const CACHE_NAME = "flight-lookup-v1";
const ASSETS = [
  "./",
  "./index.html",
  "./style.css",
  "./data.js",
  "./app.js",
  "./manifest.json"
];

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

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

self.addEventListener("fetch", (event) => {
  const { request } = event;
  if (request.method !== "GET") return;

  event.respondWith(
    caches.match(request).then((cached) => {
      if (cached) return cached;
      return fetch(request)
        .then((response) => {
          if (response.ok && request.url.startsWith(self.location.origin)) {
            const clone = response.clone();
            caches.open(CACHE_NAME).then((cache) => cache.put(request, clone));
          }
          return response;
        })
        .catch(() => caches.match("./index.html"));
    })
  );
});