From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: William Blake Galbreath <blake.galbreath@gmail.com>
Date: Sat, 22 Feb 2020 15:54:08 -0600
Subject: [PATCH] Item entity immunities


diff --git a/src/main/java/net/minecraft/server/level/ServerEntity.java b/src/main/java/net/minecraft/server/level/ServerEntity.java
index 5a2f7f7cf79dcbb996574e18cad86ebb54bd718e..dfd09004063a8d8d93357633c8d23b6acff67b73 100644
--- a/src/main/java/net/minecraft/server/level/ServerEntity.java
+++ b/src/main/java/net/minecraft/server/level/ServerEntity.java
@@ -77,7 +77,7 @@ public class ServerEntity {
     @Nullable
     private List<SynchedEntityData.DataValue<?>> trackedDataValues;
     // CraftBukkit start
-    private final Set<ServerPlayerConnection> trackedPlayers;
+    public final Set<ServerPlayerConnection> trackedPlayers; // Purpur - private -> public
 
     public ServerEntity(ServerLevel worldserver, Entity entity, int i, boolean flag, Consumer<Packet<?>> consumer, Set<ServerPlayerConnection> trackedPlayers) {
         this.trackedPlayers = trackedPlayers;
diff --git a/src/main/java/net/minecraft/world/entity/item/ItemEntity.java b/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
index ea0d9335446b20073b9aafb9de453097355db79c..499646ad26d148953abf241d90e053870fedb708 100644
--- a/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
+++ b/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
@@ -64,6 +64,12 @@ public class ItemEntity extends Entity implements TraceableEntity {
     public boolean canMobPickup = true; // Paper - Item#canEntityPickup
     private int despawnRate = -1; // Paper - Alternative item-despawn-rate
     public net.kyori.adventure.util.TriState frictionState = net.kyori.adventure.util.TriState.NOT_SET; // Paper - Friction API
+    // Purpur start
+    public boolean immuneToCactus = false;
+    public boolean immuneToExplosion = false;
+    public boolean immuneToFire = false;
+    public boolean immuneToLightning = false;
+    // Purpur end
 
     public ItemEntity(EntityType<? extends ItemEntity> type, Level world) {
         super(type, world);
@@ -372,7 +378,16 @@ public class ItemEntity extends Entity implements TraceableEntity {
 
     @Override
     public boolean hurt(DamageSource source, float amount) {
-        if (this.isInvulnerableTo(source)) {
+        // Purpur start
+        if (
+            (immuneToCactus && source.is(net.minecraft.world.damagesource.DamageTypes.CACTUS)) ||
+            (immuneToFire && (source.is(DamageTypeTags.IS_FIRE) || source.is(net.minecraft.world.damagesource.DamageTypes.ON_FIRE) || source.is(net.minecraft.world.damagesource.DamageTypes.IN_FIRE))) ||
+            (immuneToLightning && source.is(net.minecraft.world.damagesource.DamageTypes.LIGHTNING_BOLT)) ||
+            (immuneToExplosion && source.is(DamageTypeTags.IS_EXPLOSION))
+        ) {
+            return false;
+        } else if (this.isInvulnerableTo(source)) {
+        // Purpur end
             return false;
         } else if (!this.getItem().isEmpty() && this.getItem().is(Items.NETHER_STAR) && source.is(DamageTypeTags.IS_EXPLOSION)) {
             return false;
@@ -580,6 +595,12 @@ public class ItemEntity extends Entity implements TraceableEntity {
     public void setItem(ItemStack stack) {
         this.getEntityData().set(ItemEntity.DATA_ITEM, stack);
         this.despawnRate = this.level().paperConfig().entities.spawning.altItemDespawnRate.enabled ? this.level().paperConfig().entities.spawning.altItemDespawnRate.items.getOrDefault(stack.getItem(), this.level().spigotConfig.itemDespawnRate) : this.level().spigotConfig.itemDespawnRate; // Paper - Alternative item-despawn-rate
+        // Purpur start
+        if (level().purpurConfig.itemImmuneToCactus.contains(stack.getItem())) immuneToCactus = true;
+        if (level().purpurConfig.itemImmuneToExplosion.contains(stack.getItem())) immuneToExplosion = true;
+        if (level().purpurConfig.itemImmuneToFire.contains(stack.getItem())) immuneToFire = true;
+        if (level().purpurConfig.itemImmuneToLightning.contains(stack.getItem())) immuneToLightning = true;
+        // level end
     }
 
     @Override
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
index 30d62ee4d5cd2ddacb8783b5bbbf475d592b3e02..01e4395f1669d21c30465aa1366bd2f1ae17678f 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
@@ -151,4 +151,46 @@ public class CraftItem extends CraftEntity implements Item {
     public String toString() {
         return "CraftItem";
     }
+
+    // Purpur start
+    @Override
+    public void setImmuneToCactus(boolean immuneToCactus) {
+        this.getHandle().immuneToCactus = immuneToCactus;
+    }
+
+    @Override
+    public boolean isImmuneToCactus() {
+        return this.getHandle().immuneToCactus;
+    }
+
+    @Override
+    public void setImmuneToExplosion(boolean immuneToExplosion) {
+        this.getHandle().immuneToExplosion = immuneToExplosion;
+    }
+
+    @Override
+    public boolean isImmuneToExplosion() {
+        return this.getHandle().immuneToExplosion;
+    }
+
+    @Override
+    public void setImmuneToFire(boolean immuneToFire) {
+        item.immuneToFire = immuneToFire;
+    }
+
+    @Override
+    public boolean isImmuneToFire() {
+        return this.getHandle().immuneToFire;
+    }
+
+    @Override
+    public void setImmuneToLightning(boolean immuneToLightning) {
+        this.getHandle().immuneToLightning = immuneToLightning;
+    }
+
+    @Override
+    public boolean isImmuneToLightning() {
+        return this.getHandle().immuneToLightning;
+    }
+    // Purpur end
 }
diff --git a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
index 238cec1e37fcc9ca676a680ee616b43f1312dbd0..b2bc8d014b9cfd7af72b0a04077f93741338083a 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
@@ -124,6 +124,49 @@ public class PurpurWorldConfig {
         elytraDamagePerTridentBoost = getInt("gameplay-mechanics.elytra.damage-per-boost.trident", elytraDamagePerTridentBoost);
     }
 
+    public List<Item> itemImmuneToCactus = new ArrayList<>();
+    public List<Item> itemImmuneToExplosion = new ArrayList<>();
+    public List<Item> itemImmuneToFire = new ArrayList<>();
+    public List<Item> itemImmuneToLightning = new ArrayList<>();
+    private void itemSettings() {
+        itemImmuneToCactus.clear();
+        getList("gameplay-mechanics.item.immune.cactus", new ArrayList<>()).forEach(key -> {
+            if (key.toString().equals("*")) {
+                BuiltInRegistries.ITEM.stream().filter(item -> item != Items.AIR).forEach((item) -> itemImmuneToCactus.add(item));
+                return;
+            }
+            Item item = BuiltInRegistries.ITEM.get(ResourceLocation.parse(key.toString()));
+            if (item != Items.AIR) itemImmuneToCactus.add(item);
+        });
+        itemImmuneToExplosion.clear();
+        getList("gameplay-mechanics.item.immune.explosion", new ArrayList<>()).forEach(key -> {
+            if (key.toString().equals("*")) {
+                BuiltInRegistries.ITEM.stream().filter(item -> item != Items.AIR).forEach((item) -> itemImmuneToExplosion.add(item));
+                return;
+            }
+            Item item = BuiltInRegistries.ITEM.get(ResourceLocation.parse(key.toString()));
+            if (item != Items.AIR) itemImmuneToExplosion.add(item);
+        });
+        itemImmuneToFire.clear();
+        getList("gameplay-mechanics.item.immune.fire", new ArrayList<>()).forEach(key -> {
+            if (key.toString().equals("*")) {
+                BuiltInRegistries.ITEM.stream().filter(item -> item != Items.AIR).forEach((item) -> itemImmuneToFire.add(item));
+                return;
+            }
+            Item item = BuiltInRegistries.ITEM.get(ResourceLocation.parse(key.toString()));
+            if (item != Items.AIR) itemImmuneToFire.add(item);
+        });
+        itemImmuneToLightning.clear();
+        getList("gameplay-mechanics.item.immune.lightning", new ArrayList<>()).forEach(key -> {
+            if (key.toString().equals("*")) {
+                BuiltInRegistries.ITEM.stream().filter(item -> item != Items.AIR).forEach((item) -> itemImmuneToLightning.add(item));
+                return;
+            }
+            Item item = BuiltInRegistries.ITEM.get(ResourceLocation.parse(key.toString()));
+            if (item != Items.AIR) itemImmuneToLightning.add(item);
+        });
+    }
+
     public double minecartMaxSpeed = 0.4D;
     public boolean minecartPlaceAnywhere = false;
     public boolean minecartControllable = false;