background.js

let ws;
let DEVICE_ID = "Desktop";
let retryTimeout = 5000; // 5s retry
let isConnecting = false;
let intervalId = null;
let listenersRegistered = false;

init();

async function init() {
  const { serverPort = 3210 } = await chrome.storage.local.get("serverPort");
  tryConnect(serverPort);
}

async function tryConnect(port) {
  if (isConnecting) return;
  isConnecting = true;

  try {
    const res = await fetch(`http://localhost:${port}/ip`, { cache: "no-store" });
    const { ip, wsPort } = await res.json();
    const SERVER = `ws://${ip}:${wsPort}`;
    console.log("Auto-connecting to:", SERVER);

    ws = new WebSocket(SERVER);

    ws.onopen = () => {
      console.log("✅ Connected to TabSync server");
      sendTabs();
      if (!intervalId) {
        intervalId = setInterval(sendTabs, 60000);
      }
      if (!listenersRegistered) {
        chrome.tabs.onRemoved.addListener(sendTabs);
        chrome.tabs.onCreated.addListener(sendTabs);
        chrome.tabs.onUpdated.addListener((tabId, changeInfo) => {
          if (
            changeInfo.status === "complete" ||
            changeInfo.url
          ) {
            sendTabs();
          }
        });

        listenersRegistered = true;
      }
      isConnecting = false;
    };

    ws.onclose = () => {
      console.warn("❌ Disconnected from TabSync server. Retrying...");
      isConnecting = false;
      setTimeout(() => tryConnect(port), retryTimeout);
    };

    ws.onerror = (err) => {
      console.error("WebSocket error:", err);
      ws.close();
    };

    ws.onmessage = (e) => console.log("Message:", e.data);
  } catch (err) {
    console.log(`TabSync Local: could not find server on port ${port}`, err);
    setTimeout(() => {
      isConnecting = false;
      tryConnect(port);
    }, retryTimeout);
  }
}

function sendTabs() {
  chrome.tabs.query({}, (tabs) => {
    if (ws && ws.readyState === WebSocket.OPEN) {
      ws.send(
        JSON.stringify({
          deviceId: DEVICE_ID,
          tabs: tabs.map((t) => ({ title: t.title, url: t.url })),
        })
      );
    }
  });
}

chrome.runtime.onMessage.addListener((msg) => {
  if (msg.action === "reconnect") {
    if (ws) ws.close();
    init(); // will read new port and reconnect
  }
});

chrome.runtime.onSuspend.addListener(() => {
  if (ws && ws.readyState === WebSocket.OPEN) {
    ws.send(
      JSON.stringify({
        deviceId: DEVICE_ID,
        tabs: [],
      })
    );
  }
});