/*

* Copyright (c) 2006 - 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:    Connection handler is responsible for creating connections

*                to Connection Multiplexer and TURN Client. It is responsible

*                to handle data received from different observers it

*                implements. Connection handler implements 3 Connection

*                Multiplexer's observers and STUNClientObserver.

*

*/

#ifndef C_NATFWTURNCONNECTIONHANDLER_H

#define C_NATFWTURNCONNECTIONHANDLER_H

#include <e32base.h>

#include <e32std.h>

#include <es_sock.h>

#include <in_sock.h>

#include "mncmconnectionobserver.h"

#include "mncmincomingconnectionobserver.h"

#include "mncmoutgoingconnectionobserver.h"

#include "mncmmessageobserver.h"

#include "natfwstunclientobserver.h"

#include "natfwrefreshobserver.h"

#include "natfwtimerobserver.h"

// forward declarations

class MNATFWPluginObserver;

class MNcmConnectionMultiplexer;

class CNATFWCandidate;

class CNATFWTurnRefreshTimer;

class CSTUNRelayBinding;

class CSTUNClient;

class TStreamData;

class TConnectionData;

class CNATFWNatSettingsApi;

class MNATFWTurnSettings;

class CNATFWTurnActiveDestinationTimer;

class CTurnAsyncCallback;

class CNATFWPluginApi;

class MNATFWServerSettings;

class CTurnServerSettings;

/**

 *  Connection handler for TURN Plug-in.

 *

 *  Connection handler is responsible for creating connections to Connection

 *  Multiplexer and TURN Client. It creates TURN Binding and it is responsible

 *  to handle data received from different observers it implements. Connection

 *  handler implements 3 Connection Multiplexer's observers and

 *  STUNClientObserver.

 *

 *  @lib turnplugin.lib

 *  @since S60 v3.2

 */

class CNATFWTurnConnectionHandler : public CBase,

                                    public MSTUNClientObserver,

                                    public MNcmConnectionObserver,

                                    public MNcmIncomingConnectionObserver,

                                    public MNcmOutgoingConnectionObserver,

                                    public MNcmMessageObserver,

                                    public MNATFWRefreshObserver,

                                    public MNATFWTimerObserver

    {

    friend class UT_CNATFWTurnConnectionHandler;

public:

    /**

     * Two-phased constructor.

     * @param aTurnPlugin The TURN plugin instance

     * @param aPluginObserver Observer for callbacks to STUN plug-in's client

     */

    static CNATFWTurnConnectionHandler* NewL(

        const CNATFWPluginApi& aTurnPlugin,

        MNATFWPluginObserver& aPluginObserver );

    /**

     * Two-phased constructor.

     * @param aTurnPlugin The TURN plugin instance

     * @param aPluginObserver Observer for callbacks to STUN plug-in's client

     */

    static CNATFWTurnConnectionHandler* NewLC(

        const CNATFWPluginApi& aTurnPlugin,

        MNATFWPluginObserver& aPluginObserver );

    ~CNATFWTurnConnectionHandler();

    /**

     * Initializes TURN Connection Handler.

     *

     * @since S60 v3.2

     * @param aIapId        IAP ID used in retrieving IAP settings from

     *                      NAT FW NAT Settings

     * @param aDomain       Domain name used in creating instance of NATFW

     *                      NAT Settings to get STUN server address and port.

     * @param aMultiplexer  Reference to the Connection Multiplexer

     */

    void PluginInitializeL( TUint32 aIapId,

                            const TDesC8& aDomain,

                            MNcmConnectionMultiplexer& aMultiplexer );

    /**

     * Finds out a STUN Server and establishes a connection to it.

     * 

     * MNATFWPluginObserver::Notify is called with event code EServerConnected

     * when connecting has completed.

     *

     * FetchCandidateL can be called after successful connecting.

     *

     * This is done asynchronously.

     * 

     * @since   S60 v3.2

     * @param   aSocketServ         The handle to socket server session

     * @param   aConnectionName     The unique name of the RConnection

     */

    void ConnectServerL( const RSocketServ& aSocketServ,

        const TName& aConnectionName );

    /**

     * Fetches available candidates for a specified stream using given

     * retransmission timeout for STUN transactions.

     * 

     * RTO value 0 indicates default retransmission timeout as specified

     * in STUN specification.

     * 

     * @since   S60 v3.2

     * @param   aStreamId       Stream identifier

     * @param   aRtoValue       Retransmission timeout in milliseconds

     * @param   aAddrFamily     KAFUnspec / KAfInet / KAfInet6

     * @param   aBaseAddr       Address from which to create connection

     */

    void FetchCandidateL( TUint aStreamId, TUint aRtoValue, TUint aAddrFamily,

        const TInetAddr& aBaseAddr );

    /**

     * Gets identifier for a connection that is associated with the

     * given local end point.

     * 

     * @since   S60 v3.2

     * @param   aLocalCandidate     The local end point for a media

     * @param   aStreamId           The stream identifier

     * @param   aConnectionId       Reference to found ID

     */

    void GetConnectionIdL( const CNATFWCandidate& aLocalCandidate,

        TUint aStreamId, TUint& aConnectionId );

    /**

     * Starts TURN Refresh timer. Sends periodically keepalive messages to

     * TURN client, which will keep the bindings to TURN Server active.

     *

     * @since   S60 v3.2

     */

    void StartTurnRefresh();

    /**

     * Creates TURN Binding and calls AllocateRequestL().

     *

     * @since S60 v3.2

     * @param aStreamId      Stream ID of current TURN Binding

     * @param aConnectionId  Connection ID of current TURN Binding

     */

    void CreateTURNBindingL( TUint aStreamId, TUint aConnectionId );

    /**

     * Enables/disables media receiving for the specified local candidate.

     * 

     * MNATFWPluginObserver::Notify is called with event code

     * EReceivingActivated/EReceivingDeactivated when status change has 

     * completed. While activated incoming data is delivered to the media

     * engine.

     * 

     * @since   S60 v3.2

     * @pre     FetchCandidate(/s) and possible ICE processing have completed

     * @param   aLocalCandidate The local end point for a media

     * @param   aState          The receiving state

     */

    void SetReceivingStateL( const CNATFWCandidate& aLocalCandidate,

        TNATFWStreamingState aState );

    /**

     * Once the client wants to primarily receive from one peer, it can send

     * a SetActiveDestination request.  All subsequent data received from

     * the active peer is forwarded directly to the client and vice versa,

     * except that it is wrapped or framed according to the protocol used

     * between the STUN relay client and STUN relay server.

     * The SetActiveDestination Request does not close other bindings. Data

     * to and from other peers is still wrapped in Send and Data indications

     * respectively.

     *

     * @since   S60 v3.2

     * @param   aLocalCandidate The local end point for a media

     * @param   aState          The sending state

     * @param   aDestAddr       The remote end point for a media

     */

    void SetSendingStateL( const CNATFWCandidate& aLocalCandidate,

        TNATFWStreamingState aState, const TInetAddr& aDestAddr );

    /**

     * Validates that is outgoing message a TURN request or Send Indication.

     *

     * @since   S60 v3.2

     * @param   aMessage    Message from which will be validated if

     *                      it is TURN request or Send Indication

     * @return ETrue if the message is TURN request or Send Indication

     */

    TBool IsRequestOrIndicationL( const TDesC8& aMessage ) const;

    /**

     * Validates that is incoming message a TURN response.

     *

     * @since   S60 v3.2

     * @param   aMessage    Message from which will be validated if

     *                      it is TURN response

     * @return ETrue if the message is TURN response

     */

    TBool IsTurnResponseL( const TDesC8& aMessage ) const;

// From base class MStunClientObserver

    /**

     * Indicates that asynchronous initialization of the related

     * CSTUNClient has been completed and it can be used for 

     * creating CSTUNRelayBinding(s).

     *

     * @since S60 v3.2

     * @param aClient         Handle to STUN client

     * @param aCompletionCode Completion code

     */

    void STUNClientInitCompleted( const CSTUNClient& aClient,

                                  TInt aCompletionCode );

    /**

     * A TURN binding related event occurred. After this callback

     * the aBinding can be used again by calling its SendRequestL

     * function.

     *

     * @since S60 v3.2

     * @param aEvent   Binding event occurred

     * @param aBinding Handle to CBinding

     */

    void STUNBindingEventOccurredL( TSTUNBindingEvent aEvent,

                                    const CBinding& aBinding );

    /**

     * Error occurred during IP address resolution. This callback

     * will also be called if STUNBindingEventOccurredL leaves.

     *

     * @since S60 v3.2

     * @param aBinding Handle to CBinding

     * @param aError   Error code

     */

    void STUNBindingErrorOccurred( const CBinding& aBinding,TInt aError );

 // from base class MNcmConnectionObserver

    /**

     * Called by Connection Multiplexer when connection connecting completes.

     *

     * @since S60 v3.2

     * @param aStreamId     Stream of target of notify

     * @param aConnectionId Target of notify

     * @param aType         Type of notify

     * @param aError        Error code

     */

    void ConnectionNotify( TUint aStreamId,

                           TUint aConnectionId,

                           TConnectionNotifyType aType,

                           TInt aError );

// from base class MNcmIncomingConnectionObserver

    /**

     * Called by Connection Multiplexer when incoming message is found.

     *

     * @since   S60 v3.2

     * @param   aStreamId           The ID identifying stream

     * @param   aMessage            Message is a reference to constant message

     * @param   aConsumed           Flag to indicate is this message consumed

     * @param   aLocalAddr          A stream local address.

     * @param   aFromAddr           A remote source address. ( From socket )

     * @param   aPeerRemoteAddr     A peer remote address.

     * @param   aConsumed           A reference to a boolean variable which MUST

     *                              be set by observer: ETrue is message was 

     *                              consumed, EFalse otherwise.

     */

    void IncomingMessageL( TUint aStreamId, const TDesC8& aMessage,

        const TInetAddr& aLocalAddr, const TInetAddr& aFromAddr,

        const TInetAddr& aPeerRemoteAddr, TBool& aConsumed );

// from base class MNcmOutgoingConnectionObserver

    /**

     * Called by Connection Multiplexer when outgoing message is found.

     *

     * @since S60 v3.2

     * @param aStreamId             Stream where message was found

     * @param aConnectionId         Connection where message was found

     * @param aDestinationAddress   Destination address where the packet

     *                              is being sent to. If this is set then

     *                              connection ID is ignored       

     * @param aMessage              Message is a reference to constant message

     *                              which was found

     * @param aConsumed             Is reference to a boolean variable which

     *                              MUST be set by observer: ETrue is message

     *                              was consumed, EFalse otherwise.

     */

    void OutgoingMessageL( TUint aStreamId, TUint aConnectionId,

        const TInetAddr& aDestinationAddress, const TDesC8& aMessage,

        TBool& aConsumed );

// from base class MNcmMessageObserver

    /**

     * Called by Connection Multiplexer when incoming message is found.

     * Allows connection observer to observe and make modifications to found

     * message by offering an own copy of content with modification(s).

     *

     * TURN Plug-in must fill the peer address, because only TURN Plug-in can

     * know currently activated destination.

     *

     * @since   S60 v3.2

     * @param   aStreamId           The ID identifying stream

     * @param   aMessage            Message is a reference to constant message

     * @param   aLocalAddr          A stream local address.

     * @param   aFromAddr           A remote source address. ( From socket )

     * @param   aPeerRemoteAddr     A peer remote address.

     * @return  Pointer to a heap descriptor with new content for message,

     *          otherwise NULL is returned. Ownership of the heap descriptor

     *          is transferred to connection multiplexer ( from observer ).

     */

    HBufC8* IncomingMessageNotify( TUint aStreamId,

                                   const TDesC8& aMessage,

                                   const TInetAddr& aLocalAddr,

                                   const TInetAddr& aFromAddr,

                                   TInetAddr& aPeerRemoteAddr );

// from base class MNcmMessageObserver

    /**

     * Called by Connection Multiplexer when outgoing message is found.

     * Allows connection observer to observe and make modifications to found

     * message by offering an own copy of content with modification(s).

     *

     * @since S60 v3.2

     * @param aStreamId             The ID identifying stream

     * @param aConnectionId         The ID identifying connection

     * @param aDestinationAddress   Destination address where the packet

     *                              is being sent to.   

     * @param aMessage              Message is a reference to constant message

     *                              which was found

     * @return pointer to a heap descriptor with new content for message,

     *         otherwise NULL is returned. Ownership of the heap descriptor is

     *         transferred to multiplexer (from observer).

     */

    HBufC8* OutgoingMessageNotify( TUint aStreamId,

                                   TUint aConnectionId,

                                   const TInetAddr& aDestinationAddress,

                                   const TDesC8& aMessage );

 // from base class MNATFWRefreshObserver

    /**

     * Sends binding requests to TURN Bindings.

     *

     * @since S60 v3.2

     */

    void BindingRefreshL();

// from base class MNATFWTimerObserver

    /**

     * Notifies when active destination timer has triggered.

     *

     * @since S60 v3.2

     * @param  aStreamId        To identify the binding that the

     *                          triggering was related to

     * @param  aConnectionId    To identify the binding that the

     *                          triggering was related to

     */

    void TimerTriggeredL( TUint aStreamId, TUint aConnectionId );

private:

    CNATFWTurnConnectionHandler( const CNATFWPluginApi& aTurnPlugin );

    void ConstructL( MNATFWPluginObserver& aPluginObserver );

    void DeleteStream( TUint aStreamInd, TBool aRemoveMuxConn );

    HBufC8* HandleIncomingMessageL( TUint aStreamId, const TDesC8& aMessage, 

        const TInetAddr& aLocalAddr, const TInetAddr& aFromAddr, 

        TInetAddr& aPeerRemoteAddr );

    TInt IndexByStreamId( TUint aStreamId );

    TConnectionData* ConnectionById( TUint aStreamInd, TUint aConnectionId );

    TConnectionData* ConnectionByIndex( TUint aStreamInd,

        TUint aConnectionInd );

    void GenerateServerListL();

    void TryNextServerL();

    TConnectionData* FindConnection( TUint aStreamId,

        const TInetAddr& aLocalAddr );

    TBool MatchAddresses( const TInetAddr& aAddr1, const TInetAddr& aAddr2 );

private:

    /**

     * Flag defining whether TURN refresh has been started

     */

    TBool iTurnRefreshStarted;

    /**

     * Currently selected index in list of servers ( iServerList )

     */    

    TInt iServerIndex;

    /**

     * Handle to the socket server.

     */

    RSocketServ iSocketServ;

    /**

     * Handle to the connection.

     * Own.

     */

    RConnection iConnection;

    /**

     * Pointer to domain name data.

     * Own.

     */

    HBufC8* iDomain;

    /**

     * Array for storing data for each stream

     */

    RArray<TStreamData> iStreamArray;

// Instances from other C -classes

    /**

     * STUN and TURN client handle.

     * Own.

     */

    CSTUNClient* iStunClient;

    /**

     * Set up stream for client.

     * Not own.

     */

    MNcmConnectionMultiplexer* iConnMux;

    /**

     * Sends keepalive messages periodically.

     * Own.

     */

    CNATFWTurnRefreshTimer* iTurnRefreshTimer;

    /**

     * Timer for setting Active Destination.

     * Own.

     */

    CNATFWTurnActiveDestinationTimer* iActiveDestinationTimer;

    /**

     * Pointer to timer for STUN Client.

     * Own.

     */

    CDeltaTimer* iTimerServ;

    /**

     * Pointer to NAT Settings.

     * Own.

     */

    CNATFWNatSettingsApi* iNatSettings;

    /**

     * Pointer to TURN related NAT Settings.

     * Not own.

     */

    MNATFWTurnSettings* iTurnSettings;

    /**

     * TURN UDP Refresh interval.

     */

    TUint iTurnRefreshInterval;

    /**

     * TURN Plug-in

     * Not own.

     */

    const CNATFWPluginApi& iTurnPlugin;

    /**

     * Async callback handler

     * own.

     */

    CTurnAsyncCallback* iAsyncCallback;

    /**

     * Array of server related settings

     * Own.

     */