/*

* Copyright (c) 2006 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: implementation of CXIMPContextEventQueue

 *

*/

#ifndef XIMPCONTEXTEVENTQUEUE_H

#define XIMPCONTEXTEVENTQUEUE_H

#include <e32base.h>

#include <ximpbase.h>

class CXIMPEventCapsule;

class CXIMPContextEventFilter;

class MXIMPEventQueueObserver;

class CXIMPApiEventBase;

class CXIMPRequestCompleteEventImp;

/**

 * Event queue for client to process.

 */

class CXIMPContextEventQueue : public CBase

    {

public:     // Constructors and destructors

    /**

     * Construction

     */

    IMPORT_C static CXIMPContextEventQueue* NewL();

    /**

     * Destruction

     */

    ~CXIMPContextEventQueue();

protected:  // Constructors

    /**

     * Construction

     */

    CXIMPContextEventQueue();

    /**

     * Construction

     */

    void ConstructL();

public: // New functions

    /**

     * Set event filter for filtering events

     * @param aFilter New filter.

     */

    IMPORT_C void SetEventFilter( CXIMPContextEventFilter& aFilter );

    /**

     * Start consuming events.

     * @param aQueueObserver Observer to notify when event is ready

     */

    IMPORT_C void StartConsuming( MXIMPEventQueueObserver& aQueueObserver );

    /**

     * Stop event consuming.

     */

    IMPORT_C void StopConsuming();

    /**

     * Check if there is elements.

     */

    IMPORT_C TBool HasElements() const;

    IMPORT_C void SelectTopEventIfNeededL();

    IMPORT_C const TDesC8& TopEventDataL();

    IMPORT_C TXIMPRequestId TopEventReqIdL();

    IMPORT_C void DropTopEvent();

    /** 

     * Add new event to queue.

     */

    void AddEventL( CXIMPEventCapsule& aEvent );

    /**

     * Activate new request complete event to queue.

     * @param aEvent Event to activate.

     */

    void ActivateRequestCompleteEvent( CXIMPRequestCompleteEventImp& aEvent );

    /**

     * Remove request complete event from queue

     * @param aEvent Event to remove

     */

    void RemoveRequestCompleteEvent( CXIMPRequestCompleteEventImp& aEvent );

    /**

     * Activate preserved event for sending.

     */

    void ActivatePreservedEventL( CXIMPApiEventBase& aEvent );

    /**

     * Get id of queue.

     * @return Id of queue.

     */

    inline TUint32 SessionIdOfQueue() const { return iId; }

    /**

     * Set id of queue

     * @param aId Id of queue.

     */

    inline void SetSessionIdOfQueue( TUint32 aId ) { iId = aId; }

private:    // Helpers

    /**

     * Clear queued events.

     */

    void ClearQueuedEvents();

    /**

     * Add new preserved event to queue.

     */

    void AddPreservedEventL( CXIMPApiEventBase& aEvent );

    /**

     * Find next ready event from array. Timestamp is used to choose first one.

     * iNextEventToGo is filled with oldest event. iNextEventToGo can be filled

     * with reference event before call.

     * @param aArray. Array of events to choose.

     * @return Index of found event in array

     */ 

    TInt FindNextEvent( RPointerArray< CXIMPEventCapsule >& aArray );

private:    // Data

    /**

     * Queue ID.

     */

    TUint32 iId;

    /**

     * Events array. Reference to events own.

     */

    RPointerArray< CXIMPEventCapsule > iEvents;

    /** 

     * Preserved events array. Reference to events own.

     */

    RPointerArray< CXIMPEventCapsule > iPreservedEvents;

    /**

     * Request complete events waiting for completion.

     */

    RPointerArray< CXIMPEventCapsule > iRequestCompleteEvents;    

    /**

     * Event filter. Own.

     */

    CXIMPContextEventFilter* iEventFilter;

    /**

     * Queue observer. Ref.

     */

    MXIMPEventQueueObserver* iObserver;

    /**

     * Helper variable to contain next event to go.

     */

    CXIMPEventCapsule* iNextEventToGo;

    /**

     * Timestamp for events.

     */

    TUint32 iTimeStamp;

    };

#endif      //  XIMPCONTEXTEVENTQUEUE_H