// 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 datacoord

import (
	"context"
	"math/rand"
	"testing"
	"time"

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

	"github.com/milvus-io/milvus-proto/go-api/v2/commonpb"
	"github.com/milvus-io/milvus/internal/datacoord/allocator"
	"github.com/milvus-io/milvus/internal/datacoord/task"
	mocks2 "github.com/milvus-io/milvus/internal/metastore/mocks"
	"github.com/milvus-io/milvus/internal/metastore/model"
	"github.com/milvus-io/milvus/internal/mocks"
	"github.com/milvus-io/milvus/pkg/v2/proto/datapb"
	"github.com/milvus-io/milvus/pkg/v2/proto/workerpb"
	"github.com/milvus-io/milvus/pkg/v2/util/lock"
	"github.com/milvus-io/milvus/pkg/v2/util/typeutil"
)

func TestIndexInspector_inspect(t *testing.T) {
	t.Run("normal test", func(t *testing.T) {
		ctx := context.Background()
		notifyChan := make(chan int64, 1)
		scheduler := task.NewMockGlobalScheduler(t)
		alloc := allocator.NewMockAllocator(t)
		handler := NewNMockHandler(t)
		storage := mocks.NewChunkManager(t)
		versionManager := newIndexEngineVersionManager()
		catalog := mocks2.NewDataCoordCatalog(t)

		meta := &meta{
			segments:    NewSegmentsInfo(),
			collections: typeutil.NewConcurrentMap[UniqueID, *collectionInfo](),
			indexMeta: &indexMeta{
				keyLock:          lock.NewKeyLock[UniqueID](),
				catalog:          catalog,
				segmentBuildInfo: newSegmentIndexBuildInfo(),
				indexes:          make(map[UniqueID]map[UniqueID]*model.Index),
				segmentIndexes:   typeutil.NewConcurrentMap[UniqueID, *typeutil.ConcurrentMap[UniqueID, *model.SegmentIndex]](),
			},
		}

		segment := &SegmentInfo{
			SegmentInfo: &datapb.SegmentInfo{
				ID:           1,
				CollectionID: 2,
				PartitionID:  3,
				NumOfRows:    3000,
				State:        commonpb.SegmentState_Flushed,
				IsSorted:     true,
			},
		}
		meta.segments.SetSegment(segment.GetID(), segment)

		meta.indexMeta.indexes[2] = map[UniqueID]*model.Index{
			5: {
				CollectionID: 2,
				FieldID:      101,
				IndexID:      5,
				IndexName:    indexName,
			},
		}

		inspector := newIndexInspector(ctx, notifyChan, meta, scheduler, alloc, handler, storage, versionManager)

		inspector.Start()
		defer inspector.Stop()

		notifyChan <- segment.GetCollectionID()

		alloc.EXPECT().AllocID(mock.Anything).Return(rand.Int63(), nil)
		catalog.EXPECT().CreateSegmentIndex(mock.Anything, mock.Anything).Return(nil)
		catalog.EXPECT().AlterSegmentIndexes(mock.Anything, mock.Anything).Return(nil)
		scheduler.EXPECT().Enqueue(mock.Anything).Run(func(_a0 task.Task) {
			err := meta.indexMeta.AddSegmentIndex(context.TODO(), &model.SegmentIndex{
				SegmentID: segment.GetID(),
				BuildID:   segment.GetID(),
			})
			assert.NoError(t, err)
			err = meta.indexMeta.FinishTask(&workerpb.IndexTaskInfo{
				BuildID: segment.GetID(),
				State:   commonpb.IndexState_Finished,
			})
			assert.NoError(t, err)
		})

		assert.Eventually(t, func() bool {
			return !meta.indexMeta.IsUnIndexedSegment(segment.GetCollectionID(), segment.GetID())
		}, time.Second*10, time.Millisecond*10)
	})
}

func TestIndexInspector_ReloadFromMeta(t *testing.T) {
	ctx := context.Background()
	notifyChan := make(chan int64, 1)
	scheduler := task.NewMockGlobalScheduler(t)
	alloc := allocator.NewMockAllocator(t)
	handler := NewNMockHandler(t)
	storage := mocks.NewChunkManager(t)
	versionManager := newIndexEngineVersionManager()
	catalog := mocks2.NewDataCoordCatalog(t)

	meta := &meta{
		segments:    NewSegmentsInfo(),
		collections: typeutil.NewConcurrentMap[UniqueID, *collectionInfo](),
		indexMeta: &indexMeta{
			keyLock:          lock.NewKeyLock[UniqueID](),
			catalog:          catalog,
			segmentBuildInfo: newSegmentIndexBuildInfo(),
			indexes:          make(map[UniqueID]map[UniqueID]*model.Index),
			segmentIndexes:   typeutil.NewConcurrentMap[UniqueID, *typeutil.ConcurrentMap[UniqueID, *model.SegmentIndex]](),
		},
	}

	inspector := newIndexInspector(ctx, notifyChan, meta, scheduler, alloc, handler, storage, versionManager)

	catalog.EXPECT().CreateSegmentIndex(mock.Anything, mock.Anything).Return(nil)

	seg1 := &SegmentInfo{
		SegmentInfo: &datapb.SegmentInfo{
			ID:           1,
			CollectionID: 2,
			State:        commonpb.SegmentState_Flushed,
		},
	}
	meta.segments.SetSegment(seg1.ID, seg1)

	segIndex1 := &model.SegmentIndex{
		SegmentID:  seg1.ID,
		IndexID:    3,
		BuildID:    4,
		IndexState: commonpb.IndexState_Unissued,
	}
	meta.indexMeta.AddSegmentIndex(ctx, segIndex1)

	meta.indexMeta.indexes[2] = map[UniqueID]*model.Index{
		3: {
			CollectionID: 2,
			FieldID:      100,
			IndexID:      3,
			IndexName:    indexName,
		},
	}

	scheduler.EXPECT().Enqueue(mock.Anything).Return()
	inspector.reloadFromMeta()
}