[core] Introduce arity for structured sub entries

tweed5/core/src/main/java/de/siphalor/tweed5/core/api/Arity.java

@@ -0,0 +1,17 @@
+package de.siphalor.tweed5.core.api;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+@Getter
+public enum Arity {
+	SINGLE(1, 1),
+	OPTIONAL(0, 1),
+	MULTIPLE(1, Integer.MAX_VALUE),
+	ANY(0, Integer.MAX_VALUE),
+	;
+
+	private final int min;
+	private final int max;
+}

tweed5/core/src/main/java/de/siphalor/tweed5/core/api/entry/CollectionConfigEntry.java

@@ -1,5 +1,6 @@
 package de.siphalor.tweed5.core.api.entry;
 
+import de.siphalor.tweed5.core.api.Arity;
 import org.jspecify.annotations.Nullable;
 
 import java.util.Collection;
@@ -14,6 +15,19 @@ public interface CollectionConfigEntry<E, T extends Collection<E>> extends Struc
 		return this;
 	}
 
+	@Override
+	default void visitInOrder(ConfigEntryVisitor visitor) {
+		if (visitor.enterStructuredEntry(this)) {
+			subEntries().forEach((key, entry) -> {
+				if (visitor.enterStructuredSubEntry(key, Arity.ANY)) {
+					entry.visitInOrder(visitor);
+					visitor.leaveStructuredSubEntry(key, Arity.ANY);
+				}
+			});
+			visitor.leaveStructuredEntry(this);
+		}
+	}
+
 	@Override
 	default void visitInOrder(ConfigEntryValueVisitor visitor, @Nullable T value) {
 		if (value == null) {

tweed5/core/src/main/java/de/siphalor/tweed5/core/api/entry/CompoundConfigEntry.java

@@ -1,5 +1,7 @@
 package de.siphalor.tweed5.core.api.entry;
 
+import de.siphalor.tweed5.core.api.Arity;
+
 import java.util.function.Consumer;
 
 public interface CompoundConfigEntry<T> extends StructuredConfigEntry<T> {
@@ -13,4 +15,17 @@ public interface CompoundConfigEntry<T> extends StructuredConfigEntry<T> {
 	<V> V get(T compoundValue, String key);
 
 	T instantiateCompoundValue();
+
+	@Override
+	default void visitInOrder(ConfigEntryVisitor visitor) {
+		if (visitor.enterStructuredEntry(this)) {
+			subEntries().forEach((key, entry) -> {
+				if (visitor.enterStructuredSubEntry(key, Arity.SINGLE)) {
+					entry.visitInOrder(visitor);
+					visitor.leaveStructuredSubEntry(key, Arity.SINGLE);
+				}
+			});
+			visitor.leaveStructuredEntry(this);
+		}
+	}
 }

tweed5/core/src/main/java/de/siphalor/tweed5/core/api/entry/ConfigEntryVisitor.java

@@ -1,5 +1,7 @@
 package de.siphalor.tweed5.core.api.entry;
 
+import de.siphalor.tweed5.core.api.Arity;
+
 public interface ConfigEntryVisitor {
 	void visitEntry(ConfigEntry<?> entry);
 
@@ -8,11 +10,11 @@ public interface ConfigEntryVisitor {
 		return true;
 	}
 
-	default boolean enterStructuredSubEntry(String key) {
+	default boolean enterStructuredSubEntry(String key, Arity arity) {
 		return true;
 	}
 
-	default void leaveStructuredSubEntry(String key) {
+	default void leaveStructuredSubEntry(String key, Arity arity) {
 	}
 
 	default void leaveStructuredEntry(ConfigEntry<?> entry) {

tweed5/core/src/main/java/de/siphalor/tweed5/core/api/entry/NullableConfigEntry.java

@@ -1,5 +1,6 @@
 package de.siphalor.tweed5.core.api.entry;
 
+import de.siphalor.tweed5.core.api.Arity;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.function.Consumer;
@@ -14,4 +15,17 @@ public interface NullableConfigEntry<T extends @Nullable Object> extends Structu
 	}
 
 	ConfigEntry<T> nonNullEntry();
+
+	@Override
+	default void visitInOrder(ConfigEntryVisitor visitor) {
+		if (visitor.enterStructuredEntry(this)) {
+			subEntries().forEach((key, entry) -> {
+				if (visitor.enterStructuredSubEntry(key, Arity.OPTIONAL)) {
+					entry.visitInOrder(visitor);
+					visitor.leaveStructuredSubEntry(key, Arity.OPTIONAL);
+				}
+			});
+			visitor.leaveStructuredEntry(this);
+		}
+	}
 }

tweed5/core/src/main/java/de/siphalor/tweed5/core/api/entry/StructuredConfigEntry.java

@@ -10,18 +10,5 @@ public interface StructuredConfigEntry<T> extends ConfigEntry<T> {
 		return this;
 	}
 
-	@Override
-	default void visitInOrder(ConfigEntryVisitor visitor) {
-		if (visitor.enterStructuredEntry(this)) {
-			subEntries().forEach((key, entry) -> {
-				if (visitor.enterStructuredSubEntry(key)) {
-					entry.visitInOrder(visitor);
-					visitor.leaveStructuredSubEntry(key);
-				}
-			});
-			visitor.leaveStructuredEntry(this);
-		}
-	}
-
 	Map<String, ConfigEntry<?>> subEntries();
 }

tweed5/default-extensions/src/main/java/de/siphalor/tweed5/defaultextensions/pather/api/PathTrackingConfigEntryVisitor.java

@@ -1,5 +1,6 @@
 package de.siphalor.tweed5.defaultextensions.pather.api;
 
+import de.siphalor.tweed5.core.api.Arity;
 import de.siphalor.tweed5.core.api.entry.ConfigEntry;
 import de.siphalor.tweed5.core.api.entry.ConfigEntryVisitor;
 import lombok.RequiredArgsConstructor;
@@ -20,8 +21,8 @@ public class PathTrackingConfigEntryVisitor implements ConfigEntryVisitor {
 	}
 
 	@Override
-	public boolean enterStructuredSubEntry(String key) {
+	public boolean enterStructuredSubEntry(String key, Arity arity) {
-		boolean enter = delegate.enterStructuredSubEntry(key);
+		boolean enter = delegate.enterStructuredSubEntry(key, arity);
 		if (enter) {
 			pathTracking.pushPathPart(key);
 		}
@@ -29,8 +30,8 @@ public class PathTrackingConfigEntryVisitor implements ConfigEntryVisitor {
 	}
 
 	@Override
-	public void leaveStructuredSubEntry(String key) {
+	public void leaveStructuredSubEntry(String key, Arity arity) {
-		delegate.leaveStructuredSubEntry(key);
+		delegate.leaveStructuredSubEntry(key, arity);
 		pathTracking.popPathPart();
 	}