Feature: Allow client-side "game settings" menu gamemode/difficulty changes

bootstrap/fabric/src/main/java/org/geysermc/geyser/platform/fabric/world/GeyserFabricWorldManager.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.geyser.platform.fabric.world;
 
+import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
 import com.github.steveice10.mc.protocol.data.game.level.block.BlockEntityInfo;
 import me.lucko.fabric.api.permissions.v0.Permissions;
 import net.minecraft.core.BlockPos;
@@ -153,6 +154,11 @@ public boolean hasPermission(GeyserSession session, String permission) {
         return Permissions.check(player, permission);
     }
 
+    @Override
+    public GameMode getDefaultGameMode(GeyserSession session) {
+        return GameMode.byId(server.getDefaultGameType().getId());
+    }
+
     @Nonnull
     @Override
     public CompletableFuture<com.github.steveice10.opennbt.tag.builtin.CompoundTag> getPickItemNbt(GeyserSession session, int x, int y, int z, boolean addNbtData) {

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/world/manager/GeyserSpigotWorldManager.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.geyser.platform.spigot.world.manager;
 
+import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
 import com.github.steveice10.mc.protocol.data.game.level.block.BlockEntityInfo;
 import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import org.bukkit.Bukkit;
@@ -171,6 +172,11 @@ public int getGameRuleInt(GeyserSession session, GameRule gameRule) {
         return gameRule.getDefaultIntValue();
     }
 
+    @Override
+    public GameMode getDefaultGameMode(GeyserSession session) {
+        return GameMode.byId(Bukkit.getDefaultGameMode().ordinal());
+    }
+
     @Override
     public boolean hasPermission(GeyserSession session, String permission) {
         return Bukkit.getPlayer(session.getPlayerEntity().getUsername()).hasPermission(permission);

core/src/main/java/org/geysermc/geyser/level/GeyserWorldManager.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.geyser.level;
 
+import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
 import com.github.steveice10.mc.protocol.data.game.level.block.BlockEntityInfo;
 import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import it.unimi.dsi.fastutil.objects.Object2ObjectMap;
@@ -160,6 +161,11 @@ public int getGameRuleInt(GeyserSession session, GameRule gameRule) {
         return gameRule.getDefaultIntValue();
     }
 
+    @Override
+    public GameMode getDefaultGameMode(GeyserSession session) {
+        return GameMode.SURVIVAL;
+    }
+
     @Override
     public boolean hasPermission(GeyserSession session, String permission) {
         return false;

core/src/main/java/org/geysermc/geyser/level/WorldManager.java

@@ -170,6 +170,24 @@ public void setPlayerGameMode(GeyserSession session, GameMode gameMode) {
         session.sendCommand("gamemode " + gameMode.name().toLowerCase(Locale.ROOT));
     }
 
+    /**
+     * Get the default game mode of the server
+     *
+     * @param session The session of the player requesting the default game mode
+     * @return The default game mode of the server, or Survival if unknown.
+     */
+    public abstract GameMode getDefaultGameMode(GeyserSession session);
+
+    /**
+     * Change the default game mode of the session's server
+     *
+     * @param session The session of the player making the change
+     * @param gameMode The new default game mode
+     */
+    public void setDefaultGameMode(GeyserSession session, GameMode gameMode) {
+        session.sendCommand("defaultgamemode " + gameMode.name().toLowerCase(Locale.ROOT));
+    }
+
     /**
      * Change the difficulty of the Java server
      *

core/src/main/java/org/geysermc/geyser/network/LoggingPacketHandler.java

@@ -255,6 +255,11 @@ public PacketSignal handle(RequestChunkRadiusPacket packet) {
         return defaultHandler(packet);
     }
 
+    @Override
+    public PacketSignal handle(RequestPermissionsPacket packet) {
+        return defaultHandler(packet);
+    }
+
     @Override
     public PacketSignal handle(ResourcePackChunkRequestPacket packet) {
         return defaultHandler(packet);

core/src/main/java/org/geysermc/geyser/registry/PacketTranslatorRegistry.java

@@ -29,6 +29,7 @@
 import com.github.steveice10.mc.protocol.packet.ingame.clientbound.ClientboundTabListPacket;
 import com.github.steveice10.mc.protocol.packet.ingame.clientbound.level.ClientboundLightUpdatePacket;
 import io.netty.channel.EventLoop;
+import org.cloudburstmc.protocol.bedrock.packet.RequestPermissionsPacket;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.registry.loader.RegistryLoaders;
 import org.geysermc.geyser.session.GeyserSession;
@@ -46,6 +47,7 @@ public class PacketTranslatorRegistry<T> extends AbstractMappedRegistry<Class<?
         IGNORED_PACKETS.add(ClientboundLightUpdatePacket.class); // Light is handled on Bedrock for us
         IGNORED_PACKETS.add(ClientboundTabListPacket.class); // Cant be implemented in Bedrock
         IGNORED_PACKETS.add(ClientboundDelimiterPacket.class); // Not implemented, spams logs
+        IGNORED_PACKETS.add(RequestPermissionsPacket.class); // Bedrock client asks permission to switch default game mode, but we handle this ourselves
     }
 
     protected PacketTranslatorRegistry() {

core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockSetDefaultGameTypeTranslator.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2019-2023 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.geyser.translator.protocol.bedrock.entity.player;
+
+import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
+import org.cloudburstmc.protocol.bedrock.packet.SetDefaultGameTypePacket;
+import org.cloudburstmc.protocol.bedrock.packet.SetPlayerGameTypePacket;
+import org.geysermc.geyser.session.GeyserSession;
+import org.geysermc.geyser.translator.protocol.PacketTranslator;
+import org.geysermc.geyser.translator.protocol.Translator;
+import org.geysermc.geyser.util.EntityUtils;
+
+@Translator(packet = SetDefaultGameTypePacket.class)
+public class BedrockSetDefaultGameTypeTranslator extends PacketTranslator<SetDefaultGameTypePacket> {
+
+    /**
+     * Sets the default game mode for the server via the Bedrock client's "world" menu (given sufficient permissions).
+     */
+    @Override
+    public void translate(GeyserSession session, SetDefaultGameTypePacket packet) {
+        if (session.getOpPermissionLevel() >= 2 || session.hasPermission("geyser.settings.server")) {
+            session.getGeyser().getWorldManager().setDefaultGameMode(session, GameMode.byId(packet.getGamemode()));
+        }
+        // Stop the client from updating their own Gamemode without telling the server
+        // Can occur when client Gamemode is set to "default", and default game mode is changed.
+        SetPlayerGameTypePacket playerGameTypePacket = new SetPlayerGameTypePacket();
+        playerGameTypePacket.setGamemode(EntityUtils.toBedrockGamemode(session.getGameMode()).ordinal());
+        session.sendUpstreamPacket(playerGameTypePacket);
+    }
+}

core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockSetDifficultyTranslator.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2019-2023 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.geyser.translator.protocol.bedrock.entity.player;
+
+import com.github.steveice10.mc.protocol.data.game.setting.Difficulty;
+import org.cloudburstmc.protocol.bedrock.packet.SetDifficultyPacket;
+import org.geysermc.geyser.session.GeyserSession;
+import org.geysermc.geyser.translator.protocol.PacketTranslator;
+import org.geysermc.geyser.translator.protocol.Translator;
+
+@Translator(packet = SetDifficultyPacket.class)
+public class BedrockSetDifficultyTranslator extends PacketTranslator<SetDifficultyPacket> {
+
+    /**
+     * Sets the Java server's difficulty via the Bedrock client's "world" menu (given sufficient permissions).
+     */
+    @Override
+    public void translate(GeyserSession session, SetDifficultyPacket packet) {
+        if (session.getOpPermissionLevel() >= 2 || session.hasPermission("geyser.settings.server")) {
+            if (packet.getDifficulty() != session.getWorldCache().getDifficulty().ordinal()) {
+                session.getGeyser().getWorldManager().setDifficulty(session, Difficulty.from(packet.getDifficulty()));
+            }
+        }
+    }
+}

core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockSetPlayerGameTypeTranslator.java

@@ -25,23 +25,43 @@
 
 package org.geysermc.geyser.translator.protocol.bedrock.entity.player;
 
+import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
 import org.cloudburstmc.protocol.bedrock.packet.SetPlayerGameTypePacket;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.protocol.PacketTranslator;
 import org.geysermc.geyser.translator.protocol.Translator;
+import org.geysermc.geyser.util.EntityUtils;
 
 /**
  * In vanilla Bedrock, if you have operator status, this sets the player's gamemode without confirmation from the server.
- * Since we have a custom server option to request the gamemode, we just reset the gamemode and ignore this.
+ * With operator status, the Gamemode change is sent to the Java server, if it is not present, the gamemode is not changed.
  */
 @Translator(packet = SetPlayerGameTypePacket.class)
 public class BedrockSetPlayerGameTypeTranslator extends PacketTranslator<SetPlayerGameTypePacket> {
 
+    /**
+     * Sets client game mode for the server via the Bedrock client's "world" menu (given sufficient permissions).
+     */
     @Override
     public void translate(GeyserSession session, SetPlayerGameTypePacket packet) {
-        // no
-        SetPlayerGameTypePacket playerGameTypePacket = new SetPlayerGameTypePacket();
-        playerGameTypePacket.setGamemode(session.getGameMode().ordinal());
-        session.sendUpstreamPacket(playerGameTypePacket);
+        // yes, if you are OP
+        if (session.getOpPermissionLevel() >= 2 || session.hasPermission("geyser.settings.server")) {
+            if (packet.getGamemode() != session.getGameMode().ordinal()) {
+                // Bedrock has more Gamemodes than Java, leading to cases 5 (for "default") and 6 (for "spectator") being sent
+                // https://github.com/CloudburstMC/Protocol/blob/3.0/bedrock-codec/src/main/java/org/cloudburstmc/protocol/bedrock/data/GameType.java
+                GameMode gameMode = switch (packet.getGamemode()) {
+                    case 1 -> GameMode.CREATIVE;
+                    case 2 -> GameMode.ADVENTURE;
+                    case 5 -> session.getGeyser().getWorldManager().getDefaultGameMode(session);
+                    case 6 -> GameMode.SPECTATOR;
+                    default -> GameMode.SURVIVAL;
+                };
+                session.getGeyser().getWorldManager().setPlayerGameMode(session, gameMode);
+            }
+        } else {
+            SetPlayerGameTypePacket playerGameTypePacket = new SetPlayerGameTypePacket();
+            playerGameTypePacket.setGamemode(EntityUtils.toBedrockGamemode(session.getGameMode()).ordinal());
+            session.sendUpstreamPacket(playerGameTypePacket);
+        }
     }
 }

core/src/main/java/org/geysermc/geyser/util/SettingsUtils.java

@@ -25,8 +25,6 @@
 
 package org.geysermc.geyser.util;
 
-import com.github.steveice10.mc.protocol.data.game.entity.player.GameMode;
-import com.github.steveice10.mc.protocol.data.game.setting.Difficulty;
 import org.geysermc.cumulus.component.DropdownComponent;
 import org.geysermc.cumulus.form.CustomForm;
 import org.geysermc.geyser.GeyserImpl;
@@ -77,23 +75,6 @@ public static CustomForm buildForm(GeyserSession session) {
             }
         }
 
-        boolean canModifyServer = session.getOpPermissionLevel() >= 2 || session.hasPermission("geyser.settings.server");
-        if (canModifyServer) {
-            builder.label("geyser.settings.title.server");
-
-            DropdownComponent.Builder gamemodeDropdown = DropdownComponent.builder("%createWorldScreen.gameMode.personal");
-            for (GameMode gamemode : GameMode.values()) {
-                gamemodeDropdown.option("selectWorld.gameMode." + gamemode.name().toLowerCase(), session.getGameMode() == gamemode);
-            }
-            builder.dropdown(gamemodeDropdown);
-
-            DropdownComponent.Builder difficultyDropdown = DropdownComponent.builder("%options.difficulty");
-            for (Difficulty difficulty : Difficulty.values()) {
-                difficultyDropdown.option("%options.difficulty." + difficulty.name().toLowerCase(), session.getWorldCache().getDifficulty() == difficulty);
-            }
-            builder.dropdown(difficultyDropdown);
-        }
-
         boolean showGamerules = session.getOpPermissionLevel() >= 2 || session.hasPermission("geyser.settings.gamerules");
         if (showGamerules) {
             builder.label("geyser.settings.title.game_rules")
@@ -128,18 +109,6 @@ public static CustomForm buildForm(GeyserSession session) {
                 }
             }
 
-            if (canModifyServer) {
-                GameMode gameMode = GameMode.values()[(int) response.next()];
-                if (gameMode != null && gameMode != session.getGameMode()) {
-                    session.getGeyser().getWorldManager().setPlayerGameMode(session, gameMode);
-                }
-
-                Difficulty difficulty = Difficulty.values()[(int) response.next()];
-                if (difficulty != null && difficulty != session.getWorldCache().getDifficulty()) {
-                    session.getGeyser().getWorldManager().setDifficulty(session, difficulty);
-                }
-            }
-
             if (showGamerules) {
                 for (GameRule gamerule : GameRule.VALUES) {
                     if (Boolean.class.equals(gamerule.getType())) {