/*

* Copyright (c) 2003 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:  This module contains the implementation of CCbsRecDecoder class 

*                member functions.

*    

*                This class represents a collector, which stores pages of multipaged 

*                messages. Complete messages are assembled and returned back to 

*                the caller of CollectL() method.

*  

*                CCbsRecCollector stores message pages in a number of dynamic arrays.

*                If all but one page of a message are present in collector, and

*                the remaining page is received, the pages will be assembled and

*                the corresponding message chain deleted.

* 

*                The maximum number of incomplete messages stored in collector at once

*                is fixed and determined by KMaxCollectorMessages in CCbsRecCollector.cpp.

* 

*                CCbsRecCollector implements a circular list to contain message.

*                Each incomplete message occupies a slot in this list. If the list already

*                contains KMaxCollectorMessages messages, the next received multipaged

*                message will delete all received pages of the oldest message in list.

* 

*                On receival of a message page, the collector compares network information

*                (PLMN, LAC, CellId) of both messages to decide whether pages are of

*                the same message. In short, for pages to be of the same message

*                their network information have to meet the requirements set by the 

*                geographical scope of the already collected page.

*                See ETSI GSM 03.41 for a detailed description. 

*

*/

// INCLUDE FILES

#include "CbsServerPanic.h"

#include "CCbsRecCollector.h"

#include "CCbsRecMessage.h"

#include "CCbsMessageFactory.h"

#include "CCbsMessageCleanUpTimer.h"

#include "CbsLogger.h"

// CONSTANTS

// Maximum number of pages in a single CB message.

const TInt KMaxMessagePages = 15;

// Maximum number of partial messages contained in the collector list.

const TInt KMaxCollectorMessages = 10;

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

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

// CCbsRecCollector::CCbsRecCollector

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

// might leave.

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

//

CCbsRecCollector::CCbsRecCollector( CCbsMessageFactory& aFactory )

    : iRootNodeIterator( 0 ),

    iFactory( aFactory )

    {

    }

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

// CCbsRecCollector::ConstructL

// Symbian 2nd phase constructor can leave.

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

//

void CCbsRecCollector::ConstructL()

    {

    CBSLOGSTRING("CBSSERVER: >>> CCbsRecCollector::ConstructL()");

    // initialize the root node array

    iRootNodeArray = new ( ELeave ) CArrayPtrFlat< CMessageBuffer >

        ( KMaxCollectorMessages );

    iRootNodeArray->SetReserveL( KMaxCollectorMessages );

    iMessageCleanupTimerArray = new ( ELeave ) CArrayPtrFlat< CCbsMessageCleanupTimer >

        ( KMaxCollectorMessages );

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

        {

        CMessageBuffer* array = new ( ELeave )

            CMessageBuffer( KMaxMessagePages );

        CleanupStack::PushL( array );

        iRootNodeArray->AppendL( array );

		CCbsMessageCleanupTimer* messageCleanUpTimer = CCbsMessageCleanupTimer::NewL( *this, *array );

		iMessageCleanupTimerArray->AppendL( messageCleanUpTimer );

        CleanupStack::Pop(); // array

        }

    CBSLOGSTRING("CBSSERVER: <<< CCbsRecCollector::ConstructL()");

    }

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

// CCbsRecCollector::NewL

// Two-phased constructor.

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

//

 CCbsRecCollector* CCbsRecCollector::NewL( CCbsMessageFactory& aFactory )

    {

    CBSLOGSTRING("CBSSERVER: >>> CCbsRecCollector::NewL()");

    CCbsRecCollector* self = new ( ELeave ) CCbsRecCollector( aFactory );

    CleanupStack::PushL( self );

    self->ConstructL();

    CleanupStack::Pop();

    CBSLOGSTRING("CBSSERVER: <<< CCbsRecCollector::NewL()");

    return self;

    }

// Destructor

CCbsRecCollector::~CCbsRecCollector()

    {

    CBSLOGSTRING("CBSSERVER: >>> CCbsRecCollector::~CCbsRecCollector()");

    if ( iRootNodeArray )

        {

        TInt rootArrayLength( iRootNodeArray->Count() );

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

            {

            iRootNodeArray->At( i )->ResetAndDestroy();

            }

        iRootNodeArray->ResetAndDestroy();

        delete iRootNodeArray;

        }

    if ( iMessageCleanupTimerArray )

        {

        iMessageCleanupTimerArray->ResetAndDestroy();

        delete iMessageCleanupTimerArray;

        }

    CBSLOGSTRING("CBSSERVER: <<< CCbsRecCollector::~CCbsRecCollector()");

    }

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

// CCbsRecCollector::CollectL

// Adds a message to the location pointed by iRootNodeIterator.

//   

// Checks if all pages of message are present. If all pages

// are present, sets aCompleted to ECbsMessageComplete,

// combines message pages into a single message, destroys

// pages from the list and returns the complete message

// to caller in aMessage.

// Algorithm:

//   1.  Check if other pages of this message exist in list.

//       (serial number and message identifier match)

//   2.  True: Check if the other messages in chain need

//       to be deleted. This is based on geographical scope

//       and network information.

//       Add this message to the correct message chain.

//       False: Add this message to the chain pointed

//       by the iRootNodeIterator.

//   3.  Seek out the position in the chosed message chain so that

//       the page number sequence remains ordered (1, 2, .., n)

//   4.  Add the page to the correct position in chain.

//   5.  Check if all pages of this message exist (number count).

//   6.  True: Combine message pages into a single message

//       and return this page to the caller. Set aCompleted

//       to ECbsMessageComplete.

//       False: Set aCompleted to ECbsMessageIncomplete.

//

// Note: Ownership of aMessage assumed. aMessage assumed to be

// on cleanup stack.

// (other items were commented in a header).

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

//  

CCbsMessage* CCbsRecCollector::CollectL( 

    CCbsMessage* aMessage, TInt aMessageType )  

    {

	CBSLOGSTRING("CBSSERVER: >>> CCbsRecCollector::CollectL()");

    // 1.

    CMessageBuffer* array = FindChainContainingPage( *aMessage );

    CCbsMessage* mergedMessage = NULL;

    if ( array  ) 

        {		

        CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): array != NULL");

        // 2. (True), 3.

        __ASSERT_DEBUG( array->Count() > 0, 

            CbsServerPanic( ECbsCollectorArrayEmpty ) );

        // Check geographical scope and network info to decide whether

        // existing pages in this chain should be deleted.

        TBool preserveExistingPages( 

            CheckPageAreaInfoMatch( *aMessage, *array->At( 0 ) ) );

        CBSLOGSTRING2("CBSSERVER: CCbsRecCollector::CollectL(): preserveExistingPages: %d", preserveExistingPages );

        if ( preserveExistingPages ) 

            {			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Adding msg to chain...");

            // aMessage is deleted, if it is a duplicate.

            AddMessageToChainL( aMessage, *array );			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Adding msg to chain OK.");

            }

        else 

            {			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Deleting chain...");

            DeleteChainL( *array );			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Deleting chain OK.");

            array->InsertL( 0, aMessage );			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Msg added to array.");

            }

        // aMessage, ownership transferred to msg chain or

        // aMessage has been deleted by AddMessageToChainL

        CleanupStack::Pop(); 

        // 5. Check if this chain contains all pages of the message.

        if ( AllPagesPresent( *array ) )

            {			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): All pages present, merging...");

            // 6. merge creates a new copy of this message

            // leaves a pointer to msg to cleanup stack

            mergedMessage = MergePagesLC( *array ); // on CS			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Merging OK.");

			// we stop timer if its livecast message

			if ( aMessageType == ECbsMessageLivecast )

				{				

                CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Msg type == ECbsMessageLivecast, stopping timer.");

				TKeyArrayFix key(0, ECmpTUint16);

				TInt index;

				iRootNodeArray->Find( array, key, index);

				iMessageCleanupTimerArray->At( index )->StopTimer();

                CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Timer stopped.");

				}

			CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Deleting chain...");

            DeleteChainL( *array );

			CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Deleting chain OK.");

            CleanupStack::Pop(); // mergedMessage

            }

        }

    else

        {		

        CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): array == NULL");

		// if message pagenumber does not start from 1, its not inserted to chain.

		if ( aMessage->ThisPage () == 1 ) 

			{			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): aMessage->ThisPage () == 1");

			// 2. (False)

			// add this page as the first node in chain pointed by 

			// iRootNodeIterator. Delete any pages contained in the chain

			// occuping this location first.

			array = iRootNodeArray->At( iRootNodeIterator );

			DeleteChainL( *array );

			array->InsertL( 0, aMessage );

			CleanupStack::Pop(); // aMessage, ownership transferred to msg chain.

			iRootNodeIterator++;

			// Return to the first message, if passed the

			// maximum messages.

			iRootNodeIterator %= KMaxCollectorMessages;

			if ( aMessageType == ECbsMessageLivecast )

				{				

                CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): aMessageType == ECbsMessageLivecast");

				// start timeout timer for livecast message

				TKeyArrayFix key(0, ECmpTUint16);

				TInt index;

				iRootNodeArray->Find( array, key, index);

				iMessageCleanupTimerArray->At( index )->StartTimer();

                CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): Timer started.");

				}

			}

		else

			{			

            CBSLOGSTRING("CBSSERVER: CCbsRecCollector::CollectL(): CleanupStack::Pop()");

			CleanupStack::Pop();

			}

        }

    // mergedMessage == NULL if msg not completed,

    // otherwise return the complete message

	CBSLOGSTRING("CBSSERVER: <<< CCbsRecCollector::CollectL(), returning mergedMessage.");

    return mergedMessage;

    }

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

// CCbsRecCollector::DeleteChainL

// Deletes all message pages contained in aArray.

// (other items were commented in a header).

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

//  

void CCbsRecCollector::DeleteChainL( 

    CMessageBuffer& aArray ) const

    {

    aArray.ResetAndDestroy();

    }

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

// CCbsRecCollector::AllPagesPresent

// Returns ETrue if all pages of the message of aArray are present.

// Counts pages in message chain aArray and compares the result

// against the total number of pages in the message.

// (other items were commented in a header).

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

// 

TBool CCbsRecCollector::AllPagesPresent( 

    const CMessageBuffer& aArray ) const

    {

    TBool result( ETrue );

    if ( TUint( aArray.Count() ) < aArray.At( 0 )->TotalPages() )

        {

        result = EFalse;        

        }

    return result;

    }

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

// CCbsRecCollector::MergePagesLC

// Returns a complete message in aMessage.

// Merges all pages in message chain aArray and returns

// a pointer to the resulting assembled message. The pointer

// is also left on the cleanup stack.

// (other items were commented in a header).

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

//

CCbsMessage* CCbsRecCollector::MergePagesLC( 

    CMessageBuffer& aArray ) const

    {

    if ( aArray.Count() <= 0 )

        {

        User::Leave( KErrNotFound );

        }

    // Create a new message based on first message page in the chain.

    CCbsMessage* message = iFactory.CreateMessageL( *aArray.At( 0 ) );

    CleanupStack::PushL( message ); // left on cleanup stack

    // Traverse through the chain and merge contents.

    TInt length( 0 );

    TInt count( aArray.Count() );

    // If this is a Livecast message, use the 8-bit representation

    // (message not decoded).

    if ( message->IsLivecastMessage() )

        {

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

            {

            length += aArray.At( j )->Contents8().Length();

            }

        __ASSERT_DEBUG( length >= 0, CbsServerPanic( ECbsCollectorMergeFailed ) );

        message->ReserveContentSize8L( length );

        count = aArray.Count();

        for ( TInt i( 1 ); i < count; i++ ) 

            {

            message->AppendContent8( aArray.At( i )->Contents8() );

            }

        }

    // Else use the 16-bit representation (message already decoded)

    else

        {

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

            {

            length += aArray.At( j )->Contents().Length();

            }

	    __ASSERT_DEBUG( length >= 0, CbsServerPanic( ECbsCollectorMergeFailed ) );

	    message->ReserveContentSizeL( length );

	    count = aArray.Count();

    // Append the rest of the pages (first page handled earlier)

	    for ( TInt i( 1 ); i < count; i++ ) 

	        {

	        message->AppendContent( aArray.At( i )->Contents() );

	        }

        }

    return message;

    }

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

// CCbsRecCollector::FindChainContainingPage

// Returns the buffer containing pages of same message.

// Finds and returns a message chain which already contains pages

// of aMessage's message. If none is found, NULL is returned.

// (other items were commented in a header).

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

//

CMessageBuffer* CCbsRecCollector::FindChainContainingPage( 

    const CCbsMessage& aMessage ) const

    {

    TBool quitSeek( EFalse );

    TInt seekIterator( 0 );

    TCbsDbMessageKey key( aMessage.Key() );

    TCbsDbTopicNumber topicNumber( aMessage.TopicNumber() );

    CMessageBuffer* array = NULL;

    // find out if the root array contains pages of this message

    while ( ( seekIterator < KMaxCollectorMessages ) && !quitSeek  )

        {

        array = iRootNodeArray->At( seekIterator );

        if ( array->Count() > 0 ) 

            {

            CCbsMessage* msg = array->At( 0 );

            if ( key == msg->Key() && topicNumber == msg->TopicNumber() )

                {

                quitSeek = ETrue;

                }

            }

        seekIterator++;

        }

    if ( !quitSeek )

        {

        array = NULL;

        }

    return array;

    }

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

// CCbsRecCollector::AddMessageToChainL

// Adds message page aMessage to the correct position in message chain aArray

//        

// Message chains are ordered in ascending page number order.

// Duplicate pages are not accepted.

//

// Ownership of aMessage is transferred to aArray, if the given page

// hasn't been already collected. The given page will be deleted,

// if it already exists in the chain.

// (other items were commented in a header).

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

//

void CCbsRecCollector::AddMessageToChainL( 

    CCbsMessage* aMessage, 

    CMessageBuffer& aArray ) const

    {

    // Find out a position for this page in the chain.

    TInt chainLength( aArray.Count() );    

    TInt insertPosition( -1 );

    TBool duplicate( EFalse );

    for ( TInt i( 0 ); ( i < chainLength ) && !duplicate; i++ )

        {

        CCbsMessage* msg = aArray.At( i );

        if ( insertPosition == -1 && msg->ThisPage() > aMessage->ThisPage() )

            {

            insertPosition = i;

            }

        else if ( msg->ThisPage() == aMessage->ThisPage() )

            {

            duplicate = ETrue; // This page has been already collected

            delete aMessage;

            }

        }

    // If this message was not a duplicate, add it to the chain

    if ( !duplicate )

        {

        if ( insertPosition == -1 )

            {

            aArray.AppendL( aMessage );

            }

        else

            {

            aArray.InsertL( insertPosition, aMessage );

            }

        }    

    }

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

// CCbsRecCollector::CheckPageAreaInfoMatch

// Checks if these pages can be merged. Returns ETrue, if merging is acceptable.

//   

// Decision is based network information and geographical scope of 

// pages. Network information consists of cell id, location area code

// and operator id.

// 

// Assumption: aPage1 and aPage have identical message

// identifiers and serial numbers. 

// Returns ETrue if the pages are of same message.

// On EFalse previous pages should be deleted.

// (other items were commented in a header).

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

//

TBool CCbsRecCollector::CheckPageAreaInfoMatch( 

    const CCbsMessage& aPage1, 

    const CCbsMessage& aPage2 ) const

    {   

    RMobilePhone::TMobilePhoneNetworkInfoV1 info1;

    RMobilePhone::TMobilePhoneNetworkInfoV1 info2;

    aPage1.GetPLMN( info1 );

    aPage2.GetPLMN( info2 );

    TBool result( EFalse );

    if ( info1.iCountryCode == KRecMessageNoNetworkInfo || 

        info2.iCountryCode == KRecMessageNoNetworkInfo )

        {

        // Network info is unavailable; we must assume that the aPage1

        // is of the same page area as aPage2, so we return ETrue

        // unconditionally.

        result = ETrue;

        }

    if ( info1.iCountryCode == info2.iCountryCode && 

        info1.iNetworkId == info2.iNetworkId )