/*

* Copyright (c) 2002 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:  Concrete interface for loading thumbail images.

*

*/

#ifndef CPHCNTTHUMBNAILLOADERIMPL_H

#define CPHCNTTHUMBNAILLOADERIMPL_H

// INCLUDES

#include    "cphcntthumbnailloader.h"

#include    "mphcntthumbnailloader.h"

// FORWARD DECLARATIONS

class MPhoneCntPbkOwner;

class MPhCntThumbnailLoaderObserver;

class CPbkContactItem;

class CPbkThumbnailManager;

class MPbkThumbnailOperation;

class CPhCntContactId;

// CLASS DECLARATION

/**

*  It loads thumbail images.

*

*  Note that it is considered that loading of thumbnail images is not critical.

*  Thus, if something fails during loading procedure, then we ignore the whole 

*  thumbnail.

*

*  However, observer will be informed of both success and failure.

*

*  @lib PhoneCntFinder

*  @since 1.0

*/

NONSHARABLE_CLASS( CPhCntThumbnailLoaderImpl )

    : public CPhCntThumbnailLoader,

      private MPhCntLoaderObserver

    {

    public:  // Constructors and destructor      

        /**

        * Two-phased constructor.

        */

        static CPhCntThumbnailLoaderImpl* NewL(

            MPhCntThumbnailLoaderObserver& aObserver,

            MPhoneCntPbkOwner& aPbkOwner,

            MPhCntThumbnailLoader& aLoader );

        /**

        * Destructor.

        */

        ~CPhCntThumbnailLoaderImpl();

    public: // Functions from base classes

        /**

        * From CPhCntThumbnailLoader

        */

        TInt Load( TThumbnailId& aId, const CPhCntContactId& aContactId );

        /**

        * From CPhCntThumbnailLoader

        */

        void Cancel( TThumbnailId aId );

        /**

         * Indication that loading has been made.

         * 

         * @since S60 v3.0

         * @param Pointer of bitmap loaded, ownership is given to caller.

         * May be null if error occured during loading.

         * @param aError Error code of loading.

         */

        void LoadingCompleted( CFbsBitmap* aBitmap, TInt aError );

    private:

        /**

        * It contains necessary information to load a thumbnail.

        */

        struct TThumbnailInfo

            {

            // It contains index.

            TThumbnailId iId;

            // Identifies the contact, which thumbnail is going to be loaded.

            CPhCntContactId* iContactId;

            };

        /**

        * It enumerates all states.

        */

        enum TState

            {

            ELoadFromContact,

            EProcessResult

            };

        /**

        * C++ constructor.

        */

        CPhCntThumbnailLoaderImpl(

            MPhCntThumbnailLoaderObserver& aObserver,

            MPhoneCntPbkOwner& aPbkOwner,

            MPhCntThumbnailLoader& aLoader );

        /**

        * Symbian OS constructor.

        */

        void ConstructL( MPhoneCntPbkOwner& aPbkOwner );

        /**

        * Attempts to start loading of thumbnail.

        */

        void AttemptLoadL( 

            TThumbnailId aId, 

            const CPhCntContactId& aContactId );

        /**

        * Starts loading next thumbnail.

        */

        void StartLoadL();

        /**

        * Cancels loading.

        */

        void CancelLoad();

        /**

        * Processes the result.

        */

        void ProcessResultL();

        /**

        * Finds position in array by thumbnail id.

        *

        * @param aId id.

        * @return position or KErrNotFound if not found.

        */

        TInt FindById( TThumbnailId aId );

        /**

        * Starts loading. If it failed, then simply inform

        * observer about failure.

        */

        void DoStartLoad();

        /**

        * Handles start.

        */

        void HandleStartL();

        /**

        * Handles start; calls HandleStartL in trap harnness.

        */

        void HandleStart();

        /**

        * Starts bridge.

        */ 

        void Start( TState aState );

        /**

        * Idle callback.

        */

        static TInt DoStart( TAny* aAny );

        /**

        * It gives thumbnail to the observer.

        *

        * Ownership of the bitmap is transferred to the client.

        *

        * @param aResult error code.

        * @param aBitmap bitmap or NULL if no bitmap loaded.

        */

        void Notify( 

            TThumbnailId aId, 

            TInt aResult, 

            CFbsBitmap* aBitmap );

        /**

        * Clears all pbk stuff.

        */

        void ClearPbk( TBool aMore = ETrue );

        /**

        * Compares ids of two structure.

        *

        * @return ETrue iff aFirst.iId == aSecond.iId.

        */

        static TBool CompareIds( 

            const TThumbnailInfo& aFirst,

            const TThumbnailInfo& aSecond );

        /**

        * It is enumeration of all panic reasons.

        */

        enum TPanicReason

            {

            EPanicInvariant,

            EPanicInvalidState

            };

        /**

        * Panics.

        *

        * @param aReason reason for panic.

        */

        static void Panic( TPanicReason aReason );

        void ClearThumbnailArray();

        void RemoveThumbnailArrayEntry( TInt aIndex );

    private:    // Data

        /**

        * It is type for array of thumbnail info.

        */

        typedef RArray< TThumbnailInfo > RThumbnailArray;

        // Ref: Observer.

        MPhCntThumbnailLoaderObserver& iObserver;       

        // Owned: array of thumbnails to load.

        RThumbnailArray iArray;

        // Owned: active bridge

        CIdle* iBridge;

        // INFORMATION OF LOADING..

        // Current state.

        TState iState;

        // Currently loading. System is loading iff iCurrent != KNullId.

        TThumbnailId iCurrent;                

        // Current bitmap.

        CFbsBitmap* iBitmap;

        /**

         * Thumbnail loader.

         * Own.

         */

        MPhCntThumbnailLoader* iLoader;

    };

#endif      // CPHCNTTHUMBNAILLOADERIMPL_H

// End of File