/*

* 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:

* Defines an ordered list of widget id's with persistence capability

*

*/

#ifndef WMPERSISTENTWIDGETORDER_H

#define WMPERSISTENTWIDGETORDER_H

// INCLUDES

#include <e32base.h>

#include "wmwidgetdata.h"

// FORWARD DECLARATIONS

class RFs;

// CLASS DECLARATION

/**

 *  CWmPersistentWidgetOrder

 * This class is an ordered list of widget identifiers. The list can be

 * serialised and extract from stream and persisted. The list can be used

 * in sorting a pointer array of CWmWidgetData.

 */

NONSHARABLE_CLASS( CWmPersistentWidgetOrder ) : public CBase

    {

public: // Constructors and destructor

    /** 

     * static constructor.

     */

    static CWmPersistentWidgetOrder* NewL( RFs& aFs );

    /** Destructor. */

    ~CWmPersistentWidgetOrder();

private: // private construction

    /**

     * constructor

     */

    CWmPersistentWidgetOrder( RFs& aFs );

    /**

     * 2nd phase constructor

     */

    void ConstructL();

public: // API

    /**

     * Loads the persistent widget list from storage.

     * This is typically done once after construction.

     * The instance can now be used to sort widget data.

     */

    void LoadL();

    /**

     * Stores a sorted array of WmWidgetData types. Note that

     * the order will be directly stored and a copy will not

     * be kept locally, so this instance can not be used to

     * sort widget data until LoadL() is called.

     * 

     * @param aArray the array of widget daya types

     */

    void StoreL( const RWidgetDataValues& aArray );

    /**

     * Retrieves an index of given widget data object within the list.

     * This index can be used to sort and organise. Note that LoadL()

     * must be used prior to calling this method, and before that

     * there must be something persisted.

     * 

     * @param aWidgetData data to seek index of in the sorted order

     * @return the index found, or KErrNotFound if widget is new

     */

    TInt IndexOf( const CWmWidgetData& aWidgetData ) const;

    /**

     * checks if the persistent widget order is empty. In this case it does

     * not make any sense to use the object to sort anything.

     * Note that before loading the object is always empty.

     */

    TBool IsEmpty() const;

protected:

    /**

     * Cleans up the array

     */

    void CleanupArray();

    /**

     * build the storage file path and name. The storage file will be located

     * in host process private directory.

     * @param aPathBuf a buffer to receive the complete file path

     */

    void GetStoreFileNameL( TDes& aPathBuf );

    /**

     * Unique tag of a widget

     */

    class Tag

        {

        public:

            /** constructs a tag from parameters */

            Tag( TInt32 aUid, HBufC16* aPublisherId );

            /** compares a tag agains a widget data */

            TBool Matches( const CWmWidgetData& aWidgetData ) const;

            /** widget uid */

            TInt32 iUid;

            /** widget publisher id */

            HBufC16* iPublisherId;

        };

private: // data members

    /** the file session */

    RFs& iFs;

    /** array of widget tags for sorting */

    RArray<Tag> iTagArray;

    };

#endif // WMPERSISTENTWIDGETORDER_H