Initial happy ghast implementation

core/src/main/java/org/geysermc/geyser/entity/EntityDefinitions.java

@@ -81,6 +81,7 @@ import org.geysermc.geyser.entity.type.living.TadpoleEntity;
 import org.geysermc.geyser.entity.type.living.animal.ArmadilloEntity;
 import org.geysermc.geyser.entity.type.living.animal.AxolotlEntity;
 import org.geysermc.geyser.entity.type.living.animal.BeeEntity;
+import org.geysermc.geyser.entity.type.living.animal.HappyGhastEntity;
 import org.geysermc.geyser.entity.type.living.animal.farm.ChickenEntity;
 import org.geysermc.geyser.entity.type.living.animal.farm.CowEntity;
 import org.geysermc.geyser.entity.type.living.animal.FoxEntity;
@@ -215,6 +216,7 @@ public final class EntityDefinitions {
     public static final EntityDefinition<GlowSquidEntity> GLOW_SQUID;
     public static final EntityDefinition<GoatEntity> GOAT;
     public static final EntityDefinition<GuardianEntity> GUARDIAN;
+    public static final EntityDefinition<HappyGhastEntity> HAPPY_GHAST;
     public static final EntityDefinition<HoglinEntity> HOGLIN;
     public static final EntityDefinition<MinecartEntity> HOPPER_MINECART;
     public static final EntityDefinition<HorseEntity> HORSE;
@@ -989,6 +991,13 @@ public final class EntityDefinitions {
                     .addTranslator(MetadataTypes.FROG_VARIANT, FrogEntity::setVariant)
                     .addTranslator(MetadataTypes.OPTIONAL_UNSIGNED_INT, FrogEntity::setTongueTarget)
                     .build();
+            HAPPY_GHAST = EntityDefinition.inherited(HappyGhastEntity::new, ageableEntityBase)
+                    .type(EntityType.HAPPY_GHAST)
+                    .heightAndWidth(4f)
+                    .properties(VanillaEntityProperties.HAPPY_GHAST)
+                    .addTranslator(null) // Is leash holder
+                    .addTranslator(MetadataTypes.BOOLEAN, HappyGhastEntity::setStaysStill)
+                    .build();
             HOGLIN = EntityDefinition.inherited(HoglinEntity::new, ageableEntityBase)
                     .type(EntityType.HOGLIN)
                     .height(1.4f).width(1.3965f)

core/src/main/java/org/geysermc/geyser/entity/properties/VanillaEntityProperties.java

@@ -61,6 +61,10 @@ public class VanillaEntityProperties {
         .addInt(CreakingEntity.CREAKING_SWAYING_TICKS, 0, 6)
         .build();
 
+    public static final GeyserEntityProperties HAPPY_GHAST = new GeyserEntityProperties.Builder()
+        .addBoolean("minecraft:can_move")
+        .build();
+
     public static final GeyserEntityProperties WOLF_SOUND_VARIANT = new GeyserEntityProperties.Builder()
         .addEnum("minecraft:sound_variant",
             "default",

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/HappyGhastEntity.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2025 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.entity.type.living.animal;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.cloudburstmc.math.vector.Vector3f;
+import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
+import org.geysermc.geyser.entity.EntityDefinition;
+import org.geysermc.geyser.inventory.GeyserItemStack;
+import org.geysermc.geyser.item.type.Item;
+import org.geysermc.geyser.session.GeyserSession;
+import org.geysermc.geyser.session.cache.tags.ItemTag;
+import org.geysermc.geyser.session.cache.tags.Tag;
+import org.geysermc.geyser.util.InteractionResult;
+import org.geysermc.geyser.util.InteractiveTag;
+import org.geysermc.mcprotocollib.protocol.data.game.entity.metadata.type.BooleanEntityMetadata;
+import org.geysermc.mcprotocollib.protocol.data.game.entity.player.Hand;
+
+import java.util.UUID;
+
+public class HappyGhastEntity extends AnimalEntity {
+    public HappyGhastEntity(GeyserSession session, int entityId, long geyserId, UUID uuid, EntityDefinition<?> definition, Vector3f position, Vector3f motion, float yaw, float pitch, float headYaw) {
+        super(session, entityId, geyserId, uuid, definition, position, motion, yaw, pitch, headYaw);
+
+        setFlag(EntityFlag.CAN_FLY, true);
+        setFlag(EntityFlag.TAMED, true);
+        setFlag(EntityFlag.CAN_WALK, true);
+
+        setFlag(EntityFlag.WASD_AIR_CONTROLLED, true);
+        setFlag(EntityFlag.DOES_SERVER_AUTH_ONLY_DISMOUNT, true);
+
+        // TODO: verify which flags are necessary
+
+        setAirSupply(100);
+    }
+
+    @Override
+    @Nullable
+    protected Tag<Item> getFoodTag() {
+        return ItemTag.HAPPY_GHAST_FOOD;
+    }
+
+    @Override
+    protected float getBabySize() {
+        return 0.2375f;
+    }
+
+    public void setStaysStill(BooleanEntityMetadata entityMetadata) {
+        propertyManager.add("minecraft:can_move", !entityMetadata.getPrimitiveValue());
+        updateBedrockEntityProperties();
+    }
+
+    @NonNull
+    @Override
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
+        if (this.isBaby()) {
+            return super.testMobInteraction(hand, itemInHand);
+        } else {
+            if (!itemInHand.isEmpty()) {
+                if (session.getTagCache().is(ItemTag.HARNESSES, itemInHand)) {
+                    if (!this.body.isValid()) {
+                        // Harnesses the ghast
+                        return InteractiveTag.HARNESS_HAPPY_GHAST;
+                    }
+                }
+                // TODO: Handle shearing the harness off
+            }
+
+            if (this.body.isValid() && !session.isSneaking()) {
+                // Rides happy ghast
+                return InteractiveTag.RIDE_HORSE;
+            } else {
+                return super.testMobInteraction(hand, itemInHand);
+            }
+        }
+    }
+
+    @NonNull
+    @Override
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
+        if (this.isBaby()) {
+            return super.mobInteract(hand, itemInHand);
+        } else {
+            if (!itemInHand.isEmpty()) {
+                if (session.getTagCache().is(ItemTag.HARNESSES, itemInHand)) {
+                    if (!this.body.isValid()) {
+                        // Harnesses the ghast
+                        return InteractionResult.SUCCESS;
+                    }
+                }
+                // TODO: Handle shearing the harness off
+            }
+
+            if (this.body.isValid() && !session.isSneaking()) {
+                // Rides happy ghast
+                return InteractionResult.SUCCESS;
+            } else {
+                return super.mobInteract(hand, itemInHand);
+            }
+        }
+    }
+}

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

@@ -242,6 +242,8 @@ public class UpstreamPacketHandler extends LoggingPacketHandler {
                 stackPacket.getResourcePacks().addAll(this.resourcePackLoadEvent.orderedPacks());
                 // Allows Vibrant Visuals to be toggled in the settings
                 stackPacket.getExperiments().add(new ExperimentData("experimental_graphics", true));
+                // Enables 2025 Content Drop 2 features
+                stackPacket.getExperiments().add(new ExperimentData("y_2025_drop_2", true));
 
                 session.sendUpstreamPacket(stackPacket);
             }

core/src/main/java/org/geysermc/geyser/session/GeyserSession.java

@@ -1691,6 +1691,8 @@ public class GeyserSession implements GeyserConnection, GeyserCommandSource {
         startGamePacket.getExperiments().add(new ExperimentData("experimental_molang_features", true));
         // Allows Vibrant Visuals to appear in the settings menu
         startGamePacket.getExperiments().add(new ExperimentData("experimental_graphics", true));
+        // Enables 2025 Content Drop 2 features
+        startGamePacket.getExperiments().add(new ExperimentData("y_2025_drop_2", true));
 
         startGamePacket.setVanillaVersion("*");
         startGamePacket.setInventoriesServerAuthoritative(true);

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

@@ -73,7 +73,8 @@ public enum InteractiveTag {
     GIVE_ITEM_TO_ALLAY("allay"),
     EQUIP_WOLF_ARMOR("equipwolfarmor"),
     REMOVE_WOLF_ARMOR("removewolfarmor"),
-    REPAIR_WOLF_ARMOR("repairwolfarmor");
+    REPAIR_WOLF_ARMOR("repairwolfarmor"),
+    HARNESS_HAPPY_GHAST("equipharness");
 
     /**
      * The full string that should be passed on to the client.