Add global change hook

common/src/main/java/dev/xpple/betterconfig/api/Config.java

@@ -62,7 +62,7 @@
  *     @Config(onChange = "exampleOnChange")
  *     public static String exampleString = "defaultString";
  *     public static void exampleOnChange(String oldValue, String newValue) {
- *         System.out.println("Old: " + oldValue + ", new: " + newValue);
+ *         LOGGER.info("exampleOnChange was updated | old: {}, new: {}", oldValue, newValue);
  *     }
  *     }
  *     </pre>

common/src/main/java/dev/xpple/betterconfig/api/GlobalChangeEvent.java

@@ -0,0 +1,15 @@
+package dev.xpple.betterconfig.api;
+
+import org.jetbrains.annotations.ApiStatus;
+
+/**
+ * An event object that is created whenever any config value is updated.
+ * @param config the name of the config that was changed
+ * @param oldValue the config's old value
+ * @param newValue the config's new value
+ */
+public record GlobalChangeEvent(String config, Object oldValue, Object newValue) {
+    @ApiStatus.Internal
+    public GlobalChangeEvent {
+    }
+}

common/src/main/java/dev/xpple/betterconfig/api/ModConfigBuilder.java

@@ -9,6 +9,7 @@
 
 import java.util.HashMap;
 import java.util.Map;
+import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Supplier;
 
@@ -21,6 +22,8 @@ public final class ModConfigBuilder<S, C> {
     private final GsonBuilder builder = new GsonBuilder().serializeNulls().enableComplexMapKeySerialization();
     private final Map<Class<?>, Function<C, ? extends ArgumentType<?>>> arguments = new HashMap<>();
 
+    private Consumer<GlobalChangeEvent> globalChangeHook = event -> {};
+
     public ModConfigBuilder(String modId, Class<?> configsClass) {
         this.modId = modId;
         this.configsClass = configsClass;
@@ -98,12 +101,23 @@ public <T> ModConfigBuilder<S, C> registerTypeHierarchy(Class<T> type, TypeAdapt
         return this;
     }
 
+    /**
+     * Register a callback that will be called whenever any config value is updated. See
+     * {@link GlobalChangeEvent} for the event context that is available in the callback.
+     * @param hook the callback
+     * @return the current builder instance
+     */
+    public ModConfigBuilder<S, C> registerGlobalChangeHook(Consumer<GlobalChangeEvent> hook) {
+        this.globalChangeHook = hook;
+        return this;
+    }
+
     /**
      * Finalise the registration process.
      * @throws IllegalArgumentException when a configuration already exists for this mod
      */
     public void build() {
-        ModConfigImpl<?, ?> modConfig = new ModConfigImpl<>(this.modId, this.configsClass, this.builder.create(), this.arguments);
+        ModConfigImpl<?, ?> modConfig = new ModConfigImpl<>(this.modId, this.configsClass, this.builder.create(), this.arguments, this.globalChangeHook);
         if (BetterConfigImpl.getModConfigs().putIfAbsent(this.modId, modConfig) == null) {
             BetterConfigInternals.init(modConfig);
             return;

common/src/main/java/dev/xpple/betterconfig/impl/BetterConfigInternals.java

@@ -5,6 +5,7 @@
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import dev.xpple.betterconfig.BetterConfigCommon;
 import dev.xpple.betterconfig.api.Config;
+import dev.xpple.betterconfig.api.GlobalChangeEvent;
 import dev.xpple.betterconfig.util.CheckedRunnable;
 
 import java.io.BufferedReader;
@@ -403,5 +404,6 @@ static void onChange(ModConfigImpl<?, ?> modConfig, Field field, CheckedRunnable
         updater.run();
         Object newValue = modConfig.deepCopy(field.get(null), field.getGenericType());
         onChange.accept(oldValue, newValue);
+        modConfig.getGlobalChangeHook().accept(new GlobalChangeEvent(field.getName(), oldValue, newValue));
     }
 }

common/src/main/java/dev/xpple/betterconfig/impl/ModConfigImpl.java

@@ -12,6 +12,7 @@
 import com.mojang.brigadier.arguments.StringArgumentType;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import dev.xpple.betterconfig.BetterConfigCommon;
+import dev.xpple.betterconfig.api.GlobalChangeEvent;
 import dev.xpple.betterconfig.api.ModConfig;
 import dev.xpple.betterconfig.api.Config;
 import dev.xpple.betterconfig.util.CheckedBiConsumer;
@@ -27,6 +28,7 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.function.BiConsumer;
+import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
 
@@ -64,12 +66,15 @@ public class ModConfigImpl<S, C> implements ModConfig {
     private final Gson inlineGson;
     private final Map<Class<?>, Function<C, ? extends ArgumentType<?>>> arguments;
 
-    public ModConfigImpl(String modId, Class<?> configsClass, Gson gson, Map<Class<?>, Function<C, ? extends ArgumentType<?>>> arguments) {
+    private final Consumer<GlobalChangeEvent> globalChangeHook;
+
+    public ModConfigImpl(String modId, Class<?> configsClass, Gson gson, Map<Class<?>, Function<C, ? extends ArgumentType<?>>> arguments, Consumer<GlobalChangeEvent> globalChangeHook) {
         this.modId = modId;
         this.configsClass = configsClass;
         this.gson = gson.newBuilder().setPrettyPrinting().create();
         this.inlineGson = gson;
         this.arguments = arguments;
+        this.globalChangeHook = globalChangeHook;
     }
 
     @Override
@@ -126,6 +131,10 @@ Map<String, BiConsumer<Object, Object>> getOnChangeCallbacks() {
         return this.onChangeCallbacks;
     }
 
+    Consumer<GlobalChangeEvent> getGlobalChangeHook() {
+        return this.globalChangeHook;
+    }
+
     @SuppressWarnings("unchecked")
     public Function<C, ? extends ArgumentType<?>> getArgument(Class<?> type) {
         return this.arguments.getOrDefault(type, (Function<C, ? extends ArgumentType<?>>) defaultArguments.get(type));

fabric/src/testmod/java/dev/xpple/betterconfig/Configs.java

@@ -90,6 +90,6 @@ private static void privateSetter(String string) {
     @Config(onChange = "onChange")
     public static List<String> exampleOnChange = new ArrayList<>(List.of("xpple, earthcomputer"));
     private static void onChange(List<String> oldValue, List<String> newValue) {
-        System.out.println("Old: " + oldValue + ", new: " + newValue);
+        BetterConfigCommon.LOGGER.info("exampleOnChange was updated | old: {}, new: {}", oldValue, newValue);
     }
 }

fabric/src/testmod/java/dev/xpple/betterconfig/TestMod.java

@@ -20,6 +20,7 @@ public void onInitializeServer() {
             .registerTypeHierarchy(Block.class, new BlockAdapter(), BlockWrappedArgumentType::block)
             .registerTypeHierarchy(BlockInput.class, new BlockStateAdapter(), BlockStateArgument::block)
             .registerTypeHierarchy((Class<StructureType<?>>) (Class) StructureType.class, new StructureAdapter(), StructureArgumentType::structure)
+            .registerGlobalChangeHook(event -> BetterConfigCommon.LOGGER.info("{} was updated | old: {}, new: {}", event.config(), event.oldValue(), event.newValue()))
             .build();
     }
 }

fabric/src/testmod/java/dev/xpple/betterconfig/TestModClient.java

@@ -16,6 +16,7 @@ public void onInitializeClient() {
             .registerTypeHierarchy(Block.class, new BlockAdapter(), BlockArgumentType::block)
             .registerTypeHierarchy(BlockInput.class, new BlockStateAdapter(), BlockStateArgument::block)
             .registerTypeHierarchy((Class<StructureType<?>>) (Class) StructureType.class, new StructureAdapter(), StructureArgumentType::structure)
+            .registerGlobalChangeHook(event -> BetterConfigCommon.LOGGER.info("{} was updated | old: {}, new: {}", event.config(), event.oldValue(), event.newValue()))
             .build();
     }
 }

paper/src/testplugin/java/dev/xpple/betterconfig/Configs.java

@@ -87,6 +87,6 @@ private static void privateSetter(String string) {
     @Config(onChange = "onChange")
     public static List<String> exampleOnChange = new ArrayList<>(List.of("xpple, earthcomputer"));
     private static void onChange(List<String> oldValue, List<String> newValue) {
-        System.out.println("Old: " + oldValue + ", new: " + newValue);
+        BetterConfigCommon.LOGGER.info("exampleOnChange was updated | old: {}, new: {}", oldValue, newValue);
     }
 }

paper/src/testplugin/java/dev/xpple/betterconfig/TestPlugin.java

@@ -17,6 +17,7 @@ public void onEnable() {
             .registerType(Material.class, new MaterialAdapter(), BlockMaterialArgumentType::block)
             .registerTypeHierarchy(BlockState.class, new BlockStateAdapter(), ArgumentTypes::blockState)
             .registerTypeHierarchy(Structure.class, new StructureAdapter(), StructureArgumentType::structure)
+            .registerGlobalChangeHook(event -> BetterConfigCommon.LOGGER.info("{} was updated | old: {}, new: {}", event.config(), event.oldValue(), event.newValue()))
             .build();
     }
 }