'use strict';
/* ================================== */
/* NOTE: Registration done in main.js */
/* ================================== */

/* =================================== */
/* NOTE: CacheKey & FilesToCache Lists */
/* =================================== */
const version = '1';
const appPrefix = 'ohmnews-';
const staticCacheKey = appPrefix + 'static-v' + version;
const dataCacheKey = appPrefix + 'content-data';
var allCacheKey = [
        staticCacheKey,
        dataCacheKey
];

/* ================================== */
/* NOTE: Install: Save files to cache */
/* ================================== */
// Install new service worker even when old version still in use.
// Install happens only once a lifetime of a service worker.
const cacheResources = async () => {
        const staticFilesToCache = [
                './',
                'favicon.ico',
                'index.html',
                'main.js',
                'manifest.json',
                'font/flUhRq6tzZclQEJ-Vdg-IuiaDsNc.woff2',
                'font/KFOlCnqEu92Fr1MmEU9fBBc4.woff2',
                'font/KFOlCnqEu92Fr1MmEU9fChc4EsA.woff2',
                'font/KFOlCnqEu92Fr1MmSU5fBBc4.woff2',
                'font/KFOlCnqEu92Fr1MmSU5fChc4EsA.woff2',
                'font/KFOlCnqEu92Fr1MmWUlfBBc4.woff2',
                'font/KFOlCnqEu92Fr1MmWUlfChc4EsA.woff2',
                'font/KFOmCnqEu92Fr1Mu4mxK.woff2',
                'font/KFOmCnqEu92Fr1Mu7GxKOzY.woff2',
                'img/launcher/launcher_app_icon_152.png',
                'img/launcher/launcher_app_icon_167.png',
                'img/launcher/launcher_app_icon_180.png',
                'img/launcher/launcher_app_icon_192.png',
                'img/launcher/launcher_app_icon_512.png',
                'img/app_icon.png',
                'img/launcher_app_icon.png',
                'img/profil_icon.png',
                'lib/bootstrap-font-and-icons.css',
                'lib/bootstrap-material-design.js',
                'lib/bootstrap-material-design.min.css',
                'lib/jquery-3.3.1.min.js',
                'lib/popper-1.12.6.js',
                'lib/vue-router.js',
                'lib/vue.js',
                'routes/bookmark.js',
                'routes/createMessage.js',
                'routes/files.js',
                'routes/home.js',
                'routes/messageData.js',
                'routes/msgCard.js',
                'routes/profil.js',
                'routes/profilCard.js',
                'routes/profilData.js',
                'style/style.css',
        ];
        const dataFilesToCache = [];

        const cacheStatic = await caches.open(staticCacheKey);
        cacheStatic.addAll(staticFilesToCache);
        console.log('[ServiceWorker] Cache static files.');

        const cacheData = await caches.open(dataCacheKey);
        cacheData.addAll(dataFilesToCache);
        console.log('[ServiceWorker] Cache data files.');
        return;
}
self.addEventListener('install', event => {
        // don't wait
        self.skipWaiting();
        // cache static files
        event.waitUntil(cacheResources())
        console.log('[ServiceWorker] Install');
});

/* ================================================================ */
/* NOTE: Activate: new service worker and delete old cache versions */
/* ================================================================ */
// No fetch or pull is called before succesfull activate event.
const cacheCleanUp = async () => {
        const cacheKeyList = await caches.keys();
    const deletions = cacheKeyList
		.filter(key => key.startsWith(appPrefix) && !allCacheKey.includes(key))
        .map(key => {
                        caches.delete(key)
                        console.log('[ServiceWorker] Removing old cache', key);
                });
    for (const success of deletions) {
        await success;
    }
        return;
}
self.addEventListener('activate', event => {
        event.waitUntil(cacheCleanUp());
        clients.claim();
        console.log('[ServiceWorker] Activate');
});

/* ========================================= */
/* NOTE: Fetch: Update logic for cache files */
/* ========================================= */
self.addEventListener('fetch', event => {
        // Provide HTTPS URL for query data.
        const dataUrl = 'https://me.efi.th-nuernberg.de/om/';
        // Parse the URL:
        const requestURL = new URL(event.request.url);


        // Start the network request as soon as possible.
        //const networkPromise = fetch('/data.json');

        event.respondWith(
                caches.match(event.request)
                .then(cachedResponse => {
                        if (cachedResponse) {
                                return cachedResponse;
                        }
                        console.log('[ServiceWorker] Fetch', requestURL.href);
                        return fetch(event.request).then(response => {
                                // Check if we received a valid response
                                // - Ensure the response is valid.
                                // - Check the status is 200 on the response.
                                // - Make sure the response type is basic, which indicates that it's a request from our origin.
                                //   This means that requests to third party assets aren't cached as well.
                                if (!response || response.status !== 200 || response.type !== 'basic') {
                                        return response;
                                }

                                // We have to clone the response here because request bodies
                                // can only be read once. Placing a response in the cache
                                // counts as a read and so does the `res.json` call below.
                                var responseToCache = response.clone();

                                caches.open(staticCacheKey).then(cache => {
                                        cache.put(event.request, responseToCache);
                                });

                                return response;
                        });
                })
        );
});