/*

* Copyright (c) 2007 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:      Resolver for remote items

*

*/

#ifndef UPNPREMOTEITEMRESOLVER_H

#define UPNPREMOTEITEMRESOLVER_H

//  INCLUDES

#include <e32base.h>

#include "upnpitemresolver.h" // base class

#include "upnpabstractbrowsingsessionobserver.h" // base class

// FORWARD DECLARATIONS

class MUPnPAVBrowsingSession;

class CUpnpItem;

class CUpnpElement;

class MUPnPResourceSelector;

// CLASS DECLARATION

/**

* Resolves remote upnp items from a plain item id.

* This resolving is done by executing a upnp metadata browse, or

* possibly several ones of those.

*

* @lib upnpavcontrollerhelper.lib

* @since S60 3.2

*/

class CUPnPRemoteItemResolver

    : public CUPnPAbstractBrowsingSessionObserver

    , public MUPnPItemResolver

    {

public: // construction/destruction

    /**

     * static constructor.

     *

     * @since Series 60 3.2

     * @param aItemId, item to be resolved

     * @param aHostSession, browsing session

     * @param aSelector, resource selector

     * @param aBrowseFilter, filter

     * @return RemoteItemResolver instance 

     */

    static CUPnPRemoteItemResolver* NewL(

        const TDesC8& aItemId,

        MUPnPAVBrowsingSession& aHostSession,

        MUPnPResourceSelector& aSelector,

        const TDesC8& aBrowseFilter );

    /**

     * destructor

     * @since Series 60 3.2

     */

    virtual ~CUPnPRemoteItemResolver();

private: // private construction part

    /**

     * default constructor.

     *

     * @since Series 60 3.2

     * @param aItemId, item to be resolved

     * @param aHostSession, browsing session

     * @param aSelector, resource selector

     * @param aBrowseFilter, filter

     */

    CUPnPRemoteItemResolver(

        const TDesC8& aItemId,

        MUPnPAVBrowsingSession& aHostSession,

        MUPnPResourceSelector& aSelector,

        const TDesC8& aBrowseFilter );

    /**

     * 2nd phase constructor.

     *

     * @since Series 60 3.2

     * @param aItemId, item to be resolved

     * @param aHostSession, browsing session

     * @param aSelector, resource selector

     * @param aBrowseFilter, filter

     */

    void ConstructL(

        const TDesC8& aItemId,

        MUPnPAVBrowsingSession& aHostSession,

        MUPnPResourceSelector& aSelector,

        const TDesC8& aBrowseFilter );

public: // the interface

    /**

     * see UPnPItemResolver

     */

    void ResolveL(

        MUPnPItemResolverObserver& aObserver );

    /**

     * see UPnPItemResolver

     */

    const CUpnpItem& Item() const;

    /**

     * see UPnPItemResolver

     */

    const CUpnpElement& Resource() const;

protected: // MUPnPAVBrowsingSessionObserver

    /**

     * see MUPnPAVBrowsingSessionObserver

     */

    void BrowseResponse(

        const TDesC8& aBrowseResponse,

        TInt aError,

        TInt aMatches,

        TInt aTotalCount,

        const TDesC8& aUpdateId

        );

private: // private methods

    /**

     * after receiving the result object, processes it:

     * either continues browsing recursively or calls back

     * notifying the object is ready to be fetched.

     */

    void ProcessResultObjectL( const CUpnpObject* aResult );

    /**

     * Completes ongoing async operation

     */

    void Complete( TInt aError );

    /**

     * Clean up all resources

     */

    void Cleanup();

    /**

     * internal state machinery

     */

    enum TInternalState {

        EStateIdle,    // no data, ready for starting

        EStateActive,  // browsing for data

        EStateReady    // Data exists

    };

    /**

     * Handles the parsing of the browse response.

     *

     * @since S60 3.2

     * @param aBrowseResponse (const TDesC8&) the browse response

     */

    void BrowseResponseL( const TDesC8& aBrowseResponse );

private: // members

    // item to resolve (Owned)

    HBufC8* iItemId;

    // the host browsing session

    MUPnPAVBrowsingSession& iBrowsingSession;

    // selector interface to use

    MUPnPResourceSelector& iSelector;

    // filter used in browse

    const TDesC8& iBrowseFilter;

    // observer for the resolver. NOT OWNED

    MUPnPItemResolverObserver* iObserver;

    // state of the class

    TInternalState iState;

    // counter for browse resursion

    TInt iRecursionDepth;

    // the first level browse result item (Owned).

    CUpnpItem* iFirstLevelItem;

    // optional: last level browse result item, if first level

    // is a pointer object (Owned). 

    CUpnpItem* iLastLevelItem;

    // The selected resource within the last level item. NOT OWNED

    const CUpnpElement* iResource;

    };

#endif  // UPNPREMOTEITEMRESOLVER_H

// End of File