From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Wed, 20 Dec 2023 02:03:10 -0800
Subject: [PATCH] Improve Registry

Adds Registry#getKey(Object) which should be the
primary way people get the key for an object. Registry
items need to exist without having a key and so
getKey() methods on Keyed objects that have a registry
are marked as Deprecated or Obsolete.

diff --git a/src/main/java/org/bukkit/MusicInstrument.java b/src/main/java/org/bukkit/MusicInstrument.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/MusicInstrument.java
+++ b/src/main/java/org/bukkit/MusicInstrument.java
@@ -0,0 +0,0 @@ public abstract class MusicInstrument implements Keyed, net.kyori.adventure.tran
         return instrument;
     }
 
+    // Paper start - deprecate getKey
+    /**
+     * @deprecated use {@link Registry#getKey(Keyed)} and {@link Registry#INSTRUMENT}. MusicInstruments
+     * can exist without a key.
+     */
+    @Deprecated
+    @Override
+    public abstract @NotNull NamespacedKey getKey();
+    // Paper end - deprecate getKey
+
     // Paper start - translation key
     @Override
     public @NotNull String translationKey() {
diff --git a/src/main/java/org/bukkit/Registry.java b/src/main/java/org/bukkit/Registry.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/Registry.java
+++ b/src/main/java/org/bukkit/Registry.java
@@ -0,0 +0,0 @@ public interface Registry<T extends Keyed> extends Iterable<T> {
     @Nullable
     T get(@NotNull NamespacedKey key);
 
+    // Paper start - improve Registry
+    /**
+     * Gets the key for this object or throws if it doesn't exist.
+     * <p>
+     * Some types can exist without being in a registry
+     * and such will have no key associated with them. This
+     * method throw an exception if it isn't in this registry.
+     *
+     * @param value the value to get the key of in this registry
+     * @return the key for the value
+     * @throws java.util.NoSuchElementException if the value doesn't exist in this registry
+     * @see #getKey(Keyed)
+     */
+    default @NotNull NamespacedKey getKeyOrThrow(final @NotNull T value) {
+        Preconditions.checkArgument(value != null, "value cannot be null");
+        final NamespacedKey key = this.getKey(value);
+        if (key == null) {
+            throw new java.util.NoSuchElementException(value + " has no key in " + this);
+        }
+        return key;
+    }
+
+    /**
+     * Get the key for this object.
+     * <p>
+     * Some types can exist without being in a registry
+     * and such will have no key associated with them. This
+     * method will return null.
+     *
+     * @param value the value to get the key of in this registry
+     * @return the key for the value or null if not in the registry
+     * @see #getKeyOrThrow(Keyed)
+     */
+    default @Nullable NamespacedKey getKey(final @NotNull T value) {
+        Preconditions.checkArgument(value != null, "value cannot be null");
+        //noinspection ConstantValue (it might not be in the future...)
+        if (value instanceof Keyed) {
+            return value.getKey();
+        }
+        return null;
+    }
+    // Paper end - improve Registry
+
     /**
      * Returns a new stream, which contains all registry items, which are registered to the registry.
      *
@@ -0,0 +0,0 @@ public interface Registry<T extends Keyed> extends Iterable<T> {
         public Class<T> getType() {
             return this.type;
         }
+
+        // Paper start - improve Registry
+        @Override
+        public @NotNull NamespacedKey getKey(final @NotNull T value) {
+            return value.getKey();
+        }
+        // Paper end - improve Registry
     }
 }
diff --git a/src/main/java/org/bukkit/block/banner/PatternType.java b/src/main/java/org/bukkit/block/banner/PatternType.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/block/banner/PatternType.java
+++ b/src/main/java/org/bukkit/block/banner/PatternType.java
@@ -0,0 +0,0 @@ public enum PatternType implements Keyed {
         this.key = NamespacedKey.minecraft(key);
     }
 
+    // Paper start - deprecate getKey
+    /**
+     * @deprecated use {@link Registry#getKey(Keyed)} and {@link Registry#BANNER_PATTERN}. PatternTypes
+     * can exist without a key.
+     */
+    @Deprecated
+    // Paper end - deprecate getKey
     @Override
     @NotNull
     public NamespacedKey getKey() {
diff --git a/src/main/java/org/bukkit/generator/structure/Structure.java b/src/main/java/org/bukkit/generator/structure/Structure.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/generator/structure/Structure.java
+++ b/src/main/java/org/bukkit/generator/structure/Structure.java
@@ -0,0 +0,0 @@ public abstract class Structure implements Keyed {
      */
     @NotNull
     public abstract StructureType getStructureType();
+    // Paper start - deprecate getKey
+    /**
+     * @deprecated use {@link Registry#getKey(Keyed)} and {@link Registry#STRUCTURE}. Structures
+     * can exist without a key.
+     */
+    @Override
+    @Deprecated
+    public abstract @NotNull NamespacedKey getKey();
+    // Paper end - deprecate getKey
 }
diff --git a/src/main/java/org/bukkit/inventory/meta/trim/TrimMaterial.java b/src/main/java/org/bukkit/inventory/meta/trim/TrimMaterial.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/inventory/meta/trim/TrimMaterial.java
+++ b/src/main/java/org/bukkit/inventory/meta/trim/TrimMaterial.java
@@ -0,0 +0,0 @@ public interface TrimMaterial extends Keyed, Translatable {
     @Deprecated(forRemoval = true)
     @org.jetbrains.annotations.NotNull String getTranslationKey();
     // Paper end - adventure
+
+    // Paper start - Registry#getKey
+    /**
+     * @deprecated use {@link Registry#getKey(Keyed)} and {@link Registry#TRIM_MATERIAL}. TrimMaterials
+     * can exist without a key.
+     */
+    @Deprecated(forRemoval = true, since = "1.20.4")
+    @Override
+    org.bukkit.@org.jetbrains.annotations.NotNull NamespacedKey getKey();
+    // Paper end - Registry#getKey
 }
diff --git a/src/main/java/org/bukkit/inventory/meta/trim/TrimPattern.java b/src/main/java/org/bukkit/inventory/meta/trim/TrimPattern.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/inventory/meta/trim/TrimPattern.java
+++ b/src/main/java/org/bukkit/inventory/meta/trim/TrimPattern.java
@@ -0,0 +0,0 @@ public interface TrimPattern extends Keyed, Translatable {
     @Deprecated(forRemoval = true)
     @org.jetbrains.annotations.NotNull String getTranslationKey();
     // Paper end - adventure
+
+    // Paper start - Registry#getKey
+    /**
+     * @deprecated use {@link Registry#getKey(Keyed)} and {@link Registry#TRIM_PATTERN}. TrimPatterns
+     * can exist without a key.
+     */
+    @Deprecated(forRemoval = true, since = "1.20.4")
+    @Override
+    org.bukkit.@org.jetbrains.annotations.NotNull NamespacedKey getKey();
+    // Paper end - Registry#getKey
 }
