adding email check to avoid duplicates (#26)

Co-authored-by: Visakh Vijayan <visakh.vijayan@jalantechnologies.com>

src/components/main/main.component.tsx

@@ -12,7 +12,7 @@ import { getQuoteFromGemini } from "../../services/gemini";
 import { QuoteResponse } from "../../types/common";
 import { getQuoteFromNinja } from "../../services/ninja";
 import { Input } from "baseui/input";
-import { addSubscriber } from "../../services/firebase";
+import { addSubscriber, isSubscribedAlready } from "../../services/firebase";
 
 let firstLoad = true;
 
@@ -84,6 +84,14 @@ export const Main = () => {
         setIsEmailValid(true);
 
         setIsButtonLoading(true);
+
+        if (await isSubscribedAlready(email)) {
+            localStorage.setItem('isSubscribed', 'true');
+            setIsSubscribed(true);
+            setIsButtonLoading(false);
+            return;
+        }
+
         await addSubscriber(email).then(() => {
             setEmail('');
             localStorage.setItem('isSubscribed', 'true');

src/services/firebase.ts

@@ -1,5 +1,5 @@
 import { initializeApp } from "firebase/app";
-import { getFirestore, collection, addDoc } from 'firebase/firestore'
+import { getFirestore, collection, addDoc, getDocs, where, query } from 'firebase/firestore'
 
 const firebaseConfig = {
   apiKey: process.env.REACT_APP_FIREBASE_API_KEY,
@@ -19,4 +19,12 @@ export const addSubscriber = async (email: string) => {
     email,
     status: 'ACTIVE'
   });
+}
+
+export const isSubscribedAlready = async (email: string) => {
+  const querySnapshot = await getDocs(
+    query(collection(db, 'subscribers'), where('email', '==', email))
+  );
+
+  return !querySnapshot.empty;
 }