// Copyright (c) 1999-2009 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 __ASSRVITERATORBASE_H__

#define __ASSRVITERATORBASE_H__

// System includes

#include <e32base.h>

// User includes

#include "ASSrvAlarm.h"

// Classes referenced

class CASSrvAlarmQueue;

//

// ----> RASSrvIteratorBase (header)

//

/**

 * The base class for server iterators

 */

class RASSrvIteratorBase

	{

//

public:										// CONSTRUCT

//

	/**

	 * Constructor

	 */

	RASSrvIteratorBase(CASSrvAlarmQueue& aQueue);

	/**

	 * Only the primary iterator should ever be opened.

	 */

	void									Open();

//

public:										// ACCESS

//

	/**

	 * Is another alarm available?

	 */

	virtual TBool							NextAlarmAvailable() const;

	/**

	 * Return the next available alarm

	 */

	virtual TASSrvAlarm&					NextAlarm();

	/**

	 * Resets the iterator back to the start of the queue

	 */

	virtual void							Reset();

	/**

	 * Attaches another iterator to this one. Allows iterators to be chained

	 * together so that different conditions can be satisfied without complex

	 * (custom-written) individual iterator combinations.

	 */

	virtual void							IteratorAttach(RASSrvIteratorBase& aIterator);

	/**

	 * Release a previously attached iterator

	 */

	virtual void							IteratorRelease();

//

protected:									// INTERNAL

//

	/**

	 * Is an iterator attached?

	 */

	TBool									IteratorAttached() const;

	/**

	 * Access the attached iterator

	 */

	RASSrvIteratorBase&						Iterator();

	/**

	 * Access a constant handle to the attached iterator

	 */

	const RASSrvIteratorBase&				Iterator() const;

	/**

	 * Synchronise this iterator with another

	 */

	virtual void							IteratorSynchronize(RASSrvIteratorBase& aInterator);

	/**

	 * Does the specified alarm satisfy the criteria associated with

	 * this iterator?

	 */

	virtual TBool							Matches(const TASSrvAlarm& aAlarm) const;

//

private:									// INTERNAL

//

	/**

	 * Return a reference to the alarm at the specified index

	 */

	TASSrvAlarm&							AlarmAt(TInt aIndex);

	/**

	 * Return the number of alarms

	 */

	TInt									AlarmCount() const;

//

private:									// INTERNAL ENUMERATIONS

//

	/**

	 * The type of iterator

	 */

	enum TASSrvIteratorType

		{

		/**

		 * The secondary iterator which is only called (to check for matches)

		 * when the primary iterator identifies a matching alarm.

		 */

		EASSrvIteratorTypeSecondary			= 0,

		/**

		 * The main iterator which is first checked, before

		 * passing onto the child.

		 */

		EASSrvIteratorTypePrimary

		};

	/**

	 * Iterator panic

	 */

	enum TASSrvIteratorPanic

		{

		/**

		 * The iterator has reached the end of the alarm

		 * queue unexpectedly.

		 */

		EASSrvIteratorPanicNoNextAlarmForIterator = 0,

		/**

		 * An iterator is attempting to add itself as

		 * a secondary iterator.

		 */

		EASSrvIteratorPanicCyclicAttach,

		/**

		 * No secondary iterator is attached, but it 

		 * is expected to be so.

		 */

		EASSrvIteratorPanicNoneAttached,

		/**

		 * An iterator isn't correctly initialized.

		 */

		EASSrvIteratorPanicNotInitialized,

		/**

		 * The iterator type isn't correct

		 */

		EASSrvIteratorPanicTypeMismatch

		};

	/**

	 * Panic the Alarm Server

	 */

	static void								Panic(TASSrvIteratorPanic aPanic);

//

protected:									// MEMBER DATA

//

	/**

	 * The queue

	 */

	CASSrvAlarmQueue&						iQueue;

	/**

	 * The index of the current alarm which the iterator is

	 * pointing to.

	 */

	TInt									iCurrentIndex;

	/**

	 * The type of iterator

	 */

	TASSrvIteratorType						iType;

	/**

	 * A pointer to a secondary iterator. Not always initialised.

	 */

	RASSrvIteratorBase*						iAttachedIterator;

	};

#endif