Fix rowing from Java to Bedrock (#1943)

Rowing apparently broke in possibly the 1.16 update and nobody noticed until now.

connector/src/main/java/org/geysermc/connector/entity/BoatEntity.java

@@ -28,6 +28,7 @@ package org.geysermc.connector.entity;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.EntityMetadata;
 import com.nukkitx.math.vector.Vector3f;
 import com.nukkitx.protocol.bedrock.data.entity.EntityData;
+import com.nukkitx.protocol.bedrock.packet.AnimatePacket;
 import org.geysermc.connector.entity.type.EntityType;
 import org.geysermc.connector.network.session.GeyserSession;
 
@@ -105,27 +106,38 @@ public class BoatEntity extends Entity {
             metadata.put(EntityData.VARIANT, entityMetadata.getValue());
         } else if (entityMetadata.getId() == 11) {
             isPaddlingLeft = (boolean) entityMetadata.getValue();
-            if (!isPaddlingLeft) {
-                metadata.put(EntityData.ROW_TIME_LEFT, 0f);
-            }
-            else {
+            if (isPaddlingLeft) {
                 // Java sends simply "true" and "false" (is_paddling_left), Bedrock keeps sending packets as you're rowing
                 // This is an asynchronous method that emulates Bedrock rowing until "false" is sent.
                 paddleTimeLeft = 0f;
-                session.getConnector().getGeneralThreadPool().execute(() ->
-                        updateLeftPaddle(session, entityMetadata)
-                );
+                if (!this.passengers.isEmpty()) {
+                    // Get the entity by the first stored passenger and convey motion in this manner
+                    Entity entity = session.getEntityCache().getEntityByJavaId(this.passengers.iterator().nextLong());
+                    if (entity != null) {
+                        session.getConnector().getGeneralThreadPool().execute(() ->
+                                updateLeftPaddle(session, entity)
+                        );
+                    }
+                }
+            } else {
+                // Indicate that the row position should be reset
+                metadata.put(EntityData.ROW_TIME_LEFT, 0.0f);
             }
         }
         else if (entityMetadata.getId() == 12) {
             isPaddlingRight = (boolean) entityMetadata.getValue();
-            if (!isPaddlingRight) {
-                metadata.put(EntityData.ROW_TIME_RIGHT, 0f);
-            } else {
+            if (isPaddlingRight) {
                 paddleTimeRight = 0f;
-                session.getConnector().getGeneralThreadPool().execute(() ->
-                        updateRightPaddle(session, entityMetadata)
-                );
+                if (!this.passengers.isEmpty()) {
+                    Entity entity = session.getEntityCache().getEntityByJavaId(this.passengers.iterator().nextLong());
+                    if (entity != null) {
+                        session.getConnector().getGeneralThreadPool().execute(() ->
+                                updateRightPaddle(session, entity)
+                        );
+                    }
+                }
+            } else {
+                metadata.put(EntityData.ROW_TIME_RIGHT, 0.0f);
             }
         } else if (entityMetadata.getId() == 13) {
             // Possibly - I don't think this does anything?
@@ -135,27 +147,46 @@ public class BoatEntity extends Entity {
         super.updateBedrockMetadata(entityMetadata, session);
     }
 
-    public void updateLeftPaddle(GeyserSession session, EntityMetadata entityMetadata) {
+    @Override
+    public void updateBedrockMetadata(GeyserSession session) {
+        super.updateBedrockMetadata(session);
+
+        // As these indicate to reset rowing, remove them until it is time to send them out again.
+        metadata.remove(EntityData.ROW_TIME_LEFT);
+        metadata.remove(EntityData.ROW_TIME_RIGHT);
+    }
+
+    private void updateLeftPaddle(GeyserSession session, Entity rower) {
         if (isPaddlingLeft) {
             paddleTimeLeft += ROWING_SPEED;
-            metadata.put(EntityData.ROW_TIME_LEFT, paddleTimeLeft);
-            super.updateBedrockMetadata(entityMetadata, session);
+            sendAnimationPacket(session, rower, AnimatePacket.Action.ROW_LEFT, paddleTimeLeft);
+
             session.getConnector().getGeneralThreadPool().schedule(() ->
-                    updateLeftPaddle(session, entityMetadata),
+                    updateLeftPaddle(session, rower),
                     100,
                     TimeUnit.MILLISECONDS
             );
-        }}
+        }
+    }
 
-    public void updateRightPaddle(GeyserSession session, EntityMetadata entityMetadata) {
+    private void updateRightPaddle(GeyserSession session, Entity rower) {
         if (isPaddlingRight) {
             paddleTimeRight += ROWING_SPEED;
-            metadata.put(EntityData.ROW_TIME_RIGHT, paddleTimeRight);
-            super.updateBedrockMetadata(entityMetadata, session);
+            sendAnimationPacket(session, rower, AnimatePacket.Action.ROW_RIGHT, paddleTimeRight);
+
             session.getConnector().getGeneralThreadPool().schedule(() ->
-                            updateRightPaddle(session, entityMetadata),
+                            updateRightPaddle(session, rower),
                     100,
                     TimeUnit.MILLISECONDS
             );
-        }}
+        }
+    }
+
+    private void sendAnimationPacket(GeyserSession session, Entity rower, AnimatePacket.Action action, float rowTime) {
+        AnimatePacket packet = new AnimatePacket();
+        packet.setRuntimeEntityId(rower.getGeyserId());
+        packet.setAction(action);
+        packet.setRowingTime(rowTime);
+        session.sendUpstreamPacket(packet);
+    }
 }