sw.js

const CACHE = 'inventario-v29.2.0';

const APP_SHELL = [
  './',
  './index.html',
  './manifest.json',
  './icon-192.png',
  './icon-512.png',
];

const CDN_ASSETS = [
  'https://unpkg.com/react@18/umd/react.production.min.js',
  'https://unpkg.com/react-dom@18/umd/react-dom.production.min.js',
  'https://unpkg.com/@babel/standalone/babel.min.js',
  'https://cdn.tailwindcss.com',
  'https://cdnjs.cloudflare.com/ajax/libs/xlsx/0.18.5/xlsx.full.min.js',
  'https://cdnjs.cloudflare.com/ajax/libs/jsbarcode/3.11.5/JsBarcode.all.min.js',
  'https://cdnjs.cloudflare.com/ajax/libs/qrcodejs/1.0.0/qrcode.min.js',
  'https://unpkg.com/@zxing/library@0.19.1/umd/index.min.js',
  'https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500;600&family=IBM+Plex+Sans:wght@400;500;600;700&display=swap',
];

self.addEventListener('install', e => {
  e.waitUntil(
    caches.open(CACHE).then(cache =>
      Promise.allSettled(
        [...APP_SHELL, ...CDN_ASSETS].map(url =>
          fetch(url, { mode: url.startsWith('http') ? 'cors' : 'same-origin' })
            .then(r => { if (r.ok) cache.put(url, r); })
            .catch(() => {})
        )
      )
    ).then(() => self.skipWaiting())
  );
});

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

self.addEventListener('fetch', e => {
  const url = e.request.url;
  const isCDN = CDN_ASSETS.some(a => url.startsWith(a.split('?')[0]));

  // CDN: cache-first, refresh cache in background on success
  if (isCDN) {
    e.respondWith(
      caches.match(e.request).then(cached => {
        if (cached) return cached;
        return fetch(e.request).then(r => {
          if (r.ok) { const clone = r.clone(); caches.open(CACHE).then(c => c.put(e.request, clone)); }
          return r;
        }).catch(() => new Response('', { status: 503 }));
      })
    );
    return;
  }

  // Navegação: network-first, cai para cache/index.html offline
  if (e.request.mode === 'navigate') {
    e.respondWith(
      fetch(e.request).then(r => {
        const clone = r.clone();
        caches.open(CACHE).then(c => c.put(e.request, clone));
        return r;
      }).catch(() =>
        caches.match(e.request).then(cached => cached || caches.match('./index.html'))
      )
    );
    return;
  }

  // Restantes pedidos same-origin (manifest, ícones): cache-first com fallback à rede
  e.respondWith(
    caches.match(e.request).then(cached => cached || fetch(e.request).catch(() => cached))
  );
});