feat: Datum-Validierung, Monatsauswahl, CalDAV-Fix, wiederkehrende Termine

- End-Datum passt sich automatisch an wenn Start geändert wird (Duration bleibt erhalten)
- Erstellen-Button nutzt den aktuell angesehenen Tag statt immer heute
- Monatsansicht: Einzelklick = Tag auswählen, Doppelklick = Tagesansicht, Rechtsklick = Kontextmenü
- CalDAV URL-Matching robuster (Normalisierung, Path-Fallback, calendar_id Parameter)
- iCal-Abo-Termine sind nicht mehr bearbeitbar (Read-Only-Schutz)
- Wiederkehrende Termine mit RRULE-Support (täglich/wöchentlich/monatlich/jährlich/benutzerdefiniert)

backend/caldav_client.py

@@ -4,7 +4,7 @@ from datetime import date, datetime, timedelta, timezone
 from typing import Dict, List, Optional
 
 import caldav
-from icalendar import Calendar, Event
+from icalendar import Calendar, Event, vRecur
 
 logger = logging.getLogger(__name__)
 
@@ -105,6 +105,8 @@ def _parse_ics(raw: str, event_url: str) -> List[Dict]:
             location = str(component.get("LOCATION", "") or "")
             description = str(component.get("DESCRIPTION", "") or "")
             color = str(component.get("X-CALENDARR-COLOR", "") or "")
+            rrule_prop = component.get("RRULE")
+            rrule_str = rrule_prop.to_ical().decode("utf-8") if rrule_prop else None
 
             dtstart_prop = component.get("DTSTART")
             dtend_prop = component.get("DTEND")
@@ -154,6 +156,7 @@ def _parse_ics(raw: str, event_url: str) -> List[Dict]:
                     "location": location,
                     "description": description,
                     "color": color or None,
+                    "rrule": rrule_str,
                 }
             )
         except Exception as exc:
@@ -201,6 +204,8 @@ def create_event(
         event.add("description", data["description"])
     if data.get("color"):
         event.add("x-calendarr-color", data["color"])
+    if data.get("rrule"):
+        event.add("rrule", _parse_rrule_str(data["rrule"]))
 
     cal.add_component(event)
     cal_obj.save_event(cal.to_ical().decode("utf-8"))
@@ -247,6 +252,11 @@ def update_event(
             component["DESCRIPTION"] = data["description"]
         if "color" in data:
             component["X-CALENDARR-COLOR"] = data["color"]
+        if "rrule" in data:
+            if data["rrule"]:
+                component["RRULE"] = _parse_rrule_str(data["rrule"])
+            elif "RRULE" in component:
+                del component["RRULE"]
 
         new_cal.add_component(component)
 
@@ -260,6 +270,20 @@ def delete_event(url: str, username: str, password: str, event_url: str):
     resource.delete()
 
 
+def _parse_rrule_str(rrule_str: str) -> vRecur:
+    """Parse an RRULE string like 'FREQ=WEEKLY;BYDAY=MO,WE' into a vRecur."""
+    params = {}
+    for part in rrule_str.split(";"):
+        if "=" not in part:
+            continue
+        key, val = part.split("=", 1)
+        if "," in val:
+            params[key] = val.split(",")
+        else:
+            params[key] = val
+    return vRecur(params)
+
+
 def _parse_dt(s: str) -> datetime:
     s = s.replace("Z", "+00:00")
     dt = datetime.fromisoformat(s)

backend/main.py

@@ -83,6 +83,12 @@ def _migrate():
             conn.commit()
         except Exception:
             pass
+        try:
+            conn.execute(text("ALTER TABLE local_events ADD COLUMN rrule TEXT"))
+            conn.commit()
+            logging.info("Migration: added rrule to local_events")
+        except Exception:
+            pass
 
 _migrate()
 

backend/models.py

@@ -112,6 +112,7 @@ class LocalEvent(Base):
     location = Column(String(500), nullable=True)
     description = Column(Text, nullable=True)
     color = Column(String(7), nullable=True)
+    rrule = Column(Text, nullable=True)
 
     calendar = relationship("LocalCalendar", back_populates="events")
 

backend/routers/caldav_router.py

@@ -1,9 +1,13 @@
 import logging
+from datetime import datetime as dt_datetime, date as dt_date, timedelta, timezone as dt_timezone
 from typing import Optional
+from urllib.parse import urlparse
 
+from dateutil.rrule import rrulestr
 from fastapi import APIRouter, Depends, HTTPException, Query
 from pydantic import BaseModel
 from sqlalchemy.orm import Session
+from sqlalchemy import or_
 
 import caldav_client
 import models
@@ -41,6 +45,7 @@ class EventCreate(BaseModel):
     location: Optional[str] = None
     description: Optional[str] = None
     color: Optional[str] = None
+    rrule: Optional[str] = None
 
 
 class EventUpdate(BaseModel):
@@ -51,6 +56,7 @@ class EventUpdate(BaseModel):
     location: Optional[str] = None
     description: Optional[str] = None
     color: Optional[str] = None
+    rrule: Optional[str] = None
 
 
 def _account_dict(a: models.CalDAVAccount) -> dict:
@@ -75,16 +81,124 @@ def _account_dict(a: models.CalDAVAccount) -> dict:
     }
 
 
+def _expand_recurring_local(ev, local_cal, range_start, range_end):
+    """Expand a recurring LocalEvent into individual occurrences within the date range."""
+    results = []
+    try:
+        ev_start_str = ev.start.replace("Z", "+00:00")
+        ev_end_str = ev.end.replace("Z", "+00:00")
+
+        if ev.all_day:
+            ev_start = dt_date.fromisoformat(ev_start_str[:10])
+            ev_end = dt_date.fromisoformat(ev_end_str[:10])
+            duration = ev_end - ev_start
+            rule = rrulestr(f"RRULE:{ev.rrule}", dtstart=dt_datetime.combine(ev_start, dt_datetime.min.time()))
+            r_start = dt_datetime.combine(range_start if isinstance(range_start, dt_date) else range_start.date(), dt_datetime.min.time())
+            r_end = dt_datetime.combine(range_end if isinstance(range_end, dt_date) else range_end.date(), dt_datetime.min.time())
+            occurrences = rule.between(r_start - timedelta(days=1), r_end + timedelta(days=1), inc=True)
+            for occ in occurrences:
+                occ_start = occ.date()
+                occ_end = occ_start + duration
+                results.append({
+                    "id": ev.uid,
+                    "url": f"local://{ev.uid}",
+                    "title": ev.title,
+                    "start": occ_start.isoformat(),
+                    "end": occ_end.isoformat(),
+                    "allDay": True,
+                    "location": ev.location or "",
+                    "description": ev.description or "",
+                    "color": ev.color,
+                    "rrule": ev.rrule,
+                    "calendar_id": f"local-{local_cal.id}",
+                    "calendar_name": local_cal.name,
+                    "calendarColor": local_cal.color,
+                    "source": "local",
+                })
+        else:
+            ev_start = dt_datetime.fromisoformat(ev_start_str)
+            ev_end = dt_datetime.fromisoformat(ev_end_str)
+            if ev_start.tzinfo is None:
+                ev_start = ev_start.replace(tzinfo=dt_timezone.utc)
+            if ev_end.tzinfo is None:
+                ev_end = ev_end.replace(tzinfo=dt_timezone.utc)
+            duration = ev_end - ev_start
+            rule = rrulestr(f"RRULE:{ev.rrule}", dtstart=ev_start)
+            r_start = range_start if isinstance(range_start, dt_datetime) else dt_datetime.combine(range_start, dt_datetime.min.time(), tzinfo=dt_timezone.utc)
+            r_end = range_end if isinstance(range_end, dt_datetime) else dt_datetime.combine(range_end, dt_datetime.min.time(), tzinfo=dt_timezone.utc)
+            if r_start.tzinfo is None:
+                r_start = r_start.replace(tzinfo=dt_timezone.utc)
+            if r_end.tzinfo is None:
+                r_end = r_end.replace(tzinfo=dt_timezone.utc)
+            occurrences = rule.between(r_start - timedelta(days=1), r_end + timedelta(days=1), inc=True)
+            for occ in occurrences:
+                occ_end = occ + duration
+                results.append({
+                    "id": ev.uid,
+                    "url": f"local://{ev.uid}",
+                    "title": ev.title,
+                    "start": occ.isoformat(),
+                    "end": occ_end.isoformat(),
+                    "allDay": False,
+                    "location": ev.location or "",
+                    "description": ev.description or "",
+                    "color": ev.color,
+                    "rrule": ev.rrule,
+                    "calendar_id": f"local-{local_cal.id}",
+                    "calendar_name": local_cal.name,
+                    "calendarColor": local_cal.color,
+                    "source": "local",
+                })
+    except Exception as exc:
+        logger.warning("Error expanding recurring event %s: %s", ev.uid, exc)
+        # Fall back to single event
+        results.append({
+            "id": ev.uid, "url": f"local://{ev.uid}", "title": ev.title,
+            "start": ev.start, "end": ev.end, "allDay": ev.all_day,
+            "location": ev.location or "", "description": ev.description or "",
+            "color": ev.color, "rrule": ev.rrule,
+            "calendar_id": f"local-{local_cal.id}", "calendar_name": local_cal.name,
+            "calendarColor": local_cal.color, "source": "local",
+        })
+    return results
+
+
+def _normalize_url(url: str) -> str:
+    """Normalize URL for comparison: lowercase scheme/host, strip trailing slash."""
+    parsed = urlparse(url)
+    scheme = parsed.scheme.lower()
+    host = (parsed.hostname or '').lower()
+    port = parsed.port
+    if (scheme == 'https' and port == 443) or (scheme == 'http' and port == 80):
+        port = None
+    netloc = f"{host}:{port}" if port else host
+    path = parsed.path.rstrip('/')
+    return f"{scheme}://{netloc}{path}"
+
+
 def _find_account_for_event_url(
     event_url: str, accounts: list[models.CalDAVAccount]
 ) -> Optional[models.CalDAVAccount]:
+    norm_event = _normalize_url(event_url)
+    # Primary: match against normalized account URL
     for acc in accounts:
-        if event_url.startswith(acc.url):
+        if norm_event.startswith(_normalize_url(acc.url)):
             return acc
-    # fallback: check calendar urls
+    # Fallback: match against normalized calendar URLs
     for acc in accounts:
         for cal in acc.calendars:
-            if event_url.startswith(cal.cal_id):
+            if norm_event.startswith(_normalize_url(cal.cal_id)):
+                return acc
+    # Second fallback: path-only matching
+    event_path = urlparse(event_url).path.rstrip('/')
+    for acc in accounts:
+        acc_path = urlparse(acc.url).path.rstrip('/')
+        if acc_path and event_path.startswith(acc_path):
+            return acc
+    for acc in accounts:
+        for cal in acc.calendars:
+            cal_path = urlparse(cal.cal_id).path.rstrip('/')
+            if cal_path and event_path.startswith(cal_path):
                 return acc
     return None
 
@@ -302,27 +416,35 @@ def get_events(
             db.query(models.LocalEvent)
             .filter(
                 models.LocalEvent.calendar_id == local_cal.id,
-                models.LocalEvent.start < end,
-                models.LocalEvent.end > start,
+                or_(
+                    # Non-recurring events in range
+                    (models.LocalEvent.rrule == None) & (models.LocalEvent.start < end) & (models.LocalEvent.end > start),
+                    # Recurring events: always include so we can expand
+                    models.LocalEvent.rrule != None,
+                ),
             )
             .all()
         )
         for ev in local_events:
-            all_events.append({
-                "id": ev.uid,
-                "url": f"local://{ev.uid}",
-                "title": ev.title,
-                "start": ev.start,
-                "end": ev.end,
-                "allDay": ev.all_day,
-                "location": ev.location or "",
-                "description": ev.description or "",
-                "color": ev.color,
-                "calendar_id": f"local-{local_cal.id}",
-                "calendar_name": local_cal.name,
-                "calendarColor": local_cal.color,
-                "source": "local",
-            })
+            if ev.rrule:
+                all_events.extend(_expand_recurring_local(ev, local_cal, start_dt, end_dt))
+            else:
+                all_events.append({
+                    "id": ev.uid,
+                    "url": f"local://{ev.uid}",
+                    "title": ev.title,
+                    "start": ev.start,
+                    "end": ev.end,
+                    "allDay": ev.all_day,
+                    "location": ev.location or "",
+                    "description": ev.description or "",
+                    "color": ev.color,
+                    "rrule": None,
+                    "calendar_id": f"local-{local_cal.id}",
+                    "calendar_name": local_cal.name,
+                    "calendarColor": local_cal.color,
+                    "source": "local",
+                })
 
     # ── iCal subscription events ──────────────────────────
     ical_subs = (
@@ -403,6 +525,7 @@ def create_event(
                 "location": data.location,
                 "description": data.description,
                 "color": data.color,
+                "rrule": data.rrule,
             },
         )
         return {"uid": uid, "calendar_id": data.calendar_id}
@@ -414,6 +537,7 @@ def create_event(
 def update_event(
     event_id: str,
     event_url: str = Query(...),
+    calendar_id: Optional[int] = Query(None),
     data: EventUpdate = None,
     db: Session = Depends(get_db),
     current_user: models.User = Depends(get_current_user),
@@ -423,7 +547,18 @@ def update_event(
         .filter(models.CalDAVAccount.user_id == current_user.id)
         .all()
     )
-    account = _find_account_for_event_url(event_url, accounts)
+    account = None
+    if calendar_id is not None:
+        cal = (
+            db.query(models.Calendar)
+            .join(models.CalDAVAccount)
+            .filter(models.Calendar.id == calendar_id, models.CalDAVAccount.user_id == current_user.id)
+            .first()
+        )
+        if cal:
+            account = next((a for a in accounts if a.id == cal.account_id), None)
+    if not account:
+        account = _find_account_for_event_url(event_url, accounts)
     if not account:
         raise HTTPException(404, "Event not found or not authorized")
     try:
@@ -443,6 +578,7 @@ def update_event(
 def delete_event(
     event_id: str,
     event_url: str = Query(...),
+    calendar_id: Optional[int] = Query(None),
     db: Session = Depends(get_db),
     current_user: models.User = Depends(get_current_user),
 ):
@@ -451,7 +587,18 @@ def delete_event(
         .filter(models.CalDAVAccount.user_id == current_user.id)
         .all()
     )
-    account = _find_account_for_event_url(event_url, accounts)
+    account = None
+    if calendar_id is not None:
+        cal = (
+            db.query(models.Calendar)
+            .join(models.CalDAVAccount)
+            .filter(models.Calendar.id == calendar_id, models.CalDAVAccount.user_id == current_user.id)
+            .first()
+        )
+        if cal:
+            account = next((a for a in accounts if a.id == cal.account_id), None)
+    if not account:
+        account = _find_account_for_event_url(event_url, accounts)
     if not account:
         raise HTTPException(404, "Event not found or not authorized")
     try:

backend/routers/local_router.py

@@ -32,6 +32,7 @@ class EventCreate(BaseModel):
     location: Optional[str] = None
     description: Optional[str] = None
     color: Optional[str] = None
+    rrule: Optional[str] = None
 
 
 class EventUpdate(BaseModel):
@@ -42,6 +43,7 @@ class EventUpdate(BaseModel):
     location: Optional[str] = None
     description: Optional[str] = None
     color: Optional[str] = None
+    rrule: Optional[str] = None
 
 
 def _cal_dict(cal: models.LocalCalendar) -> dict:
@@ -64,6 +66,7 @@ def _event_dict(ev: models.LocalEvent, cal: models.LocalCalendar) -> dict:
         "location": ev.location or "",
         "description": ev.description or "",
         "color": ev.color,
+        "rrule": ev.rrule,
         "calendar_id": f"local-{cal.id}",
         "calendar_name": cal.name,
         "calendarColor": cal.color,
@@ -180,6 +183,7 @@ def create_event(
         location=data.location,
         description=data.description,
         color=data.color,
+        rrule=data.rrule,
     )
     db.add(ev)
     db.commit()
@@ -219,6 +223,8 @@ def update_event(
         ev.description = data.description
     if data.color is not None:
         ev.color = data.color
+    if data.rrule is not None:
+        ev.rrule = data.rrule if data.rrule else None
     db.commit()
     return {"ok": True}
 

frontend/css/app.css

@@ -486,6 +486,8 @@ a { color: var(--primary); text-decoration: none; }
 .month-col:last-child { border-right: none; }
 .month-col:hover { background: var(--bg-hover); }
 .month-col.today { background: rgba(66,133,244,.08); }
+.month-col.month-selected { background: var(--primary-dim); }
+.month-col.month-selected .cell-day { color: var(--primary); font-weight: 600; }
 .month-col.other-month .cell-day { color: var(--text-3); }
 .cell-day {
   font-size: 12px; font-weight: 500; color: var(--text-2);
@@ -785,6 +787,30 @@ a { color: var(--primary); text-decoration: none; }
   padding: 12px 20px; border-top: 1px solid var(--border);
 }
 
+/* ── Recurrence UI ─────────────────────────────────────── */
+.rec-weekdays { display: flex; gap: 4px; margin-top: 8px; }
+.rec-day-btn {
+  width: 36px; height: 36px; border-radius: 50%;
+  border: 1px solid var(--border); background: var(--bg-card);
+  color: var(--text-2); cursor: pointer; font-size: 12px;
+  display: flex; align-items: center; justify-content: center;
+  transition: background var(--transition), color var(--transition);
+}
+.rec-day-btn:hover { background: var(--bg-hover); }
+.rec-day-btn.active { background: var(--primary); color: #fff; border-color: var(--primary); }
+
+/* ── Day Context Menu ──────────────────────────────────── */
+.cal-context-menu {
+  position: fixed; z-index: 1000;
+  background: var(--bg-card); border: 1px solid var(--border);
+  border-radius: var(--radius-sm); box-shadow: 0 4px 16px rgba(0,0,0,.3);
+  min-width: 180px; padding: 4px 0;
+}
+.ctx-item {
+  padding: 8px 16px; font-size: 13px; color: var(--text-1); cursor: pointer;
+}
+.ctx-item:hover { background: var(--bg-hover); }
+
 /* ── Event Popup ────────────────────────────────────────── */
 .event-popup {
   position: fixed; z-index: 600;

frontend/index.html

@@ -238,6 +238,56 @@
           </div>
         </div>
       </div>
+      <div class="form-group">
+        <label id="ev-rec-label">Wiederholung</label>
+        <select id="ev-recurrence">
+          <option value="">Keine</option>
+          <option value="FREQ=DAILY">Täglich</option>
+          <option value="FREQ=WEEKLY">Wöchentlich</option>
+          <option value="FREQ=MONTHLY">Monatlich</option>
+          <option value="FREQ=YEARLY">Jährlich</option>
+          <option value="custom">Benutzerdefiniert…</option>
+        </select>
+      </div>
+      <div id="ev-recurrence-custom" class="form-group hidden">
+        <div class="form-row" style="gap:8px;align-items:center">
+          <label style="white-space:nowrap" id="ev-rec-every-label">Alle</label>
+          <input type="number" id="ev-rec-interval" value="1" min="1" max="99" style="width:60px" />
+          <select id="ev-rec-freq">
+            <option value="DAILY">Tage</option>
+            <option value="WEEKLY">Wochen</option>
+            <option value="MONTHLY">Monate</option>
+          </select>
+        </div>
+        <div id="ev-rec-weekdays" class="rec-weekdays hidden">
+          <button type="button" class="rec-day-btn" data-day="MO">Mo</button>
+          <button type="button" class="rec-day-btn" data-day="TU">Di</button>
+          <button type="button" class="rec-day-btn" data-day="WE">Mi</button>
+          <button type="button" class="rec-day-btn" data-day="TH">Do</button>
+          <button type="button" class="rec-day-btn" data-day="FR">Fr</button>
+          <button type="button" class="rec-day-btn" data-day="SA">Sa</button>
+          <button type="button" class="rec-day-btn" data-day="SU">So</button>
+        </div>
+        <div class="form-row" style="gap:8px;align-items:center;margin-top:8px">
+          <label id="ev-rec-ends-label">Endet</label>
+          <select id="ev-rec-end-type">
+            <option value="never">Nie</option>
+            <option value="count">Nach Anzahl</option>
+            <option value="until">Am Datum</option>
+          </select>
+        </div>
+        <div id="ev-rec-end-count" class="hidden" style="margin-top:4px">
+          <input type="number" id="ev-rec-count" value="10" min="1" max="999" style="width:80px" />
+          <span id="ev-rec-occ-label"> Termine</span>
+        </div>
+        <div id="ev-rec-end-until" class="hidden" style="margin-top:4px">
+          <input type="hidden" id="ev-rec-until" />
+          <div class="dt-display" id="ev-rec-until-display" tabindex="0" role="button">
+            <span class="dt-display-text">—</span>
+            <svg class="dt-display-icon" viewBox="0 0 24 24" fill="currentColor" width="16" height="16"><path d="M19 3h-1V1h-2v2H8V1H6v2H5c-1.1 0-2 .9-2 2v24a2 2 0 002 2h14a2 2 0 002-2V5c0-1.1-.9-2-2-2zm0 16H5V8h14v21zM7 10h5v5H7z"/></svg>
+          </div>
+        </div>
+      </div>
       <div class="form-group">
         <label>Kalender</label>
         <select id="ev-calendar"></select>

frontend/js/calendar.js

@@ -250,7 +250,23 @@ function renderView() {
 
   if (state.currentView === 'month') {
     renderMonth(container, state.currentDate, evs,
-      date => { state.currentDate = date; state.currentView = 'day'; updateViewButtons(); fetchAndRender(); },
+      (date, action, mouseEvent) => {
+        if (action === 'navigate') {
+          state.currentDate = date;
+          state.currentView = 'day';
+          updateViewButtons();
+          fetchAndRender();
+        } else if (action === 'context') {
+          state.currentDate = date;
+          showDayContextMenu(date, mouseEvent);
+        } else {
+          // 'select' — highlight day without navigating
+          state.currentDate = date;
+          renderMiniCal();
+          renderView();
+          updateTitle();
+        }
+      },
       showEventPopup,
       weekStartDay
     );
@@ -764,7 +780,7 @@ function bindTopbar() {
   });
 
   document.getElementById('btn-settings').onclick = openSettingsModal;
-  document.getElementById('btn-create-event').onclick = () => openNewEventModal(new Date());
+  document.getElementById('btn-create-event').onclick = () => openNewEventModal(state.currentDate);
 
   // Mouse wheel / trackpad scroll navigation – only for month & quarter
   let _wheelLast = 0;
@@ -837,6 +853,29 @@ function bindSidebar() {
   };
 }
 
+// ── Day Context Menu (month view) ────────────────────────
+function showDayContextMenu(date, mouseEvent) {
+  document.querySelectorAll('.cal-context-menu').forEach(m => m.remove());
+
+  const menu = document.createElement('div');
+  menu.className = 'cal-context-menu';
+  menu.innerHTML = `<div class="ctx-item" data-action="create">${t('ctx_create_event')}</div>`;
+
+  menu.style.left = mouseEvent.clientX + 'px';
+  menu.style.top  = mouseEvent.clientY + 'px';
+  document.body.appendChild(menu);
+
+  menu.querySelector('[data-action="create"]').onclick = () => {
+    menu.remove();
+    openNewEventModal(date);
+  };
+
+  const close = (e) => {
+    if (!menu.contains(e.target)) { menu.remove(); document.removeEventListener('click', close); }
+  };
+  setTimeout(() => document.addEventListener('click', close), 0);
+}
+
 // ── Event Popup ───────────────────────────────────────────
 function showEventPopup(ev, anchor) {
   const popup = document.getElementById('popup-event');
@@ -877,6 +916,11 @@ function showEventPopup(ev, anchor) {
   popup.style.left = Math.max(8, left) + 'px';
   popup.style.top  = Math.max(8, top)  + 'px';
 
+  // Hide edit/delete for read-only iCal subscription events
+  const isReadOnly = (ev.source === 'ical');
+  document.getElementById('popup-edit').style.display = isReadOnly ? 'none' : '';
+  document.getElementById('popup-delete').style.display = isReadOnly ? 'none' : '';
+
   document.getElementById('popup-edit').onclick = () => {
     popup.classList.add('hidden');
     openEditEventModal(ev);
@@ -921,7 +965,7 @@ function showEventPopup(ev, anchor) {
         const subId = ev.calendar_id.replace('ical-', '');
         await api.delete(`/ical/events/${subId}/${encodeURIComponent(ev.id)}`);
       } else {
-        await api.delete(`/caldav/events/${encodeURIComponent(ev.id)}?event_url=${encodeURIComponent(ev.url)}`);
+        await api.delete(`/caldav/events/${encodeURIComponent(ev.id)}?event_url=${encodeURIComponent(ev.url)}&calendar_id=${ev.calendar_id}`);
       }
       showToast(t('event_deleted'));
       fetchAndRender(true);
@@ -1005,11 +1049,13 @@ function openNewEventModal(date) {
   toggleAlldayFields(false);
   populateCalendarSelect(null);
   resetColorPicker('');
+  resetRecurrenceUI();
   document.getElementById('ev-delete').classList.add('hidden');
   openModal('modal-event');
 }
 
 function openEditEventModal(ev) {
+  if (ev.source === 'ical') { showToast(t('event_readonly'), true); return; }
   state.editingEvent = ev;
   state.selectedEventColor = ev.color || '';
 
@@ -1033,6 +1079,23 @@ function openEditEventModal(ev) {
 
   populateCalendarSelect(ev.calendar_id);
   resetColorPicker(ev.color || '');
+
+  // Recurrence
+  const rrule = ev.rrule || '';
+  const recSel = document.getElementById('ev-recurrence');
+  const customPanel = document.getElementById('ev-recurrence-custom');
+  if (!rrule) {
+    recSel.value = '';
+    customPanel.classList.add('hidden');
+  } else if (['FREQ=DAILY', 'FREQ=WEEKLY', 'FREQ=MONTHLY', 'FREQ=YEARLY'].includes(rrule)) {
+    recSel.value = rrule;
+    customPanel.classList.add('hidden');
+  } else {
+    recSel.value = 'custom';
+    customPanel.classList.remove('hidden');
+    parseRruleIntoUI(rrule);
+  }
+
   document.getElementById('ev-delete').classList.remove('hidden');
   openModal('modal-event');
 }
@@ -1050,24 +1113,142 @@ function resetColorPicker(color) {
   preview.style.background = color || 'var(--primary)';
 }
 
+function buildRruleFromUI() {
+  const sel = document.getElementById('ev-recurrence').value;
+  if (!sel) return null;
+  if (sel !== 'custom') return sel;
+
+  const interval = parseInt(document.getElementById('ev-rec-interval').value) || 1;
+  const freq = document.getElementById('ev-rec-freq').value;
+  let rule = `FREQ=${freq}`;
+  if (interval > 1) rule += `;INTERVAL=${interval}`;
+
+  if (freq === 'WEEKLY') {
+    const days = [...document.querySelectorAll('.rec-day-btn.active')].map(b => b.dataset.day);
+    if (days.length) rule += `;BYDAY=${days.join(',')}`;
+  }
+
+  const endType = document.getElementById('ev-rec-end-type').value;
+  if (endType === 'count') {
+    rule += `;COUNT=${parseInt(document.getElementById('ev-rec-count').value) || 10}`;
+  } else if (endType === 'until') {
+    const until = document.getElementById('ev-rec-until').value;
+    if (until) rule += `;UNTIL=${until.replace(/-/g, '')}T235959Z`;
+  }
+  return rule;
+}
+
+function parseRruleIntoUI(rruleStr) {
+  const parts = {};
+  rruleStr.split(';').forEach(p => {
+    const [k, v] = p.split('=', 2);
+    if (k && v) parts[k] = v;
+  });
+
+  document.getElementById('ev-rec-interval').value = parts.INTERVAL || '1';
+  document.getElementById('ev-rec-freq').value = parts.FREQ || 'DAILY';
+  document.getElementById('ev-rec-weekdays').classList.toggle('hidden', parts.FREQ !== 'WEEKLY');
+
+  // Reset all weekday buttons
+  document.querySelectorAll('.rec-day-btn').forEach(btn => btn.classList.remove('active'));
+  if (parts.BYDAY) {
+    parts.BYDAY.split(',').forEach(day => {
+      const btn = document.querySelector(`.rec-day-btn[data-day="${day.trim()}"]`);
+      if (btn) btn.classList.add('active');
+    });
+  }
+
+  if (parts.COUNT) {
+    document.getElementById('ev-rec-end-type').value = 'count';
+    document.getElementById('ev-rec-count').value = parts.COUNT;
+    document.getElementById('ev-rec-end-count').classList.remove('hidden');
+    document.getElementById('ev-rec-end-until').classList.add('hidden');
+  } else if (parts.UNTIL) {
+    document.getElementById('ev-rec-end-type').value = 'until';
+    // Parse UNTIL: 20260501T235959Z → 2026-05-01
+    const u = parts.UNTIL.replace('Z', '');
+    const formatted = u.length >= 8 ? `${u.slice(0,4)}-${u.slice(4,6)}-${u.slice(6,8)}` : '';
+    if (formatted) setDtValue('ev-rec-until', formatted, 'date');
+    document.getElementById('ev-rec-end-count').classList.add('hidden');
+    document.getElementById('ev-rec-end-until').classList.remove('hidden');
+  } else {
+    document.getElementById('ev-rec-end-type').value = 'never';
+    document.getElementById('ev-rec-end-count').classList.add('hidden');
+    document.getElementById('ev-rec-end-until').classList.add('hidden');
+  }
+}
+
+function resetRecurrenceUI() {
+  document.getElementById('ev-recurrence').value = '';
+  document.getElementById('ev-recurrence-custom').classList.add('hidden');
+  document.getElementById('ev-rec-interval').value = '1';
+  document.getElementById('ev-rec-freq').value = 'DAILY';
+  document.getElementById('ev-rec-weekdays').classList.add('hidden');
+  document.querySelectorAll('.rec-day-btn').forEach(btn => btn.classList.remove('active'));
+  document.getElementById('ev-rec-end-type').value = 'never';
+  document.getElementById('ev-rec-end-count').classList.add('hidden');
+  document.getElementById('ev-rec-end-until').classList.add('hidden');
+}
+
 function bindEventModal() {
   document.getElementById('ev-allday').addEventListener('change', e => {
     toggleAlldayFields(e.target.checked);
   });
 
-  // Date/time pickers
+  // Date/time pickers with auto-adjustment logic
   [
-    { displayId: 'ev-start-display',      inputId: 'ev-start',      mode: 'datetime' },
-    { displayId: 'ev-end-display',        inputId: 'ev-end',        mode: 'datetime' },
-    { displayId: 'ev-start-date-display', inputId: 'ev-start-date', mode: 'date'     },
-    { displayId: 'ev-end-date-display',   inputId: 'ev-end-date',   mode: 'date'     },
-  ].forEach(({ displayId, inputId, mode }) => {
+    { displayId: 'ev-start-display',      inputId: 'ev-start',      mode: 'datetime', role: 'start' },
+    { displayId: 'ev-end-display',        inputId: 'ev-end',        mode: 'datetime', role: 'end'   },
+    { displayId: 'ev-start-date-display', inputId: 'ev-start-date', mode: 'date',     role: 'start' },
+    { displayId: 'ev-end-date-display',   inputId: 'ev-end-date',   mode: 'date',     role: 'end'   },
+  ].forEach(({ displayId, inputId, mode, role }) => {
     const disp = document.getElementById(displayId);
     if (!disp) return;
     const open = async () => {
       const current = document.getElementById(inputId)?.value || '';
-      const result  = await openDatePicker(disp, current, mode);
-      if (result !== null) setDtValue(inputId, result, mode);
+      const oldStart = mode === 'datetime'
+        ? document.getElementById('ev-start').value
+        : document.getElementById('ev-start-date').value;
+      const oldEnd = mode === 'datetime'
+        ? document.getElementById('ev-end').value
+        : document.getElementById('ev-end-date').value;
+
+      const result = await openDatePicker(disp, current, mode);
+      if (result === null) return;
+      setDtValue(inputId, result, mode);
+
+      if (role === 'start') {
+        // Adjust end to maintain duration
+        if (mode === 'datetime') {
+          const os = oldStart ? new Date(oldStart) : null;
+          const oe = oldEnd ? new Date(oldEnd) : null;
+          const ns = new Date(result);
+          const duration = (os && oe && oe > os) ? (oe - os) : 3600000;
+          const ne = new Date(ns.getTime() + duration);
+          setDtValue('ev-end', toLocalDatetimeInput(ne), 'datetime');
+        } else {
+          const endVal = document.getElementById('ev-end-date').value;
+          if (!endVal || endVal < result) {
+            setDtValue('ev-end-date', result, 'date');
+          }
+        }
+      } else {
+        // Validate end is not before start
+        if (mode === 'datetime') {
+          const startVal = document.getElementById('ev-start').value;
+          if (startVal && new Date(result) <= new Date(startVal)) {
+            const corrected = new Date(new Date(startVal).getTime() + 3600000);
+            setDtValue('ev-end', toLocalDatetimeInput(corrected), 'datetime');
+            showToast(t('error_end_before_start'), true);
+          }
+        } else {
+          const startVal = document.getElementById('ev-start-date').value;
+          if (startVal && result < startVal) {
+            setDtValue('ev-end-date', startVal, 'date');
+            showToast(t('error_end_before_start'), true);
+          }
+        }
+      }
     };
     disp.addEventListener('click', open);
     disp.addEventListener('keydown', e => { if (e.key === 'Enter' || e.key === ' ') open(); });
@@ -1091,6 +1272,41 @@ function bindEventModal() {
     }
   });
 
+  // ── Recurrence UI ──────────────────────────────────────
+  const recSel = document.getElementById('ev-recurrence');
+  const customPanel = document.getElementById('ev-recurrence-custom');
+  const recFreq = document.getElementById('ev-rec-freq');
+  const weekdaysDiv = document.getElementById('ev-rec-weekdays');
+  const endTypeSel = document.getElementById('ev-rec-end-type');
+
+  recSel.addEventListener('change', () => {
+    customPanel.classList.toggle('hidden', recSel.value !== 'custom');
+  });
+
+  recFreq.addEventListener('change', () => {
+    weekdaysDiv.classList.toggle('hidden', recFreq.value !== 'WEEKLY');
+  });
+
+  document.querySelectorAll('.rec-day-btn').forEach(btn => {
+    btn.addEventListener('click', () => btn.classList.toggle('active'));
+  });
+
+  endTypeSel.addEventListener('change', () => {
+    document.getElementById('ev-rec-end-count').classList.toggle('hidden', endTypeSel.value !== 'count');
+    document.getElementById('ev-rec-end-until').classList.toggle('hidden', endTypeSel.value !== 'until');
+  });
+
+  const untilDisp = document.getElementById('ev-rec-until-display');
+  if (untilDisp) {
+    const openUntil = async () => {
+      const current = document.getElementById('ev-rec-until').value || '';
+      const result = await openDatePicker(untilDisp, current, 'date');
+      if (result !== null) setDtValue('ev-rec-until', result, 'date');
+    };
+    untilDisp.addEventListener('click', openUntil);
+    untilDisp.addEventListener('keydown', e => { if (e.key === 'Enter' || e.key === ' ') openUntil(); });
+  }
+
   document.getElementById('ev-save').onclick = async () => {
     const title = document.getElementById('ev-title').value.trim();
     if (!title) { showToast(t('error_enter_title'), true); return; }
@@ -1102,6 +1318,7 @@ function bindEventModal() {
     const loc     = document.getElementById('ev-location').value.trim();
     const desc    = document.getElementById('ev-description').value.trim();
     const color   = state.selectedEventColor;
+    const rrule   = buildRruleFromUI();
 
     let start, end;
     if (allDay) {
@@ -1127,7 +1344,7 @@ function bindEventModal() {
           );
         } else if (ev.source === 'local') {
           await api.put(`/local/events/${encodeURIComponent(ev.id)}`,
-            { title, start, end, allDay, location: loc, description: desc, color: color || null }
+            { title, start, end, allDay, location: loc, description: desc, color: color || null, rrule: rrule || '' }
           );
         } else if (ev.source === 'ical') {
           const subId = ev.calendar_id.replace('ical-', '');
@@ -1136,8 +1353,8 @@ function bindEventModal() {
           );
         } else {
           await api.put(
-            `/caldav/events/${encodeURIComponent(ev.id)}?event_url=${encodeURIComponent(ev.url)}`,
-            { title, start, end, allDay, location: loc, description: desc, color: color || null }
+            `/caldav/events/${encodeURIComponent(ev.id)}?event_url=${encodeURIComponent(ev.url)}&calendar_id=${ev.calendar_id}`,
+            { title, start, end, allDay, location: loc, description: desc, color: color || null, rrule: rrule || '' }
           );
         }
         showToast(t('event_updated'));
@@ -1153,6 +1370,7 @@ function bindEventModal() {
         await api.post('/local/events', {
           calendar_id: calId, title, start, end, allDay,
           location: loc, description: desc, color: color || null,
+          rrule: rrule || null,
         });
         showToast(t('event_created'));
       } else {
@@ -1160,6 +1378,7 @@ function bindEventModal() {
         await api.post('/caldav/events', {
           calendar_id: calId, title, start, end, allDay,
           location: loc, description: desc, color: color || null,
+          rrule: rrule || null,
         });
         showToast(t('event_created'));
       }
@@ -1184,7 +1403,7 @@ function bindEventModal() {
         const subId = ev.calendar_id.replace('ical-', '');
         await api.delete(`/ical/events/${subId}/${encodeURIComponent(ev.id)}`);
       } else {
-        await api.delete(`/caldav/events/${encodeURIComponent(ev.id)}?event_url=${encodeURIComponent(ev.url)}`);
+        await api.delete(`/caldav/events/${encodeURIComponent(ev.id)}?event_url=${encodeURIComponent(ev.url)}&calendar_id=${ev.calendar_id}`);
       }
       showToast(t('event_deleted'));
       closeModal('modal-event');

frontend/js/i18n.js

@@ -142,6 +142,15 @@ const translations = {
     error_enter_title: 'Bitte Titel eingeben',
     error_enter_date: 'Bitte Datum eingeben',
     error_enter_start: 'Bitte Start-Zeit eingeben',
+    error_end_before_start: 'Ende kann nicht vor dem Start liegen',
+    ctx_create_event: 'Neuen Termin erstellen',
+    event_readonly: 'Abonnierte Termine können nicht bearbeitet werden',
+    rec_label: 'Wiederholung',
+    rec_none: 'Keine', rec_daily: 'Täglich', rec_weekly: 'Wöchentlich',
+    rec_monthly: 'Monatlich', rec_yearly: 'Jährlich', rec_custom: 'Benutzerdefiniert…',
+    rec_every: 'Alle', rec_days: 'Tage', rec_weeks: 'Wochen', rec_months: 'Monate',
+    rec_ends: 'Endet', rec_never: 'Nie', rec_after_count: 'Nach Anzahl',
+    rec_on_date: 'Am Datum', rec_occurrences: 'Termine',
     copy_to_calendar: 'Kopieren nach…', event_copied: 'Termin kopiert',
     event_updated: 'Termin aktualisiert', event_created: 'Termin erstellt',
     confirm_delete_event: '"{title}" wirklich löschen?',
@@ -337,6 +346,15 @@ const translations = {
     error_enter_title: 'Please enter a title',
     error_enter_date: 'Please enter a date',
     error_enter_start: 'Please enter a start time',
+    error_end_before_start: 'End cannot be before start',
+    ctx_create_event: 'Create new event',
+    event_readonly: 'Subscribed events cannot be edited',
+    rec_label: 'Recurrence',
+    rec_none: 'None', rec_daily: 'Daily', rec_weekly: 'Weekly',
+    rec_monthly: 'Monthly', rec_yearly: 'Yearly', rec_custom: 'Custom…',
+    rec_every: 'Every', rec_days: 'days', rec_weeks: 'weeks', rec_months: 'months',
+    rec_ends: 'Ends', rec_never: 'Never', rec_after_count: 'After count',
+    rec_on_date: 'On date', rec_occurrences: 'occurrences',
     copy_to_calendar: 'Copy to…', event_copied: 'Event copied',
     event_updated: 'Event updated', event_created: 'Event created',
     confirm_delete_event: 'Really delete "{title}"?',

frontend/js/views/month.js

@@ -1,4 +1,4 @@
-import { isToday, isPast, dayOfWeek, weekStart, getISOWeekNumber } from '../utils.js';
+import { isToday, isPast, isSameDay, dayOfWeek, weekStart, getISOWeekNumber } from '../utils.js';
 import { t } from '../i18n.js';
 
 const LANE_H   = 20; // px per lane (event height 18px + 2px gap)
@@ -124,10 +124,11 @@ export function renderMonth(container, currentDate, events, onDayClick, onEventC
     rowCells.forEach(cell => {
       const key      = dateKey(cell);
       const isOther  = cell.getMonth() !== primaryMonth;
-      const todayCls = isToday(cell) ? 'today' : '';
-      const otherCls = isOther       ? 'other-month' : '';
-      const numCls   = isToday(cell) ? 'today' : '';
-      colsHtml += `<div class="month-col ${todayCls} ${otherCls}" data-date="${key}">
+      const todayCls    = isToday(cell) ? 'today' : '';
+      const otherCls    = isOther       ? 'other-month' : '';
+      const selectedCls = isSameDay(cell, currentDate) ? 'month-selected' : '';
+      const numCls      = isToday(cell) ? 'today' : '';
+      colsHtml += `<div class="month-col ${todayCls} ${otherCls} ${selectedCls}" data-date="${key}">
         <div class="cell-day ${numCls}">${cell.getDate()}</div>
       </div>`;
     });
@@ -148,6 +149,8 @@ export function renderMonth(container, currentDate, events, onDayClick, onEventC
 
   // Click handlers via event delegation on the body
   const body = container.querySelector('.month-body');
+
+  // Single click: select day (or handle event / more clicks)
   body.addEventListener('click', e => {
     // Span event click
     const spanEl = e.target.closest('.month-span-event');
@@ -161,13 +164,30 @@ export function renderMonth(container, currentDate, events, onDayClick, onEventC
     const moreEl = e.target.closest('.month-more');
     if (moreEl) {
       e.stopPropagation();
-      onDayClick(new Date(moreEl.dataset.date + 'T00:00:00'));
+      onDayClick(new Date(moreEl.dataset.date + 'T00:00:00'), 'navigate');
       return;
     }
-    // Column click → navigate to day view
+    // Column click → select day
     const colEl = e.target.closest('.month-col');
     if (colEl) {
-      onDayClick(new Date(colEl.dataset.date + 'T00:00:00'));
+      onDayClick(new Date(colEl.dataset.date + 'T00:00:00'), 'select');
+    }
+  });
+
+  // Double click: navigate to day view
+  body.addEventListener('dblclick', e => {
+    const colEl = e.target.closest('.month-col');
+    if (colEl && !e.target.closest('.month-span-event')) {
+      onDayClick(new Date(colEl.dataset.date + 'T00:00:00'), 'navigate');
+    }
+  });
+
+  // Right click: context menu
+  body.addEventListener('contextmenu', e => {
+    const colEl = e.target.closest('.month-col');
+    if (colEl) {
+      e.preventDefault();
+      onDayClick(new Date(colEl.dataset.date + 'T00:00:00'), 'context', e);
     }
   });
 }

requirements.txt

@@ -10,3 +10,4 @@ requests==2.32.3
 pyotp==2.9.0
 qrcode[pil]==8.0
 Pillow==11.0.0
+python-dateutil==2.9.0