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 b7fd8e70413c38923d0719aff803449e392383ac..11d7aef930ca283950f7b353b033f3ec5fe41efb 100644
--- a/src/main/java/net/minecraft/server/level/ServerEntity.java
+++ b/src/main/java/net/minecraft/server/level/ServerEntity.java
@@ -72,7 +72,7 @@ public class ServerEntity {
     @Nullable
     private List<SynchedEntityData.DataValue<?>> trackedDataValues;
     // CraftBukkit start
-    final Set<ServerPlayerConnection> trackedPlayers; // Paper - private -> package
+    public final Set<ServerPlayerConnection> trackedPlayers; // Paper - private -> package // Purpur - package -> 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 d47b3ac633e7936d30abfda6fc46c2c7412d76fe..1b7784666312d50a957d023c2bf869194ee9e593 100644
--- a/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
+++ b/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
@@ -55,6 +55,12 @@ public class ItemEntity extends Entity implements TraceableEntity {
     public boolean canMobPickup = true; // Paper
     private int despawnRate = -1; // Paper
     public net.kyori.adventure.util.TriState frictionState = net.kyori.adventure.util.TriState.NOT_SET; // Paper
+    // 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);
@@ -343,6 +349,15 @@ public class ItemEntity extends Entity implements TraceableEntity {
             return false;
         } else if (!this.getItem().getItem().canBeHurtBy(source)) {
             return false;
+        // Purpur start
+        } else if (
+                (immuneToCactus && source.is(net.minecraft.world.damagesource.DamageTypes.CACTUS)) ||
+                (immuneToFire && (source.is(DamageTypeTags.IS_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;
+        // Purpur end
         } else if (this.level.isClientSide) {
             return true;
         } else {
@@ -541,6 +556,12 @@ public class ItemEntity extends Entity implements TraceableEntity {
         this.getEntityData().set(ItemEntity.DATA_ITEM, stack);
         this.getEntityData().markDirty(ItemEntity.DATA_ITEM); // CraftBukkit - SPIGOT-4591, must mark dirty
         this.despawnRate = level.paperConfig().entities.spawning.altItemDespawnRate.enabled ? level.paperConfig().entities.spawning.altItemDespawnRate.items.getOrDefault(stack.getItem(), level.spigotConfig.itemDespawnRate) : level.spigotConfig.itemDespawnRate; // Paper
+        // 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 a925b5c490e7129b27370aa57b5fad1cf05530c6..09001578b88658c44d0661d340a0ee0f1ded6911 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
@@ -160,4 +160,46 @@ public class CraftItem extends CraftEntity implements Item {
     public EntityType getType() {
         return EntityType.DROPPED_ITEM;
     }
+
+    // Purpur start
+    @Override
+    public void setImmuneToCactus(boolean immuneToCactus) {
+        item.immuneToCactus = immuneToCactus;
+    }
+
+    @Override
+    public boolean isImmuneToCactus() {
+        return item.immuneToCactus;
+    }
+
+    @Override
+    public void setImmuneToExplosion(boolean immuneToExplosion) {
+        item.immuneToExplosion = immuneToExplosion;
+    }
+
+    @Override
+    public boolean isImmuneToExplosion() {
+        return item.immuneToExplosion;
+    }
+
+    @Override
+    public void setImmuneToFire(boolean immuneToFire) {
+        item.immuneToFire = immuneToFire;
+    }
+
+    @Override
+    public boolean isImmuneToFire() {
+        return item.immuneToFire;
+    }
+
+    @Override
+    public void setImmuneToLightning(boolean immuneToLightning) {
+        item.immuneToLightning = immuneToLightning;
+    }
+
+    @Override
+    public boolean isImmuneToLightning() {
+        return item.immuneToLightning;
+    }
+    // Purpur end
 }
diff --git a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
index 55b7f582c6bc06412900e843c3263a69e67d2af5..ead0ea1613da4a23fe20283555f3dd7e55299073 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
@@ -127,6 +127,49 @@ 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(new ResourceLocation(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(new ResourceLocation(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(new ResourceLocation(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(new ResourceLocation(key.toString()));
+            if (item != Items.AIR) itemImmuneToLightning.add(item);
+        });
+    }
+
     public double minecartMaxSpeed = 0.4D;
     public boolean minecartPlaceAnywhere = false;
     public boolean minecartControllable = false;