/*

Copyright (C) 1996, 1997, 2003, 2004, 2005, 2006, 2007 John W. Eaton

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/>.

*/

// Author: John W. Eaton.

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <cstring>

#include <cctype>

#include <fstream>

#include <iomanip>

#include <iostream>

#include <sstream>

#include <string>

#include "byte-swap.h"

#include "data-conv.h"

#include "file-ops.h"

#include "glob-match.h"

#include "lo-mappers.h"

#include "mach-info.h"

#include "oct-env.h"

#include "oct-time.h"

#include "quit.h"

#include "str-vec.h"

#include "Cell.h"

#include "defun.h"

#include "error.h"

#include "gripes.h"

#include "load-save.h"

#include "oct-obj.h"

#include "oct-map.h"

#include "ov-cell.h"

#include "pager.h"

#include "pt-exp.h"

#include "symtab.h"

#include "sysdep.h"

#include "unwind-prot.h"

#include "utils.h"

#include "variables.h"

#include "version.h"

#include "dMatrix.h"

#include "ls-oct-ascii.h"

// The number of decimal digits to use when writing ascii data.

static int Vsave_precision = 16;

// Functions for reading ascii data.

// Extract a KEYWORD and its value from stream IS, returning the

// associated value in a new string.

//

// Input should look something like:

//

//  [%#][ \t]*keyword[ \t]*:[ \t]*string-value[ \t]*\n

std::string

extract_keyword (std::istream& is, const char *keyword, const bool next_only)

{

  std::string retval;

  char c;

  while (is.get (c))

    {

      if (c == '%' || c == '#')

	{

	  std::ostringstream buf;

	  while (is.get (c) && (c == ' ' || c == '\t' || c == '%' || c == '#'))

	    ; // Skip whitespace and comment characters.

	  if (isalpha (c))

	    buf << c;

	  while (is.get (c) && isalpha (c))

	    buf << c;

	  std::string tmp = buf.str ();

	  bool match = (tmp.compare (0, strlen (keyword), keyword) == 0);

	  if (match)

	    {

	      std::ostringstream value;

	      while (is.get (c) && (c == ' ' || c == '\t' || c == ':'))

		; // Skip whitespace and the colon.

	      is.putback(c);

	      retval = read_until_newline (is, false);

	      break;

	    }

	  else if (next_only)

	    break;

	  else

	    {

	      while (is.get (c) && c != '\n' && c != '\r')

		; // Skip to end of line.

	    }

	}

    }

  int len = retval.length ();

  if (len > 0)

    {

      while (len)

	{

	  c = retval[len-1];

	  if (c == ' ' || c == '\t')

	    len--;

	  else

	    {

	      retval.resize (len);

	      break;

	    }

	}

    }

  return retval;

}

// Extract one value (scalar, matrix, string, etc.) from stream IS and

// place it in TC, returning the name of the variable.  If the value

// is tagged as global in the file, return TRUE in GLOBAL.

//

// Each type supplies its own function to load the data, and so this

// function is extensible.

//

// FILENAME is used for error messages.

//

// The data is expected to be in the following format:

//

// The input file must have a header followed by some data.

//

// All lines in the header must begin with a `#' character.

//

// The header must contain a list of keyword and value pairs with the

// keyword and value separated by a colon.

//

// Keywords must appear in the following order:

//

// # name: <name>

// # type: <type>

// # <info>

//

// Where, for the built in types are:

//

//  <name> : a valid identifier

//

//  <type> : <typename>

//         | global <typename>

//

//  <typename> : scalar

//             | complex scalar

//             | matrix

//             | complex matrix

//             | bool

//             | bool matrix

//             | string

//             | range

//

//  <info> : <matrix info>

//         | <string info>

//

//  <matrix info> : # rows: <integer>

//                : # columns: <integer>

//

//  <string info> : # elements: <integer>

//                : # length: <integer> (once before each string)

//

//  For backward compatibility the type "string array" is treated as a

// "string" type. Also "string" can have a single element with no elements

// line such that

//

//  <string info> : # length: <integer>

//

// Formatted ASCII data follows the header.

//

// Example:

//

//  # name: foo

//  # type: matrix

//  # rows: 2

//  # columns: 2

//    2  4

//    1  3

//

// Example:

//

//  # name: foo

//  # type: string

//  # elements: 5

//  # length: 4

//  this

//  # length: 2

//  is

//  # length: 1

//  a

//  # length: 6

//  string

//  # length: 5

//  array

//

// FIXME -- this format is fairly rigid, and doesn't allow for

// arbitrary comments.  Someone should fix that. It does allow arbitrary

// types however.

// Ugh.  The signature of the compare method is not standard in older

// versions of the GNU libstdc++.  Do this instead:

#define SUBSTRING_COMPARE_EQ(s, pos, n, t) (s.substr (pos, n) == t)

std::string

read_ascii_data (std::istream& is, const std::string& filename, bool& global,

		 octave_value& tc, octave_idx_type count)

{

  // Read name for this entry or break on EOF.

  std::string name = extract_keyword (is, "name");

  if (name.empty ())

    {

      if (count == 0)

	error ("load: empty name keyword or no data found in file `%s'",

	       filename.c_str ());

      return std::string ();

    }

  if (name == CELL_ELT_TAG)

    {

      // This is OK -- name won't be used.

    }

  else if (! valid_identifier (name))

    {

      error ("load: bogus identifier `%s' found in file `%s'",

	     name.c_str (), filename.c_str ());

      return std::string ();

    }

  // Look for type keyword.

  std::string tag = extract_keyword (is, "type");

  if (! tag.empty ())

    {

      std::string typ;

      size_t pos = tag.rfind (' ');

      if (pos != NPOS)

	{

	  global = SUBSTRING_COMPARE_EQ (tag, 0, 6, "global");

	  typ = global ? tag.substr (7) : tag;

	}

      else

	typ = tag;

      // Special case for backward compatiablity. A small bit of cruft

      if (SUBSTRING_COMPARE_EQ (typ, 0, 12, "string array"))

	tc = octave_value (charMatrix (), true);

      else

	tc = octave_value_typeinfo::lookup_type (typ);

      if (! tc.load_ascii (is))

	error ("load: trouble reading ascii file `%s'", filename.c_str ());

    }

  else

    error ("load: failed to extract keyword specifying value type");

  if (error_state)

    {

      error ("load: reading file %s", filename.c_str ());

      return std::string ();

    }

  return name;

}

// Save the data from TC along with the corresponding NAME, and global

// flag MARK_AS_GLOBAL on stream OS in the plain text format described

// above for load_ascii_data.  If NAME is empty, the name: line is not

// generated.  PRECISION specifies the number of decimal digits to print. 

//

// Assumes ranges and strings cannot contain Inf or NaN values.

//

// Returns 1 for success and 0 for failure.

// FIXME -- should probably write the help string here too.

bool

save_ascii_data (std::ostream& os, const octave_value& val_arg,

		 const std::string& name, bool mark_as_global,

		 int precision)

{

  bool success = true;

  if (! name.empty ())

    os << "# name: " << name << "\n";

  octave_value val = val_arg;

  if (mark_as_global)

    os << "# type: global " << val.type_name () << "\n";

  else

    os << "# type: " << val.type_name() << "\n";

  if (! precision)

    precision = Vsave_precision;

  long old_precision = os.precision ();

  os.precision (precision);

  success = val.save_ascii (os);

  os.precision (old_precision);

  return (os && success);

}

bool

save_ascii_data_for_plotting (std::ostream& os, const octave_value& t,

			      const std::string& name)

{

  return save_ascii_data (os, t, name, false, 6);

}

// Maybe this should be a static function in tree-plot.cc?

// If TC is matrix, save it on stream OS in a format useful for

// making a 3-dimensional plot with gnuplot.  If PARAMETRIC is

// TRUE, assume a parametric 3-dimensional plot will be generated.

bool

save_three_d (std::ostream& os, const octave_value& tc, bool parametric)

{

  bool fail = false;

  octave_idx_type nr = tc.rows ();

  octave_idx_type nc = tc.columns ();

  if (tc.is_real_matrix ())

    {

      os << "# 3D data...\n"

	 << "# type: matrix\n"

	 << "# total rows: " << nr << "\n"

	 << "# total columns: " << nc << "\n";

      long old_precision = os.precision ();

      os.precision (6);

      if (parametric)

	{

	  octave_idx_type extras = nc % 3;

	  if (extras)

	    warning ("ignoring last %d columns", extras);

	  Matrix tmp = tc.matrix_value ();

	  nr = tmp.rows ();

	  for (octave_idx_type i = 0; i < nc-extras; i += 3)

	    {

	      os << tmp.extract (0, i, nr-1, i+2);

	      if (i+3 < nc-extras)

		os << "\n";

	    }

	}

      else

	{

	  Matrix tmp = tc.matrix_value ();

	  nr = tmp.rows ();

	  for (octave_idx_type i = 0; i < nc; i++)

	    {

	      os << tmp.extract (0, i, nr-1, i);

	      if (i+1 < nc)

		os << "\n";

	    }

	}

      os.precision (old_precision);

    }

  else

    {

      ::error ("for now, I can only save real matrices in 3D format");

      fail = true;

    }

  return (os && ! fail);

}

DEFUN (save_precision, args, nargout,

    "-*- texinfo -*-\n\

@deftypefn {Built-in Function} {@var{val} =} save_precision ()\n\

@deftypefnx {Built-in Function} {@var{old_val} =} save_precision (@var{new_val})\n\

Query or set the internal variable that specifies the number of\n\

digits to keep when saving data in text format.\n\

@end deftypefn")

{

  return SET_INTERNAL_VARIABLE_WITH_LIMITS (save_precision, -1, INT_MAX);

}

/*

;;; Local Variables: ***

;;; mode: C++ ***

;;; End: ***

*/