/*

* Copyright (c) 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:  Incremental OpenL() utility

*

*/

#include <e32base.h>

#include <mpxmessage.h>

#include <mpxcollectionpath.h>

#include <mpxcollectionutility.h>

#include <mpxcollectionmessagedefs.h>

#include <mpxmessagegeneraldefs.h>

#include <mpxmediageneraldefs.h>

#include <mpxcommandgeneraldefs.h>

#include <mpxincrementalopendefs.h>

#include <mpxmediacontainerdefs.h>

#include <mpxcollectionmessage.h>

#include <mpxlog.h>

#include <mpxcollectionopenlresultdef.h>

#include <mpxcollectioncommanddefs.h>

#include "mpxcollectionopenutility.h"

#include <e32math.h>

// CONSTANTS

const TInt KArrayGranularity = 5;

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

// static function to compare two datablock items

// used for sorting datablocks

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

//

static TInt CompareAsc( const TMPXOpenDataBlock& aFirst,

                        const TMPXOpenDataBlock& aSecond )

    {

    return aFirst.iOffset > aSecond.iOffset;

    }

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

// static function to compare two datablock items

// used for sorting datablocks

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

//

static TInt CompareDsc( const TMPXOpenDataBlock& aFirst,

                        const TMPXOpenDataBlock& aSecond )

    {

    return aFirst.iOffset < aSecond.iOffset;

    }

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

// Constructor

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

//

CMPXCollectionOpenUtility::CMPXCollectionOpenUtility( MMPXCollectionObserver* aObs,

                                                      TUid aMode ) 

                                                    : iFetchStep(EFetchNone),

                                                      iObs( aObs ),

                                                      iIncrementalChunks(KArrayGranularity),

                                                      iMode( aMode )

    {

    }

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

// 2nd Phase Constructor

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

//

void CMPXCollectionOpenUtility::ConstructL()

    {

    iTimer = CPeriodic::NewL( CActive::EPriorityStandard );

    }

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

// Two-Phased Constructor

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

//

EXPORT_C CMPXCollectionOpenUtility* CMPXCollectionOpenUtility::NewL( 

                                                 MMPXCollectionObserver* aObs,  

                                                 TUid aMode )

    {

    CMPXCollectionOpenUtility* self = 

                       new( ELeave ) CMPXCollectionOpenUtility( aObs, aMode );

    CleanupStack::PushL( self );

    self->ConstructL();

    CleanupStack::Pop( self );

    return self;

    }

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

// Destructor

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

//

CMPXCollectionOpenUtility::~CMPXCollectionOpenUtility()

    {

    if( iCollection )

      {

      iCollection->Close();

      }

    if( iTimer )

        {

        iTimer->Cancel();

        delete iTimer;

        }

    iIncrementalChunks.Close();

    delete iPath;

    delete iMedia;

    }

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

// Start the incremental fetching operation

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

//

EXPORT_C void CMPXCollectionOpenUtility::StartL( TArray<TMPXAttribute> /*aAttrs*/,

                                                 TInt aChunkSize,

                                                 TInt aOffset,

                                                 TDirection aDirection,

                                                 TMPXAttribute aKeyAttribute )

    {

    // Assert we are idle

    ASSERT( iFetchStep == EFetchNone );

    MPX_DEBUG1("CMPXCollectionOpenUtility::StartL <---");

    // Copy the operation data

    iFetchInfo.iSize = aChunkSize;

    iFetchInfo.iOffset = aOffset;

    iFetchDirection = aDirection;

    iKeyAttribute = aKeyAttribute;

    iData = NULL;

    delete iMedia;

    iMedia = NULL;

    delete iPath; 

    iPath = NULL;

    // Start reading

    iFetchStep = EFetchCount;

    RunNext();

    MPX_DEBUG1("CMPXCollectionOpenUtility::StartL --->");

    }

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

// Start the incremental fetching operation

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

//

EXPORT_C void CMPXCollectionOpenUtility::StartL( const CMPXCollectionPath& aPath,

                                                 TArray<TMPXAttribute> /*aAttrs*/,

                                                 TInt aChunkSize,

                                                 TInt aOffset,

                                                 TDirection aDirection,

                                                 TMPXAttribute aKeyAttribute )

    {

    // Assert we are idle and isolated mode

    MPX_ASSERT( iFetchStep == EFetchNone );

    MPX_ASSERT( iMode == KMcModeIsolated || iMode == KMcModePlaylist );

    MPX_DEBUG1("CMPXCollectionOpenUtility::StartL aPath <---");

    if( !iCollection )

        {

        iCollection = MMPXCollectionUtility::NewL( this, iMode ); 

        }

    // Copy the operation data

    MPX_DEBUG_PATH( aPath );

    iFetchInfo.iSize = aChunkSize;

    iFetchInfo.iOffset = aOffset;

    iFetchDirection = aDirection;

    iKeyAttribute = aKeyAttribute;

    iData = NULL;

    delete iMedia;

    iMedia = NULL;

    delete iPath;

    iPath = NULL;

    iPath = CMPXCollectionPath::NewL( aPath );

    // Start the fetch operation by setting up the context

    // to the correct path

    //

    iFetchStep = EFetchPath;

    RunNext();

    MPX_DEBUG1("CMPXCollectionOpenUtility::StartL --->");

    }

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

// Stop the incremental fetching operation

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

//

EXPORT_C void CMPXCollectionOpenUtility::Stop()

    {

    // Cancel all outstanding collection open requests

    MPX_DEBUG1("CMPXCollectionOpenUtility::Stop <---");

    if( iCollection )

        {

        iCollection->Collection().CancelRequest();

        }

    iTimer->Cancel();

    iIncrementalChunks.Reset();

    delete iMedia; 

    iMedia = NULL;

    iData = NULL;

    iFetchStep = EFetchNone;

    MPX_DEBUG1("CMPXCollectionOpenUtility::Stop --->");

    }

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

// Set the direction of the incremental fetching algorithm

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

//

EXPORT_C void CMPXCollectionOpenUtility::SetDirection( TDirection aDirection )

    {

    iFetchDirection = aDirection;

    if( iFetchStep == EFetchItems || iFetchStep == EFetchCommand )

        {

        TBool skipFirst = iFetchStep == EFetchCommand ? ETrue : EFalse;

        if( iFetchDirection == EFetchDown )

            {

            DoSortAscend( skipFirst );

            }

        else if( iFetchDirection == EFetchUp )

            {

            DoSortDescend( skipFirst );

            }

        else if( iFetchDirection == EFetchNormal )

            {

            TRAP_IGNORE( DoSortNormalL( skipFirst ) );

            }

        }

    }

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

// Set the fetching delay

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

//

EXPORT_C void CMPXCollectionOpenUtility::SetDelay( TInt aDelay )

    {

    iFetchDelay = aDelay;

    }

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

// Get the current path

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

//

EXPORT_C CMPXCollectionPath* CMPXCollectionOpenUtility::PathL()

    {

    CMPXCollectionPath* p(NULL);

    if( iCollection )

        {

        p = iCollection->Collection().PathL();

        }

    return p;

    }

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

// Handle Collection Message

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

//

void CMPXCollectionOpenUtility::HandleCollectionMessage(CMPXMessage* aMsg, TInt aErr)

    {

    if( aErr == KErrNone && aMsg )

        {

        TRAP_IGNORE( DoHandleCollectionMessageL( *aMsg ) );

        }

    }

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

 // HandleOpenL

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

 //

void CMPXCollectionOpenUtility::HandleOpenL(const CMPXMedia& aEntries,

                                            TInt aIndex,

                                            TBool aComplete,

                                            TInt aError)

    {

    if( iFetchStep == EFetchCount )

        {

        DoHandleCountL( aEntries, aIndex, aError );

        }

    else if( iFetchStep == EFetchItems )

        {

        DoHandleFetchItemsL( aEntries, aIndex, aError );

        }

    else

        {

        MPX_DEBUG1("CMPXCollectionOpenUtility::HandleOpenL EFetchPath/EFetchNone");

        iFetchStep = EFetchNone;

        iObs->HandleOpenL( aEntries, aIndex, aComplete, aError );

        }

    }

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

 // HandleOpenL

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

 //

void CMPXCollectionOpenUtility::HandleOpenL(const CMPXCollectionPlaylist& aPlaylist,

                                            TInt aError)

    {

    iObs->HandleOpenL( aPlaylist, aError );

    }

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

 // Handle Command Complete

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

 //

void CMPXCollectionOpenUtility::HandleCommandComplete(CMPXCommand* aCommandResult, 

                                                      TInt aError )

    {

    // Continue fetching items

    iFetchStep = EFetchItems;

    TRAP_IGNORE( DoHandleCommandCompleteL( *aCommandResult, aError ) );

    }

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

 // Handle Collection Media

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

 //

void CMPXCollectionOpenUtility::HandleCollectionMediaL(const CMPXMedia& /*aMedia*/, 

                                                       TInt /*aError*/)

    {

    // Do Nothing

    }

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

// Handle Collection Messages

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

//

void CMPXCollectionOpenUtility::DoHandleCollectionMessageL( const CMPXMessage& aMsg )

    {

    TMPXMessageId id( aMsg.ValueTObjectL<TMPXMessageId>( KMPXMessageGeneralId ) );

    if ( KMPXMessageGeneral == id &&

         iFetchStep == EFetchPath )

        {

        TInt event( aMsg.ValueTObjectL<TInt>( KMPXMessageGeneralEvent ) );

        TInt type( aMsg.ValueTObjectL<TInt>( KMPXMessageGeneralType ) );

        TInt data( aMsg.ValueTObjectL<TInt>( KMPXMessageGeneralData) );

        if ( event == TMPXCollectionMessage::EPathChanged && 

            type == EMcPathChangedByOpen )

            {

            MPX_DEBUG1("CMPXCollectionOpenUtility::DoHandleCollectionMessageL -- path opened");

            if( data == EMcContainerOpened)

                {

                iFetchStep = EFetchCount;

                RunNext();

                }

            else if( data == EMcItemOpened )  // only 2 cases

                {

                // Playlist, simply forward back to the observer

                iCollection->Collection().OpenL();

                iFetchStep = EFetchNone;

                }

            }

        }

    }

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

// Handle Command complete

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

//

void CMPXCollectionOpenUtility::DoHandleCommandCompleteL(CMPXCommand& /*aCommandResult*/, 

                                                         TInt aError)

    {

    if( iSelecting )

        {

        iSelecting = EFalse;

        }

    else if( aError == KErrNone )

        {

        // Get the data to return to the client, callback at HandleOpen()

        //

        // Implemented because the command tells the plugin to fetch the 

        // next block of data. However, the actual media object containing 

        // the current browse data may have been re-allocated. We cannot

        // assume that the data pointer remains the same. Therefore, it is

        // safer to refetch the data from the collection via OpenL()

        // This call should be FAST because the data has already been read at this point

        // 

        MPX_DEBUG1("CMPXCollectionOpenUtility::HandleCommandComplete OpenL <---");

        if( iIncrementalChunks.Count() == 1 || iFirstOpen )

            {

            DoSelectIndexL();

            }

        iCollection->Collection().OpenL();

        }

    else if( aError == KErrNotReady )

        {

        // Cache was deleted, need to restart the fetching operation

        Stop();

        iFetchStep = EFetchCount;

        iCollection->Collection().OpenL();

        }

    else // aError != KErrNone 

        {

        // Error occured, such as not supported

        MPX_DEBUG2("CMPXCollectionOpenUtility::HandleCommandComplete Error %i <---", aError);

        iFetchStep = EFetchNone;

        CMPXMedia* temp = CMPXMedia::NewL();

        CleanupStack::PushL( temp );    

        iObs->HandleOpenL( *temp, 0, ETrue, aError );

        CleanupStack::PopAndDestroy( temp );

        }    

    }

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

// Fetch count step

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

//

void CMPXCollectionOpenUtility::DoFetchCountL()

    {

    if( !iCollection )

        {

        iCollection = MMPXCollectionUtility::NewL( this, iMode ); 

        }

    // Ask for the total item count

    // Cache current iPath

    delete iPath;

    iPath = NULL;

    iPath = iCollection->Collection().PathL();

    iCollection->Collection().OpenL();

    }

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

// Handle the count step

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

//

void CMPXCollectionOpenUtility::DoHandleCountL(const CMPXMedia& aEntries, 

                                               TInt aIndex,

                                               TInt aError)

    {

    ASSERT( iFetchStep == EFetchCount );

    MPX_DEBUG2("CMPXCollectionOpenUtility::DoHandleCountL error %i <---", aError);

    TBool done(EFalse);

    if( aError == KErrNone )

        {

        // Do we support incremental for this OpenL()?

        //

        TBool supportIncremental(EFalse);

        if( aEntries.IsSupported( KMPXCollectionOpenLSupportsIncremental ) )

            {

            supportIncremental = aEntries.ValueTObjectL<TBool>( 

                                        KMPXCollectionOpenLSupportsIncremental );

            }

        if( supportIncremental )

            {

            TInt count(0);

            if( aEntries.IsSupported(KMPXMediaArrayCount) )

                {

                count = aEntries.ValueTObjectL<TInt>(KMPXMediaArrayCount);

                }

            if( iFetchInfo.iOffset == KErrNotFound )

                {

                // If the client did not specify an offset

                // we use the index the collection is pointing to

                // as the starting offset

                //

                iFetchInfo.iOffset = aIndex;

                }

            if( count > 0 )

                {

                // Perform the chunking here

                DoSetupChunksL( count );

                DoCompactTaskListL( aEntries );

                MPX_DEBUG2("CMPXCollectionOpenUtility::DoHandleCountL count %i", iIncrementalChunks.Count() );

                if( iIncrementalChunks.Count() )

                    {

                    // Start running the fetching algorithm

                    iFetchStep = EFetchItems; 

                    iFirstOpen = ETrue;

                    // Sync up the path, as there could have been items deleted

                    delete iPath;

                    iPath = NULL;

                    iPath = iCollection->Collection().PathL();

                    if( iObs )

                        {

                        iObs->HandleOpenL( aEntries, aIndex, EFalse, aError );

                        }

                    RunNext();

                    }

                else 

                    {

                    // Update index before returning

                    DoSelectIndexL();

                    iFetchStep = EFetchNone;

                    iCollection->Collection().OpenL();

                    done = EFalse;

                    }     

                }

            else

                {

                done = ETrue;

                }    

            }

        else // !supportIncremental

            {

            // Just return the results

            //

            MPX_DEBUG1("CMPXCollectionOpenUtility::DoHandleCountL incremental not supported");

            done = ETrue;    

            }        

        }

    if( (aError != KErrNone) || done )

        {

        // Stop the OpenL() operation

        iFetchStep = EFetchNone;