// 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 querynodev2

import (
	"math"
	"math/rand"
	"strconv"

	"github.com/golang/protobuf/proto"

	"github.com/milvus-io/milvus-proto/go-api/v2/commonpb"
	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
	"github.com/milvus-io/milvus/internal/proto/planpb"
	"github.com/milvus-io/milvus/pkg/common"
	"github.com/milvus-io/milvus/pkg/util/typeutil"
)

// ---------- unittest util functions ----------
// common definitions
const (
	metricTypeKey       = common.MetricTypeKey
	defaultTopK         = int64(10)
	defaultRoundDecimal = int64(6)
	defaultDim          = 128
	defaultNProb        = 10
	defaultEf           = 10
	defaultMetricType   = "L2"
	defaultNQ           = 10
)

const (
	// index type
	IndexFaissIDMap      = "FLAT"
	IndexFaissIVFFlat    = "IVF_FLAT"
	IndexFaissIVFPQ      = "IVF_PQ"
	IndexScaNN           = "SCANN"
	IndexFaissIVFSQ8     = "IVF_SQ8"
	IndexFaissBinIDMap   = "BIN_FLAT"
	IndexFaissBinIVFFlat = "BIN_IVF_FLAT"

	IndexHNSW = "HNSW"
)

// ---------- unittest util functions ----------
// functions of messages and requests
func genSearchPlan(dataType schemapb.DataType, fieldID int64, metricType string) *planpb.PlanNode {
	var vectorType planpb.VectorType
	switch dataType {
	case schemapb.DataType_FloatVector:
		vectorType = planpb.VectorType_FloatVector
	case schemapb.DataType_Float16Vector:
		vectorType = planpb.VectorType_Float16Vector
	case schemapb.DataType_BinaryVector:
		vectorType = planpb.VectorType_BinaryVector
	}

	return &planpb.PlanNode{
		Node: &planpb.PlanNode_VectorAnns{
			VectorAnns: &planpb.VectorANNS{
				VectorType: vectorType,
				FieldId:    fieldID,
				QueryInfo: &planpb.QueryInfo{
					Topk:         defaultTopK,
					MetricType:   metricType,
					SearchParams: "{\"nprobe\":" + strconv.Itoa(defaultNProb) + "}",
					RoundDecimal: defaultRoundDecimal,
				},
				PlaceholderTag: "$0",
			},
		},
	}
}

func genPlaceHolderGroup(nq int64) ([]byte, error) {
	placeholderValue := &commonpb.PlaceholderValue{
		Tag:    "$0",
		Type:   commonpb.PlaceholderType_FloatVector,
		Values: make([][]byte, 0),
	}
	for i := int64(0); i < nq; i++ {
		vec := make([]float32, defaultDim)
		for j := 0; j < defaultDim; j++ {
			vec[j] = rand.Float32()
		}
		var rawData []byte
		for k, ele := range vec {
			buf := make([]byte, 4)
			common.Endian.PutUint32(buf, math.Float32bits(ele+float32(k*2)))
			rawData = append(rawData, buf...)
		}
		placeholderValue.Values = append(placeholderValue.Values, rawData)
	}

	// generate placeholder
	placeholderGroup := commonpb.PlaceholderGroup{
		Placeholders: []*commonpb.PlaceholderValue{placeholderValue},
	}
	placeGroupByte, err := proto.Marshal(&placeholderGroup)
	if err != nil {
		return nil, err
	}
	return placeGroupByte, nil
}

func genSimpleRetrievePlanExpr(schema *schemapb.CollectionSchema) ([]byte, error) {
	pkField, err := typeutil.GetPrimaryFieldSchema(schema)
	if err != nil {
		return nil, err
	}
	planNode := &planpb.PlanNode{
		Node: &planpb.PlanNode_Predicates{
			Predicates: &planpb.Expr{
				Expr: &planpb.Expr_TermExpr{
					TermExpr: &planpb.TermExpr{
						ColumnInfo: &planpb.ColumnInfo{
							FieldId:  pkField.FieldID,
							DataType: pkField.DataType,
						},
						Values: []*planpb.GenericValue{
							{
								Val: &planpb.GenericValue_Int64Val{
									Int64Val: 1,
								},
							},
							{
								Val: &planpb.GenericValue_Int64Val{
									Int64Val: 2,
								},
							},
							{
								Val: &planpb.GenericValue_Int64Val{
									Int64Val: 3,
								},
							},
						},
					},
				},
			},
		},
		OutputFieldIds: []int64{pkField.FieldID, 100},
	}
	planExpr, err := proto.Marshal(planNode)
	return planExpr, err
}