/*

Copyright (C) 2016 Rik Wehbring

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
<http://www.gnu.org/licenses/>.

*/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <sstream>

#include "lo-array-errwarn.h"
#include "lo-error.h"

// Text constants used to shorten code below.
static const char *error_id_nonconformant_args = "Octave:nonconformant-args";

static const char *error_id_index_out_of_bounds = "Octave:index-out-of-bounds";

static const char *error_id_invalid_index = "Octave:invalid-index";

static const char *warning_id_nearly_singular_matrix = "Octave:nearly-singular-matrix";

static const char *warning_id_singular_matrix = "Octave:singular-matrix";

void
err_nan_to_logical_conversion (void)
{
  (*current_liboctave_error_handler)
    ("invalid conversion from NaN to logical");
}

void
err_nan_to_character_conversion (void)
{
  (*current_liboctave_error_handler)
    ("invalid conversion from NaN to character");
}

void
err_nonconformant (const char *op,
                   octave_idx_type op1_len, octave_idx_type op2_len)
{
  const char *err_id = error_id_nonconformant_args;

  (*current_liboctave_error_with_id_handler)
    (err_id, "%s: nonconformant arguments (op1 len: %d, op2 len: %d)",
     op, op1_len, op2_len);
}

void
err_nonconformant (const char *op,
                   octave_idx_type op1_nr, octave_idx_type op1_nc,
                   octave_idx_type op2_nr, octave_idx_type op2_nc)
{
  const char *err_id = error_id_nonconformant_args;

  (*current_liboctave_error_with_id_handler)
    (err_id, "%s: nonconformant arguments (op1 is %dx%d, op2 is %dx%d)",
     op, op1_nr, op1_nc, op2_nr, op2_nc);
}

void
err_nonconformant (const char *op,
                   const dim_vector& op1_dims, const dim_vector& op2_dims)
{
  const char *err_id = error_id_nonconformant_args;

  std::string op1_dims_str = op1_dims.str ();
  std::string op2_dims_str = op2_dims.str ();

  (*current_liboctave_error_with_id_handler)
    (err_id, "%s: nonconformant arguments (op1 is %s, op2 is %s)",
     op, op1_dims_str.c_str (), op2_dims_str.c_str ());
}

void
err_del_index_out_of_range (bool is1d, octave_idx_type idx,
                            octave_idx_type ext)
{
  const char *err_id = error_id_index_out_of_bounds;

  (*current_liboctave_error_with_id_handler)
    (err_id, "A(%s) = []: index out of bounds: value %d out of bound %d",
     is1d ? "I" : "..,I,..", idx, ext);
}

// Common procedures of base class index_exception, thrown whenever an
// object is indexed incorrectly, such as by an index that is out of
// range, negative, fractional, complex, or of a non-numeric type.

std::string
index_exception::message (void) const
{
  std::string msg = expression () + ": " + details ();
  return msg.c_str ();
}

// Show the expression that caused the error, e.g.,  "A(-1,_)",
// "A(0+1i)", "A(_,3)".  Show how many indices come before/after the
// offending one, e.g., (<error>), (<error>,_), or (_,<error>,...[x5]...)

std::string
index_exception::expression (void) const
{
  std::ostringstream buf;

  if (var.empty () || var == "<unknown>")
    buf << "index ";
  else
    buf << var;

  bool show_parens = dim > 0;

  if (show_parens)
    {
      if (dim < 5)
        {
          buf << "(";

          for (octave_idx_type i = 1; i < dim; i++)
            buf << "_,";
        }
      else
        buf << "(...[x" << dim - 1 << "]...";
    }

  buf << idx ();

  if (show_parens)
    {
      if (nd - dim < 5)
        {
          for (octave_idx_type i = 0; i < nd - dim; i++)
            buf << ",_";

          if (nd >= dim)
            buf << ")";
        }
      else
        buf << "...[x" << nd - dim << "]...)";
    }

  return buf.str ();
}

class invalid_index : public index_exception
{
public:

  invalid_index (const std::string& value, octave_idx_type ndim,
                 octave_idx_type dimen)
    : index_exception (value, ndim, dimen)
  { }

  std::string details (void) const
  {
#if defined (ENABLE_64)
    return "subscripts must be either integers 1 to (2^63)-1 or logicals";
#else
    return "subscripts must be either integers 1 to (2^31)-1 or logicals";
#endif
  }

  // ID of error to throw
  const char *err_id (void) const
  {
    return error_id_invalid_index;
  }
};

// Complain if an index is negative, fractional, or too big.

void
err_invalid_index (const std::string& idx, octave_idx_type nd,
                   octave_idx_type dim, const std::string&)
{
  invalid_index e (idx, nd, dim);

  throw e;
}

void
err_invalid_index (octave_idx_type n, octave_idx_type nd,
                   octave_idx_type dim, const std::string& var)
{
  std::ostringstream buf;
  buf << n + 1;
  err_invalid_index (buf.str (), nd, dim, var);
}

void
err_invalid_index (double n, octave_idx_type nd, octave_idx_type dim,
                   const std::string& var)
{
  std::ostringstream buf;
  buf << n + 1;
  err_invalid_index (buf.str (), nd, dim, var);
}


// Complain for read access beyond the bounds of an array.

class out_of_range : public index_exception
{
public:

  out_of_range (const std::string& value, octave_idx_type nd_in,
                octave_idx_type dim_in)
    : index_exception (value, nd_in, dim_in), extent (0)
  { }

  std::string details (void) const
  {
    std::string expl;

    if (nd >= size.length ())   // if not an index slice
      {
        if (var != "")
          expl = "but " + var + " has size ";
        else
          expl = "but object has size ";

        expl = expl + size.str ('x');
      }
    else
      {
        std::ostringstream buf;
        buf << extent;
        expl = "out of bound " + buf.str ();
      }

    return expl;
  }

  // ID of error to throw.
  const char *err_id (void) const
  {
    return error_id_index_out_of_bounds;
  }

  void set_size (const dim_vector& size_in) { size = size_in; }

  void set_extent (octave_idx_type ext) { extent = ext; }

private:

  // Dimension of object being accessed.
  dim_vector size;

  // Length of dimension being accessed.
  octave_idx_type extent;
};

// Complain of an index that is out of range, but we don't know matrix size
void
err_index_out_of_range (int nd, int dim, octave_idx_type idx,
                        octave_idx_type ext)
{
  std::ostringstream buf;
  buf << idx;
  out_of_range e (buf.str (), nd, dim);

  e.set_extent (ext);
  // ??? Make details method give extent not size.
  e.set_size (dim_vector (1, 1, 1, 1, 1, 1,1));

  throw e;
}

// Complain of an index that is out of range
void
err_index_out_of_range (int nd, int dim, octave_idx_type idx,
                        octave_idx_type ext, const dim_vector& d)
{
  std::ostringstream buf;
  buf << idx;
  out_of_range e (buf.str (), nd, dim);

  e.set_extent (ext);
  e.set_size (d);

  throw e;
}

void
err_invalid_resize (void)
{
  (*current_liboctave_error_with_id_handler)
    ("Octave:invalid-resize",
     "Invalid resizing operation or ambiguous assignment to an out-of-bounds array element");
}

void
warn_singular_matrix (double rcond)
{
  if (rcond == 0.0)
    {
      (*current_liboctave_warning_with_id_handler)
        (warning_id_singular_matrix,
         "matrix singular to machine precision");
    }
  else
    {
      (*current_liboctave_warning_with_id_handler)
        (warning_id_nearly_singular_matrix,
         "matrix singular to machine precision, rcond = %g", rcond);
    }
}

/* Tests in test/index.tst */