package indexcgowrapper

import (
	"math"
	"math/rand"
	"os"
	"strconv"
	"testing"

	"github.com/stretchr/testify/assert"

	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
	"github.com/milvus-io/milvus/internal/storage"
	"github.com/milvus-io/milvus/pkg/common"
	"github.com/milvus-io/milvus/pkg/proto/indexpb"
	"github.com/milvus-io/milvus/pkg/util/funcutil"
	"github.com/milvus-io/milvus/pkg/util/metric"
	"github.com/milvus-io/milvus/pkg/util/paramtable"
)

func TestMain(m *testing.M) {
	paramtable.Init()
	exitCode := m.Run()
	os.Exit(exitCode)
}

type indexTestCase struct {
	dtype       schemapb.DataType
	typeParams  map[string]string
	indexParams map[string]string
}

func generateBoolArray(numRows int) []bool {
	ret := make([]bool, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, rand.Int()%2 == 0)
	}
	return ret
}

func generateInt8Array(numRows int) []int8 {
	ret := make([]int8, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, int8(rand.Int()))
	}
	return ret
}

func generateInt16Array(numRows int) []int16 {
	ret := make([]int16, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, int16(rand.Int()))
	}
	return ret
}

func generateInt32Array(numRows int) []int32 {
	ret := make([]int32, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, int32(rand.Int()))
	}
	return ret
}

func generateInt64Array(numRows int) []int64 {
	ret := make([]int64, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, int64(rand.Int()))
	}
	return ret
}

func generateFloat32Array(numRows int) []float32 {
	ret := make([]float32, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, rand.Float32())
	}
	return ret
}

func generateFloat64Array(numRows int) []float64 {
	ret := make([]float64, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, rand.Float64())
	}
	return ret
}

func generateStringArray(numRows int) []string {
	ret := make([]string, 0, numRows)
	for i := 0; i < numRows; i++ {
		ret = append(ret, funcutil.GenRandomStr())
	}
	return ret
}

func generateFloatVectors(numRows, dim int) []float32 {
	total := numRows * dim
	ret := make([]float32, 0, total)
	for i := 0; i < total; i++ {
		ret = append(ret, rand.Float32())
	}
	return ret
}

type Float16 uint16

func NewFloat16(f float32) Float16 {
	i := math.Float32bits(f)
	sign := uint16((i >> 31) & 0x1)
	exp := (i >> 23) & 0xff
	exp16 := int16(exp) - 127 + 15
	frac := uint16(i>>13) & 0x3ff
	if exp == 0 {
		exp16 = 0
	} else if exp == 0xff {
		exp16 = 0x1f
	} else {
		if exp16 > 0x1e {
			exp16 = 0x1f
			frac = 0
		} else if exp16 < 0x01 {
			exp16 = 0
			frac = 0
		}
	}
	f16 := (sign << 15) | uint16(exp16<<10) | frac
	return Float16(f16)
}

type BFloat16 uint16

func NewBFloat16(f float32) BFloat16 {
	i := math.Float32bits(f)
	sign := uint16((i >> 31) & 0x1)
	exp := (i >> 23) & 0xff
	exp16 := int16(exp) - 127 + 15
	frac := uint16(i>>13) & 0x3ff
	if exp == 0 {
		exp16 = 0
	} else if exp == 0xff {
		exp16 = 0x1f
	} else {
		if exp16 > 0x1e {
			exp16 = 0x1f
			frac = 0
		} else if exp16 < 0x01 {
			exp16 = 0
			frac = 0
		}
	}
	bf16 := (sign << 15) | uint16(exp16<<10) | frac
	return BFloat16(bf16)
}

func generateFloat16Vectors(numRows, dim int) []byte {
	total := numRows * dim * 2
	ret := make([]byte, total)
	float32Array := generateFloat32Array(numRows * dim)
	for _, f32 := range float32Array {
		f16 := NewFloat16(f32)
		b1 := byte(f16 & 0xff)
		ret = append(ret, b1)
		b2 := byte(f16 >> 8)
		ret = append(ret, b2)
	}
	return ret
}

func generateBFloat16Vectors(numRows, dim int) []byte {
	total := numRows * dim * 2
	ret := make([]byte, total)
	float32Array := generateFloat32Array(numRows * dim)
	for _, f32 := range float32Array {
		bf16 := NewBFloat16(f32)
		b1 := byte(bf16 & 0xff)
		ret = append(ret, b1)
		b2 := byte(bf16 >> 8)
		ret = append(ret, b2)
	}
	return ret
}

func generateBinaryVectors(numRows, dim int) []byte {
	total := (numRows * dim) / 8
	ret := make([]byte, total)
	_, err := rand.Read(ret)
	if err != nil {
		panic(err)
	}
	return ret
}

func genFieldData(dtype schemapb.DataType, numRows, dim int) storage.FieldData {
	switch dtype {
	case schemapb.DataType_Bool:
		return &storage.BoolFieldData{
			Data: generateBoolArray(numRows),
		}
	case schemapb.DataType_Int8:
		return &storage.Int8FieldData{
			Data: generateInt8Array(numRows),
		}
	case schemapb.DataType_Int16:
		return &storage.Int16FieldData{
			Data: generateInt16Array(numRows),
		}
	case schemapb.DataType_Int32:
		return &storage.Int32FieldData{
			Data: generateInt32Array(numRows),
		}
	case schemapb.DataType_Int64:
		return &storage.Int64FieldData{
			Data: generateInt64Array(numRows),
		}
	case schemapb.DataType_Float:
		return &storage.FloatFieldData{
			Data: generateFloat32Array(numRows),
		}
	case schemapb.DataType_Double:
		return &storage.DoubleFieldData{
			Data: generateFloat64Array(numRows),
		}
	case schemapb.DataType_String:
		return &storage.StringFieldData{
			Data: generateStringArray(numRows),
		}
	case schemapb.DataType_VarChar:
		return &storage.StringFieldData{
			Data: generateStringArray(numRows),
		}
	case schemapb.DataType_BinaryVector:
		return &storage.BinaryVectorFieldData{
			Dim:  dim,
			Data: generateBinaryVectors(numRows, dim),
		}
	case schemapb.DataType_FloatVector:
		return &storage.FloatVectorFieldData{
			Data: generateFloatVectors(numRows, dim),
			Dim:  dim,
		}
	case schemapb.DataType_Float16Vector:
		return &storage.Float16VectorFieldData{
			Data: generateFloat16Vectors(numRows, dim),
			Dim:  dim,
		}
	case schemapb.DataType_BFloat16Vector:
		return &storage.BFloat16VectorFieldData{
			Data: generateBFloat16Vectors(numRows, dim),
			Dim:  dim,
		}
	default:
		return nil
	}
}

func genScalarIndexCases(dtype schemapb.DataType) []indexTestCase {
	return []indexTestCase{
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey: "sort",
			},
		},
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey: "flat",
			},
		},
	}
}

func genStringIndexCases(dtype schemapb.DataType) []indexTestCase {
	return []indexTestCase{
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey: "sort",
			},
		},
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey: "marisa-trie",
			},
		},
	}
}

func genFloatVecIndexCases(dtype schemapb.DataType) []indexTestCase {
	return []indexTestCase{
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey:  IndexFaissIVFPQ,
				common.MetricTypeKey: metric.L2,
				common.DimKey:        strconv.Itoa(dim),
				"nlist":              strconv.Itoa(nlist),
				"m":                  strconv.Itoa(m),
				"nbits":              strconv.Itoa(nbits),
			},
		},
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey:  IndexFaissIVFFlat,
				common.MetricTypeKey: metric.L2,
				common.DimKey:        strconv.Itoa(dim),
				"nlist":              strconv.Itoa(nlist),
			},
		},
	}
}

func genBinaryVecIndexCases(dtype schemapb.DataType) []indexTestCase {
	return []indexTestCase{
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey:  IndexFaissBinIVFFlat,
				common.MetricTypeKey: metric.JACCARD,
				common.DimKey:        strconv.Itoa(dim),
				"nlist":              strconv.Itoa(nlist),
				"nbits":              strconv.Itoa(nbits),
			},
		},
	}
}

func genFloat16VecIndexCases(dtype schemapb.DataType) []indexTestCase {
	return []indexTestCase{
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey:  IndexFaissIVFPQ,
				common.MetricTypeKey: metric.L2,
				common.DimKey:        strconv.Itoa(dim),
				"nlist":              strconv.Itoa(nlist),
				"m":                  strconv.Itoa(m),
				"nbits":              strconv.Itoa(nbits),
			},
		},
	}
}

func genBFloat16VecIndexCases(dtype schemapb.DataType) []indexTestCase {
	return []indexTestCase{
		{
			dtype:      dtype,
			typeParams: nil,
			indexParams: map[string]string{
				common.IndexTypeKey:  IndexFaissIVFPQ,
				common.MetricTypeKey: metric.L2,
				common.DimKey:        strconv.Itoa(dim),
				"nlist":              strconv.Itoa(nlist),
				"m":                  strconv.Itoa(m),
				"nbits":              strconv.Itoa(nbits),
			},
		},
	}
}

func genTypedIndexCase(dtype schemapb.DataType) []indexTestCase {
	switch dtype {
	case schemapb.DataType_Bool:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_Int8:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_Int16:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_Int32:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_Int64:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_Float:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_Double:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_String:
		return genScalarIndexCases(dtype)
	case schemapb.DataType_VarChar:
		return genStringIndexCases(dtype)
	case schemapb.DataType_BinaryVector:
		return genBinaryVecIndexCases(dtype)
	case schemapb.DataType_FloatVector:
		return genFloatVecIndexCases(dtype)
	case schemapb.DataType_Float16Vector:
		return genFloat16VecIndexCases(dtype)
	case schemapb.DataType_BFloat16Vector:
		return genBFloat16VecIndexCases(dtype)
	default:
		return nil
	}
}

func genIndexCase() []indexTestCase {
	dtypes := []schemapb.DataType{
		schemapb.DataType_Bool,
		schemapb.DataType_Int8,
		schemapb.DataType_Int16,
		schemapb.DataType_Int32,
		schemapb.DataType_Int64,
		schemapb.DataType_Float,
		schemapb.DataType_Double,
		schemapb.DataType_String,
		schemapb.DataType_VarChar,
		schemapb.DataType_BinaryVector,
		schemapb.DataType_FloatVector,
		schemapb.DataType_Float16Vector,
		schemapb.DataType_BFloat16Vector,
	}
	var ret []indexTestCase
	for _, dtype := range dtypes {
		ret = append(ret, genTypedIndexCase(dtype)...)
	}
	return ret
}

func genStorageConfig() *indexpb.StorageConfig {
	params := paramtable.Get()

	return &indexpb.StorageConfig{
		Address:         params.MinioCfg.Address.GetValue(),
		AccessKeyID:     params.MinioCfg.AccessKeyID.GetValue(),
		SecretAccessKey: params.MinioCfg.SecretAccessKey.GetValue(),
		BucketName:      params.MinioCfg.BucketName.GetValue(),
		RootPath:        params.MinioCfg.RootPath.GetValue(),
		IAMEndpoint:     params.MinioCfg.IAMEndpoint.GetValue(),
		UseSSL:          params.MinioCfg.UseSSL.GetAsBool(),
		SslCACert:       params.MinioCfg.SslCACert.GetValue(),
		UseIAM:          params.MinioCfg.UseIAM.GetAsBool(),
	}
}

func TestCgoIndex(t *testing.T) {
	for _, testCase := range genIndexCase() {
		index, err := NewCgoIndex(testCase.dtype, testCase.typeParams, testCase.indexParams)
		assert.NoError(t, err, testCase)

		dataset := GenDataset(genFieldData(testCase.dtype, nb, dim))
		assert.NoError(t, index.Build(dataset), testCase)

		blobs, err := index.Serialize()
		assert.NoError(t, err, testCase)

		copyIndex, err := NewCgoIndex(testCase.dtype, testCase.typeParams, testCase.indexParams)
		assert.NoError(t, err, testCase)

		assert.NoError(t, copyIndex.Load(blobs), testCase)
	}
}