// 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 observers

import (
	"context"
	"testing"
	"time"

	"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/querycoordv2/meta"
	. "github.com/milvus-io/milvus/internal/querycoordv2/params"
	"github.com/milvus-io/milvus/internal/querycoordv2/utils"
	"github.com/milvus-io/milvus/internal/util/etcd"
)

type TargetObserverSuite struct {
	suite.Suite

	kv *etcdkv.EtcdKV
	//dependency
	meta      *meta.Meta
	targetMgr *meta.TargetManager
	distMgr   *meta.DistributionManager
	broker    *meta.MockBroker

	observer *TargetObserver

	collectionID       int64
	partitionID        int64
	nextTargetSegments []*datapb.SegmentBinlogs
	nextTargetChannels []*datapb.VchannelInfo
}

func (suite *TargetObserverSuite) SetupSuite() {
	Params.Init()
	Params.QueryCoordCfg.UpdateNextTargetInterval = 3 * time.Second
}

func (suite *TargetObserverSuite) SetupTest() {
	var err error
	config := GenerateEtcdConfig()
	cli, err := etcd.GetEtcdClient(&config)
	suite.Require().NoError(err)
	suite.kv = etcdkv.NewEtcdKV(cli, config.MetaRootPath)

	// meta
	store := meta.NewMetaStore(suite.kv)
	idAllocator := RandomIncrementIDAllocator()
	suite.meta = meta.NewMeta(idAllocator, store)

	suite.broker = meta.NewMockBroker(suite.T())
	suite.targetMgr = meta.NewTargetManager(suite.broker, suite.meta)
	suite.distMgr = meta.NewDistributionManager()
	suite.observer = NewTargetObserver(suite.meta, suite.targetMgr, suite.distMgr, suite.broker)

	suite.observer.Start(context.TODO())

	suite.collectionID = int64(1000)
	suite.partitionID = int64(100)

	err = suite.meta.CollectionManager.PutCollection(utils.CreateTestCollection(suite.collectionID, 1))
	suite.NoError(err)
	err = suite.meta.CollectionManager.PutPartition(utils.CreateTestPartition(suite.collectionID, suite.partitionID))
	suite.NoError(err)

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

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

	suite.broker.EXPECT().GetRecoveryInfo(mock.Anything, mock.Anything, mock.Anything).Return(suite.nextTargetChannels, suite.nextTargetSegments, nil)
	suite.broker.EXPECT().GetPartitions(mock.Anything, mock.Anything).Return([]int64{suite.partitionID}, nil)
}

func (suite *TargetObserverSuite) TestTriggerUpdateTarget() {
	suite.Eventually(func() bool {
		return len(suite.targetMgr.GetHistoricalSegmentsByCollection(suite.collectionID, meta.NextTarget)) == 2
	}, 5*time.Second, 1*time.Second)

	suite.Eventually(func() bool {
		return len(suite.targetMgr.GetDmChannelsByCollection(suite.collectionID, meta.NextTarget)) == 2
	}, 5*time.Second, 1*time.Second)

	suite.distMgr.SegmentDistManager.Update(2, utils.CreateTestSegment(suite.collectionID, suite.partitionID, 11, 2, 0, "channel-1"))
	suite.distMgr.SegmentDistManager.Update(2, utils.CreateTestSegment(suite.collectionID, suite.partitionID, 12, 2, 1, "channel-2"))
	suite.distMgr.ChannelDistManager.Update(2, utils.CreateTestChannel(suite.collectionID, 2, 0, "channel-1"))
	suite.distMgr.ChannelDistManager.Update(2, utils.CreateTestChannel(suite.collectionID, 2, 1, "channel-2"))

	suite.Eventually(func() bool {
		return len(suite.targetMgr.GetHistoricalSegmentsByCollection(suite.collectionID, meta.CurrentTarget)) == 2
	}, 5*time.Second, 1*time.Second)

	suite.Eventually(func() bool {
		return len(suite.targetMgr.GetDmChannelsByCollection(suite.collectionID, meta.CurrentTarget)) == 2
	}, 5*time.Second, 1*time.Second)
}

func (suite *TargetObserverSuite) TearDownSuite() {
	suite.kv.Close()
	suite.observer.Stop()
}

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