Paper/patches/server-remapped/0281-Improve-death-events.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Phoenix616 <mail@moep.tv>
Date: Tue, 21 Aug 2018 01:39:35 +0100
Subject: [PATCH] Improve death events

This adds the ability to cancel the death events and to modify the sound
an entity makes when dying. (In cases were no sound should it will be
called with shouldPlaySound set to false allowing unsilencing of silent
entities)

It makes handling of entity deaths a lot nicer as you no longer need
to listen on the damage event and calculate if the entity dies yourself
to cancel the death which has the benefit of also receiving the dropped
items and experience which is otherwise only properly possible by using
internal code.

diff --git a/src/main/java/net/minecraft/server/level/ServerPlayer.java b/src/main/java/net/minecraft/server/level/ServerPlayer.java
index 5664e292046d4fcdb81340df8cee8d04aa27ca55..75419c866641ab654349cde6ca3fbdef701dd8d9 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayer.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayer.java
@@ -211,6 +211,10 @@ public class ServerPlayer extends Player implements ContainerListener {
     public int latency;
     public boolean wonGame;
     private int containerUpdateDelay; // Paper
+    // Paper start - cancellable death event
+    public boolean queueHealthUpdatePacket = false;
+    public net.minecraft.network.protocol.game.ClientboundSetHealthPacket queuedHealthUpdatePacket;
+    // Paper end
 
     // CraftBukkit start
     public String displayName;
@@ -714,6 +718,15 @@ public class ServerPlayer extends Player implements ContainerListener {
         Component defaultMessage = this.getCombatTracker().getDeathMessage();
 
         org.bukkit.event.entity.PlayerDeathEvent event = CraftEventFactory.callPlayerDeathEvent(this, loot, PaperAdventure.asAdventure(defaultMessage), defaultMessage.getString(), keepInventory); // Paper - Adventure
+        // Paper start - cancellable death event
+        if (event.isCancelled()) {
+            // make compatible with plugins that might have already set the health in an event listener
+            if (this.getHealth() <= 0) {
+                this.setHealth((float) event.getReviveHealth());
+            }
+            return;
+        }
+        // Paper end
 
         // SPIGOT-943 - only call if they have an inventory open
         if (this.containerMenu != this.inventoryMenu) {
@@ -860,8 +873,17 @@ public class ServerPlayer extends Player implements ContainerListener {
                         }
                     }
                 }
-
-                return super.hurt(source, amount);
+                // Paper start - cancellable death events
+                //return super.damageEntity(damagesource, f);
+                this.queueHealthUpdatePacket = true;
+                boolean damaged = super.hurt(source, amount);
+                this.queueHealthUpdatePacket = false;
+                if (this.queuedHealthUpdatePacket != null) {
+                    this.connection.send(this.queuedHealthUpdatePacket);
+                    this.queuedHealthUpdatePacket = null;
+                }
+                return damaged;
+                // Paper end
             }
         }
     }
diff --git a/src/main/java/net/minecraft/world/damagesource/CombatTracker.java b/src/main/java/net/minecraft/world/damagesource/CombatTracker.java
index 8a0863a695bb33698fb3fe6e06599f6f6f47011f..36e665009418d5177016a744eb920fbf99f534fc 100644
--- a/src/main/java/net/minecraft/world/damagesource/CombatTracker.java
+++ b/src/main/java/net/minecraft/world/damagesource/CombatTracker.java
@@ -203,6 +203,7 @@ public class CombatTracker {
         this.nextLocation = null;
     }
 
+    public final void reset() { this.recheckStatus(); } // Paper - OBFHELPER
     public void recheckStatus() {
         int i = this.inCombat ? 300 : 100;
 
diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
index 4503bd65b3454bad94bb7b869f4e72e3121d8a3d..e7fed1f8bb8ffb164ddcdab51f41c369d6e3103d 100644
--- a/src/main/java/net/minecraft/world/entity/Entity.java
+++ b/src/main/java/net/minecraft/world/entity/Entity.java
@@ -1537,6 +1537,7 @@ public abstract class Entity implements Nameable, CommandSource, net.minecraft.s
     }
     // CraftBukkit end
 
+    public final void runKillTrigger(Entity entity, int kills, DamageSource damageSource) { this.awardKillScore(entity, kills, damageSource); } // Paper - OBFHELPER
     public void awardKillScore(Entity killer, int score, DamageSource damageSource) {
         if (killer instanceof ServerPlayer) {
             CriteriaTriggers.ENTITY_KILLED_PLAYER.trigger((ServerPlayer) killer, this, damageSource);
@@ -2441,6 +2442,7 @@ public abstract class Entity implements Nameable, CommandSource, net.minecraft.s
         this.fallDistance = 0.0F;
     }
 
+    public final void onKill(ServerLevel worldserver, net.minecraft.world.entity.LivingEntity entityLiving) { this.killed(worldserver, entityLiving); } // Paper - OBFHELPER
     public void killed(ServerLevel worldserver, net.minecraft.world.entity.LivingEntity entityliving) {}
 
     protected void moveTowardsClosestSpace(double x, double y, double z) {
diff --git a/src/main/java/net/minecraft/world/entity/LivingEntity.java b/src/main/java/net/minecraft/world/entity/LivingEntity.java
index 2e25cb2a04d150d3154bf0d7f0eccb97e65ff53e..7a2292e6907a2ae2026bd7243e864bd8300ecafa 100644
--- a/src/main/java/net/minecraft/world/entity/LivingEntity.java
+++ b/src/main/java/net/minecraft/world/entity/LivingEntity.java
@@ -186,7 +186,7 @@ public abstract class LivingEntity extends Entity {
     protected float animStep;
     protected float animStepO;
     protected float rotOffs;
-    protected int deathScore;
+    protected int deathScore;protected int getKillCount() { return this.deathScore; } // Paper - OBFHELPER
     public float lastHurt;
     protected boolean jumping;
     public float xxa;
@@ -230,6 +230,7 @@ public abstract class LivingEntity extends Entity {
     public Set<UUID> collidableExemptions = new HashSet<>();
     public boolean canPickUpLoot;
     public org.bukkit.craftbukkit.entity.CraftLivingEntity getBukkitLivingEntity() { return (org.bukkit.craftbukkit.entity.CraftLivingEntity) super.getBukkitEntity(); } // Paper
+    public boolean silentDeath = false; // Paper - mark entity as dying silently for cancellable death event
 
     @Override
     public float getBukkitYaw() {
@@ -1345,13 +1346,17 @@ public abstract class LivingEntity extends Entity {
             if (knockbackCancelled) this.level.broadcastEntityEvent(this, (byte) 2); // Paper - Disable explosion knockback
             if (this.isDeadOrDying()) {
                 if (!this.checkTotemDeathProtection(source)) {
-                    SoundEvent soundeffect = this.getDeathSound();
+                    // Paper start - moved into CraftEventFactory event caller for cancellable death event
+                    //SoundEffect soundeffect = this.getSoundDeath();
 
-                    if (flag1 && soundeffect != null) {
-                        this.playSound(soundeffect, this.getSoundVolume(), this.getVoicePitch());
-                    }
+//                    if (flag1 && soundeffect != null) {
+//                        this.playSound(soundeffect, this.getSoundVolume(), this.dH());
+//                    }
+                    this.silentDeath = !flag1; // mark entity as dying silently
+                    // Paper end
 
                     this.die(source);
+                    this.silentDeath = false; // Paper - cancellable death event - reset to default
                 }
             } else if (flag1) {
                 this.playHurtSound(source);
@@ -1490,27 +1495,48 @@ public abstract class LivingEntity extends Entity {
             Entity entity = source.getEntity();
             LivingEntity entityliving = this.getKillCredit();
 
-            if (this.deathScore >= 0 && entityliving != null) {
-                entityliving.awardKillScore(this, this.deathScore, source);
+            /* // Paper - move down to make death event cancellable - this is the runKillTrigger below
+            if (this.aO >= 0 && entityliving != null) {
+                entityliving.a(this, this.aO, damagesource);
             }
 
             if (this.isSleeping()) {
-                this.stopSleeping();
+                this.entityWakeup();
             }
+            */ // Paper
 
             this.dead = true;
-            this.getCombatTracker().recheckStatus();
+            // this.getCombatTracker().g(); // Paper - moved into if below as .reset()
             if (this.level instanceof ServerLevel) {
                 if (entity != null) {
-                    entity.killed((ServerLevel) this.level, this);
+                    // entity.a((WorldServer) this.world, this); // Paper - move below into if for onKill
                 }
 
-                this.dropAllDeathLoot(source);
+                // Paper start
+                org.bukkit.event.entity.EntityDeathEvent deathEvent = this.d(source);
+                if (deathEvent == null || !deathEvent.isCancelled()) {
+                    if (this.getKillCount() >= 0 && entityliving != null) {
+                        entityliving.runKillTrigger(this, this.getKillCount(), source);
+                    }
+                    if (this.isSleeping()) {
+                        this.stopSleeping();
+                    }
+                    this.getCombatTracker().reset();
+                    if (entity != null) {
+                        entity.onKill((ServerLevel) this.level, this);
+                    }
+                } else {
+                    this.dead = false;
+                    this.setHealth((float) deathEvent.getReviveHealth());
+                }
+                // Paper end
                 this.createWitherRose(entityliving);
             }
 
+            if (this.dead) { // Paper
             this.level.broadcastEntityEvent(this, (byte) 3);
             this.setPose(Pose.DYING);
+            } // Paper
         }
     }
 
@@ -1518,7 +1544,7 @@ public abstract class LivingEntity extends Entity {
         if (!this.level.isClientSide) {
             boolean flag = false;
 
-            if (adversary instanceof WitherBoss) {
+            if (this.dead && adversary instanceof WitherBoss) { // Paper
                 if (this.level.getGameRules().getBoolean(GameRules.RULE_MOBGRIEFING)) {
                     BlockPos blockposition = this.blockPosition();
                     BlockState iblockdata = Blocks.WITHER_ROSE.defaultBlockState();
@@ -1546,8 +1572,9 @@ public abstract class LivingEntity extends Entity {
         }
     }
 
-    protected void dropAllDeathLoot(DamageSource source) {
-        Entity entity = source.getEntity();
+    protected org.bukkit.event.entity.EntityDeathEvent processDeath(DamageSource damagesource) { return d(damagesource); } // Paper - OBFHELPER
+    protected org.bukkit.event.entity.EntityDeathEvent d(DamageSource damagesource) { // Paper
+        Entity entity = damagesource.getEntity();
         int i;
 
         if (entity instanceof net.minecraft.world.entity.player.Player) {
@@ -1560,19 +1587,22 @@ public abstract class LivingEntity extends Entity {
 
         this.dropEquipment(); // CraftBukkit - from below
         if (this.shouldDropLoot() && this.level.getGameRules().getBoolean(GameRules.RULE_DOMOBLOOT)) {
-            this.dropFromLootTable(source, flag);
-            this.dropCustomDeathLoot(source, i, flag);
+            this.dropFromLootTable(damagesource, flag);
+            this.dropCustomDeathLoot(damagesource, i, flag);
         }
         // CraftBukkit start - Call death event
-        CraftEventFactory.callEntityDeathEvent(this, this.drops);
+        org.bukkit.event.entity.EntityDeathEvent deathEvent = CraftEventFactory.callEntityDeathEvent(this, this.drops); // Paper
+        this.postDeathDropItems(deathEvent); // Paper
         this.drops = new ArrayList<>();
         // CraftBukkit end
 
         // this.dropInventory();// CraftBukkit - moved up
         this.dropExperience();
+        return deathEvent; // Paper
     }
 
     protected void dropEquipment() {}
+    protected void postDeathDropItems(org.bukkit.event.entity.EntityDeathEvent event) {} // Paper - method for post death logic that cannot be ran before the event is potentially cancelled
 
     // CraftBukkit start
     public int getExpReward() {
@@ -1657,6 +1687,7 @@ public abstract class LivingEntity extends Entity {
         return SoundEvents.GENERIC_HURT;
     }
 
+    public final SoundEvent getDeathSoundEffect() { return this.getDeathSound(); } // Paper - OBFHELPER
     @Nullable
     protected SoundEvent getDeathSound() {
         return SoundEvents.GENERIC_DEATH;
@@ -2193,10 +2224,12 @@ public abstract class LivingEntity extends Entity {
 
     }
 
+    public final float getDeathSoundVolume() { return this.getSoundVolume(); } // Paper - OBFHELPER
     protected float getSoundVolume() {
         return 1.0F;
     }
 
+    public float getSoundPitch() { return getVoicePitch();} // Paper - OBFHELPER
     protected float getVoicePitch() {
         return this.isBaby() ? (this.random.nextFloat() - this.random.nextFloat()) * 0.2F + 1.5F : (this.random.nextFloat() - this.random.nextFloat()) * 0.2F + 1.0F;
     }
diff --git a/src/main/java/net/minecraft/world/entity/animal/Fox.java b/src/main/java/net/minecraft/world/entity/animal/Fox.java
index c2d98222f575d7383e4c040730f6d531bdb0d7b6..46792914f574800c893eb197fa7b3b87ce7e500b 100644
--- a/src/main/java/net/minecraft/world/entity/animal/Fox.java
+++ b/src/main/java/net/minecraft/world/entity/animal/Fox.java
@@ -647,15 +647,25 @@ public class Fox extends Animal {
     }
 
     @Override
-    protected void dropAllDeathLoot(DamageSource source) {
-        ItemStack itemstack = this.getItemBySlot(EquipmentSlot.MAINHAND);
+    protected org.bukkit.event.entity.EntityDeathEvent d(DamageSource damagesource) { // Paper
+        ItemStack itemstack = this.getItemBySlot(EquipmentSlot.MAINHAND).copy(); // Paper
+
+        // Paper start - Cancellable death event
+        org.bukkit.event.entity.EntityDeathEvent deathEvent = super.d(damagesource);
+
+        // Below is code to drop
+
+        if (deathEvent == null || deathEvent.isCancelled()) {
+            return deathEvent;
+        }
+        // Paper end
 
         if (!itemstack.isEmpty()) {
             this.spawnAtLocation(itemstack);
             this.setItemSlot(EquipmentSlot.MAINHAND, ItemStack.EMPTY);
         }
 
-        super.dropAllDeathLoot(source);
+        return deathEvent; // Paper
     }
 
     public static boolean isPathClear(Fox fox, LivingEntity chasedEntity) {
diff --git a/src/main/java/net/minecraft/world/entity/animal/horse/AbstractChestedHorse.java b/src/main/java/net/minecraft/world/entity/animal/horse/AbstractChestedHorse.java
index 34a9843267ef739e5889791fb4899fabe1f864bc..63723044ae6c607e6d36bc0b0c6b525037df34b2 100644
--- a/src/main/java/net/minecraft/world/entity/animal/horse/AbstractChestedHorse.java
+++ b/src/main/java/net/minecraft/world/entity/animal/horse/AbstractChestedHorse.java
@@ -68,11 +68,19 @@ public abstract class AbstractChestedHorse extends AbstractHorse {
                 this.spawnAtLocation((ItemLike) Blocks.CHEST);
             }
 
-            this.setChest(false);
+            //this.setCarryingChest(false); // Paper - moved to post death logic
         }
 
     }
 
+    // Paper start
+    protected void postDeathDropItems(org.bukkit.event.entity.EntityDeathEvent event) {
+        if (this.hasChest() && (event == null || !event.isCancelled())) {
+            this.setChest(false);
+        }
+    }
+    // Paper end
+
     @Override
     public void addAdditionalSaveData(CompoundTag tag) {
         super.addAdditionalSaveData(tag);
diff --git a/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java b/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java
index 2994eee1d381af2c9ff3649dd48a2ae14c38c9d7..33d51852ed6fe3f5adcdecf8f405a23689f4265a 100644
--- a/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java
+++ b/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java
@@ -610,7 +610,7 @@ public class ArmorStand extends LivingEntity {
                 this.armorItems.set(i, ItemStack.EMPTY);
             }
         }
-        this.dropAllDeathLoot(damageSource); // CraftBukkit - moved from above
+        this.d(damageSource); // CraftBukkit - moved from above
 
     }
 
@@ -742,7 +742,8 @@ public class ArmorStand extends LivingEntity {
 
     @Override
     public void kill() {
-        org.bukkit.craftbukkit.event.CraftEventFactory.callEntityDeathEvent(this, drops); // CraftBukkit - call event
+        org.bukkit.event.entity.EntityDeathEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callEntityDeathEvent(this, drops); // CraftBukkit - call event // Paper - make cancellable
+        if (event.isCancelled()) return; // Paper - make cancellable
         this.remove();
     }
 
diff --git a/src/main/java/net/minecraft/world/entity/player/Player.java b/src/main/java/net/minecraft/world/entity/player/Player.java
index 14d5acff198338c68162e33d4a90f74be77cb15f..3aadc4ab5fe7b2ee9e20e0789ddcfe750599972f 100644
--- a/src/main/java/net/minecraft/world/entity/player/Player.java
+++ b/src/main/java/net/minecraft/world/entity/player/Player.java
@@ -581,7 +581,7 @@ public abstract class Player extends LivingEntity {
         super.die(source);
         this.reapplyPosition();
         if (!this.isSpectator()) {
-            this.dropAllDeathLoot(source);
+            this.d(source);
         }
 
         if (source != null) {
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
index ee823c4ed5b9fcfaa900b470c582435f0b909ebc..a3e65028d3e0c09a65cd9c28b037fe01a2ed1d76 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
@@ -1836,7 +1836,15 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
     }
 
     public void sendHealthUpdate() {
-        getHandle().connection.send(new ClientboundSetHealthPacket(getScaledHealth(), getHandle().getFoodData().getFoodLevel(), getHandle().getFoodData().getSaturationLevel()));
+        // Paper start - cancellable death event
+        //getHandle().playerConnection.sendPacket(new PacketPlayOutUpdateHealth(getScaledHealth(), getHandle().getFoodData().getFoodLevel(), getHandle().getFoodData().getSaturationLevel()));
+        ClientboundSetHealthPacket packet = new ClientboundSetHealthPacket(getScaledHealth(), getHandle().getFoodData().getFoodLevel(), getHandle().getFoodData().getSaturationLevel());
+        if (this.getHandle().queueHealthUpdatePacket) {
+            this.getHandle().queuedHealthUpdatePacket = packet;
+        } else {
+            this.getHandle().connection.send(packet);
+        }
+        // Paper end
     }
 
     public void injectScaledMaxHealth(Collection<AttributeInstance> collection, boolean force) {
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index 1877267344df1ff5b4de6a4e0c239f488cd52c1f..e696d2e52532df25d74a1f559e2c9ca0f3d5058d 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -18,6 +18,8 @@ import net.minecraft.network.protocol.game.ServerboundContainerClosePacket;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.sounds.SoundEvent;
+import net.minecraft.sounds.SoundSource;
 import net.minecraft.util.Unit;
 import net.minecraft.world.Container;
 import net.minecraft.world.InteractionHand;
@@ -793,9 +795,16 @@ public class CraftEventFactory {
     public static EntityDeathEvent callEntityDeathEvent(net.minecraft.world.entity.LivingEntity victim, List<org.bukkit.inventory.ItemStack> drops) {
         CraftLivingEntity entity = (CraftLivingEntity) victim.getBukkitEntity();
         EntityDeathEvent event = new EntityDeathEvent(entity, drops, victim.getExpReward());
+        populateFields(victim, event); // Paper - make cancellable
         CraftWorld world = (CraftWorld) entity.getWorld();
         Bukkit.getServer().getPluginManager().callEvent(event);
 
+        // Paper start - make cancellable
+        if (event.isCancelled()) {
+            return event;
+        }
+        playDeathSound(victim, event);
+        // Paper end
         victim.expToDrop = event.getDroppedExp();
 
         for (org.bukkit.inventory.ItemStack stack : event.getDrops()) {
@@ -811,8 +820,15 @@ public class CraftEventFactory {
         CraftPlayer entity = victim.getBukkitEntity();
         PlayerDeathEvent event = new PlayerDeathEvent(entity, drops, victim.getExpReward(), 0, deathMessage, stringDeathMessage); // Paper - Adventure
         event.setKeepInventory(keepInventory);
+        populateFields(victim, event); // Paper - make cancellable
         org.bukkit.World world = entity.getWorld();
         Bukkit.getServer().getPluginManager().callEvent(event);
+        // Paper start - make cancellable
+        if (event.isCancelled()) {
+            return event;
+        }
+        playDeathSound(victim, event);
+        // Paper end
 
         victim.keepLevel = event.getKeepLevel();
         victim.newLevel = event.getNewLevel();
@@ -829,6 +845,31 @@ public class CraftEventFactory {
         return event;
     }
 
+    // Paper start - helper methods for making death event cancellable
+    // Add information to death event
+    private static void populateFields(net.minecraft.world.entity.LivingEntity victim, EntityDeathEvent event) {
+        event.setReviveHealth(event.getEntity().getAttribute(org.bukkit.attribute.Attribute.GENERIC_MAX_HEALTH).getValue());
+        event.setShouldPlayDeathSound(!victim.silentDeath && !victim.isSilent());
+        SoundEvent soundEffect = victim.getDeathSoundEffect();
+        event.setDeathSound(soundEffect != null ? org.bukkit.craftbukkit.CraftSound.getBukkit(soundEffect) : null);
+        event.setDeathSoundCategory(org.bukkit.SoundCategory.valueOf(victim.getSoundSource().name()));
+        event.setDeathSoundVolume(victim.getDeathSoundVolume());
+        event.setDeathSoundPitch(victim.getSoundPitch());
+    }
+
+    // Play death sound manually
+    private static void playDeathSound(net.minecraft.world.entity.LivingEntity victim, EntityDeathEvent event) {
+        if (event.shouldPlayDeathSound() && event.getDeathSound() != null && event.getDeathSoundCategory() != null) {
+            net.minecraft.world.entity.player.Player source = victim instanceof net.minecraft.world.entity.player.Player ? (net.minecraft.world.entity.player.Player) victim : null;
+            double x = event.getEntity().getLocation().getX();
+            double y = event.getEntity().getLocation().getY();
+            double z = event.getEntity().getLocation().getZ();
+            SoundEvent soundEffect = org.bukkit.craftbukkit.CraftSound.getSoundEffect(event.getDeathSound());
+            SoundSource soundCategory = SoundSource.valueOf(event.getDeathSoundCategory().name());
+            victim.level.playSound(source, x, y, z, soundEffect, soundCategory, event.getDeathSoundVolume(), event.getDeathSoundPitch());
+        }
+    }
+    // Paper end
     /**
      * Server methods
      */