/*

* Copyright (c) 2007-2008 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:  message flow handling

*

*/

#ifndef _CIMCVAPPMESSAGEFLOWHANDLER_H

#define _CIMCVAPPMESSAGEFLOWHANDLER_H

//  INCLUDES

#include <e32base.h>

#include "mimcvenginemessageobserver.h"

#include "mimcvenginechatlistobserver.h"

class MIMCVEngineMessageReadInterface;

class MIMCVEngineMessageContainer;

class CIMCVEngineContextObserver;

class CIMCVEngine;

// CLASS DECLARATION

/**

*  Flow controller for messages

*

*  @imcvuiapp.exe

*  @since Series 60 5.0

*/

class CIMCVAppMessageFlowHandler : public CTimer, 

								public MIMCVEngineMessageObserver,

								public MIMCVEngineChatListObserver

    {

    public:

        /**

         * Should we fetch new messages or not

         * @param aFetch ETrue if this chat is in foreground and should 

         *               receive messages, EFalse otherwise.

         */

        void FetchMessages( TBool aFetch );        

    protected: // Functions from MIMCVEngineMessageObserver

        /**

		 * Handle events.

		 * @param aEvent Event to handle.

		 * @param aIndex, Index of message which is affected by event.

		 */

		void HandleMessageEvent( TMessageEventType aEvent, TInt aIndex );

    private:

    	/*

    	* See MIMCVEngineChatListObserver

    	*/

    	void HandleChatListEvent(TInt aServiceId, TChatListEventType aEvent, 

								MIMCVEngineMessageReadInterface* aContainerInfo  ) ;

    protected:  // Functions from CTimer

		/**

		 * @see CTimer

		 */

        void RunL();

		/**

		 * @see CActive

		 */

        TInt RunError( TInt aError );

    private:  // New functions

        /**

         * Get flow control value from settings

         */ 

        void UpdateTimeIntervalL();

        /**

         * Is opening on going or not.         

         * @return ETrue if opening on going, EFalse otherwise.

         */

        TBool IsOpening() const;

    private:

        /**

        * C++ default constructor.

        */

        CIMCVAppMessageFlowHandler(MIMCVEngineMessageContainer& aMessageContainer, 

                				   MIMCVEngineMessageReadInterface& aReadInterface,

                				   CIMCVEngine& aActiveEngine );

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL( TBool aScrollOver );

	public:  // Constructors and destructor        

		/**

         * Two-phased constructor.         

         * @param aMessageContainer Interface to UI side message container

         * @param aReadInterface Message read interface        

         * @param aScrollOver Is scroll over required 

         *                             or not.

         */

        static CIMCVAppMessageFlowHandler* NewL( 

                            MIMCVEngineMessageContainer& aMessageContainer, 

                            MIMCVEngineMessageReadInterface& aReadInterface,

                            CIMCVEngine& aActiveEngine,

                            TBool aScrollOver );

        /**

         * Destructor.

         */

        virtual ~CIMCVAppMessageFlowHandler();

    private:    // Data

        // Interface for UI side message container

        // Not owned

        MIMCVEngineMessageContainer& iMessages;

        // Interface for fetching messages

        // Not owned

        MIMCVEngineMessageReadInterface& iReadInterface;    

        CIMCVEngine& iActiveEngine;

        // time interval for receiving messages

        TTimeIntervalMicroSeconds32 iTimeInterval;

        // Is chat deleted already

        TBool iChatDeleted;

        // Should we fetch new messages

        TBool iFetchMessages;

        // Index for fetching messages

        TInt iMsgIndex;

        // Initial count for messages

        TInt iInitialMsgCount;

        // Is new message received while opening the chat

        TBool iNewMsgWhileOpening;

        // Flag is read from CR variation in class construction

        // ETrue in releases >= 3.2 

        // EFalse in releases < 3.2

        // Set to EFalse if this handler is used to handle

        // recorded chat

        TBool iBgOpeningMode;

        TInt iAddedUnreadMsgs;

    };

#endif      // _CIMCVAPPMESSAGEFLOWHANDLER_H

// End of File