// Copyright (c) 2008-2009 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:

//

#ifndef __SSMSTATETRANSITIONENGINE_H__

#define __SSMSTATETRANSITIONENGINE_H__

#include <e32base.h>

#include <ssm/ssmstatetransition.h>

#include <ssm/ssmstatepolicy.h>

#include <ssm/ssmcmd.hrh>

class CSsmStatePolicyFrame;

class CSsmCommandList;	

class MCleSessionProxy;

class MSsmStatePolicyResolverProxy;

class CSsmStateTransitionRequest;

/** 

The CSsmStateTransitionEngine class is responsible for drivingin 

System State Changes by requesting answers and actions from System State 

Policy implememtations and the Command List Execution Server.

@internalComponent

@released

*/		

class CSsmStateTransitionEngine : public CActive

	{

public:

	static CSsmStateTransitionEngine* NewL(MSsmStatePolicyResolverProxy* aResolver, MCleSessionProxy* aCleSession);

	static CSsmStateTransitionEngine* NewLC(MSsmStatePolicyResolverProxy* aResolver, MCleSessionProxy* aCleSession);

	~CSsmStateTransitionEngine();

	TSsmStateTransition const* CurrentTransition() const;

	TSsmStateTransition const* QueuedTransition() const;

	MSsmStatePolicy::TResponse TransitionAllowed(const TSsmStateTransition& aRequest, const RMessagePtr2& aMessage);

	void SubmitL(const TSsmStateTransition& aRequest);

	void SubmitL(const TSsmStateTransition& aRequest, const RMessage2& aMessage);

	void Cancel(CSession2*);

	void PerformCommandListValidation(TBool aSetting);

#ifdef _DEBUG

	void CleanupTransitionEngine();

#endif

protected:

	//from CActive

	void DoCancel();

	void RunL();

	TInt RunError(TInt aError);

private:

	CSsmStateTransitionEngine(MSsmStatePolicyResolverProxy* aResolver, MCleSessionProxy* aCleSession);

	void DoSubmit(CSsmStateTransitionRequest* aRequest);

	void Start();

	void ShiftQueueIfNeeded();

	CSsmStatePolicyFrame* Policy();

	void DoConnectCleSessionL();

	void DoStartTransitionL();

	void DoInitialize();

	void DoPrepareCommandList();

	void DoExecuteCommandList();

	void DoValidation();

	TBool FurtherTransition();

	TBool InTransition() const;

private:

	enum TInternalActions

		{

		EUnConnected,

		EIdle,

		EStartTransition,

		EInitialize,

		EPrepareCommandList,

		EExecuteCommandList,

		EReadNextTransition

		};

	MSsmStatePolicyResolverProxy& iResolver;

	MCleSessionProxy& iCleSession;

	TBool iPerformCommandListValidation;

	CSsmStateTransitionRequest* iQueuedTransition;

	CSsmStateTransitionRequest* iCurrentTransition;

 	TSsmState iTargetSystemState;		 	

	TInternalActions iNextAction;

	/** The severity of the current command*/

	TCmdErrorSeverity iSeverity;

	CSsmCommandList* iCommandList;

	};

#endif