/*

* Copyright (c) 2006-2009 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:

* Name          : UserAgentServer.h

* Part of       : TransactionUser

* Version       : SIP/5.0

*

*/

/**

 @internalComponent

*/

#ifndef USERAGENTSERVER_H

#define USERAGENTSERVER_H

// INCLUDES

#include <stringpool.h>

#include "MSIPRequestRouterObserver.h"

#include "CUserAgent.h"

// FORWARD DECLARATIONS

class MSIPRequestRouter;

class MSipDialogs;

class CTimerOwnerResolver;

// CLASS DECLARATION

class CUserAgentServer :

	public CUserAgent,

	public MSIPRequestRouterObserver

	{

public: // Destructor

	virtual ~CUserAgentServer();

public: // From CUserAgent

	TBool IsUAS() const;

protected: // From CUserAgent

	virtual void CreateTransactionL() = 0;

private: // From CUserAgent

	TRegistrationId RegistrationId() const;

public: // From MSIPRequestRouterObserver

	void OwnerFoundL(TUint32 aRequestId, MTransactionOwner* aOwner);

	void OwnerNotFoundL(TUint32 aRequestId, CSIPResponse* aResp);

	void ErrorOccurred(TUint32 aRequestId, TInt aError);

public: // New functions

	/**

	 * The initial request has been received by the UAS.

	 *

	 * @pre aReq != NULL

	 *

	 * @param aReq SIP request received from network. Ownership is transferred.

	 * @param aGetTxOwner State the UAS enters if it tries to obtain

	 * 	MTranactionOwner.

	 * @param aWaitRespFromApp State the UAS enters if the request belongs to

	 *	an existing dialog.

	 * @param aErrorRespSent State the UAS enters when either Dialog subsystem

	 *	or UAS itself decides to send a final response without passing the

	 *	request.	 

	 */

	void InitialRequestReceivedL(CSIPRequest* aReq,

								 const CUserAgentState& aGetTxOwner,

								 const CUserAgentState& aWaitRespFromApp,

								 const CUserAgentState& aErrorRespSent);

	/**

	 * Callback to upper layer has been obtained. UAS passes the request there

	 * and starts waiting for a response.

	 *

	 * @pre aOwner != NULL

	 *

	 * @param aOwner Callback to upper layer, ownership isn't transferred

	 * @param aWaitRespFromApp State which UAS enters next.	 

	 */

	void HandleOwnerFoundL(MTransactionOwner* aOwner,

						   const CUserAgentState& aWaitRespFromApp);

	/**

	 * Application to receive the request was not found. Instead a SIP response

	 * will be sent to network.

	 *

	 * @pre aResp != NULL

	 *

	 * @param aResp Final response. May not be 2xx in case of INVITE.

	 *	Ownership is transferred.

	 * @param aErrorRespSent State which UAS enters next.	 

	 */

	void HandleOwnerNotFoundL(CSIPResponse* aResp,

							  const CUserAgentState& aFinalRespSent);

    /**

	 * Error occurred during the routing of an incoming SIP request.

	 */

    void RequestRouterErrorL();

    /**

	 * Sends error response to remote endpoint.

	 *

     * @param aErrorRespSent UserAgent enters this state	 

	 */

    void HandleRequestRouterErrorL(const CUserAgentState& aErrorRespSent);

	/**

	 * Upper layer sends response. UAS checks that response is correct and

	 * fills the transaction related headers.

	 *

	 * @pre aResp != NULL

	 *

	 * @param aResp SIP response, ownership isn't transferred

	 * @param aParam Transport parameters to use when sending the response	 

	 */

	void HandleSendResponseL(CSIPResponse* aResp,

							 const TSIPTransportParams& aParams);

	/**

	 * Checks that the SIP response message given by upper layer has the

	 * required parts filled. If the response isn't ok, function leaves.

	 *

	 * @param aResp SIP response	 

	 */

	void CheckResponseL(const CSIPResponse& aResp) const;

	/**

	 * Fills the transaction related parts into the SIP response.	 

	 *

	 * @param aResp IN/OUT: Partially filled SIP response from upper layer.	 

	 */

	void FillResponseL(CSIPResponse& aResp);

	/**

	 * Contacts Dialogs subsystem to find out if there is a dialog for the

	 * received request

	 *

	 * @pre iObserver = NULL, iOutgoingMsg = NULL

	 *

	 * @param aReq Request received from network

	 * @return value ETrue: Dialog exists, EFalse: otherwise

	 */

	TBool DoesDialogExistForRequestL(CSIPRequest& aReq);

	/**

	 * Pass the SIP response to transaction for sending.

	 *

	 * @pre iTransaction != NULL, aResp != NULL

	 *

	 * @param aResp SIP response to send, ownership is transferred.	 

	 */

	void SendResponseToTransactionL(CSIPResponse* aResp) const;

	/**

	 * Checks the request received from network is correct.

	 *

	 * @pre aReasonPhrase != NULL	 

	 *

	 * @param aReq SIP request received from network

	 * @param aResponseCode If function returns EFalse, this parameter will

	 *  contain the response code of the response that should be sent back to

     *  the sender of the invalid request.

	 * @param aReasonPhrase If function returns EFalse, this parameter will

	 *  have the reason phrase that should be sent back to the sender of the

	 *  invalid request.

	 * @return value ETrue if the request is ok, EFalse otherwise.	 

	 */

	TBool CheckReceivedRequest(CSIPRequest& aReq,

							   TInt& aResponseCode,

							   RStringF& aReasonPhrase) const;

	/**

	 * Obtains the To tag

	 *	 	 

	 * @return value To tag

	 */

	RStringF ToTag() const;

protected:

	CUserAgentServer(CUserAgentCreateParams& aParams,

					 MSipDialogs& aDialogs,

					 MSIPRequestRouter& aRouter);	

	/**

	 * Creates and sends a final response

	 *

	 * @pre aResponseCode >= 300

	 *	 

	 * @param aResponseCode Response code to be put into the response

	 * @param aReasonPhrase Reason phrase to be put in the response

	 * @param aErrorRespSent State which UAS enters after sending the response	 

	 */

	void SendErrorResponseL(TInt aResponseCode,

						    RStringF aReasonPhrase,

						    const CUserAgentState& aErrorRespSent);

    /**

	 * Cancels the asynchronous request to obtain MTransactionOwner callback.

	 */

	void CancelGetOwnerRequest() const;

    void StopTimerOwnerResolver();

    /**

	 * Store the tag of To-header, if it exists.

	 *

	 * @pre iToTag.DesC().Length() == 0

	 *	 

	 * @param aMsg SIP message

	 */

    void StoreToTag(CSIPMessage& aMsg);

protected: // Data

    //Dialog subsystem

	MSipDialogs& iDialogs;

    //Timer specifying how long UAS waits for RequestRouter to provide the

    //MTransactionOwner of upper layer or an error response. Owned.

    CTimerOwnerResolver* iTimerOwnerResolver;

private:

	/**

	 * The received request doesn't belong to any dialog

	 *

	 * @pre aReq != NULL

	 *

	 * @param aReq SIP request. Ownership is transferred.

	 * @param aGetTxOwner State which UAS enters if it contacts AssocMgr for

	 *	obtaining MTranactionOwner.

	 * @param aErrorRespSent State which UAS enters when either Dialog

	 * subsystem or UAS itself decides to send a final response without passing

	 *	the request.

	 */

	void RequestOutsideDialogL(CSIPRequest* aReq,

							   const CUserAgentState& aGetTxOwner,

							   const CUserAgentState& aErrorRespSent);

	/**

	 * Fill and send the SIP response got from Dialogs subsystem. The

	 * response is located in the send buffer (iOutgoingMsg).

	 * Ownership of the response is passed to transaction.

	 *

	 * @pre iOutgoingMsg != NULL

	 * @pre SIP response in iOutgoingMsg must be a 3xx-6xx

	 * @post iOutgoingMsg == NULL

	 *

	 * @param aNextState State where UserAgent moves after sending the response	 

	 */

	void HandleResponseFromDialogsL(const CUserAgentState& aNextState);

    /**

	 * Send the stored SIP request located in the receive buffer

     * (iIncomingMsg) to MTransactionOwner.

	 *

	 * @pre iIncomingMsg != NULL

	 * @post iIncomingMsg == NULL	 

	 */

	void PassStoredRequestToTransactionOwnerL();    

    /**

	 * Start timer determining how long UAS waits for OwnerResolver to

	 * return a callback to upper layer.

     * Timer duration must be shorter than timer F2.

	 *

	 * @pre iTimerOwnerResolver = NULL

	 */

    void StartTimerOwnerResolverL();

private: // Data

	//Router which decides where the incoming SIP request will be forwarded.

	MSIPRequestRouter& iRouter;

	//RequestId received from iRouter

	TUint32 iRouterRequestId;

	//Tag to be inserted into the To-header of SIP responses

	RStringF iToTag;

private: // For testing purposes

#ifdef CPPUNIT_TEST	

	friend class CNormalUAS_GetTxOwner_Test;

	friend class CUserAgentServer_Test;

	friend class CTransactionUser_Test;

#endif

	void __DbgTestInvariant() const;

	};

#endif // end of USERAGENTSERVER_H

// End of File