/*

* Copyright (c) 2006 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 "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:    Pubsub handler class for vcxconnectionutility*

*/

#ifndef __CVCX_CONUTILPUBSUB_H__

#define __CVCX_CONUTILPUBSUB_H__

#include <e32base.h>

#include <e32std.h>

#include <e32property.h>

class CVcxConnUtilSubscriber;

class MConnUtilPubsubObserver;

/**

* This class defines operations for handling the pub sub keys and their values.

*

*/

NONSHARABLE_CLASS( CVcxConnUtilPubSub ) : public CBase

    {	

    public: // construction / destruction

        /**

         * Construction.

         * 

         * @return The newly constructed CVcxConnUtilPubSub

         */

        static CVcxConnUtilPubSub* NewL( MConnUtilPubsubObserver *aObserver );

        /**

         * Construction. Object left to cleanupstack

         * 

         * @return The newly constructed CVcxConnUtilPubSub

         */

        static CVcxConnUtilPubSub* NewLC( MConnUtilPubsubObserver *aObserver );

        /**

         * destructor

         */

        virtual ~CVcxConnUtilPubSub();

    private:

        /**

         * C++ constructor

         */

        CVcxConnUtilPubSub(); 

        /**

         * Private 2nd phase construction.

         *

         * During instantiation, the availibility of the PS keys is being checked. In case

         * keys does not exists, they are being created by starting an external executable,

         * vcxconnutilpsworker, whose UID is being used as the unique category of the PS keys.

         * This kind of solution is needed to make sure, that category is always unique and 

         * the UID of the category is always known beforehand in vcxconnectionutility library 

         * 

         * @param aObserver observer to be passed subscribers

         */

        void ConstructL( MConnUtilPubsubObserver *aObserver );  

    public: // new functions

        /**

         * Increases a "counter" pub sub value by one.

         * If given key is not concidered as a counter,

         * nothing is done

         *  

         * @param aKey    PS key whose value to increase

         */ 

        void IncCounterPubSubL( TUint32 aKey );

        /**

         * Decreases a "counter" pub sub value by one

         * If given key is not concidered as a counter,

         * nothing is done

         *  

         * @param aKey    PS key whose value to decrease

         */ 

        void DecCounterPubSubL( TUint32 aKey ); 

        /**

         * Saves given value to the defined PS key.

         * 

         * @param aKey    PS to where to save the value

         * @param aValue  Value to save

         * 

         * @return TInt   KErrNone is succees, KerrNotFound if provided key is

         *                not in the scope of connection util or another 

         *                system level error code

         *  

         */ 

        TInt SetValue( TUint32 aKey, TInt aValue );

        /**

         * Get value from  defined PS key.

         * 

         * @param aKey    PS from where to fetch value

         * @param aValue  

         * 

         * @return TInt   KErrNone is succees, KerrNotFound if provided key is

         *                not in the scope of connection util or another 

         *                system level error code

         *  

         */ 

        TInt GetValue( TUint32 aKey, TInt& aValue );

        /**

         * Start subscribers. If using deafult value, starts all.

         * Otherwise just starts the one defined as aKey

         * 

         * @param aKey    key value of subscriber to start 

         */

        void StartSubscibers( TUint32 aKey = 0 );

        /**

         * Cancels subscribers. If using deafult value, cancels all.

         * Otherwise just cancels the one defined as aKey

         * 

         * @param aKey    key value of subscriber to cancel 

         *  

         */

        void CancelValueSubscribers( TUint32 aKey = 0 );

   private:

       /**

        * Method starts a vcxconnutilpsworker -process

        * to create PS keys for connectionutility and 

        * waits for the process to finish before returning.

        * 

        * If another process has already started worker, method

        * waits for it to finish.

        * 

        * Method leaves if existing semaphore cannot be opened or

        * creating of process fails.

        *  

        */

        void DefinePropertiesL();

        /**

         * Internal helper method to get a pointer to RProperty

         * defined by the aKey -value.

         * In case aKey refers to a property that does not exists,

         * a null pointer is returned

         * 

         * @param aKey a key value for property wanted

         * 

         * @return RProperty* pointer to property or NULL in case 

         *                    property is not found 

         */

        RProperty* GetProperty( TUint32 aKey );

        /**

         * Internal helper method to get a pointer to Subscriber

         * defined by the aKey -value.

         * In case aKey refers to a Subscriber that does not exists,

         * a null pointer is returned

         * 

         * @param aKey a key value for subscriber wanted

         * 

         * @return CVcxConnUtilSubscriber* pointer to Subscriber or NULL in case 

         *                                 property is not found 

         */

        CVcxConnUtilSubscriber* GetSubscriber( TUint32 aKey );

         /**

         * Internal helper method to handle actual incrementation or 

         * decrementation (based on the calfactor) of the PS key concidered 

         * to be a counter value in connectionutility's context.

         * 

         * @leave if PS Get or Set fails

         * 

         * @param aKey a key value for subscriber wanted

         * 

         * @param aCalcFactor a value to be added to the PS key value

         */

        void DoPSCounterIncrementL( TUint32 aKey, TInt aCalcFactor );

   private:

        /**        

         * P&S Current IAP's Id

         */

        RProperty iPropertyCurrentIAPId;

        /**

         * P&S Current Destination's Id

         */

        RProperty iPropertyCurrentSNAPId;

        /**

         * P&S telling how many instances are using connection

         */

        RProperty iPropertyNbrOfInst;

        /**

         * P&S telling how many instances 

         * have accepted roaming

         */

        RProperty iPropertyAccepted;

        /**

         * P&S telling Connection state property.

         * Object contains PS property for connection state -key and

         * subcribe -listener for that value changes

         */

        CVcxConnUtilSubscriber* iConnectionStatePS;

        /**

         * P&S telling if we currently have master instance or not

         * Object contains PS property for masterexist -key and

         * subcribe -listener for that value changes

         */

        CVcxConnUtilSubscriber* iMasterExistPS;

        /**

         * P&S telling the roaming request status from

         * the instances

         */

        CVcxConnUtilSubscriber* iRoamingReqStatusPS;

        /**

         * P&S telling the amount of connection users responded

         * roaming request

         */

        CVcxConnUtilSubscriber* iNbrInstanceResp;

        /**

         * Semaphore to protect critical counter -PS 

         * increment and decrement operations.          

         */

         RSemaphore iSemaCounter;

    };

#endif // __CVCX_CONUTILPUBSUB_H__