package optimizers

import (
	"context"
	"testing"

	"github.com/stretchr/testify/mock"
	"github.com/stretchr/testify/suite"
	"google.golang.org/protobuf/proto"

	"github.com/milvus-io/milvus/internal/proto/internalpb"
	"github.com/milvus-io/milvus/internal/proto/planpb"
	"github.com/milvus-io/milvus/internal/proto/querypb"
	"github.com/milvus-io/milvus/pkg/common"
	"github.com/milvus-io/milvus/pkg/util/merr"
	"github.com/milvus-io/milvus/pkg/util/paramtable"
)

type QueryHookSuite struct {
	suite.Suite
	queryHook QueryHook
}

func (suite *QueryHookSuite) SetupTest() {
}

func (suite *QueryHookSuite) TearDownTest() {
	suite.queryHook = nil
}

func (suite *QueryHookSuite) TestOptimizeSearchParam() {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	paramtable.Init()
	paramtable.Get().Save(paramtable.Get().AutoIndexConfig.EnableOptimize.Key, "true")

	suite.Run("normal_run", func() {
		paramtable.Get().Save(paramtable.Get().AutoIndexConfig.Enable.Key, "true")
		mockHook := NewMockQueryHook(suite.T())
		mockHook.EXPECT().Run(mock.Anything).Run(func(params map[string]any) {
			params[common.TopKKey] = int64(50)
			params[common.SearchParamKey] = `{"param": 2}`
		}).Return(nil)
		suite.queryHook = mockHook
		defer func() {
			paramtable.Get().Reset(paramtable.Get().AutoIndexConfig.Enable.Key)
			suite.queryHook = nil
		}()

		plan := &planpb.PlanNode{
			Node: &planpb.PlanNode_VectorAnns{
				VectorAnns: &planpb.VectorANNS{
					QueryInfo: &planpb.QueryInfo{
						Topk:         100,
						SearchParams: `{"param": 1}`,
					},
				},
			},
		}
		bs, err := proto.Marshal(plan)
		suite.Require().NoError(err)

		req, err := OptimizeSearchParams(ctx, &querypb.SearchRequest{
			Req: &internalpb.SearchRequest{
				SerializedExprPlan: bs,
			},
			TotalChannelNum: 2,
		}, suite.queryHook, 2)
		suite.NoError(err)
		suite.verifyQueryInfo(req, 50, `{"param": 2}`)
	})

	suite.Run("disable optimization", func() {
		mockHook := NewMockQueryHook(suite.T())
		suite.queryHook = mockHook
		defer func() { suite.queryHook = nil }()

		plan := &planpb.PlanNode{
			Node: &planpb.PlanNode_VectorAnns{
				VectorAnns: &planpb.VectorANNS{
					QueryInfo: &planpb.QueryInfo{
						Topk:         100,
						SearchParams: `{"param": 1}`,
					},
				},
			},
		}
		bs, err := proto.Marshal(plan)
		suite.Require().NoError(err)

		req, err := OptimizeSearchParams(ctx, &querypb.SearchRequest{
			Req: &internalpb.SearchRequest{
				SerializedExprPlan: bs,
			},
			TotalChannelNum: 2,
		}, suite.queryHook, 2)
		suite.NoError(err)
		suite.verifyQueryInfo(req, 100, `{"param": 1}`)
	})

	suite.Run("no_hook", func() {
		paramtable.Get().Save(paramtable.Get().AutoIndexConfig.Enable.Key, "true")
		defer paramtable.Get().Reset(paramtable.Get().AutoIndexConfig.Enable.Key)
		suite.queryHook = nil
		plan := &planpb.PlanNode{
			Node: &planpb.PlanNode_VectorAnns{
				VectorAnns: &planpb.VectorANNS{
					QueryInfo: &planpb.QueryInfo{
						Topk:         100,
						SearchParams: `{"param": 1}`,
					},
				},
			},
		}
		bs, err := proto.Marshal(plan)
		suite.Require().NoError(err)

		req, err := OptimizeSearchParams(ctx, &querypb.SearchRequest{
			Req: &internalpb.SearchRequest{
				SerializedExprPlan: bs,
			},
			TotalChannelNum: 2,
		}, suite.queryHook, 2)
		suite.NoError(err)
		suite.verifyQueryInfo(req, 100, `{"param": 1}`)
	})

	suite.Run("other_plannode", func() {
		paramtable.Get().Save(paramtable.Get().AutoIndexConfig.Enable.Key, "true")
		mockHook := NewMockQueryHook(suite.T())
		mockHook.EXPECT().Run(mock.Anything).Run(func(params map[string]any) {
			params[common.TopKKey] = int64(50)
			params[common.SearchParamKey] = `{"param": 2}`
		}).Return(nil).Maybe()
		suite.queryHook = mockHook
		defer func() {
			paramtable.Get().Reset(paramtable.Get().AutoIndexConfig.Enable.Key)
			suite.queryHook = nil
		}()

		plan := &planpb.PlanNode{
			Node: &planpb.PlanNode_Query{},
		}
		bs, err := proto.Marshal(plan)
		suite.Require().NoError(err)

		req, err := OptimizeSearchParams(ctx, &querypb.SearchRequest{
			Req: &internalpb.SearchRequest{
				SerializedExprPlan: bs,
			},
			TotalChannelNum: 2,
		}, suite.queryHook, 2)
		suite.NoError(err)
		suite.Equal(bs, req.GetReq().GetSerializedExprPlan())
	})

	suite.Run("no_serialized_plan", func() {
		paramtable.Get().Save(paramtable.Get().AutoIndexConfig.Enable.Key, "true")
		defer paramtable.Get().Reset(paramtable.Get().AutoIndexConfig.Enable.Key)
		mockHook := NewMockQueryHook(suite.T())
		suite.queryHook = mockHook
		defer func() { suite.queryHook = nil }()

		_, err := OptimizeSearchParams(ctx, &querypb.SearchRequest{
			Req:             &internalpb.SearchRequest{},
			TotalChannelNum: 2,
		}, suite.queryHook, 2)
		suite.Error(err)
	})

	suite.Run("hook_run_error", func() {
		paramtable.Get().Save(paramtable.Get().AutoIndexConfig.Enable.Key, "true")
		mockHook := NewMockQueryHook(suite.T())
		mockHook.EXPECT().Run(mock.Anything).Run(func(params map[string]any) {
			params[common.TopKKey] = int64(50)
			params[common.SearchParamKey] = `{"param": 2}`
		}).Return(merr.WrapErrServiceInternal("mocked"))
		suite.queryHook = mockHook
		defer func() {
			paramtable.Get().Reset(paramtable.Get().AutoIndexConfig.Enable.Key)
			suite.queryHook = nil
		}()

		plan := &planpb.PlanNode{
			Node: &planpb.PlanNode_VectorAnns{
				VectorAnns: &planpb.VectorANNS{
					QueryInfo: &planpb.QueryInfo{
						Topk:         100,
						SearchParams: `{"param": 1}`,
					},
				},
			},
		}
		bs, err := proto.Marshal(plan)
		suite.Require().NoError(err)

		_, err = OptimizeSearchParams(ctx, &querypb.SearchRequest{
			Req: &internalpb.SearchRequest{
				SerializedExprPlan: bs,
			},
		}, suite.queryHook, 2)
		suite.Error(err)
	})
}

func (suite *QueryHookSuite) verifyQueryInfo(req *querypb.SearchRequest, topK int64, param string) {
	planBytes := req.GetReq().GetSerializedExprPlan()

	plan := planpb.PlanNode{}
	err := proto.Unmarshal(planBytes, &plan)
	suite.Require().NoError(err)

	queryInfo := plan.GetVectorAnns().GetQueryInfo()
	suite.Equal(topK, queryInfo.GetTopk())
	suite.Equal(param, queryInfo.GetSearchParams())
}

func TestOptimizeSearchParam(t *testing.T) {
	suite.Run(t, new(QueryHookSuite))
}