From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Thu, 6 May 2021 19:57:58 -0700
Subject: [PATCH] More Enchantment API

== AT ==
public net.minecraft.world.item.enchantment.Enchantment slots

diff --git a/src/main/java/org/bukkit/craftbukkit/enchantments/CraftEnchantment.java b/src/main/java/org/bukkit/craftbukkit/enchantments/CraftEnchantment.java
index 5b09e7e08c61b10044ac5f481bf10bb79feda8a3..06a857ae432fc81737b53a6d2b8742c1e80e5f8a 100644
--- a/src/main/java/org/bukkit/craftbukkit/enchantments/CraftEnchantment.java
+++ b/src/main/java/org/bukkit/craftbukkit/enchantments/CraftEnchantment.java
@@ -71,7 +71,7 @@ public class CraftEnchantment extends Enchantment {
 
     @Override
     public boolean isCursed() {
-        return this.target instanceof BindingCurseEnchantment || this.target instanceof VanishingCurseEnchantment;
+        return this.target.isCurse(); // Paper
     }
 
     @Override
@@ -199,6 +199,45 @@ public class CraftEnchantment extends Enchantment {
     public String translationKey() {
         return this.target.getDescriptionId();
     }
+
+    @Override
+    public boolean isTradeable() {
+        return target.isTradeable();
+    }
+
+    @Override
+    public boolean isDiscoverable() {
+        return target.isDiscoverable();
+    }
+
+    @Override
+    public io.papermc.paper.enchantments.EnchantmentRarity getRarity() {
+        return fromNMSRarity(target.getRarity());
+    }
+
+    @Override
+    public float getDamageIncrease(int level, org.bukkit.entity.EntityCategory entityCategory) {
+        return target.getDamageBonus(level, org.bukkit.craftbukkit.entity.CraftLivingEntity.fromBukkitEntityCategory(entityCategory));
+    }
+
+    @Override
+    public java.util.Set<org.bukkit.inventory.EquipmentSlot> getActiveSlots() {
+        return java.util.stream.Stream.of(target.slots).map(org.bukkit.craftbukkit.CraftEquipmentSlot::getSlot).collect(java.util.stream.Collectors.toSet());
+    }
+
+    public static io.papermc.paper.enchantments.EnchantmentRarity fromNMSRarity(net.minecraft.world.item.enchantment.Enchantment.Rarity nmsRarity) {
+        if (nmsRarity == net.minecraft.world.item.enchantment.Enchantment.Rarity.COMMON) {
+            return io.papermc.paper.enchantments.EnchantmentRarity.COMMON;
+        } else if (nmsRarity == net.minecraft.world.item.enchantment.Enchantment.Rarity.UNCOMMON) {
+            return io.papermc.paper.enchantments.EnchantmentRarity.UNCOMMON;
+        } else if (nmsRarity == net.minecraft.world.item.enchantment.Enchantment.Rarity.RARE) {
+            return io.papermc.paper.enchantments.EnchantmentRarity.RARE;
+        } else if (nmsRarity == net.minecraft.world.item.enchantment.Enchantment.Rarity.VERY_RARE) {
+            return io.papermc.paper.enchantments.EnchantmentRarity.VERY_RARE;
+        }
+
+        throw new IllegalArgumentException(String.format("Unable to convert %s to a enum value of %s.", nmsRarity, io.papermc.paper.enchantments.EnchantmentRarity.class));
+    }
     // Paper end
 
     public net.minecraft.world.item.enchantment.Enchantment getHandle() {
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
index 62700f1190bda9cb05514096e426eb3eeb87504c..3d3f7198a6134ced5c2dd25e369cb4e8d8f45fd1 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
@@ -949,5 +949,21 @@ public class CraftLivingEntity extends CraftEntity implements LivingEntity {
     public void setHurtDirection(float hurtDirection) {
         throw new UnsupportedOperationException("Cannot set the hurt direction on a non player");
     }
+
+    public static MobType fromBukkitEntityCategory(EntityCategory entityCategory) {
+        switch (entityCategory) {
+            case NONE:
+                return MobType.UNDEFINED;
+            case UNDEAD:
+                return MobType.UNDEAD;
+            case ARTHROPOD:
+                return MobType.ARTHROPOD;
+            case ILLAGER:
+                return MobType.ILLAGER;
+            case WATER:
+                return MobType.WATER;
+        }
+        throw new IllegalArgumentException(entityCategory + " is an unrecognized entity category");
+    }
     // Paper end
 }
diff --git a/src/test/java/io/papermc/paper/enchantments/EnchantmentRarityTest.java b/src/test/java/io/papermc/paper/enchantments/EnchantmentRarityTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..03a53ceb0dc3aaff7b5d10ec57f74d71be90ec3a
--- /dev/null
+++ b/src/test/java/io/papermc/paper/enchantments/EnchantmentRarityTest.java
@@ -0,0 +1,18 @@
+package io.papermc.paper.enchantments;
+
+import net.minecraft.world.item.enchantment.Enchantment.Rarity;
+import org.bukkit.craftbukkit.enchantments.CraftEnchantment;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+public class EnchantmentRarityTest {
+
+    @Test
+    public void test() {
+        for (Rarity nmsRarity : Rarity.values()) {
+            // Will throw exception if a bukkit counterpart is not found
+            CraftEnchantment.fromNMSRarity(nmsRarity);
+        }
+    }
+}
diff --git a/src/test/java/io/papermc/paper/entity/EntityCategoryTest.java b/src/test/java/io/papermc/paper/entity/EntityCategoryTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..4ee48ef89f0e31a7bda4b04453fca8177874f540
--- /dev/null
+++ b/src/test/java/io/papermc/paper/entity/EntityCategoryTest.java
@@ -0,0 +1,34 @@
+package io.papermc.paper.entity;
+
+import com.google.common.base.Joiner;
+import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
+import net.minecraft.world.entity.MobType;
+import org.bukkit.craftbukkit.entity.CraftLivingEntity;
+import org.bukkit.entity.EntityCategory;
+import org.junit.jupiter.api.Test;
+
+import java.lang.reflect.Field;
+import java.util.Map;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class EntityCategoryTest {
+
+    @Test
+    public void test() throws IllegalAccessException {
+
+        Map<MobType, String> enumMonsterTypeFieldMap = Maps.newHashMap();
+        for (Field field : MobType.class.getDeclaredFields()) {
+            if (field.getType() == MobType.class) {
+                enumMonsterTypeFieldMap.put( (MobType) field.get(null), field.getName());
+            }
+        }
+
+        for (EntityCategory entityCategory : EntityCategory.values()) {
+            enumMonsterTypeFieldMap.remove(CraftLivingEntity.fromBukkitEntityCategory(entityCategory));
+        }
+        assertTrue(enumMonsterTypeFieldMap.size() == 0, MobType.class.getName() + " instance(s): " + Joiner.on(", ").join(enumMonsterTypeFieldMap.values()) + " do not have bukkit equivalents");
+    }
+}