/*
  Copyright(C) 2011-2016 Brazil

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

#pragma once

#include "cursor.hpp"

namespace grn {
namespace dat {

class Trie;

class GRN_DAT_API IdCursor : public Cursor {
 public:
  IdCursor();
  ~IdCursor();

  void open(const Trie &trie,
            const String &min_str,
            const String &max_str,
            UInt32 offset = 0,
            UInt32 limit = MAX_UINT32,
            UInt32 flags = 0);

  void open(const Trie &trie,
            UInt32 min_id,
            UInt32 max_id,
            UInt32 offset = 0,
            UInt32 limit = MAX_UINT32,
            UInt32 flags = 0);

  void close() override;

  const Key &next() override;

  UInt32 offset() const override {
    return offset_;
  }
  UInt32 limit() const override {
    return limit_;
  }
  UInt32 flags() const override {
    return flags_;
  }

 private:
  const Trie *trie_;
  UInt32 offset_;
  UInt32 limit_;
  UInt32 flags_;

  UInt32 cur_;
  UInt32 end_;
  UInt32 count_;

  IdCursor(const Trie &trie, UInt32 offset, UInt32 limit, UInt32 flags);

  UInt32 fix_flags(UInt32 flags) const;
  void init(UInt32 min_id, UInt32 max_id);
  void swap(IdCursor *cursor);

  // Disallows copy and assignment.
  IdCursor(const IdCursor &);
  IdCursor &operator=(const IdCursor &);
};

}  // namespace dat
}  // namespace grn
