From 9d78b326c6ea28d1e363ce7fab58275e095a03e5 Mon Sep 17 00:00:00 2001
From: Jason Penilla <11360596+jpenilla@users.noreply.github.com>
Date: Wed, 29 May 2024 21:37:33 -0700
Subject: [PATCH] Fix tab list header/footer on Paper 1.20.6

---
 .../adventure/platform/bukkit/PaperFacet.java | 30 +++++++++++++++----
 1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/platform-bukkit/src/main/java/net/kyori/adventure/platform/bukkit/PaperFacet.java b/platform-bukkit/src/main/java/net/kyori/adventure/platform/bukkit/PaperFacet.java
index 170ba17e..d2f9dd2c 100644
--- a/platform-bukkit/src/main/java/net/kyori/adventure/platform/bukkit/PaperFacet.java
+++ b/platform-bukkit/src/main/java/net/kyori/adventure/platform/bukkit/PaperFacet.java
@@ -46,11 +46,22 @@
 class PaperFacet<V extends CommandSender> extends FacetBase<V> {
   private static final boolean SUPPORTED = isEnabled("paper", true);
   static final Class<?> NATIVE_COMPONENT_CLASS = findClass(String.join(".", "net", "kyori", "adventure", "text", "Component"));
+  private static final MethodHandle PAPER_ADVENTURE_AS_VANILLA = findAsVanillaMethod();
   private static final Class<?> NATIVE_GSON_COMPONENT_SERIALIZER_CLASS = findClass(String.join(".", "net", "kyori", "adventure", "text", "serializer", "gson", "GsonComponentSerializer"));
   private static final Class<?> NATIVE_GSON_COMPONENT_SERIALIZER_IMPL_CLASS = findClass(String.join(".", "net", "kyori", "adventure", "text", "serializer", "gson", "GsonComponentSerializerImpl"));
   private static final MethodHandle NATIVE_GSON_COMPONENT_SERIALIZER_GSON_GETTER = findStaticMethod(NATIVE_GSON_COMPONENT_SERIALIZER_CLASS, "gson", NATIVE_GSON_COMPONENT_SERIALIZER_CLASS);
   private static final MethodHandle NATIVE_GSON_COMPONENT_SERIALIZER_DESERIALIZE_METHOD = findNativeDeserializeMethod();
 
+  private static @Nullable MethodHandle findAsVanillaMethod() {
+    try {
+      final Class<?> paperAdventure = findClass("io.papermc.paper.adventure.PaperAdventure");
+      final Method method = paperAdventure.getDeclaredMethod("asVanilla", NATIVE_COMPONENT_CLASS);
+      return lookup().unreflect(method);
+    } catch (final NoSuchMethodException | IllegalAccessException | NullPointerException e) {
+      return null;
+    }
+  }
+
   private static @Nullable MethodHandle findNativeDeserializeMethod() {
     try {
       final Method method = NATIVE_GSON_COMPONENT_SERIALIZER_IMPL_CLASS.getDeclaredMethod("deserialize", String.class);
@@ -145,15 +156,24 @@ static class TabList extends CraftBukkitFacet.TabList {
 
     @Override
     public boolean isSupported() {
-      return SUPPORTED && super.isSupported() && CLIENTBOUND_TAB_LIST_PACKET_SET_HEADER != null && CLIENTBOUND_TAB_LIST_PACKET_SET_FOOTER != null;
+      return SUPPORTED && super.isSupported()
+              && ((CLIENTBOUND_TAB_LIST_PACKET_SET_HEADER != null && CLIENTBOUND_TAB_LIST_PACKET_SET_FOOTER != null)
+              || PAPER_ADVENTURE_AS_VANILLA != null);
     }
 
     @Override
     protected Object create117Packet(final Player viewer, final @Nullable Object header, final @Nullable Object footer) throws Throwable {
-      final Object packet = CLIENTBOUND_TAB_LIST_PACKET_CTOR.invoke(null, null);
-      CLIENTBOUND_TAB_LIST_PACKET_SET_HEADER.invoke(packet, header == null ? this.createMessage(viewer, Component.empty()) : header);
-      CLIENTBOUND_TAB_LIST_PACKET_SET_FOOTER.invoke(packet, footer == null ? this.createMessage(viewer, Component.empty()) : footer);
-      return packet;
+      if (CLIENTBOUND_TAB_LIST_PACKET_SET_FOOTER == null && CLIENTBOUND_TAB_LIST_PACKET_SET_HEADER == null) {
+        return CLIENTBOUND_TAB_LIST_PACKET_CTOR.invoke(
+          PAPER_ADVENTURE_AS_VANILLA.invoke(header == null ? this.createMessage(viewer, Component.empty()) : header),
+          PAPER_ADVENTURE_AS_VANILLA.invoke(footer == null ? this.createMessage(viewer, Component.empty()) : footer)
+        );
+      } else {
+        final Object packet = CLIENTBOUND_TAB_LIST_PACKET_CTOR.invoke(null, null);
+        CLIENTBOUND_TAB_LIST_PACKET_SET_HEADER.invoke(packet, header == null ? this.createMessage(viewer, Component.empty()) : header);
+        CLIENTBOUND_TAB_LIST_PACKET_SET_FOOTER.invoke(packet, footer == null ? this.createMessage(viewer, Component.empty()) : footer);
+        return packet;
+      }
     }
 
     @Override