/* ============================================================
   BAN YARO — Service Worker
   Offline-Cache + Push Notifications
   ============================================================ */

const CACHE_VERSION = 'by-v13';
const CACHE_STATIC  = `${CACHE_VERSION}-static`;

// Diese Dateien werden beim Install gecacht (App Shell)
const STATIC_ASSETS = [
  '/',
  '/css/design-system.css',
  '/css/layout.css',
  '/css/components.css',
  '/js/api.js',
  '/js/ui.js',
  '/js/app.js',
  '/manifest.json',
  '/icons/icon-192.png',
];

// ----------------------------------------------------------
// INSTALL — App Shell cachen
// ----------------------------------------------------------
self.addEventListener('install', event => {
  event.waitUntil(
    caches.open(CACHE_STATIC)
      .then(cache => cache.addAll(STATIC_ASSETS))
      .then(() => self.skipWaiting())
  );
});

// ----------------------------------------------------------
// ACTIVATE — alte Caches aufräumen
// ----------------------------------------------------------
self.addEventListener('activate', event => {
  event.waitUntil(
    caches.keys()
      .then(keys => Promise.all(
        keys.filter(k => k !== CACHE_STATIC).map(k => caches.delete(k))
      ))
      .then(() => self.clients.claim())
  );
});

// ----------------------------------------------------------
// FETCH — Cache-First für statische Assets, Network-First für API
// ----------------------------------------------------------
self.addEventListener('fetch', event => {
  const url = new URL(event.request.url);

  // API-Calls: immer Network, kein Cache
  if (url.pathname.startsWith('/api/')) {
    event.respondWith(
      fetch(event.request).catch(() =>
        new Response(JSON.stringify({ detail: 'Offline — keine Verbindung.' }),
          { status: 503, headers: { 'Content-Type': 'application/json' } })
      )
    );
    return;
  }

  // Statische Assets: Cache-First
  event.respondWith(
    caches.match(event.request)
      .then(cached => cached || fetch(event.request)
        .then(response => {
          // Erfolgreiche Responses für statische Assets cachen
          if (response.ok && event.request.method === 'GET') {
            const clone = response.clone();
            caches.open(CACHE_STATIC).then(c => c.put(event.request, clone));
          }
          return response;
        })
      )
      .catch(() => {
        // Offline-Fallback: App Shell zurückgeben
        if (event.request.mode === 'navigate') {
          return caches.match('/');
        }
      })
  );
});

// ----------------------------------------------------------
// PUSH NOTIFICATIONS
// ----------------------------------------------------------
self.addEventListener('push', event => {
  if (!event.data) return;

  const data = event.data.json();

  const options = {
    body:    data.body    || '',
    icon:    data.icon    || '/icons/icon-192.png',
    badge:   data.badge   || '/icons/icon-192.png',
    tag:     data.tag     || 'ban-yaro',
    data:    data.data    || {},
    actions: data.actions || [],
    vibrate: data.vibrate || [100, 50, 100],
    requireInteraction: data.requireInteraction || false,
  };

  // Giftköder-Alarm: besondere Darstellung
  if (data.type === 'poison_alert') {
    options.tag               = 'poison-alert';
    options.requireInteraction = true;
    options.vibrate           = [200, 100, 200, 100, 200];
    options.actions = [
      { action: 'view',    title: 'Auf Karte zeigen' },
      { action: 'dismiss', title: 'Verstanden'       },
    ];
  }

  event.waitUntil(
    self.registration.showNotification(data.title || 'Ban Yaro', options)
  );
});

// ----------------------------------------------------------
// NOTIFICATION CLICK
// ----------------------------------------------------------
self.addEventListener('notificationclick', event => {
  event.notification.close();

  const data   = event.notification.data;
  const action = event.action;

  let url = '/';

  if (action === 'view' || data?.page) {
    url = `/#${data.page || 'poison'}`;
    if (data.id) url += `?id=${data.id}`;
  }

  event.waitUntil(
    clients.matchAll({ type: 'window', includeUncontrolled: true })
      .then(windowClients => {
        // Offenes Fenster fokussieren
        for (const client of windowClients) {
          if (client.url.includes(self.location.origin)) {
            client.focus();
            client.navigate(url);
            return;
          }
        }
        // Neues Fenster öffnen
        return clients.openWindow(url);
      })
  );
});