// Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
// which accompanies this distribution, and is available
// at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

#ifndef __CCALDATAEXCHANGE_H__ 
#define __CCALDATAEXCHANGE_H__

#include <calentry.h>

class CCalDataExchangeImpl;
class CCalSession;
class RWriteStream;

/** The default number of entries to import or export between callbacks.
@publishedAll
@released
*/
const TInt KDefaultNumberOfEntriesToHandle = 10;

/** A call back class to show the progress of long-running operations.

When a long-running operation is carried out, this class is used to signal its progress, 
and when the function is complete.

@publishedAll
@released
*/
class MCalDataExchangeCallBack
	{
public:
	/** Progress callback. 

	This calls the observing class with the percentage complete of the current operation.
	This also propagates any error to the observing class.

	@param aPercentageCompleted The percentage complete. */
	virtual void Progress(TInt aPercentageCompleted) = 0;

	/** Progress callback.

	This calls the observing class when the current operation is finished. */
	virtual void Completed() = 0;
	
	/* Retrieve the number of entries to handle at once. 
	@return The number of entries to handle at once.
	*/
	virtual TInt NumberOfEntriesToHandleAtOnce() { return KDefaultNumberOfEntriesToHandle; };
	};

/** 
This class provides functionality for importing and exporting vCal entries.
@publishedAll
@released
*/
NONSHARABLE_CLASS(CCalDataExchange) : public CBase
	{
public:
	IMPORT_C static CCalDataExchange* NewL(CCalSession& aSession);
	IMPORT_C ~CCalDataExchange();
	
	IMPORT_C void ImportL(TUid aDataFormat, RReadStream& aReadStream, RPointerArray<CCalEntry>& aCalEntryArray);
	IMPORT_C void ImportL(TUid aDataFormat, RReadStream& aReadStream, RPointerArray<CCalEntry>& aCalEntryArray, TInt aFlags);
	IMPORT_C void ExportL(TUid aDataFormat, RWriteStream& aWriteStream, RPointerArray<CCalEntry>& aCalEntryArray);	
	
	IMPORT_C void ImportL(TUid aDataFormat, RReadStream& aReadStream, RPointerArray<CCalEntry>& aCalEntryArray, TInt aFlags, TInt aNumEntries);

	IMPORT_C void ImportAsyncL(TUid aDataFormat, RReadStream& aReadStream, RPointerArray<CCalEntry>& aCalEntryArray, MCalDataExchangeCallBack& aObserver, TInt aFlags);
	IMPORT_C void ExportAsyncL(TUid aDataFormat, RWriteStream& aWriteStream, RPointerArray<CCalEntry>& aCalEntryArray, MCalDataExchangeCallBack& aObserver);
	
private:
	CCalDataExchange();
	void ConstructL(CCalSession& aSession);
	
private:
	CCalDataExchangeImpl* iImpl;
	};

#endif // __CCALDATAEXCHANGE_H__
