Kotlinify JavaScriptModuleRegistry (#51164)

Summary:
Pull Request resolved: #51164

As per title.

Changelog: [Internal]

Reviewed By: javache

Differential Revision: D74326679

fbshipit-source-id: ecd15fda9ea8686b65171c462e7e82dc9609377b

Author: fabriziocucci

packages/react-native/ReactAndroid/api/ReactAndroid.api

@@ -921,9 +921,14 @@ public abstract interface class com/facebook/react/bridge/JavaScriptModule {
 }
 
 public final class com/facebook/react/bridge/JavaScriptModuleRegistry {
+	public static final field Companion Lcom/facebook/react/bridge/JavaScriptModuleRegistry$Companion;
 	public fun <init> ()V
-	public static fun getJSModuleName (Ljava/lang/Class;)Ljava/lang/String;
-	public fun getJavaScriptModule (Lcom/facebook/react/bridge/CatalystInstance;Ljava/lang/Class;)Lcom/facebook/react/bridge/JavaScriptModule;
+	public static final fun getJSModuleName (Ljava/lang/Class;)Ljava/lang/String;
+	public final fun getJavaScriptModule (Lcom/facebook/react/bridge/CatalystInstance;Ljava/lang/Class;)Lcom/facebook/react/bridge/JavaScriptModule;
+}
+
+public final class com/facebook/react/bridge/JavaScriptModuleRegistry$Companion {
+	public final fun getJSModuleName (Ljava/lang/Class;)Ljava/lang/String;
 }
 
 public final class com/facebook/react/bridge/JsonWriterHelper {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/bridge/JavaScriptModuleRegistry.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.bridge
+
+import com.facebook.react.common.build.ReactBuildConfig
+import java.lang.reflect.InvocationHandler
+import java.lang.reflect.Method
+import java.lang.reflect.Proxy
+
+/**
+ * Class responsible for holding all the [JavaScriptModule]s. Uses Java proxy objects to dispatch
+ * method calls on JavaScriptModules to the bridge using the corresponding module and method ids so
+ * the proper function is executed in JavaScript.
+ */
+public class JavaScriptModuleRegistry {
+
+  private val moduleInstances: MutableMap<Class<out JavaScriptModule>, JavaScriptModule> = HashMap()
+
+  @Synchronized
+  public fun <T : JavaScriptModule> getJavaScriptModule(
+      @Suppress("DEPRECATION") instance: CatalystInstance,
+      moduleInterface: Class<T>
+  ): T {
+    val module = moduleInstances[moduleInterface]
+    if (module != null) {
+      @Suppress("UNCHECKED_CAST")
+      return module as T
+    }
+
+    val proxy =
+        Proxy.newProxyInstance(
+            moduleInterface.classLoader,
+            arrayOf<Class<*>>(moduleInterface),
+            JavaScriptModuleInvocationHandler(instance, moduleInterface)) as JavaScriptModule
+
+    moduleInstances[moduleInterface] = proxy
+    @Suppress("UNCHECKED_CAST")
+    return proxy as T
+  }
+
+  private class JavaScriptModuleInvocationHandler(
+      @Suppress("DEPRECATION") private val catalystInstance: CatalystInstance,
+      private val moduleInterface: Class<out JavaScriptModule>
+  ) : InvocationHandler {
+
+    private var name: String? = null
+
+    init {
+      if (ReactBuildConfig.DEBUG) {
+        val methodNames = mutableSetOf<String>()
+        for (method in moduleInterface.declaredMethods) {
+          if (!methodNames.add(method.name)) {
+            throw AssertionError(
+                "Method overloading is unsupported: ${moduleInterface.name}#${method.name}")
+          }
+        }
+      }
+    }
+
+    private fun getJSModuleName(): String {
+      // Getting the class name every call is expensive, so cache it
+      return name ?: getJSModuleName(moduleInterface).also { name = it }
+    }
+
+    public override fun invoke(proxy: Any, method: Method, args: Array<Any?>?): Any? {
+      val jsArgs = if (args != null) Arguments.fromJavaArgs(args) else WritableNativeArray()
+      catalystInstance.callFunction(getJSModuleName(), method.name, jsArgs)
+      return null
+    }
+  }
+
+  public companion object {
+    /**
+     * With proguard obfuscation turned on, proguard apparently (poorly) emulates inner classes or
+     * something because Class#getSimpleName() no longer strips the outer class name. We manually
+     * strip it here if necessary.
+     */
+    @JvmStatic
+    public fun getJSModuleName(jsModuleInterface: Class<out JavaScriptModule>): String {
+      var name = jsModuleInterface.simpleName
+      val dollarSignIndex = name.lastIndexOf('$')
+      if (dollarSignIndex != -1) {
+        name = name.substring(dollarSignIndex + 1)
+      }
+      return name
+    }
+  }
+}