// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you 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.

package querynode

import (
	"context"
	"errors"
	"math/rand"
	"runtime"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/mock"

	"github.com/milvus-io/milvus/internal/common"
	"github.com/milvus-io/milvus/internal/mq/msgstream"
	"github.com/milvus-io/milvus/internal/proto/commonpb"
	"github.com/milvus-io/milvus/internal/proto/internalpb"
	"github.com/milvus-io/milvus/internal/proto/querypb"
	"github.com/milvus-io/milvus/internal/proto/schemapb"
	"github.com/milvus-io/milvus/internal/storage"
	"github.com/milvus-io/milvus/internal/util/funcutil"
)

func TestSegmentLoader_loadSegment(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	schema := genTestCollectionSchema()
	fieldBinlog, statsLog, err := saveBinLog(ctx, defaultCollectionID, defaultPartitionID, defaultSegmentID, defaultMsgLength, schema)
	assert.NoError(t, err)

	t.Run("test load segment", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)

		node.metaReplica.removeSegment(defaultSegmentID, segmentTypeSealed)
		loader := node.loader
		assert.NotNil(t, loader)

		req := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    defaultSegmentID,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
					BinlogPaths:  fieldBinlog,
					Statslogs:    statsLog,
				},
			},
		}

		err = loader.loadSegment(req, segmentTypeSealed)
		assert.NoError(t, err)
	})

	t.Run("test set segment error due to without partition", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)

		err = node.metaReplica.removePartition(defaultPartitionID)
		assert.NoError(t, err)

		loader := node.loader
		assert.NotNil(t, loader)

		req := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    defaultSegmentID,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
					BinlogPaths:  fieldBinlog,
				},
			},
		}

		err = loader.loadSegment(req, segmentTypeSealed)
		assert.Error(t, err)
	})

	t.Run("test load segment with nil base message", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)

		loader := node.loader
		assert.NotNil(t, loader)

		req := &querypb.LoadSegmentsRequest{}

		err = loader.loadSegment(req, segmentTypeSealed)
		assert.Error(t, err)
	})
}

func TestSegmentLoader_loadSegmentFieldsData(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	runLoadSegmentFieldData := func(dataType schemapb.DataType, pkType schemapb.DataType) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)
		loader := node.loader
		assert.NotNil(t, loader)

		var fieldPk *schemapb.FieldSchema
		switch pkType {
		case schemapb.DataType_Int64:
			fieldPk = genPKFieldSchema(simpleInt64Field)
		case schemapb.DataType_VarChar:
			fieldPk = genPKFieldSchema(simpleVarCharField)
		default:
			panic("unsupported pk type")
		}
		schema := &schemapb.CollectionSchema{
			Name:   defaultCollectionName,
			AutoID: true,
			Fields: []*schemapb.FieldSchema{fieldPk},
		}

		switch dataType {
		case schemapb.DataType_Bool:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleBoolField))
		case schemapb.DataType_Int8:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleInt8Field))
		case schemapb.DataType_Int16:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleInt16Field))
		case schemapb.DataType_Int32:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleInt32Field))
		case schemapb.DataType_Int64:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleInt64Field))
		case schemapb.DataType_Float:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleFloatField))
		case schemapb.DataType_Double:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleDoubleField))
		case schemapb.DataType_VarChar:
			schema.Fields = append(schema.Fields, genConstantFieldSchema(simpleVarCharField))
		case schemapb.DataType_FloatVector:
			schema.Fields = append(schema.Fields, genVectorFieldSchema(simpleFloatVecField))
		case schemapb.DataType_BinaryVector:
			schema.Fields = append(schema.Fields, genVectorFieldSchema(simpleBinVecField))
		}

		loader.metaReplica.removeSegment(defaultSegmentID, segmentTypeSealed)

		col := newCollection(defaultCollectionID, schema)
		assert.NotNil(t, col)
		segment, err := newSegment(col,
			defaultSegmentID,
			defaultPartitionID,
			defaultCollectionID,
			defaultDMLChannel,
			segmentTypeSealed)
		assert.Nil(t, err)

		binlog, _, err := saveBinLog(ctx, defaultCollectionID, defaultPartitionID, defaultSegmentID, defaultMsgLength, schema)
		assert.NoError(t, err)

		err = loader.loadFiledBinlogData(segment, binlog)
		assert.NoError(t, err)
	}

	t.Run("int64 pk", func(t *testing.T) {
		runLoadSegmentFieldData(schemapb.DataType_Bool, schemapb.DataType_Int64)
		runLoadSegmentFieldData(schemapb.DataType_Int8, schemapb.DataType_Int64)
		runLoadSegmentFieldData(schemapb.DataType_Int16, schemapb.DataType_Int64)
		runLoadSegmentFieldData(schemapb.DataType_Int32, schemapb.DataType_Int64)
		runLoadSegmentFieldData(schemapb.DataType_Float, schemapb.DataType_Int64)
		runLoadSegmentFieldData(schemapb.DataType_Double, schemapb.DataType_Int64)
		//runLoadSegmentFieldData(schemapb.DataType_VarChar)
	})

	//t.Run("varChar pk", func(t *testing.T) {
	//	runLoadSegmentFieldData(schemapb.DataType_Bool, schemapb.DataType_VarChar)
	//	runLoadSegmentFieldData(schemapb.DataType_Int8, schemapb.DataType_VarChar)
	//	runLoadSegmentFieldData(schemapb.DataType_Int16, schemapb.DataType_VarChar)
	//	runLoadSegmentFieldData(schemapb.DataType_Int32, schemapb.DataType_VarChar)
	//	runLoadSegmentFieldData(schemapb.DataType_Int64, schemapb.DataType_VarChar)
	//	runLoadSegmentFieldData(schemapb.DataType_Float, schemapb.DataType_VarChar)
	//	runLoadSegmentFieldData(schemapb.DataType_Double, schemapb.DataType_VarChar)
	//})
}

func TestSegmentLoader_invalid(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	t.Run("test no collection", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)
		loader := node.loader
		assert.NotNil(t, loader)

		err = node.metaReplica.removeCollection(defaultCollectionID)
		assert.NoError(t, err)

		req := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    defaultSegmentID,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
				},
			},
		}

		err = loader.loadSegment(req, segmentTypeSealed)
		assert.Error(t, err)
	})

	t.Run("test no vec field 2", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)
		loader := node.loader
		assert.NotNil(t, loader)

		err = node.metaReplica.removeCollection(defaultCollectionID)
		assert.NoError(t, err)

		schema := &schemapb.CollectionSchema{
			Name:   defaultCollectionName,
			AutoID: true,
			Fields: []*schemapb.FieldSchema{
				genConstantFieldSchema(simpleInt8Field),
				genPKFieldSchema(simpleInt64Field),
			},
		}
		loader.metaReplica.addCollection(defaultCollectionID, schema)

		req := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    defaultSegmentID,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
				},
			},
		}
		err = loader.loadSegment(req, segmentTypeSealed)
		assert.Error(t, err)
	})

	t.Run("Test Invalid SegmentType", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)
		loader := node.loader
		assert.NotNil(t, loader)

		req := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    defaultSegmentID,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
				},
			},
		}

		err = loader.loadSegment(req, commonpb.SegmentState_Dropped)
		assert.Error(t, err)
	})
}

func TestSegmentLoader_checkSegmentSize(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	node, err := genSimpleQueryNode(ctx)
	assert.NoError(t, err)
	loader := node.loader
	assert.NotNil(t, loader)

	err = loader.checkSegmentSize(defaultCollectionID, []*querypb.SegmentLoadInfo{{SegmentID: defaultSegmentID, SegmentSize: 1024}}, runtime.GOMAXPROCS(0))
	assert.NoError(t, err)
}

func TestSegmentLoader_testLoadGrowing(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	t.Run("test load growing segments", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)
		loader := node.loader
		assert.NotNil(t, loader)

		collection, err := node.metaReplica.getCollectionByID(defaultCollectionID)
		assert.NoError(t, err)

		segment, err := newSegment(collection, defaultSegmentID+1, defaultPartitionID, defaultCollectionID, defaultDMLChannel, segmentTypeGrowing)
		assert.Nil(t, err)

		insertData, err := genInsertData(defaultMsgLength, collection.schema)
		assert.NoError(t, err)

		tsData, ok := insertData.Data[common.TimeStampField]
		assert.Equal(t, true, ok)
		utss := make([]uint64, tsData.RowNum())
		for i := 0; i < tsData.RowNum(); i++ {
			utss[i] = uint64(tsData.GetRow(i).(int64))
		}

		rowIDData, ok := insertData.Data[common.RowIDField]
		assert.Equal(t, true, ok)

		err = loader.loadGrowingSegments(segment, rowIDData.(*storage.Int64FieldData).Data, utss, insertData)
		assert.NoError(t, err)
	})

	t.Run("test invalid insert data", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)
		loader := node.loader
		assert.NotNil(t, loader)

		collection, err := node.metaReplica.getCollectionByID(defaultCollectionID)
		assert.NoError(t, err)

		segment, err := newSegment(collection, defaultSegmentID+1, defaultPartitionID, defaultCollectionID, defaultDMLChannel, segmentTypeGrowing)
		assert.Nil(t, err)

		insertData, err := genInsertData(defaultMsgLength, collection.schema)
		assert.NoError(t, err)

		tsData, ok := insertData.Data[common.TimeStampField]
		assert.Equal(t, true, ok)
		utss := make([]uint64, tsData.RowNum())
		for i := 0; i < tsData.RowNum(); i++ {
			utss[i] = uint64(tsData.GetRow(i).(int64))
		}

		rowIDData, ok := insertData.Data[common.RowIDField]
		assert.Equal(t, true, ok)

		err = loader.loadGrowingSegments(segment, rowIDData.(*storage.Int64FieldData).Data, utss, nil)
		assert.Error(t, err)
	})
}

func TestSegmentLoader_testLoadGrowingAndSealed(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	schema := genTestCollectionSchema()
	fieldBinlog, statsLog, err := saveBinLog(ctx, defaultCollectionID, defaultPartitionID, defaultSegmentID, defaultMsgLength, schema)
	assert.NoError(t, err)

	deltaLogs, err := saveDeltaLog(defaultCollectionID, defaultPartitionID, defaultSegmentID)
	assert.NoError(t, err)

	t.Run("test load sealed segments", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)

		loader := node.loader
		assert.NotNil(t, loader)

		segmentID1 := UniqueID(100)
		req1 := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    segmentID1,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
					BinlogPaths:  fieldBinlog,
					Statslogs:    statsLog,
				},
			},
		}

		err = loader.loadSegment(req1, segmentTypeSealed)
		assert.NoError(t, err)

		segment1, err := loader.metaReplica.getSegmentByID(segmentID1, segmentTypeSealed)
		assert.NoError(t, err)
		assert.Equal(t, segment1.getRowCount(), int64(100))

		segmentID2 := UniqueID(101)
		req2 := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    segmentID2,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
					BinlogPaths:  fieldBinlog,
					Deltalogs:    deltaLogs,
				},
			},
		}

		err = loader.loadSegment(req2, segmentTypeSealed)
		assert.NoError(t, err)

		segment2, err := loader.metaReplica.getSegmentByID(segmentID2, segmentTypeSealed)
		assert.NoError(t, err)
		// Note: getRowCount currently does not return accurate counts. The deleted rows are also counted.
		assert.Equal(t, segment2.getRowCount(), int64(100)) // accurate counts should be 98
	})

	t.Run("test load growing segments", func(t *testing.T) {
		node, err := genSimpleQueryNode(ctx)
		assert.NoError(t, err)

		loader := node.loader
		assert.NotNil(t, loader)

		segmentID1 := UniqueID(100)
		req1 := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    segmentID1,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
					BinlogPaths:  fieldBinlog,
				},
			},
		}

		err = loader.loadSegment(req1, segmentTypeGrowing)
		assert.NoError(t, err)

		segment1, err := loader.metaReplica.getSegmentByID(segmentID1, segmentTypeGrowing)
		assert.NoError(t, err)
		assert.Equal(t, segment1.getRowCount(), int64(100))

		segmentID2 := UniqueID(101)
		req2 := &querypb.LoadSegmentsRequest{
			Base: &commonpb.MsgBase{
				MsgType: commonpb.MsgType_WatchQueryChannels,
				MsgID:   rand.Int63(),
			},
			DstNodeID: 0,
			Schema:    schema,
			Infos: []*querypb.SegmentLoadInfo{
				{
					SegmentID:    segmentID2,
					PartitionID:  defaultPartitionID,
					CollectionID: defaultCollectionID,
					BinlogPaths:  fieldBinlog,
					Deltalogs:    deltaLogs,
				},
			},
		}

		err = loader.loadSegment(req2, segmentTypeGrowing)
		assert.NoError(t, err)

		segment2, err := loader.metaReplica.getSegmentByID(segmentID2, segmentTypeGrowing)
		assert.NoError(t, err)
		// Note: getRowCount currently does not return accurate counts. The deleted rows are also counted.
		assert.Equal(t, segment2.getRowCount(), int64(100)) // accurate counts should be 98
	})
}

func TestSegmentLoader_testLoadSealedSegmentWithIndex(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	schema := genTestCollectionSchema()

	// generate insert binlog
	fieldBinlog, statsLog, err := saveBinLog(ctx, defaultCollectionID, defaultPartitionID, defaultSegmentID, defaultMsgLength, schema)
	assert.NoError(t, err)

	segmentID := UniqueID(100)
	// generate index file for segment
	indexPaths, err := generateAndSaveIndex(segmentID, defaultMsgLength, IndexFaissIVFPQ, L2)
	assert.NoError(t, err)
	_, indexParams := genIndexParams(IndexFaissIVFPQ, L2)
	indexInfo := &querypb.FieldIndexInfo{
		FieldID:        simpleFloatVecField.id,
		EnableIndex:    true,
		IndexName:      indexName,
		IndexID:        indexID,
		BuildID:        buildID,
		IndexParams:    funcutil.Map2KeyValuePair(indexParams),
		IndexFilePaths: indexPaths,
	}

	// generate segmentLoader
	node, err := genSimpleQueryNode(ctx)
	assert.NoError(t, err)
	loader := node.loader
	assert.NotNil(t, loader)

	req := &querypb.LoadSegmentsRequest{
		Base: &commonpb.MsgBase{
			MsgType: commonpb.MsgType_WatchQueryChannels,
			MsgID:   rand.Int63(),
		},
		DstNodeID: 0,
		Schema:    schema,
		Infos: []*querypb.SegmentLoadInfo{
			{
				SegmentID:    segmentID,
				PartitionID:  defaultPartitionID,
				CollectionID: defaultCollectionID,
				BinlogPaths:  fieldBinlog,
				IndexInfos:   []*querypb.FieldIndexInfo{indexInfo},
				Statslogs:    statsLog,
			},
		},
	}

	err = loader.loadSegment(req, segmentTypeSealed)
	assert.NoError(t, err)

	segment, err := node.metaReplica.getSegmentByID(segmentID, segmentTypeSealed)
	assert.NoError(t, err)
	vecFieldInfo, err := segment.getIndexedFieldInfo(simpleFloatVecField.id)
	assert.NoError(t, err)
	assert.NotNil(t, vecFieldInfo)
	assert.Equal(t, true, vecFieldInfo.indexInfo.EnableIndex)
}

func TestSegmentLoader_testFromDmlCPLoadDelete(t *testing.T) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	position := &msgstream.MsgPosition{ChannelName: defaultDeltaChannel, MsgID: []byte{1}}

	// test for seek failed
	{
		mockMsg := &mockMsgID{}
		mockMsg.On("AtEarliestPosition").Return(false, nil)
		testSeekFailWhenConsumingDeltaMsg(ctx, t, position, mockMsg)
	}

	//test no more data when get last msg successfully
	{
		mockMsg := &mockMsgID{}
		mockMsg.On("AtEarliestPosition").Return(true, nil)
		assert.Nil(t, testConsumingDeltaMsg(ctx, t, position, true, mockMsg))
	}

	//test consume after seeking when get last msg successfully
	{
		mockMsg := &mockMsgID{}
		mockMsg.On("AtEarliestPosition").Return(false, nil)
		mockMsg.On("LessOrEqualThan", mock.AnythingOfType("string")).Return(true, nil)
		assert.Nil(t, testConsumingDeltaMsg(ctx, t, position, true, mockMsg))
	}

	//test compare msgID failed when get last msg successfully
	{
		mockMsg := &mockMsgID{}
		mockMsg.On("AtEarliestPosition").Return(false, nil)
		mockMsg.On("LessOrEqualThan", mock.AnythingOfType("string")).Return(true, errors.New(""))
		assert.NotNil(t, testConsumingDeltaMsg(ctx, t, position, true, mockMsg))
	}

	//test consume after seeking when get last msg failed
	{
		mockMsg := &mockMsgID{}
		mockMsg.On("AtEarliestPosition").Return(false, nil)
		mockMsg.On("LessOrEqualThan", mock.AnythingOfType("string")).Return(true, errors.New(""))
		assert.NotNil(t, testConsumingDeltaMsg(ctx, t, position, false, mockMsg))
	}
}

func testSeekFailWhenConsumingDeltaMsg(ctx context.Context, t *testing.T, position *msgstream.MsgPosition, mockMsg *mockMsgID) {
	msgStream := &LoadDeleteMsgStream{}
	errMsg := "seek failed"
	err := errors.New(errMsg)
	msgStream.On("AsConsumer", mock.AnythingOfTypeArgument("string"), mock.AnythingOfTypeArgument("string"))
	msgStream.On("Seek", mock.AnythingOfType("string")).Return(err)
	msgStream.On("GetLatestMsgID", mock.AnythingOfType("string")).Return(mockMsg, nil)

	factory := &mockMsgStreamFactory{mockMqStream: msgStream}
	node, err := genSimpleQueryNodeWithMQFactory(ctx, factory)
	assert.NoError(t, err)
	loader := node.loader
	assert.NotNil(t, loader)

	ret := loader.FromDmlCPLoadDelete(ctx, defaultCollectionID, position)
	assert.EqualError(t, ret, errMsg)
}

func testConsumingDeltaMsg(ctx context.Context, t *testing.T, position *msgstream.MsgPosition, getLastSucc bool, mockMsg *mockMsgID) error {
	msgStream := &LoadDeleteMsgStream{}
	msgStream.On("AsConsumer", mock.AnythingOfTypeArgument("string"), mock.AnythingOfTypeArgument("string"))
	msgStream.On("Seek", mock.AnythingOfType("string")).Return(nil)

	if getLastSucc {
		msgStream.On("GetLatestMsgID", mock.AnythingOfType("string")).Return(mockMsg, nil)
	} else {
		msgStream.On("GetLatestMsgID", mock.AnythingOfType("string")).Return(mockMsg, errors.New(""))
	}

	msgChan := make(chan *msgstream.MsgPack)
	go func() {
		msgChan <- nil
		deleteMsg1 := genDeleteMsg(defaultCollectionID+1, schemapb.DataType_Int64, defaultDelLength)
		deleteMsg2 := genDeleteMsg(defaultCollectionID, schemapb.DataType_Int64, defaultDelLength)
		msgChan <- &msgstream.MsgPack{Msgs: []msgstream.TsMsg{deleteMsg1, deleteMsg2}}
	}()

	msgStream.On("Chan").Return(msgChan)
	factory := &mockMsgStreamFactory{mockMqStream: msgStream}
	node, err := genSimpleQueryNodeWithMQFactory(ctx, factory)
	assert.NoError(t, err)

	loader := node.loader
	assert.NotNil(t, loader)

	return loader.FromDmlCPLoadDelete(ctx, defaultCollectionID, position)
}

type mockMsgID struct {
	msgstream.MessageID
	mock.Mock
}

func (m2 *mockMsgID) AtEarliestPosition() bool {
	args := m2.Called()
	return args.Get(0).(bool)
}

func (m2 *mockMsgID) LessOrEqualThan(msgID []byte) (bool, error) {
	args := m2.Called()
	ret := args.Get(0)
	if args.Get(1) != nil {
		return false, args.Get(1).(error)
	}
	return ret.(bool), nil
}

type LoadDeleteMsgStream struct {
	msgstream.MsgStream
	mock.Mock
}

func (ms *LoadDeleteMsgStream) Close() {
}

func (ms *LoadDeleteMsgStream) AsConsumer(channels []string, subName string) {
}

func (ms *LoadDeleteMsgStream) Chan() <-chan *msgstream.MsgPack {
	args := ms.Called()
	return args.Get(0).(chan *msgstream.MsgPack)
}

func (ms *LoadDeleteMsgStream) Seek(offset []*internalpb.MsgPosition) error {
	args := ms.Called()
	if args.Get(0) == nil {
		return nil
	}
	return args.Get(0).(error)
}

func (ms *LoadDeleteMsgStream) GetLatestMsgID(channel string) (msgstream.MessageID, error) {
	args := ms.Called(channel)
	msg := args.Get(0)
	err := args.Get(1)
	if msg == nil && err == nil {
		return nil, nil
	}

	if msg == nil && err != nil {
		return nil, err.(error)
	}

	if msg != nil && err == nil {
		return msg.(msgstream.MessageID), nil
	}

	return msg.(msgstream.MessageID), err.(error)
}

func (ms *LoadDeleteMsgStream) Start() {}

type getCollectionByIDFunc func(collectionID UniqueID) (*Collection, error)

type mockReplicaInterface struct {
	ReplicaInterface
	getCollectionByIDFunc
}

func (m *mockReplicaInterface) getCollectionByID(collectionID UniqueID) (*Collection, error) {
	if m.getCollectionByIDFunc != nil {
		return m.getCollectionByIDFunc(collectionID)
	}
	return nil, errors.New("mock")
}

func newMockReplicaInterface() *mockReplicaInterface {
	return &mockReplicaInterface{}
}

func TestSegmentLoader_getFieldType_err(t *testing.T) {
	replica, err := genSimpleReplica()
	assert.NoError(t, err)
	loader := &segmentLoader{metaReplica: replica}
	segment := &Segment{collectionID: 200}
	_, err = loader.getFieldType(segment, 100)
	assert.Error(t, err)
}

func TestSegmentLoader_getFieldType(t *testing.T) {
	replica := newMockReplicaInterface()
	loader := &segmentLoader{metaReplica: replica}

	// failed to get collection.
	segment := &Segment{segmentType: segmentTypeSealed}
	_, err := loader.getFieldType(segment, 100)
	assert.Error(t, err)

	segment.segmentType = segmentTypeGrowing
	_, err = loader.getFieldType(segment, 100)
	assert.Error(t, err)

	// normal case.
	replica.getCollectionByIDFunc = func(collectionID UniqueID) (*Collection, error) {
		return &Collection{
			schema: &schemapb.CollectionSchema{
				Fields: []*schemapb.FieldSchema{
					{
						Name:     "test",
						FieldID:  100,
						DataType: schemapb.DataType_Int64,
					},
				},
			},
		}, nil
	}

	segment.segmentType = segmentTypeGrowing
	fieldType, err := loader.getFieldType(segment, 100)
	assert.NoError(t, err)
	assert.Equal(t, schemapb.DataType_Int64, fieldType)

	segment.segmentType = segmentTypeSealed
	fieldType, err = loader.getFieldType(segment, 100)
	assert.NoError(t, err)
	assert.Equal(t, schemapb.DataType_Int64, fieldType)
}