array2D<T> &A)
{
  if (this != &A)
  {
    v_ = A.v_;
    data_ = A.data_;
    m_ = A.m_;
    n_ = A.n_;

  }
  return *this;
}



template <class T>
Array2D<T> & Array2D<T>::operator=(const Array2D<T> &A)
{
  return ref(A);
}

template <class T>
inline int Array2D<T>::dim1() const { return m_; }

template <class T>
inline int Array2D<T>::dim2() const { return n_; }


template <class T>
Array2D<T>::~Array2D() {}



/*
template <class T>
inline Array2D<T>::operator T**()
{
  return &(v_[0]);
}
template <class T>
inline Array2D<T>::operator const T**()
{
  return &(v_[0]);
}*/

/* ............... extended interface ............... */
/**
  Create a new view to a subarray defined by the boundaries
  [i0][i0] and [i1][j1].  The size of the subarray is
  (i1-i0) by (j1-j0).  If either of these lengths are zero
  or negative, the subarray view is null.

*/
template <class T>
Array2D<T> Array2D<T>::subarray(int i0, int i1, int j0, int j1)
{
  Array2D<T> A;
  int m = i1-i0+1;
  int n = j1-j0+1;

  /* if either length is zero or negative, this is an invalide
    subarray. return a null view.
  */
  if (m<1 || n<1)
    return A;

  A.data_ = data_;
  A.m_ = m;
  A.n_ = n;
  A.v_ = Array1D<T*>(m);
  T* p = &(data_[0]) + i0 *  n_ + j0;
  for (int i=0; i<m; i++)
  {
    A.v_[i] = p + i*n_;

  }
  return A;
}

template <class T>
inline int Array2D<T>::ref_count()
{
  return ref_count_data();
}



template <class T>
inline int Array2D<T>::ref_count_data()
{
  return data_.ref_count();
}

template <class T>
inline int Array2D<T>::ref_count_dim1()
{
  return v_.ref_count();
}




} /* namespace TNT */

IMPALGEBRA_END_INTERNAL_NAMESPACE

#endif /* IMPALGEBRA_TNT_ARRAY_2D_H */