From 304f9b34fd597347d51c96b0fdd00e88d0488946 Mon Sep 17 00:00:00 2001
From: Matsv <mats@matsv.nl>
Date: Tue, 15 Nov 2016 18:10:14 +0100
Subject: [PATCH] Send empty metadata flags on server switch to prevent an
 Elytra glitch on 1.8 fixes #555

---
 .../bungee/handlers/BungeeServerHandler.java  |  3 +-
 .../bungee/listeners/ElytraPatch.java         | 45 +++++++++++++++++++
 .../bungee/platform/BungeeViaLoader.java      |  2 +
 3 files changed, 49 insertions(+), 1 deletion(-)
 create mode 100644 bungee/src/main/java/us/myles/ViaVersion/bungee/listeners/ElytraPatch.java

diff --git a/bungee/src/main/java/us/myles/ViaVersion/bungee/handlers/BungeeServerHandler.java b/bungee/src/main/java/us/myles/ViaVersion/bungee/handlers/BungeeServerHandler.java
index 88d5ba08e..7e77b9b6e 100644
--- a/bungee/src/main/java/us/myles/ViaVersion/bungee/handlers/BungeeServerHandler.java
+++ b/bungee/src/main/java/us/myles/ViaVersion/bungee/handlers/BungeeServerHandler.java
@@ -5,6 +5,7 @@ import net.md_5.bungee.api.event.ServerConnectEvent;
 import net.md_5.bungee.api.event.ServerConnectedEvent;
 import net.md_5.bungee.api.plugin.Listener;
 import net.md_5.bungee.event.EventHandler;
+import net.md_5.bungee.event.EventPriority;
 import us.myles.ViaVersion.api.Pair;
 import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.data.UserConnection;
@@ -67,7 +68,7 @@ public class BungeeServerHandler implements Listener {
         }
     }
 
-    @EventHandler
+    @EventHandler(priority = EventPriority.LOWEST)
     public void onServerConnected(ServerConnectedEvent e) {
         try {
             checkServerChange(e, Via.getManager().getConnection(e.getPlayer().getUniqueId()));
diff --git a/bungee/src/main/java/us/myles/ViaVersion/bungee/listeners/ElytraPatch.java b/bungee/src/main/java/us/myles/ViaVersion/bungee/listeners/ElytraPatch.java
new file mode 100644
index 000000000..68e5583ce
--- /dev/null
+++ b/bungee/src/main/java/us/myles/ViaVersion/bungee/listeners/ElytraPatch.java
@@ -0,0 +1,45 @@
+package us.myles.ViaVersion.bungee.listeners;
+
+import net.md_5.bungee.api.event.ServerConnectedEvent;
+import net.md_5.bungee.api.plugin.Listener;
+import net.md_5.bungee.event.EventHandler;
+import net.md_5.bungee.event.EventPriority;
+import us.myles.ViaVersion.api.PacketWrapper;
+import us.myles.ViaVersion.api.Via;
+import us.myles.ViaVersion.api.data.UserConnection;
+import us.myles.ViaVersion.api.minecraft.metadata.Metadata;
+import us.myles.ViaVersion.api.minecraft.metadata.types.MetaType1_9;
+import us.myles.ViaVersion.api.type.Type;
+import us.myles.ViaVersion.api.type.types.version.Types1_9;
+import us.myles.ViaVersion.protocols.base.ProtocolInfo;
+import us.myles.ViaVersion.protocols.protocol1_9to1_8.Protocol1_9TO1_8;
+import us.myles.ViaVersion.protocols.protocol1_9to1_8.storage.EntityTracker;
+
+import java.util.Collections;
+
+/*
+ * This patches https://github.com/MylesIsCool/ViaVersion/issues/555
+ */
+public class ElytraPatch implements Listener {
+
+    @EventHandler(priority = EventPriority.HIGH)
+    public void onServerConnected(ServerConnectedEvent event) {
+        UserConnection user = Via.getManager().getConnection(event.getPlayer().getUniqueId());
+        if (user == null) return;
+
+        try {
+            if (user.get(ProtocolInfo.class).getPipeline().contains(Protocol1_9TO1_8.class)) {
+                int entityId = user.get(EntityTracker.class).getProvidedEntityId();
+
+                PacketWrapper wrapper = new PacketWrapper(0x39, null, user);
+
+                wrapper.write(Type.VAR_INT, entityId);
+                wrapper.write(Types1_9.METADATA_LIST, Collections.singletonList(new Metadata(0, MetaType1_9.Byte, (byte) 0)));
+
+                wrapper.send(Protocol1_9TO1_8.class);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
diff --git a/bungee/src/main/java/us/myles/ViaVersion/bungee/platform/BungeeViaLoader.java b/bungee/src/main/java/us/myles/ViaVersion/bungee/platform/BungeeViaLoader.java
index e89cd22bf..e721f3eb2 100644
--- a/bungee/src/main/java/us/myles/ViaVersion/bungee/platform/BungeeViaLoader.java
+++ b/bungee/src/main/java/us/myles/ViaVersion/bungee/platform/BungeeViaLoader.java
@@ -6,6 +6,7 @@ import us.myles.ViaVersion.BungeePlugin;
 import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.platform.ViaPlatformLoader;
 import us.myles.ViaVersion.bungee.handlers.BungeeServerHandler;
+import us.myles.ViaVersion.bungee.listeners.ElytraPatch;
 import us.myles.ViaVersion.bungee.listeners.MainHandPatch;
 import us.myles.ViaVersion.bungee.listeners.UpdateListener;
 import us.myles.ViaVersion.bungee.providers.BungeeEntityIdProvider;
@@ -29,6 +30,7 @@ public class BungeeViaLoader implements ViaPlatformLoader {
         ProxyServer.getInstance().getPluginManager().registerListener(plugin, new UpdateListener());
         ProxyServer.getInstance().getPluginManager().registerListener(plugin, new BungeeServerHandler());
         ProxyServer.getInstance().getPluginManager().registerListener(plugin, new MainHandPatch());
+        ProxyServer.getInstance().getPluginManager().registerListener(plugin, new ElytraPatch());
 
         // Providers
         Via.getManager().getProviders().use(MovementTransmitterProvider.class, new BungeeMovementTransmitter());