// Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

//

#include "US_STD.H"

// Class CDbStoreRecords::TIteratorC

class CDbStoreRecords::TIteratorC

	{

	friend class CDbStoreRecords;

public:

	inline TDbRecordId Current() const;

private:

	TClusterDes iDes;

	TDbRecordId iCurrent;

	};

inline TDbRecordId CDbStoreRecords::TIteratorC::Current() const

	{return iCurrent;}

// Class CDbStoreRecords::CIter

NONSHARABLE_CLASS(CDbStoreRecords::CIter) : public CDbRecordIter

	{

public:

	CIter(CDbStoreRecords& aRecords);

private:

	inline CDbStoreRecords& Records() const;

//

	TInt Count() const;

	TDbRecordId CurrentL();

	TBool GotoL(TDbPosition aPosition);

	TBool GotoL(TDbRecordId aRecordId,RDbTableRow& aBuffer);

	TBool SeekL(const TDbLookupKey& aKey,RDbTable::TComparison aComparison);

	TDeleted DoDeletedL(TDbPosition aPosition,TDbRecordId aRecordId,const RDbTableRow* aRow);

private:

	CDbStoreRecords::TIteratorC iIter;

	};

CDbStoreRecords::CIter::CIter(CDbStoreRecords& aRecords)

	: CDbRecordIter(aRecords)

	{}

inline CDbStoreRecords& CDbStoreRecords::CIter::Records() const

	{return STATIC_CAST(CDbStoreRecords&,Host());}

TInt CDbStoreRecords::CIter::Count() const

	{

	return Records().Count();

	}

TDbRecordId CDbStoreRecords::CIter::CurrentL()

	{

	return iIter.Current();

	}

TBool CDbStoreRecords::CIter::GotoL(TDbPosition aPosition)

	{

	return Records().GotoL(aPosition,iIter);

	}

TBool CDbStoreRecords::CIter::GotoL(TDbRecordId aRecordId,RDbTableRow&)

	{

	return Records().GotoL(aRecordId,iIter);

	}

TBool CDbStoreRecords::CIter::SeekL(const TDbLookupKey&,RDbTable::TComparison)

//

// Cannot do this on a table iterator

//

	{

	Panic(EDbCannotSeek);

	return EFalse;

	}

CDbStoreRecords::CIter::TDeleted CDbStoreRecords::CIter::DoDeletedL(TDbPosition aPosition,TDbRecordId,const RDbTableRow*)

//

// reposition to next after a record is deleted

// Previous only required for reversed (index) iterators

//

	{

	return Records().DeletedL(aPosition,iIter) ? EAtRow : ENoRow;

	}

// Class CDbStoreRecords::TToken

void CDbStoreRecords::TToken::ExternalizeL(RWriteStream& aStream) const

	{

	aStream<<iHead<<iNext.Value()<<TCardinality(iCount)<<TUint32(iAutoIncrement);

	}

void CDbStoreRecords::TToken::InternalizeL(RReadStream& aStream)

	{

	aStream>>iHead;

	iNext=aStream.ReadUint32L();

	TCardinality card;

	aStream>>card;

	iCount=card;

	iAutoIncrement=aStream.ReadUint32L();

	}

// Class CDbStoreRecords

CDbStoreRecords::CDbStoreRecords(CClusterCache& aCache)

	: iCache(aCache)

	{}

CDbStoreRecords::~CDbStoreRecords()

	{

	iMap.Close();

	}

TStreamId CDbStoreRecords::CreateL(CClusterCache& aCache)

//

// Create a new record space in the store, do not create a records object

//

	{

	TToken token;

	token.iHead=ClusterId(aCache.Store().ExtendL());

	aCache.ClusterL().Create(token.iHead);

	token.iNext=RecordId(token.iHead,0);

	token.iCount=0;

	token.iAutoIncrement=0;

	RStoreWriteStream strm;

	TStreamId id=strm.CreateLC(aCache.Store());

	strm<<token;

	strm.CommitL();

	CleanupStack::PopAndDestroy();

	return id;

	}

CDbStoreRecords* CDbStoreRecords::NewL(CClusterCache& aCache,const CDbStoreDef& aDef)

//

// Create a record space

//

	{

	CDbStoreRecords* self=new(ELeave) CDbStoreRecords(aCache);

	CleanupStack::PushL(self);

	self->iClustering=aDef.Clustering();

	self->iTokenId=aDef.TokenId();

	CleanupStack::Pop();

	return self;

	}

TBool CDbStoreRecords::RestoreL()

//

// Restore an existing record space from the store

//

	{

	RStoreReadStream strm;

	strm.OpenLC(iCache.Store(),iTokenId);

	strm>>iToken;

	CleanupStack::PopAndDestroy();

	iLinks.Invalidate();

	iMap.ResetL(iToken.iHead);

	return EFalse;

	}

void CDbStoreRecords::DestroyL()

//

// Destroy the record space

//

	{

	iCache.Store().DeleteL(iTokenId);

	}

TInt CDbStoreRecords::CardinalityL(CStreamStore& aStore,const CDbStoreDef& aDef)

//

// Return the record count without constructing the entire table

//

	{

	RStoreReadStream strm;

	strm.OpenLC(aStore,aDef.TokenId());

	TToken token;

	strm>>token;

	CleanupStack::PopAndDestroy();

	return token.iCount;

	}

void CDbStoreRecords::SynchL()

//

// write persistent token to the store

//

	{

	RStoreWriteStream strm;

	strm.ReplaceLC(iCache.Store(),iTokenId);

	strm<<iToken;

	strm.CommitL();

	CleanupStack::PopAndDestroy();

	}

TInt CDbStoreRecords::DiscardL(TClusterId& aCluster)

//

// discard the cluster as part of the incremental drop

// aCluster is updated to the next cluster, the number of records contained is returned

//

	{

	TClusterDes des;

	DesL(des,aCluster);

	CCluster* cluster=iCache.Cluster(aCluster);

	if (cluster)

		cluster->Discard();

	iCache.Store().DeleteL(aCluster);

	aCluster=des.iNext;

	TInt records=0;

	for (TUint members=des.iMembership;members;members&=members-1)

		++records;

	return records;

	}

TClusterId CDbStoreRecords::AlterL(TClusterId aCluster,CCluster::MAlter& aAlterer)

	{

	CCluster& cluster=iCache.ClusterL(aCluster);

	cluster.AlterL(aAlterer);

	return cluster.Des().iNext;

	}

TPtrC8 CDbStoreRecords::ReadL(TDbRecordId aRecordId) const

	{

	return iCache.ClusterL(ClusterId(aRecordId)).RecordL(RecordIndex(aRecordId));

	}

TUint CDbStoreRecords::AutoIncrementL()

//

// Provide the next value for an auto-increment column

//

	{

	return iToken.iAutoIncrement++;

	}

TUint8* CDbStoreRecords::UpdateRecordL(TDbRecordId aRecordId,TInt aNewSize)

//

// read the cluster and return a writable descriptor over the new record data

//

	{

	return iCache.ClusterL(ClusterId(aRecordId)).UpdateL(RecordIndex(aRecordId),aNewSize);

	}

TUint8* CDbStoreRecords::DoNewL(TInt aRecordSize)

//

// Phase 1 of appending a records

//

	{

	return UpdateRecordL(iToken.iNext,aRecordSize);

	}

TDbRecordId CDbStoreRecords::AppendL()

//

// Phase 2 of appending a record

//

	{

	TDbRecordId id=iToken.iNext;

	TClusterId clusterId=ClusterId(id);

	CCluster* cluster=iCache.Cluster(clusterId);

	__ASSERT(cluster);

	TInt nextIndex=RecordIndex(id)+1;

	if (nextIndex>=iClustering || cluster->IsFull())

		{

		TClusterId newcluster=ClusterId(iCache.Store().ExtendL());

		cluster->Relink(newcluster);

		cluster->FlushL();

		cluster->Create(newcluster);

		iMap.BindL(clusterId,newcluster);

		iLinks.Bind(clusterId,newcluster,iMap);

		iToken.iNext=RecordId(newcluster,0);

		}

	else

		iToken.iNext=RecordId(clusterId,nextIndex);

	++iToken.iCount;

	return id;

	}

TUint8* CDbStoreRecords::DoReplaceL(TDbRecordId aRecordId,TInt aRecordSize)

	{

	return UpdateRecordL(aRecordId,aRecordSize);

	}

void CDbStoreRecords::DoEraseL(TDbRecordId aRecordId)

	{

	TClusterId clusterId=ClusterId(aRecordId);

	CCluster& cluster=iCache.ClusterL(clusterId);

	if (!cluster.DeleteL(RecordIndex(aRecordId)) && clusterId!=ClusterId(iToken.iNext))

		{	// cluster is now empty, but don't drop the last cluster, coz it hasn't all been used!

		TClusterDes des;

		TClusterId prev=PreviousClusterL(des,clusterId);

		TClusterId next=cluster.Des().iNext;	// next cluster

		cluster.Discard();						// discard the cluster

		iCache.Store().DeleteL(clusterId);

		if (prev!=KNullClusterId)

			iCache.ClusterL(prev).Relink(next);

		else

			iToken.iHead=next;

		iLinks.Drop(clusterId,next);

		iMap.DropL(clusterId,next);

		}

	--iToken.iCount;

	}

CDbRecordIter* CDbStoreRecords::IteratorL()

	{

	return new(ELeave) CIter(*this);

	}

void CDbStoreRecords::CompleteMapL()

	{

	TClusterId cluster=iMap.LastBound();

	TClusterDes des;

	DesL(des,cluster);

	do cluster=NextClusterL(des,cluster); while (cluster!=KNullClusterId);

	}

void CDbStoreRecords::DesL(TClusterDes& aDes,TClusterId aCluster)

//

// Read just the cluster descriptor

//

	{

	CCluster* cluster=iCache.Cluster(aCluster);

	if (cluster)

		aDes=cluster->Des();

	else

		{

		RStoreReadStream stream;

		stream.OpenLC(iCache.Store(),aCluster);

		stream>>aDes;

		CleanupStack::PopAndDestroy();

		}

	}

TClusterId CDbStoreRecords::NextClusterL(TClusterDes& aDes,TClusterId aCluster)

	{

	TClusterId next=aDes.iNext;

	if (next==KNullClusterId)

		iMap.Complete(aCluster);

	else

		{

		iMap.BindL(aCluster,next);

		iLinks.Bind(aCluster,next,iMap);

		DesL(aDes,next);

		}

	return next;

	}

TBool CDbStoreRecords::LocateL(TClusterId aCluster)

//

// Locate the cluster in the table. If not present return EFalse

// If present fill up the cluster link cache with the loop

// containing the predecessor to aCluster

// aDes will have the previous cluster des

//

	{

	TClusterId cluster=aCluster;

	__ASSERT(aCluster!=iToken.iHead);

	__ASSERT(!iLinks.At(aCluster,cluster));

//

	if (!iMap.IsComplete())

		CompleteMapL();

//

	TClusterDes des;

	TClusterId links[RClusterMap::ESeparation];

	TClusterId* p=links;

	for (TInt n=RClusterMap::ESeparation;n>0;--n)

		{

		*p++=cluster;

		TBool r=iMap.At(cluster,cluster);

		DesL(des,cluster);

		if (r)

			{

			__ASSERT(cluster!=KNullClusterId);	// only iHead->Null

			iLinks.Reset(cluster);

			while (aCluster!=des.iNext)

				cluster=NextClusterL(des,cluster);

			iLinks.Add(links,p);

			return ETrue;

			}

		cluster=des.iNext;

		}

	return EFalse;	// not in this table!

	}

TClusterId CDbStoreRecords::PreviousClusterL(TClusterDes& aDes,TClusterId aCluster)

	{

	if (aCluster==iToken.iHead)

		return KNullClusterId;

	if (!iLinks.At(aCluster,aCluster))

		{

		__DEBUG(TBool dbgchk=) LocateL(aCluster);

		__ASSERT(dbgchk);

		__DEBUG(dbgchk=) iLinks.At(aCluster,aCluster);

		__ASSERT(dbgchk);

		}

	DesL(aDes,aCluster);

	return aCluster;

	}

TBool CDbStoreRecords::GotoL(TDbPosition aPosition,TIteratorC& anIterator)

	{

	TClusterId cluster=ClusterId(anIterator.iCurrent);

	TInt index=RecordIndex(anIterator.iCurrent);

	switch (aPosition)

		{

	default:

		__ASSERT(0);

	case EDbFirst:

		DesL(anIterator.iDes,cluster=iToken.iHead);

		iLinks.Reset(cluster);

		index=-1;

		// drop through to next

	case EDbNext:

		for (;;)

			{

			TUint membership=anIterator.iDes.iMembership;

			while (++index<KMaxClustering)

				{

				if ((membership>>index)&1)

					{

					__ASSERT(cluster!=ClusterId(iToken.iNext)||index<RecordIndex(iToken.iNext));

					anIterator.iCurrent=RecordId(cluster,index);

					return ETrue;

					}

				}

			cluster=NextClusterL(anIterator.iDes,cluster);

			if (cluster==KNullClusterId)

				return EFalse;	// ran out of data

			index=-1;

			}

	case EDbLast:

		DesL(anIterator.iDes,cluster=ClusterId(iToken.iNext));

		index=KMaxClustering;

		// drop through to previous

	case EDbPrevious:

		for (;;)

			{

			TUint membership=anIterator.iDes.iMembership;

			while (--index>=0)

				{

				if ((membership>>index)&1)

					{

					anIterator.iCurrent=RecordId(cluster,index);

					return ETrue;

					}

				}

			__ASSERT(index==-1);

			cluster=PreviousClusterL(anIterator.iDes,cluster);

			if (cluster==KNullClusterId)

				return EFalse;	// ran out of data

			index=KMaxClustering;

			}

		}

	}

TBool CDbStoreRecords::DeletedL(TDbPosition aPosition,TIteratorC& anIterator)

//

// Record has been deleted

//

	{

	anIterator.iDes.iMembership&=~(1<<RecordIndex(anIterator.iCurrent));

	return GotoL(aPosition,anIterator);

	}

TBool CDbStoreRecords::GotoL(TDbRecordId aRecordId,TIteratorC& anIterator)

//

// Set the iterator to the record id, return false if the record is not present

//

	{

	TClusterId cluster=ClusterId(aRecordId);

	if (cluster!=iToken.iHead && !iLinks.Has(cluster) && !LocateL(cluster))

		return EFalse;

	anIterator.iCurrent=aRecordId;

	DesL(anIterator.iDes,cluster);

	return (anIterator.iDes.iMembership>>RecordIndex(aRecordId))&1;

	}

TBool CDbStoreRecords::ExistsL(TDbRecordId aRecordId)

//

// Ensure that the record is in this table

//

	{

	TIteratorC iter;

	return GotoL(aRecordId,iter);

	}

// Class HUnicodeCompressor

NONSHARABLE_CLASS(HUnicodeCompressor) : public TStreamFilter

	{

public:

	HUnicodeCompressor(MStreamBuf* aSink);

private:

	void DoRelease();

	void DoSynchL();

	TInt Capacity(TInt aMaxLength);

	TInt FilterL(TAny* aPtr,TInt aMaxLength,const TUint8*& aFrom,const TUint8* anEnd);

private:

	enum {EFlushBufferSize=16};

private:

	TUnicodeCompressor iCompressor;

	};

HUnicodeCompressor::HUnicodeCompressor(MStreamBuf* aSink)

	{

	Set(aSink,EAttached|EWrite);

	}

void HUnicodeCompressor::DoRelease()

	{

	TStreamFilter::DoRelease();

	delete this;

	}

TInt HUnicodeCompressor::Capacity(TInt aMaxLength)

//

// Return the maximum guaranteed input used for aMaxLength output.