Reader: schnelleres j/k-Scrollen; Offline-Modus auf Desktop repariert (SW v33)

j/k nutzte ein starres 8px/16ms-setInterval (~500px/s, unsauber getaktet
gegenüber dem Frame-Takt) — ersetzt durch eine requestAnimationFrame-Schleife
mit sanftem Ramp-up (700 -> 1800px/s über 300ms), das behebt sowohl die zu
niedrige Geschwindigkeit als auch das Ruckeln kurz nach Scrollbeginn.

Der Service Worker war unter /static/js/sw.js registriert, wodurch sein
Scope (mangels Service-Worker-Allowed-Header) automatisch auf /static/js/
beschränkt war statt die ganze App abzudecken — Navigationen zu z.B. /
liefen nie durch den fetch-Handler, weshalb offline nur die Browser-eigene
Fehlerseite statt der App-Shell erschien. Jetzt wird sw.js zusätzlich unter
der Root /sw.js ausgeliefert (diora/urls.py) und dort mit explizitem
scope:'/' registriert; alte Registrierungen mit dem falschen Scope werden
beim Laden automatisch entfernt.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

diora/urls.py

@@ -2,6 +2,7 @@ from django.conf import settings
 from django.conf.urls.static import static
 from django.contrib import admin
 from django.urls import path, include
+from django.views.static import serve as serve_static
 
 urlpatterns = [
     path('admin/', admin.site.urls),
@@ -9,5 +10,11 @@ urlpatterns = [
     path('podcasts/', include('podcasts.urls')),
     path('books/', include('books.urls')),
     path('api/2/', include('gpodder.urls')),
+    # Served at the root (not /static/js/sw.js) so its default scope covers
+    # the whole app — a service worker's scope is limited to its own script's
+    # directory unless the server sends Service-Worker-Allowed, so registering
+    # it from under /static/js/ silently restricted it to that subpath and
+    # navigations to '/', '/books/' etc. were never intercepted while offline.
+    path('sw.js', serve_static, {'document_root': settings.BASE_DIR / 'static' / 'js', 'path': 'sw.js'}),
     path('', include('radio.urls')),
 ] + static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

static/js/app.js

@@ -2237,14 +2237,16 @@ document.addEventListener('keydown', e => {
       const contentEl = $('reader-content');
       if (contentEl) {
         const large = Math.round(contentEl.clientHeight * 0.85);
-        const continuousKeys = {'j': 8, 'k': -8};
+        const continuousKeys = {'j': 1, 'k': -1};
         if (continuousKeys[e.key] !== undefined && !e.repeat) {
           e.preventDefault();
-          _readerScrollStep = continuousKeys[e.key];
-          if (!_readerScrollInterval) {
-            _readerScrollInterval = setInterval(() => {
-              $('reader-content')?.scrollBy({top: _readerScrollStep});
-            }, 16);
+          const dir = continuousKeys[e.key];
+          const now = performance.now();
+          if (_readerScrollDir !== dir) _readerScrollStartTs = now;
+          _readerScrollDir = dir;
+          _readerScrollLastTs = now;
+          if (!_readerScrollRaf) {
+            _readerScrollRaf = requestAnimationFrame(_readerScrollTick);
           }
         }
         if (e.key === 'd') { e.preventDefault(); contentEl.scrollBy({top:  large / 2, behavior: 'smooth'}); }
@@ -2264,8 +2266,9 @@ document.addEventListener('keydown', e => {
 
 document.addEventListener('keyup', e => {
   if (e.key === 'j' || e.key === 'k') {
-    clearInterval(_readerScrollInterval);
-    _readerScrollInterval = null;
+    if (_readerScrollRaf) cancelAnimationFrame(_readerScrollRaf);
+    _readerScrollRaf = null;
+    _readerScrollDir = 0;
   }
 });
 
@@ -2309,9 +2312,19 @@ function formatDuration(seconds) {
 
 if ('serviceWorker' in navigator) {
   window.addEventListener('load', () => {
-    navigator.serviceWorker.register('/static/js/sw.js').catch(err => {
+    // Registered from '/sw.js' (root), not '/static/js/sw.js': a service
+    // worker's default scope is its own script's directory, so registering
+    // it from under /static/js/ would only ever let it control requests
+    // under that path — page navigations to '/', '/books/' etc. would never
+    // be intercepted, breaking offline entirely.
+    navigator.serviceWorker.register('/sw.js', {scope: '/'}).catch(err => {
       console.warn('Service worker registration failed:', err);
     });
+    // Drop any leftover registration from the old, wrongly-scoped '/static/js/sw.js'
+    // path so it doesn't keep running or fight the new root-scoped worker.
+    navigator.serviceWorker.getRegistrations().then(regs => {
+      regs.forEach(r => { if (r.scope.endsWith('/static/js/')) r.unregister(); });
+    });
   });
   // When a new SW activates it sends SW_ACTIVATED — reload to get fresh assets,
   // but only if the reader isn't open (would interrupt reading).
@@ -3176,8 +3189,22 @@ let pdfTotalPages = 0;
 let _pdfPageTextBoxCache = {};
 let _pdfRenderGen = 0;
 let _touchStartX = 0;
-let _readerScrollInterval = null;
-let _readerScrollStep = 0;
+let _readerScrollRaf = null;
+let _readerScrollDir = 0;
+let _readerScrollStartTs = 0;
+let _readerScrollLastTs = 0;
+const READER_SCROLL_MIN_SPEED = 700;  // px/s right as j/k is pressed
+const READER_SCROLL_MAX_SPEED = 1800; // px/s once ramped up
+const READER_SCROLL_RAMP_MS = 300;    // time to reach max speed
+function _readerScrollTick(ts) {
+  const dt = ts - _readerScrollLastTs;
+  _readerScrollLastTs = ts;
+  const held = ts - _readerScrollStartTs;
+  const t = Math.min(held / READER_SCROLL_RAMP_MS, 1);
+  const speed = READER_SCROLL_MIN_SPEED + (READER_SCROLL_MAX_SPEED - READER_SCROLL_MIN_SPEED) * t;
+  $('reader-content')?.scrollBy({top: _readerScrollDir * speed * dt / 1000});
+  _readerScrollRaf = requestAnimationFrame(_readerScrollTick);
+}
 let _pinchStartDist = 0;
 let _pinchStartZoom = 100;
 let _isPinching = false;

static/js/sw.js

@@ -2,7 +2,7 @@
  * diora service worker — caches the app shell for offline use.
  */
 
-const CACHE = 'diora-v32';
+const CACHE = 'diora-v33';
 const PODCAST_CACHE = 'diora-podcast-v1';
 const SHELL = [
   '/static/css/app.css',