/*

 * 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: Telephony Multimedia Service

 *

 */

#ifndef TMS_VOLUME_EFFECT_H

#define TMS_VOLUME_EFFECT_H

#include <tms.h>

#include <tmseffect.h>

namespace TMS {

// FORWARD DECLARATIONS

class TMSVolumeEffectBody;

class TMSEffectObserver;

/**

 * TMSVolumeEffect class

 *

 * This class provides volume level control in the stream scope.

 *

 * @lib tmsapi.lib

 *

 */

class TMSVolumeEffect : public TMSEffect

    {

public:

    /**

     * Destructor

     */

    IMPORT_C virtual ~TMSVolumeEffect();

    /**

     * Add client as an observer to events generated by this object.

     *

     * This function can be called at any time. It is recommended adding

     * observer before calling any functions on the Effect. Otherwise, the

     * observer may miss a callback.

     *

     * A reference to the obsrvr is stored in the effect. EffectsEvent callback

     * will be called when an effect event occurs. When the effect instance is

     * deleted, all TMSEffectObserver references are automatically released.

     * The ownership of the obsrvr is still maintained by the client. Should

     * the client need to delete the obsrvr before deleting the effect, it

     * should remove the obsrvr reference from the effect by calling

     * RemoveObserver() function.

     *

     * @param  obsrvr

     *      Listener to be added to the effect.

     *

     * @param  user_data

     *      Any user data passed to the function.

     *

     * @return

     *      TMS_RESULT_SUCCESS if the obsrvr is successfully added to the list.

     *      TMS_RESULT_ALREADY_EXIST if the obsrvr is already in the list.

     *

     */

    IMPORT_C gint AddObserver(TMSEffectObserver& obsrvr, gpointer user_data);

    /**

     * Remove client observer from the Effect.

     *

     * This function can be called at any time.

     *

     * @param  obsrvr

     *      Listener to be removed from the effect.

     *

     * @return

     *      TMS_RESULT_SUCCESS if the obsrvr is successfully removed from the

     *      list.

     *      TMS_RESULT_DOES_NOT_EXIST if trying to remove the obsrvr that has

     *      not been added to the list.

     *

     */

    IMPORT_C gint RemoveObserver(TMSEffectObserver& obsrvr);

    /**

     * Set audio volume level. The volume level should not be higher than

     * the value returned by GetMaxLevel().

     *

     * @param  level

     *      Volume level to be set.

     *

     * @return

     *      TMS_RESULT_SUCCESS if the operation was successful.

     *

     */

    IMPORT_C gint SetLevel(const guint level);

    /**

     * Return current audio volume level settings.

     *

     * @param  level

     *      Volume level.

     *

     * @return

     *      TMS_RESULT_SUCCESS if the operation was successful.

     *

     */

    IMPORT_C gint GetLevel(guint& level);

    /**

     * Return max volume level supported by the device.

     *

     * @param  level

     *      Max volume level.

     *

     * @return

     *      TMS_RESULT_SUCCESS if the operation was successful.

     *

     */

    IMPORT_C gint GetMaxLevel(guint& level);

    /**

     * Returns type of the effect.

     *

     * This function can be called at any time.

     *

     * @param  effecttype

     *      Variable that contains the effect type on return.

     *

     * @return

     *      TMS_RESULT_SUCCESS if the operation was successful.

     *

     */

    IMPORT_C gint GetType(TMSEffectType& effecttype);

protected:

    /**

     * Constructor

     */

    IMPORT_C TMSVolumeEffect();

protected:

    TMSVolumeEffectBody *iBody;

    };

} //namespace TMS

#endif //TMS_VOLUME_EFFECT_H