/*

* Copyright (c) 2003 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 __VEDAUDIOCLIPINFO_H__

#define __VEDAUDIOCLIPINFO_H__

#include "VedCommon.h"

/*

 *  Forward declarations.

 */

class CVedAudioClipInfo;

/**

 * Observer for notifying that audio clip info

 * is ready for reading.

 *

 * @see  CVedAudioClipInfo

 */

class MVedAudioClipInfoObserver 

    {

public:

    /**

     * Called to notify that audio clip info is ready

     * for reading.

     *

     * Possible error codes:

     *  - <code>KErrNotFound</code> if there is no file with the specified name

     *    in the specified directory (but the directory exists)

     *  - <code>KErrPathNotFound</code> if the specified directory

     *    does not exist

     *  - <code>KErrUnknown</code> if the specified file is of unknown type

     *

     * @param aInfo   audio clip info

     * @param aError  <code>KErrNone</code> if info is ready

     *                for reading; one of the system wide

     *                error codes if reading file failed

     */

    virtual void NotifyAudioClipInfoReady(CVedAudioClipInfo& aInfo, 

                                          TInt aError) = 0;

    };

/**

 * Observer for audio clip visualization.

 *

 * @see  CVedAudioClipInfo

 */

class MVedAudioClipVisualizationObserver

    {

public:

    /**

     * Called to notify that audio clip visualization has been started. 

     * 

     * @param aInfo  audio clip info

     */

    virtual void NotifyAudioClipVisualizationStarted(const CVedAudioClipInfo& aInfo) = 0;

    /**

     * Called to inform about the current progress of the audio clip visualization.

     *

     * @param aInfo        audio clip info

     * @param aPercentage  percentage of the operation completed, must be 

       *                     in range 0..100

     */

    virtual void NotifyAudioClipVisualizationProgressed(const CVedAudioClipInfo& aInfo, 

                                                        TInt aPercentage) = 0;

    /**

     * Called to notify that audio clip visualization has been completed. 

     * Note that if the visualization was successfully completed, the ownership 

     * of the visualization array is passed to the observer and the observer is 

     * responsible for freeing the array).

     * 

     * @param aInfo           audio clip info

     * @param aError          <code>KErrNone</code> if visualization was

     *                          completed successfully; one of the system wide

     *                          error codes if generating visualization failed

     * @param aVisualization  pointer to the array containing the visualization values;

     *                        note that the ownership of the array is passed to the

     *                        observer (i.e., the observer is responsible for freeing

     *                        the array); or 0, if generating the visualization failed

     * @param aResolution     resolution of the visualization (i.e., the number of values

     *                        in the visualization array); or 0, if generating the 

     *                        visualization failed

     */

    virtual void NotifyAudioClipVisualizationCompleted(const CVedAudioClipInfo& aInfo, 

                                                       TInt aError, TInt8* aVisualization,

                                                       TInt aResolution) = 0;

    };

/**

 * Utility class for getting information about audio clip files.

 *

 */

class CVedAudioClipInfo : public CBase

    {

public:

    /* Constructors & destructor. */

    /**

     * Constructs a new CVedAudioClipInfo object to get information

     * about the specified audio clip file. The specified observer

     * is notified when info is ready for reading. This method

     * may leave if no resources are available to construct 

     * a new object.

     * 

     * Possible leave codes:

     *  - <code>KErrNoMemory</code> if memory allocation fails

     *

     * @param aFileName  name of audio clip file

     * @param aObserver  observer to notify when info is ready for reading

     *

     * @return  pointer to a new CVedAudioClipInfo instance

     */

    IMPORT_C static CVedAudioClipInfo* NewL(const TDesC& aFileName,

                                            MVedAudioClipInfoObserver& aObserver);

    /**

     * Constructs a new CVedAudioClipInfo object to get information

     * about the specified audio clip file. The constructed object

     * is left in the cleanup stack. The specified observer

     * is notified when info is ready for reading. This method

     * may leave if no resources are available to construct a new

     * object.

     * 

     * Possible leave codes:

     *  - <code>KErrNoMemory</code> if memory allocation fails

     *

     * @param aFileName  name of audio clip file

     * @param aObserver  observer to notify when info is ready for reading

     *

     * @return  pointer to a new CVedAudioClipInfo instance

     */

    IMPORT_C static CVedAudioClipInfo* NewLC(const TDesC& aFileName,

                                             MVedAudioClipInfoObserver& aObserver);

    /* Property methods. */

    /**

     * Returns the file name of the clip. Panics if info

     * is not yet ready for reading.

     * 

     * @return  file name

     */

    virtual TPtrC FileName() const = 0;

    /**

     * Returns the audio type of the clip. Panics if info

     * is not yet ready for reading.

     * 

     * @return  audio type

     */

    virtual TVedAudioType Type() const = 0;

    /**

     * Returns the duration of the clip. Panics if info

     * is not yet ready for reading.

     * 

     * @return  duration in microseconds

     */

    virtual TTimeIntervalMicroSeconds Duration() const = 0;

    /**

     * Returns the channel mode of the audio if applicable.

     *

     * @return  channel mode

     */

    virtual TVedAudioChannelMode ChannelMode() const = 0;

    /**

     * Returns the audio format of the clip. Panics if info

     * is not yet ready for reading.

     * 

     * @return  audio format of the clip

     */

    virtual TVedAudioFormat Format() const = 0;

    /**

     * Returns the sampling rate in hertz.

     *

     * @return  sampling rate

     */

    virtual TInt SamplingRate() const = 0;

    /**

     * Returns the bitrate mode.

     *

     * @return  bitrate mode

     */

    virtual TVedBitrateMode BitrateMode() const = 0;

    /**

     * Returns the bitrate.

     *

     * @return  bitrate in bits per second

     */

    virtual TInt Bitrate() const = 0;

    /* Visualization methods. */

    /**

     * Generates a visualization of the audio clip. The visualization consists

     * of an array of values with the specified resolution. This method is 

     * asynchronous. The visualization is generated in background and the observer 

     * is notified when the visualization is complete. This method panics if info 

     * is not yet ready for reading or the resolution is illegal.

     * 

     * Possible leave codes:

     *  - <code>KErrNoMemory</code> if memory allocation fails

     *

     * @param aObserver    observer to be notified when the visualization is completed

     * @param aResolution  resolution of the visualization (i.e., the number of values

     *                     in the visualization array)

     * @param aPriority    priority of the visualization

     */

    virtual void GetVisualizationL(MVedAudioClipVisualizationObserver& aObserver,

                                   TInt aResolution, TInt aPriority) = 0;

    /**

     * Cancels visualization generation. If no visualization is currently being 

     * generated, the function does nothing.

     */

    virtual void CancelVisualizationL() = 0;

    };

#endif // __VEDAUDIOCLIPINFO_H__