[internals] Start refactoring some of the internals to simplify, tidy up and also reduce flow type pollution

lib/utils/ModuleBase.js

@@ -1,45 +1,12 @@
 /**
  * @flow
  */
-import { NativeModules } from 'react-native';
-
-import Log from './log';
-import INTERNALS from './internals';
-import FirebaseCore from '../modules/core/firebase';
-import { nativeWithApp } from '../utils';
+import { initialiseNativeModuleEventEmitter } from './events';
+import { getNativeModule, initialiseNativeModule } from './native';
 
 import type FirebaseApp from '../modules/core/firebase-app';
 import type { FirebaseModuleName } from '../types';
 
-const logs = {};
-
-// Firebase Native SDKs that support multiple app instances
-const MULTI_APP_MODULES = [
-  'auth',
-  'database',
-  'firestore',
-  'storage',
-];
-
-const NATIVE_MODULE_EVENTS = {
-  Storage: [
-    'storage_event',
-    'storage_error',
-  ],
-  Auth: [
-    'auth_state_changed',
-    'phone_auth_state_changed',
-  ],
-  Database: [
-    'database_transaction_event',
-    // 'database_server_offset', // TODO
-  ],
-  Firestore: [
-    'firestore_collection_sync_event',
-    'firestore_document_sync_event',
-  ],
-};
-
 const DEFAULTS = {
   Database: {
     persistence: false,
@@ -53,7 +20,6 @@ export default class ModuleBase {
   _appName: string;
   _namespace: string;
   _firebaseApp: FirebaseApp;
-  _eventEmitter: Object;
   static _NAMESPACE: FirebaseModuleName;
   static _NATIVE_MODULE: string;
 
@@ -71,53 +37,15 @@ export default class ModuleBase {
     this._options = Object.assign({}, DEFAULTS[this._module] || {}, options);
 
     // check if native module exists as all native
-    // modules are now optionally part of build
-    const nativeModule = NativeModules[this.constructor._NATIVE_MODULE];
-
-    if (!nativeModule && !this.constructor._NATIVE_DISABLED) {
-      throw new Error(INTERNALS.STRINGS.ERROR_MISSING_MODULE(this.constructor._NAMESPACE, this.constructor._NATIVE_MODULE));
-    }
-
-    // used by the modules that extend ModuleBase
-    // to access their native module counterpart
-    if (!MULTI_APP_MODULES.includes(this._module.toLowerCase())) {
-      this._native = nativeModule;
-    } else {
-      this._native = nativeWithApp(this._appName, nativeModule);
-    }
+    initialiseNativeModule(this);
+    // TODO: Get rid of
+    this._native = getNativeModule(this);
 
     if (withEventEmitter) {
-      this._setupEventEmitter(nativeModule, this._module);
+      initialiseNativeModuleEventEmitter(this);
     }
   }
 
-  /**
-   *
-   * @param nativeModule
-   * @param moduleName
-   * @private
-   */
-  _setupEventEmitter(nativeModule: Object, moduleName: string) {
-    this._eventEmitter = FirebaseCore._getOrSetNativeEmitter(`${this._appName}-${this._module}`, nativeModule);
-    const events = NATIVE_MODULE_EVENTS[moduleName];
-
-    if (events && events.length) {
-      for (let i = 0, len = events.length; i < len; i++) {
-        FirebaseCore._subscribeForDistribution(events[i], this._eventEmitter);
-      }
-    }
-  }
-
-  /**
-   *
-   * @param eventName
-   * @return {string}
-   * @private
-   */
-  _getAppEventName(eventName: string) {
-    return `${this._appName}-${eventName}`;
-  }
-
   /**
    * Returns the FirebaseApp instance for current module
    * @return {*}
@@ -125,50 +53,4 @@ export default class ModuleBase {
   get app(): FirebaseApp {
     return this._firebaseApp;
   }
-
-  get log(): Log {
-    if (logs[this._namespace]) return logs[this._namespace];
-    return logs[this._namespace] = Log.createLogger(`🔥 ${this._namespace.toUpperCase()}`);
-  }
-
-  /*
-   * Proxy functions to shared event emitter instance
-   * https://github.com/facebook/react-native/blob/master/Libraries/EventEmitter/EventEmitter.js
-   */
-  get sharedEventEmitter(): Object {
-    return INTERNALS.SharedEventEmitter;
-  }
-
-  get addListener(): Function {
-    return INTERNALS.SharedEventEmitter.addListener.bind(INTERNALS.SharedEventEmitter);
-  }
-
-  get once(): Function {
-    return INTERNALS.SharedEventEmitter.once.bind(INTERNALS.SharedEventEmitter);
-  }
-
-  get on(): Function {
-    return INTERNALS.SharedEventEmitter.addListener.bind(INTERNALS.SharedEventEmitter);
-  }
-
-  get emit(): Function {
-    return INTERNALS.SharedEventEmitter.emit.bind(INTERNALS.SharedEventEmitter);
-  }
-
-  get listeners(): Function {
-    return INTERNALS.SharedEventEmitter.listeners.bind(INTERNALS.SharedEventEmitter);
-  }
-
-  hasListeners(eventType: string): Boolean {
-    const subscriptions = INTERNALS.SharedEventEmitter._subscriber.getSubscriptionsForType(eventType);
-    return subscriptions && subscriptions.length;
-  }
-
-  get removeListener(): Function {
-    return INTERNALS.SharedEventEmitter.removeListener.bind(INTERNALS.SharedEventEmitter);
-  }
-
-  get removeAllListeners(): Function {
-    return INTERNALS.SharedEventEmitter.removeAllListeners.bind(INTERNALS.SharedEventEmitter);
-  }
 }