////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 1996-2021 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// 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
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if ! defined (octave_pt_idx_h)
#define octave_pt_idx_h 1

#include "octave-config.h"

#include <list>

class octave_map;
class octave_value;
class octave_value_list;

#include "str-vec.h"

#include "pt-exp.h"
#include "pt-walk.h"

namespace octave
{
  class octave_lvalue;
  class symbol_scope;
  class tree_argument_list;
  class tree_evaluator;

  // Index expressions.

  class tree_index_expression : public tree_expression
  {
  public:

    tree_index_expression (tree_expression *e = nullptr,
                           tree_argument_list *lst = nullptr,
                           int l = -1, int c = -1, char t = '(');

    tree_index_expression (tree_expression *e, const std::string& n,
                           int l = -1, int c = -1);

    tree_index_expression (tree_expression *e, tree_expression *df,
                           int l = -1, int c = -1);

    // No copying!

    tree_index_expression (const tree_index_expression&) = delete;

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

    ~tree_index_expression (void);

    tree_index_expression *
    append (tree_argument_list *lst = nullptr, char t = '(');

    tree_index_expression * append (const std::string& n);

    tree_index_expression * append (tree_expression *df);

    bool is_index_expression (void) const { return true; }

    std::string name (void) const;

    tree_expression * expression (void) { return m_expr; }

    std::list<tree_argument_list *> arg_lists (void) { return m_args; }

    std::string type_tags (void) { return m_type; }

    std::list<string_vector> arg_names (void) { return m_arg_nm; }

    std::list<tree_expression *> dyn_fields (void) { return m_dyn_field; }

    void mark_word_list_cmd (void) { m_word_list_cmd = true; }

    bool is_word_list_cmd (void) const { return m_word_list_cmd; }

    bool lvalue_ok (void) const { return m_expr->lvalue_ok (); }

    bool rvalue_ok (void) const { return true; }

    octave_lvalue lvalue (tree_evaluator& tw);

    tree_index_expression * dup (symbol_scope& scope) const;

    octave_value evaluate (tree_evaluator& tw, int nargout = 1)
    {
      octave_value_list retval = evaluate_n (tw, nargout);

      return retval.length () > 0 ? retval(0) : octave_value ();
    }

    octave_value_list evaluate_n (tree_evaluator& tw, int nargout = 1);

    void accept (tree_walker& tw)
    {
      tw.visit_index_expression (*this);
    }

    std::string
    get_struct_index
    (tree_evaluator& tw, std::list<string_vector>::const_iterator p_arg_nm,
     std::list<tree_expression *>::const_iterator p_dyn_field) const;

  private:

    // The LHS of this index expression.
    tree_expression *m_expr;

    // The indices (only valid if type == paren || type == brace).
    std::list<tree_argument_list *> m_args;

    // The type of this index expression.
    std::string m_type;

    // The names of the arguments.  Used for constant struct element
    // references.
    std::list<string_vector> m_arg_nm;

    // The list of dynamic field names, if any.
    std::list<tree_expression *> m_dyn_field;

    // TRUE if this expression was parsed as a word list command.
    bool m_word_list_cmd;

    tree_index_expression (int l, int c);

    octave_map make_arg_struct (void) const;
  };
}

#endif