package planparserv2

import (
	"fmt"
	"strconv"
	"strings"

	"github.com/antlr4-go/antlr/v4"

	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
	parser "github.com/milvus-io/milvus/internal/parser/planparserv2/generated"
	"github.com/milvus-io/milvus/internal/proto/planpb"
	"github.com/milvus-io/milvus/pkg/util/typeutil"
)

type ParserVisitor struct {
	parser.BasePlanVisitor
	schema *typeutil.SchemaHelper
}

func NewParserVisitor(schema *typeutil.SchemaHelper) *ParserVisitor {
	return &ParserVisitor{schema: schema}
}

// VisitParens unpack the parentheses.
func (v *ParserVisitor) VisitParens(ctx *parser.ParensContext) interface{} {
	return ctx.Expr().Accept(v)
}

func (v *ParserVisitor) translateIdentifier(identifier string) (*ExprWithType, error) {
	field, err := v.schema.GetFieldFromNameDefaultJSON(identifier)
	if err != nil {
		return nil, err
	}
	var nestedPath []string
	if identifier != field.Name {
		nestedPath = append(nestedPath, identifier)
	}

	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ColumnExpr{
				ColumnExpr: &planpb.ColumnExpr{
					Info: &planpb.ColumnInfo{
						FieldId:         field.FieldID,
						DataType:        field.DataType,
						IsPrimaryKey:    field.IsPrimaryKey,
						IsAutoID:        field.AutoID,
						NestedPath:      nestedPath,
						IsPartitionKey:  field.IsPartitionKey,
						IsClusteringKey: field.IsClusteringKey,
						ElementType:     field.GetElementType(),
					},
				},
			},
		},
		dataType:      field.DataType,
		nodeDependent: true,
	}, nil
}

// VisitIdentifier translates expr to column plan.
func (v *ParserVisitor) VisitIdentifier(ctx *parser.IdentifierContext) interface{} {
	identifier := ctx.GetText()
	expr, err := v.translateIdentifier(identifier)
	if err != nil {
		return err
	}
	return expr
}

// VisitBoolean translates expr to GenericValue.
func (v *ParserVisitor) VisitBoolean(ctx *parser.BooleanContext) interface{} {
	literal := ctx.BooleanConstant().GetText()
	b, err := strconv.ParseBool(literal)
	if err != nil {
		return err
	}
	return &ExprWithType{
		dataType: schemapb.DataType_Bool,
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value: NewBool(b),
				},
			},
		},
		nodeDependent: true,
	}
}

// VisitInteger translates expr to GenericValue.
func (v *ParserVisitor) VisitInteger(ctx *parser.IntegerContext) interface{} {
	literal := ctx.IntegerConstant().GetText()
	i, err := strconv.ParseInt(literal, 0, 64)
	if err != nil {
		return err
	}
	return &ExprWithType{
		dataType: schemapb.DataType_Int64,
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value: NewInt(i),
				},
			},
		},
		nodeDependent: true,
	}
}

// VisitFloating translates expr to GenericValue.
func (v *ParserVisitor) VisitFloating(ctx *parser.FloatingContext) interface{} {
	literal := ctx.FloatingConstant().GetText()
	f, err := strconv.ParseFloat(literal, 64)
	if err != nil {
		return err
	}
	return &ExprWithType{
		dataType: schemapb.DataType_Double,
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value: NewFloat(f),
				},
			},
		},
		nodeDependent: true,
	}
}

// VisitString translates expr to GenericValue.
func (v *ParserVisitor) VisitString(ctx *parser.StringContext) interface{} {
	pattern, err := convertEscapeSingle(ctx.GetText())
	if err != nil {
		return err
	}
	return &ExprWithType{
		dataType: schemapb.DataType_VarChar,
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value: NewString(pattern),
				},
			},
		},
		nodeDependent: true,
	}
}

func checkDirectComparisonBinaryField(columnInfo *planpb.ColumnInfo) error {
	if typeutil.IsArrayType(columnInfo.GetDataType()) && len(columnInfo.GetNestedPath()) == 0 {
		return fmt.Errorf("can not comparisons array fields directly")
	}
	return nil
}

// VisitAddSub translates expr to arithmetic plan.
func (v *ParserVisitor) VisitAddSub(ctx *parser.AddSubContext) interface{} {
	var err error
	left := ctx.Expr(0).Accept(v)
	if err = getError(left); err != nil {
		return err
	}

	right := ctx.Expr(1).Accept(v)
	if err = getError(right); err != nil {
		return err
	}

	leftValueExpr, rightValueExpr := getValueExpr(left), getValueExpr(right)
	if leftValueExpr != nil && rightValueExpr != nil {
		if isTemplateExpr(leftValueExpr) || isTemplateExpr(rightValueExpr) {
			return fmt.Errorf("placeholder was not supported between two constants with operator: %s", ctx.GetOp().GetText())
		}
		leftValue, rightValue := leftValueExpr.GetValue(), rightValueExpr.GetValue()
		switch ctx.GetOp().GetTokenType() {
		case parser.PlanParserADD:
			return Add(leftValue, rightValue)
		case parser.PlanParserSUB:
			return Subtract(leftValue, rightValue)
		default:
			return fmt.Errorf("unexpected op: %s", ctx.GetOp().GetText())
		}
	}

	leftExpr, rightExpr := getExpr(left), getExpr(right)
	reverse := true

	if leftValueExpr == nil {
		reverse = false
	}

	if leftExpr == nil || rightExpr == nil {
		return fmt.Errorf("invalid arithmetic expression, left: %s, op: %s, right: %s", ctx.Expr(0).GetText(), ctx.GetOp(), ctx.Expr(1).GetText())
	}

	if err = checkDirectComparisonBinaryField(toColumnInfo(leftExpr)); err != nil {
		return err
	}
	if err = checkDirectComparisonBinaryField(toColumnInfo(rightExpr)); err != nil {
		return err
	}
	var dataType schemapb.DataType
	if leftExpr.expr.GetIsTemplate() {
		dataType = rightExpr.dataType
	} else if rightExpr.expr.GetIsTemplate() {
		dataType = leftExpr.dataType
	} else {
		if !canArithmetic(leftExpr.dataType, getArrayElementType(leftExpr), rightExpr.dataType, getArrayElementType(rightExpr)) {
			return fmt.Errorf("'%s' can only be used between integer or floating or json field expressions", arithNameMap[ctx.GetOp().GetTokenType()])
		}

		dataType, err = calcDataType(leftExpr, rightExpr, reverse)
		if err != nil {
			return err
		}
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryArithExpr{
			BinaryArithExpr: &planpb.BinaryArithExpr{
				Left:  leftExpr.expr,
				Right: rightExpr.expr,
				Op:    arithExprMap[ctx.GetOp().GetTokenType()],
			},
		},
		IsTemplate: leftExpr.expr.GetIsTemplate() || rightExpr.expr.GetIsTemplate(),
	}
	return &ExprWithType{
		expr:          expr,
		dataType:      dataType,
		nodeDependent: true,
	}
}

// VisitMulDivMod translates expr to arithmetic plan.
func (v *ParserVisitor) VisitMulDivMod(ctx *parser.MulDivModContext) interface{} {
	var err error
	left := ctx.Expr(0).Accept(v)
	if err := getError(left); err != nil {
		return err
	}

	right := ctx.Expr(1).Accept(v)
	if err := getError(right); err != nil {
		return err
	}

	leftValueExpr, rightValueExpr := getValueExpr(left), getValueExpr(right)
	if leftValueExpr != nil && rightValueExpr != nil {
		if isTemplateExpr(leftValueExpr) || isTemplateExpr(rightValueExpr) {
			return fmt.Errorf("placeholder was not supported between two constants with operator: %s", ctx.GetOp().GetText())
		}
		leftValue, rightValue := getGenericValue(left), getGenericValue(right)
		switch ctx.GetOp().GetTokenType() {
		case parser.PlanParserMUL:
			return Multiply(leftValue, rightValue)
		case parser.PlanParserDIV:
			n, err := Divide(leftValue, rightValue)
			if err != nil {
				return err
			}
			return n
		case parser.PlanParserMOD:
			n, err := Modulo(leftValue, rightValue)
			if err != nil {
				return err
			}
			return n
		default:
			return fmt.Errorf("unexpected op: %s", ctx.GetOp().GetText())
		}
	}

	leftExpr, rightExpr := getExpr(left), getExpr(right)
	reverse := true

	if leftValueExpr == nil {
		reverse = false
	}

	if leftExpr == nil || rightExpr == nil {
		return fmt.Errorf("invalid arithmetic expression, left: %s, op: %s, right: %s", ctx.Expr(0).GetText(), ctx.GetOp(), ctx.Expr(1).GetText())
	}

	if err := checkDirectComparisonBinaryField(toColumnInfo(leftExpr)); err != nil {
		return err
	}
	if err := checkDirectComparisonBinaryField(toColumnInfo(rightExpr)); err != nil {
		return err
	}

	var dataType schemapb.DataType
	if leftExpr.expr.GetIsTemplate() {
		dataType = rightExpr.dataType
	} else if rightExpr.expr.GetIsTemplate() {
		dataType = leftExpr.dataType
	} else {
		if !canArithmetic(leftExpr.dataType, getArrayElementType(leftExpr), rightExpr.dataType, getArrayElementType(rightExpr)) {
			return fmt.Errorf("'%s' can only be used between integer or floating or json field expressions", arithNameMap[ctx.GetOp().GetTokenType()])
		}

		if err = checkValidModArith(arithExprMap[ctx.GetOp().GetTokenType()], leftExpr.dataType, getArrayElementType(leftExpr), rightExpr.dataType, getArrayElementType(rightExpr)); err != nil {
			return err
		}

		dataType, err = calcDataType(leftExpr, rightExpr, reverse)
		if err != nil {
			return err
		}
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryArithExpr{
			BinaryArithExpr: &planpb.BinaryArithExpr{
				Left:  leftExpr.expr,
				Right: rightExpr.expr,
				Op:    arithExprMap[ctx.GetOp().GetTokenType()],
			},
		},
		IsTemplate: leftExpr.expr.GetIsTemplate() || rightExpr.expr.GetIsTemplate(),
	}

	return &ExprWithType{
		expr:          expr,
		dataType:      dataType,
		nodeDependent: true,
	}
}

// VisitEquality translates expr to compare/range plan.
func (v *ParserVisitor) VisitEquality(ctx *parser.EqualityContext) interface{} {
	left := ctx.Expr(0).Accept(v)
	if err := getError(left); err != nil {
		return err
	}

	right := ctx.Expr(1).Accept(v)
	if err := getError(right); err != nil {
		return err
	}

	leftValueExpr, rightValueExpr := getValueExpr(left), getValueExpr(right)
	if leftValueExpr != nil && rightValueExpr != nil {
		if isTemplateExpr(leftValueExpr) || isTemplateExpr(rightValueExpr) {
			return fmt.Errorf("placeholder was not supported between two constants with operator: %s", ctx.GetOp().GetText())
		}
		leftValue, rightValue := leftValueExpr.GetValue(), rightValueExpr.GetValue()
		var ret *ExprWithType
		switch ctx.GetOp().GetTokenType() {
		case parser.PlanParserEQ:
			ret = Equal(leftValue, rightValue)
		case parser.PlanParserNE:
			ret = NotEqual(leftValue, rightValue)
		default:
			return fmt.Errorf("unexpected op: %s", ctx.GetOp().GetText())
		}
		if ret == nil {
			return fmt.Errorf("comparison operations cannot be applied to two incompatible operands: %s", ctx.GetText())
		}
		return ret
	}

	leftExpr, rightExpr := getExpr(left), getExpr(right)

	expr, err := HandleCompare(ctx.GetOp().GetTokenType(), leftExpr, rightExpr)
	if err != nil {
		return err
	}

	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

// VisitRelational translates expr to range/compare plan.
func (v *ParserVisitor) VisitRelational(ctx *parser.RelationalContext) interface{} {
	left := ctx.Expr(0).Accept(v)
	if err := getError(left); err != nil {
		return err
	}

	right := ctx.Expr(1).Accept(v)
	if err := getError(right); err != nil {
		return err
	}
	leftValueExpr, rightValueExpr := getValueExpr(left), getValueExpr(right)
	if leftValueExpr != nil && rightValueExpr != nil {
		if isTemplateExpr(leftValueExpr) || isTemplateExpr(rightValueExpr) {
			return fmt.Errorf("placeholder was not supported between two constants with operator: %s", ctx.GetOp().GetText())
		}
		leftValue, rightValue := getGenericValue(left), getGenericValue(right)
		var ret *ExprWithType
		switch ctx.GetOp().GetTokenType() {
		case parser.PlanParserLT:
			ret = Less(leftValue, rightValue)
		case parser.PlanParserLE:
			ret = LessEqual(leftValue, rightValue)
		case parser.PlanParserGT:
			ret = Greater(leftValue, rightValue)
		case parser.PlanParserGE:
			ret = GreaterEqual(leftValue, rightValue)
		default:
			return fmt.Errorf("unexpected op: %s", ctx.GetOp().GetText())
		}
		if ret == nil {
			return fmt.Errorf("comparison operations cannot be applied to two incompatible operands: %s", ctx.GetText())
		}
		return ret
	}

	leftExpr, rightExpr := getExpr(left), getExpr(right)
	if err := checkDirectComparisonBinaryField(toColumnInfo(leftExpr)); err != nil {
		return err
	}
	if err := checkDirectComparisonBinaryField(toColumnInfo(rightExpr)); err != nil {
		return err
	}

	expr, err := HandleCompare(ctx.GetOp().GetTokenType(), leftExpr, rightExpr)
	if err != nil {
		return err
	}

	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

// VisitLike handles match operations.
func (v *ParserVisitor) VisitLike(ctx *parser.LikeContext) interface{} {
	left := ctx.Expr().Accept(v)
	if err := getError(left); err != nil {
		return err
	}

	leftExpr := getExpr(left)
	if leftExpr == nil {
		return fmt.Errorf("the left operand of like is invalid")
	}

	column := toColumnInfo(leftExpr)
	if column == nil {
		return fmt.Errorf("like operation on complicated expr is unsupported")
	}
	if err := checkDirectComparisonBinaryField(column); err != nil {
		return err
	}

	if !typeutil.IsStringType(leftExpr.dataType) && !typeutil.IsJSONType(leftExpr.dataType) &&
		!(typeutil.IsArrayType(leftExpr.dataType) && typeutil.IsStringType(column.GetElementType())) {
		return fmt.Errorf("like operation on non-string or no-json field is unsupported")
	}

	pattern, err := convertEscapeSingle(ctx.StringLiteral().GetText())
	if err != nil {
		return err
	}

	op, operand, err := translatePatternMatch(pattern)
	if err != nil {
		return err
	}

	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_UnaryRangeExpr{
				UnaryRangeExpr: &planpb.UnaryRangeExpr{
					ColumnInfo: column,
					Op:         op,
					Value:      NewString(operand),
				},
			},
		},
		dataType: schemapb.DataType_Bool,
	}
}

func (v *ParserVisitor) VisitTextMatch(ctx *parser.TextMatchContext) interface{} {
	column, err := v.translateIdentifier(ctx.Identifier().GetText())
	if err != nil {
		return err
	}
	if !typeutil.IsStringType(column.dataType) {
		return fmt.Errorf("text match operation on non-string is unsupported")
	}

	queryText, err := convertEscapeSingle(ctx.StringLiteral().GetText())
	if err != nil {
		return err
	}

	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_UnaryRangeExpr{
				UnaryRangeExpr: &planpb.UnaryRangeExpr{
					ColumnInfo: toColumnInfo(column),
					Op:         planpb.OpType_TextMatch,
					Value:      NewString(queryText),
				},
			},
		},
		dataType: schemapb.DataType_Bool,
	}
}

// VisitTerm translates expr to term plan.
func (v *ParserVisitor) VisitTerm(ctx *parser.TermContext) interface{} {
	child := ctx.Expr(0).Accept(v)
	if err := getError(child); err != nil {
		return err
	}

	if childValue := getGenericValue(child); childValue != nil {
		return fmt.Errorf("'term' can only be used on non-const expression, but got: %s", ctx.Expr(0).GetText())
	}

	childExpr := getExpr(child)
	columnInfo := toColumnInfo(childExpr)
	if columnInfo == nil {
		return fmt.Errorf("'term' can only be used on single field, but got: %s", ctx.Expr(0).GetText())
	}

	dataType := columnInfo.GetDataType()
	if typeutil.IsArrayType(dataType) && len(columnInfo.GetNestedPath()) != 0 {
		dataType = columnInfo.GetElementType()
	}

	term := ctx.Expr(1).Accept(v)
	if getError(term) != nil {
		return term
	}

	valueExpr := getValueExpr(term)
	var placeholder string
	var isTemplate bool
	var values []*planpb.GenericValue
	if valueExpr.GetValue() == nil && valueExpr.GetTemplateVariableName() != "" {
		placeholder = valueExpr.GetTemplateVariableName()
		values = nil
		isTemplate = true
	} else {
		elementValue := valueExpr.GetValue()
		if elementValue == nil {
			return fmt.Errorf("value '%s' in list cannot be a non-const expression", ctx.Expr(1).GetText())
		}

		if !IsArray(elementValue) {
			return fmt.Errorf("the right-hand side of 'in' must be a list, but got: %s", ctx.Expr(1).GetText())
		}
		array := elementValue.GetArrayVal().GetArray()
		values = make([]*planpb.GenericValue, len(array))
		for i, e := range array {
			castedValue, err := castValue(dataType, e)
			if err != nil {
				return fmt.Errorf("value '%s' in list cannot be casted to %s", e.String(), dataType.String())
			}
			values[i] = castedValue
		}
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_TermExpr{
			TermExpr: &planpb.TermExpr{
				ColumnInfo:           columnInfo,
				Values:               values,
				TemplateVariableName: placeholder,
			},
		},
		IsTemplate: isTemplate,
	}
	if ctx.GetOp() != nil {
		expr = &planpb.Expr{
			Expr: &planpb.Expr_UnaryExpr{
				UnaryExpr: &planpb.UnaryExpr{
					Op:    planpb.UnaryExpr_Not,
					Child: expr,
				},
			},
			IsTemplate: isTemplate,
		}
	}
	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

func (v *ParserVisitor) getChildColumnInfo(identifier, child antlr.TerminalNode) (*planpb.ColumnInfo, error) {
	if identifier != nil {
		childExpr, err := v.translateIdentifier(identifier.GetText())
		if err != nil {
			return nil, err
		}
		return toColumnInfo(childExpr), nil
	}

	return v.getColumnInfoFromJSONIdentifier(child.GetText())
}

// VisitCall parses the expr to call plan.
func (v *ParserVisitor) VisitCall(ctx *parser.CallContext) interface{} {
	functionName := strings.ToLower(ctx.Identifier().GetText())
	numParams := len(ctx.AllExpr())
	funcParameters := make([]*planpb.Expr, 0, numParams)
	for _, param := range ctx.AllExpr() {
		paramExpr := getExpr(param.Accept(v))
		funcParameters = append(funcParameters, paramExpr.expr)
	}
	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_CallExpr{
				CallExpr: &planpb.CallExpr{
					FunctionName:       functionName,
					FunctionParameters: funcParameters,
				},
			},
		},
		dataType: schemapb.DataType_Bool,
	}
}

// VisitRange translates expr to range plan.
func (v *ParserVisitor) VisitRange(ctx *parser.RangeContext) interface{} {
	columnInfo, err := v.getChildColumnInfo(ctx.Identifier(), ctx.JSONIdentifier())
	if err != nil {
		return err
	}
	if columnInfo == nil {
		return fmt.Errorf("range operations are only supported on single fields now, got: %s", ctx.Expr(1).GetText())
	}
	if err := checkDirectComparisonBinaryField(columnInfo); err != nil {
		return err
	}

	lower := ctx.Expr(0).Accept(v)
	upper := ctx.Expr(1).Accept(v)
	if err := getError(lower); err != nil {
		return err
	}
	if err := getError(upper); err != nil {
		return err
	}

	lowerValueExpr, upperValueExpr := getValueExpr(lower), getValueExpr(upper)
	if lowerValueExpr == nil {
		return fmt.Errorf("lowerbound cannot be a non-const expression: %s", ctx.Expr(0).GetText())
	}
	if upperValueExpr == nil {
		return fmt.Errorf("upperbound cannot be a non-const expression: %s", ctx.Expr(1).GetText())
	}

	fieldDataType := columnInfo.GetDataType()
	if typeutil.IsArrayType(columnInfo.GetDataType()) {
		fieldDataType = columnInfo.GetElementType()
	}

	lowerValue := lowerValueExpr.GetValue()
	upperValue := upperValueExpr.GetValue()
	if !isTemplateExpr(lowerValueExpr) {
		if lowerValue, err = castRangeValue(fieldDataType, lowerValue); err != nil {
			return err
		}
	}
	if !isTemplateExpr(upperValueExpr) {
		if upperValue, err = castRangeValue(fieldDataType, upperValue); err != nil {
			return err
		}
	}
	lowerInclusive := ctx.GetOp1().GetTokenType() == parser.PlanParserLE
	upperInclusive := ctx.GetOp2().GetTokenType() == parser.PlanParserLE
	if !isTemplateExpr(lowerValueExpr) && !isTemplateExpr(upperValueExpr) {
		if !(lowerInclusive && upperInclusive) {
			if getGenericValue(GreaterEqual(lowerValue, upperValue)).GetBoolVal() {
				return fmt.Errorf("invalid range: lowerbound is greater than upperbound")
			}
		} else {
			if getGenericValue(Greater(lowerValue, upperValue)).GetBoolVal() {
				return fmt.Errorf("invalid range: lowerbound is greater than upperbound")
			}
		}
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryRangeExpr{
			BinaryRangeExpr: &planpb.BinaryRangeExpr{
				ColumnInfo:                columnInfo,
				LowerInclusive:            lowerInclusive,
				UpperInclusive:            upperInclusive,
				LowerValue:                lowerValue,
				UpperValue:                upperValue,
				LowerTemplateVariableName: lowerValueExpr.GetTemplateVariableName(),
				UpperTemplateVariableName: upperValueExpr.GetTemplateVariableName(),
			},
		},
		IsTemplate: isTemplateExpr(lowerValueExpr) || isTemplateExpr(upperValueExpr),
	}
	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

// VisitReverseRange parses the expression like "1 > a > 0".
func (v *ParserVisitor) VisitReverseRange(ctx *parser.ReverseRangeContext) interface{} {
	columnInfo, err := v.getChildColumnInfo(ctx.Identifier(), ctx.JSONIdentifier())
	if err != nil {
		return err
	}
	if columnInfo == nil {
		return fmt.Errorf("range operations are only supported on single fields now, got: %s", ctx.Expr(1).GetText())
	}

	if err := checkDirectComparisonBinaryField(columnInfo); err != nil {
		return err
	}

	lower := ctx.Expr(1).Accept(v)
	upper := ctx.Expr(0).Accept(v)
	if err := getError(lower); err != nil {
		return err
	}
	if err := getError(upper); err != nil {
		return err
	}

	lowerValueExpr, upperValueExpr := getValueExpr(lower), getValueExpr(upper)
	if lowerValueExpr == nil {
		return fmt.Errorf("lowerbound cannot be a non-const expression: %s", ctx.Expr(0).GetText())
	}
	if upperValueExpr == nil {
		return fmt.Errorf("upperbound cannot be a non-const expression: %s", ctx.Expr(1).GetText())
	}

	fieldDataType := columnInfo.GetDataType()
	if typeutil.IsArrayType(columnInfo.GetDataType()) {
		fieldDataType = columnInfo.GetElementType()
	}

	lowerValue := lowerValueExpr.GetValue()
	upperValue := upperValueExpr.GetValue()
	if !isTemplateExpr(lowerValueExpr) {
		if lowerValue, err = castRangeValue(fieldDataType, lowerValue); err != nil {
			return err
		}
	}
	if !isTemplateExpr(upperValueExpr) {
		if upperValue, err = castRangeValue(fieldDataType, upperValue); err != nil {
			return err
		}
	}
	lowerInclusive := ctx.GetOp2().GetTokenType() == parser.PlanParserGE
	upperInclusive := ctx.GetOp1().GetTokenType() == parser.PlanParserGE
	if !isTemplateExpr(lowerValueExpr) && !isTemplateExpr(upperValueExpr) {
		if !(lowerInclusive && upperInclusive) {
			if getGenericValue(GreaterEqual(lowerValue, upperValue)).GetBoolVal() {
				return fmt.Errorf("invalid range: lowerbound is greater than upperbound")
			}
		} else {
			if getGenericValue(Greater(lowerValue, upperValue)).GetBoolVal() {
				return fmt.Errorf("invalid range: lowerbound is greater than upperbound")
			}
		}
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryRangeExpr{
			BinaryRangeExpr: &planpb.BinaryRangeExpr{
				ColumnInfo:                columnInfo,
				LowerInclusive:            lowerInclusive,
				UpperInclusive:            upperInclusive,
				LowerValue:                lowerValue,
				UpperValue:                upperValue,
				LowerTemplateVariableName: lowerValueExpr.GetTemplateVariableName(),
				UpperTemplateVariableName: upperValueExpr.GetTemplateVariableName(),
			},
		},
		IsTemplate: isTemplateExpr(lowerValueExpr) || isTemplateExpr(upperValueExpr),
	}
	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

// VisitUnary unpack the +expr to expr.
func (v *ParserVisitor) VisitUnary(ctx *parser.UnaryContext) interface{} {
	child := ctx.Expr().Accept(v)
	if err := getError(child); err != nil {
		return err
	}

	childValue := getGenericValue(child)
	if childValue != nil {
		switch ctx.GetOp().GetTokenType() {
		case parser.PlanParserADD:
			return child
		case parser.PlanParserSUB:
			return Negative(childValue)
		case parser.PlanParserNOT:
			return Not(childValue)
		default:
			return fmt.Errorf("unexpected op: %s", ctx.GetOp().GetText())
		}
	}

	childExpr := getExpr(child)
	if childExpr == nil {
		return fmt.Errorf("failed to parse unary expressions")
	}
	if err := checkDirectComparisonBinaryField(toColumnInfo(childExpr)); err != nil {
		return err
	}
	switch ctx.GetOp().GetTokenType() {
	case parser.PlanParserADD:
		return childExpr
	case parser.PlanParserNOT:
		if !canBeExecuted(childExpr) {
			return fmt.Errorf("%s op can only be applied on boolean expression", unaryLogicalNameMap[parser.PlanParserNOT])
		}
		return &ExprWithType{
			expr: &planpb.Expr{
				Expr: &planpb.Expr_UnaryExpr{
					UnaryExpr: &planpb.UnaryExpr{
						Op:    unaryLogicalOpMap[parser.PlanParserNOT],
						Child: childExpr.expr,
					},
				},
			},
			dataType: schemapb.DataType_Bool,
		}
	default:
		return fmt.Errorf("unexpected op: %s", ctx.GetOp().GetText())
	}
}

// VisitLogicalOr apply logical or to two boolean expressions.
func (v *ParserVisitor) VisitLogicalOr(ctx *parser.LogicalOrContext) interface{} {
	left := ctx.Expr(0).Accept(v)
	if err := getError(left); err != nil {
		return err
	}
	right := ctx.Expr(1).Accept(v)
	if err := getError(right); err != nil {
		return err
	}

	leftValue, rightValue := getGenericValue(left), getGenericValue(right)
	if leftValue != nil && rightValue != nil {
		n, err := Or(leftValue, rightValue)
		if err != nil {
			return err
		}
		return n
	}

	if leftValue != nil || rightValue != nil {
		return fmt.Errorf("'or' can only be used between boolean expressions")
	}

	var leftExpr *ExprWithType
	var rightExpr *ExprWithType
	leftExpr = getExpr(left)
	rightExpr = getExpr(right)

	if !canBeExecuted(leftExpr) || !canBeExecuted(rightExpr) {
		return fmt.Errorf("'or' can only be used between boolean expressions")
	}
	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryExpr{
			BinaryExpr: &planpb.BinaryExpr{
				Left:  leftExpr.expr,
				Right: rightExpr.expr,
				Op:    planpb.BinaryExpr_LogicalOr,
			},
		},
		IsTemplate: leftExpr.expr.GetIsTemplate() || rightExpr.expr.GetIsTemplate(),
	}

	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

// VisitLogicalAnd apply logical and to two boolean expressions.
func (v *ParserVisitor) VisitLogicalAnd(ctx *parser.LogicalAndContext) interface{} {
	left := ctx.Expr(0).Accept(v)
	if err := getError(left); err != nil {
		return err
	}
	right := ctx.Expr(1).Accept(v)
	if err := getError(right); err != nil {
		return err
	}

	leftValue, rightValue := getGenericValue(left), getGenericValue(right)
	if leftValue != nil && rightValue != nil {
		n, err := And(leftValue, rightValue)
		if err != nil {
			return err
		}
		return n
	}

	if leftValue != nil || rightValue != nil {
		return fmt.Errorf("'and' can only be used between boolean expressions")
	}

	var leftExpr *ExprWithType
	var rightExpr *ExprWithType
	leftExpr = getExpr(left)
	rightExpr = getExpr(right)

	if !canBeExecuted(leftExpr) || !canBeExecuted(rightExpr) {
		return fmt.Errorf("'and' can only be used between boolean expressions")
	}
	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryExpr{
			BinaryExpr: &planpb.BinaryExpr{
				Left:  leftExpr.expr,
				Right: rightExpr.expr,
				Op:    planpb.BinaryExpr_LogicalAnd,
			},
		},
		IsTemplate: leftExpr.expr.GetIsTemplate() || rightExpr.expr.GetIsTemplate(),
	}

	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

// VisitBitXor not supported.
func (v *ParserVisitor) VisitBitXor(ctx *parser.BitXorContext) interface{} {
	return fmt.Errorf("BitXor is not supported: %s", ctx.GetText())
}

// VisitBitAnd not supported.
func (v *ParserVisitor) VisitBitAnd(ctx *parser.BitAndContext) interface{} {
	return fmt.Errorf("BitAnd is not supported: %s", ctx.GetText())
}

// VisitPower parses power expression.
func (v *ParserVisitor) VisitPower(ctx *parser.PowerContext) interface{} {
	left := ctx.Expr(0).Accept(v)
	if err := getError(left); err != nil {
		return err
	}

	right := ctx.Expr(1).Accept(v)
	if err := getError(right); err != nil {
		return err
	}

	leftValue, rightValue := getGenericValue(left), getGenericValue(right)
	if leftValue != nil && rightValue != nil {
		return Power(leftValue, rightValue)
	}

	return fmt.Errorf("power can only apply on constants: %s", ctx.GetText())
}

// VisitShift unsupported.
func (v *ParserVisitor) VisitShift(ctx *parser.ShiftContext) interface{} {
	return fmt.Errorf("shift is not supported: %s", ctx.GetText())
}

// VisitBitOr unsupported.
func (v *ParserVisitor) VisitBitOr(ctx *parser.BitOrContext) interface{} {
	return fmt.Errorf("BitOr is not supported: %s", ctx.GetText())
}

// getColumnInfoFromJSONIdentifier parse JSON field name and JSON nested path.
// input: user["name"]["first"],
// output: if user is JSON field name, and fieldID is 102
/*
&planpb.ColumnInfo{
	FieldId:    102,
	DataType:   JSON,
	NestedPath: []string{"name", "first"},
}, nil
*/
// if user is not JSON field name, and $SYS_META fieldID is 102:
/*
&planpb.ColumnInfo{
	FieldId:    102,
	DataType:   JSON,
	NestedPath: []string{"user", "name", "first"},
}, nil
*/
// input: user,
// output: if user is JSON field name, return error.
// if user is not JSON field name, and $SYS_META fieldID is 102:
/*
&planpb.ColumnInfo{
	FieldId:    102,
	DataType:   JSON,
	NestedPath: []string{"user"},
}, nil
*/
// More tests refer to plan_parser_v2_test.go::Test_JSONExpr
func (v *ParserVisitor) getColumnInfoFromJSONIdentifier(identifier string) (*planpb.ColumnInfo, error) {
	fieldName := strings.Split(identifier, "[")[0]
	nestedPath := make([]string, 0)
	field, err := v.schema.GetFieldFromNameDefaultJSON(fieldName)
	if err != nil {
		return nil, err
	}
	if field.GetDataType() != schemapb.DataType_JSON &&
		field.GetDataType() != schemapb.DataType_Array {
		errMsg := fmt.Sprintf("%s data type not supported accessed with []", field.GetDataType())
		return nil, fmt.Errorf(errMsg)
	}
	if fieldName != field.Name {
		nestedPath = append(nestedPath, fieldName)
	}
	jsonKeyStr := identifier[len(fieldName):]
	ss := strings.Split(jsonKeyStr, "][")
	for i := 0; i < len(ss); i++ {
		path := strings.Trim(ss[i], "[]")
		if path == "" {
			return nil, fmt.Errorf("invalid identifier: %s", identifier)
		}
		if (strings.HasPrefix(path, "\"") && strings.HasSuffix(path, "\"")) ||
			(strings.HasPrefix(path, "'") && strings.HasSuffix(path, "'")) {
			path = path[1 : len(path)-1]
			if path == "" {
				return nil, fmt.Errorf("invalid identifier: %s", identifier)
			}
			if typeutil.IsArrayType(field.DataType) {
				return nil, fmt.Errorf("can only access array field with integer index")
			}
		} else if _, err := strconv.ParseInt(path, 10, 64); err != nil {
			return nil, fmt.Errorf("json key must be enclosed in double quotes or single quotes: \"%s\"", path)
		}
		nestedPath = append(nestedPath, path)
	}

	return &planpb.ColumnInfo{
		FieldId:     field.FieldID,
		DataType:    field.DataType,
		NestedPath:  nestedPath,
		ElementType: field.GetElementType(),
	}, nil
}

func (v *ParserVisitor) VisitJSONIdentifier(ctx *parser.JSONIdentifierContext) interface{} {
	field, err := v.getColumnInfoFromJSONIdentifier(ctx.JSONIdentifier().GetText())
	if err != nil {
		return err
	}
	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ColumnExpr{
				ColumnExpr: &planpb.ColumnExpr{
					Info: &planpb.ColumnInfo{
						FieldId:     field.GetFieldId(),
						DataType:    field.GetDataType(),
						NestedPath:  field.GetNestedPath(),
						ElementType: field.GetElementType(),
					},
				},
			},
		},
		dataType:      field.GetDataType(),
		nodeDependent: true,
	}
}

func (v *ParserVisitor) VisitExists(ctx *parser.ExistsContext) interface{} {
	child := ctx.Expr().Accept(v)
	if err := getError(child); err != nil {
		return err
	}
	columnInfo := toColumnInfo(child.(*ExprWithType))
	if columnInfo == nil {
		return fmt.Errorf(
			"exists operations are only supported on single fields now, got: %s", ctx.Expr().GetText())
	}

	if columnInfo.GetDataType() != schemapb.DataType_JSON {
		return fmt.Errorf(
			"exists operations are only supportted on json field, got:%s", columnInfo.GetDataType())
	}

	if len(columnInfo.GetNestedPath()) == 0 {
		return fmt.Errorf(
			"exists operations are only supportted on json key")
	}

	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ExistsExpr{
				ExistsExpr: &planpb.ExistsExpr{
					Info: &planpb.ColumnInfo{
						FieldId:    columnInfo.GetFieldId(),
						DataType:   columnInfo.GetDataType(),
						NestedPath: columnInfo.GetNestedPath(),
					},
				},
			},
		},
		dataType: schemapb.DataType_Bool,
	}
}

func (v *ParserVisitor) VisitArray(ctx *parser.ArrayContext) interface{} {
	allExpr := ctx.AllExpr()
	array := make([]*planpb.GenericValue, len(allExpr))
	dType := schemapb.DataType_None
	sameType := true
	for i := 0; i < len(allExpr); i++ {
		element := allExpr[i].Accept(v)
		if err := getError(element); err != nil {
			return err
		}
		elementValue := getGenericValue(element)
		if elementValue == nil {
			return fmt.Errorf("array element type must be generic value, but got: %s", allExpr[i].GetText())
		}
		array[i] = elementValue

		if dType == schemapb.DataType_None {
			dType = element.(*ExprWithType).dataType
		} else if dType != element.(*ExprWithType).dataType {
			sameType = false
		}
	}
	if !sameType {
		dType = schemapb.DataType_None
	}

	return &ExprWithType{
		dataType: schemapb.DataType_Array,
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value: &planpb.GenericValue{
						Val: &planpb.GenericValue_ArrayVal{
							ArrayVal: &planpb.Array{
								Array:       array,
								SameType:    sameType,
								ElementType: dType,
							},
						},
					},
				},
			},
		},
		nodeDependent: true,
	}
}

func (v *ParserVisitor) VisitEmptyArray(ctx *parser.EmptyArrayContext) interface{} {
	return &ExprWithType{
		dataType: schemapb.DataType_Array,
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value: &planpb.GenericValue{
						Val: &planpb.GenericValue_ArrayVal{
							ArrayVal: &planpb.Array{
								Array:       nil,
								SameType:    true,
								ElementType: schemapb.DataType_None,
							},
						},
					},
				},
			},
		},
		nodeDependent: true,
	}
}

func (v *ParserVisitor) VisitJSONContains(ctx *parser.JSONContainsContext) interface{} {
	field := ctx.Expr(0).Accept(v)
	if err := getError(field); err != nil {
		return err
	}

	columnInfo := toColumnInfo(field.(*ExprWithType))
	if columnInfo == nil ||
		(!typeutil.IsJSONType(columnInfo.GetDataType()) && !typeutil.IsArrayType(columnInfo.GetDataType())) {
		return fmt.Errorf(
			"contains operation are only supported on json or array fields now, got: %s", ctx.Expr(0).GetText())
	}

	element := ctx.Expr(1).Accept(v)
	if err := getError(element); err != nil {
		return err
	}
	elementExpr := getValueExpr(element)
	if elementExpr == nil {
		return fmt.Errorf(
			"contains operation are only supported explicitly specified element, got: %s", ctx.Expr(1).GetText())
	}
	var elements []*planpb.GenericValue

	if !isTemplateExpr(elementExpr) {
		elements = make([]*planpb.GenericValue, 1)
		elementValue := elementExpr.GetValue()
		if err := checkContainsElement(field.(*ExprWithType), planpb.JSONContainsExpr_Contains, elementValue); err != nil {
			return err
		}
		elements[0] = elementValue
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_JsonContainsExpr{
			JsonContainsExpr: &planpb.JSONContainsExpr{
				ColumnInfo:           columnInfo,
				Elements:             elements,
				Op:                   planpb.JSONContainsExpr_Contains,
				ElementsSameType:     true,
				TemplateVariableName: elementExpr.GetTemplateVariableName(),
			},
		},
		IsTemplate: isTemplateExpr(elementExpr),
	}
	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

func (v *ParserVisitor) VisitJSONContainsAll(ctx *parser.JSONContainsAllContext) interface{} {
	field := ctx.Expr(0).Accept(v)
	if err := getError(field); err != nil {
		return err
	}

	columnInfo := toColumnInfo(field.(*ExprWithType))
	if columnInfo == nil ||
		(!typeutil.IsJSONType(columnInfo.GetDataType()) && !typeutil.IsArrayType(columnInfo.GetDataType())) {
		return fmt.Errorf(
			"contains_all operation are only supported on json or array fields now, got: %s", ctx.Expr(0).GetText())
	}

	element := ctx.Expr(1).Accept(v)
	if err := getError(element); err != nil {
		return err
	}

	elementExpr := getValueExpr(element)
	if elementExpr == nil {
		return fmt.Errorf(
			"contains_all operation are only supported explicitly specified element, got: %s", ctx.Expr(1).GetText())
	}

	var elements []*planpb.GenericValue
	var sameType bool
	if !isTemplateExpr(elementExpr) {
		elementValue := elementExpr.GetValue()
		if err := checkContainsElement(field.(*ExprWithType), planpb.JSONContainsExpr_ContainsAll, elementValue); err != nil {
			return err
		}
		elements = elementValue.GetArrayVal().GetArray()
		sameType = elementValue.GetArrayVal().GetSameType()
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_JsonContainsExpr{
			JsonContainsExpr: &planpb.JSONContainsExpr{
				ColumnInfo:           columnInfo,
				Elements:             elements,
				Op:                   planpb.JSONContainsExpr_ContainsAll,
				ElementsSameType:     sameType,
				TemplateVariableName: elementExpr.GetTemplateVariableName(),
			},
		},
		IsTemplate: isTemplateExpr(elementExpr),
	}
	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

func (v *ParserVisitor) VisitJSONContainsAny(ctx *parser.JSONContainsAnyContext) interface{} {
	field := ctx.Expr(0).Accept(v)
	if err := getError(field); err != nil {
		return err
	}

	columnInfo := toColumnInfo(field.(*ExprWithType))
	if columnInfo == nil ||
		(!typeutil.IsJSONType(columnInfo.GetDataType()) && !typeutil.IsArrayType(columnInfo.GetDataType())) {
		return fmt.Errorf(
			"contains_any operation are only supported on json or array fields now, got: %s", ctx.Expr(0).GetText())
	}

	element := ctx.Expr(1).Accept(v)
	if err := getError(element); err != nil {
		return err
	}
	valueExpr := getValueExpr(element)

	if valueExpr == nil {
		return fmt.Errorf(
			"contains_any operation are only supported explicitly specified element, got: %s", ctx.Expr(1).GetText())
	}

	var elements []*planpb.GenericValue
	var sameType bool
	if !isTemplateExpr(valueExpr) {
		elementValue := valueExpr.GetValue()
		if err := checkContainsElement(field.(*ExprWithType), planpb.JSONContainsExpr_ContainsAny, elementValue); err != nil {
			return err
		}
		elements = elementValue.GetArrayVal().GetArray()
		sameType = elementValue.GetArrayVal().GetSameType()
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_JsonContainsExpr{
			JsonContainsExpr: &planpb.JSONContainsExpr{
				ColumnInfo:           columnInfo,
				Elements:             elements,
				Op:                   planpb.JSONContainsExpr_ContainsAny,
				ElementsSameType:     sameType,
				TemplateVariableName: valueExpr.GetTemplateVariableName(),
			},
		},
		IsTemplate: isTemplateExpr(valueExpr),
	}
	return &ExprWithType{
		expr:     expr,
		dataType: schemapb.DataType_Bool,
	}
}

func (v *ParserVisitor) VisitArrayLength(ctx *parser.ArrayLengthContext) interface{} {
	columnInfo, err := v.getChildColumnInfo(ctx.Identifier(), ctx.JSONIdentifier())
	if err != nil {
		return err
	}
	if columnInfo == nil ||
		(!typeutil.IsJSONType(columnInfo.GetDataType()) && !typeutil.IsArrayType(columnInfo.GetDataType())) {
		return fmt.Errorf(
			"array_length operation are only supported on json or array fields now, got: %s", ctx.GetText())
	}

	expr := &planpb.Expr{
		Expr: &planpb.Expr_BinaryArithExpr{
			BinaryArithExpr: &planpb.BinaryArithExpr{
				Left: &planpb.Expr{
					Expr: &planpb.Expr_ColumnExpr{
						ColumnExpr: &planpb.ColumnExpr{
							Info: columnInfo,
						},
					},
				},
				Right: nil,
				Op:    planpb.ArithOpType_ArrayLength,
			},
		},
	}
	return &ExprWithType{
		expr:          expr,
		dataType:      schemapb.DataType_Int64,
		nodeDependent: true,
	}
}

func (v *ParserVisitor) VisitTemplateVariable(ctx *parser.TemplateVariableContext) interface{} {
	return &ExprWithType{
		expr: &planpb.Expr{
			Expr: &planpb.Expr_ValueExpr{
				ValueExpr: &planpb.ValueExpr{
					Value:                nil,
					TemplateVariableName: ctx.Identifier().GetText(),
				},
			},
			IsTemplate: true,
		},
	}
}