/*

* Copyright (c) 2005 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:  Group for equalizer controls

*

*/

#ifndef CAMMSEQUALIZERCONTROLGROUP_H

#define CAMMSEQUALIZERCONTROLGROUP_H

//  INCLUDES

#include <e32base.h>

#include "cammseffectcontrolgroup.h"

#include <AudioEqualizerData.h>

// CONSTANTS

_LIT(KAMMSEqualizerControlClassName,

     ".amms.control.audioeffect.EqualizerControl");

// FORWARD DECLARATIONS

class CAMMSBaseEqualizerControl;

class CAudioEqualizerUtility;

// CLASS DECLARATION

/**

 *  Group for equalizer controls

 *

 *  @since 3.0

 */

NONSHARABLE_CLASS(CAMMSEqualizerControlGroup): public CAMMSEffectControlGroup

{

public:  // Constructors and destructor

    /**

     * Two-phased constructor.

     */

    static CAMMSEqualizerControlGroup* NewLC();

    /**

     * Destructor.

     */

    ~CAMMSEqualizerControlGroup();

public: // New functions

    /**

     * Gets the band that has the most effect on the given frequency

     *

     * @param aFrequency    The frequency in milliHertz which is

     *                      to be equalized via the returned band

     *

     * @return The frequency band that has most effect on the given

     * frequency or -1 if no band has effect on the given frequency

     */

    TInt Band(TInt aFrequency);

    /**

     * Gets the gain set for the given equalizer band.

     *

     * @param aBand         The frequency band whose gain is asked.

     * @param aBandLevel    The returned level for the given band in millibels.

     *

     */

    void GetBandLevelL(TInt aBand, TInt& aBandLevel);

    /**

     * Gets the bass level.

     *

     * @return The current level that is set to the bass band. If the

     * bass level cannot been defined EqualizerControl.UNDEFINED will

     * be returned

     */

    TInt Bass();

    /**

     * Gets the center frequency of the given band

     *

     * @param aBand         The frequency band whose center frequency

     *                      is asked.

     * @param aCenterFreq   The returned center frequency in milliHertz.

     */

    void GetCenterFreqL(TInt aBand, TInt& aCenterFreq);

    /**

     * Returns the maximum band level supported

     *

     * @return the maximum band level supported

     */

    TInt MaxBandLevel();

    /**

     * Returns the minimum band level supported.

     *

     * @return the minimum band level supported.

     */

    TInt MinBandLevel();

    /**

     * Gets the number of frequency bands that the equalizer supports.

     *

     * @return the number of frequency bands that the equalizer supports.

     */

    TInt NumberOfBands();

    /**

     * Gets the treble level.

     *

     * @return The current level that is set to the treble band. If the

     * treble level cannot been defined EqualizerControl.UNDEFINED will

     * be returned

     */

    TInt Treble();

    /**

     * Sets the given equalizer band to the given gain value.

     *

     * @param aLevel    The new gain in millibels that will be set to the

     *                  given band

     * @param aBand     The frequency band that will have the new gain

     */

    void SetBandLevelL(TInt aLevel, TInt aBand);

    /**

     * Sets the bass level using a linear point scale with values between

     * 0 and 100: a value of 0 applies the maximum available attenuation

     * to frequencies in the bass band; a value of 50 gives a flat

     * equalization of the bass band; and a value of 100 applies the

     * maximum available amplification to frequencies in the bass band.

     *

     * @param aLevel    The new level on a linear point scale that will

     *                  be set to the bass band

     * @param aSetLevel Returned level that was actually set

     */

    void SetBassL(TInt aLevel, TInt& aSetLevel);

    /**

     * Sets the treble level using a linear point scale with values between

     * 0 and 100: a value of 0 applies the maximum available attenuation to

     * frequencies in the treble band; a value of 50 gives a flat

     * equalization of the treble band; and a value of 100 applies the

     * maximum available amplification to frequencies in the treble band

     *

     * @param aLevel    The new level on a linear point scale that will

     *                  be set to the treble band

     *

     * @param aSetLevel Returned level that was actually set

     */

    void SetTrebleL(TInt aLevel, TInt& aSetLevel);

private: // New functions

    /**

     * Gets control. Ownership is not tranferred.

     *

     * @param aIndex Control index.

     */

    CAMMSBaseEqualizerControl* TypeSafeControl(TInt aIndex) const;

    /**

     * Checks whether the band index is between 0 and number of bands -1.

     * Function leaves with KErrArgument if the band is not between the

     * limits.

     */

    void CheckBandIndexL(TInt aBand) const;

    /**

     * Gets bands corresponding to the given preset index.

     * The data is obtained from controls (or from empty group utility, if the

     * group has no controls).

     * @param aPresetIndex Index of the preset whose bands are asked

     * @param aBands Returned bands

     */

    void GetPresetBandsL(TUint aPresetIndex,

                         RArray< TEfAudioEqualizerBand >& aBands);

public: // Functions from base classes

    /**

     * Returns class name that identifies this control group.

     *

     * @return Control group name.

     */

    const TDesC16& ClassName();

protected: // Functions from base classes

    /**

     * Called by when a new player is added

     *

     * @param aPlayer   The player being added

     * @param aControl  The player's control relevant to this group

     */

    void NotifyPlayerAddedL(CMMAPlayer *aPlayer, CMMAControl* aControl);

    /**

     * Called when the current preset changes

     */

    void PresetChangedL();

    /**

     * Finish initialization (after the 1st player is added)

     */

    void InitializeL();

    /**

     * Creates utilities that can be used to obtain preset names

     * and preset data (needed when the group has no controls).

     * Does nothing if the utility already exists.

     */

    void PrepareEmptyGroupUtilitiesL();

    /**

     * Deletes utilities that are used to obtain preset names

     * and preset data (needed when the group has no controls).

     * Does nothing if the utilities have already been deleted.

     */

    void DeleteEmptyGroupUtilities();

    /**

     * Gets list of preset names available.

     * @param aPresetNames Returned preset names

     */

    void GetPresetNamesL(CDesCArray& aPresetNames);

protected:

    /**

     * C++ default constructor.

     */

    CAMMSEqualizerControlGroup();

    /**

     * By default Symbian 2nd phase constructor is private.

     */

    void ConstructL();

private: // data

    // Needed to get preset names when the group has no controls.

    CAudioEqualizerUtility* iEmptyAudioEqualizerUtility;  // Owned.

    RArray< TEfAudioEqualizerBand > iBands;

    TInt iBass; // bass level

    TInt iTreble; // treble level

    TInt iMaxBandLevel;

    TInt iMinBandLevel;

};

#endif // CAMMSEQUALIZERCONTROLGROUP_H