/*

* 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:

*

*/

#ifndef CRADIOPROPERTYOBSERVER_H

#define CRADIOPROPERTYOBSERVER_H

#include <e32base.h>

#include <e32property.h>

/**

 * MRadioPropertyChangeObserver

 *

 * Abstract interface for handling property change events.

 */

class MRadioPropertyChangeObserver

{

public:

    /**

     * This is a callback function which is called when a property value of

     * type int is changed.

     *

     * @param aCategory UID of Publish And Subscribe category

     * @param aKey subkey to specify the category event; to be used with

     * Publish And Subscribe

     *

     * @param aValue the new value

     */

    virtual void HandlePropertyChangeL(

        const TUid& aCategory,

        const TUint aKey,

        const TInt aValue ) = 0;

    /**

     * This is a callback function which is called when a property value of

     * type byte array is changed.

     *

     * @param aCategory UID of Publish And Subscribe category

     * @param aKey subkey to specify the category event; to be used with

     * Publish And Subscribe

     * @param aValue the new value

     **/

    virtual void HandlePropertyChangeL(

        const TUid& aCategory,

        const TUint aKey,

        const TDesC8& aValue ) = 0;

    /**

     * This is a callback function which is called when a property value of

     * type text is changed.

     *

     * @param aCategory UID of Publish And Subscribe category

     * @param aKey subkey to specify the category event; to be used with

     * Publish And Subscribe

     * @param aValue the new value

     **/

    virtual void HandlePropertyChangeL(

        const TUid& aCategory,

        const TUint aKey,

        const TDesC& aValue ) = 0;

    /**

     * This is a callback function which is called when a P&S components

     * returns an error

     *

     * @param aCategory UID of Publish And Subscribe category

     * @param aKey subkey to specify the category event

     * @param aError an error code

     */

    virtual void HandlePropertyChangeErrorL(

        const TUid& aCategory,

        const TUint aKey,

        TInt aError ) = 0;

};

/**

 * Observer class that observes changes of Property values and propogates

 * them further.

 * The class defines a handle to a property, a single data value representing

 * an item of state information.

 *

 */

NONSHARABLE_CLASS( CRadioPropertyObserver ) : public CActive

    {

 public:

    /**

     * Property type. Cannot use RProperty::TType because EByteArray == EText.

     */

    enum TRadioPropertyType

        {

        ERadioPropertyInt, // Integral property type.

        ERadioPropertyByteArray, // Byte-array ( 8 bit ), max size 512 bytes

        ERadioPropertyText // Text ( 16 bit ), max size 512 bytes

        };

    /**

     * Two-phased constructor.

     *

     * @param aObserver a reference to the observer interface implementer

     * @param aCategory UID of Publish And Subscribe category

     * @param aKey subkey to specify the category event; to be used with

     * Publish And Subscribe

     * @param aPropertyType property type to observe

     */

    IMPORT_C static CRadioPropertyObserver* NewL(

        MRadioPropertyChangeObserver& aObserver,

        const TUid& aCategory,

        const TUint aKey,

        const TRadioPropertyType aPropertyType );

    ~CRadioPropertyObserver();

    /**

     * Subscribes the object to listen to the specified key. Does nothing if already active.

     * Must be called after construction, or after calling Cancel().

     */

    IMPORT_C void ActivateL();

    /**

     * Returns current integer property value

     *

     * @return int value

     */

    IMPORT_C TInt ValueInt() const;

    /**

     * Returns current byte array property value

     *

     * @return byte array value

     */

    IMPORT_C const TDesC8& ValueDes8() const;

    /**

     * Returns current text property value

     *

     * @return text value

     */

    IMPORT_C const TDesC& ValueDes() const;

private:

    /**

     * C++ default constructor overload.

     * Two-phased constructor.

     *

     * @param aObserver a reference to the observer interface implementer

     * @param aCategory UID of Publish And Subscribe category

     * @param aKey subkey to specify the category event; to be used with

     * Publish And Subscribe

     * @param aPropertyType property type to observe

     */

    CRadioPropertyObserver(

        MRadioPropertyChangeObserver& aObserver,

        const TUid& aCategory,

        const TUint aKey,

        const TRadioPropertyType aPropertyType );

    /**

     * By default Symbian 2nd phase constructor is private.

     **/

    void ConstructL();

protected:

    // from base class Cactive

    /**

     * From CActive

     *

     * @see CActive::RunL()

     */

    void RunL();

    /**

     * From CActive,

     *

     * @see CActive::DoCancel()

     */

    void DoCancel();

private: // data

    /**

     * Value of a subscribed category property of type int.

     */

    TInt                            iValueInt;

    /**

     * Value of a subscribed category property of type byte array.

     */

    HBufC8*                         iValueByteArray;

    /**

     * Value of a subscribed category property of type text.

     */

    HBufC*                          iValueText;

    /**

     * Handle to Publish And Subscribe component

     */

    RProperty                       iProperty;

    /**

     * Observer to be notified when particular Property value has changed

     */

    MRadioPropertyChangeObserver&   iObserver;

    /**

     * UID of Publish And Subscribe category

     */

    TUid                            iCategory;

    /**

     * Subkey to be used with Publish And Subscribe

     */

    TUint                           iKey;

    /**

     * Type of the observed property.

     */

    TRadioPropertyType              iPropertyType;

    };

#endif  // CRADIOPROPERTYOBSERVER_H