/*

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/>.

*/

#if defined (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";

namespace octave
{
  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 (OCTAVE_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.ndims ())   // 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 */