/*

* Copyright (c) 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: Declaration of CSsmStatePolicyBase class.

*

*/

#ifndef C_SSMSTATEPOLICYBASE_H

#define C_SSMSTATEPOLICYBASE_H

#include <ssm/ssmstatepolicy.h>

#include "ssmpolicybase.h"

/**

*  Base class for SSM state policy plugins

*

*/

class CSsmStatePolicyBase : public CSsmPolicyBase, public MSsmStatePolicy

    {

public:

    /**

    * First phase constructor.

    */

    IMPORT_C CSsmStatePolicyBase();

    /**

    * Destructor.

    */

    IMPORT_C virtual ~CSsmStatePolicyBase();

protected: // From MSsmStatePolicy

	/**

    * This function is guaranteed to be called before this System State Policy

    * is used. It is intended for e.g. opening resource files or if you need to

    * initialize hardware or talk to a domestic OS.

	*/

    IMPORT_C virtual void Initialize( TRequestStatus& aStatus );

	/**

    * Used to inform the policy DLL to Cancel an asynchronous Initialize

    * operation. Typically used to inform a MCommandListProvider that any open

    * resource files should be closed.

	*/

    IMPORT_C virtual void InitializeCancel();

	/**

    * Used to determine if an incoming request should be accepted or rejected.

	*

	* @param aRequest Contains information about the new request

	* @param aCurrent Contains NULL or the first accepted but not yet completed transition request

	* @param aQueued Contains NULL or a second accepted but not yet started transition request

    * @param aMessage Message sent by SSM server, used to check if the client has 'ECapabilityPowerMgmt'

	* @return The decision

	*/

    IMPORT_C virtual TResponse TransitionAllowed(

        const TSsmStateTransition& aRequest,

        TSsmStateTransition const* aCurrent,

        TSsmStateTransition const* aQueued,

        const RMessagePtr2& aMessage );

	/**

    * Used to create the command list associated with a minor state transition.

	*

    * @param aState	Contains the state that identifies the command list to create

	* @param aReason Contains the reason as given by the request

	* @param aStatus to complete when the operation has finished

	*/

    IMPORT_C virtual void PrepareCommandList(

        TSsmState aState,

        TInt aReason,

        TRequestStatus& aStatus );

	/**

    * Used to inform the policy DLL that the pending asynchronous

    * PrepareCommandList operation needs to be cancelled.

	*/

    IMPORT_C virtual void PrepareCommandListCancel();

	/**

    * Used to retrieve the command list once the  PrepareCommandList has

    * completed. Ownership of the returned command list is transferred to the

    * caller.

    *

    * @return The command list created during the preceding PrepareCommandList step

	*/

    IMPORT_C virtual CSsmCommandList* CommandList();

	/**

    * It is expected that Release will usually just call "delete this" on the

    * object, but this will depend on the implementation of each policy.

	*/

    IMPORT_C virtual void Release();

protected:

	/**

    * Used to determine if an incoming request to change state should be accepted or rejected.

	*/

    virtual TBool IsAllowedTargetState( const TSsmStateTransition& aRequest ) const = 0;

	/**

    * On return contains target substate - modified or requested.

	*/

    virtual TUint16 TargetSubState( const TUint16 aRequestedSubState ) = 0;

    };

#endif // C_SSMSTATEPOLICYBASE_H