Handle legacy server list ping for handshake

mcproto/types.go

@@ -7,6 +7,12 @@ type Frame struct {
 	Payload []byte
 }
 
+type State int
+
+const (
+	StateHandshaking = iota
+)
+
 var trimLimit = 64
 
 func trimBytes(data []byte) ([]byte, string) {
@@ -25,15 +31,23 @@ func (f *Frame) String() string {
 type Packet struct {
 	Length   int
 	PacketID int
-	Data     []byte
+	// Data is either a byte slice of raw content or a parsed message
+	Data interface{}
 }
 
 func (p *Packet) String() string {
-	trimmed, cont := trimBytes(p.Data)
-	return fmt.Sprintf("Frame:[len=%d, packetId=%d, data=%#X%s]", p.Length, p.PacketID, trimmed, cont)
+	if dataBytes, ok := p.Data.([]byte); ok {
+		trimmed, cont := trimBytes(dataBytes)
+		return fmt.Sprintf("Frame:[len=%d, packetId=%d, data=%#X%s]", p.Length, p.PacketID, trimmed, cont)
+	} else {
+		return fmt.Sprintf("Frame:[len=%d, packetId=%d, data=%+v]", p.Length, p.PacketID, p.Data)
+	}
 }
 
-const PacketIdHandshake = 0x00
+const (
+	PacketIdHandshake            = 0x00
+	PacketIdLegacyServerListPing = 0xFE
+)
 
 type Handshake struct {
 	ProtocolVersion int
@@ -42,6 +56,12 @@ type Handshake struct {
 	NextState       int
 }
 
+type LegacyServerListPing struct {
+	ProtocolVersion int
+	ServerAddress   string
+	ServerPort      uint16
+}
+
 type ByteReader interface {
 	ReadByte() (byte, error)
 }