/*
 * Copyright 2007, Ingo Weinhold, ingo_weinhold@gmx.de.
 * All rights reserved. Distributed under the terms of the MIT license.
 */
#ifndef INDEX_H
#define INDEX_H

#include <SupportDefs.h>

#include "String.h"

class AbstractIndexEntryIterator;
class Entry;
class IndexEntryIterator;
class Node;
class Volume;

// Index
class Index {
public:
        Index(Volume *volume, const char *name, uint32 type,
                  bool fixedKeyLength, size_t keyLength = 0);
        virtual ~Index();

        status_t InitCheck() const;

        Volume *GetVolume() const               { return fVolume; }
        void GetVolume(Volume *volume)  { fVolume = volume; }

        const char *GetName() const             { return fName.GetString(); }
        uint32 GetType() const                  { return fType; }
        bool HasFixedKeyLength() const  { return fFixedKeyLength; }
        size_t GetKeyLength() const             { return fKeyLength; }

        virtual int32 CountEntries() const = 0;

        bool GetIterator(IndexEntryIterator *iterator);
        bool Find(const uint8 *key, size_t length,
                          IndexEntryIterator *iterator);

        // debugging
        void Dump();

protected:
        virtual AbstractIndexEntryIterator *InternalGetIterator() = 0;
        virtual AbstractIndexEntryIterator *InternalFind(const uint8 *key,
                                                                                                         size_t length) = 0;

protected:
        Volume          *fVolume;
        status_t        fInitStatus;
        String          fName;
        uint32          fType;
        size_t          fKeyLength;
        bool            fFixedKeyLength;
};

// IndexEntryIterator
class IndexEntryIterator {
public:
        IndexEntryIterator();
        IndexEntryIterator(Index *index);
        ~IndexEntryIterator();

        Entry *GetCurrent();
        Entry *GetCurrent(uint8 *buffer, size_t *keyLength);
        Entry *GetPrevious();
        Entry *GetNext();
        Entry *GetNext(uint8 *buffer, size_t *keyLength);

        status_t Suspend();
        status_t Resume();

private:
        void SetIterator(AbstractIndexEntryIterator *iterator);

private:
        friend class Index;

        AbstractIndexEntryIterator      *fIterator;
};

#endif  // INDEX_H