Fix ACCEPT_TELEPORTATION packet order (#11)

common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/Protocol1_21To1_21_2.java

@@ -46,6 +46,8 @@ import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ServerboundPacke
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.rewriter.BlockItemPacketRewriter1_21_2;
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.rewriter.ComponentRewriter1_21_2;
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.rewriter.EntityPacketRewriter1_21_2;
+import com.viaversion.viaversion.protocols.v1_21to1_21_2.storage.BundleStateTracker;
+import com.viaversion.viaversion.protocols.v1_21to1_21_2.storage.PlayerPositionStorage;
 import com.viaversion.viaversion.rewriter.AttributeRewriter;
 import com.viaversion.viaversion.rewriter.SoundRewriter;
 import com.viaversion.viaversion.rewriter.StatisticsRewriter;
@@ -159,6 +161,14 @@ public final class Protocol1_21To1_21_2 extends AbstractProtocol<ClientboundPack
                 componentRewriter.processTag(wrapper.user(), wrapper.passthrough(Types.OPTIONAL_TAG));
             }
         });
+
+        registerClientbound(ClientboundPackets1_21.BUNDLE_DELIMITER, wrapper -> wrapper.user().get(BundleStateTracker.class).toggleBundling());
+        registerServerbound(ServerboundPackets1_21_2.PONG, wrapper -> {
+            final int id = wrapper.passthrough(Types.INT); // id
+            if (wrapper.user().get(PlayerPositionStorage.class).checkPong(id)) {
+                wrapper.cancel();
+            }
+        });
     }
 
     private void clientInformation(final PacketWrapper wrapper) {
@@ -215,6 +225,8 @@ public final class Protocol1_21To1_21_2 extends AbstractProtocol<ClientboundPack
     @Override
     public void init(final UserConnection connection) {
         addEntityTracker(connection, new EntityTrackerBase(connection, EntityTypes1_21_2.PLAYER));
+        connection.put(new BundleStateTracker());
+        connection.put(new PlayerPositionStorage());
     }
 
     @Override

common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/rewriter/EntityPacketRewriter1_21_2.java

@@ -32,9 +32,12 @@ import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPacke
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.Protocol1_21To1_21_2;
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ClientboundPackets1_21_2;
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.packet.ServerboundPackets1_21_2;
+import com.viaversion.viaversion.protocols.v1_21to1_21_2.storage.BundleStateTracker;
 import com.viaversion.viaversion.protocols.v1_21to1_21_2.storage.ClientVehicleStorage;
+import com.viaversion.viaversion.protocols.v1_21to1_21_2.storage.PlayerPositionStorage;
 import com.viaversion.viaversion.rewriter.EntityRewriter;
 import com.viaversion.viaversion.rewriter.RegistryDataRewriter;
+import java.util.concurrent.ThreadLocalRandom;
 
 public final class EntityPacketRewriter1_21_2 extends EntityRewriter<ClientboundPacket1_21, Protocol1_21To1_21_2> {
 
@@ -151,6 +154,27 @@ public final class EntityPacketRewriter1_21_2 extends EntityRewriter<Clientbound
 
             final int teleportId = wrapper.read(Types.VAR_INT);
             wrapper.set(Types.VAR_INT, 0, teleportId);
+
+            // Accept teleportation and player position were swapped.
+            // Send a ping first to then capture and send the player position the accept teleportation
+            final boolean isBundling = wrapper.user().get(BundleStateTracker.class).isBundling();
+            if (!isBundling) {
+                final PacketWrapper bundleStart = wrapper.create(ClientboundPackets1_21_2.BUNDLE_DELIMITER);
+                bundleStart.send(Protocol1_21To1_21_2.class);
+            }
+
+            final int pingId = ThreadLocalRandom.current().nextInt();
+            wrapper.user().get(PlayerPositionStorage.class).addPendingPong(pingId);
+            final PacketWrapper ping = wrapper.create(ClientboundPackets1_21_2.PING);
+            ping.write(Types.INT, pingId); // id
+            ping.send(Protocol1_21To1_21_2.class);
+            wrapper.send(Protocol1_21To1_21_2.class);
+            wrapper.cancel();
+
+            if (!isBundling) {
+                final PacketWrapper bundleEnd = wrapper.create(ClientboundPackets1_21_2.BUNDLE_DELIMITER);
+                bundleEnd.send(Protocol1_21To1_21_2.class);
+            }
         });
 
         protocol.registerClientbound(ClientboundPackets1_21.SET_PASSENGERS, wrapper -> {
@@ -236,12 +260,20 @@ public final class EntityPacketRewriter1_21_2 extends EntityRewriter<Clientbound
             readOnGround(wrapper);
         });
         protocol.registerServerbound(ServerboundPackets1_21_2.MOVE_PLAYER_POS_ROT, wrapper -> {
-            wrapper.passthrough(Types.DOUBLE); // X
+            final double x = wrapper.passthrough(Types.DOUBLE); // X
-            wrapper.passthrough(Types.DOUBLE); // Y
+            final double y = wrapper.passthrough(Types.DOUBLE); // Y
-            wrapper.passthrough(Types.DOUBLE); // Z
+            final double z = wrapper.passthrough(Types.DOUBLE); // Z
-            wrapper.passthrough(Types.FLOAT); // Yaw
+            final float yaw = wrapper.passthrough(Types.FLOAT); // Yaw
-            wrapper.passthrough(Types.FLOAT); // Pitch
+            final float pitch = wrapper.passthrough(Types.FLOAT); // Pitch
             readOnGround(wrapper);
+
+            final PlayerPositionStorage playerPositionStorage = wrapper.user().get(PlayerPositionStorage.class);
+            if (playerPositionStorage.checkCaptureNextPlayerPositionPacket()) {
+                // Capture this packet and send it after accept teleportation
+                final boolean onGround = wrapper.get(Types.BOOLEAN, 0);
+                playerPositionStorage.setPlayerPosition(new PlayerPositionStorage.PlayerPosition(x, y, z, yaw, pitch, onGround));
+                wrapper.cancel();
+            }
         });
         protocol.registerServerbound(ServerboundPackets1_21_2.MOVE_PLAYER_ROT, wrapper -> {
             wrapper.passthrough(Types.FLOAT); // Yaw
@@ -249,6 +281,15 @@ public final class EntityPacketRewriter1_21_2 extends EntityRewriter<Clientbound
             readOnGround(wrapper);
         });
         protocol.registerServerbound(ServerboundPackets1_21_2.MOVE_PLAYER_STATUS_ONLY, this::readOnGround);
+        protocol.registerServerbound(ServerboundPackets1_21_2.ACCEPT_TELEPORTATION, wrapper -> {
+            final PlayerPositionStorage playerPositionStorage = wrapper.user().get(PlayerPositionStorage.class);
+            if (playerPositionStorage.hasPlayerPosition()) {
+                // Send move player after accept teleportation
+                wrapper.sendToServer(Protocol1_21To1_21_2.class);
+                wrapper.cancel();
+                playerPositionStorage.sendMovePlayerPosRot(wrapper.user());
+            }
+        });
     }
 
     private RegistryDataRewriter registryDataRewriter() {

common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/storage/BundleStateTracker.java

@@ -0,0 +1,34 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.protocols.v1_21to1_21_2.storage;
+
+import com.viaversion.viaversion.api.connection.StorableObject;
+
+public class BundleStateTracker implements StorableObject {
+
+    private boolean bundling;
+
+    public boolean isBundling() {
+        return this.bundling;
+    }
+
+    public void toggleBundling() {
+        this.bundling = !this.bundling;
+    }
+
+}

common/src/main/java/com/viaversion/viaversion/protocols/v1_21to1_21_2/storage/PlayerPositionStorage.java

@@ -0,0 +1,83 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.protocols.v1_21to1_21_2.storage;
+
+import com.viaversion.viaversion.api.connection.StorableObject;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundPackets1_20_5;
+import com.viaversion.viaversion.protocols.v1_21to1_21_2.Protocol1_21To1_21_2;
+import it.unimi.dsi.fastutil.ints.IntOpenHashSet;
+import it.unimi.dsi.fastutil.ints.IntSet;
+
+public class PlayerPositionStorage implements StorableObject {
+
+    private final IntSet pendingPongs = new IntOpenHashSet();
+    private boolean captureNextPlayerPositionPacket;
+    private PlayerPosition playerPosition;
+
+    public void addPendingPong(final int id) {
+        if (!this.pendingPongs.add(id)) {
+            throw new IllegalStateException("Pong already pending for id " + id);
+        }
+    }
+
+    public boolean checkPong(final int id) {
+        if (this.pendingPongs.remove(id)) {
+            this.captureNextPlayerPositionPacket = true;
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    public boolean checkCaptureNextPlayerPositionPacket() {
+        if (this.captureNextPlayerPositionPacket) {
+            this.captureNextPlayerPositionPacket = false;
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    public void setPlayerPosition(final PlayerPosition playerPosition) {
+        this.playerPosition = playerPosition;
+    }
+
+    public boolean hasPlayerPosition() {
+        return this.playerPosition != null;
+    }
+
+    public void sendMovePlayerPosRot(final UserConnection user) {
+        final PacketWrapper movePlayerPosRot = PacketWrapper.create(ServerboundPackets1_20_5.MOVE_PLAYER_POS_ROT, user);
+        movePlayerPosRot.write(Types.DOUBLE, this.playerPosition.x); // X
+        movePlayerPosRot.write(Types.DOUBLE, this.playerPosition.y); // Y
+        movePlayerPosRot.write(Types.DOUBLE, this.playerPosition.z); // Z
+        movePlayerPosRot.write(Types.FLOAT, this.playerPosition.yaw); // Yaw
+        movePlayerPosRot.write(Types.FLOAT, this.playerPosition.pitch); // Pitch
+        movePlayerPosRot.write(Types.BOOLEAN, this.playerPosition.onGround); // On Ground
+        movePlayerPosRot.sendToServer(Protocol1_21To1_21_2.class);
+        this.captureNextPlayerPositionPacket = false;
+        this.playerPosition = null;
+    }
+
+    public record PlayerPosition(double x, double y, double z, float yaw, float pitch, boolean onGround) {
+    }
+
+}