/************************************************************************
Copyright Notice

Copyright (c) MCNC, Clearinghouse for Networked Information Discovery and
Retrieval, 1994. 

Permission to use, copy, modify, distribute, and sell this software and
its documentation, in whole or in part, for any purpose is hereby granted
without fee, provided that

1. The above copyright notice and this permission notice appear in all
copies of the software and related documentation. Notices of copyright
and/or attribution which appear at the beginning of any file included in
this distribution must remain intact. 

2. Users of this software agree to make their best efforts (a) to return
to MCNC any improvements or extensions that they make, so that these may
be included in future releases; and (b) to inform MCNC/CNIDR of noteworthy
uses of this software. 

3. The names of MCNC and Clearinghouse for Networked Information Discovery
and Retrieval may not be used in any advertising or publicity relating to
the software without the specific, prior written permission of MCNC/CNIDR. 

THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY WARRANTY
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 

IN NO EVENT SHALL MCNC/CNIDR BE LIABLE FOR ANY SPECIAL, INCIDENTAL,
INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER
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************************************************************************/

/*@@@
File:		mdt.hxx
Version:	1.01
Description:	Class MDT - Multiple Document Table
Author:		Nassib Nassar, nrn@cnidr.org
@@@*/

#ifndef MDT_HXX
#define MDT_HXX

#include "defs.hxx"
#include "string.hxx"
#include "mdtrec.hxx"

class GPREC {
public:
	GPTYPE GpStart;
	GPTYPE GpEnd;
	GPTYPE Index;
};

class KEYREC {
public:
	CHR Key[DocumentKeySize];
	GPTYPE Index;
};

class MDT {
public:
	MDT(const STRING& DbFileStem, const GDT_BOOLEAN WrongEndian);
//	void LoadTable(const STRING& FileName);	// This is now done automatically
//	void SaveTable(const STRING& FileName);	// in the constructor and destructor.
	void AddEntry(const MDTREC& MdtRecord);
	void IndexSortByIndex();
	SIZE_T RemoveDeleted();
	void GetEntry(const SIZE_T Index, MDTREC* MdtrecPtr) const;
	void SetEntry(const SIZE_T Index, const MDTREC& MdtRecord);
//	void Expand() { };
//	void CleanUp() { };
	void Resize(const SIZE_T Entries);
	void SortKeyIndex();
	SIZE_T LookupByKey(const STRING& Key);
	SIZE_T GetMdtRecord(const STRING& Key, MDTREC* MdtrecPtr);
	SIZE_T GetMdtRecord(const GPTYPE gp, MDTREC* MdtrecPtr);
	void SortGpIndex();
	SIZE_T LookupByGp(const GPTYPE Gp);
//	INT GetMdtIndex(const GPTYPE gp);	// Use LookupByGp() instead
	GPTYPE GetNextGlobal() const;
	SIZE_T GetTotalEntries() const;
	void GetUniqueKey(STRING* StringPtr);
	void Dump() const;
	INT GetChanged() const;
	void FlipIndexBytes();
	void FlushMDTIndexes();
	~MDT();
private:
	STRING FileStem;
	FILE* MdtFp;
	KEYREC* KeyIndex;
	GPREC* GpIndex;
	SIZE_T TotalEntries;
	GDT_BOOLEAN KeyIndexSorted;
	GDT_BOOLEAN GpIndexSorted;
	GDT_BOOLEAN Changed;
	SIZE_T MaxEntries;
	GDT_BOOLEAN MdtWrongEndian;
	GDT_BOOLEAN ReadOnly;
};

typedef MDT* PMDT;

#endif