Add support for /tick rate on Fabric

common/src/main/java/me/caseload/knockbacksync/player/PlayerData.java

@@ -34,6 +34,7 @@ public class PlayerData {
     public static final long PING_OFFSET = 25;
     private static final int PLUGIN_IDENTIFIER = 0x80000000; // Bit 31 set to 1 (negative)
     private static final int ID_MASK = 0x7FFF; // 15-bit mask
+    public static float TICK_RATE = 20.0F;
     private static Field playerField;
 
     static {
@@ -185,7 +186,7 @@ public boolean isOnGround(double verticalVelocity) {
         if (tFall == -1)
             return false; // reached the max tick limit, not safe to predict
 
-        return getEstimatedPing() >= tMax + tFall / 20.0 * 1000 && gDist <= 1.3;
+        return getEstimatedPing() >= tMax + tFall / TICK_RATE * 1000 && gDist <= 1.3;
     }
 
     /**

fabric/src/main/java/me/caseload/knockbacksync/KnockbackSyncFabric.java

@@ -6,6 +6,7 @@
 import me.caseload.knockbacksync.listener.fabric.FabricPlayerDamageListener;
 import me.caseload.knockbacksync.listener.fabric.FabricPlayerJoinQuitListener;
 import me.caseload.knockbacksync.listener.fabric.FabricPlayerKnockbackListener;
+import me.caseload.knockbacksync.listener.fabric.FabricTickRateChangeListener;
 import me.caseload.knockbacksync.permission.FabricPermissionChecker;
 import me.caseload.knockbacksync.permission.PermissionChecker;
 import me.caseload.knockbacksync.scheduler.FabricSchedulerAdapter;
@@ -87,6 +88,7 @@ protected void registerPlatformListeners() {
             new FabricPlayerJoinQuitListener().register();
             new FabricPlayerDamageListener().register();
             new FabricPlayerKnockbackListener().register();
+            new FabricTickRateChangeListener().register();
         }
 
         @Override

fabric/src/main/java/me/caseload/knockbacksync/callback/PlayerVelocityCallback.java → fabric/src/main/java/me/caseload/knockbacksync/callback/PlayerVelocityEvent.java

@@ -6,10 +6,10 @@
 import net.minecraft.world.InteractionResult;
 import net.minecraft.world.phys.Vec3;
 
-public interface PlayerVelocityCallback {
-    Event<PlayerVelocityCallback> EVENT = EventFactory.createArrayBacked(PlayerVelocityCallback.class,
+public interface PlayerVelocityEvent {
+    Event<PlayerVelocityEvent> EVENT = EventFactory.createArrayBacked(PlayerVelocityEvent.class,
             (listeners) -> (player, velocity) -> {
-                for (PlayerVelocityCallback listener : listeners) {
+                for (PlayerVelocityEvent listener : listeners) {
                     InteractionResult result = listener.onVelocityChange(player, velocity);
 
                     if (result != InteractionResult.PASS) {

fabric/src/main/java/me/caseload/knockbacksync/callback/TickRateChangeEvent.java

@@ -0,0 +1,15 @@
+package me.caseload.knockbacksync.callback;
+
+import net.fabricmc.fabric.api.event.Event;
+import net.fabricmc.fabric.api.event.EventFactory;
+
+public interface TickRateChangeEvent {
+    Event<TickRateChangeEvent> EVENT = EventFactory.createArrayBacked(TickRateChangeEvent.class,
+            (listeners) -> (oldTickRate, newTickRate) -> {
+                for (TickRateChangeEvent listener : listeners) {
+                    listener.onTickRateChange(oldTickRate, newTickRate);
+                }
+            });
+
+    void onTickRateChange(float oldTickRate, float newTickRate);
+}

fabric/src/main/java/me/caseload/knockbacksync/listener/fabric/FabricPlayerKnockbackListener.java

@@ -1,7 +1,7 @@
 package me.caseload.knockbacksync.listener.fabric;
 
 import com.github.retrooper.packetevents.util.Vector3d;
-import me.caseload.knockbacksync.callback.PlayerVelocityCallback;
+import me.caseload.knockbacksync.callback.PlayerVelocityEvent;
 import me.caseload.knockbacksync.listener.PlayerKnockbackListener;
 import me.caseload.knockbacksync.player.FabricPlayer;
 import net.minecraft.world.InteractionResult;
@@ -11,7 +11,7 @@
 public class FabricPlayerKnockbackListener extends PlayerKnockbackListener {
 
     public void register() {
-        PlayerVelocityCallback.EVENT.register((player, velocity) -> {
+        PlayerVelocityEvent.EVENT.register((player, velocity) -> {
             DamageSource lastDamageSource = player.getLastDamageSource();
             if (lastDamageSource == null)
                 return InteractionResult.PASS;

fabric/src/main/java/me/caseload/knockbacksync/listener/fabric/FabricTickRateChangeListener.java

@@ -0,0 +1,14 @@
+package me.caseload.knockbacksync.listener.fabric;
+
+import me.caseload.knockbacksync.callback.TickRateChangeEvent;
+import me.caseload.knockbacksync.player.PlayerData;
+
+public class FabricTickRateChangeListener {
+    public void register() {
+        TickRateChangeEvent.EVENT.register((oldTickRate, newTickRate) -> {
+            if (oldTickRate != newTickRate) {
+                PlayerData.TICK_RATE = newTickRate;
+            }
+        });
+    }
+}

fabric/src/main/java/me/caseload/knockbacksync/mixin/PlayerMixin.java

@@ -1,6 +1,6 @@
 package me.caseload.knockbacksync.mixin;
 
-import me.caseload.knockbacksync.callback.PlayerVelocityCallback;
+import me.caseload.knockbacksync.callback.PlayerVelocityEvent;
 import net.minecraft.network.protocol.game.ClientboundSetEntityMotionPacket;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.InteractionResult;
@@ -20,7 +20,7 @@ private void onAttack(Entity target, CallbackInfo ci) {
         if (target instanceof ServerPlayer serverPlayer && target.hurtMarked) {
             Vec3 velocity = target.getDeltaMovement();
 
-            InteractionResult result = PlayerVelocityCallback.EVENT.invoker().onVelocityChange(serverPlayer, velocity);
+            InteractionResult result = PlayerVelocityEvent.EVENT.invoker().onVelocityChange(serverPlayer, velocity);
 
             if (result == InteractionResult.FAIL) {
                 target.hurtMarked = false;

fabric/src/main/java/me/caseload/knockbacksync/mixin/ServerEntityMixin.java

@@ -1,6 +1,6 @@
 package me.caseload.knockbacksync.mixin;
 
-import me.caseload.knockbacksync.callback.PlayerVelocityCallback;
+import me.caseload.knockbacksync.callback.PlayerVelocityEvent;
 import net.minecraft.server.level.ServerEntity;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.InteractionResult;
@@ -27,7 +27,7 @@ private void onSendChanges(CallbackInfo ci) {
             ServerPlayer player = (ServerPlayer) this.entity;
             Vec3 velocity = player.getDeltaMovement();
 
-            InteractionResult result = PlayerVelocityCallback.EVENT.invoker().onVelocityChange(player, velocity);
+            InteractionResult result = PlayerVelocityEvent.EVENT.invoker().onVelocityChange(player, velocity);
 
             if (result == InteractionResult.FAIL) {
                 this.entity.hurtMarked = false;

fabric/src/main/java/me/caseload/knockbacksync/mixin/TickRateManagerMixin.java

@@ -0,0 +1,22 @@
+package me.caseload.knockbacksync.mixin;
+
+import me.caseload.knockbacksync.callback.TickRateChangeEvent;
+import org.spongepowered.asm.mixin.Mixin;
+
+import net.minecraft.world.TickRateManager;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(TickRateManager.class)
+public class TickRateManagerMixin {
+    @Shadow
+    protected float tickrate;
+
+    @Inject(method = "setTickRate", at = @At("HEAD"))
+    private void onSetTickRate(float tickRate, CallbackInfo ci) {
+        float oldTickRate = this.tickrate;
+        TickRateChangeEvent.EVENT.invoker().onTickRateChange(oldTickRate, tickRate);
+    }
+}

fabric/src/main/resources/knockbacksync.mixins.json

@@ -5,7 +5,8 @@
   "compatibilityLevel": "JAVA_21",
   "mixins": [
     "PlayerMixin",
-    "ServerEntityMixin"
+    "ServerEntityMixin",
+    "TickRateManagerMixin"
   ],
   "injectors": {
     "defaultRequire": 1