/*

* Copyright (c) 2008-2008 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:   Base class for the signal level handling

*

*/

#ifndef VCCSIGNALLEVELHANDLER_H

#define VCCSIGNALLEVELHANDLER_H

#include <e32base.h>

#include "vccsignallevelobserver.h"

#include "vccunittesting.h"

#include "vccsignallevelparams.h"

/**

 *  Base class for signal level handling.

 *  Other classes are derived from this class.

 *

 *  @code

 *

 *  class CVccXXXSignalLevelHandler : public CVccSignalLevelHandler,

 *                                    public MXXXOtherClass

 *

 *  @endcode

 *

 *  @lib vcchotrigger.dll

 *  @since S60 v3.2

 */

class CVccSignalLevelHandler : public CTimer

    {

private:

    /** Level of the signal */

    enum TStrengthState

        {

        EStrengthUnknown,

        EStrengthLow,

        EStrengthHigh

        };

    /** Current operation mode */

    enum TOperation

        {

        EOperationNone,

        EOperationGet,

        EOperationWait,

        EOperationComplete

        };

public:

    /**

    * Destructor.

    */

    virtual ~CVccSignalLevelHandler();

    /**

     * Start signal level observing

     *

     * @since S60 3.2

     */

    void StartL();

    /**

     * Stop signal level observing

     *

     * @since S60 3.2

     */

    void Stop();

    /**

     * Set the notification parameters

     *

     * @since S60 3.2

     * @param aParams Notification parameters

     */

    virtual void SetParams( const TSignalLevelParams& aParams );

protected:

    /**

     * C++ constructor

     *

     * @since S60 3.2

     * @param aObserver Observer to be notified when signal level changes

     * @param aParams Parameters at which level notifications should be given

     * as well the timeout how long the signal must at the specified level or

     * above before notification is given.

     */

    CVccSignalLevelHandler(

            MVccSignalLevelObserver& aObserver,

            const TSignalLevelParams& aParams );

    /**

     * Get the current Received Signal Strength Indicator (RSSI)

     *

     * @since S60 3.2

     */

    virtual void GetStrength() = 0;

    /**

     * Activate the notification service

     *

     * @since S60 3.2

     */

    virtual void EnableNotificationsL() = 0;

    /**

     * Cancel the notification service

     *

     * @since S60 3.2

     */

    virtual void DisableNotifications() = 0;

    /**

     * Cancel outstanding signal strentgh request.

     *

     * @since S60 3.2

     */

    virtual void CancelGetStrength() = 0;

    /**

     * Notifies the observer about signal level changes.

     *

     * @since S60 3.2

     * @param aRss RSS level in absolute dBm values

     * @param aRssClass specifies the current class of the received signal

     */

    virtual void NotifyChanges( TInt32 aSignalStrength,

         MVccSignalLevelObserver::TSignalStrengthClass aClass ) = 0;

    /**

     * Handles singal strength changes which are notified by the signal level observer

     *

     * @since S60 3.2

     */

    void StrengthChanged();

// from base class CTimer

    /**

     * @see CTimer::ConstructL()

     */

    void ConstructL();

    /**

     * From CTimer::DoCancel()

     */

    void DoCancel();

private:

// from base class CActive

    /**

     * From CActive::RunL()

     */

    void RunL();

protected: // data

    /**

     * Observer

     * Not own

     */

    MVccSignalLevelObserver& iObserver;

    /**

     * Parameters defining timers and signal levels

     */

    TSignalLevelParams iParams;

    /**

     * Current signal level in dBm

     */

    TInt32 iStrength;

private: // data

    /**

     * Flag to determine if the observing/notifications are on or off

     */

    TBool iNotificationsOn;

    /**

     * Current signal state

     */

    TStrengthState iState;

    /**

     * Current operation

     */

    TOperation iOperation;

    VCC_UNITTEST( UT_CVccWlanSignalLevelHandler )

    VCC_UNITTEST( UT_CVccGsmSignalLevelHandler )

    };

#endif // VCCSIGNALLEVELHANDLER_H