////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 1996-2020 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if ! defined (octave_ov_base_scalar_h)
#define octave_ov_base_scalar_h 1

#include "octave-config.h"

#include <cstdlib>

#include <iosfwd>
#include <string>

#include "lo-mappers.h"
#include "lo-utils.h"
#include "str-vec.h"
#include "MatrixType.h"

#include "ov-base.h"
#include "ov-typeinfo.h"

// Real scalar values.

template <typename ST>
class
octave_base_scalar : public octave_base_value
{
public:

  typedef ST scalar_type;

  octave_base_scalar (void)
    : octave_base_value (), scalar () { }

  octave_base_scalar (const ST& s)
    : octave_base_value (), scalar (s) { }

  octave_base_scalar (const octave_base_scalar& s)
    : octave_base_value (), scalar (s.scalar) { }

  ~octave_base_scalar (void) = default;

  octave_value squeeze (void) const { return scalar; }

  octave_value full_value (void) const { return scalar; }

  // We don't need to override all three forms of subsref.  The using
  // declaration will avoid warnings about partially-overloaded virtual
  // functions.
  using octave_base_value::subsref;

  octave_value subsref (const std::string& type,
                        const std::list<octave_value_list>& idx);

  octave_value_list subsref (const std::string& type,
                             const std::list<octave_value_list>& idx, int)
  { return subsref (type, idx); }

  octave_value subsasgn (const std::string& type,
                         const std::list<octave_value_list>& idx,
                         const octave_value& rhs);

  bool is_constant (void) const { return true; }

  bool is_defined (void) const { return true; }

  dim_vector dims (void) const;

  octave_idx_type numel (void) const { return 1; }

  int ndims (void) const { return 2; }

  octave_idx_type nnz (void) const { return (scalar != ST () ? 1 : 0); }

  octave_value permute (const Array<int>&, bool = false) const;

  octave_value reshape (const dim_vector& new_dims) const;

  size_t byte_size (void) const { return sizeof (ST); }

  octave_value all (int = 0) const { return (scalar != ST ()); }

  octave_value any (int = 0) const { return (scalar != ST ()); }

  octave_value diag (octave_idx_type k = 0) const;

  octave_value diag (octave_idx_type m, octave_idx_type n) const;

  octave_value sort (octave_idx_type, sortmode) const
  { return octave_value (scalar); }
  octave_value sort (Array<octave_idx_type> &sidx, octave_idx_type,
                     sortmode) const
  {
    sidx.resize (dim_vector (1, 1));
    sidx(0) = 0;
    return octave_value (scalar);
  }

  sortmode issorted (sortmode mode = UNSORTED) const
  { return mode == UNSORTED ? ASCENDING : mode; }

  Array<octave_idx_type> sort_rows_idx (sortmode) const
  {
    return Array<octave_idx_type> (dim_vector (1, 1),
                                   static_cast<octave_idx_type> (0));
  }

  sortmode is_sorted_rows (sortmode mode = UNSORTED) const
  { return mode == UNSORTED ? ASCENDING : mode; }

  MatrixType matrix_type (void) const { return MatrixType::Diagonal; }
  MatrixType matrix_type (const MatrixType&) const
  { return matrix_type (); }

  bool is_scalar_type (void) const { return true; }

  bool isnumeric (void) const { return true; }

  bool is_true (void) const;

  void print (std::ostream& os, bool pr_as_read_syntax = false);

  void print_raw (std::ostream& os, bool pr_as_read_syntax = false) const;

  bool print_name_tag (std::ostream& os, const std::string& name) const;

  void short_disp (std::ostream& os) const;

  float_display_format get_edit_display_format (void) const;

  std::string edit_display (const float_display_format& fmt,
                            octave_idx_type i, octave_idx_type j) const;

  // Unsafe.  This function exists to support the MEX interface.
  // You should not use it anywhere else.
  void * mex_get_data (void) const { return const_cast<ST *> (&scalar); }

  const ST& scalar_ref (void) const { return scalar; }

  ST& scalar_ref (void) { return scalar; }

  octave_value fast_elem_extract (octave_idx_type n) const;

  bool fast_elem_insert_self (void *where, builtin_type_t btyp) const;

protected:

  // The value of this scalar.
  ST scalar;
};

#endif