Fixes #6

samolego · Jun 15, 2021 · 3b3cf20 · 3b3cf20
1 parent a50d53f
commit 3b3cf20
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Showing 3 changed files with 56 additions and 9 deletions.
diff --git a/build.gradle b/build.gradle
@@ -21,6 +21,10 @@ repositories {
 	maven {
 		url 'https://jitpack.io'
 	}
+	maven {
+		name = "TomTheGeek-repo"
+		url = "https://maven.tomthegeek.ml/releases/"
+	}
 }
 
 def ENV = System.getenv()
@@ -37,6 +41,8 @@ dependencies {
 	// LuckPerms
 	modImplementation 'me.lucko:fabric-permissions-api:0.1-SNAPSHOT'
 
+	// WDMNF
+	modRuntime("com.github.tom_the_geek:wdmnf:1.0.0+mc.1.17")
 	//modRuntime "com.github.CaffeineMC:hydrogen-fabric:mc1.16.5-v0.2.0"
 	//modRuntime "com.github.astei:lazydfu:0.1.2"
 }

diff --git a/src/main/java/org/samo_lego/healthcare/mixin/EntityTrackerUpdateS2CPacketAccessor.java b/src/main/java/org/samo_lego/healthcare/mixin/EntityTrackerUpdateS2CPacketAccessor.java
@@ -10,13 +10,18 @@
 
 @Mixin(EntityTrackerUpdateS2CPacket.class)
 public interface EntityTrackerUpdateS2CPacketAccessor {
-    @Accessor("id")
-    int getId();
 
     @Accessor("trackedValues")
     List<DataTracker.Entry<?>> getTrackedValues();
 
     @Mutable
     @Accessor("trackedValues")
     void setTrackedValues(List<DataTracker.Entry<?>> trackedValues);
+
+    @Accessor("id")
+    int getId();
+
+    @Mutable
+    @Accessor("id")
+    void setId(int id);
 }
diff --git a/src/main/java/org/samo_lego/healthcare/mixin/ServerPlayNetworkHandlerMixin_HealthTag.java b/src/main/java/org/samo_lego/healthcare/mixin/ServerPlayNetworkHandlerMixin_HealthTag.java
@@ -6,6 +6,7 @@
 import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.data.DataTracker;
 import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.network.ClientConnection;
 import net.minecraft.network.Packet;
 import net.minecraft.network.packet.s2c.play.EntityTrackerUpdateS2CPacket;
 import net.minecraft.server.network.ServerPlayNetworkHandler;
@@ -15,12 +16,15 @@
 import net.minecraft.text.TranslatableText;
 import net.minecraft.util.registry.Registry;
 import org.samo_lego.healthcare.healthbar.HealthbarPreferences;
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
@@ -31,33 +35,55 @@
 public class ServerPlayNetworkHandlerMixin_HealthTag {
     @Shadow public ServerPlayerEntity player;
 
+    @Shadow @Final public ClientConnection connection;
+
+    /**
+     * Dummy handler used for creating modified
+     * packets with health.
+     * This is used instead of real entity datatracker since
+     * we don't want its values to get marked
+     * as non-dirty upon sending the fake packet.
+     */
+    @Unique
+    private final DataTracker healthcare$dummyTracker = new DataTracker(null);
+
+    /**
+     * Gets the current packet being sent and modifies
+     * it accordingly to player's preferences in the packet is
+     * an {@link EntityTrackerUpdateS2CPacket}.
+     *
+     * @param packet packet being sent
+     * @param listener
+     * @param ci
+     */
     @Inject(
             method = "sendPacket(Lnet/minecraft/network/Packet;Lio/netty/util/concurrent/GenericFutureListener;)V",
             at = @At(
                     value = "INVOKE",
                     target = "Lnet/minecraft/network/ClientConnection;send(Lnet/minecraft/network/Packet;Lio/netty/util/concurrent/GenericFutureListener;)V"
-            )
+            ),
+            cancellable = true
     )
     private void onPacketSend(Packet<?> packet, GenericFutureListener<? extends Future<? super Void>> listener, CallbackInfo ci) {
         if(packet instanceof EntityTrackerUpdateS2CPacket) {
-            List<DataTracker.Entry<?>> trackedValues = ((EntityTrackerUpdateS2CPacketAccessor) packet).getTrackedValues();
-
-            Entity entity = this.player.getServerWorld().getEntityById(((EntityTrackerUpdateS2CPacketAccessor) packet).getId());
+            int id = ((EntityTrackerUpdateS2CPacketAccessor) packet).getId();
+            Entity entity = this.player.getServerWorld().getEntityById(id);
 
             if(
-                    entity instanceof LivingEntity &&
+                    entity instanceof LivingEntity living &&
                     ((HealthbarPreferences) this.player).isEnabled() &&
                     !(entity instanceof PlayerEntity) &&
                     !config.blacklistedEntities.contains(Registry.ENTITY_TYPE.getId(entity.getType()).toString())
             ) {
+                List<DataTracker.Entry<?>> trackedValues = new ArrayList<>(((EntityTrackerUpdateS2CPacketAccessor) packet).getTrackedValues());
+
                 // Removing current custom name
                 trackedValues.removeIf(value -> value.getData().getId() == 2);
 
                 // Ensure name is visible only if mob is not too far away
                 boolean visible = (entity.distanceTo(player) < config.activationRange || entity.isCustomNameVisible()) && ((HealthbarPreferences) player).isAlwaysVisible();
                 DataTracker.Entry<Boolean> visibleTag = new DataTracker.Entry<>(EntityAccessor.getNAME_VISIBLE(), visible);
 
-                LivingEntity living = (LivingEntity) entity;
                 float health = living.getHealth();
                 float maxHealth = living.getMaxHealth();
 
@@ -68,7 +94,17 @@ private void onPacketSend(Packet<?> packet, GenericFutureListener<? extends Futu
                 DataTracker.Entry<Optional<Text>> healthTag = new DataTracker.Entry<>(EntityAccessor.getCUSTOM_NAME(), Optional.of(name.append(" ").append(healthbar)));
 
                 Collections.addAll(trackedValues, visibleTag, healthTag);
-                ((EntityTrackerUpdateS2CPacketAccessor) packet).setTrackedValues(trackedValues);
+
+                // Create a new packet in order to not mess with other network handlers
+                // since same packet object is sent to every player
+                EntityTrackerUpdateS2CPacket trackerUpdatePacket = new EntityTrackerUpdateS2CPacket(id, this.healthcare$dummyTracker, false);
+                EntityTrackerUpdateS2CPacketAccessor accessor = (EntityTrackerUpdateS2CPacketAccessor) trackerUpdatePacket;
+
+                accessor.setId(id);
+                accessor.setTrackedValues(trackedValues);
+
+                this.connection.send(trackerUpdatePacket, listener);
+                ci.cancel(); // cancel the original packet going out
             }
         }
     }