// Copyright (c) 1997-2009 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 "agsiterator.h"

#include "agsindex.h"

#include "agsstreamidset.h"

#include "agsentrymanager.h"

#include "agmdate.h"

#include "agmentry.h"

#include "agmpanic.h"

// --------------------------TAgnIterator-------------------

TAgnIterator::TAgnIterator(CAgnIndex* aIndex, const TAgnFilter& aFilter):

         TAgnIteratorBase()

/**

@internalAll

*/

	{

	iArray = aIndex;

	iFilter = aFilter;

	}

TAgnIterator::TAgnIterator()

	{

	}

const CAgnIndex* TAgnIterator::Array() const

//

// return array that is being iterated over

//

	{

	return (iArray);

	}

 void TAgnIterator::SetCursor(TInt aCursor)

//

// set the current position of iterator

//

	{

	iCursor = aCursor;

	}

 TInt TAgnIterator::Cursor() const

//

// return current position of iterator

//

	{

	return (iCursor);

	}

void TAgnIterator::SetCurrentKey(const TTime& aKeyValue)

//

// set the current key value

//

	{

	iCurrentKey = aKeyValue;

	}

const CAgnSimpleEntry& TAgnIterator::CurrentElement() const

/**

return current element 

@internalAll

*/

	{

	return *(iArray->Get(iCursor));

	}

const TTime& TAgnIterator::CurrentKey() const

/**

return current key value

internalComponent

*/

	{

	return (iCurrentKey);

	}

 TBool TAgnIterator::IsValidElement()

//

// Is current element valid w.r.t. filter?

//

	{

	__ASSERT_ALWAYS(iCursor>=0 && iCursor<iArray->Count(),Panic(EAgmErrOutsideArrayRange));

	return(iFilter.IsValid(CurrentElement()));

	}

 void TAgnIterator::NextL()

/**

position to next element which is valid w.r.t. filter?

@internalAll

*/

	{

	iPreviousKey = iCurrentKey;

	if (iArray->Count() > 0)

		{

		TBool found = EFalse;

		iArray->NextL(iCurrentKey, iCursor);

		TTime target = iPreviousKey;

		MovedForwardL(target);

		while(!found && !AtEnd()) 

			{

			found = IsValidElement();

			if (!found)

				{

				iPreviousKey = iCurrentKey;

				iArray->NextL(iCurrentKey, iCursor);

				TTime target = iPreviousKey;

				MovedForwardL(target);

				}

			}

		}

	}

void TAgnIterator::PreviousL()

/**

position to previous element which is valid w.r.t. filter?

@internalAll

*/

	{

	iPreviousKey = iCurrentKey;

	if (iArray->Count() > 0)

		{

		TBool found = EFalse;

		iArray->PreviousL(iCurrentKey, iCursor);

		TTime target = iPreviousKey;

		MovedBackL(target);

		while(!found && !AtStart()) 

			{

			found = IsValidElement();

			if (!found)

				{

				iArray->PreviousL(iCurrentKey, iCursor);

				MovedBackL(target);

				}

			}

		}

	}

 void TAgnIterator::StartL() 

/**

Position to first valid element

@internalAll

*/

	{ 

	SetCursor(0);	

	if (iArray->Count() > 0)

		{

		iArray->GetKeyValueL(0,iCurrentKey);

		while(!AtEnd() && !IsValidElement())// iterate until entry matches filter

			{

			NextL();

			}

		}

	}

TBool TAgnIterator::FirstL(TTime& aTargetKey)

//

//

//

	{

	TInt pos = 0;

	iCurrentKey = aTargetKey;

	TBool found = iArray->FirstL(iCurrentKey,pos);

	SetCursor(pos);		

	found = MovedToL(aTargetKey);

	aTargetKey = iCurrentKey;

	return found;

	}

 TBool TAgnIterator::GotoL(TTime& aTargetKey) 

/**

Position to the first element whose keyvalue is >= aTargetValue

@internalComponent

*/

	{

	TBool found = EFalse;

	if (iArray->Count() > 0)

		{

		found = FirstL(aTargetKey);

		if (found) 

			{

			while(!AtEnd())

				{

				found = IsValidElement();

				if (found)

					break; // iterate until entry matches filter

				NextL();

				}

			aTargetKey = iCurrentKey;

			}

		}

	return (found);

	}

TBool TAgnIterator::FirstLessOrEqualL(TTime& aTargetKey)

	{

	TInt pos = 0;

	iCurrentKey = aTargetKey;

	TBool found = iArray->FirstLessOrEqualL(iCurrentKey,pos);

	SetCursor(pos);		

	found = MovedBackL(aTargetKey);

	aTargetKey = iCurrentKey;

	return found;

	}

TBool TAgnIterator::GotoLessOrEqualL(TTime& aKeyValue)

/**

Position iterator at first element whose key value is less than or equal to aKeyValue

@internalAll

*/

	{

	TBool found = EFalse;

	if (iArray->Count() > 0)

		{

		found = FirstLessOrEqualL(aKeyValue);

		while(iCursor >= 0)

			{

			found = IsValidElement();

			if (found) 

				break; // iterate until entry matches filter

			PreviousL();

			}

		aKeyValue = iCurrentKey;

		return (found);

		}

	return (EFalse);

	}

TBool TAgnIterator::AtEnd()

/**

Is the current position beyond the end of the array

@internalAll

*/

	{

	return (iArray->Count() == 0 || iCursor >= iArray->Count());

	}

TBool TAgnIterator::AtStart()

/**

Is the current position before the start of the array

@internalAll

*/

	{

	return (iArray->Count() == 0 || iCursor < 0);

	}

// TAgnEntryIter //

TAgnEntryIter::TAgnEntryIter(CAgnStreamIdSet& aStreamIdSet, CAgnEntryManager& aEntryManager)

	: iStreamIdSet(aStreamIdSet), iEntryManager(aEntryManager)

/** Constructs the entry iterator.

@param aModel The agenda model over which the iterator will iterate. */

	{

	}

TBool TAgnEntryIter::SetToFirstL()

/** Resets the iterator to the first entry in the file.

@internalAll

@return ETrue if there is at least one entry and its ID can be extracted (using 

At()). Otherwise EFalse. */

	{

	iStreamIdSet.ResetIteratorToStart();

	if (iStreamIdSet.Count() == 0)

		{

		return (EFalse);

		}

	TInt currentStream=0;	

	// If the contents of a stream are corrupt (indicated by iEntryManager.EntryCount()

	// being 0 - assuming its not an empty file - then skip to the next stream and try that one

		FOREVER

			{

			++currentStream;

			TStreamId id;

			if (!iStreamIdSet.At(id))

				return (EFalse);

			//tell the Entry Manager to use the iterator buffer

			iEntryManager.iUseIteratorBuffer = ETrue;

			iEntryCount = iEntryManager.RestoreBufferL(id);

			//reset the flag in case other buffers need to be used

			iEntryManager.iUseIteratorBuffer = EFalse;

			if (iEntryCount == 0)

				{

				if (!iStreamIdSet.Next())

					return (EFalse);

				continue;

				}

			else

				break;

			} 

	__ASSERT_DEBUG(currentStream==1,Panic(EAgmErrCorruptFile));

	iEntryIter=0;

	return (ETrue);

	}

TBool TAgnEntryIter::NextL()

/** Moves the iterator to the next entry.

@internalAll

@return ETrue if there is at least one more entry. EFalse if not. */

	{

	// If we're at the last entry in this cluster, advance to the next cluster

	if (iEntryIter + 1 == iEntryCount)

		{

		FOREVER

			{

			if (!iStreamIdSet.Next())

				return (EFalse);

			TStreamId id;

			if (!iStreamIdSet.At(id))

				return (EFalse);

			//tell the Entry Manager to use the iterator buffer

			iEntryManager.iUseIteratorBuffer = ETrue;

			iEntryCount = iEntryManager.RestoreBufferL(id);

			//reset the flag in case other buffers need to be used

			iEntryManager.iUseIteratorBuffer = EFalse;

			if (iEntryCount == 0)

				continue;

			else

				break;

			} 

		iEntryIter=0;

		}

	else

		++iEntryIter;

	return (ETrue);

	}

TAgnEntryId TAgnEntryIter::At()

/** Gets the ID of the entry at the current iterator position.

@internalAll

@return The ID of the entry at the current iterator position. */

	{

//	__ASSERT_DEBUG(iEntryIter < iEntryManager.EntryCount() && iEntryIter >= 0,

//				Panic(_L("Invalid index into entry cluster")));

	//tell the Entry Manager to use the iterator buffer

	iEntryManager.iUseIteratorBuffer = ETrue;

	TAgnEntryId entryId = iEntryManager[iEntryIter]->EntryId();

	//reset the flag in case other buffers need to be used

	iEntryManager.iUseIteratorBuffer = EFalse;

	return entryId;

	}