/**
 * Simple proof-of-concept NATS subscriber
 * Subscribes to mm.16.> and replies with "hello world"
 */

import { connect, StringCodec } from "nats";
import { logger } from "../../services/reporting-service/index.js";

const sc = StringCodec();

async function startTestSubscriber() {
  try {
    // Connect to NATS server
    const nc = await connect({
      servers: "nats://localhost:4222",
      name: "mm-erp-sdk-test-subscriber",
    });

    logger.info("Connected to NATS server", {
      server: nc.getServer(),
      clientId: nc.info?.client_id,
    });

    // Subscribe to all messages on mm.16.>
    const sub = nc.subscribe("mm.16.>");

    logger.info("Subscribed to mm.16.> - waiting for messages...");

    // Process incoming messages
    (async () => {
      for await (const msg of sub) {
        const data = sc.decode(msg.data);
        
        logger.info("📨 Received NATS message", {
          subject: msg.subject,
          data: data,
          reply: msg.reply,
        });

        console.log("\n=== NATS MESSAGE RECEIVED ===");
        console.log("Subject:", msg.subject);
        console.log("Data:", data);
        console.log("Reply subject:", msg.reply);
        console.log("============================\n");

        // Reply if there's a reply subject
        if (msg.reply) {
          const replyMessage = JSON.stringify({
            message: "hello world",
            timestamp: new Date().toISOString(),
            receivedSubject: msg.subject,
            receivedData: data,
          });

          msg.respond(sc.encode(replyMessage));
          
          logger.info("✅ Sent reply: hello world", {
            replySubject: msg.reply,
          });
          
          console.log("✅ Replied with: hello world\n");
        }
      }
    })();

    // Handle connection events
    (async () => {
      for await (const status of nc.status()) {
        logger.info("NATS connection status", {
          type: status.type,
          data: status.data,
        });
        console.log(`Connection status: ${status.type}`, status.data);
      }
    })();

    // Graceful shutdown
    const shutdown = async () => {
      logger.info("Shutting down NATS subscriber...");
      await nc.drain();
      process.exit(0);
    };

    process.on("SIGINT", shutdown);
    process.on("SIGTERM", shutdown);

  } catch (error) {
    logger.error("Failed to connect to NATS", { error });
    console.error("Error connecting to NATS:", error);
    process.exit(1);
  }
}

// Start the subscriber
startTestSubscriber();