src/app/ClusterStateCache.cpp - third_party/github/project-chip/connectedhomeip - Git at Google

 /*
  *
  *    Copyright (c) 2021 Project CHIP Authors
  *    All rights reserved.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
  *    You may obtain a copy of the License at
  *
  *        http://www.apache.org/licenses/LICENSE-2.0
  *
  *    Unless required by applicable law or agreed to in writing, software
  *    distributed under the License is distributed on an "AS IS" BASIS,
  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *    See the License for the specific language governing permissions and
  *    limitations under the License.
  */

 #include "system/SystemPacketBuffer.h"
 #include <app/ClusterStateCache.h>
 #include <app/InteractionModelEngine.h>
 #include <tuple>

 namespace chip {
 namespace app {

 CHIP_ERROR ClusterStateCache::GetElementTLVSize(TLV::TLVReader * apData, size_t & aSize)
 {
     Platform::ScopedMemoryBufferWithSize<uint8_t> backingBuffer;
     TLV::TLVReader reader;
     reader.Init(*apData);
     size_t totalBufSize = reader.GetTotalLength();
     backingBuffer.Calloc(totalBufSize);
     VerifyOrReturnError(backingBuffer.Get() != nullptr, CHIP_ERROR_NO_MEMORY);
     TLV::ScopedBufferTLVWriter writer(std::move(backingBuffer), totalBufSize);
     ReturnErrorOnFailure(writer.CopyElement(TLV::AnonymousTag(), reader));
     aSize = writer.GetLengthWritten();
     ReturnErrorOnFailure(writer.Finalize(backingBuffer));
     return CHIP_NO_ERROR;
 }

 CHIP_ERROR ClusterStateCache::UpdateCache(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apData,
                                           const StatusIB & aStatus)
 {
     AttributeState state;
     bool endpointIsNew = false;

     if (mCache.find(aPath.mEndpointId) == mCache.end())
     {
         //
         // Since we might potentially be creating a new entry at mCache[aPath.mEndpointId][aPath.mClusterId] that
         // wasn't there before, we need to check if an entry didn't exist there previously and remember that so that
         // we can appropriately notify our clients of the addition of a new endpoint.
         //
         endpointIsNew = true;
     }

     if (apData)
     {
         size_t elementSize = 0;
         ReturnErrorOnFailure(GetElementTLVSize(apData, elementSize));
         Platform::ScopedMemoryBufferWithSize<uint8_t> backingBuffer;
         backingBuffer.Calloc(elementSize);
         VerifyOrReturnError(backingBuffer.Get() != nullptr, CHIP_ERROR_NO_MEMORY);
         TLV::ScopedBufferTLVWriter writer(std::move(backingBuffer), elementSize);
         ReturnErrorOnFailure(writer.CopyElement(TLV::AnonymousTag(), *apData));
         ReturnErrorOnFailure(writer.Finalize(backingBuffer));

         state.Set<Platform::ScopedMemoryBufferWithSize<uint8_t>>(std::move(backingBuffer));
         //
         // Clear out the committed data version and only set it again once we have received all data for this cluster.
         // Otherwise, we may have incomplete data that looks like it's complete since it has a valid data version.
         //
         mCache[aPath.mEndpointId][aPath.mClusterId].mCommittedDataVersion.ClearValue();

         // This commits a pending data version if the last report path is valid and it is different from the current path.
         if (mLastReportDataPath.IsValidConcreteClusterPath() && mLastReportDataPath != aPath)
         {
             CommitPendingDataVersion();
         }

         bool foundEncompassingWildcardPath = false;
         for (const auto & path : mRequestPathSet)
         {
             if (path.IncludesAllAttributesInCluster(aPath))
             {
                 foundEncompassingWildcardPath = true;
                 break;
             }
         }

         // if this data item is encompassed by a wildcard path, let's go ahead and update its pending data version.
         if (foundEncompassingWildcardPath)
         {
             mCache[aPath.mEndpointId][aPath.mClusterId].mPendingDataVersion = aPath.mDataVersion;
         }

         mLastReportDataPath = aPath;
     }
     else
     {
         state.Set<StatusIB>(aStatus);
     }

     //
     // if the endpoint didn't exist previously, let's track the insertion
     // so that we can inform our callback of a new endpoint being added appropriately.
     //
     if (endpointIsNew)
     {
         mAddedEndpoints.push_back(aPath.mEndpointId);
     }

     mCache[aPath.mEndpointId][aPath.mClusterId].mAttributes[aPath.mAttributeId] = std::move(state);
     mChangedAttributeSet.insert(aPath);
     return CHIP_NO_ERROR;
 }

 CHIP_ERROR ClusterStateCache::UpdateEventCache(const EventHeader & aEventHeader, TLV::TLVReader * apData, const StatusIB * apStatus)
 {
     if (apData)
     {
         //
         // If we've already seen this event before, there's no more work to be done.
         //
         if (mHighestReceivedEventNumber.HasValue() && aEventHeader.mEventNumber <= mHighestReceivedEventNumber.Value())
         {
             return CHIP_NO_ERROR;
         }
         System::PacketBufferHandle handle = System::PacketBufferHandle::New(chip::app::kMaxSecureSduLengthBytes);
         VerifyOrReturnError(!handle.IsNull(), CHIP_ERROR_NO_MEMORY);

         System::PacketBufferTLVWriter writer;
         writer.Init(std::move(handle), false);

         ReturnErrorOnFailure(writer.CopyElement(TLV::AnonymousTag(), *apData));
         ReturnErrorOnFailure(writer.Finalize(&handle));

         //
         // Compact the buffer down to a more reasonably sized packet buffer
         // if we can.
         //
         handle.RightSize();

         EventData eventData;
         eventData.first  = aEventHeader;
         eventData.second = std::move(handle);

         mEventDataCache.insert(std::move(eventData));

         mHighestReceivedEventNumber.SetValue(aEventHeader.mEventNumber);
     }
     else if (apStatus)
     {
         mEventStatusCache[aEventHeader.mPath] = *apStatus;
     }

     return CHIP_NO_ERROR;
 }

 void ClusterStateCache::OnReportBegin()
 {
     mLastReportDataPath = ConcreteClusterPath(kInvalidEndpointId, kInvalidClusterId);
     mChangedAttributeSet.clear();
     mAddedEndpoints.clear();
     mCallback.OnReportBegin();
 }

 void ClusterStateCache::CommitPendingDataVersion()
 {
     if (!mLastReportDataPath.IsValidConcreteClusterPath())
     {
         return;
     }

     auto & lastClusterInfo = mCache[mLastReportDataPath.mEndpointId][mLastReportDataPath.mClusterId];
     if (lastClusterInfo.mPendingDataVersion.HasValue())
     {
         lastClusterInfo.mCommittedDataVersion = lastClusterInfo.mPendingDataVersion;
         lastClusterInfo.mPendingDataVersion.ClearValue();
     }
 }

 void ClusterStateCache::OnReportEnd()
 {
     CommitPendingDataVersion();
     mLastReportDataPath = ConcreteClusterPath(kInvalidEndpointId, kInvalidClusterId);
     std::set<std::tuple<EndpointId, ClusterId>> changedClusters;

     //
     // Add the EndpointId and ClusterId into a set so that we only
     // convey unique combinations in the subsequent OnClusterChanged callback.
     //
     for (auto & path : mChangedAttributeSet)
     {
         mCallback.OnAttributeChanged(this, path);
         changedClusters.insert(std::make_tuple(path.mEndpointId, path.mClusterId));
     }

     for (auto & item : changedClusters)
     {
         mCallback.OnClusterChanged(this, std::get<0>(item), std::get<1>(item));
     }

     for (auto endpoint : mAddedEndpoints)
     {
         mCallback.OnEndpointAdded(this, endpoint);
     }

     mCallback.OnReportEnd();
 }

 CHIP_ERROR ClusterStateCache::Get(const ConcreteAttributePath & path, TLV::TLVReader & reader) const
 {
     CHIP_ERROR err;
     auto attributeState = GetAttributeState(path.mEndpointId, path.mClusterId, path.mAttributeId, err);
     ReturnErrorOnFailure(err);
     if (attributeState->Is<StatusIB>())
     {
         return CHIP_ERROR_IM_STATUS_CODE_RECEIVED;
     }

     reader.Init(attributeState->Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().Get(),
                 attributeState->Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().AllocatedSize());
     return reader.Next();
 }

 CHIP_ERROR ClusterStateCache::Get(EventNumber eventNumber, TLV::TLVReader & reader) const
 {
     CHIP_ERROR err;

     auto eventData = GetEventData(eventNumber, err);
     ReturnErrorOnFailure(err);

     System::PacketBufferTLVReader bufReader;

     bufReader.Init(eventData->second.Retain());
     ReturnErrorOnFailure(bufReader.Next());

     reader.Init(bufReader);
     return CHIP_NO_ERROR;
 }

 const ClusterStateCache::EndpointState * ClusterStateCache::GetEndpointState(EndpointId endpointId, CHIP_ERROR & err) const
 {
     auto endpointIter = mCache.find(endpointId);
     if (endpointIter == mCache.end())
     {
         err = CHIP_ERROR_KEY_NOT_FOUND;
         return nullptr;
     }

     err = CHIP_NO_ERROR;
     return &endpointIter->second;
 }

 const ClusterStateCache::ClusterState * ClusterStateCache::GetClusterState(EndpointId endpointId, ClusterId clusterId,
                                                                            CHIP_ERROR & err) const
 {
     auto endpointState = GetEndpointState(endpointId, err);
     if (err != CHIP_NO_ERROR)
     {
         return nullptr;
     }

     auto clusterState = endpointState->find(clusterId);
     if (clusterState == endpointState->end())
     {
         err = CHIP_ERROR_KEY_NOT_FOUND;
         return nullptr;
     }

     err = CHIP_NO_ERROR;
     return &clusterState->second;
 }

 const ClusterStateCache::AttributeState * ClusterStateCache::GetAttributeState(EndpointId endpointId, ClusterId clusterId,
                                                                                AttributeId attributeId, CHIP_ERROR & err) const
 {
     auto clusterState = GetClusterState(endpointId, clusterId, err);
     if (err != CHIP_NO_ERROR)
     {
         return nullptr;
     }

     auto attributeState = clusterState->mAttributes.find(attributeId);
     if (attributeState == clusterState->mAttributes.end())
     {
         err = CHIP_ERROR_KEY_NOT_FOUND;
         return nullptr;
     }

     err = CHIP_NO_ERROR;
     return &attributeState->second;
 }

 const ClusterStateCache::EventData * ClusterStateCache::GetEventData(EventNumber eventNumber, CHIP_ERROR & err) const
 {
     EventData compareKey;

     compareKey.first.mEventNumber = eventNumber;
     auto eventData                = mEventDataCache.find(std::move(compareKey));
     if (eventData == mEventDataCache.end())
     {
         err = CHIP_ERROR_KEY_NOT_FOUND;
         return nullptr;
     }

     err = CHIP_NO_ERROR;
     return &(*eventData);
 }

 void ClusterStateCache::OnAttributeData(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apData, const StatusIB & aStatus)
 {
     //
     // Since the cache itself is a ReadClient::Callback, it may be incorrectly passed in directly when registering with the
     // ReadClient. This should be avoided, since that bypasses the built-in buffered reader adapter callback that is needed for
     // lists to work correctly.
     //
     // Instead, the right callback should be retrieved using GetBufferedCallback().
     //
     // To catch such errors, we validate that the provided concrete path never indicates a raw list item operation (which the
     // buffered reader will handle and convert for us).
     //
     //
     VerifyOrDie(!aPath.IsListItemOperation());

     // Copy the reader for forwarding
     TLV::TLVReader dataSnapshot;
     if (apData)
     {
         dataSnapshot.Init(*apData);
     }

     UpdateCache(aPath, apData, aStatus);

     //
     // Forward the call through.
     //
     mCallback.OnAttributeData(aPath, apData ? &dataSnapshot : nullptr, aStatus);
 }

 CHIP_ERROR ClusterStateCache::GetVersion(const ConcreteClusterPath & aPath, Optional<DataVersion> & aVersion) const
 {
     VerifyOrReturnError(aPath.IsValidConcreteClusterPath(), CHIP_ERROR_INVALID_ARGUMENT);
     CHIP_ERROR err;
     auto clusterState = GetClusterState(aPath.mEndpointId, aPath.mClusterId, err);
     ReturnErrorOnFailure(err);
     aVersion = clusterState->mCommittedDataVersion;
     return CHIP_NO_ERROR;
 }

 void ClusterStateCache::OnEventData(const EventHeader & aEventHeader, TLV::TLVReader * apData, const StatusIB * apStatus)
 {
     VerifyOrDie(apData != nullptr || apStatus != nullptr);

     TLV::TLVReader dataSnapshot;
     if (apData)
     {
         dataSnapshot.Init(*apData);
     }

     UpdateEventCache(aEventHeader, apData, apStatus);
     mCallback.OnEventData(aEventHeader, apData ? &dataSnapshot : nullptr, apStatus);
 }

 CHIP_ERROR ClusterStateCache::GetStatus(const ConcreteAttributePath & path, StatusIB & status) const
 {
     CHIP_ERROR err;

     auto attributeState = GetAttributeState(path.mEndpointId, path.mClusterId, path.mAttributeId, err);
     ReturnErrorOnFailure(err);

     if (!attributeState->Is<StatusIB>())
     {
         return CHIP_ERROR_INVALID_ARGUMENT;
     }

     status = attributeState->Get<StatusIB>();
     return CHIP_NO_ERROR;
 }

 CHIP_ERROR ClusterStateCache::GetStatus(const ConcreteEventPath & path, StatusIB & status) const
 {
     auto statusIter = mEventStatusCache.find(path);
     if (statusIter == mEventStatusCache.end())
     {
         return CHIP_ERROR_KEY_NOT_FOUND;
     }

     status = statusIter->second;
     return CHIP_NO_ERROR;
 }

 void ClusterStateCache::GetSortedFilters(std::vector<std::pair<DataVersionFilter, size_t>> & aVector) const
 {
     for (auto const & endpointIter : mCache)
     {
         EndpointId endpointId = endpointIter.first;
         for (auto const & clusterIter : endpointIter.second)
         {
             if (!clusterIter.second.mCommittedDataVersion.HasValue())
             {
                 continue;
             }
             DataVersion dataVersion = clusterIter.second.mCommittedDataVersion.Value();
             uint32_t clusterSize    = 0;
             ClusterId clusterId     = clusterIter.first;

             for (auto const & attributeIter : clusterIter.second.mAttributes)
             {
                 if (attributeIter.second.Is<StatusIB>())
                 {
                     clusterSize +=
                         5; // 1 byte: anonymous tag control byte for struct. 1 byte: control byte for uint8 value. 1 byte:
                            // context-specific tag for uint8 value.1 byte: the uint8 value. 1 byte: end of container.
                     if (attributeIter.second.Get<StatusIB>().mClusterStatus.HasValue())
                     {
                         clusterSize += 3; // 1 byte: control byte for uint8 value. 1 byte: context-specific tag for uint8 value. 1
                                           // byte: the uint8 value.
                     }
                 }
                 else
                 {
                     TLV::TLVReader bufReader;
                     bufReader.Init(attributeIter.second.Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().Get(),
                                    attributeIter.second.Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().AllocatedSize());
                     ReturnOnFailure(bufReader.Next());
                     // Skip to the end of the element.
                     ReturnOnFailure(bufReader.Skip());

                     // Compute the amount of value data
                     clusterSize += bufReader.GetLengthRead();
                 }
             }
             if (clusterSize == 0)
             {
                 continue;
             }

             DataVersionFilter filter(endpointId, clusterId, dataVersion);

             aVector.push_back(std::make_pair(filter, clusterSize));
         }
     }
     std::sort(aVector.begin(), aVector.end(),
               [](const std::pair<DataVersionFilter, size_t> & x, const std::pair<DataVersionFilter, size_t> & y) {
                   return x.second > y.second;
               });
 }

 CHIP_ERROR ClusterStateCache::OnUpdateDataVersionFilterList(DataVersionFilterIBs::Builder & aDataVersionFilterIBsBuilder,
                                                             const Span<AttributePathParams> & aAttributePaths,
                                                             bool & aEncodedDataVersionList)
 {
     CHIP_ERROR err = CHIP_NO_ERROR;
     TLV::TLVWriter backup;

     // Only put paths into mRequestPathSet if they cover clusters in their entirety and no other path in our path list
     // points to a specific attribute from any of those clusters.
     // this would help for data-out-of-sync issue when handling store data version for the particular case on two paths: (E1, C1,
     // wildcard), (wildcard, C1, A1)
     for (auto & attribute1 : aAttributePaths)
     {
         if (attribute1.HasWildcardAttributeId())
         {
             bool intersected = false;
             for (auto & attribute2 : aAttributePaths)
             {
                 if (attribute2.HasWildcardAttributeId())
                 {
                     continue;
                 }

                 if (attribute1.Intersects(attribute2))
                 {
                     intersected = true;
                     break;
                 }
             }

             if (!intersected)
             {
                 mRequestPathSet.insert(attribute1);
             }
         }
     }

     std::vector<std::pair<DataVersionFilter, size_t>> filterVector;
     GetSortedFilters(filterVector);

     aEncodedDataVersionList = false;
     for (auto & filter : filterVector)
     {
         bool intersected = false;
         aDataVersionFilterIBsBuilder.Checkpoint(backup);

         // if the particular cached cluster does not intersect with user provided attribute paths, skip the cached one
         for (const auto & attributePath : aAttributePaths)
         {
             if (attributePath.IncludesAttributesInCluster(filter.first))
             {
                 intersected = true;
                 break;
             }
         }
         if (!intersected)
         {
             continue;
         }

         DataVersionFilterIB::Builder & filterIB = aDataVersionFilterIBsBuilder.CreateDataVersionFilter();
         SuccessOrExit(err = aDataVersionFilterIBsBuilder.GetError());
         ClusterPathIB::Builder & filterPath = filterIB.CreatePath();
         SuccessOrExit(err = filterIB.GetError());
         SuccessOrExit(
             err = filterPath.Endpoint(filter.first.mEndpointId).Cluster(filter.first.mClusterId).EndOfClusterPathIB().GetError());
         SuccessOrExit(err = filterIB.DataVersion(filter.first.mDataVersion.Value()).EndOfDataVersionFilterIB().GetError());
         ChipLogProgress(DataManagement, "Update DataVersionFilter: Endpoint=%u Cluster=" ChipLogFormatMEI " Version=%" PRIu32,
                         filter.first.mEndpointId, ChipLogValueMEI(filter.first.mClusterId), filter.first.mDataVersion.Value());

         aEncodedDataVersionList = true;
     }

 exit:
     if (err == CHIP_ERROR_NO_MEMORY || err == CHIP_ERROR_BUFFER_TOO_SMALL)
     {
         ChipLogProgress(DataManagement, "OnUpdateDataVersionFilterList out of space; rolling back");
         aDataVersionFilterIBsBuilder.Rollback(backup);
         err = CHIP_NO_ERROR;
     }
     return err;
 }

 CHIP_ERROR ClusterStateCache::GetLastReportDataPath(ConcreteClusterPath & aPath)
 {
     if (mLastReportDataPath.IsValidConcreteClusterPath())
     {
         aPath = mLastReportDataPath;
         return CHIP_NO_ERROR;
     }
     return CHIP_ERROR_INCORRECT_STATE;
 }
 } // namespace app
 } // namespace chip
	/*
	*
	* Copyright (c) 2021 Project CHIP Authors
	* All rights reserved.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "system/SystemPacketBuffer.h"
	#include <app/ClusterStateCache.h>
	#include <app/InteractionModelEngine.h>
	#include <tuple>

	namespace chip {
	namespace app {

	CHIP_ERROR ClusterStateCache::GetElementTLVSize(TLV::TLVReader * apData, size_t & aSize)
	{
	Platform::ScopedMemoryBufferWithSize<uint8_t> backingBuffer;
	TLV::TLVReader reader;
	reader.Init(*apData);
	size_t totalBufSize = reader.GetTotalLength();
	backingBuffer.Calloc(totalBufSize);
	VerifyOrReturnError(backingBuffer.Get() != nullptr, CHIP_ERROR_NO_MEMORY);
	TLV::ScopedBufferTLVWriter writer(std::move(backingBuffer), totalBufSize);
	ReturnErrorOnFailure(writer.CopyElement(TLV::AnonymousTag(), reader));
	aSize = writer.GetLengthWritten();
	ReturnErrorOnFailure(writer.Finalize(backingBuffer));
	return CHIP_NO_ERROR;
	}

	CHIP_ERROR ClusterStateCache::UpdateCache(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apData,
	const StatusIB & aStatus)
	{
	AttributeState state;
	bool endpointIsNew = false;

	if (mCache.find(aPath.mEndpointId) == mCache.end())
	{
	//
	// Since we might potentially be creating a new entry at mCache[aPath.mEndpointId][aPath.mClusterId] that
	// wasn't there before, we need to check if an entry didn't exist there previously and remember that so that
	// we can appropriately notify our clients of the addition of a new endpoint.
	//
	endpointIsNew = true;
	}

	if (apData)
	{
	size_t elementSize = 0;
	ReturnErrorOnFailure(GetElementTLVSize(apData, elementSize));
	Platform::ScopedMemoryBufferWithSize<uint8_t> backingBuffer;
	backingBuffer.Calloc(elementSize);
	VerifyOrReturnError(backingBuffer.Get() != nullptr, CHIP_ERROR_NO_MEMORY);
	TLV::ScopedBufferTLVWriter writer(std::move(backingBuffer), elementSize);
	ReturnErrorOnFailure(writer.CopyElement(TLV::AnonymousTag(), *apData));
	ReturnErrorOnFailure(writer.Finalize(backingBuffer));

	state.Set<Platform::ScopedMemoryBufferWithSize<uint8_t>>(std::move(backingBuffer));
	//
	// Clear out the committed data version and only set it again once we have received all data for this cluster.
	// Otherwise, we may have incomplete data that looks like it's complete since it has a valid data version.
	//
	mCache[aPath.mEndpointId][aPath.mClusterId].mCommittedDataVersion.ClearValue();

	// This commits a pending data version if the last report path is valid and it is different from the current path.
	if (mLastReportDataPath.IsValidConcreteClusterPath() && mLastReportDataPath != aPath)
	{
	CommitPendingDataVersion();
	}

	bool foundEncompassingWildcardPath = false;
	for (const auto & path : mRequestPathSet)
	{
	if (path.IncludesAllAttributesInCluster(aPath))
	{
	foundEncompassingWildcardPath = true;
	break;
	}
	}

	// if this data item is encompassed by a wildcard path, let's go ahead and update its pending data version.
	if (foundEncompassingWildcardPath)
	{
	mCache[aPath.mEndpointId][aPath.mClusterId].mPendingDataVersion = aPath.mDataVersion;
	}

	mLastReportDataPath = aPath;
	}
	else
	{
	state.Set<StatusIB>(aStatus);
	}

	//
	// if the endpoint didn't exist previously, let's track the insertion
	// so that we can inform our callback of a new endpoint being added appropriately.
	//
	if (endpointIsNew)
	{
	mAddedEndpoints.push_back(aPath.mEndpointId);
	}

	mCache[aPath.mEndpointId][aPath.mClusterId].mAttributes[aPath.mAttributeId] = std::move(state);
	mChangedAttributeSet.insert(aPath);
	return CHIP_NO_ERROR;
	}

	CHIP_ERROR ClusterStateCache::UpdateEventCache(const EventHeader & aEventHeader, TLV::TLVReader * apData, const StatusIB * apStatus)
	{
	if (apData)
	{
	//
	// If we've already seen this event before, there's no more work to be done.
	//
	if (mHighestReceivedEventNumber.HasValue() && aEventHeader.mEventNumber <= mHighestReceivedEventNumber.Value())
	{
	return CHIP_NO_ERROR;
	}
	System::PacketBufferHandle handle = System::PacketBufferHandle::New(chip::app::kMaxSecureSduLengthBytes);
	VerifyOrReturnError(!handle.IsNull(), CHIP_ERROR_NO_MEMORY);

	System::PacketBufferTLVWriter writer;
	writer.Init(std::move(handle), false);

	ReturnErrorOnFailure(writer.CopyElement(TLV::AnonymousTag(), *apData));
	ReturnErrorOnFailure(writer.Finalize(&handle));

	//
	// Compact the buffer down to a more reasonably sized packet buffer
	// if we can.
	//
	handle.RightSize();

	EventData eventData;
	eventData.first = aEventHeader;
	eventData.second = std::move(handle);

	mEventDataCache.insert(std::move(eventData));

	mHighestReceivedEventNumber.SetValue(aEventHeader.mEventNumber);
	}
	else if (apStatus)
	{
	mEventStatusCache[aEventHeader.mPath] = *apStatus;
	}

	return CHIP_NO_ERROR;
	}

	void ClusterStateCache::OnReportBegin()
	{
	mLastReportDataPath = ConcreteClusterPath(kInvalidEndpointId, kInvalidClusterId);
	mChangedAttributeSet.clear();
	mAddedEndpoints.clear();
	mCallback.OnReportBegin();
	}

	void ClusterStateCache::CommitPendingDataVersion()
	{
	if (!mLastReportDataPath.IsValidConcreteClusterPath())
	{
	return;
	}

	auto & lastClusterInfo = mCache[mLastReportDataPath.mEndpointId][mLastReportDataPath.mClusterId];
	if (lastClusterInfo.mPendingDataVersion.HasValue())
	{
	lastClusterInfo.mCommittedDataVersion = lastClusterInfo.mPendingDataVersion;
	lastClusterInfo.mPendingDataVersion.ClearValue();
	}
	}

	void ClusterStateCache::OnReportEnd()
	{
	CommitPendingDataVersion();
	mLastReportDataPath = ConcreteClusterPath(kInvalidEndpointId, kInvalidClusterId);
	std::set<std::tuple<EndpointId, ClusterId>> changedClusters;

	//
	// Add the EndpointId and ClusterId into a set so that we only
	// convey unique combinations in the subsequent OnClusterChanged callback.
	//
	for (auto & path : mChangedAttributeSet)
	{
	mCallback.OnAttributeChanged(this, path);
	changedClusters.insert(std::make_tuple(path.mEndpointId, path.mClusterId));
	}

	for (auto & item : changedClusters)
	{
	mCallback.OnClusterChanged(this, std::get<0>(item), std::get<1>(item));
	}

	for (auto endpoint : mAddedEndpoints)
	{
	mCallback.OnEndpointAdded(this, endpoint);
	}

	mCallback.OnReportEnd();
	}

	CHIP_ERROR ClusterStateCache::Get(const ConcreteAttributePath & path, TLV::TLVReader & reader) const
	{
	CHIP_ERROR err;
	auto attributeState = GetAttributeState(path.mEndpointId, path.mClusterId, path.mAttributeId, err);
	ReturnErrorOnFailure(err);
	if (attributeState->Is<StatusIB>())
	{
	return CHIP_ERROR_IM_STATUS_CODE_RECEIVED;
	}

	reader.Init(attributeState->Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().Get(),
	attributeState->Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().AllocatedSize());
	return reader.Next();
	}

	CHIP_ERROR ClusterStateCache::Get(EventNumber eventNumber, TLV::TLVReader & reader) const
	{
	CHIP_ERROR err;

	auto eventData = GetEventData(eventNumber, err);
	ReturnErrorOnFailure(err);

	System::PacketBufferTLVReader bufReader;

	bufReader.Init(eventData->second.Retain());
	ReturnErrorOnFailure(bufReader.Next());

	reader.Init(bufReader);
	return CHIP_NO_ERROR;
	}

	const ClusterStateCache::EndpointState * ClusterStateCache::GetEndpointState(EndpointId endpointId, CHIP_ERROR & err) const
	{
	auto endpointIter = mCache.find(endpointId);
	if (endpointIter == mCache.end())
	{
	err = CHIP_ERROR_KEY_NOT_FOUND;
	return nullptr;
	}

	err = CHIP_NO_ERROR;
	return &endpointIter->second;
	}

	const ClusterStateCache::ClusterState * ClusterStateCache::GetClusterState(EndpointId endpointId, ClusterId clusterId,
	CHIP_ERROR & err) const
	{
	auto endpointState = GetEndpointState(endpointId, err);
	if (err != CHIP_NO_ERROR)
	{
	return nullptr;
	}

	auto clusterState = endpointState->find(clusterId);
	if (clusterState == endpointState->end())
	{
	err = CHIP_ERROR_KEY_NOT_FOUND;
	return nullptr;
	}

	err = CHIP_NO_ERROR;
	return &clusterState->second;
	}

	const ClusterStateCache::AttributeState * ClusterStateCache::GetAttributeState(EndpointId endpointId, ClusterId clusterId,
	AttributeId attributeId, CHIP_ERROR & err) const
	{
	auto clusterState = GetClusterState(endpointId, clusterId, err);
	if (err != CHIP_NO_ERROR)
	{
	return nullptr;
	}

	auto attributeState = clusterState->mAttributes.find(attributeId);
	if (attributeState == clusterState->mAttributes.end())
	{
	err = CHIP_ERROR_KEY_NOT_FOUND;
	return nullptr;
	}

	err = CHIP_NO_ERROR;
	return &attributeState->second;
	}

	const ClusterStateCache::EventData * ClusterStateCache::GetEventData(EventNumber eventNumber, CHIP_ERROR & err) const
	{
	EventData compareKey;

	compareKey.first.mEventNumber = eventNumber;
	auto eventData = mEventDataCache.find(std::move(compareKey));
	if (eventData == mEventDataCache.end())
	{
	err = CHIP_ERROR_KEY_NOT_FOUND;
	return nullptr;
	}

	err = CHIP_NO_ERROR;
	return &(*eventData);
	}

	void ClusterStateCache::OnAttributeData(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apData, const StatusIB & aStatus)
	{
	//
	// Since the cache itself is a ReadClient::Callback, it may be incorrectly passed in directly when registering with the
	// ReadClient. This should be avoided, since that bypasses the built-in buffered reader adapter callback that is needed for
	// lists to work correctly.
	//
	// Instead, the right callback should be retrieved using GetBufferedCallback().
	//
	// To catch such errors, we validate that the provided concrete path never indicates a raw list item operation (which the
	// buffered reader will handle and convert for us).
	//
	//
	VerifyOrDie(!aPath.IsListItemOperation());

	// Copy the reader for forwarding
	TLV::TLVReader dataSnapshot;
	if (apData)
	{
	dataSnapshot.Init(*apData);
	}

	UpdateCache(aPath, apData, aStatus);

	//
	// Forward the call through.
	//
	mCallback.OnAttributeData(aPath, apData ? &dataSnapshot : nullptr, aStatus);
	}

	CHIP_ERROR ClusterStateCache::GetVersion(const ConcreteClusterPath & aPath, Optional<DataVersion> & aVersion) const
	{
	VerifyOrReturnError(aPath.IsValidConcreteClusterPath(), CHIP_ERROR_INVALID_ARGUMENT);
	CHIP_ERROR err;
	auto clusterState = GetClusterState(aPath.mEndpointId, aPath.mClusterId, err);
	ReturnErrorOnFailure(err);
	aVersion = clusterState->mCommittedDataVersion;
	return CHIP_NO_ERROR;
	}

	void ClusterStateCache::OnEventData(const EventHeader & aEventHeader, TLV::TLVReader * apData, const StatusIB * apStatus)
	{
	VerifyOrDie(apData != nullptr \|\| apStatus != nullptr);

	TLV::TLVReader dataSnapshot;
	if (apData)
	{
	dataSnapshot.Init(*apData);
	}

	UpdateEventCache(aEventHeader, apData, apStatus);
	mCallback.OnEventData(aEventHeader, apData ? &dataSnapshot : nullptr, apStatus);
	}

	CHIP_ERROR ClusterStateCache::GetStatus(const ConcreteAttributePath & path, StatusIB & status) const
	{
	CHIP_ERROR err;

	auto attributeState = GetAttributeState(path.mEndpointId, path.mClusterId, path.mAttributeId, err);
	ReturnErrorOnFailure(err);

	if (!attributeState->Is<StatusIB>())
	{
	return CHIP_ERROR_INVALID_ARGUMENT;
	}

	status = attributeState->Get<StatusIB>();
	return CHIP_NO_ERROR;
	}

	CHIP_ERROR ClusterStateCache::GetStatus(const ConcreteEventPath & path, StatusIB & status) const
	{
	auto statusIter = mEventStatusCache.find(path);
	if (statusIter == mEventStatusCache.end())
	{
	return CHIP_ERROR_KEY_NOT_FOUND;
	}

	status = statusIter->second;
	return CHIP_NO_ERROR;
	}

	void ClusterStateCache::GetSortedFilters(std::vector<std::pair<DataVersionFilter, size_t>> & aVector) const
	{
	for (auto const & endpointIter : mCache)
	{
	EndpointId endpointId = endpointIter.first;
	for (auto const & clusterIter : endpointIter.second)
	{
	if (!clusterIter.second.mCommittedDataVersion.HasValue())
	{
	continue;
	}
	DataVersion dataVersion = clusterIter.second.mCommittedDataVersion.Value();
	uint32_t clusterSize = 0;
	ClusterId clusterId = clusterIter.first;

	for (auto const & attributeIter : clusterIter.second.mAttributes)
	{
	if (attributeIter.second.Is<StatusIB>())
	{
	clusterSize +=
	5; // 1 byte: anonymous tag control byte for struct. 1 byte: control byte for uint8 value. 1 byte:
	// context-specific tag for uint8 value.1 byte: the uint8 value. 1 byte: end of container.
	if (attributeIter.second.Get<StatusIB>().mClusterStatus.HasValue())
	{
	clusterSize += 3; // 1 byte: control byte for uint8 value. 1 byte: context-specific tag for uint8 value. 1
	// byte: the uint8 value.
	}
	}
	else
	{
	TLV::TLVReader bufReader;
	bufReader.Init(attributeIter.second.Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().Get(),
	attributeIter.second.Get<Platform::ScopedMemoryBufferWithSize<uint8_t>>().AllocatedSize());
	ReturnOnFailure(bufReader.Next());
	// Skip to the end of the element.
	ReturnOnFailure(bufReader.Skip());

	// Compute the amount of value data
	clusterSize += bufReader.GetLengthRead();
	}
	}
	if (clusterSize == 0)
	{
	continue;
	}

	DataVersionFilter filter(endpointId, clusterId, dataVersion);

	aVector.push_back(std::make_pair(filter, clusterSize));
	}
	}
	std::sort(aVector.begin(), aVector.end(),
	[](const std::pair<DataVersionFilter, size_t> & x, const std::pair<DataVersionFilter, size_t> & y) {
	return x.second > y.second;
	});
	}

	CHIP_ERROR ClusterStateCache::OnUpdateDataVersionFilterList(DataVersionFilterIBs::Builder & aDataVersionFilterIBsBuilder,
	const Span<AttributePathParams> & aAttributePaths,
	bool & aEncodedDataVersionList)
	{
	CHIP_ERROR err = CHIP_NO_ERROR;
	TLV::TLVWriter backup;

	// Only put paths into mRequestPathSet if they cover clusters in their entirety and no other path in our path list
	// points to a specific attribute from any of those clusters.
	// this would help for data-out-of-sync issue when handling store data version for the particular case on two paths: (E1, C1,
	// wildcard), (wildcard, C1, A1)
	for (auto & attribute1 : aAttributePaths)
	{
	if (attribute1.HasWildcardAttributeId())
	{
	bool intersected = false;
	for (auto & attribute2 : aAttributePaths)
	{
	if (attribute2.HasWildcardAttributeId())
	{
	continue;
	}

	if (attribute1.Intersects(attribute2))
	{
	intersected = true;
	break;
	}
	}

	if (!intersected)
	{
	mRequestPathSet.insert(attribute1);
	}
	}
	}

	std::vector<std::pair<DataVersionFilter, size_t>> filterVector;
	GetSortedFilters(filterVector);

	aEncodedDataVersionList = false;
	for (auto & filter : filterVector)
	{
	bool intersected = false;
	aDataVersionFilterIBsBuilder.Checkpoint(backup);

	// if the particular cached cluster does not intersect with user provided attribute paths, skip the cached one
	for (const auto & attributePath : aAttributePaths)
	{
	if (attributePath.IncludesAttributesInCluster(filter.first))
	{
	intersected = true;
	break;
	}
	}
	if (!intersected)
	{
	continue;
	}

	DataVersionFilterIB::Builder & filterIB = aDataVersionFilterIBsBuilder.CreateDataVersionFilter();
	SuccessOrExit(err = aDataVersionFilterIBsBuilder.GetError());
	ClusterPathIB::Builder & filterPath = filterIB.CreatePath();
	SuccessOrExit(err = filterIB.GetError());
	SuccessOrExit(
	err = filterPath.Endpoint(filter.first.mEndpointId).Cluster(filter.first.mClusterId).EndOfClusterPathIB().GetError());
	SuccessOrExit(err = filterIB.DataVersion(filter.first.mDataVersion.Value()).EndOfDataVersionFilterIB().GetError());
	ChipLogProgress(DataManagement, "Update DataVersionFilter: Endpoint=%u Cluster=" ChipLogFormatMEI " Version=%" PRIu32,
	filter.first.mEndpointId, ChipLogValueMEI(filter.first.mClusterId), filter.first.mDataVersion.Value());

	aEncodedDataVersionList = true;
	}

	exit:
	if (err == CHIP_ERROR_NO_MEMORY \|\| err == CHIP_ERROR_BUFFER_TOO_SMALL)
	{
	ChipLogProgress(DataManagement, "OnUpdateDataVersionFilterList out of space; rolling back");
	aDataVersionFilterIBsBuilder.Rollback(backup);
	err = CHIP_NO_ERROR;
	}
	return err;
	}

	CHIP_ERROR ClusterStateCache::GetLastReportDataPath(ConcreteClusterPath & aPath)
	{
	if (mLastReportDataPath.IsValidConcreteClusterPath())
	{
	aPath = mLastReportDataPath;
	return CHIP_NO_ERROR;
	}
	return CHIP_ERROR_INCORRECT_STATE;
	}
	} // namespace app
	} // namespace chip