/*

* Copyright (c) 2006-2007 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:  Processor object for running thumbnail requests

*

*/

#include "thumbnailrequestqueue.h"

#include "thumbnailrequestactive.h"

#include "thumbnaillog.h"

// ======== MEMBER FUNCTIONS ========

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::NewL()

// Two-phased constructor.

// ---------------------------------------------------------------------------

//

CThumbnailRequestQueue* CThumbnailRequestQueue::NewL()

    {

    CThumbnailRequestQueue* self = new( ELeave )CThumbnailRequestQueue();

    CleanupStack::PushL( self );

    self->ConstructL();

    CleanupStack::Pop( self );

    return self;

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::CThumbnailRequestQueue()

// C++ default constructor can NOT contain any code, that might leave.

// ---------------------------------------------------------------------------

//

CThumbnailRequestQueue::CThumbnailRequestQueue()

    {

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::ConstructL()

// Symbian 2nd phase constructor can leave.

// ---------------------------------------------------------------------------

//

void CThumbnailRequestQueue::ConstructL()

    {

    iActiveRequests = 0;

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::~CThumbnailRequestQueue()

// Destructor.

// ---------------------------------------------------------------------------

//

CThumbnailRequestQueue::~CThumbnailRequestQueue()

    {

    TN_DEBUG1( "CThumbnailRequestQueue::~CThumbnailRequestQueue()");

    iRequests.ResetAndDestroy();

    TN_DEBUG1( "CThumbnailRequestQueue::~CThumbnailRequestQueue() - All requests deleted");

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::Process()

// Activates next request if possible.

// ---------------------------------------------------------------------------

//

void CThumbnailRequestQueue::Process()

    {

    TN_DEBUG1( "CThumbnailRequestQueue::Process()");

    while ( (iActiveRequests < KMaxClientRequests) &&

            (iRequests.Count() > iActiveRequests) )

        {             

        CThumbnailRequestActive* selectedRequest = NULL;

        TInt priority( KMinTInt );

        TInt reqPriority;

        CThumbnailRequestActive* request = NULL;

        for ( TInt i = 0; i < iRequests.Count(); i++ )

           {

           request = iRequests[i];

           // this task is not yet activated or processed

           if( request && !request->RequestCompleted() && !request->IsRequestActive()  )

               {

               TN_DEBUG4( "CThumbnailRequestQueue::Process() - candidate at %d, id = %d, (0x%08x)", i, 

                       request->RequestId(), 

                       request);

               reqPriority = request->Priority();

               if ( reqPriority > priority )

                   {

                   priority = reqPriority;

                   selectedRequest = request;

                   }

               }

           }

        // activate selected

        if ( selectedRequest )

           {

           TN_DEBUG1( "CThumbnailRequestQueue::Process() - starting next request");

           iActiveRequests++;

           TRAPD(err, selectedRequest->StartL());

           if (err != KErrNone)

               {

               TN_DEBUG1( "CThumbnailRequestQueue::Process() - starting request failed");

               selectedRequest->StartError(err);

               }

           }

         else

            {

            break;

            }

        }

    TN_DEBUG3( "CThumbnailRequestQueue::Process() end - requests: %d, active requests: %d",

               iRequests.Count(), iActiveRequests );

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::AddRequestL()

// Adds new request to the queue.

// ---------------------------------------------------------------------------

//

void CThumbnailRequestQueue::AddRequestL( CThumbnailRequestActive* aRequest )

    {

    RemoveCompleted(NULL);

    iRequests.AppendL( aRequest );

    TN_DEBUG3( "CThumbnailRequestQueue::AddRequestL() end - requests: %d, active requests: %d",

               iRequests.Count(), iActiveRequests );

    }

void CThumbnailRequestQueue::RemoveCompleted( CThumbnailRequestActive* aRequestAO)

    {       

    //process completed queue and remove finished tasks

    for ( TInt i = iRequests.Count() -1; i >= 0 && iRequests.Count(); i-- )

         {

         CThumbnailRequestActive* request = iRequests[i];

         // remove completed task if it's not active anymore and not this

         if ( request->RequestCompleted() && !request->IsRequestActive() && aRequestAO != request)

             {

             // delete completed task

             TN_DEBUG3( "CThumbnailRequestQueue::RemoveCompleted() - deleted id = %d (0x%08x)", request->RequestId(), request);

             delete request;

             request = NULL;

             iRequests.Remove( i );

             }

         }

    if(!iRequests.Count())

        {

        iRequests.Compress();

        }

     TN_DEBUG3( "CThumbnailRequestQueue::RemoveCompleted() end - requests: %d, active requests: %d",

                    iRequests.Count(), iActiveRequests );

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::CancelRequest()

// Removes specific request from the queue.

// ---------------------------------------------------------------------------

//

TInt CThumbnailRequestQueue::CancelRequest( const TThumbnailRequestId aRequestId )

    {

    TN_DEBUG2( "CThumbnailRequestQueue::CancelRequest() - request ID: %d", aRequestId);

    TInt res = KErrNotFound;

    for ( TInt i = iRequests.Count(); --i >= 0; )

        {

        CThumbnailRequestActive* request = iRequests[i];

        if ( request->RequestId() == aRequestId )

            {

            if (iRequests[i]->IsActive()) 

                {

                // this doesn't yet actually cancel/complete the AO

                iRequests[i]->AsyncCancel();

                TN_DEBUG2( "CThumbnailRequestQueue::CancelRequest() - canceled request ID: %d", aRequestId);

                }

            else

                {

                delete request;

                request = NULL;

                iRequests.Remove( i );

                TN_DEBUG2( "CThumbnailRequestQueue::CancelRequest() - removed request ID: %d", aRequestId);

                }

            res = KErrNone;

            break;

            }

        }

	RemoveCompleted(NULL);

    Process();

    return res;

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::ChangeReqPriority()

// Changes priority of a request.

// ---------------------------------------------------------------------------

//

TInt CThumbnailRequestQueue::ChangePriority( const TThumbnailRequestId aRequestId,

                                             const TInt aNewPriority )

    {

    TN_DEBUG1( "CThumbnailRequestQueue::ChangePriority()");

    TInt err = KErrNotFound;

    const TInt count = iRequests.Count();

    for ( TInt i( 0 ); i < count; i++ )

        {

        if ( iRequests[i]->RequestId() == aRequestId )

            {

            iRequests[i]->ChangePriority( aNewPriority );

            err = KErrNone;

            break;

            }

        }

    return err;

    }

// ---------------------------------------------------------------------------

// CThumbnailRequestQueue::RequestComplete()

// Completes the request

// ---------------------------------------------------------------------------

//

void CThumbnailRequestQueue::RequestComplete(CThumbnailRequestActive* aRequestAO)

    {

    TN_DEBUG2( "CThumbnailRequestQueue::RequestComplete(0x%08x)", aRequestAO);

    iActiveRequests--;

    if(iActiveRequests <= -1)

        {

        iActiveRequests = 0;

        }

    RemoveCompleted( aRequestAO );

    Process();

    }

// End of file