/*

* Copyright (c) 2008 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:    data source header file

*

*/

#ifndef _C_GLXDATASOURCE_H_

#define _C_GLXDATASOURCE_H_

// INCLUDES

#include <e32base.h>

#include <e32cmn.h>

#include <mpxattribute.h>

#include <mpxcollectionpath.h>

#include <ecom/ecom.h>

#include "mglxdatasource.h"

// FORWARD DECLARATIONS

class CGlxRequest;

class CGlxDataSourceTask;

class CGlxDataSource;

// CONSTANTS

// CLASS DECLARATION

/**

 * CDataSourceArrayOwner

 * A singleton that owns a pointer array of datasources

 */

NONSHARABLE_CLASS(CDataSourceArrayOwner) : public CBase

    {

public:

	/**

	 * Returns the CDataSourceArrayOwner singleton

	 * @return the CDataSourceArrayOwner singleton

	 */

    static CDataSourceArrayOwner* InstanceL();

    /**

     * Closes the singleton

     */

    void Close();

    /**

     * Retuns a reference to the array owned by this object

     * @return a reference to the array owned by this object

     */

    RPointerArray<CGlxDataSource>& Array();

private:

	/**

	 * Constructor (private so that only

	 * the singleton store can use it)

	 */

    static CDataSourceArrayOwner* NewL();    

    /**

     * Destructor

     */

    ~CDataSourceArrayOwner();

private:

      /**

       * Array of datasource

       * (owned)

       * (array contents not owned)

       */

      RPointerArray<CGlxDataSource> iDataSources;

      };

/**

 *  CGlxDataSource class 

 *

 *  Data Source is the Data Source base class.

 *	@ingroup collection_component_design

 *  @internal reviewed 11/07/2007 by Dave Schofield

 */

class CGlxDataSource : public CActive,

					   public MGlxDataSource

	{

public:

	IMPORT_C CGlxDataSource();

    IMPORT_C virtual ~CGlxDataSource();

public: // from MGlxDataSource

	/**

	 * Asynchronous call to retrieve 

	 * 

	 * @param aListId list for this query relates to

	 * @return error code

	 */

	IMPORT_C void DataSourceRequestL(CGlxRequest* aRequest, MGlxDataSourceRequestObserver& aObserver);

	/**

	 * Cancel asynchronous request call

	 * as each requestor can only have one active request the observer is sufficient to cancel the request.

	 * 

	 */

	IMPORT_C void CancelRequest(MGlxDataSourceRequestObserver& aObserver);

	/**

	 * Decrements the reference count of the data source. Deletes the 

	 * data source if there are no more references.

	 */

	IMPORT_C void Close(MGlxDataSourceUpdateObserver& aObserver);

public:

    IMPORT_C void HandleTaskComplete(CGlxDataSourceTask* aRequest);

public:

	inline const TUid& Uid() const

		{

		return iUid;

		};

	inline void SetUid(const TUid& aUid)

		{

		iUid = aUid;

		};

	inline const TInt Count() 

		{

		return iDataSourceObservers.Count();

		};

	inline void SetDtorKey(const TUid& aDtorKey)

		{

		iDtorKey = aDtorKey;

		};

	inline void SetEComSession(REComSession& aEComSession)

		{

		iEComSession = aEComSession;

		};

	/**

	 * Set the datasource array owner

	 * Should be called after object construction

	 * @param aDataSourceArrayOwner the datasource array owner

	 */

	inline void SetDataSourceArrayOwner(CDataSourceArrayOwner* aDataSourceArrayOwner)

		{

		iDataSourceArrayOwner = aDataSourceArrayOwner;

		};

public:

	void AddObserverL(MGlxDataSourceUpdateObserver& aObserver);

public: // from CActive

    IMPORT_C void RunL();

    IMPORT_C void DoCancel();

    IMPORT_C TInt RunError(TInt aError);

public:

	enum TItemType

		{

		EItemTypeNotAnItem = 0,

		EItemTypeImage,

		EItemTypeVideo

		};

	enum TContainerType

		{

		EContainerTypeNotAContainer = 0,

		EContainerTypeAlbum,

		EContainerTypeTag,

		EContainerTypeMonth

		};

private:

    enum TAction

    {

        EExecuteOnly = 1,

        ECleanupAndExecute

    };

private:

	virtual CGlxDataSourceTask* CreateTaskL(CGlxRequest* aRequest, MGlxDataSourceRequestObserver& aObserver) = 0;

	void CompleteSelf(TAction aAction);

	virtual void TaskStartedL() = 0;

	virtual void TaskCompletedL()= 0;

protected:

	IMPORT_C void BroadcastMessage(CMPXMessage& aMessage);

	IMPORT_C void TryStartTask(TBool aFirstStart = EFalse);

protected:

	RPointerArray< MGlxDataSourceUpdateObserver > iDataSourceObservers;

	RPointerArray< CGlxDataSourceTask > iTasks;

	TInt iDataSourceId; // session specific id count from DSM, used to mask the item ids.

	TInt iCount;

	TUid iUid;

	TUid iDtorKey;

	REComSession iEComSession;

	TBool iDataSourceReady;

	/**

	 * Singleton, reference counted

	 * Close() should be called when in order

	 * when object is no longer required.

	 */

	CDataSourceArrayOwner* iDataSourceArrayOwner;

	};

#endif //_C_GLXDATASOURCE_H_