calender stuff

README.md

@@ -119,7 +119,11 @@ hyprcrd/
 - **Split view** showing tag-related and content-related cards
 - **Import/Export** as JSON+media ZIP or Obsidian/Logseq-compatible markdown vault
 - **Drag & drop** card reordering and grouping
-- **Keyboard shortcuts**: `Ctrl+K` search, `Shift+scroll` zoom, arrow keys in autocomplete
+- **Calendar** with month view, journal entries, appointments, and day popup
+- **CalDAV sync** with ownCloud/Nextcloud (bidirectional, `#termin` tagged cards)
+- **Inline calculator** (`?3+5` → `8`, `34+56?` → `34+56=90`)
+- **Snippets** (`?dat`, `?time`, `?now`, `?todo`, `?table`, `?code`, ...)
+- **Keyboard shortcuts**: `Ctrl+K` search, `F1` help, `Shift+scroll` zoom, arrow keys in autocomplete
 
 ## Data & Backup
 
@@ -141,6 +145,65 @@ Back up both to preserve everything. The database auto-migrates on startup.
     image.jpg
   ```
 
+## CalDAV Sync (ownCloud / Nextcloud)
+
+hyprcrd can sync appointment cards with any CalDAV server (tested with ownCloud 10.15.3.0).
+
+### Setup
+
+1. Open the **calendar** (button in header)
+2. Click the **gear icon** in the calendar header
+3. Enter your CalDAV URL, username, and app password:
+   ```
+   URL: https://cloud.example.com/remote.php/dav/calendars/your-user/personal/
+   Username: your-user
+   Password: your-app-password
+   ```
+4. Click **test** to verify the connection
+5. Click **save**
+
+### How it works
+
+- Cards tagged with `#termin` are synced as calendar events
+- The appointment card template maps to iCalendar fields:
+  ```markdown
+  Title: 2026-04-15 — Team Meeting
+
+  **Zeit:** 14:30-15:30
+  **Ort:** Room 42
+  **Teilnehmer:** Alice, Bob
+
+  ---
+
+  **Notizen:**
+  Agenda items here
+
+  #termin
+  ```
+- **Sync is bidirectional**: local changes push to the server, remote changes pull to hyprcrd
+- **Conflict resolution**: last-modified timestamp wins
+- **Deleted cards**: tracked via tombstones, deleted on the server on next sync
+- **Auto-sync**: triggers when opening the calendar (max once per minute)
+- **Manual sync**: click the cloud icon in the calendar header
+
+### Security
+
+- Credentials are encrypted at rest (AES-256-CBC) in the SQLite database
+- All sync operations run server-side (PHP/cURL), no client-side credential exposure
+- Supports HTTPS with certificate verification
+
+## Calendar
+
+The built-in calendar shows cards on their dates:
+
+- **Journal cards** (title = `2026-04-08`) appear on that date
+- **Appointment cards** (title = `2026-04-08 — Subject`) appear on their date
+- **Other cards** fall back to their creation date
+- **Click a day** to see all cards in a popup
+- **Double-click** or use **+ journal** / **+ termin** to create new entries
+- Appointment template includes Zeit, Ort, Teilnehmer, Notizen fields
+- Navigate months with arrow buttons, **today** jumps to current date
+
 ## Rebuilding Tailwind CSS
 
 After changing Tailwind utility classes in HTML or JS files: