/*

Copyright (C) 1996-2012 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/>.

*/

#if !defined (octave_tree_decl_h)
#define octave_tree_decl_h 1

class tree_expression;
class tree_identifier;

class tree_walker;

#include <string>

#include "base-list.h"
#include "oct-lvalue.h"
#include "pt-cmd.h"
#include "pt-id.h"
#include "symtab.h"

// List of expressions that make up a declaration statement.

class
tree_decl_elt
{
public:

  tree_decl_elt (tree_identifier *i = 0, tree_expression *e = 0)
    : id (i), expr (e) { }

  ~tree_decl_elt (void);

  bool eval (void);

  bool is_defined (void) { return id ? id->is_defined () : false; }

  bool is_variable (void) { return id ? id->is_variable () : false; }

  void mark_as_formal_parameter (void)
  {
    if (id)
      id->mark_as_formal_parameter ();
  }

  bool lvalue_ok (void) { return id ? id->lvalue_ok () : false; }

  // Do not allow functions to return null values.
  octave_value rvalue1 (int nargout = 1)
  {
    return id ? id->rvalue1 (nargout).storable_value () : octave_value ();
  }

  octave_value_list rvalue (int nargout)
  {
    octave_value_list retval;

    if (nargout > 1)
      error ("invalid number of output arguments in declaration list");
    else
      retval = rvalue1 (nargout);

    return retval;
  }

  octave_lvalue lvalue (void) { return id ? id->lvalue () : octave_lvalue (); }

  tree_identifier *ident (void) { return id; }

  tree_expression *expression (void) { return expr; }

  tree_decl_elt *dup (symbol_table::scope_id scope,
                      symbol_table::context_id context) const;

  void accept (tree_walker& tw);

private:

  // An identifier to tag with the declared property.
  tree_identifier *id;

  // An initializer expression (may be zero);
  tree_expression *expr;

  // No copying!

  tree_decl_elt (const tree_decl_elt&);

  tree_decl_elt& operator = (const tree_decl_elt&);
};

class
tree_decl_init_list : public octave_base_list<tree_decl_elt *>
{
public:

  tree_decl_init_list (void) { }

  tree_decl_init_list (tree_decl_elt *t) { append (t); }

  ~tree_decl_init_list (void)
    {
      while (! empty ())
        {
          iterator p = begin ();
          delete *p;
          erase (p);
        }
    }

  tree_decl_init_list *dup (symbol_table::scope_id scope,
                            symbol_table::context_id context) const;

  void accept (tree_walker& tw);

private:

  // No copying!

  tree_decl_init_list (const tree_decl_init_list&);

  tree_decl_init_list& operator = (const tree_decl_init_list&);
};

// Base class for declaration commands -- global, static, etc.

class
tree_decl_command : public tree_command
{
public:

  tree_decl_command (const std::string& n, int l = -1, int c = -1)
    : tree_command (l, c), cmd_name (n), init_list (0) { }

  tree_decl_command (const std::string& n, tree_decl_init_list *t,
                     int l = -1, int c = -1)
    : tree_command (l, c), cmd_name (n), init_list (t) { }

  ~tree_decl_command (void);

  tree_decl_init_list *initializer_list (void) { return init_list; }

  std::string name (void) { return cmd_name; }

protected:

  // The name of this command -- global, static, etc.
  std::string cmd_name;

  // The list of variables or initializers in this declaration command.
  tree_decl_init_list *init_list;

private:

  // No copying!

  tree_decl_command (const tree_decl_command&);

  tree_decl_command& operator = (const tree_decl_command&);
};

// Global.

class
tree_global_command : public tree_decl_command
{
public:

  tree_global_command (int l = -1, int c = -1)
    : tree_decl_command ("global", l, c) { }

  tree_global_command (tree_decl_init_list *t, int l = -1, int c = -1)
    : tree_decl_command ("global", t, l, c) { }

  ~tree_global_command (void) { }

  tree_command *dup (symbol_table::scope_id scope,
                     symbol_table::context_id context) const;

  void accept (tree_walker& tw);

private:

  static void do_init (tree_decl_elt& elt);

  // No copying!

  tree_global_command (const tree_global_command&);

  tree_global_command& operator = (const tree_global_command&);
};

// Persistent.

class
tree_persistent_command : public tree_decl_command
{
public:

  tree_persistent_command (int l = -1, int c = -1)
    : tree_decl_command ("persistent", l, c) { }

  tree_persistent_command (tree_decl_init_list *t, int l = -1, int c = -1)
    : tree_decl_command ("persistent", t, l, c) { }

  ~tree_persistent_command (void) { }

  tree_command *dup (symbol_table::scope_id scope,
                     symbol_table::context_id context) const;

  void accept (tree_walker& tw);

private:

  static void do_init (tree_decl_elt& elt);

  // No copying!

  tree_persistent_command (const tree_persistent_command&);

  tree_persistent_command& operator = (const tree_persistent_command&);
};

#endif