Implement AnimateEntityPacket

src/main/java/cn/nukkit/entity/Entity.java

@@ -2525,4 +2525,11 @@ public int hashCode() {
         hash = (int) (29 * hash + this.getId());
         return hash;
     }
+
+    public void playAnimation(String animation) {
+        AnimateEntityPacket animateEntityPacket = new AnimateEntityPacket();
+        animateEntityPacket.animation = animation;
+        animateEntityPacket.runtimeEntityIds.add(this.id);
+        Server.broadcastPacket(this.hasSpawned.values(), animateEntityPacket);
+    }
 }

src/main/java/cn/nukkit/network/protocol/AnimateEntityPacket.java

@@ -0,0 +1,77 @@
+package cn.nukkit.network.protocol;
+
+import it.unimi.dsi.fastutil.longs.LongArrayList;
+import it.unimi.dsi.fastutil.longs.LongList;
+import lombok.ToString;
+
+/**
+ * Used to trigger an entity animation on the specified runtime IDs to the client that receives it.
+ * Source: <a href="https://github.com/CloudburstMC/Protocol">...</a>
+ * Default values from <a href="https://wiki.vg/Bedrock_Protocol">...</a>
+ */
+@ToString
+public class AnimateEntityPacket extends DataPacket {
+
+    public static final byte NETWORK_ID = ProtocolInfo.ANIMATE_ENTITY_PACKET;
+
+    /**
+     * Name of the to play on the entities specified in {@link #runtimeEntityIds}
+     */
+    public String animation;
+
+    /**
+     * The entity state to move to when the animation has finished playing.
+     */
+    public String nextState = "default";
+
+    /**
+     * Expression to check if the animation needs to stop.
+     */
+    public String stopExpression = "query.any_animation_finished";
+
+    /**
+     * The molang stop expression version
+     */
+    public int stopExpressionVersion;
+
+    /**
+     * Name of the animation controller to use.
+     */
+    public String controller = "__runtime_controller";
+
+    /**
+     * Time taken to blend out of the specified animation.
+     */
+    public float blendOutTime = 0f;
+
+    /**
+     * Entity runtime IDs to run the animation on when sent to the client.
+     */
+    public final LongList runtimeEntityIds = new LongArrayList();
+
+    @Override
+    public void decode() {
+    }
+
+    @Override
+    public void encode() {
+        this.reset();
+
+        this.putString(this.animation);
+        this.putString(this.nextState);
+        this.putString(this.stopExpression);
+        this.putLInt(this.stopExpressionVersion);
+        this.putString(this.controller);
+        this.putLFloat(this.blendOutTime);
+
+        this.putUnsignedVarInt(this.runtimeEntityIds.size());
+        for (long runtimeId : this.runtimeEntityIds) {
+            this.putUnsignedVarLong(runtimeId);
+        }
+    }
+
+    @Override
+    public byte pid() {
+        return NETWORK_ID;
+    }
+}