sw.js

// Minimal service worker — exists mainly to satisfy PWA installability criteria.
// This app shows live team data, so it deliberately does NOT cache or serve HTML/API
// responses offline (that would risk showing stale projects/tasks/chat to someone who
// thinks they're online).
//
// Caching strategy split in two, because most assets here have no cache-busting hash
// or version query string:
//   - CSS/JS: network-first. There's no build step, so a stale-while-revalidate here
//     would mean edits lag by an extra reload — actively confusing during development
//     and no real benefit in production either. Cache is only a fallback if offline.
//   - Images/fonts: cache-first. These essentially never change after being added, so
//     it's a safe, real performance win with no staleness risk worth worrying about.

const CACHE_NAME = 'workflow-static-v2';
const NETWORK_FIRST_RE = /\/assets\/(css|js)\//;
const CACHE_FIRST_RE = /\/assets\/(image|font)\//;

self.addEventListener('install', (event) => {
  self.skipWaiting();
});

self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches.keys().then((keys) =>
      Promise.all(keys.filter((k) => k !== CACHE_NAME).map((k) => caches.delete(k)))
    )
  );
  self.clients.claim();
});

self.addEventListener('fetch', (event) => {
  const req = event.request;
  if (req.method !== 'GET') return;

  const path = new URL(req.url).pathname;

  if (NETWORK_FIRST_RE.test(path)) {
    event.respondWith(
      fetch(req)
        .then((res) => {
          // clone() has to happen synchronously, right here, before the response
          // is returned and its body starts being consumed by the page -- doing
          // it inside the caches.open().then() callback below (the old code) ran
          // it after that consumption had already started, which is why it threw
          // "Response body is already used" on effectively every asset load.
          if (res.ok) {
            const copy = res.clone();
            caches.open(CACHE_NAME).then((c) => c.put(req, copy));
          }
          return res;
        })
        .catch(() => caches.match(req))
    );
    return;
  }

  if (CACHE_FIRST_RE.test(path)) {
    event.respondWith(
      caches.match(req).then((cached) => {
        if (cached) return cached;
        return fetch(req).then((res) => {
          if (res.ok) {
            const copy = res.clone();
            caches.open(CACHE_NAME).then((c) => c.put(req, copy));
          }
          return res;
        });
      })
    );
    return;
  }

  // everything else (HTML, api_* endpoints): let the browser handle it normally
});