From 285b2a9dad3495fe97e1aab5b7c960fe7f06724a Mon Sep 17 00:00:00 2001
From: Rika <40230165+Moreonenight@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:16:36 +0800
Subject: [PATCH] Fix /back bug

Fix server crash on /back command if teleporting to a dimension add by mods.
---
 .../vanilla/commands/TeleportCommand.java     | 23 +++++++++++++++----
 .../core/impl/commands/BackLocationCommand.kt | 20 ++++++++++++----
 2 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/src/main/java/com/mairwunnx/projectessentials/core/impl/vanilla/commands/TeleportCommand.java b/src/main/java/com/mairwunnx/projectessentials/core/impl/vanilla/commands/TeleportCommand.java
index 7b5472d..4eac1bd 100644
--- a/src/main/java/com/mairwunnx/projectessentials/core/impl/vanilla/commands/TeleportCommand.java
+++ b/src/main/java/com/mairwunnx/projectessentials/core/impl/vanilla/commands/TeleportCommand.java
@@ -26,12 +26,15 @@
 import net.minecraft.world.server.ServerWorld;
 import net.minecraft.world.server.TicketType;
 import org.jetbrains.annotations.NotNull;
+import net.minecraftforge.common.util.ITeleporter;
+import net.minecraft.world.dimension.DimensionType;
 
 import javax.annotation.Nullable;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.EnumSet;
 import java.util.Set;
+import java.util.function.Function;
 
 public class TeleportCommand extends VanillaCommandBase {
     public TeleportCommand() {
@@ -116,6 +119,18 @@ private static int teleportToPos(CommandSource source, Collection<? extends Enti
         return targets.size();
     }
 
+    public static void changeDimension(Entity entityIn, ServerWorld worldIn) {
+        ((ServerPlayerEntity) entityIn).changeDimension(worldIn.getDimension().getType() , new ITeleporter()
+        {
+            @Override
+            public Entity placeEntity(Entity entity, ServerWorld currentWorld, ServerWorld destWorld, float yaw, Function<Boolean, Entity> repositionEntity)
+            {
+                Entity repositionedEntity = repositionEntity.apply(false);
+                return repositionedEntity;
+            }
+        });    
+    }
+
     public static void teleport(CommandSource source, Entity entityIn, ServerWorld worldIn, double x, double y, double z, Set<SPlayerPositionLookPacket.Flags> relativeList, float yaw, float pitch, @Nullable Facing facing) {
         if (entityIn instanceof ServerPlayerEntity) {
             ChunkPos chunkpos = new ChunkPos(new BlockPos(x, y, z));
@@ -125,12 +140,10 @@ public static void teleport(CommandSource source, Entity entityIn, ServerWorld w
                 ((ServerPlayerEntity) entityIn).stopSleepInBed(true, true);
             }
 
-            if (worldIn == entityIn.world) {
-                ((ServerPlayerEntity) entityIn).connection.setPlayerLocation(x, y, z, yaw, pitch, relativeList);
-            } else {
-                ((ServerPlayerEntity) entityIn).teleport(worldIn, x, y, z, yaw, pitch);
+            if (worldIn != entityIn.world) {
+                changeDimension(entityIn, worldIn);
             }
-
+            ((ServerPlayerEntity) entityIn).connection.setPlayerLocation(x, y, z, yaw, pitch, relativeList);
             entityIn.setRotationYawHead(yaw);
         } else {
             float f1 = MathHelper.wrapDegrees(yaw);
diff --git a/src/main/kotlin/com/mairwunnx/projectessentials/core/impl/commands/BackLocationCommand.kt b/src/main/kotlin/com/mairwunnx/projectessentials/core/impl/commands/BackLocationCommand.kt
index 5fee581..6daa219 100644
--- a/src/main/kotlin/com/mairwunnx/projectessentials/core/impl/commands/BackLocationCommand.kt
+++ b/src/main/kotlin/com/mairwunnx/projectessentials/core/impl/commands/BackLocationCommand.kt
@@ -2,6 +2,7 @@ package com.mairwunnx.projectessentials.core.impl.commands
 
 import com.mairwunnx.projectessentials.core.api.v1.MESSAGE_CORE_PREFIX
 import com.mairwunnx.projectessentials.core.api.v1.commands.CommandBase
+import com.mairwunnx.projectessentials.core.impl.vanilla.commands.TeleportCommand
 import com.mairwunnx.projectessentials.core.api.v1.commands.back.BackLocationAPI
 import com.mairwunnx.projectessentials.core.api.v1.extensions.getPlayer
 import com.mairwunnx.projectessentials.core.api.v1.extensions.isPlayerSender
@@ -10,7 +11,11 @@ import com.mairwunnx.projectessentials.core.api.v1.messaging.ServerMessagingAPI
 import com.mairwunnx.projectessentials.core.api.v1.permissions.hasPermission
 import com.mojang.brigadier.builder.LiteralArgumentBuilder.literal
 import com.mojang.brigadier.context.CommandContext
+import net.minecraft.world.server.TicketType
+import net.minecraft.entity.player.ServerPlayerEntity
 import net.minecraft.command.CommandSource
+import net.minecraft.util.math.ChunkPos
+import net.minecraft.util.math.BlockPos
 
 internal object BackLocationCommand : CommandBase(literal("back")) {
     override val name = "back"
@@ -28,11 +33,16 @@ internal object BackLocationCommand : CommandBase(literal("back")) {
                 if (data != null) {
                     val pos = data.position
                     val rot = data.rotation
-
-                    player.teleport(
-                        data.world, pos.xPos, pos.yPos, pos.zPos, rot.yaw, rot.pitch
-                    )
-
+                    val chunkpos = ChunkPos(BlockPos(pos.xPos, pos.yPos, pos.zPos))
+                    data.world.getChunkProvider().registerTicket(TicketType.POST_TELEPORT, chunkpos, 1, player.getEntityId())
+                    player.stopRiding()
+                    if (player.isSleeping()) {
+                        player.stopSleepInBed(true, true)
+                    }
+                    if (data.world != player.serverWorld) {
+                        TeleportCommand.changeDimension(player, data.world)
+                    }
+                    player.connection.setPlayerLocation(pos.xPos, pos.yPos, pos.zPos, rot.yaw, rot.pitch)
                     BackLocationAPI.revoke(player)
                     MessagingAPI.sendMessage(player, "$MESSAGE_CORE_PREFIX.back.success")
                 } else {