fix: populate damage event modifiers on server only

Enchantments can only reference a ServerLevel, so we keep the injection
points in Player, but will override their injection points on
ServerPlayer. This will still enable the event being thrown on the
client, but only add the DamageModifiers on the server (where they
belong).

Author: gabizou

src/mixins/java/org/spongepowered/common/mixin/core/server/level/ServerPlayerMixin_Attack_impl.java

@@ -0,0 +1,78 @@
+/*
+ * This file is part of Sponge, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) SpongePowered <https://www.spongepowered.org>
+ * Copyright (c) contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package org.spongepowered.common.mixin.core.server.level;
+
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.entity.player.Player;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import org.spongepowered.common.mixin.core.world.entity.player.PlayerMixin_Attack_Impl;
+import org.spongepowered.common.util.DamageEventUtil;
+
+import java.util.ArrayList;
+
+@Mixin(value = ServerPlayer.class, priority = 900)
+public abstract class ServerPlayerMixin_Attack_impl extends PlayerMixin_Attack_Impl {
+
+    @Override
+    protected void attackImpl$enchanttDamageFunc(Entity $$0, CallbackInfo ci) {
+        final var weapon = this.attackImpl$attack.weapon();
+        // this.getEnchantedDamage(targetEntity, damage, damageSource) - damage;
+        final var functions = DamageEventUtil.createAttackEnchantmentFunction(weapon, this.attackImpl$attack.target(), this.attackImpl$attack.dmgSource());
+        final var separateFunc = DamageEventUtil.provideSeparateEnchantmentFromBaseDamageFunction(this.attackImpl$attack.baseDamage(), weapon);
+        // enchantmentDamage *= attackStrength;
+        final var strengthScaleFunc = DamageEventUtil.provideCooldownEnchantmentStrengthFunction(weapon, this.attackImpl$attack.strengthScale());
+
+        this.attackImpl$attack.functions().addAll(functions);
+        this.attackImpl$attack.functions().add(separateFunc);
+        this.attackImpl$attack.functions().add(strengthScaleFunc);
+    }
+
+    @Override
+    protected double attackImpl$beforeSweepHurt(Player instance, Entity sweepTarget) {
+        final var distanceToSqr = instance.distanceToSqr(sweepTarget);
+        if (!(distanceToSqr < 9.0)) {
+            return distanceToSqr; // Too far - no event
+        }
+
+        final var mainAttack = this.attackImpl$attack;
+        final var mainAttackDamage = this.attackImpl$finalDamageAmounts.getOrDefault("minecraft:attack_damage", 0.0).floatValue();
+
+        var sweepAttack = new DamageEventUtil.Attack<>(mainAttack.sourceEntity(), sweepTarget, mainAttack.weapon(), mainAttack.dmgSource(), mainAttack.strengthScale(), 1, new ArrayList<>());
+        // float sweepBaseDamage = 1.0F + (float)this.getAttributeValue(Attributes.SWEEPING_DAMAGE_RATIO) * attackDamage;
+        sweepAttack.functions().add(DamageEventUtil.provideSweepingDamageRatioFunction(mainAttack.weapon(), mainAttack.sourceEntity(), mainAttackDamage));
+        // float sweepFullDamage = this.getEnchantedDamage(sweepTarget, sweepBaseDamage, $$3) * strengthScale;
+        sweepAttack.functions().addAll(DamageEventUtil.createAttackEnchantmentFunction(mainAttack.weapon(), sweepTarget, mainAttack.dmgSource()));
+        sweepAttack.functions().add(DamageEventUtil.provideCooldownEnchantmentStrengthFunction(mainAttack.weapon(), mainAttack.strengthScale()));
+
+        this.attackImpl$attackEvent = DamageEventUtil.callPlayerAttackEntityEvent(sweepAttack, 1.0F);
+        if (attackImpl$attackEvent.isCancelled()) {
+            return Double.MAX_VALUE;
+        }
+
+        return distanceToSqr;
+    }
+}

src/mixins/java/org/spongepowered/common/mixin/core/world/entity/LivingEntityMixin_Attack_Impl.java

@@ -243,7 +243,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
     }
 
     @Inject(method = "actuallyHurt", at = @At(value = "INVOKE",target = "Lnet/minecraft/world/entity/LivingEntity;getDamageAfterArmorAbsorb(Lnet/minecraft/world/damagesource/DamageSource;F)F"))
-    public void attackImpl$startActuallyHurt(DamageSource damageSource, float originalDamage, CallbackInfo ci) {
+    protected void attackImpl$startActuallyHurt(DamageSource damageSource, float originalDamage, CallbackInfo ci) {
         // TODO check for direct call?
         this.attackImpl$actuallyHurt = new DamageEventUtil.ActuallyHurt((LivingEntity) (Object) this, new ArrayList<>(), damageSource, originalDamage);
     }
@@ -254,7 +254,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
      */
     @Redirect(method = "getDamageAfterArmorAbsorb",
         at = @At(value = "INVOKE", target = "Lnet/minecraft/world/entity/LivingEntity;hurtArmor(Lnet/minecraft/world/damagesource/DamageSource;F)V"))
-    public void attackImpl$onDamageAfterArmorAbsorb(final LivingEntity instance, final DamageSource $$0, final float $$1) {
+    protected void attackImpl$onDamageAfterArmorAbsorb(final LivingEntity instance, final DamageSource $$0, final float $$1) {
         if (this.attackImpl$actuallyHurt != null) {
             // prevents this.hurtArmor($$0, $$1);
             // $$1 = CombatRules.getDamageAfterAbsorb(this, $$1, $$0, (float)this.getArmorValue(), (float)this.getAttributeValue(Attributes.ARMOR_TOUGHNESS));
@@ -268,7 +268,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
      */
     @Inject(method = "getDamageAfterMagicAbsorb",
         at = @At(value = "INVOKE", target = "Lnet/minecraft/world/entity/LivingEntity;getEffect(Lnet/minecraft/core/Holder;)Lnet/minecraft/world/effect/MobEffectInstance;"))
-    public void attackImpl$onDamageAfterMagicAbsorb(final DamageSource $$0, final float $$1, final CallbackInfoReturnable<Float> cir) {
+    protected void attackImpl$onDamageAfterMagicAbsorb(final DamageSource $$0, final float $$1, final CallbackInfoReturnable<Float> cir) {
         if (this.attackImpl$actuallyHurt != null) {
             var func = DamageEventUtil.createResistanceModifier(this.attackImpl$actuallyHurt.entity());
             this.attackImpl$actuallyHurt.functions().add(func);
@@ -281,7 +281,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
      */
     @Redirect(method = "getDamageAfterMagicAbsorb",
         at = @At(value = "INVOKE", target = "Lnet/minecraft/world/damagesource/CombatRules;getDamageAfterMagicAbsorb(FF)F"))
-    public float attackImpl$onDetDamageProtection(final float damage, final float protection) {
+    protected float attackImpl$onDetDamageProtection(final float damage, final float protection) {
         if (this.attackImpl$actuallyHurt != null) {
             var func = DamageEventUtil.createEnchantmentModifiers(this.attackImpl$actuallyHurt.entity(), protection);
             this.attackImpl$actuallyHurt.functions().add(func);
@@ -295,7 +295,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
      * Then calls the DamageEntityEvent
      */
     @Inject(method = "setAbsorptionAmount", cancellable = true, at = @At("HEAD"))
-    public void attackImpl$onSetAbsorptionAmount(final float newAmount, final CallbackInfo ci) {
+    protected void attackImpl$onSetAbsorptionAmount(final float newAmount, final CallbackInfo ci) {
         if (this.attackImpl$actuallyHurt != null) {
             ci.cancel(); // Always cancel this
             var oldAmount = this.shadow$getAbsorptionAmount();
@@ -331,7 +331,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
     @ModifyVariable(method = "actuallyHurt", ordinal = 0,
         at = @At(value = "INVOKE", target = "Lnet/minecraft/world/entity/LivingEntity;setAbsorptionAmount(F)V",
             ordinal = 0, shift = At.Shift.AFTER), argsOnly = true)
-    public float attackImpl$setFinalDamage(final float value) {
+    protected float attackImpl$setFinalDamage(final float value) {
         if (this.attackImpl$actuallyHurtResult.event().isCancelled()) {
             return 0;
         }
@@ -388,7 +388,7 @@ public abstract class LivingEntityMixin_Attack_Impl extends EntityMixin implemen
      * also reverts {@link #attackImpl$beforeActuallyHurt}
      */
     @Inject(method = "actuallyHurt", at = @At("RETURN"))
-    public void attackImpl$cleanupActuallyHurt(final DamageSource $$0, final float $$1, final CallbackInfo ci) {
+    protected void attackImpl$cleanupActuallyHurt(final DamageSource $$0, final float $$1, final CallbackInfo ci) {
         this.attackImpl$handlePostDamage();
         this.attackImpl$actuallyHurt = null;
         this.attackImpl$actuallyHurtResult = null;