!feat: added Cloudflare Turnstile captcha to the contact form

feat: added contact form disclaimer

app/_utils/sendInquiry.ts

@@ -3,6 +3,7 @@
 import { canonicalName } from "@/_data/metadata";
 import nodemailer from "nodemailer";
 import { z } from "zod";
+import { verifyTurnstile } from "./turnstile";
 
 const schema = z.object({
 	email: z.string().email().max(60),
@@ -24,6 +25,32 @@ const mailClient = nodemailer.createTransport({
 
 export default async function sendInquiry(_: FormStatus, formData: FormData): Promise<FormStatus>
 {
+	const cfToken = formData.get("cf-turnstile-response")?.toString();
+
+	if (!cfToken)
+		return {
+			status: "error",
+			message: "You must complete the challenge"
+		};
+
+	const [isValid, error] = await verifyTurnstile(cfToken);
+
+	if (!isValid)
+	{
+		if (error === "timeout-or-duplicate")
+			return {
+				status: "error",
+				message: "Challenge has expired. Try again"
+			};
+
+		console.error(error);
+
+		return {
+			status: "error",
+			message: "Something went wrong"
+		};
+	}
+
 	const { success, data } = schema.safeParse({
 		email: formData.get("email"),
 		subject: formData.get("subject"),

app/_utils/turnstile.ts

@@ -0,0 +1,51 @@
+"use server";
+
+import { headers } from "next/headers";
+
+export async function getSitekey(): Promise<string | undefined>
+{
+	return process.env.CF_SITEKEY;
+}
+
+export async function verifyTurnstile(token: string): Promise<[false, TurnstileErrorType] | [true]>
+{
+	if (!process.env.CF_SECRET)
+		return [true];
+
+	const formData = new FormData();
+
+	console.log(headers().get("CF-Connecting-IP"));
+
+	formData.append("secret", process.env.CF_SECRET);
+	formData.append("response", token);
+	formData.append("remoteip", headers().get("CF-Connecting-IP") ?? "");
+
+	const response = await fetch("https://challenges.cloudflare.com/turnstile/v0/siteverify",
+		{
+			body: formData,
+			method: "POST"
+		}
+	);
+
+	const result: TurnstileValidationResponse = await response.json();
+
+	if (result.success)
+		return [result.success];
+	else
+		return [result.success, result["error-codes"][0]];
+}
+
+export type TurnstileValidationResponse =
+	{
+		success: boolean;
+		challenge_ts: string;
+		hostname: string;
+		"error-codes": TurnstileErrorType[];
+		action: string;
+		cdata: `sessionid-${string}`;
+		metadata: Record<string, string>;
+	};
+
+export type TurnstileErrorType =
+	"missing-input-secret" | "invalid-input-secret" | "missing-input-response" |
+	"invalid-input-response" | "bad-request" | "timeout-or-duplicate" | "internal-error";