/*

Copyright (C) 1996, 1997 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 2, 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, write to the Free
Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.

*/

#if !defined (octave_tree_select_h)
#define octave_tree_select_h 1

class expression;
class tree_statement_list;

class tree_walker;

#include "base-list.h"
#include "comment-list.h"
#include "pt-cmd.h"

// If.

class
tree_if_clause
{
public:

  tree_if_clause (void)
    : expr (0), list (0), lead_comm (0) { }

  tree_if_clause (tree_statement_list *l, octave_comment_list *lc = 0)
    : expr (0), list (l), lead_comm (lc) { }

  tree_if_clause (tree_expression *e, tree_statement_list *l,
		  octave_comment_list *lc = 0)
    : expr (e), list (l), lead_comm (lc) { }

  ~tree_if_clause (void);

  bool is_else_clause (void)
    { return ! expr; }

  int eval (void);

  tree_expression *condition (void) { return expr; }

  tree_statement_list *commands (void) { return list; }

  octave_comment_list *leading_comment (void) { return lead_comm; }

  void accept (tree_walker& tw);

private:

  // The condition to test.
  tree_expression *expr;

  // The list of statements to evaluate if expr is true.
  tree_statement_list *list;

  // Comment preceding ELSE or ELSEIF token.
  octave_comment_list *lead_comm;

  // No copying!

  tree_if_clause (const tree_if_clause&);

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

class
tree_if_command_list : public octave_base_list<tree_if_clause *>
{
public:

  tree_if_command_list (void) { }

  tree_if_command_list (tree_if_clause *t) { append (t); }

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

  void eval (void);

  void accept (tree_walker& tw);

private:

  // No copying!

  tree_if_command_list (const tree_if_command_list&);

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

class
tree_if_command : public tree_command
{
public:

  tree_if_command (int l = -1, int c = -1)
    : tree_command (l, c), list (0), lead_comm (0), trail_comm (0) { }

  tree_if_command (tree_if_command_list *lst, octave_comment_list *lc,
		   octave_comment_list *tc, int l = -1, int c = -1)
    : tree_command (l, c), list (lst), lead_comm (lc), trail_comm (tc) { }

  ~tree_if_command (void);

  void eval (void);

  tree_if_command_list *cmd_list (void) { return list; }

  octave_comment_list *leading_comment (void) { return lead_comm; }

  octave_comment_list *trailing_comment (void) { return trail_comm; }

  void accept (tree_walker& tw);

private:

  // List of if commands (if, elseif, elseif, ... else, endif)
  tree_if_command_list *list;

  // Comment preceding IF token.
  octave_comment_list *lead_comm;

  // Comment preceding ENDIF token.
  octave_comment_list *trail_comm;

  // No copying!

  tree_if_command (const tree_if_command&);

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

// Switch.

class
tree_switch_case
{
public:

  tree_switch_case (void)
    : label (0), list (0), lead_comm (0) { }

  tree_switch_case (tree_statement_list *l, octave_comment_list *lc = 0)
    : label (0), list (l), lead_comm (lc) { }

  tree_switch_case (tree_expression *e, tree_statement_list *l,
		    octave_comment_list *lc = 0)
    : label (e), list (l), lead_comm (lc) { }

  ~tree_switch_case (void);

  bool is_default_case (void) { return ! label; }

  bool label_matches (const octave_value& val);

  int eval (const octave_value& val);

  void eval_error (void);

  tree_expression *case_label (void) { return label; }

  tree_statement_list *commands (void) { return list; }

  octave_comment_list *leading_comment (void) { return lead_comm; }

  void accept (tree_walker& tw);

private:

  // The case label.
  tree_expression *label;

  // The list of statements to evaluate if the label matches.
  tree_statement_list *list;

  // Comment preceding CASE or OTHERWISE token.
  octave_comment_list *lead_comm;

  // No copying!

  tree_switch_case (const tree_switch_case&);

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

class
tree_switch_case_list : public octave_base_list<tree_switch_case *>
{
public:

  tree_switch_case_list (void) { }

  tree_switch_case_list (tree_switch_case *t) { append (t); }

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

  void eval (const octave_value& val);

  void accept (tree_walker& tw);

private:

  // No copying!

  tree_switch_case_list (const tree_switch_case_list&);

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

class
tree_switch_command : public tree_command
{
public:

  tree_switch_command (int l = -1, int c = -1)
    : tree_command (l, c), expr (0), list (0), lead_comm (0),
      trail_comm (0) { }

  tree_switch_command (tree_expression *e, tree_switch_case_list *lst,
		       octave_comment_list *lc, octave_comment_list *tc, 
		       int l = -1, int c = -1)
    : tree_command (l, c), expr (e), list (lst), lead_comm (lc),
      trail_comm (tc) { }

  ~tree_switch_command (void);

  void eval (void);

  void eval_error (void);

  tree_expression *switch_value (void) { return expr; }

  tree_switch_case_list *case_list (void) { return list; }

  octave_comment_list *leading_comment (void) { return lead_comm; }

  octave_comment_list *trailing_comment (void) { return trail_comm; }

  void accept (tree_walker& tw);

private:

  // Value on which to switch.
  tree_expression *expr;

  // List of cases (case 1, case 2, ..., default)
  tree_switch_case_list *list;

  // Comment preceding SWITCH token.
  octave_comment_list *lead_comm;

  // Comment preceding ENDSWITCH token.
  octave_comment_list *trail_comm;

  // No copying!

  tree_switch_command (const tree_switch_command&);

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

#endif

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