/*

* 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:  Manages MCP plugins, and content publishing.

*

*/

#ifndef C_MUSICCONTENTMAP_H

#define C_MUSICCONTENTMAP_H 

#include <liwvariant.h>

#include <e32hashtab.h>

// CLASS DECLARATION

/**

* Data class to construct and hold variant values persistently.

*/

class RMusicContentVariant {

  public:

    /**

     * Constructor

     *

     * Constructs a null variant value.

     */

    RMusicContentVariant();

    /**

     * Reset variant to null value.

     * Frees content.

     */

    void Reset();

    /**

     * Set variant to integer value.

     * @param New value.

     * @return Whether the value was changed.

     * Frees content of previous value.

     */

    TBool SetL( TInt aInt);

    /**

     * Set variant to string value.

     * @param New value. An internal copy of the string is made.

     * @return Whether the value was changed.

     * Frees content of previous value.

     */

    TBool SetL( const TDesC& aDesc );

    /**

     * Set variant to map value.

     * @param New value. Reference counter of the map is increased.

     * @return Whether the value was changed.

     * Frees content of previous value.

     */

    TBool SetL( CLiwMap * aMap );

    /**

     * Check whether value has been modified since the last ResetModified.

     * @return ETrue if value has been modified.

     */

    TBool IsModified() const;

    /**

     * Reset modified flag.

     * After calling this method IsModified returns EFalse.

     */

    void ResetModified();

    /**

     * Return whether the value is null.

     * @return ETrue if value is null.

     */

    TBool IsNull() const;

    /**

     * Return the value as TLiwVariant

     * @return Value encapsulated in TLiwVariant.

     */

    TLiwVariant LiwVariant() const;

  private:

  	enum TType {ETypeNull, ETypeInt, ETypeBufC, ETypeMap};

    TType   iType; // type of the value

    TBool   iModified; // whether value has been modified

    // Data area

    union {

    	TInt      iInt;

    	HBufC   * iBufC; // owned

    	CLiwMap * iMap;  // reference counted

    } iValue;

};

// CLASS DECLARATION

/**

 *  Persistent map of variable content

 *

 *  @lib musiccontentpublisher.dll

 *  @since S60 S60 v5.0

 */

class RMusicContentMap {

  public:

    /**

     * Constructs an empty map

     */

    RMusicContentMap();

    /**

     * Resets a single value in the map in case it exists

     * @param aKey The key of the value to be reset

     * Does nothing if the value does not exist

     */

    void Reset( TPtrC8 aKey );

    /**

     * Sets a string value in the map

     * @param aKey The key of the value

     * @param aValue The value for the key. The string is copied.

     */

    void SetL( TPtrC8 aKey, const TDesC& aValue );

    /**

     * Sets an integer value in the map

     * @param aKey The key of the value

     * @param aValue The value for the key.

     */

    void SetL( TPtrC8 aKey, const TInt& aValue );

    /**

     * Sets an map value in the map

     * @param aKey The key of the value

     * @param aValue The value for the key. The reference count of the map is increased.

     */

    void SetL( TPtrC8 aKey, CLiwMap * aMap ); 

    /**

     * Check whether value has been modified since last reading the values.

     * @return ETrue if value has been modified.

     */

    TBool IsModified() const;

    /**

     * Reads all those entries from the map that have been modified

     * since previous reading of values. Null values are not read.

     *

     * @return A freshly allocated map with modified values. Null is returned if there are no modifications.

     */

    CLiwMap * GetModifiedLC ();

    /**

     * Reads all non-null entries from the map.

     *

     * @return aMap  A freshly allocated map with entries. Null is returned if map is empty.

     */

    CLiwMap * GetAllLC();

    /**

     * Closes the map discarding all its content.

     */

    void Close();

  private:

  	RMusicContentVariant& AtL (TPtrC8 aKey);

  	RHashMap<TPtrC8, RMusicContentVariant> iMap;

  	TBool                                  iModified;

};

#endif