/*

* Copyright (c) 2005 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "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:  A task to update a Feed.

*

*/

#ifndef UPDATE_FEED_TASK_H

#define UPDATE_FEED_TASK_H

// INCLUDES

#include <e32base.h>

#include "FeedParserObserver.h"

#include "LoadObserver.h"

#include "Task.h"

// CONSTANTS

// MACROS

// DATA TYPES

// FUNCTION PROTOTYPES

// FORWARD DECLARATIONS

class CIdle;

class CFeedHandler;

class CHttpConnection;

class CPackedFeed;

class CUrlHandler;

// CLASS DECLARATION

/**

*  The UpdateFeedTask's observer.

*

*  \b Library: FeedsEngine.lib

*

*  @since 3.0

*/

class MUpdateFeedTaskObserver

    {

    public: 

        /**

        * Notifies the observer that the task is about to start a lengthy 

        * operation.  In response the observer could display somekind of 

        * status indicator.

        *

        * @since 3.0

        * @return void.

        */

        virtual void StartWait() = 0;

        /**

        * Called upon completion of the task.

        *

        * @since 3.0

        * @param aPackedFeed The resulting feed.  aPackedFeed is adopted by the 

        *                    implementing class.

        * @param aFeedUrl The feed's url.

        * @param aStatusCode The completion status of the request.

        * @return Void

        */

        virtual void Completed(CPackedFeed* aPackedFeed, const TDesC& aFeedUrl,TInt aFeedId, TInt aStatusCode) = 0;

        /**

        * Called upon start of the task.

        *

        * @since 3.1

        * @param .

        * @return connection

        */

        virtual CHttpConnection& HttpConnection() = 0;

    };

/**

*  A task to update a Feed.

*

*  \b Library: FeedsEngine.lib

*

*  @since 3.0

*/

class CUpdateFeedTask: public CTask, public MLoadObserver, public MFeedParserObserver

    {

    public:  // Constructors and destructor

        /**

        * Two-phased constructor.

        */

        static CUpdateFeedTask* NewL(CFeedsServer& aFeedsServer, 

                const TDesC& aUrl,TInt aFeedId, MUpdateFeedTaskObserver& aObserver);

        /**

        * Two-phased constructor.

        */

        static CUpdateFeedTask* NewL(CFeedsServer& aFeedsServer, const TDesC& aUrl,TInt aFeedId, 

                TDesC8* aFeedBuffer, MUpdateFeedTaskObserver& aObserver);

        /**

        * Destructor.

        */        

        virtual ~CUpdateFeedTask();

    public:  // From CTask

        /**

        * Starts the task.

        *

        * @since 3.0

        * @return Void

        */

        virtual void StartTaskL();

    public:  // From MLoadObserver

        /**

        * Notifies the observer that the UrlHandler is about to start a lengthy 

        * operation.  In response the observer could display somekind of 

        * status indicator.

        *

        * @since 3.0

        * @return void.

        */

        virtual void StartWait();

        /**

        * Passes the status code and responseBody to the observer.  The observer

        * adopts aResponseBody.

        *

        * @since 3.0

        * @param aStatusCode The status code - normalized to the http response codes.

        * @param aResponseBody The response body or NULL.

        * @param aContentType The content-type.

        * @param aCharSet The char-encoding.

        * @return void.

        */

        virtual void LoadCompleted(TInt aStatusCode, TDesC8* aResponseBody,

                const TDesC& aContentType, const TDesC& aCharSet);

    public:  // From MFeedParserObserver

        /**

        * The beginning of a feed was found.

        *

        * @since 3.1

        * @return void.

        */

        virtual void FeedBeginsL();

        /**

        * The end of a feed was found.

        *

        * @since 3.1

        * @return void.

        */

        virtual void FeedEndsL();

        /**

        * The beginning of a item was found.

        *

        * @since 3.1

        * @return void.

        */

        virtual void ItemBeginsL();

        /**

        * The end of a item was found.

        *

        * @since 3.1

        * @return void.

        */

        virtual void ItemEndsL();

        /**

        * The beginning of a enclosure was found.

        *

        * @since 3.1

        * @return void.

        */

        virtual void EnclosureBeginsL();

        /**

        * The end of a enclosure was found.

        *

        * @since 3.1

        * @return void.

        */

        virtual void EnclosureEndsL();

        /**

        * A attribute was found.  This attribute should be applied to

        * the enclosing entity (Feed, Item, or Enclosure).

        *

        * @since 3.1

        * @param aAttribute The attribute.

        * @param aValue The attribute's value.

        * @return void.

        */

        virtual void AddAttributeL(TInt aAttribute, const TDesC& aValue);

        /**

        * An unimportant element was found.  The client can use this 

        * information for feed validation.

        *

        * @since 3.1

        * @return void.

        */

        virtual void OtherTitleL();

        /**

        * An unimportant element was found.  The client can use this 

        * information for feed validation.

        *

        * @since 3.1

        * @return void.

        */

        virtual void OtherDescriptionL();

        /**

        * An unimportant element was found.  The client can use this 

        * information for feed validation.

        *

        * @since 3.1

        * @return void.

        */

        virtual void OtherLinkL();

    private:

        /**

        * C++ default constructor.

        */

        CUpdateFeedTask(CFeedsServer& aFeedsServer, MUpdateFeedTaskObserver& aObserver);

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL(const TDesC& aUrl,TInt aFeedId);

        /**

        * Parses the buffer to the observer now that the callstack has unrolled.

        *

        * @since 3.0

        * @param aPtr The this pointer.

        * @return Always returns EFalse.

        */

        static TInt DelayedParse(TAny* aPtr);

    private:

        TLeakTracker              iLeakTracker;

        MUpdateFeedTaskObserver&  iObserver;

        CIdle*                    iIdle;

        CUrlHandler*              iUrlHandler;

        TDesC*                    iUrl;

        TDesC8*                   iFileBuffer;

        CPackedFeed*              iPackedFeed;

        TInt 					  iFeedId;

    };

#endif      // UPDATE_FEED_TASK_H

// End of File