fix: invalid packets in PacketEvents on 1.13+ servers with 1.12.2- cl…

…ients and 1.12.2- servers with 1.13+ clients

build.gradle.kts

@@ -1,5 +1,5 @@
 allprojects {
-  version = "2.1.12"
+  version = "2.1.13-SNAPSHOT"
   group = "net.megavex"
   description = "Powerful packet-level scoreboard library for Paper/Spigot servers"
 }

versions/packetevents/src/main/java/net/megavex/scoreboardlibrary/implementation/packetAdapter/packetevents/PacketAdapterProviderImpl.java

@@ -2,51 +2,52 @@
 
 import com.github.retrooper.packetevents.PacketEvents;
 import com.github.retrooper.packetevents.PacketEventsAPI;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
 import com.github.retrooper.packetevents.protocol.player.ClientVersion;
-import com.github.retrooper.packetevents.wrapper.PacketWrapper;
 import net.megavex.scoreboardlibrary.implementation.commons.LineRenderingStrategy;
-import net.megavex.scoreboardlibrary.implementation.packetAdapter.objective.ObjectivePacketAdapter;
 import net.megavex.scoreboardlibrary.implementation.packetAdapter.PacketAdapterProvider;
-import net.megavex.scoreboardlibrary.implementation.packetAdapter.PacketSender;
-import net.megavex.scoreboardlibrary.implementation.packetAdapter.team.TeamsPacketAdapter;
+import net.megavex.scoreboardlibrary.implementation.packetAdapter.objective.ObjectivePacketAdapter;
 import net.megavex.scoreboardlibrary.implementation.packetAdapter.packetevents.team.TeamsPacketAdapterImpl;
+import net.megavex.scoreboardlibrary.implementation.packetAdapter.team.TeamsPacketAdapter;
+import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 
 @SuppressWarnings("unused")
-public class PacketAdapterProviderImpl implements PacketAdapterProvider, PacketSender<PacketWrapper<?>> {
+public class PacketAdapterProviderImpl implements PacketAdapterProvider {
   private final PacketEventsAPI<?> packetEvents;
+  private final PacketEventsSender packetSender;
 
   public PacketAdapterProviderImpl() {
     this.packetEvents = PacketEvents.getAPI();
     if (this.packetEvents == null) {
       throw new IllegalStateException("PacketEvents exists in classpath but isn't loaded");
     }
+    this.packetSender = new PacketEventsSender(this.packetEvents);
   }
 
   @Override
   public @NotNull TeamsPacketAdapter createTeamPacketAdapter(@NotNull String teamName) {
-    return new TeamsPacketAdapterImpl(this, teamName);
+    return new TeamsPacketAdapterImpl(packetSender, teamName);
   }
 
   @Override
   public @NotNull ObjectivePacketAdapter createObjectiveAdapter(@NotNull String objectiveName) {
-    return new ObjectivePacketAdapterImpl(this, packetEvents, objectiveName);
+    return new ObjectivePacketAdapterImpl(packetSender, packetEvents, objectiveName);
   }
 
   @Override
   public @NotNull LineRenderingStrategy lineRenderingStrategy(@NotNull Player player) {
-    ClientVersion ver = packetEvents.getPlayerManager().getClientVersion(player);
-    return ver.isNewerThanOrEquals(ClientVersion.V_1_13) ? LineRenderingStrategy.MODERN : LineRenderingStrategy.LEGACY;
-  }
-
-  public void sendPacket(@NotNull Player player, @NotNull PacketWrapper<?> packet) {
-    packetEvents.getPlayerManager().sendPacket(player, packet);
-  }
+    ServerVersion serverVer = packetEvents.getServerManager().getVersion();
+    if (serverVer.isOlderThan(ServerVersion.V_1_13)) {
+      return LineRenderingStrategy.LEGACY;
+    }
 
-  public void sendPacket(@NotNull Iterable<Player> players, @NotNull PacketWrapper<?> packet) {
-    for (Player player : players) {
-      sendPacket(player, packet);
+    if (Bukkit.getServer().getPluginManager().isPluginEnabled("ProtocolSupport")) {
+      return LineRenderingStrategy.MODERN;
     }
+
+    ClientVersion clientVer = packetEvents.getPlayerManager().getClientVersion(player);
+    return clientVer.isNewerThanOrEquals(ClientVersion.V_1_13) ? LineRenderingStrategy.MODERN : LineRenderingStrategy.LEGACY;
   }
 }

versions/packetevents/src/main/java/net/megavex/scoreboardlibrary/implementation/packetAdapter/packetevents/PacketEventsSender.java

@@ -0,0 +1,61 @@
+package net.megavex.scoreboardlibrary.implementation.packetAdapter.packetevents;
+
+import com.github.retrooper.packetevents.PacketEventsAPI;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
+import com.github.retrooper.packetevents.netty.buffer.ByteBufHelper;
+import com.github.retrooper.packetevents.netty.channel.ChannelHelper;
+import com.github.retrooper.packetevents.protocol.player.ClientVersion;
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.wrapper.PacketWrapper;
+import net.megavex.scoreboardlibrary.implementation.packetAdapter.PacketSender;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Objects;
+
+public class PacketEventsSender implements PacketSender<PacketWrapper<?>> {
+  private final PacketEventsAPI<?> packetEvents;
+
+  public PacketEventsSender(@NotNull PacketEventsAPI<?> packetEvents) {
+    this.packetEvents = packetEvents;
+  }
+
+  @SuppressWarnings("UnstableApiUsage, deprecation")
+  @Override
+  public void sendPacket(Player player, PacketWrapper<?> packet) {
+    ServerVersion serverVer = packetEvents.getServerManager().getVersion();
+    ClientVersion clientVer = packetEvents.getPlayerManager().getClientVersion(player);
+    if (serverVer.isOlderThan(ServerVersion.V_1_13) || clientVer.isNewerThanOrEquals(ClientVersion.V_1_13)) {
+      packetEvents.getPlayerManager().sendPacket(player, packet);
+      return;
+    }
+
+    // This is a hack to send packets directly skipping plugins such as ViaVersion and ViaRewind
+    // Based on https://discord.com/channels/721686193061888071/755472595096174873/1193239879560212520
+    // (PacketEvents Discord)
+
+    User user = packetEvents.getPlayerManager().getUser(player);
+    if (user == null) {
+      return;
+    }
+
+    Object channel = user.getChannel();
+    if (!ChannelHelper.isOpen(channel)) {
+      return;
+    }
+
+    String viaEncoder = "via-encoder";
+    if (ChannelHelper.getPipelineHandler(channel, viaEncoder) == null) {
+      packetEvents.getPlayerManager().sendPacket(player, packet);
+      return;
+    }
+
+    packet.buffer = ChannelHelper.pooledByteBuf(channel);
+
+    int id = Objects.requireNonNull(packet.getPacketTypeData().getPacketType()).getId(user.getClientVersion());
+    ByteBufHelper.writeVarInt(packet.buffer, id);
+    packet.setServerVersion(clientVer.toServerVersion());
+    packet.write();
+    ChannelHelper.writeAndFlushInContext(channel, viaEncoder, packet.buffer);
+  }
+}