/*
* Copyright (c) 2006 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:   Contains CNcdNodePreviewProxy class
*
*/


#ifndef C_NCDNODEPREVIEWPROXY_H
#define C_NCDNODEPREVIEWPROXY_H


// For the streams
#include <s32mem.h>

#include "ncdinterfacebaseproxy.h"
#include "ncdnodepreview.h"
#include "ncddownloadoperationobserver.h"

class CNcdNodeMetadataProxy;


/**
 *  This class implements the functionality for the
 *  MNcdNodeProxy interfaces. The interface is provided for
 *  API users.
 *
 *  @since S60 v3.2
 */
class CNcdNodePreviewProxy : public CNcdInterfaceBaseProxy, 
                             public MNcdNodePreview,
                             public MNcdDownloadOperationObserver
    {

public:

    /**
     * @param aSession The session between the client proxy and the
     * corresponding server object.
     * @param aHandle The handle which identifies the server object
     * that this proxy uses.
     * @param aMetadata Owns and uses the information of this proxy.
     * The node also keeps track of the refence counts of its objects. 
     * And handles the deletion of these objects when the total reference 
     * count reaches zero. 
     * @return CNcdNodePreviewProxy* Pointer to the created object 
     * of this class.
     */
    static CNcdNodePreviewProxy* NewL(
        MCatalogsClientServer& aSession,
        TInt aHandle,
        CNcdNodeMetadataProxy& aMetadata );

    /**
     * @param aSession The session between the client proxy and the
     * corresponding server object.
     * @param aHandle The handle which identifies the server object
     * that this proxy uses.
     * @param aMetadata Owns and uses the information of this proxy.
     * The node also keeps track of the refence counts of its objects. 
     * And handles the deletion of these objects when the total reference 
     * count reaches zero. 
     * @return CNcdNodePreviewProxy* Pointer to the created object 
     * of this class.
     */
    static CNcdNodePreviewProxy* NewLC(
        MCatalogsClientServer& aSession, 
        TInt aHandle,
        CNcdNodeMetadataProxy& aMetadata );


    /**
     * Destructor.
     * The destructor is set public. So, the node that owns this object may
     * delete it directly when the reference count of the node reaches zero
     * and the destructor of the node is called.
     */
    virtual ~CNcdNodePreviewProxy();


    /**
     * @return CNcdNodeMetadataProxy& Gives the metadata proxy that owns this class object.
     * @exception KNcdErrorObsolete if the object has been set as obsolete. Then, we
     * cannot be sure if the original metadata still exists because it is not the parent
     * of this class object anymore.
     */
    CNcdNodeMetadataProxy& MetadataL() const;
     

    /**
     * Gets the data for descriptors from the server side. This function is
     * called to update proxy data. The function uses the protected virtual
     * internalize functions. So, the child classes may provide their own
     * implementations for internalizations of certain metadata.
     */
    void InternalizeL();
    

public: // MNcdNodePreview

    /**
     * @see MNcdNodePreview::PreviewCount
     */ 
    TInt PreviewCount() const;
    
    /**
     * @see MNcdNodePreview::IsPreviewLoaded
     */ 
    TBool IsPreviewLoadedL( TInt aIndex ) const;
    
    /**
     * @see MNcdNodePreview::PreviewMimeType
     */ 
    const TDesC& PreviewMimeType( TInt aIndex ) const;
    
    /**
     * @see MNcdNodePreview::LoadPreviewL
     */ 
    MNcdDownloadOperation* LoadPreviewL( TInt aIndex,
        MNcdDownloadOperationObserver* aObserver );
    
    /**
     * @see MNcdNodePreview::PreviewFileL
     */ 
    RFile PreviewFileL( TInt aIndex ) const;


public: // MNcdDownloadOperationObserver

    /**
     * @see MNcdDownloadOperationObserver::DownloadProgress
     */ 
    void DownloadProgress( MNcdDownloadOperation& aOperation,
        TNcdProgress aProgress );
        
    /**
     * @see MNcdDownloadOperationObserver::QueryReceived
     */ 
    void QueryReceived( MNcdDownloadOperation& aOperation,
        MNcdQuery* aQuery );

    /**
     * @see MNcdDownloadOperationObserver::OperationComplete
     */ 
    void OperationComplete( MNcdDownloadOperation& aOperation,
        TInt aError );

protected:

    /**
     * Constructor
     *
     * @param aSession The session between the client proxy and the
     * corresponding server object.
     * @param aHandle The handle which identifies the server object
     * that this proxy uses.
     * @param aNode Owns and uses the information of this proxy.
     * The node also keeps track of the refence counts of its objects. 
     * And handles the deletion of these objects when the total reference 
     * count reaches zero.
     * @param aOperationManager This class uses operation manager to get the
     * operations for certain tasks. 
     * @return CNcdNodePreviewProxy* Pointer to the created object 
     * of this class.
     */
    CNcdNodePreviewProxy(
        MCatalogsClientServer& aSession,
        TInt aHandle,
        CNcdNodeMetadataProxy& aMetadata );

    /**
     * ConstructL
     */
    virtual void ConstructL();


    /**
     * @return TBool ETrue if this object has been set as obsolete.
     */
    TBool IsObsolete() const;
    
    /**
     * @param aObsolete ETrue if the object should be set as obsolete else EFalse.
     */
    void SetObsolete( TBool aObsolete );
        
    
    // These functions are used to update the data of this class object

    /**
     * @param aStream This stream will contain all the data content for
     * this class object. The stream is gotten from the server side. The
     * memeber variables will be updated according to the data from
     * the stream. 
     */
    virtual void InternalizeDataL( RReadStream& aStream );


private:

    // Prevent if not implemented
    CNcdNodePreviewProxy( const CNcdNodePreviewProxy& aObject );
    CNcdNodePreviewProxy& operator =( const CNcdNodePreviewProxy& aObject );
    
    
private: // data

    CNcdNodeMetadataProxy& iMetadata;
    MNcdDownloadOperationObserver* iOperationObserver;
    TBool iObsolete;
    TInt iPreviewCount;
    RPointerArray<HBufC> iPreviewMimeTypes;

    };


#endif // C_NCD_NODE_PREVIEW_PROXY_H