const CACHE_NAME = 'circuitjs1-app-cache-v301';

const urlsToCache = [
  '/circuit/about.html',
  '/circuit/canvas2svg.js',
  '/circuit/circuitjs.html',
  '/circuit/crystal.html',
  '/circuit/customfunction.html',
  '/circuit/customlogic.html',
  '/circuit/customtransformer.html',
  '/circuit/diodecalc.html',
  '/circuit/icon512.png',
  '/circuit/icon128.png',
  '/circuit/iframe.html',
  '/circuit/lz-string.min.js',
  '/circuit/manifest.json',
  '/circuit/mosfet-beta.html',
  '/circuit/opampreal.html',
  '/circuit/subcircuits.html',
FILE_LIST_GOES_HERE
];

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

self.addEventListener('fetch', (event) => {
    // Normalize the request URL by stripping the ?startCircuit parameter
    let req = event.request;
    const url = new URL(req.url);

    if (url.searchParams.has('startCircuit')) {
        // Remove the 'startCircuit' query parameter
        url.searchParams.delete('startCircuit');
        const request = event.request;
        req = new Request(url, {
                    method: request.method,
                    headers: request.headers,
                    mode: request.mode === 'navigate' ? 'same-origin' : request.mode,
                    credentials: request.credentials,
                    redirect: request.redirect,
                    referrer: request.referrer,
                    integrity: request.integrity,
                    cache: request.caches });
    }

    event.respondWith(
        caches.match(req).then((cachedResponse) => {
            if (cachedResponse) {
                // If the resource is already cached, return it
                return cachedResponse;
            }

            // Otherwise, fetch it from the network and add it to the cache
            return fetch(req).then((networkResponse) => {
                if (
                    event.request.method === 'GET' &&
                    networkResponse.status === 200
                ) {
                    const responseClone = networkResponse.clone();
                    caches.open(CACHE_NAME).then((cache) => {
                        cache.put(req, responseClone);
                    });
                }

                return networkResponse;
            });
        })
    );
});

// Activate event: cleans up old caches
self.addEventListener('activate', (event) => {
    const cacheWhitelist = [CACHE_NAME];  // List of cache versions you want to keep

    event.waitUntil(
        caches.keys().then((cacheNames) => {
            return Promise.all(
                cacheNames.map((cacheName) => {
                    if (!cacheWhitelist.includes(cacheName)) {
                        return caches.delete(cacheName);  // Delete old caches that aren't in whitelist
                    }
                })
            );
        })
    );
});