strom: add 1.12.2 protocol support and legacy login/status handlers

- Add minecraft-data for 1.12.2 (protocol 340)
- Generate proto_generated/v1_12_2
- Add v1_12_2 legacy handlers to client.Login (OnDisconnect,
  OnCompress, OnSuccess) and client.Status (OnStatus, OnPong)
- Same pattern as v1_8: RegisterUntilLatest only registers
  upward, so legacy versions need explicit RegisterCritical handlers

mc/client/login.go

@@ -16,6 +16,7 @@ import (
 	"github.com/admin-else/strom/mc/proto_base"
 	"github.com/admin-else/strom/mc/proto_generated/v1_21_8"
 	"github.com/admin-else/strom/mc/proto_generated/v1_8"
+	"github.com/admin-else/strom/mc/proto_generated/v1_12_2"
 	"github.com/admin-else/strom/mc/proto_generated/v26_2"
 	"github.com/admin-else/strom/mc/text"
 	"github.com/google/uuid"
@@ -139,6 +140,31 @@ func (s *LoginClient) OnSuccessV1_8(success *v1_8.LoginToClientPacketSuccess) (e
 	return
 }
 
+func (s *LoginClient) OnDisconnectV1_12_2(packet *v1_12_2.LoginToClientPacketDisconnect) (err error) {
+	var reason text.Component
+	err = json.Unmarshal([]byte(packet.Reason), &reason)
+	if err != nil {
+		return
+	}
+	err = KickedDuringLoginErr{reason}
+	return
+}
+
+func (s *LoginClient) OnCompressV1_12_2(packet *v1_12_2.LoginToClientPacketCompress) (err error) {
+	s.SetCompressionThreshold(packet.Threshold)
+	return
+}
+
+func (s *LoginClient) OnSuccessV1_12_2(success *v1_12_2.LoginToClientPacketSuccess) (err error) {
+	s.GivenAccount = &v1_21_8.LoginToClientPacketSuccess{
+		Uuid:     uuid.MustParse(success.Uuid),
+		Username: success.Username,
+	}
+	s.SetState(proto_base.Play)
+	err = event.HandlerDoneErr{}
+	return
+}
+
 func (s *LoginClient) OnSuccess(success *v1_21_8.LoginToClientPacketSuccess) (err error) {
 	s.GivenAccount = success
 	if s.ProtocolVersion >= 764 {
@@ -189,6 +215,9 @@ func LoginRawAddr(c *proto.Conn, account *api.Account, hostAddr string) (err err
 	lc.RegisterCritical(lc.OnCompressV1_8)
 	lc.RegisterCritical(lc.OnDisconnectV1_8)
 	lc.RegisterCritical(lc.OnSuccessV1_8)
+	lc.RegisterCritical(lc.OnCompressV1_12_2)
+	lc.RegisterCritical(lc.OnDisconnectV1_12_2)
+	lc.RegisterCritical(lc.OnSuccessV1_12_2)
 
 	var p proto_base.EncodeDecodeAble
 	if hostAddr != "" {

mc/client/status.go

@@ -10,6 +10,7 @@ import (
 	"github.com/admin-else/strom/mc/proto_base"
 	"github.com/admin-else/strom/mc/proto_generated/v1_21_8"
 	"github.com/admin-else/strom/mc/proto_generated/v1_8"
+	"github.com/admin-else/strom/mc/proto_generated/v1_12_2"
 	"github.com/admin-else/strom/mc/server"
 )
 
@@ -54,6 +55,23 @@ func (s *StatusClient) OnPongV1_8(p *v1_8.StatusToClientPacketPing) (err error)
 	return
 }
 
+func (s *StatusClient) OnStatusV1_12_2(p *v1_12_2.StatusToClientPacketServerInfo) (err error) {
+	s.Status = p.Response
+	s.PingSendTime = time.Now()
+	if s.DoPingRoundTripTime {
+		err = s.Send(&v1_21_8.StatusToServerPacketPing{Time: s.PingSendTime.UnixMilli()})
+	} else {
+		err = event.HandlerDoneErr{}
+	}
+	return
+}
+
+func (s *StatusClient) OnPongV1_12_2(p *v1_12_2.StatusToClientPacketPing) (err error) {
+	s.PingReceiveTime = time.Now()
+	err = event.HandlerDoneErr{}
+	return
+}
+
 // StatusRaw returns a StatusClient that is not connected to a server.
 // So ignore the resource leak warning. And maybe attach a warn ignore comment.
 // It does not resolve SRV records.
@@ -79,6 +97,8 @@ func StatusRawWithVersion(ctx context.Context, addr, version string) (s *StatusC
 	s.RegisterCriticalUntilLatest(s.OnPong)
 	s.RegisterCritical(s.OnStatusV1_8)
 	s.RegisterCritical(s.OnPongV1_8)
+	s.RegisterCritical(s.OnStatusV1_12_2)
+	s.RegisterCritical(s.OnPongV1_12_2)
 
 	p, err := MakeHandshakePacketAddr(s.Conn, proto_base.Status, addr)
 	if err != nil {

mc/data/minecraft-data/pc/1.12.2/version.json

@@ -0,0 +1,5 @@
+{
+  "minecraftVersion": "1.12.2",
+  "version":340,
+  "majorVersion": "1.12"
+}

mc/proto_generator/main.go

@@ -429,7 +429,7 @@ func GenerateVersions(versions []string) (err error) {
 }
 
 func main() {
-	err := GenerateVersions([]string{"1.8", "1.21.8", "1.21.9", "1.21.11", "26.1", "26.2"})
+	err := GenerateVersions([]string{"1.8", "1.12.2", "1.21.8", "1.21.9", "1.21.11", "26.1", "26.2"})
 	if err != nil {
 		panic(err)
 	}