/* NestQuest Admin service worker — hand-written, served from the site root.
   Precaches the app shell, serves static assets cache-first, and falls back
   to the cached shell for navigations when offline. Only same-origin GET
   requests are handled; cross-origin requests (Authentik, the API host) are
   never intercepted or cached.
   The build (vite-sw-plugin.ts) replaces PRECACHE_ASSETS with the hashed
   bundles referenced by index.html and the revision marker with a content
   hash, so each release installs a new worker with fresh caches. */

const REVISION = "__NQ_BUILD_REVISION__";
const CACHE_PREFIX = "nestquest-admin-";
const SHELL_CACHE = `${CACHE_PREFIX}shell-${REVISION}`;
const RUNTIME_CACHE = `${CACHE_PREFIX}runtime-${REVISION}`;
const CURRENT_CACHES = [SHELL_CACHE, RUNTIME_CACHE];

const PRECACHE_ASSETS = [];

const SHELL_URLS = [
  ...new Set([
    "/",
    "/index.html",
    "/manifest.webmanifest",
    "/icons/icon-192.png",
    "/icons/icon-512.png",
    "/icons/icon-maskable-512.png",
    ...PRECACHE_ASSETS,
  ]),
];

// Request destinations treated as static assets (cache-first). Anything else
// same-origin (e.g. API calls) goes straight to the network.
const STATIC_DESTINATIONS = ["script", "style", "image", "font", "manifest"];

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

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

self.addEventListener("fetch", (event) => {
  const request = event.request;
  if (request.method !== "GET") return;
  if (new URL(request.url).origin !== self.location.origin) return;

  if (request.mode === "navigate") {
    event.respondWith(
      fetch(request).catch(() =>
        caches.match("/index.html", { cacheName: SHELL_CACHE }).then(
          (cached) => cached || Response.error(),
        ),
      ),
    );
    return;
  }

  if (STATIC_DESTINATIONS.includes(request.destination)) {
    event.respondWith(cacheFirst(request));
  }
});

async function cacheFirst(request) {
  const cached = await caches.match(request);
  if (cached) return cached;
  const response = await fetch(request);
  if (response.ok && response.type === "basic") {
    const cache = await caches.open(RUNTIME_CACHE);
    await cache.put(request, response.clone());
  }
  return response;
}