// Caution! Be sure you understand the caveats before publishing an application with
// offline support. See https://aka.ms/blazor-offline-considerations

self.importScripts('./service-worker-assets.js');
self.addEventListener('install', event => event.waitUntil(onInstall(event)));
self.addEventListener('activate', event => event.waitUntil(onActivate(event)));
self.addEventListener('fetch', event => event.respondWith(onFetch(event)));

const cacheNamePrefix = 'offline-cache-';
const cacheName = `${cacheNamePrefix}${self.assetsManifest.version}`;
const offlineAssetsInclude = [/\.dll$/, /\.pdb$/, /\.wasm/, /\.html/, /\.js$/, /\.json$/, /\.css$/, /\.woff$/, /\.png$/, /\.jpe?g$/, /\.gif$/, /\.ico$/, /\.blat$/, /\.dat$/, /\.webmanifest$/];
// ИСКЛЮЧАЕМ также service-worker-assets.js
const offlineAssetsExclude = [/^service-worker\.js$/, /\/service-worker-assets\.js$/];

const base = "/";
const baseUrl = new URL(base, self.origin);
const manifestUrlList = self.assetsManifest.assets.map(asset => new URL(asset.url, baseUrl).href);

async function onInstall(event) {
    self.skipWaiting();

    const assetsRequests = self.assetsManifest.assets
        .filter(asset => offlineAssetsInclude.some(pattern => pattern.test(asset.url)))
        .filter(asset => !offlineAssetsExclude.some(pattern => pattern.test(asset.url)))
        .map(asset => new Request(asset.url, { integrity: asset.hash, cache: 'no-cache' }));
    await caches.open(cacheName).then(cache => cache.addAll(assetsRequests));
}

async function onActivate(event) {
    await self.clients.claim();

    // НОВОЕ: Уведомляем все открытые вкладки о том, что новый SW активирован
    const clientsList = await self.clients.matchAll();
    clientsList.forEach(client => {
        client.postMessage({ type: 'SW_ACTIVATED', version: self.assetsManifest.version });
    });

    // Delete unused caches
    const cacheKeys = await caches.keys();
    await Promise.all(cacheKeys
        .filter(key => key.startsWith(cacheNamePrefix) && key !== cacheName)
        .map(key => caches.delete(key)));
}

async function onFetch(event) {
    // НОВОЕ: никогда не перехватываем файлы Service Worker
    const url = event.request.url;
    if (url.includes('/service-worker.js') || url.includes('/service-worker-assets.js')) {
        return fetch(event.request);
    }

    let cachedResponse = null;
    if (event.request.method === 'GET') {
        const shouldServeIndexHtml = event.request.mode === 'navigate'
            && !manifestUrlList.some(u => u === event.request.url);

        const request = shouldServeIndexHtml ? 'index.html' : event.request;
        const cache = await caches.open(cacheName);
        cachedResponse = await cache.match(request);
    }

    return cachedResponse || fetch(event.request);
}