Lock the e-mail on input if the code has an e-mail associated

src/pages/api/code/[id].ts

@@ -0,0 +1,23 @@
+// Next.js API route support: https://nextjs.org/docs/api-routes/introduction
+import type {NextApiRequest, NextApiResponse} from "next";
+import {app} from "@/firebase";
+import {getFirestore, collection, getDocs, query, where, setDoc, doc, getDoc, deleteDoc} from "firebase/firestore";
+import {withIronSessionApiRoute} from "iron-session/next";
+import {sessionOptions} from "@/lib/session";
+import {uuidv4} from "@firebase/util";
+
+const db = getFirestore(app);
+
+export default async function handler(req: NextApiRequest, res: NextApiResponse) {
+	if (req.method === "GET") return GET(req, res);
+
+	res.status(404).json({ok: false});
+}
+
+async function GET(req: NextApiRequest, res: NextApiResponse) {
+	const {id} = req.query;
+
+	const snapshot = await getDoc(doc(db, "codes", id as string));
+
+	res.status(200).json({...snapshot.data(), id: snapshot.id});
+}

src/pages/api/code/index.ts

@@ -48,6 +48,8 @@ async function handler(req: NextApiRequest, res: NextApiResponse) {
 		await setDoc(codeRef, {type, code, creator: req.session.user!.id, expiryDate});
 
 		if (emails && emails.length > index) {
+			await setDoc(codeRef, {email: emails[index]}, {merge: true});
+
 			const transport = prepareMailer();
 			const mailOptions = prepareMailOptions(
 				{