fix(android): search for node_modules in a wider scope (#488)

android/build.gradle

@@ -1,3 +1,5 @@
+import java.nio.file.Paths
+
 buildscript {
   // The Android Gradle plugin is only required when opening the android folder stand-alone.
   // This avoids unnecessary downloads and potential conflicts when the library is included as a
@@ -41,18 +43,47 @@ def getExtOrIntegerDefault(name) {
 
 apply plugin: 'com.android.library'
 
+/**
+ * Original code: https://github.com/facebook/react-native/blob/main/packages/react-native/ReactAndroid/build.gradle#L382
+ *
+ * Finds the path of the installed npm package with the given name using Node's
+ * module resolution algorithm, which searches "node_modules" directories up to
+ * the file system root. This handles various cases, including:
+ *
+ *   - Working in the open-source RN repo:
+ *       Gradle: /path/to/react-native/ReactAndroid
+ *       Node module: /path/to/react-native/node_modules/[package]
+ *
+ *   - Installing RN as a dependency of an app and searching for hoisted
+ *     dependencies:
+ *       Gradle: /path/to/app/node_modules/react-native/ReactAndroid
+ *       Node module: /path/to/app/node_modules/[package]
+ *
+ *   - Working in a larger repo (e.g., Facebook) that contains RN:
+ *       Gradle: /path/to/repo/path/to/react-native/ReactAndroid
+ *       Node module: /path/to/repo/node_modules/[package]
+ *
+ * The search begins at the given base directory (a File object). The returned
+ * path is a string.
+ */
+def findNodeModulePath(baseDir, packageName) {
+    def basePath = baseDir.toPath().normalize()
+    // Node's module resolution algorithm searches up to the root directory,
+    // after which the base path will be null
+    while (basePath) {
+        def candidatePath = Paths.get(basePath.toString(), "node_modules", packageName)
+        if (candidatePath.toFile().exists()) {
+            return candidatePath.toString()
+        }
+        basePath = basePath.getParent()
+    }
+    return null
+}
 
 def resolveReactNativeDirectory() {
-    // monorepo workaround
-    // react-native can be hoisted or in project's own node_modules
-    def reactNativeFromProjectNodeModules = file("${rootProject.projectDir}/../node_modules/react-native")
-    if (reactNativeFromProjectNodeModules.exists()) {
-        return reactNativeFromProjectNodeModules
-    }
-
-    def reactNativeFromNodeModulesWithLibrary = file("${projectDir}/../../react-native")
-    if (reactNativeFromNodeModulesWithLibrary.exists()) {
-        return reactNativeFromNodeModulesWithLibrary
+    def reactNative = file("${findNodeModulePath(rootProject.projectDir, "react-native")}")
+    if (reactNative.exists()) {
+        return reactNative
     }
 
     throw new Exception(