Fix EffectCure syncing by introducing connection aware StreamCodec

patches/net/minecraft/client/multiplayer/ClientConfigurationPacketListenerImpl.java.patch

@@ -22,7 +22,16 @@
      }
 
      @Override
-@@ -135,10 +_,17 @@
+@@ -121,7 +_,7 @@
+         );
+         this.connection
+             .setupInboundProtocol(
+-                GameProtocols.CLIENTBOUND.bind(RegistryFriendlyByteBuf.decorator(registryaccess$frozen)),
++                GameProtocols.CLIENTBOUND.bind(RegistryFriendlyByteBuf.decorator(registryaccess$frozen, this.connectionType)),
+                 new ClientPacketListener(
+                     this.minecraft,
+                     this.connection,
+@@ -135,12 +_,19 @@
                          this.postDisconnectScreen,
                          this.serverCookies,
                          this.chatState,
@@ -39,8 +48,11 @@
 +        }
 +        net.neoforged.neoforge.network.registration.NetworkRegistry.onConfigurationFinished(this);
          this.connection.send(ServerboundFinishConfigurationPacket.INSTANCE);
-         this.connection.setupOutboundProtocol(GameProtocols.SERVERBOUND.bind(RegistryFriendlyByteBuf.decorator(registryaccess$frozen)));
+-        this.connection.setupOutboundProtocol(GameProtocols.SERVERBOUND.bind(RegistryFriendlyByteBuf.decorator(registryaccess$frozen)));
++        this.connection.setupOutboundProtocol(GameProtocols.SERVERBOUND.bind(RegistryFriendlyByteBuf.decorator(registryaccess$frozen, this.connectionType)));
      }
+
+     @Override
 @@ -152,5 +_,51 @@
      public void onDisconnect(Component p_314649_) {
          super.onDisconnect(p_314649_);

patches/net/minecraft/network/RegistryFriendlyByteBuf.java.patch

@@ -0,0 +1,35 @@
+--- a/net/minecraft/network/RegistryFriendlyByteBuf.java
++++ b/net/minecraft/network/RegistryFriendlyByteBuf.java
+@@ -6,10 +_,22 @@
+
+ public class RegistryFriendlyByteBuf extends FriendlyByteBuf {
+     private final RegistryAccess registryAccess;
++    private final net.neoforged.neoforge.network.connection.ConnectionType connectionType;
+
+     public RegistryFriendlyByteBuf(ByteBuf p_320951_, RegistryAccess p_319803_) {
+         super(p_320951_);
+         this.registryAccess = p_319803_;
++        this.connectionType = net.neoforged.neoforge.network.connection.ConnectionType.NEOFORGE;
++    }
++
++    public RegistryFriendlyByteBuf(ByteBuf p_320951_, RegistryAccess p_319803_, net.neoforged.neoforge.network.connection.ConnectionType connectionType) {
++        super(p_320951_);
++        this.registryAccess = p_319803_;
++        this.connectionType = connectionType;
++    }
++
++    public net.neoforged.neoforge.network.connection.ConnectionType getConnectionType() {
++        return this.connectionType;
+     }
+
+     public RegistryAccess registryAccess() {
+@@ -18,5 +_,9 @@
+
+     public static Function<ByteBuf, RegistryFriendlyByteBuf> decorator(RegistryAccess p_320166_) {
+         return p_320793_ -> new RegistryFriendlyByteBuf(p_320793_, p_320166_);
++    }
++
++    public static Function<ByteBuf, RegistryFriendlyByteBuf> decorator(RegistryAccess p_320166_, net.neoforged.neoforge.network.connection.ConnectionType connectionType) {
++        return p_320793_ -> new RegistryFriendlyByteBuf(p_320793_, p_320166_, connectionType);
+     }
+ }

patches/net/minecraft/server/network/ServerConfigurationPacketListenerImpl.java.patch

@@ -56,10 +56,12 @@
      }
 
      @Override
-@@ -118,6 +_,12 @@
+@@ -117,7 +_,13 @@
+     public void handleConfigurationFinished(ServerboundFinishConfigurationPacket p_294283_) {
          PacketUtils.ensureRunningOnSameThread(p_294283_, this, this.server);
          this.finishCurrentTask(JoinWorldTask.TYPE);
-         this.connection.setupOutboundProtocol(GameProtocols.CLIENTBOUND.bind(RegistryFriendlyByteBuf.decorator(this.server.registryAccess())));
+-        this.connection.setupOutboundProtocol(GameProtocols.CLIENTBOUND.bind(RegistryFriendlyByteBuf.decorator(this.server.registryAccess())));
++        this.connection.setupOutboundProtocol(GameProtocols.CLIENTBOUND.bind(RegistryFriendlyByteBuf.decorator(this.server.registryAccess(), this.connectionType)));
 +        // Packets can only be sent after the outbound protocol is set up again
 +        if (this.connectionType == net.neoforged.neoforge.network.connection.ConnectionType.OTHER) {
 +            //We need to also initialize this here, as the client may have sent the packet before we have finished our configuration.

patches/net/minecraft/server/players/PlayerList.java.patch

@@ -8,6 +8,15 @@
 
      public PlayerList(MinecraftServer p_203842_, LayeredRegistryAccess<RegistryLayer> p_251844_, PlayerDataStorage p_203844_, int p_203845_) {
          this.server = p_203842_;
+@@ -177,7 +_,7 @@
+         p_11263_.loadGameTypes(optional1.orElse(null));
+         ServerGamePacketListenerImpl servergamepacketlistenerimpl = new ServerGamePacketListenerImpl(this.server, p_11262_, p_11263_, p_301988_);
+         p_11262_.setupInboundProtocol(
+-            GameProtocols.SERVERBOUND.bind(RegistryFriendlyByteBuf.decorator(this.server.registryAccess())), servergamepacketlistenerimpl
++            GameProtocols.SERVERBOUND.bind(RegistryFriendlyByteBuf.decorator(this.server.registryAccess(), servergamepacketlistenerimpl.getConnectionType())), servergamepacketlistenerimpl
+         );
+         GameRules gamerules = serverlevel1.getGameRules();
+         boolean flag = gamerules.getBoolean(GameRules.RULE_DO_IMMEDIATE_RESPAWN);
 @@ -201,6 +_,7 @@
          servergamepacketlistenerimpl.send(new ClientboundChangeDifficultyPacket(leveldata.getDifficulty(), leveldata.isDifficultyLocked()));
          servergamepacketlistenerimpl.send(new ClientboundPlayerAbilitiesPacket(p_11263_.getAbilities()));

patches/net/minecraft/world/effect/MobEffectInstance.java.patch

@@ -76,26 +76,30 @@
          public static final MapCodec<MobEffectInstance.Details> MAP_CODEC = MapCodec.recursive(
              "MobEffectInstance.Details",
              p_323465_ -> RecordCodecBuilder.mapCodec(
-@@ -409,10 +_,13 @@
+@@ -408,13 +_,14 @@
+                                 Codec.BOOL.optionalFieldOf("ambient", Boolean.valueOf(false)).forGetter(MobEffectInstance.Details::ambient),
                                  Codec.BOOL.optionalFieldOf("show_particles", Boolean.valueOf(true)).forGetter(MobEffectInstance.Details::showParticles),
                                  Codec.BOOL.optionalFieldOf("show_icon").forGetter(p_323788_ -> Optional.of(p_323788_.showIcon())),
-                                 p_323465_.optionalFieldOf("hidden_effect").forGetter(MobEffectInstance.Details::hiddenEffect)
-+                                // Neo: Add additional serialization logic for custom EffectCure(s)
-+                                , net.neoforged.neoforge.common.util.NeoForgeExtraCodecs.setOf(net.neoforged.neoforge.common.EffectCure.CODEC).optionalFieldOf("neoforge:cures").forGetter(MobEffectInstance.Details::cures)
+-                                p_323465_.optionalFieldOf("hidden_effect").forGetter(MobEffectInstance.Details::hiddenEffect)
++                                p_323465_.optionalFieldOf("hidden_effect").forGetter(MobEffectInstance.Details::hiddenEffect),
++                                net.neoforged.neoforge.common.util.NeoForgeExtraCodecs.setOf(net.neoforged.neoforge.common.EffectCure.CODEC).optionalFieldOf("neoforge:cures").forGetter(MobEffectInstance.Details::cures)
                              )
                              .apply(p_324063_, MobEffectInstance.Details::create)
                  )
          );
-+        // TODO: https://github.com/neoforged/NeoForge/issues/986 - Fix this to have vanilla-compatible sync.
-         public static final StreamCodec<ByteBuf, MobEffectInstance.Details> STREAM_CODEC = StreamCodec.recursive(
-             p_329990_ -> StreamCodec.composite(
+-        public static final StreamCodec<ByteBuf, MobEffectInstance.Details> STREAM_CODEC = StreamCodec.recursive(
+-            p_329990_ -> StreamCodec.composite(
++        public static final StreamCodec<RegistryFriendlyByteBuf, MobEffectInstance.Details> STREAM_CODEC = StreamCodec.recursive(
++            p_329990_ -> net.neoforged.neoforge.network.codec.NeoForgeStreamCodecs.composite(
                      ByteBufCodecs.VAR_INT,
-@@ -427,14 +_,23 @@
+                     MobEffectInstance.Details::amplifier,
+                     ByteBufCodecs.VAR_INT,
+@@ -427,14 +_,16 @@
                      MobEffectInstance.Details::showIcon,
                      p_329990_.apply(ByteBufCodecs::optional),
                      MobEffectInstance.Details::hiddenEffect,
-+                    // net.neoforged.neoforge.common.EffectCure.STREAM_CODEC.<java.util.Set<net.neoforged.neoforge.common.EffectCure>>apply(ByteBufCodecs.collection(java.util.HashSet::new)).apply(ByteBufCodecs::optional),
-+                    // MobEffectInstance.Details::cures,
++                    net.neoforged.neoforge.common.EffectCure.STREAM_CODEC.<RegistryFriendlyByteBuf>cast().<java.util.Set<net.neoforged.neoforge.common.EffectCure>>apply(ByteBufCodecs.collection(java.util.HashSet::new)).apply(codec -> net.neoforged.neoforge.network.codec.NeoForgeStreamCodecs.connectionAware(ByteBufCodecs.optional(codec), StreamCodec.unit(Optional.empty()))),
++                    MobEffectInstance.Details::cures,
                      MobEffectInstance.Details::new
                  )
          );
@@ -105,15 +109,7 @@
 +            int p_323657_, int p_324205_, boolean p_324263_, boolean p_324000_, Optional<Boolean> p_323607_, Optional<MobEffectInstance.Details> p_324604_, Optional<java.util.Set<net.neoforged.neoforge.common.EffectCure>> cures
          ) {
 -            return new MobEffectInstance.Details(p_323657_, p_324205_, p_324263_, p_324000_, p_323607_.orElse(p_324000_), p_324604_);
--        }
 +            return new MobEffectInstance.Details(p_323657_, p_324205_, p_324263_, p_324000_, p_323607_.orElse(p_324000_), p_324604_, cures);
-+        }
-+
-+        // TODO: https://github.com/neoforged/NeoForge/issues/986 - Delete these once custom cure sync is fixed.
-+        @Deprecated(forRemoval = true, since = "1.20.6")
-+        private Details(int amplifier, int duration, boolean ambient, boolean showParticles, boolean showIcon, Optional<MobEffectInstance.Details> hiddenEffect) {
-+            this(amplifier, duration, ambient, showParticles, showIcon, hiddenEffect, Optional.empty());
-+        }
-+
+         }
      }
  }

src/main/java/net/neoforged/neoforge/network/codec/NeoForgeStreamCodecs.java

@@ -10,6 +10,7 @@
 import java.util.function.Supplier;
 import net.minecraft.core.Registry;
 import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.network.RegistryFriendlyByteBuf;
 import net.minecraft.network.codec.StreamCodec;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.world.level.ChunkPos;
@@ -91,6 +92,29 @@ public void encode(B buf, ResourceKey<? extends Registry<?>> value) {
         };
     }
 
+    /**
+     * Creates a stream codec that uses different implementation depending on the {@link net.neoforged.neoforge.network.connection.ConnectionType}.
+     * Should be used to keep vanilla connection compatibility.
+     */
+    public static <V> StreamCodec<RegistryFriendlyByteBuf, V> connectionAware(
+            StreamCodec<? super RegistryFriendlyByteBuf, V> neoForgeCodec,
+            StreamCodec<? super RegistryFriendlyByteBuf, V> otherCodec) {
+        return new StreamCodec<>() {
+            @Override
+            public V decode(RegistryFriendlyByteBuf buf) {
+                return buf.getConnectionType().isNeoForge() ? neoForgeCodec.decode(buf) : otherCodec.decode(buf);
+            }
+
+            @Override
+            public void encode(RegistryFriendlyByteBuf buf, V value) {
+                switch (buf.getConnectionType()) {
+                    case NEOFORGE -> neoForgeCodec.encode(buf, value);
+                    case OTHER -> otherCodec.encode(buf, value);
+                }
+            }
+        };
+    }
+
     public static <B, C, T1, T2, T3, T4, T5, T6, T7> StreamCodec<B, C> composite(
             final StreamCodec<? super B, T1> codec1,
             final Function<C, T1> getter1,