// Copyright (c) 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:

// streammap.h: defines COpenWfcStreamMap

// 

//

#ifndef STREAMMAP_H

#define STREAMMAP_H

#include <e32base.h>

#include <e32std.h>			//for RFastLock

#include <e32hashtab.h>		//for RHashMap

class CSurfaceStream;

class TSurfaceId;

class MSurfaceUpdateServerProvider;

class CExtensionContainer;

NONSHARABLE_CLASS(COpenWfcStreamMap): public CBase

	{

	public:

		/**

		 * Returns a reference to the singleton instance.

		 * 

		 * @return	The pointer to the singleton instance

		 */

		IMPORT_C static COpenWfcStreamMap& InstanceL();

		/**

		 * Expands the array to accommodate a specified number of key-value pairs.

		 * If the hash map already has enough space for the specified number of elements, no

		 * action is taken. Any elements already in the map are retained.

		 * 

		 * @param	aExpand	The number of key-value pairs for which space should be allocated.

		 * @return	KErrNone if the operation completed aInternalVersion.

		 * @return	KErrNoMemory if sufficient memory could not be allocated.

		 */

		IMPORT_C TInt Reserve(TInt aExpand);

		/**

		 * Look up a specified TSurfaceId key in the associative array and return a pointer to the

		 * corresponding to a native stream. The reference counter of the native stream is incremented by one.

		 * 

		 * @param	aSurfaceId	The TSurfaceId key to look up

		 * @return	A pointer to the corresponding native stream, if the specified TSurfacId was found

		 * 			NULL if the look up did not succeed

		 */

		CSurfaceStream* Find(const TSurfaceId& aSurfaceId);

		/**

		 * Look up a specified TSurfaceId key in the associative array and return a pointer to the

		 * corresponding to a native stream. The reference of the native stream is incremented by one.

		 * If no native stream is found a new native stream instance is created.

		 * 

		 * @param	aSurfaceId	The TSurfaceId key to look up

		 * @return	A pointer to the corresponding native stream, if the specified TSurfacId was found

		 * 			NULL if the look up did not succeed

		 */

		CSurfaceStream* AcquireL(const TSurfaceId& aSurfaceId);

		/**

		 * Query the number of elements stored in the stream hash map.

		 * 

		 * @return	The number of the key-value pairs stored

		 */

		IMPORT_C TInt Count();

	public:

        /**

         * Register a screen number for surface update notifications.

         * 

         * @param   aScreenNum  The screen for which we enable the notification mechanism

         * @param   aPriority  The priority associated with the screen 

         * @param   aPriority  The internal version 

         * @return  KErrNone if operation is completed successfully

         */

        TInt    RegisterScreenNotifications(TInt aScreenNum, TInt aPriority,TInt aInternalVersion);

        /**

         * Retieves the screen updater associate with the specified screen

         * 

         * @param   aScreenNum  The screen number

         * @return  Pointer to screen updater id successful or NULL otherwise

         */

        CExtensionContainer*    RegisteredScreenNotifications(TInt aScreenNum);

        /**

         * Unregister the screen updater

         * 

         * @param   aScreenNum  The screen number

         * @return  KErrNone if operation is completed successfully

         */

        TInt    UnregisterScreenNotifications(TInt aScreenNum);

		/**

		 * Returns a reference to the surface manager.

		 * 

		 * @return	A reference to the local SurfaceManager

		 */

		RSurfaceManager& SurfaceManager();

        /**

         * Returns a pointer to the main heap

         * 

         * @return  A pointer to the main heap

         */

		IMPORT_C RHeap* GetMainHeap();

        /**

         * Sets the main heap

        */

		void SetMainHeap();

	protected:

		friend class CSurfaceStream;

		/**

		 * Destroys the specified native stream IF the native stream reference counter is zero.

		 * The counter reference of the native stream is tested prior its destruction and

		 * if positive the destruction will not happen

		 * 

		 * @param	aStream	The stream to be destroyed

		 * @return	KErrNone if the native stream is removed

		 * 			KErrArgument if the parameter is invalid

		 * 			KErrInUse if the stream has a owner

		 * 			KErrNotFound if the TSurfaceId key was not found

		 */

		TInt LockDestroy(CSurfaceStream* aStream);

		/**

		 * Constructor

		 */

		COpenWfcStreamMap();

		/**

		 * Destructor.

		 */

		~COpenWfcStreamMap();

	private:		

		/**

		 * Auxilliary private class to insure the release of a lock

		 */

		class Guard

			{

			public:

			Guard(RFastLock& aLock);

			~Guard();

			private:

				RFastLock& iLock;

			};

	private:

		/**

		 * Copy constructor

		 */

		COpenWfcStreamMap(const COpenWfcStreamMap&);

		/**

		 * Assignment operator

		 */

		COpenWfcStreamMap& operator= (const COpenWfcStreamMap&);

		/**

		 * Symbian constructor used with two stage construction pattern

		 */

		void ConstructL();

		/**

		Forms a 32-bit hash value from a TSurfaceId.

		@param aHashKey The 64-bit key to be hashed.

		@return 32-bit hash value.

		*/

		static TUint32 HashFunction(const TSurfaceId& aHashKey);

		static TInt COpenWfcStreamMap::DeleteSingleton(TAny* aData);

	private:

		/**

		 * Mutex used for controlling the access to the native streams map

		 */

		RFastLock iMutex;

		/**

		 * Native stream map

		 */

		RHashMap<TSurfaceId, CSurfaceStream*> iMap;

		/**

		 * Initial HashMap size

		 */

		static const TInt iInitialSize = 0;

		/**

		 * Singleton instance placeholder

		 */

		static COpenWfcStreamMap* pInstance;

		/**

		 * Surface manager

		 */

		RHeap *iMainHeap; //< --This points to main thread's heap--

		RHashMap<TInt32, CExtensionContainer*>	iRegisteredUpdaters; //< Proxy objects for handing surface update notifications.

		MSurfaceUpdateServerProvider*   iSurfUpdateServ;    // Pointer to the surface update server

	};

#endif /* STREAMMAP_H */