const amqp = require("amqplib");
const nodemailer = require("nodemailer");

const {
  AMQP_URL,
  AMQP_EXCHANGE,
  AMQP_QUEUE = "email-forwarder",
  SMTP_HOST,
  SMTP_PORT = "25",
  NOTIFY_TO,
  NOTIFY_FROM = "hal@novox.be",
} = process.env;

async function main() {
  console.log(`Connecting to AMQP: ${AMQP_URL?.replace(/\/\/.*@/, "//***@")}`);
  const conn = await amqp.connect(AMQP_URL);
  const ch = await conn.createChannel();

  await ch.assertQueue(AMQP_QUEUE, { durable: true });
  await ch.bindQueue(AMQP_QUEUE, AMQP_EXCHANGE, "");
  console.log(`Bound queue '${AMQP_QUEUE}' to exchange '${AMQP_EXCHANGE}'`);

  const transport = nodemailer.createTransport({
    host: SMTP_HOST,
    port: parseInt(SMTP_PORT),
    secure: false,
    tls: { rejectUnauthorized: false },
  });

  console.log(`SMTP: ${SMTP_HOST}:${SMTP_PORT}`);
  console.log(`Forwarding to: ${NOTIFY_TO}`);
  console.log("Waiting for messages...\n");

  ch.consume(AMQP_QUEUE, async (msg) => {
    if (!msg) return;

    try {
      const headers = {};
      for (const [k, v] of Object.entries(msg.properties.headers || {})) {
        headers[k] = Buffer.isBuffer(v) ? v.toString() : v;
      }

      const body = JSON.parse(msg.content.toString());
      const subjectType = headers.subjecttype || "unknown";
      const brandCode = body.brandCode || "unknown";
      const ref = body.transactionReference || "unknown";

      const subject = `[CloudEvent] ${subjectType} / ${brandCode} / ${ref}`;
      const html = `
        <h2>CloudEvent received</h2>
        <h3>Headers</h3>
        <pre>${JSON.stringify(headers, null, 2)}</pre>
        <h3>CDM Payload</h3>
        <pre>${JSON.stringify(body, null, 2)}</pre>
        <hr>
        <p><small>From: AH BE Task Connector → ${AMQP_EXCHANGE} → ${AMQP_QUEUE}</small></p>
      `;

      await transport.sendMail({
        from: NOTIFY_FROM,
        to: NOTIFY_TO,
        subject,
        html,
      });

      console.log(`Forwarded: ${subject} → ${NOTIFY_TO}`);
      ch.ack(msg);
    } catch (err) {
      console.error("Failed to process message:", err.message);
      ch.nack(msg, false, true);
    }
  });
}

main().catch((err) => {
  console.error("Fatal:", err);
  process.exit(1);
});