/*

* Copyright (c) 2006-2008 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 handler for contexts.

 *

*/

#ifndef C_CFMESSAGEHANDLERCONTEXT_H

#define C_CFMESSAGEHANDLERCONTEXT_H

#include "CFMessageHandlerBase.h"

#include "cfcontextobject.h"

#include "cfcontextsourceinterface.h"

class CCFContextIndicationImpl;

class CCFContextSubscription;

class CCFContextQuery;

class CCFContextObjectImpl;

class CCFContextSourceCommand;

/**

 * Context Framework server session message handler base class.

 */

NONSHARABLE_CLASS( CCFMessageHandlerContext ):

public CCFMessageHandlerBase,

public MCFContextSubscriptionListener, public MCFContextSource

    {

private:

    // Subscription error

    struct TSubscriptionError

        {

        TInt iError;

        CCFContextObjectImpl* iContext;

        };

public:

    // Two phased constructors

    static CCFMessageHandlerContext* NewL( MCFExtendedContextInterface& aCF,

        MCFActionInterface& aActivatorEngine,

        MCFScriptInterface& aScriptInterface );

    static CCFMessageHandlerContext* NewLC( MCFExtendedContextInterface& aCF,

        MCFActionInterface& aActivatorEngine,

        MCFScriptInterface& aScriptInterface );

    // Destructor

    ~CCFMessageHandlerContext();

protected: // From base classes

    // From CCFMessageHandlerBase

    TBool HandleMessageL( const RMessage2& aMessage );

    // From MCFContextSubscriptionListener

    void ContextIndicationL( CCFContextIndication* aIndication );

    // From MCFContextSubscriptionListener

    TInt Client( RThread& aThread ) const;

    // From MCFContextSubscriptionListener

    void HandleContextSubscriptionError( TInt aError,

        const TDesC& aSource,

        const TDesC& aType );

private: // from MCFContextSource

    // from MCFContextSource

    void Subscribers( const TDesC& aContextSource,

        const TDesC& aContextType );

    // from MCFContextSource

    void NoSubscribers( const TDesC& aContextSource,

        const TDesC& aContextType );

    // from MCFContextSource

    void HandleCommand( const CCFContextSourceCommand& aCommand );

private: // New methods

    // Publishes a context

    TInt PublishContext( CCFContextObject& aContext,

        RThread& aClientThread );

    // Adds a new subscription to CF

    TInt AddSubscription( CCFContextSubscription* aSubscription,

        RThread& aClientThread );

    // Removes subscription

    void RemoveSubscription(CCFContextSubscription& aSubscription);

    // Starts receiving context indication

    void ReceiveContextIndicationMessageL( const RMessage2& aMessage );

    // Cancels receive context indication message

    void CancelReceiveContextIndicationMessage();

    // Requests context

    TInt RequestContext( CCFContextQuery& aContextQuery,

        RThread& aClientThread );

    // Indicate subscription error

    void IndicateSubscriptionErrorL();

    // Get next indication from queue

    void CompleteNextIndicationFromQueueL( const RMessage2& aMessage );

    // Checks context indication queue

    void CheckContextIndicationQueueL();

    // Write context request buffer into stream

    void CompleteRequestContextL( const RMessage2& aMessage );

    // Handles error situations

    void DoHandleContextSubscriptionErrorL( TInt aError,

        const TDesC& aSource,

        const TDesC& aType );

private: // new message system

    void ReceiveMessageL( const RMessage2& aMessage );

    // Cancels receive message

    void CancelReceiveMessage();

    void CompleteNextMessageFromQueueL( const RMessage2& aMessage );

    void CheckMessageQueueL();

    // Leavable version from subscribers callback

    void SubscribersL( const TDesC& aContextSource, const TDesC& aContextType );

    // Leavable version from no subscribers callback

    void NoSubscribersL( const TDesC& aContextSource, const TDesC& aContextType );

    // Leavable version from handle command callback

    void HandleCommandL( const CCFContextSourceCommand& aCommand );

private:

    CCFMessageHandlerContext( MCFExtendedContextInterface& aCFContext,

        MCFActionInterface& aCFAction,

        MCFScriptInterface& aScriptInterface );

    void ConstructL();

private: // Data

    // Receive message

    RMessage2 iReceiveMessage;

    // Context request buffer

    RContextObjectArray iContextRequestBuffer;

    // Context indication queue

    RPointerArray<CCFContextIndicationImpl> iIndicationQueue;

    // Own: Subscription errors

    RArray<TSubscriptionError> iSubscriptionErrors;

    // Receive message for context source related messages

    RMessage2 iReceiveContextSourceMsg;

    // Own: array of messages to client

    RPointerArray<HBufC8> iMessageQueue;

    };

#endif