/*

* Copyright (c) 2009 Aricent and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "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:

* Aricent - initial contribution.

*

* Contributors:

*

* Description:

* State machine for all video hwdevice plugins.

*

*/

#ifndef ARISTATEMACHINE_H

#define ARISTATEMACHINE_H

#include <e32base.h>

#include "ariprint.h"

// Constants

const TUint KNumOfStates    = 13;

const TUint	KNumOfCommands	= 8;

class CStateMachine : public CBase

{

public:

	/**

     * All the states of the state machine.

	 */

	enum TState

		{

		EUnInitialized = 0,

		EInitializing,

		EInitialized,

		EStart,

		EPause,

		EStop,

		EInitializedInStopping,

		EStopping,

		EPauseInStopping,

		EStopInInputEnd,

		EInitializedDeadState,

		ENonInitializedDeadState,

		EInvalidState

		};

	/**

     * Commands that are given to state machine

	 */

	enum TCommand

		{

		EInitializeCommand = 0 ,

		EInitializingCommand,

		EStartCommand,

		EPauseCommand,

		EResumeCommand,

		EInputEndCommand,

		EStopCommand,

		EDeadStateCommand

		};

public:

	/**

	 *Constructor. State will be in EUnInitialized

	 *

	 *@param	"None"

	 *@leave	"None"

	 *@return	"None"

	 */

	IMPORT_C static CStateMachine* NewL();

	/**

	 *Checks whether transition to new state is possible or not

	 *

	 *@param	"aCommand"	"Command for the transition"

	 *@leave	"None"

	 *@return	"Return ETrue if transition is valid, else EFalse

	 */

	IMPORT_C TBool	IsTransitionValid (TCommand aCommand);

	/**

	 *Transits to new state. If transition cann't be done, object will

	 *remain in the previous state.

	 *

	 *@param	"aCommand"	"Command for the transition"

	 *@return	"Return KErrNone if transition happens else error.

	 */

	IMPORT_C TInt	Transit (TCommand aCommand);

	/**

	 *Tells whether the state is initialized or not. Here initilized means

	 *if the state is in any state other than EUnInitialized

	 *

	 *@param	"None"

	 *@return	"Return ETrue, if state is initialized else EFalse.

	 */

	IMPORT_C TBool	IsInitialized ();

	/**

	 *Tells whether the state is exactly in EInitialized state or not.

	 *

	 *@param	"None"

	 *@return	Return ETrue, if in EInitialized state else EFalse.

	 */

    IMPORT_C TBool IsInInitializedState ();

	/**

	 *Tells whether the state is in initializing state or not.

	 *

	 *@param	"None"

	 *@return	"Return ETrue, if state is initializing else EFalse.

	 */

	IMPORT_C TBool	IsInitializing ();

	/**

	 *Tells whether the state is in any one of the input ending states i.e

	 *	EInitializedInStopping,

	 *	EStopping,

	 *	EPauseInStopping,

	 *	EStopInInputEnd

	 *

	 *

	 *@param	None

	 *@return	Return ETrue, if state is in any of inputend state else EFalse

	 */

	IMPORT_C TBool	IsInputEndPending ();

	/**

	 *Tells whether state is in EStart state

	 *

	 *@param	"None"

	 *@return	"Return ETrue if state is EStart, elase EFalse

	 */

	IMPORT_C TBool	IsStarted ();

	/**

	 *Tells whether state is in EPause state

	 *

	 *@param	"None"

	 *@return	"Return ETrue if state is EPause, elase EFalse

	 */

	IMPORT_C TBool	IsPaused ();

	/**

	 *Tells whether state is in EStop state

	 *

	 *@param	"None"

	 *@return	"Return ETrue if state is EStop, elase EFalse

	 */

	IMPORT_C TBool	IsStopped ();

	/**

	 *Tells whether state is in EPlaying state

	 *

	 *@param	"None"

	 *@return	"Return ETrue if state is EPlaying, elase EFalse

	 */

	IMPORT_C TBool	IsPlaying ();

	/**

	 *Tells whether state is in EInitializedDeadState/ENonInitializedDeadState

	 *state

	 *

	 *@param	"None"

	 *@return	"Return ETrue if state is

	 *           Return EInitializedDeadState/ENonInitializedDeadState,

	 *           elase EFalse"

	 */

	IMPORT_C TBool	IsInDeadState ();

	/**

	 *Resets the state machine to EUnInitialized state

	 *

	 *@param	"None"

	 *@return	"None"

	 */

	IMPORT_C void	Reset();

	/**

	 * Returns whether the current state is in initailize or not

	 *

	 *@return	"ETrue if current state is in Initailize"

	 */

	IMPORT_C TBool IfIsStateInInitailize();

	/**

	 * Destructor of the statemachine

	 *

	 *@return	"None"

	 */

	~CStateMachine();

private:

	/**

	 *Symbian 2nd phase constructor

	 *@return	"None"

	 */

	void ConstructL();

    /**

	 *Default Constructor

	 */

	CStateMachine();

private:

	//Stores the state of the state machine

	TState			iState;

	TState			iStateChanges[KNumOfStates][KNumOfCommands];

};

#endif // ARISTATEMACHINE_H