// 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 meta

import (
	"testing"

	"github.com/samber/lo"
	"github.com/stretchr/testify/mock"
	"github.com/stretchr/testify/suite"

	etcdkv "github.com/milvus-io/milvus/internal/kv/etcd"
	"github.com/milvus-io/milvus/internal/proto/datapb"
	"github.com/milvus-io/milvus/internal/proto/querypb"
	. "github.com/milvus-io/milvus/internal/querycoordv2/params"
	"github.com/milvus-io/milvus/internal/querycoordv2/session"
	"github.com/milvus-io/milvus/internal/util/etcd"
	"github.com/milvus-io/milvus/internal/util/typeutil"
)

type TargetManagerSuite struct {
	suite.Suite

	// Data
	collections []int64
	partitions  map[int64][]int64
	channels    map[int64][]string
	segments    map[int64]map[int64][]int64 // CollectionID, PartitionID -> Segments
	// Derived data
	allChannels []string
	allSegments []int64

	kv     *etcdkv.EtcdKV
	meta   *Meta
	broker *MockBroker
	// Test object
	mgr *TargetManager
}

func (suite *TargetManagerSuite) SetupSuite() {
	Params.Init()
	suite.collections = []int64{1000, 1001}
	suite.partitions = map[int64][]int64{
		1000: {100, 101},
		1001: {102, 103},
	}
	suite.channels = map[int64][]string{
		1000: {"1000-dmc0", "1000-dmc1"},
		1001: {"1001-dmc0", "1001-dmc1"},
	}
	suite.segments = map[int64]map[int64][]int64{
		1000: {
			100: {1, 2},
			101: {3, 4},
		},
		1001: {
			102: {5, 6},
			103: {7, 8},
		},
	}

	suite.allChannels = make([]string, 0)
	suite.allSegments = make([]int64, 0)
	for _, channels := range suite.channels {
		suite.allChannels = append(suite.allChannels, channels...)
	}
	for _, partitions := range suite.segments {
		for _, segments := range partitions {
			suite.allSegments = append(suite.allSegments, segments...)
		}
	}
}

func (suite *TargetManagerSuite) SetupTest() {
	var err error
	config := GenerateEtcdConfig()
	cli, err := etcd.GetEtcdClient(
		config.UseEmbedEtcd.GetAsBool(),
		config.EtcdUseSSL.GetAsBool(),
		config.Endpoints.GetAsStrings(),
		config.EtcdTLSCert.GetValue(),
		config.EtcdTLSKey.GetValue(),
		config.EtcdTLSCACert.GetValue(),
		config.EtcdTLSMinVersion.GetValue())
	suite.Require().NoError(err)
	suite.kv = etcdkv.NewEtcdKV(cli, config.MetaRootPath.GetValue())

	// meta
	store := NewMetaStore(suite.kv)
	idAllocator := RandomIncrementIDAllocator()
	suite.meta = NewMeta(idAllocator, store, session.NewNodeManager())
	suite.broker = NewMockBroker(suite.T())
	suite.mgr = NewTargetManager(suite.broker, suite.meta)

	for _, collection := range suite.collections {
		dmChannels := make([]*datapb.VchannelInfo, 0)
		for _, channel := range suite.channels[collection] {
			dmChannels = append(dmChannels, &datapb.VchannelInfo{
				CollectionID: collection,
				ChannelName:  channel,
			})
		}

		for partition, segments := range suite.segments[collection] {
			allSegments := make([]*datapb.SegmentBinlogs, 0)
			for _, segment := range segments {

				allSegments = append(allSegments, &datapb.SegmentBinlogs{
					SegmentID:     segment,
					InsertChannel: suite.channels[collection][0],
				})
			}
			suite.broker.EXPECT().GetRecoveryInfo(mock.Anything, collection, partition).Return(dmChannels, allSegments, nil)
		}
		suite.broker.EXPECT().GetPartitions(mock.Anything, collection).Return(suite.partitions[collection], nil)
		suite.mgr.UpdateCollectionNextTargetWithPartitions(collection, suite.partitions[collection]...)
	}
}

func (suite *TargetManagerSuite) TearDownSuite() {
	suite.kv.Close()
}

func (suite *TargetManagerSuite) TestUpdateCurrentTarget() {
	collectionID := int64(1000)
	suite.assertSegments(suite.getAllSegment(collectionID, suite.partitions[collectionID]),
		suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels(suite.channels[collectionID], suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))

	suite.mgr.UpdateCollectionCurrentTarget(collectionID)
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments(suite.getAllSegment(collectionID, suite.partitions[collectionID]),
		suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels(suite.channels[collectionID], suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))
}

func (suite *TargetManagerSuite) TestUpdateNextTarget() {
	collectionID := int64(1003)
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))

	suite.meta.PutCollection(&Collection{
		CollectionLoadInfo: &querypb.CollectionLoadInfo{
			CollectionID:  collectionID,
			ReplicaNumber: 1},
	})
	suite.meta.PutPartition(&Partition{
		PartitionLoadInfo: &querypb.PartitionLoadInfo{
			CollectionID: collectionID,
			PartitionID:  1,
		},
	})

	nextTargetChannels := []*datapb.VchannelInfo{
		{
			CollectionID: collectionID,
			ChannelName:  "channel-1",
		},
		{
			CollectionID: collectionID,
			ChannelName:  "channel-2",
		},
	}

	nextTargetSegments := []*datapb.SegmentBinlogs{
		{
			SegmentID:     11,
			InsertChannel: "channel-1",
		},
		{
			SegmentID:     12,
			InsertChannel: "channel-2",
		},
	}

	suite.broker.EXPECT().GetPartitions(mock.Anything, collectionID).Return([]int64{1}, nil)
	suite.broker.EXPECT().GetRecoveryInfo(mock.Anything, collectionID, int64(1)).Return(nextTargetChannels, nextTargetSegments, nil)
	suite.mgr.UpdateCollectionNextTargetWithPartitions(collectionID, int64(1))
	suite.assertSegments([]int64{11, 12}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels([]string{"channel-1", "channel-2"}, suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))
}

func (suite *TargetManagerSuite) TestRemovePartition() {
	collectionID := int64(1000)
	suite.assertSegments(suite.getAllSegment(collectionID, suite.partitions[collectionID]), suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels(suite.channels[collectionID], suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))

	suite.mgr.RemovePartition(collectionID, 100)
	suite.assertSegments([]int64{3, 4}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels(suite.channels[collectionID], suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))
}

func (suite *TargetManagerSuite) TestRemoveCollection() {
	collectionID := int64(1000)
	suite.assertSegments(suite.getAllSegment(collectionID, suite.partitions[collectionID]), suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels(suite.channels[collectionID], suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))

	suite.mgr.RemoveCollection(collectionID)
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))

	collectionID = int64(1001)
	suite.mgr.UpdateCollectionCurrentTarget(collectionID)
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments(suite.getAllSegment(collectionID, suite.partitions[collectionID]), suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels(suite.channels[collectionID], suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))

	suite.mgr.RemoveCollection(collectionID)
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, NextTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, NextTarget))
	suite.assertSegments([]int64{}, suite.mgr.GetHistoricalSegmentsByCollection(collectionID, CurrentTarget))
	suite.assertChannels([]string{}, suite.mgr.GetDmChannelsByCollection(collectionID, CurrentTarget))
}

func (suite *TargetManagerSuite) getAllSegment(collectionID int64, partitionIDs []int64) []int64 {
	allSegments := make([]int64, 0)
	for collection, partitions := range suite.segments {
		if collectionID == collection {
			for partition, segments := range partitions {
				if lo.Contains(partitionIDs, partition) {
					allSegments = append(allSegments, segments...)
				}
			}
		}
	}

	return allSegments
}

func (suite *TargetManagerSuite) assertChannels(expected []string, actual map[string]*DmChannel) bool {
	if !suite.Equal(len(expected), len(actual)) {
		return false
	}

	set := typeutil.NewSet(expected...)
	for _, channel := range actual {
		set.Remove(channel.ChannelName)
	}

	return suite.Len(set, 0)
}

func (suite *TargetManagerSuite) assertSegments(expected []int64, actual map[int64]*datapb.SegmentInfo) bool {
	if !suite.Equal(len(expected), len(actual)) {
		return false
	}

	set := typeutil.NewUniqueSet(expected...)
	for _, segment := range actual {
		set.Remove(segment.ID)
	}

	return suite.Len(set, 0)
}

func TestTargetManager(t *testing.T) {
	suite.Run(t, new(TargetManagerSuite))
}
