/* EMOJESIS — minimal offline cache. Bump CACHE on every release. */
'use strict';

var CACHE = 'emojesis-v1';
var ASSETS = [
  './',
  './index.html',
  './css/style.css',
  './js/data.js',
  './js/app.js',
  './favicon.svg'
];

self.addEventListener('install', function (ev) {
  ev.waitUntil(
    caches.open(CACHE).then(function (c) { return c.addAll(ASSETS); })
      .then(function () { return self.skipWaiting(); })
  );
});

self.addEventListener('activate', function (ev) {
  ev.waitUntil(
    caches.keys().then(function (keys) {
      return Promise.all(keys.map(function (k) {
        if (k !== CACHE) return caches.delete(k);
      }));
    }).then(function () { return self.clients.claim(); })
  );
});

self.addEventListener('fetch', function (ev) {
  if (ev.request.method !== 'GET' || !ev.request.url.startsWith(self.location.origin)) return;
  ev.respondWith(
    caches.match(ev.request).then(function (hit) {
      return hit || fetch(ev.request).then(function (res) {
        if (res && res.ok) {
          var copy = res.clone();
          caches.open(CACHE).then(function (c) { c.put(ev.request, copy); });
        }
        return res;
      });
    })
  );
});