/** @file

* Copyright (c) 2005-2006 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:  CUpnpHttpFileTransferWriter is a class responsible for 

*                   asynchronous writing to a socket owned by CUpnpTcpSession.

*

*/

#ifndef C_UPNPHTTPFILETRANSFERWRITER_H

#define C_UPNPHTTPFILETRANSFERWRITER_H

#include <e32base.h>

#include <in_sock.h>

#include "upnpretrywrite.h"

class CUpnpTcpSession;

class CUpnpHttpFileAccess;

/**

 *  CUpnpHttpFileTransferWriter is responsible for asynchronous writing.

 *  Writer class is owned by CUpnpTcpSession which request asynchronous 

 *  writing from it and is notified by writer when the write request 

 *  is completed or an error occured.

 *  When writer receives data to send it checks if it can be sent to the socket

 *  right away and if session is not yet connected or writer already sends data

 *  then it queues incoming data. When writing to the socket ends, writer checks 

 *  if there is data in queue waiting for sending. If thereis then it issues writing it 

 *  until the queue is empty. After writing all data, the writer notifies session about

 *  completion of the writing taska and switches to waiting state until it receives 

 *  another write request.

 *  @lib DLNAWebServer.lib

 *  @since Series60 3.2

 */

NONSHARABLE_CLASS (CUpnpHttpFileTransferWriter) : public CActive, MUpnpRetryWriteObserver

    {

public:

    /**

    * CUpnpHttpFileTransferWriter factory method.

    * @since Series60 3.2

    * @param aSession session that runs and supervises reader.

    * @param aSocket socket from which data will be read.

    * @param aPriority priority with which the reader will be working.

    */

    static CUpnpHttpFileTransferWriter* NewL( CUpnpTcpSession& aSession,

                                        RSocket& aSocket,

                                        TThreadPriority aPriority,

                                        TInt aWriteSize);

    /**

    * Virtual destructor.

    * @since Series60 3.2

    */   

    virtual ~CUpnpHttpFileTransferWriter();

public: // New functions

    /**

    * Passes control to the reader

    * @since series60 3.2    

    */  

    void StartL();

    /**

    * Resets state of the writer

    * @since series60 3.2   

    */

    void Reset();

    /**

    * Indicates it writer is waiting for connection

    * @since series60 3.2   

    */

    TBool IsWaiting();

    /**

    * Indicates it writer is in use

    * @since series60 3.2   

    */

    TBool IsActivated();

    /**

    * Indicates it iRetryWrite object is waiting to rewrite

    * @since series60 3.2   

    */

    TBool IsRetrying();

    /**

    * Indicates it file download is cancelled

    * @since series60 3.2   

    */

    TBool IsCancelled();

    /**

    * Sets that post notification is need

    * @since series60 3.2   

    */

    void SetPostNotify();

private: // from MUpnpRetryWriteObserver

    /**

    * Called when retrying of writing was succesed.

    * @since Series60 3.2

    */

	void RetryWriteSucceed();

    /**

    * Called when retrying of writing fail.

    * @since Series60 3.2

    */

	void RetryWriteFailL( TInt aError );

protected: // Functions from base CActive

    /**

    * Cancels issued writing request.

    * Standard active object function

    * @since Series60 3.2

    */

    void DoCancel();

    /**

    * Function called when the write request is finished.

    * Standard active object function

    * @since Series60 3.2

    */

    void RunL();

    /**

    * Trap RunL leaves

    * Standard active object function

    * @since Series60 3.2

    */

    TInt RunError( TInt aError );

private: // Constructors and destructors

    /**

    * CUpnpHttpFileTransferWriter constructor.

    * @since Series60 3.2

    * @param aSession session that runs and supervises reader.

    * @param aSocket socket from which data will be read.

    * @param aPriority priority with which the reader will be working.

    * @param aWriteSize

    */

    CUpnpHttpFileTransferWriter( CUpnpTcpSession& aSession,

                           RSocket& aSocket,

                           TThreadPriority aPriority,

                           TInt aWriteSize);

    /**

    * By default Symbian 2nd phase constructor is private.    

    * @since Series60 3.2

    */

    void ConstructL();

    /**

    * Sends next queued write request if such exists.

    * @since Series60 3.2

    */

    void SendNextPortionL();

    /**

    * Sends HTTP headers

    * @since Series60 3.2

    */

    void SendHeadersL();

    /**

    * Writes to the socket

    * @since Series60 3.2

    */

    void WriteToSocket();

    /**

    * Finishes downloading

    * @since Series60 3.2

    */

    void FinishL();

    /**

    * Handles RunL error

    * @since Series60 3.2

    */

    void HandleErrorL();

private: // Enumerations

    /**

    * TWriteState, records whether a write request is pending.

    *   - EUnknown Initial state

    *   - EHeaders Sending headers

    *   - EContent Sending content    

    *   - ECancelled Writing to the socket is cancelled

    */

   enum TFileTransferWriterState

    {

    EUnknown,

    EHeaders,

    EContent,

    EFinished,

    ECancelled

    };        

private: // Data

    /**

    * Socket used for writing data, not owned.

    */

    RSocket& iSocket;

    /**

    * Reference to session that owns the writer.

    * Session is request writing and is notified when it's finished or

    * errors occure, not owned.

    */

    CUpnpTcpSession& iSession;

    /**

    * State of the writer.

    */

    TFileTransferWriterState iState;

    /**

    * Buffer that is used to send data.    

    */

    RBuf8 iSendBuffer;

    /**

    * Pointer to data to be sent    

    */

    TPtr8 iSendPointer;

    /**

    * Size of the write buffer

    */

    TInt iWriteSize;

    /**

    * Indicates when writed needs to wait for connecting to the remote host

    */

    TBool iWaiting;

    /**

    * Indicates when POST is being sent

    */

    TBool iHttpPostStarted;    

    /**

    * Implementation of retrying write to the socket

    */

    CUpnpRetryWrite* iRetryWrite;

    };

#endif // C_UPNPHTTPFILETRANSFERWRITER_H

// End Of File