/*

Copyright (C) 2004, 2005, 2006, 2007 David Bateman

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/>.

In addition to the terms of the GPL, you are permitted to link
this program with any Open Source program, as defined by the
Open Source Initiative (www.opensource.org)

*/

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

#include <istream>
#include <iostream>
#include <sstream>
#include <vector>

#include "oct-locbuf.h"

#include "defun.h"
#include "error.h"
#include "gripes.h"
#include "oct-map.h"
#include "ov-base.h"
#include "ov-fcn-inline.h"
#include "ov-usr-fcn.h"
#include "pr-output.h"
#include "variables.h"
#include "parse.h"
#include "toplev.h"

#include "byte-swap.h"
#include "ls-oct-ascii.h"
#include "ls-hdf5.h"
#include "ls-utils.h"

DEFINE_OCTAVE_ALLOCATOR (octave_fcn_inline);

DEFINE_OV_TYPEID_FUNCTIONS_AND_DATA (octave_fcn_inline,
				     "inline function",
				     "function_handle");

octave_fcn_inline::octave_fcn_inline (const std::string& f,
				      const string_vector& a,
				      const std::string& n)
  : octave_fcn_handle (n), iftext (f), ifargs (a)
{
  // Form a string representing the function.

  std::ostringstream buf;

  buf << "@(";

  for (int i = 0; i < ifargs.length (); i++)
    {
      if (i > 0)
	buf << ", ";

      buf << ifargs(i);
    }

  buf << ") " << iftext;

  int parse_status;
  octave_value anon_fcn_handle = eval_string (buf.str (), true, parse_status);

  if (parse_status == 0)
    {
      octave_fcn_handle *fh = anon_fcn_handle.fcn_handle_value ();

      if (fh)
	{
	  fcn = fh->fcn_val ();

	  octave_user_function *uf = fcn.user_function_value ();

	  if (uf)
	    {
	      octave_function *curr_fcn = octave_call_stack::current ();

	      if (curr_fcn)
		{
		  symbol_table::scope_id parent_scope
		    = curr_fcn->parent_fcn_scope ();

		  if (parent_scope < 0)
		    parent_scope = curr_fcn->scope ();
	
		  uf->stash_parent_fcn_scope (parent_scope);
		}
	    }
	}
    }

  if (fcn.is_undefined ())
    error ("inline: unable to define function");
}

// This function is supplied to allow a Matlab style class structure
// to be returned..
Octave_map
octave_fcn_inline::map_value (void) const
{
  Octave_map m;
  string_vector args = fcn_arg_names ();
  m.assign ("version", octave_value (1.0));
  m.assign ("isEmpty", octave_value (0.0));
  m.assign ("expr", octave_value (fcn_text ()));
  m.assign ("numArgs", octave_value (args.length ()));
  m.assign ("args", octave_value (args));
  std::ostringstream buf;
  for (int i = 0; i < args.length (); i++)
    buf << args(i) << " = INLINE_INPUTS_{" << i + 1 << "}; ";
  m.assign ("inputExpr", octave_value (buf.str ()));

  return m;
}

bool
octave_fcn_inline::save_ascii (std::ostream& os)
{
  os << "# nargs: " <<  ifargs.length () << "\n";
  for (int i = 0; i < ifargs.length (); i++)
    os << ifargs(i) << "\n";
  if (nm.length () < 1)
    // Write an invalid value to flag empty fcn handle name.
    os << "0\n";
  else
    os << nm << "\n";
  os << iftext << "\n";
  return true;
}

bool
octave_fcn_inline::load_ascii (std::istream& is)
{
  int nargs;
  if (extract_keyword (is, "nargs", nargs, true))
    {
      ifargs.resize (nargs);
      for (int i = 0; i < nargs; i++)
	is >> ifargs(i);
      is >> nm;
      if (nm == "0")
	nm = "";

      char c;
      std::ostringstream buf;

      // Skip preceeding newline(s)
      while (is.get (c) && c == '\n')
	/* do nothing */;

      if (is)
	{
	  buf << c;

	  // Get a line of text whitespace characters included, leaving
	  // newline in the stream
	  while (is.peek () != '\n')
	    {
	      is.get (c);
	      if (! is)
		break;
	      buf << c;
	    }
	}

      iftext = buf.str ();

      octave_fcn_inline tmp (iftext, ifargs, nm);
      fcn = tmp.fcn;

      return true;
    }
  else
    return false;
}

bool
octave_fcn_inline::save_binary (std::ostream& os, bool&)
{
  int32_t tmp = ifargs.length ();
  os.write (reinterpret_cast<char *> (&tmp), 4);
  for (int i = 0; i < ifargs.length (); i++)
    {
      tmp = ifargs(i).length ();
      os.write (reinterpret_cast<char *> (&tmp), 4);
      os.write (ifargs(i).c_str (), ifargs(i).length ());
    }
  tmp = nm.length ();
  os.write (reinterpret_cast<char *> (&tmp), 4);
  os.write (nm.c_str (), nm.length ());
  tmp = iftext.length ();
  os.write (reinterpret_cast<char *> (&tmp), 4);
  os.write (iftext.c_str (), iftext.length ());
  return true;
}

bool
octave_fcn_inline::load_binary (std::istream& is, bool swap,
				oct_mach_info::float_format)
{
  int32_t nargs;
  if (! is.read (reinterpret_cast<char *> (&nargs), 4))
    return false;
  if (swap)
    swap_bytes<4> (&nargs);

  if (nargs < 1)
    return false;
  else
    {
      int32_t tmp;
      ifargs.resize (nargs);
      for (int i = 0; i < nargs; i++)
	{
	  if (! is.read (reinterpret_cast<char *> (&tmp), 4))
	    return false;
	  if (swap)
	    swap_bytes<4> (&tmp);

	  OCTAVE_LOCAL_BUFFER (char, ctmp, tmp+1);
	  is.read (ctmp, tmp);
	  ifargs(i) = std::string (ctmp);

	  if (! is)
	    return false;
	}

      if (! is.read (reinterpret_cast<char *> (&tmp), 4))
	return false;
      if (swap)
	swap_bytes<4> (&tmp);

      OCTAVE_LOCAL_BUFFER (char, ctmp1, tmp+1);
      is.read (ctmp1, tmp);
      nm = std::string (ctmp1);

      if (! is)
	return false;

      if (! is.read (reinterpret_cast<char *> (&tmp), 4))
	return false;
      if (swap)
	swap_bytes<4> (&tmp);

      OCTAVE_LOCAL_BUFFER (char, ctmp2, tmp+1);
      is.read (ctmp2, tmp);
      iftext = std::string (ctmp2);

      if (! is)
	return false;

      octave_fcn_inline ftmp (iftext, ifargs, nm);
      fcn = ftmp.fcn;
    }
  return true;
}

#if defined (HAVE_HDF5)
bool
octave_fcn_inline::save_hdf5 (hid_t loc_id, const char *name,
			      bool /* save_as_floats */)
{
  hid_t group_hid = -1;
  group_hid = H5Gcreate (loc_id, name, 0);
  if (group_hid < 0 ) return false;

  size_t len = 0;
  for (int i = 0; i < ifargs.length (); i++)
    if (len < ifargs(i).length ())
      len = ifargs(i).length ();

  hid_t space_hid = -1, data_hid = -1, type_hid = -1;;
  bool retval = true;

  // FIXME Is there a better way of saving string vectors, than a
  // null padded matrix?

  OCTAVE_LOCAL_BUFFER (hsize_t, hdims, 2);

  // Octave uses column-major, while HDF5 uses row-major ordering
  hdims[1] = ifargs.length ();
  hdims[0] = len + 1;

  space_hid = H5Screate_simple (2, hdims, 0);
  if (space_hid < 0)
    {
      H5Gclose (group_hid);
      return false;
    }

  data_hid = H5Dcreate (group_hid, "args", H5T_NATIVE_CHAR, space_hid,
			H5P_DEFAULT);
  if (data_hid < 0)
    {
      H5Sclose (space_hid);
      H5Gclose (group_hid);
      return false;
    }

  OCTAVE_LOCAL_BUFFER (char, s, ifargs.length () * (len + 1));

  // Save the args as a null teminated list
  for (int i = 0; i < ifargs.length (); i++)
    {
      const char * cptr = ifargs(i).c_str ();
      for (size_t j = 0; j < ifargs(i).length (); j++)
	s[i*(len+1)+j] = *cptr++;
      s[ifargs(i).length ()] = '\0';
    }

  retval = H5Dwrite (data_hid, H5T_NATIVE_CHAR, H5S_ALL, H5S_ALL,
		     H5P_DEFAULT, s) >= 0;

  H5Dclose (data_hid);
  H5Sclose (space_hid);

  if (!retval)
    {
      H5Gclose (group_hid);
      return false;
    }

  // attach the type of the variable
  type_hid = H5Tcopy (H5T_C_S1);
  H5Tset_size (type_hid, nm.length () + 1);
  if (type_hid < 0)
    {
      H5Gclose (group_hid);
      return false;
    }

  hdims[0] = 0;
  space_hid = H5Screate_simple (0 , hdims, 0);
  if (space_hid < 0)
    {
      H5Tclose (type_hid);
      H5Gclose (group_hid);
      return false;
    }

  data_hid = H5Dcreate (group_hid, "nm",  type_hid, space_hid, H5P_DEFAULT);
  if (data_hid < 0 || H5Dwrite (data_hid, type_hid, H5S_ALL, H5S_ALL,
				H5P_DEFAULT, nm.c_str ()) < 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Gclose (group_hid);
      return false;
    }
  H5Dclose (data_hid);

  // attach the type of the variable
  H5Tset_size (type_hid, iftext.length () + 1);
  if (type_hid < 0)
    {
      H5Gclose (group_hid);
      return false;
    }

  data_hid = H5Dcreate (group_hid, "iftext",  type_hid, space_hid,
			H5P_DEFAULT);
  if (data_hid < 0 || H5Dwrite (data_hid, type_hid, H5S_ALL, H5S_ALL,
				H5P_DEFAULT, iftext.c_str ()) < 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Gclose (group_hid);
      return false;
    }

  H5Dclose (data_hid);
  H5Sclose (space_hid);
  H5Tclose (type_hid);
  H5Gclose (group_hid);

  return retval;
}

bool
octave_fcn_inline::load_hdf5 (hid_t loc_id, const char *name,
			      bool /* have_h5giterate_bug */)
{
  hid_t group_hid, data_hid, space_hid, type_hid, type_class_hid, st_id;
  hsize_t rank;
  int slen;

  group_hid = H5Gopen (loc_id, name);
  if (group_hid < 0 ) return false;

  data_hid = H5Dopen (group_hid, "args");
  space_hid = H5Dget_space (data_hid);
  rank = H5Sget_simple_extent_ndims (space_hid);

  if (rank != 2)
    {
      H5Dclose (data_hid);
      H5Sclose (space_hid);
      H5Gclose (group_hid);
      return false;
    }

  OCTAVE_LOCAL_BUFFER (hsize_t, hdims, rank);
  OCTAVE_LOCAL_BUFFER (hsize_t, maxdims, rank);

  H5Sget_simple_extent_dims (space_hid, hdims, maxdims);

  ifargs.resize (hdims[1]);

  OCTAVE_LOCAL_BUFFER (char, s1, hdims[0] * hdims[1]);

  if (H5Dread (data_hid, H5T_NATIVE_UCHAR, H5S_ALL, H5S_ALL,
	       H5P_DEFAULT, s1) < 0)
    {
      H5Dclose (data_hid);
      H5Sclose (space_hid);
      H5Gclose (group_hid);
      return false;
    }

  H5Dclose (data_hid);
  H5Sclose (space_hid);

  for (size_t i = 0; i < hdims[1]; i++)
    ifargs(i) = std::string (s1 + i*hdims[0]);

  data_hid = H5Dopen (group_hid, "nm");

  if (data_hid < 0)
    {
      H5Gclose (group_hid);
      return false;
    }

  type_hid = H5Dget_type (data_hid);
  type_class_hid = H5Tget_class (type_hid);

  if (type_class_hid != H5T_STRING)
    {
      H5Tclose (type_hid);
      H5Dclose (data_hid);
      H5Gclose (group_hid);
      return false;
    }

  space_hid = H5Dget_space (data_hid);
  rank = H5Sget_simple_extent_ndims (space_hid);

  if (rank != 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Dclose (data_hid);
      H5Gclose (group_hid);
      return false;
    }

  slen = H5Tget_size (type_hid);
  if (slen < 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Dclose (data_hid);
      H5Gclose (group_hid);
      return false;
    }

  OCTAVE_LOCAL_BUFFER (char, nm_tmp, slen);

  // create datatype for (null-terminated) string to read into:
  st_id = H5Tcopy (H5T_C_S1);
  H5Tset_size (st_id, slen);

  if (H5Dread (data_hid, st_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, nm_tmp) < 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Gclose (group_hid);
      return false;
    }
  H5Tclose (st_id);
  H5Dclose (data_hid);
  nm = nm_tmp;

  data_hid = H5Dopen (group_hid, "iftext");

  if (data_hid < 0)
    {
      H5Gclose (group_hid);
      return false;
    }

  type_hid = H5Dget_type (data_hid);
  type_class_hid = H5Tget_class (type_hid);

  if (type_class_hid != H5T_STRING)
    {
      H5Tclose (type_hid);
      H5Dclose (data_hid);
      H5Gclose (group_hid);
      return false;
    }

  space_hid = H5Dget_space (data_hid);
  rank = H5Sget_simple_extent_ndims (space_hid);

  if (rank != 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Dclose (data_hid);
      H5Gclose (group_hid);
      return false;
    }

  slen = H5Tget_size (type_hid);
  if (slen < 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Dclose (data_hid);
      H5Gclose (group_hid);
      return false;
    }

  OCTAVE_LOCAL_BUFFER (char, iftext_tmp, slen);

  // create datatype for (null-terminated) string to read into:
  st_id = H5Tcopy (H5T_C_S1);
  H5Tset_size (st_id, slen);

  if (H5Dread (data_hid, st_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, iftext_tmp) < 0)
    {
      H5Sclose (space_hid);
      H5Tclose (type_hid);
      H5Gclose (group_hid);
      return false;
    }
  H5Tclose (st_id);
  H5Dclose (data_hid);
  iftext = iftext_tmp;

  octave_fcn_inline ftmp (iftext, ifargs, nm);
  fcn = ftmp.fcn;

  return true;
}
#endif

void
octave_fcn_inline::print (std::ostream& os, bool pr_as_read_syntax) const
{
  print_raw (os, pr_as_read_syntax);
  newline (os);
}

void
octave_fcn_inline::print_raw (std::ostream& os, bool pr_as_read_syntax) const
{
  std::ostringstream buf;

  if (nm.empty ())
    buf << "f(";
  else
    buf << nm << "(";

  for (int i = 0; i < ifargs.length (); i++)
    {
      if (i)
	buf << ", ";

      buf << ifargs(i);
    }

  buf << ") = " << iftext;

  octave_print_internal (os, buf.str (), pr_as_read_syntax,
			 current_print_indent_level ());
}

octave_value
octave_fcn_inline::convert_to_str_internal (bool, bool, char type) const
{
  return octave_value (fcn_text (), type);
}

DEFUNX ("inline", Finline, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} inline (@var{str})\n\
@deftypefnx {Built-in Function} {} inline (@var{str}, @var{arg1}, @dots{})\n\
@deftypefnx {Built-in Function} {} inline (@var{str}, @var{n})\n\
Create an inline function from the character string @var{str}.\n\
If called with a single argument, the arguments of the generated\n\
function are extracted from the function itself. The generated\n\
function arguments will then be in alphabetical order. It should\n\
be noted that i, and j are ignored as arguments due to the\n\
ambiguity between their use as a variable or their use as an inbuilt\n\
constant. All arguments followed by a parenthesis are considered\n\
to be functions.\n\
\n\
If the second and subsequent arguments are character strings,\n\
they are the names of the arguments of the function.\n\
\n\
If the second argument is an integer @var{n}, the arguments are\n\
@code{\"x\"}, @code{\"P1\"}, @dots{}, @code{\"P@var{N}\"}.\n\
@seealso{argnames, formula, vectorize}\n\
@end deftypefn")
{
  octave_value retval;

  int nargin = args.length ();

  if (nargin > 0)
    {
      std::string fun = args(0).string_value ();

      if (! error_state)
	{
	  string_vector fargs;

	  if (nargin == 1)
	    {
	      bool is_arg = false;
	      bool in_string = false;
	      std::string tmp_arg;
	      size_t i = 0;
	      
	      while (i < fun.length ())
		{
		  bool terminate_arg = false;
		  char c = fun[i++];

		  if (in_string)
		    {
		      if (c == '\'' || c == '\"')
			in_string = false;
		    }
		  else if (c == '\'' || c == '\"')
		    {
		      in_string = true;
		      if (is_arg)
			terminate_arg = true;
		    }
		  else if (! isalpha (c) && c != '_')
		    if (! is_arg)
		      continue;
		    else if (isdigit (c))
		      tmp_arg.append (1, c);
		    else
		      {
			// Before we do anything remove trailing whitespaces.
			while (i < fun.length () && isspace (c))
			  c = fun[i++];
			
			// Do we have a variable or a function?
			if (c != '(')
			  terminate_arg = true;
			else
			  {
			    tmp_arg = std::string ();
			    is_arg = false;
			  }
		      }
		  else
		    {
		      tmp_arg.append (1, c);
		      is_arg = true;
		    }

		  if (terminate_arg || (i == fun.length () && is_arg))
		    {
		      bool have_arg = false;
		      
		      for (int j = 0; j < fargs.length (); j++)
			if (tmp_arg == fargs (j))
			  {
			    have_arg = true;
			    break;
			  }
			  
		      if (! have_arg && tmp_arg != "i" && tmp_arg != "j" &&
			  tmp_arg != "NaN" && tmp_arg != "nan" && 
			  tmp_arg != "Inf" && tmp_arg != "inf" && 
			  tmp_arg != "NA" && tmp_arg != "pi" &&
			  tmp_arg != "eps")
			fargs.append (tmp_arg);

		      tmp_arg = std::string ();
		      is_arg = false;
		    }
		}

	      // Sort the arguments into ascii order.
	      fargs.qsort ();
	    }
	  else if (nargin == 2 && args(1).is_numeric_type ())
	    {
	      int n = args(1).int_value ();

	      if (! error_state)
		{
		  if (n >= 0)
		    {
		      fargs.resize (n+1);

		      fargs(0) = "x";

		      for (int i = 1; i < n+1; i++)
			{
			  std::ostringstream buf;
			  buf << "P" << i;
			  fargs(i) = buf.str ();
			}
		    }
		  else
		    {
		      error ("inline: numeric argument must be nonnegative");
		      return retval;
		    }
		}
	      else
		{
		  error ("inline: expecting second argument to be an integer");
		  return retval;
		}
	    }
	  else
	    {
	      fargs.resize (nargin - 1);

	      for (int i = 1; i < nargin; i++)
		{
		  std::string s = args(i).string_value ();

		  if (! error_state)
		    fargs(i-1) = s;
		  else
		    {
		      error ("inline: expecting string arguments");
		      return retval;
		    }
		}
	    }

	  retval = octave_value (new octave_fcn_inline (fun, fargs));
	}
      else
	error ("inline: first argument must be a string");
    }
  else
    print_usage ();

  return retval;
}

/*
%!shared fn
%! fn = inline ("x.^2 + 1","x");
%!assert (feval (fn, 6), 37)
%!assert (fn (6), 37)
*/

DEFUN (formula, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} formula (@var{fun})\n\
Return a character string representing the inline function @var{fun}.\n\
Note that @code{char (@var{fun})} is equivalent to\n\
@code{formula (@var{fun})}.\n\
@seealso{argnames, inline, vectorize}\n\
@end deftypefn")
{
  octave_value retval;

  int nargin = args.length ();

  if (nargin == 1)
    {
      octave_fcn_inline* fn = args(0).fcn_inline_value (true);

      if (fn)
	retval = octave_value (fn->fcn_text ());
      else
	error ("formula: must be an inline function");
    }
  else
    print_usage ();

  return retval;
}

DEFUN (argnames, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} argnames (@var{fun})\n\
Return a cell array of character strings containing the names of\n\
the arguments of the inline function @var{fun}.\n\
@seealso{inline, formula, vectorize}\n\
@end deftypefn")
{
  octave_value retval;

  int nargin = args.length ();

  if (nargin == 1)
    {
      octave_fcn_inline *fn = args(0).fcn_inline_value (true);

      if (fn)
	{
	  string_vector t1 = fn->fcn_arg_names ();

	  Cell t2 (dim_vector (t1.length (), 1));

	  for (int i = 0; i < t1.length (); i++)
	    t2(i) = t1(i);

	  retval = t2;
	}
      else
	error ("argnames: argument must be an inline function");
    }
  else
    print_usage ();

  return retval;
}

DEFUN (vectorize, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Built-in Function} {} vectorize (@var{fun})\n\
Create a vectorized version of the inline function @var{fun}\n\
by replacing all occurrences of @code{*}, @code{/}, etc., with\n\
@code{.*}, @code{./}, etc.\n\
@end deftypefn")
{
  octave_value retval;

  int nargin = args.length ();

  if (nargin == 1)
    {
      std::string old_func;
      octave_fcn_inline* old = 0;
      bool func_is_string = true;

      if (args(0).is_string ())
	old_func = args(0).string_value ();
      else
	{
	  old = args(0).fcn_inline_value (true);
	  func_is_string = false;

	  if (old)
	    old_func = old->fcn_text ();
	  else
	    error ("vectorize: must be a string or inline function");
	}

      if (! error_state)
	{
	  std::string new_func;
	  size_t i = 0;

	  while (i < old_func.length ())
	    {
	      std::string t1 = old_func.substr (i, 1);

	      if (t1 == "*" || t1 == "/" || t1 == "\\" || t1 == "^")
		{
		  if (i && old_func.substr (i-1, 1) != ".")
		    new_func.append (".");

		  // Special case for ** operator.
		  if (t1 == "*" && i < (old_func.length () - 1)
		      && old_func.substr (i+1, 1) == "*")
		    {
		      new_func.append ("*");
		      i++;
		    }
		}
	      new_func.append (t1);
	      i++;
	    }

	  if (func_is_string)
	    retval = octave_value (new_func);
	  else
	    retval = octave_value (new octave_fcn_inline 
				   (new_func, old->fcn_arg_names ()));
	}
    }
  else
    print_usage ();

  return retval;
}

/*
;;; Local Variables: ***
;;; mode: C++ ***
;;; End: ***
*/