import net from "net";
import dns from "dns";

export default function verifyEmailSMTP(email: string): Promise<boolean> {
    return new Promise((resolve, reject) => {
        const domain = email.split("@")[1];

        dns.resolveMx(domain, (err, addresses) => {
            if (err || !addresses.length) {
                console.log("Invalid email domain.");
                return;
            }

            const mxServer = addresses[0].exchange;
            console.log(`Connecting to ${mxServer} to verify email...`);

            const client = net.createConnection(25, mxServer);

            client.on("connect", () => {
                console.log("Connected to SMTP server.");
                client.write("HELO example.com\r\n");
                client.write(`MAIL FROM: <test@example.com>\r\n`);
                client.write(`RCPT TO: <${email}>\r\n`);
            });

            client.on("data", (data) => {
                const response = data.toString();

                if (response.includes("250")) {
                    console.log("✅ Email exists!");
                    resolve(true);
                } else {
                    console.log("❌ Email does not exist.");
                    resolve(false);
                }

                client.end();
            });

            client.on("error", (err) => {
                console.log("SMTP verification failed:", err.message);
                resolve(false);
            });
        });
    });
}