[admob][android] Export interstitial JS module

lib/modules/admob/AdRequest.js

@@ -0,0 +1,22 @@
+export default class AdRequest {
+
+  constructor() {
+    this._props = {
+      keywords: [],
+    };
+  }
+
+  build() {
+    return this._props;
+  }
+
+  addTestDevice() {
+    this._props.testDevice = true;
+    return this;
+  }
+
+  addKeyword(word: string) {
+    this._props.keywords.push(word);
+    return this;
+  }
+}

lib/modules/admob/Interstitial.js

@@ -0,0 +1,29 @@
+import { NativeModules } from 'react-native';
+
+const FirebaseAdMob = NativeModules.RNFirebaseAdmob;
+
+export default class Interstitial {
+
+  constructor(admob: Object, eventListener: Object, adunit: string) {
+    this.admob = admob;
+    this.adUnit = adunit;
+
+    eventListener.addListener('interstitial_event', this._onInterstitialEvent.bind(this));
+  }
+
+  _onInterstitialEvent(event) {
+
+  }
+
+  loadAd(request: AdRequest) {
+    return FirebaseAdMob.interstitialLoadAd(this.adUnit, request);
+  }
+
+  isLoaded() {
+    return true;
+  }
+
+  show() {
+    return FirebaseAdMob.interstitialShowAd(this.adUnit);
+  }
+}

lib/modules/admob/index.js

@@ -1 +1,20 @@
-export const Banner = require('./Banner');
+import Interstitial from './Interstitial';
+import AdRequest from './AdRequest';
+import Banner from './Banner';
+import Base from './../base';
+
+const FirebaseAdMob = NativeModules.RNFirebaseAdMob;
+const FirebaseAdMobEvt = new NativeEventEmitter(FirebaseAdMob);
+
+export default class Admob extends Base {
+
+  interstitial(adUnit: string) {
+    return new Interstitial(this, FirebaseAdMobEvt, adUnit);
+  }
+
+}
+
+export const statics = {
+  Banner,
+  AdRequest,
+};