#ifndef __FILEHEAP_HPP
#define __FILEHEAP_HPP

class FileHeapStorage {
public:
        FileHeapStorage() {}
        virtual ~FileHeapStorage() {}
        
        virtual int Read(void *buf, int buflen) =0;
        virtual int Write(const void *buf, int buflen) =0;
        virtual long Tell() =0;
        virtual int Seek(long pos, int from) =0;
};

class FileHeap {
protected:
        FileHeapStorage *storage;
public:
        FileHeap(FileHeapStorage *s) : storage(s) {}
        virtual ~FileHeap() {}
        
        typedef unsigned long recid;
        static const recid NoRecord;
        
        virtual recid Alloc(int rsize) =0;
        virtual int Free(recid r) =0;
        virtual int Read(recid r, void *data, int datalen) =0;
        virtual int Write(recid r, const void *data, int datalen) =0;
        virtual void Flush() =0;
        
        virtual int FindFirst(recid r[], int maxrecids, int *recids) =0;
        virtual int FindNext(recid from, recid r[], int maxrecids, int *recids) =0;

        virtual int cardinality() =0;
        virtual unsigned long count_approx() =0;
        virtual unsigned long count_exact() =0;
};

#endif