/*

Copyright (C) 1996-2017 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_pt_h)
#define octave_pt_h 1

#include "octave-config.h"

#include <string>

#include <iosfwd>

class octave_function;

namespace octave
{
  class tree_walker;

  // Base class for the parse tree.

  class tree
  {
  public:

    tree (int l = -1, int c = -1)
      : line_num (l), column_num (c), bp (nullptr) { }

    // No copying!

    tree (const tree&) = delete;

    tree& operator = (const tree&) = delete;

    virtual ~tree (void) = default;

    virtual int line (void) const { return line_num; }

    virtual int column (void) const { return column_num; }

    void line (int l) { line_num = l; }

    void column (int c) { column_num = c; }

    void set_location (int l, int c)
    {
      line_num = l;
      column_num = c;
    }

    virtual void set_breakpoint (const std::string& condition)
    {
      if (bp)
        *bp = condition;
      else
        bp = new std::string(condition);
    }

    virtual void delete_breakpoint (void) { if (bp) delete bp; bp = nullptr; }

    bool meets_bp_condition (void) const;

    bool is_breakpoint (bool check_active = false) const
    { return bp && (! check_active || meets_bp_condition ()); }

    // breakpoint condition, or "0" (i.e., "false") if no breakpoint.
    // To distinguish "0" from a disabled breakpoint, test "is_breakpoint" too.
    const std::string bp_cond (void) const
    { return bp ? *bp : "0"; }

    std::string str_print_code (void);

    virtual void accept (tree_walker& tw) = 0;

  private:

    // The input line and column where we found the text that was
    // eventually converted to this tree node.
    int line_num;
    int column_num;

    // Breakpoint flag: NULL if no breakpoint, or the condition if there is one
    std::string *bp;
  };
}

#if defined (OCTAVE_USE_DEPRECATED_FUNCTIONS)

OCTAVE_DEPRECATED (4.4, "use 'octave::tree' instead")
typedef octave::tree tree;

#endif

#endif