sw.js

// SnipText service worker — makes the app installable + offline-capable.
const CACHE = "sniptext-v1";
const SHELL = [
  "./",
  "./index.html",
  "./style.css",
  "./app.js",
  "./manifest.webmanifest"
];

self.addEventListener("install", (e) => {
  e.waitUntil(caches.open(CACHE).then((c) => c.addAll(SHELL)).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())
  );
});

// Cache-first for the app shell + runtime caching (incl. the Tesseract CDN) so
// OCR works offline after the first successful run.
self.addEventListener("fetch", (e) => {
  if (e.request.method !== "GET") return;
  e.respondWith(
    caches.match(e.request).then((hit) => {
      if (hit) return hit;
      return fetch(e.request).then((res) => {
        const copy = res.clone();
        caches.open(CACHE).then((c) => c.put(e.request, copy)).catch(() => {});
        return res;
      }).catch(() => hit);
    })
  );
});