sw.js

const CACHE_NAME = "ecoatlante-demo-v2";
const APP_SHELL = [
  "./",
  "./index.html",
  "./manifest.webmanifest",
  "./favicon.svg",
  "./icons.svg",
  "./images/logo.png",
  "./images/anna.jpg",
  "./images/challenge.jpg",
  "./images/globo.png",
  "./images/sfondo_home.png",
  "./videos/datiISPRA_dvac.mp4",
];

self.addEventListener("install", (event) => {
  event.waitUntil(
    caches.open(CACHE_NAME).then((cache) => cache.addAll(APP_SHELL)).then(() => self.skipWaiting()),
  );
});

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

function isNavigationRequest(request) {
  return request.mode === "navigate" || (request.method === "GET" && request.headers.get("accept")?.includes("text/html"));
}

self.addEventListener("fetch", (event) => {
  const request = event.request;

  if (request.method !== "GET") {
    return;
  }

  const url = new URL(request.url);

  if (url.origin !== self.location.origin) {
    return;
  }

  // Network-first for navigations / HTML so the freshly deployed index.html
  // (and the hashed asset URLs it references) is always picked up. Fall back to
  // the cached shell only when offline.
  if (isNavigationRequest(request)) {
    event.respondWith(
      fetch(request)
        .then((networkResponse) => {
          const responseCopy = networkResponse.clone();
          caches.open(CACHE_NAME).then((cache) => cache.put(request, responseCopy));
          return networkResponse;
        })
        .catch(() => caches.match(request).then((cached) => cached || caches.match("./index.html"))),
    );
    return;
  }

  // Cache-first for everything else. Content-hashed assets (assets/*) change
  // name on every build, so caching them indefinitely is safe.
  event.respondWith(
    caches.match(request).then((cachedResponse) => {
      if (cachedResponse) {
        return cachedResponse;
      }

      return fetch(request).then((networkResponse) => {
        const responseCopy = networkResponse.clone();
        caches.open(CACHE_NAME).then((cache) => cache.put(request, responseCopy));
        return networkResponse;
      });
    }),
  );
});