/*

* Copyright (c) 2005-2009 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:  Part of SyncML Data Synchronization Plug In Adapter

*

*/

#include "ChangeFinder.h"

#include "Logger.h"

const TUint KSnapshotFormatVersion ( 0xf0000001 ); // format version

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

// CChangeFinder::NewL

// Static function to create CChangeFider object(s)

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

CChangeFinder* CChangeFinder::NewL( MSmlSyncRelationship& aSyncRelationship, TKeyArrayFix aKey,

        TBool& aHasHistory, TInt aStreamUid )

    {

    CChangeFinder* self = new (ELeave) CChangeFinder( aSyncRelationship, aKey, aStreamUid );

    CleanupStack::PushL( self );

    self->ConstructL( aHasHistory );

    CleanupStack::Pop( self );

    return self;

    }

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

// CChangeFinder::CChangeFinder

// Constructor for the class

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

CChangeFinder::CChangeFinder( MSmlSyncRelationship& aSyncRelationship, TKeyArrayFix aKey, TInt aStreamUid ) :

iSyncRelationship( aSyncRelationship ),

iKey( aKey ),

iStreamUid( aStreamUid ),

iDataStoreUid( KErrNotFound )

    {

    }

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

// CChangeFinder::~CChangeFinder

// Destructor for the class, closes the ChangeFinder and writes snapshot to stream

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

CChangeFinder::~CChangeFinder()

    {

    LOGGER_ENTERFN( "CChangeFinder::~CChangeFinder" );

    TInt error;

    TRAP( error, CloseL() );

    if ( error != KErrNone )

        {

        LOGGER_WRITE( "CChangeFinder::~CChangeFinder, CloseL failed." );

        }

    delete iCurrentSnapshot;

    delete iOldSnapshot;

    LOGGER_LEAVEFN( "CChangeFinder::~CChangeFinder" );

    }

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

// CChangeFinder::ConstructL

// 2nd phase constructor for the class, reads snapshot from stream

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

void CChangeFinder::ConstructL( TBool& aHasHistory )

    {

    LOGGER_ENTERFN( "CChangeFinder::ConstructL" );

    aHasHistory = EFalse;

    RReadStream readStream;

    TUid streamId;

    streamId.iUid = iStreamUid;

    aHasHistory = iSyncRelationship.IsStreamPresentL(streamId);

    if (aHasHistory)

        {

        iSyncRelationship.OpenReadStreamLC(readStream, streamId);

        // Read the index, first create snapshot array

        iOldSnapshot = new (ELeave) CSnapshotArray( KSnapshotGranularity );

        // Read used format version

        TUint formatVer = readStream.ReadUint32L();

        if ( formatVer != KSnapshotFormatVersion )

            {

            // Wrong version, do not try to import data

            LOGGER_WRITE("CChangeFinder::ConstructL, Wrong format version -> no history");

            aHasHistory = EFalse;

            CleanupStack::PopAndDestroy(); // readStream

            LOGGER_LEAVEFN("CChangeFinder::ConstructL");

            return;

            }

        // Read item count

        TInt count = readStream.ReadUint32L();

        // Read items

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

            {

            TSnapshotItem item;

            item.InternalizeL( readStream );

            iOldSnapshot->InsertIsqL( item, iKey );

            }

        readStream.Close();

        readStream.Pop();

        }

    else

        {

        LOGGER_WRITE("CChangeFinder::ConstructL, no sync history.");

        }

    LOGGER_LEAVEFN("CChangeFinder::ConstructL");

    }

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

// CChangeFinder::CloseL

// Closes ChangeFinder object and writes snapshot to stream

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

void CChangeFinder::CloseL()

    {

    LOGGER_ENTERFN( "CChangeFinder::CloseL" );

    // Write to stream

    RWriteStream writeStream;

    TUid streamId;

    streamId.iUid = iStreamUid; 

    // Open write stream

    iSyncRelationship.OpenWriteStreamLC( writeStream, streamId );

    // Write used format version

    writeStream.WriteUint32L( KSnapshotFormatVersion );

    // Write item count

    TInt count(0);

    if ( iOldSnapshot )

        {

        count = iOldSnapshot->Count();

        }

    writeStream.WriteUint32L(count);

    // Write items

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

        {

        const TSnapshotItem& item = iOldSnapshot->At( i );

        item.ExternalizeL( writeStream );

        }

    writeStream.CommitL();

    writeStream.Close();

    writeStream.Pop();

    LOGGER_LEAVEFN( "CChangeFinder::CloseL" );

    }

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

// CChangeFinder::ResetL

// Resets synchronization history, all contetn is considered new after this call

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

void CChangeFinder::ResetL()

    {

    LOGGER_ENTERFN( "CChangeFinder::ResetL" );

    // Delete old change information

    if ( iOldSnapshot )

        {

        LOGGER_WRITE("iOldSnapshot->Reset()");

        iOldSnapshot->Reset();

        }

    // Write 'null' data to file, 

    // this removes change history from the file

    CloseL();

    LOGGER_LEAVEFN( "CChangeFinder::ResetL" );

    }

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

// CChangeFinder::FindChangedItemsL

// Compares snapshots, finds changed items

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

void CChangeFinder::FindChangedItemsL( CNSmlDataItemUidSet& aChangedUids )

    {   

    LOGGER_ENTERFN( "CChangeFinder::FindChangedItemsL" );

    if ( !iCurrentSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::FindChangedItemsL leaved, no current snapshot." );

        User::Leave( KErrNotFound );

        }

    if ( !iOldSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::FindChangedItemsL leaved, no old snapshot." );

        User::Leave( KErrNotFound );

        }

    TInt index;

    TInt count = iCurrentSnapshot->Count();

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

        {

        const TSnapshotItem& currentItem = iCurrentSnapshot->At( i );

        // Find this entry from the old snapshot

        if ( iOldSnapshot->FindIsq( currentItem, iKey, index ) == KErrNone)

            {

            // This is the old item

            TSnapshotItem& oldItem = iOldSnapshot->At( index );

            // Compare times to see whether this was changed or item was read

            if ( ( oldItem.LastChangedDate() != currentItem.LastChangedDate() )

                || ( oldItem.Unread() && !currentItem.Unread() )

                || ( !oldItem.Unread() && currentItem.Unread() )

                || ( oldItem.FolderName().Compare( currentItem.FolderName() ) != 0 ) )

                {

                aChangedUids.AddItem( currentItem.ItemId() );

                LOGGER_WRITE_1( "Item %d was changed.", currentItem.ItemId() );  

                }

            }

        }

    LOGGER_LEAVEFN( "CChangeFinder::FindChangedItemsL" );

    }

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

// CChangeFinder::FindDeletedItemsL

// Compares snapshots, finds deleted items

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

void CChangeFinder::FindDeletedItemsL( CNSmlDataItemUidSet& aDeletedUids )

    {

    LOGGER_ENTERFN( "CChangeFinder::FindDeletedItemsL" );

    if ( !iOldSnapshot )

        {

        LOGGER_LEAVEFN( "CChangeFinder::FindDeletedItemsL leaved, no old snapshot." );

        User::Leave( KErrNotFound );

        }

    TInt index;

    TInt count = iOldSnapshot->Count();

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

        {

        const TSnapshotItem& currentItem = iOldSnapshot->At( i );

        // If there's no current snapshot, this definately is deleted item

        if ( !iCurrentSnapshot )

            {

            aDeletedUids.AddItem( currentItem.ItemId() );

            LOGGER_WRITE_1( "Item %d was deleted.", currentItem.ItemId() );

            }

        // It is also new if it doesn't exist int the current snapshot.

        else if ( iCurrentSnapshot->FindIsq( currentItem, iKey, index ) != KErrNone )

            {

            aDeletedUids.AddItem( currentItem.ItemId() );

            LOGGER_WRITE_1( "Item %d was deleted.", currentItem.ItemId() );

            }       

        }

    LOGGER_LEAVEFN( "CChangeFinder::FindDeletedItemsL" );

    }

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

// CChangeFinder::FindNewItemsL

// Compares snapshots, finds new items

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

void CChangeFinder::FindNewItemsL( CNSmlDataItemUidSet& aNewUids )

    {

    LOGGER_ENTERFN( "CChangeFinder::FindNewItemsL" );

    if ( !iCurrentSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::FindNewItemsL leaved, no current snapshot." );

        User::Leave( KErrNotFound );

        }

    TInt index;

    TInt count = iCurrentSnapshot->Count();

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

        {

        const TSnapshotItem& currentItem = iCurrentSnapshot->At( i );

        // If there's no old snapshot, all items are new

        if ( !iOldSnapshot )

            {

            aNewUids.AddItem( currentItem.ItemId() );

            LOGGER_WRITE_1( "Item %d was new.", currentItem.ItemId() );

            }

        // It is also new if it doesn't exist int the old snapshot.

        else if ( iOldSnapshot->FindIsq( currentItem, iKey, index ) != KErrNone )

            {

            aNewUids.AddItem( currentItem.ItemId() );

            LOGGER_WRITE_1( "Item %d was new.", currentItem.ItemId() );

            }       

        }

    LOGGER_LEAVEFN( "CChangeFinder::FindNewItemsL" );

    }

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

// CChangeFinder::FindMovedItemsL

// Compares snapshots, finds moved items

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

void CChangeFinder::FindMovedItemsL( CNSmlDataItemUidSet& aMovedUids )

    {

    LOGGER_ENTERFN( "CChangeFinder::FindMovedItemsL" );

    if ( !iCurrentSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::FindMovedItemsL leaved, no current snapshot." );

        User::Leave( KErrNotFound );

        }

    if ( !iOldSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::FindMovedItemsL leaved, no old snapshot." );

        User::Leave( KErrNotFound );

        }

    TInt index;

    TInt count = iCurrentSnapshot->Count();

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

        {

        const TSnapshotItem& currentItem = iCurrentSnapshot->At( i );

        // Find this entry from the old snapshot

        if(iOldSnapshot->FindIsq( currentItem, iKey, index ) == KErrNone)

            {

            // This is the old item

            TSnapshotItem& oldItem = iOldSnapshot->At( index );

            // Report only moved items in which only parent id has been changed

            if ( oldItem.ParentId() != currentItem.ParentId()

                && oldItem.LastChangedDate() == currentItem.LastChangedDate()

                && !(oldItem.Unread() && !currentItem.Unread() )

                && !(!oldItem.Unread() && currentItem.Unread() ) )

                {

                aMovedUids.AddItem( currentItem.ItemId() );

                LOGGER_WRITE_1( "Item %d was moved.", currentItem.ItemId() );

                }

            }       

        }

    LOGGER_LEAVEFN( "CChangeFinder::FindMovedItemsL" );     

    }

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

// CChangeFinder::ItemAddedL

// Adds item to snapshot, this item is no longer considered new

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

void CChangeFinder::ItemAddedL( const TSnapshotItem& aItem )

    {

    LOGGER_ENTERFN( "CChangeFinder::ItemAddedL" );

    // Add this to old snapshot, if there's no old snapshot it must be created

    if ( !iOldSnapshot )

        {

        iOldSnapshot = new (ELeave) CSnapshotArray( KSnapshotGranularity );

        }

    LOGGER_WRITE_1( "Adding item %d.", aItem.ItemId() );

    TRAPD( error, iOldSnapshot->InsertIsqL( aItem, iKey ) );

    if ( error == KErrAlreadyExists )

        {

        // It was already committed, no actions required

        LOGGER_WRITE( "iOldSnapshot->InsertIsqL leaved with KErrAlreadyExists" );

        }

    else if ( error != KErrNone )

        {

        LOGGER_WRITE_1( "iOldSnapshot->InsertIsqL leaved with %d.", error );

        User::Leave( error );

        }

    LOGGER_LEAVEFN( "CChangeFinder::ItemAddedL" );

    }

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

// CChangeFinder::ItemDeletedL

// Removes item to snapshot, this item is no longer considered deleted

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

void CChangeFinder::ItemDeletedL( const TSnapshotItem& aItem )

    {

    LOGGER_ENTERFN( "CChangeFinder::ItemDeleted" );

    LOGGER_WRITE_1( "deleting item %d.", aItem.ItemId() );

    if ( !iOldSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::ItemDeleted leaved, no old snapshot." );

        User::Leave( KErrNotFound );

        }

    // Delete item from the old snapshot

    TInt index;

    if ( iOldSnapshot->FindIsq( aItem, iKey, index ) == KErrNone )

        {

        iOldSnapshot->Delete( index );

        }

    else // Skip, there wasn't such entry

        {

        LOGGER_WRITE( "iOldSnapshot->FindIsq, item was not found." );

        }  

    LOGGER_LEAVEFN( "CChangeFinder::ItemDeleted" );

    }

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

// CChangeFinder::ItemUpdatedL

// Updates item to snapshot, this item is no longer considered changed

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

void CChangeFinder::ItemUpdatedL( const TSnapshotItem& aItem )

    {

    LOGGER_ENTERFN( "CChangeFinder::ItemUpdatedL" );

    LOGGER_WRITE_1( "Updating item %d.", aItem.ItemId() );

    // There must be such entry in the snapshot after this

    // If there isn't old snapshot, we'll create it and add the item

    if ( !iOldSnapshot )

        {

        iOldSnapshot = new (ELeave) CSnapshotArray( KSnapshotGranularity );

        ItemAddedL( aItem );

        }

    else

        {

        // Update item in the old snapshot

        TInt index;

        if ( iOldSnapshot->FindIsq( aItem, iKey, index ) == KErrNone )

            {

            TSnapshotItem& oldItem = iOldSnapshot->At( index );

            oldItem = aItem;

            }

        else 

            {

            // There was old snapshot but no such item. Let's add it

            ItemAddedL( aItem );

            }

        }

    LOGGER_LEAVEFN( "CChangeFinder::ItemUpdatedL" );

    }

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

// CChangeFinder::ItemMovedL

// Moves item within snapshot, this item is no longer considered moved

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

void CChangeFinder::ItemMovedL( const TSnapshotItem& aItem )

    {

    LOGGER_ENTERFN( "CChangeFinder::ItemMovedL" );

    LOGGER_WRITE_1( "Moving item %d.", aItem.ItemId() );

    // There must be such entry in the snapshot after this

    // If there isn't old snapshot, we'll create it and add the item

    if ( !iOldSnapshot )

        {

        iOldSnapshot = new (ELeave) CSnapshotArray( KSnapshotGranularity );

        ItemAddedL( aItem );

        }

    else

        {

        // Update item's parent in the old snapshot

        TInt index;

        if ( iOldSnapshot->FindIsq( aItem, iKey, index ) == KErrNone )

            {

            TSnapshotItem& oldItem = iOldSnapshot->At( index );

            oldItem.SetParentId( aItem.ParentId() );

            }

        else 

            {

            // There was old snapshot but no such item. Let's add it

            ItemAddedL( aItem );

            }   

        }

    LOGGER_LEAVEFN("CChangeFinder::ItemMovedL");    

    }

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

// CChangeFinder::CommitChangesL

// Commits current changes to snapshot

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

void CChangeFinder::CommitChangesL()

    {

    LOGGER_ENTERFN( "CChangeFinder::CommitChangesL" );

    if ( !iCurrentSnapshot )

        {

        LOGGER_WRITE( "CChangeFinder::CommitChangesL leaved, current snapshot missing." );

        User::Leave( KErrNotFound );

        }

    if ( !iOldSnapshot )

        {

        iOldSnapshot = new (ELeave) CSnapshotArray( KSnapshotGranularity );

        }

    // Delete everything from the old snapshot

    iOldSnapshot->Reset();

    // Loop through all the items in current snapshot

    TInt count = iCurrentSnapshot->Count();

    // Copy everything from current to old snapshot

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

        {   

        const TSnapshotItem& newItem = iCurrentSnapshot->At( i );

        // Commit it to the old array.

        TRAPD( error, iOldSnapshot->InsertIsqL( newItem, iKey ) );

        if ( error == KErrAlreadyExists )

            {

            // It was already committed, this is an internal error of change finder

            LOGGER_WRITE( "iOldSnapshot->InsertIsqL leaved with KErrAlreadyExists." );

            User::Leave( error );

            }