const spdy = require('spdy');
const fs = require('fs');
const app = require('express')();
const options = {
    key: fs.readFileSync(`${__dirname}/server.key`),
    cert: fs.readFileSync(`${__dirname}/server.crt`)
};
const server = spdy.createServer(options, app);

app.get('/', (req, res) => {
    const pageHTML = fs.readFileSync(`${__dirname}/index.html`);
    res.set('Content-Type', 'text/html');
    res.send(new Buffer(pageHTML));
});

server.listen(process.env.PORT || 443, () => {
    const host = server.address().address;
    const port = server.address().port;
    console.log(`Listening at: https://${host}:${port}`);
});

const server = spdy.createServer(options, app);
app.get('/', (req, res) => {
    const pageHTML = fs.readFileSync(`${__dirname}/index.html`);

    const jsOptions = {
        request: {
            accept: '*/*'
        },
        response: {
            'content-type': 'application/javascript'
        }
    };

    let stream = res.push(`/app.js`, jsOptions);
    
    stream.on('error', () => {});
    stream.write(`alert('HTTP/2 Server Push Habilitado :)');`); 
    stream.end(fs.readFileSync(`${__dirname}/app.js`));

    res.set('Content-Type', 'text/html');
    res.send(new Buffer(pageHTML));
});

// sw.js

if ('serviceWorker' in navigator) {
    navigator.serviceWorker.register('./sw-cache.js', { scope: './' })
    .then((reg) => {
        if (reg.installing) {
            console.log('Service worker installing');
        } else if (reg.waiting) {
            console.log('Service worker installed');
        } else if (reg.active) {
            console.log('Service worker active');
        }
    }).catch(function(error) {
        console.warn('Registration failed with ' + error);
    });
}

// sw-cache.js
'use strict';
const cacheVersion = 'v1';
const cacheUrls = [
    '/index.html',
    '/assets/css/style.css',
    'https://fonts.googleapis.com/css?family=Lato|Open+Sans|Roboto'
];

self.addEventListener('install', function(event) {
    event.waitUntil(
        caches.open(cacheVersion})
        .then(function(cache) {
            return cache.addAll(cacheUrls);
        })
    );
});

// sw-cache.js
self.addEventListener('activate', function(event) {
const expectedCacheNames = Object.keys(currentCaches)
    .map(key => currentCaches[key]);

event.waitUntil(
    caches.keys().then(cacheNames => {

        //Remove Cache Desatualizado
        const deletedCache = cacheNames
            .filter(cacheName => expectedCacheNames.indexOf(cacheName) == -1)
            .map(cacheName => caches.delete(cacheName));

        return Promise.all(deletedCache);
    })
);
});

// sw-cache.js
// Exemplo de Cache Seletivo
self.addEventListener('fetch', function(event) {
    event.respondWith(
        caches.open(currentCaches.font).then(cache => {
            return cache.match(event.request).then(function(response) {
                if (response) {
                    return response; //Arquivo encontrado no Cache
                }

                return fetch(event.request.clone()).then(function(response) {
                    if (response.status < 400 && response.headers.has('content-type') 
                        && response.headers.get('content-type').match('font')) {
                        //Adicionando/Atualizando Cache
                        cache.put(event.request, response.clone()); 
                    }
                    return response;
                });
            }).catch(function(error) {
                throw error;
            });
        })
    );
});