From c2b237f19665ff482a2948d0afe9db54a0197f11 Mon Sep 17 00:00:00 2001
From: Andrew Steinborn <git@steinborn.me>
Date: Tue, 7 Jun 2022 23:35:43 -0400
Subject: [PATCH] DRY - one function to create respawn packets from JoinGame
 packets

---
 .../client/ClientPlaySessionHandler.java      | 26 ++++++-------------
 .../proxy/protocol/packet/Respawn.java        |  7 +++++
 2 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java b/proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java
index b65d413de..04bfd100e 100644
--- a/proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java
+++ b/proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java
@@ -525,7 +525,8 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
     // Most notably, by having the client accept the join game packet, we can work around the need
     // to perform entity ID rewrites, eliminating potential issues from rewriting packets and
     // improving compatibility with mods.
-    int sentOldDim = joinGame.getDimension();
+    final Respawn respawn = Respawn.fromJoinGame(joinGame);
+
     if (player.getProtocolVersion().compareTo(MINECRAFT_1_16) < 0) {
       // Before Minecraft 1.16, we could not switch to the same dimension without sending an
       // additional respawn. On older versions of Minecraft this forces the client to perform
@@ -533,12 +534,7 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
       joinGame.setDimension(joinGame.getDimension() == 0 ? -1 : 0);
     }
     player.getConnection().delayedWrite(joinGame);
-
-    player.getConnection().delayedWrite(
-        new Respawn(sentOldDim, joinGame.getPartialHashedSeed(),
-            joinGame.getDifficulty(), joinGame.getGamemode(), joinGame.getLevelType(),
-            false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode(),
-            joinGame.getCurrentDimensionData(), joinGame.getLastDeathPosition()));
+    player.getConnection().delayedWrite(respawn);
   }
 
   private void doSafeClientServerSwitch(JoinGame joinGame) {
@@ -550,19 +546,13 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
     player.getConnection().delayedWrite(joinGame);
 
     // Send a respawn packet in a different dimension.
-    int tempDim = joinGame.getDimension() == 0 ? -1 : 0;
-    player.getConnection().delayedWrite(
-        new Respawn(tempDim, joinGame.getPartialHashedSeed(), joinGame.getDifficulty(),
-            joinGame.getGamemode(), joinGame.getLevelType(),
-            false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode(),
-            joinGame.getCurrentDimensionData(), joinGame.getLastDeathPosition()));
+    final Respawn fakeSwitchPacket = Respawn.fromJoinGame(joinGame);
+    fakeSwitchPacket.setDimension(joinGame.getDimension() == 0 ? -1 : 0);
+    player.getConnection().delayedWrite(fakeSwitchPacket);
 
     // Now send a respawn packet in the correct dimension.
-    player.getConnection().delayedWrite(
-        new Respawn(joinGame.getDimension(), joinGame.getPartialHashedSeed(),
-            joinGame.getDifficulty(), joinGame.getGamemode(), joinGame.getLevelType(),
-            false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode(),
-            joinGame.getCurrentDimensionData(), joinGame.getLastDeathPosition()));
+    final Respawn correctSwitchPacket = Respawn.fromJoinGame(joinGame);
+    player.getConnection().delayedWrite(correctSwitchPacket);
   }
 
   public List<UUID> getServerBossBars() {
diff --git a/proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Respawn.java b/proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Respawn.java
index e5db58bba..fc2d42e0c 100644
--- a/proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Respawn.java
+++ b/proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Respawn.java
@@ -60,6 +60,13 @@ public class Respawn implements MinecraftPacket {
     this.lastDeathPosition = lastDeathPosition;
   }
 
+  public static Respawn fromJoinGame(JoinGame joinGame) {
+    return new Respawn(joinGame.getDimension(), joinGame.getPartialHashedSeed(),
+        joinGame.getDifficulty(), joinGame.getGamemode(), joinGame.getLevelType(),
+        false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode(),
+        joinGame.getCurrentDimensionData(), joinGame.getLastDeathPosition());
+  }
+
   public int getDimension() {
     return dimension;
   }