From 093a73d04639fea8dac3e925d759d362ffff517a Mon Sep 17 00:00:00 2001
From: JesseBrault0709 <62299747+JesseBrault0709@users.noreply.github.com>
Date: Fri, 3 May 2024 12:01:45 +0200
Subject: [PATCH] Initial commit. Woot!

---
 build.gradle                                  |  8 +++
 .../AbstractExtensionContainer.java           | 68 +++++++++++++++++++
 .../groowt/util/extensible/Extensible.java    | 11 +++
 .../util/extensible/ExtensionAware.java       | 12 ++++
 .../util/extensible/ExtensionContainer.java   |  5 ++
 5 files changed, 104 insertions(+)
 create mode 100644 build.gradle
 create mode 100644 src/main/java/groowt/util/extensible/AbstractExtensionContainer.java
 create mode 100644 src/main/java/groowt/util/extensible/Extensible.java
 create mode 100644 src/main/java/groowt/util/extensible/ExtensionAware.java
 create mode 100644 src/main/java/groowt/util/extensible/ExtensionContainer.java

diff --git a/build.gradle b/build.gradle
new file mode 100644
index 0000000..d6d4388
--- /dev/null
+++ b/build.gradle
@@ -0,0 +1,8 @@
+plugins {
+    id 'GroowtConventions'
+    id 'java-library'
+}
+
+dependencies {
+    compileOnlyApi libs.jetbrains.anotations
+}
diff --git a/src/main/java/groowt/util/extensible/AbstractExtensionContainer.java b/src/main/java/groowt/util/extensible/AbstractExtensionContainer.java
new file mode 100644
index 0000000..14ed5a6
--- /dev/null
+++ b/src/main/java/groowt/util/extensible/AbstractExtensionContainer.java
@@ -0,0 +1,68 @@
+package groowt.util.extensible;
+
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.function.Consumer;
+
+public abstract class AbstractExtensionContainer<E, F> implements ExtensionContainer<E, F> {
+
+    private final F extensionFactory;
+    private final Collection<E> extensions = new ArrayList<>();
+
+    public AbstractExtensionContainer(F extensionFactory) {
+        this.extensionFactory = extensionFactory;
+    }
+
+    /**
+     * @return A <strong>copy</strong> of the registered extensions.
+     */
+    protected Collection<E> getRegisteredExtensions() {
+        return new ArrayList<>(this.extensions);
+    }
+
+    protected void registerExtension(E extension) {
+        this.extensions.add(extension);
+    }
+
+    @Override
+    public <T extends E> @Nullable T findExtension(Class<T> extensionClass) {
+        return this.extensions.stream()
+                .filter(extensionClass::isInstance)
+                .findFirst()
+                .map(extensionClass::cast)
+                .orElse(null);
+    }
+
+    /**
+     * @implNote While this {@link AbstractExtensionContainer} calls
+     * {@link #getExtension}, which will throw if there is no registered
+     * extension, this method may be overridden to not use {@link #getExtension}
+     * and instead implement custom handling logic to avoid throwing, etc.
+     */
+    @Override
+    public <T extends E> void configureExtension(Class<T> extensionClass, Consumer<? super T> configure) {
+        configure.accept(this.getExtension(extensionClass));
+    }
+
+    @Override
+    public <T extends E> T getExtension(Class<T> extensionClass) {
+        return this.extensions.stream()
+                .filter(extensionClass::isInstance)
+                .findFirst()
+                .map(extensionClass::cast)
+                .orElseThrow(() -> new IllegalArgumentException("There is no registered extension for " + extensionClass.getName()));
+    }
+
+    @Override
+    public boolean hasExtension(Class<? extends E> extensionClass) {
+        return this.extensions.stream().anyMatch(extensionClass::isInstance);
+    }
+
+    @Override
+    public F getExtensionFactory() {
+        return this.extensionFactory;
+    }
+
+}
diff --git a/src/main/java/groowt/util/extensible/Extensible.java b/src/main/java/groowt/util/extensible/Extensible.java
new file mode 100644
index 0000000..53eea32
--- /dev/null
+++ b/src/main/java/groowt/util/extensible/Extensible.java
@@ -0,0 +1,11 @@
+package groowt.util.extensible;
+
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Consumer;
+
+// TODO: groovy methods to handle getting extensions via property accessors
+public interface Extensible<E, F, C extends ExtensionContainer<E, F>> extends ExtensionAware<E> {
+    <T extends E> T createExtension(Class<T> extensionClass, Object... constructorArgs);
+    C getExtensionContainer();
+}
diff --git a/src/main/java/groowt/util/extensible/ExtensionAware.java b/src/main/java/groowt/util/extensible/ExtensionAware.java
new file mode 100644
index 0000000..3a41106
--- /dev/null
+++ b/src/main/java/groowt/util/extensible/ExtensionAware.java
@@ -0,0 +1,12 @@
+package groowt.util.extensible;
+
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Consumer;
+
+public interface ExtensionAware<E> {
+    @Nullable <T extends E> T findExtension(Class<T> extensionClass);
+    <T extends E> void configureExtension(Class<T> extensionClass, Consumer<? super T> configure);
+    <T extends E> T getExtension(Class<T> extensionClass);
+    boolean hasExtension(Class<? extends E> extensionClass);
+}
diff --git a/src/main/java/groowt/util/extensible/ExtensionContainer.java b/src/main/java/groowt/util/extensible/ExtensionContainer.java
new file mode 100644
index 0000000..1d85527
--- /dev/null
+++ b/src/main/java/groowt/util/extensible/ExtensionContainer.java
@@ -0,0 +1,5 @@
+package groowt.util.extensible;
+
+public interface ExtensionContainer<E, F> extends ExtensionAware<E> {
+    F getExtensionFactory();
+}