sw.js

// Focus Timer Service Worker
// Caches the app shell so it loads fast; dynamic content (sessions, log) always hits network

const CACHE_NAME = 'focus-timer-v1';

// Files to cache on install — the app shell
const SHELL = [
  './',
  './index.html',
  './manifest.json',
  './icons/icon-192.png',
  './icons/icon-512.png',
  'https://fonts.googleapis.com/css2?family=Bebas+Neue&family=DM+Sans:wght@300;400;500&display=swap'
];

// Never cache these — always fetch from network
const NETWORK_ONLY = [
  'sessions.php',
  'log.php',
  'library.php',
  'log-page.php',
  'claude-focus.php',
  'upload_video.php'
];

self.addEventListener('install', function(e) {
  e.waitUntil(
    caches.open(CACHE_NAME).then(function(cache) {
      return cache.addAll(SHELL);
    })
  );
  self.skipWaiting();
});

self.addEventListener('activate', function(e) {
  // Remove old caches
  e.waitUntil(
    caches.keys().then(function(keys) {
      return Promise.all(
        keys.filter(function(k) { return k !== CACHE_NAME; })
            .map(function(k) { return caches.delete(k); })
      );
    })
  );
  self.clients.claim();
});

self.addEventListener('fetch', function(e) {
  var url = new URL(e.request.url);

  // Network-only for PHP endpoints
  var isNetworkOnly = NETWORK_ONLY.some(function(path) {
    return url.pathname.includes(path);
  });
  if (isNetworkOnly) {
    e.respondWith(fetch(e.request));
    return;
  }

  // Cache-first for everything else (app shell, fonts)
  e.respondWith(
    caches.match(e.request).then(function(cached) {
      return cached || fetch(e.request).then(function(response) {
        // Cache successful GET responses for the shell
        if (e.request.method === 'GET' && response.status === 200) {
          var clone = response.clone();
          caches.open(CACHE_NAME).then(function(cache) {
            cache.put(e.request, clone);
          });
        }
        return response;
      });
    }).catch(function() {
      // Offline fallback — return cached index if available
      return caches.match('./index.html');
    })
  );
});