/
point.go
214 lines (182 loc) · 4.08 KB
/
point.go
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package pgtype
import (
"bytes"
"database/sql/driver"
"encoding/binary"
"fmt"
"math"
"strconv"
"strings"
"github.com/jackc/pgio"
)
type Vec2 struct {
X float64
Y float64
}
type Point struct {
P Vec2
Status Status
}
func (dst *Point) Set(src interface{}) error {
if src == nil {
dst.Status = Null
return nil
}
err := fmt.Errorf("cannot convert %v to Point", src)
var p *Point
switch value := src.(type) {
case string:
p, err = parsePoint([]byte(value))
case []byte:
p, err = parsePoint(value)
default:
return err
}
if err != nil {
return err
}
*dst = *p
return nil
}
func parsePoint(src []byte) (*Point, error) {
if src == nil || bytes.Equal(src, []byte("null")) {
return &Point{Status: Null}, nil
}
if len(src) < 5 {
return nil, fmt.Errorf("invalid length for point: %v", len(src))
}
if src[0] == '"' && src[len(src)-1] == '"' {
src = src[1 : len(src)-1]
}
parts := strings.SplitN(string(src[1:len(src)-1]), ",", 2)
if len(parts) < 2 {
return nil, fmt.Errorf("invalid format for point")
}
x, err := strconv.ParseFloat(parts[0], 64)
if err != nil {
return nil, err
}
y, err := strconv.ParseFloat(parts[1], 64)
if err != nil {
return nil, err
}
return &Point{P: Vec2{x, y}, Status: Present}, nil
}
func (dst Point) Get() interface{} {
switch dst.Status {
case Present:
return dst
case Null:
return nil
default:
return dst.Status
}
}
func (src *Point) AssignTo(dst interface{}) error {
return fmt.Errorf("cannot assign %v to %T", src, dst)
}
func (dst *Point) DecodeText(ci *ConnInfo, src []byte) error {
if src == nil {
*dst = Point{Status: Null}
return nil
}
if len(src) < 5 {
return fmt.Errorf("invalid length for point: %v", len(src))
}
parts := strings.SplitN(string(src[1:len(src)-1]), ",", 2)
if len(parts) < 2 {
return fmt.Errorf("invalid format for point")
}
x, err := strconv.ParseFloat(parts[0], 64)
if err != nil {
return err
}
y, err := strconv.ParseFloat(parts[1], 64)
if err != nil {
return err
}
*dst = Point{P: Vec2{x, y}, Status: Present}
return nil
}
func (dst *Point) DecodeBinary(ci *ConnInfo, src []byte) error {
if src == nil {
*dst = Point{Status: Null}
return nil
}
if len(src) != 16 {
return fmt.Errorf("invalid length for point: %v", len(src))
}
x := binary.BigEndian.Uint64(src)
y := binary.BigEndian.Uint64(src[8:])
*dst = Point{
P: Vec2{math.Float64frombits(x), math.Float64frombits(y)},
Status: Present,
}
return nil
}
func (src Point) EncodeText(ci *ConnInfo, buf []byte) ([]byte, error) {
switch src.Status {
case Null:
return nil, nil
case Undefined:
return nil, errUndefined
}
return append(buf, fmt.Sprintf(`(%s,%s)`,
strconv.FormatFloat(src.P.X, 'f', -1, 64),
strconv.FormatFloat(src.P.Y, 'f', -1, 64),
)...), nil
}
func (src Point) EncodeBinary(ci *ConnInfo, buf []byte) ([]byte, error) {
switch src.Status {
case Null:
return nil, nil
case Undefined:
return nil, errUndefined
}
buf = pgio.AppendUint64(buf, math.Float64bits(src.P.X))
buf = pgio.AppendUint64(buf, math.Float64bits(src.P.Y))
return buf, nil
}
// Scan implements the database/sql Scanner interface.
func (dst *Point) Scan(src interface{}) error {
if src == nil {
*dst = Point{Status: Null}
return nil
}
switch src := src.(type) {
case string:
return dst.DecodeText(nil, []byte(src))
case []byte:
srcCopy := make([]byte, len(src))
copy(srcCopy, src)
return dst.DecodeText(nil, srcCopy)
}
return fmt.Errorf("cannot scan %T", src)
}
// Value implements the database/sql/driver Valuer interface.
func (src Point) Value() (driver.Value, error) {
return EncodeValueText(src)
}
func (src Point) MarshalJSON() ([]byte, error) {
switch src.Status {
case Present:
var buff bytes.Buffer
buff.WriteByte('"')
buff.WriteString(fmt.Sprintf("(%g,%g)", src.P.X, src.P.Y))
buff.WriteByte('"')
return buff.Bytes(), nil
case Null:
return []byte("null"), nil
case Undefined:
return nil, errUndefined
}
return nil, errBadStatus
}
func (dst *Point) UnmarshalJSON(point []byte) error {
p, err := parsePoint(point)
if err != nil {
return err
}
*dst = *p
return nil
}