105 lines
2.2 KiB
Go
105 lines
2.2 KiB
Go
package main
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"encoding/json"
|
|
"fmt"
|
|
"io"
|
|
)
|
|
|
|
const (
|
|
RemoteGetState = uint16(0x01)
|
|
RemoteHandleMessage = uint16(0x02)
|
|
ResponseBody = uint16(0x03)
|
|
)
|
|
|
|
type CartPacket struct {
|
|
Version uint16
|
|
MessageType uint16
|
|
Id CartId
|
|
DataLength uint16
|
|
}
|
|
|
|
type Packet struct {
|
|
Version uint16
|
|
MessageType uint16
|
|
DataLength uint16
|
|
}
|
|
|
|
func SendCartPacket(conn io.Writer, id CartId, messageType uint16, datafn func(w io.Writer) error) error {
|
|
data, err := GetData(datafn)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if conn == nil {
|
|
return fmt.Errorf("no connection to send to")
|
|
}
|
|
binary.Write(conn, binary.LittleEndian, CartPacket{
|
|
Version: 2,
|
|
MessageType: messageType,
|
|
Id: id,
|
|
DataLength: uint16(len(data)),
|
|
})
|
|
_, err = conn.Write(data)
|
|
return err
|
|
}
|
|
|
|
func SendPacket(conn io.Writer, messageType uint16, datafn func(w io.Writer) error) error {
|
|
data, err := GetData(datafn)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
err = binary.Write(conn, binary.LittleEndian, Packet{
|
|
Version: 1,
|
|
MessageType: messageType,
|
|
DataLength: uint16(len(data)),
|
|
})
|
|
if err != nil {
|
|
return err
|
|
}
|
|
packetsSent.Inc()
|
|
_, err = conn.Write(data)
|
|
return err
|
|
}
|
|
|
|
func SendRawResponse(conn io.Writer, data []byte) error {
|
|
err := binary.Write(conn, binary.LittleEndian, Packet{
|
|
Version: 1,
|
|
MessageType: ResponseBody,
|
|
DataLength: uint16(len(data)),
|
|
})
|
|
if err != nil {
|
|
return err
|
|
}
|
|
_, err = conn.Write(data)
|
|
return err
|
|
}
|
|
|
|
func SendProxyResponse(conn io.Writer, data any) error {
|
|
return SendPacket(conn, ResponseBody, func(w io.Writer) error {
|
|
data, err := json.Marshal(data)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
w.Write(data)
|
|
return nil
|
|
})
|
|
}
|
|
|
|
func ReceivePacket(conn io.Reader) (uint16, []byte, error) {
|
|
var packet Packet
|
|
err := binary.Read(conn, binary.LittleEndian, &packet)
|
|
if err != nil {
|
|
return packet.MessageType, nil, err
|
|
}
|
|
data := make([]byte, packet.DataLength)
|
|
l, err := conn.Read(data)
|
|
if err != nil {
|
|
return packet.MessageType, nil, err
|
|
}
|
|
if l != int(packet.DataLength) {
|
|
return packet.MessageType, nil, fmt.Errorf("expected %d bytes, got %d", packet.DataLength, l)
|
|
}
|
|
return packet.MessageType, data, nil
|
|
}
|