pipeline

Re-enable build/test/format pipelines, rename deploy_server to
deploy_latest, add upload_tag (tag-triggered k3s deploy) and
upload_commit (promote-triggered k3s deploy). Update CLAUDE.md.

.dockerignore

@@ -0,0 +1,8 @@
+node_modules
+*/node_modules
+*/*/node_modules
+**/dist
+apps/client
+.git
+.env
+*.md

.drone.yml

@@ -0,0 +1,171 @@
+kind: pipeline
+type: docker
+name: server_build_and_test
+
+trigger:
+  branch:
+    - main
+  event:
+    - push
+
+steps:
+  - name: build_server
+    image: node
+    commands:
+      - npm ci -w @calchat/shared
+      - npm ci -w @calchat/server
+      - npm run build -w @calchat/server
+
+  - name: jest_server
+    image: node
+    commands:
+      - npm run test -w @calchat/server
+
+---
+
+kind: pipeline
+type: docker
+name: check_for_formatting
+
+trigger:
+  branch:
+    - main
+  event:
+    - push
+
+steps:
+  - name: format_check
+    image: node
+    commands:
+      - npm ci
+      - npm run check_format
+
+---
+
+kind: pipeline
+type: docker
+name: deploy_latest
+
+trigger:
+  branch:
+    - main
+  event:
+    - push
+
+steps:
+  - name: upload_latest
+    image: plugins/docker
+    settings:
+      registry: gitea.gilmour109.de
+      repo: gitea.gilmour109.de/gilmour109/calchat-server
+      dockerfile: apps/server/docker/Dockerfile
+      tags:
+        - latest
+      username:
+        from_secret: gitea_username
+      password:
+        from_secret: gitea_password
+
+  - name: deploy_to_vps
+    image: appleboy/drone-ssh
+    settings:
+      host:
+        - 10.0.0.1
+      username: root
+      password:
+        from_secret: vps_ssh_password
+      envs:
+        - gitea_username
+        - gitea_password
+      port: 22
+      command_timeout: 2m
+      script:
+        - docker login -u $GITEA_USERNAME -p $GITEA_PASSWORD gitea.gilmour109.de
+        - docker pull gitea.gilmour109.de/gilmour109/calchat-server:latest
+        - docker compose -f /root/calchat-mongo/docker-compose.yml up -d
+
+depends_on:
+  - server_build_and_test
+  - check_for_formatting
+
+---
+
+kind: pipeline
+type: docker
+name: upload_tag
+
+trigger:
+  event:
+    - tag
+
+steps:
+  - name: upload_tag
+    image: plugins/docker
+    settings:
+      registry: gitea.gilmour109.de
+      repo: gitea.gilmour109.de/gilmour109/calchat-server
+      dockerfile: apps/server/docker/Dockerfile
+      tags:
+        - ${DRONE_TAG}
+      username:
+        from_secret: gitea_username
+      password:
+        from_secret: gitea_password
+
+  - name: deploy_to_k3s
+    image: appleboy/drone-ssh
+    settings:
+      host:
+        - 192.168.178.201
+      username: debian
+      password:
+        from_secret: k3s_ssh_password
+      envs:
+        - drone_tag
+      port: 22
+      command_timeout: 2m
+      script:
+        - export TAG=$DRONE_TAG
+        - export NAME=$(echo $DRONE_TAG | tr -d '.')
+        - envsubst < /home/debian/manifest.yml | sudo kubectl apply -f -
+
+---
+
+kind: pipeline
+type: docker
+name: upload_commit
+
+trigger:
+  event:
+    - promote
+
+steps:
+  - name: upload_commit
+    image: plugins/docker
+    settings:
+      registry: gitea.gilmour109.de
+      repo: gitea.gilmour109.de/gilmour109/calchat-server
+      dockerfile: apps/server/docker/Dockerfile
+      tags:
+        - ${DRONE_COMMIT_SHA:0:8}
+      username:
+        from_secret: gitea_username
+      password:
+        from_secret: gitea_password
+
+  - name: deploy_to_k3s
+    image: appleboy/drone-ssh
+    settings:
+      host:
+        - 192.168.178.201
+      username: debian
+      password:
+        from_secret: k3s_ssh_password
+      envs:
+        - drone_commit_sha
+      port: 22
+      command_timeout: 2m
+      script:
+        - export TAG=$(echo $DRONE_COMMIT_SHA | cut -c1-8)
+        - export NAME=$TAG
+        - envsubst < /home/debian/manifest.yml | sudo kubectl apply -f -

.gitignore

@@ -3,3 +3,5 @@ node_modules
 docs/praesi_2_context.md
 docs/*.png
 .env
+apps/server/docker/radicale/config/
+apps/server/docker/radicale/data/

CLAUDE.md

@@ -14,22 +14,30 @@ This is a fullstack TypeScript monorepo with npm workspaces.
 ```bash
 npm install          # Install all dependencies for all workspaces
 npm run format       # Format all TypeScript files with Prettier
+npm run check_format # Check formatting without modifying files (used in CI)
 ```
 
 ### Client (apps/client) - Expo React Native app
 ```bash
-npm run start -w @caldav/client        # Start Expo dev server
+npm run start -w @calchat/client        # Start Expo dev server
-npm run android -w @caldav/client      # Start on Android
+npm run android -w @calchat/client      # Start on Android
-npm run ios -w @caldav/client          # Start on iOS
+npm run ios -w @calchat/client          # Start on iOS
-npm run web -w @caldav/client          # Start web version
+npm run web -w @calchat/client          # Start web version
-npm run lint -w @caldav/client         # Run ESLint
+npm run lint -w @calchat/client         # Run ESLint
+npm run build:apk -w @calchat/client    # Build APK locally with EAS
+```
+
+### Shared (packages/shared)
+```bash
+npm run build -w @calchat/shared        # Compile shared types to dist/
 ```
 
 ### Server (apps/server) - Express.js backend
 ```bash
-npm run dev -w @caldav/server          # Start dev server with hot reload (tsx watch)
+npm run dev -w @calchat/server          # Build shared + start dev server with hot reload (tsx watch)
-npm run build -w @caldav/server        # Compile TypeScript
+npm run build -w @calchat/server        # Build shared + compile TypeScript
-npm run start -w @caldav/server        # Run compiled server (port 3000)
+npm run start -w @calchat/server        # Run compiled server (port 3000)
+npm run test -w @calchat/server         # Run Jest unit tests
 ```
 
 ## Technology Stack
@@ -42,20 +50,28 @@ npm run start -w @caldav/server        # Run compiled server (port 3000)
 | | NativeWind | Tailwind CSS for React Native |
 | | Zustand | State management |
 | | FlashList | High-performance lists |
+| | EAS Build | Local APK/IPA builds |
 | Backend | Express.js | Web framework |
 | | MongoDB | Database |
 | | Mongoose | ODM |
 | | GPT (OpenAI) | AI/LLM for chat |
-| | JWT | Authentication |
+| | X-User-Id Header | Authentication |
+| | pino / pino-http | Structured logging |
+| | react-native-logs | Client-side logging |
+| | tsdav | CalDAV client library |
+| | ical.js | iCalendar parsing/generation |
+| Testing | Jest / ts-jest | Server unit tests |
+| Deployment | Docker | Server containerization (multi-stage build) |
+| | Drone CI | CI/CD pipelines (build, test, format check, deploy) |
 | Planned | iCalendar | Event export/import |
 
 ## Architecture
 
 ### Workspace Structure
 ```
-apps/client      - @caldav/client - Expo React Native app
+apps/client      - @calchat/client - Expo React Native app
-apps/server      - @caldav/server - Express.js backend
+apps/server      - @calchat/server - Express.js backend
-packages/shared  - @caldav/shared - Shared TypeScript types and models
+packages/shared  - @calchat/shared - Shared TypeScript types and models
 ```
 
 ### Frontend Architecture (apps/client)
@@ -68,61 +84,194 @@ src/
 │   ├── login.tsx               # Login screen
 │   ├── register.tsx            # Registration screen
 │   ├── (tabs)/                 # Tab navigation group
-│   │   ├── _layout.tsx         # Tab bar configuration
+│   │   ├── _layout.tsx         # Tab bar configuration (themed)
 │   │   ├── chat.tsx            # Chat screen (AI conversation)
-│   │   └── calendar.tsx        # Calendar overview
+│   │   ├── calendar.tsx        # Calendar overview (with CalendarToolbar: sync + logout)
+│   │   └── settings.tsx        # Settings screen (theme switcher, logout, CalDAV config with feedback)
+│   ├── editEvent.tsx           # Event edit screen (dual-mode: calendar/chat)
 │   ├── event/
 │   │   └── [id].tsx            # Event detail screen (dynamic route)
 │   └── note/
 │       └── [id].tsx            # Note editor for event (dynamic route)
 ├── components/
-│   ├── BaseBackground.tsx      # Common screen wrapper
+│   ├── AuthGuard.tsx           # Auth wrapper: loads user, preloads app data (events + CalDAV config), CalDAV sync, shows loading, redirects if unauthenticated. Exports preloadAppData()
-│   ├── Header.tsx              # Header component
+│   ├── BaseBackground.tsx      # Common screen wrapper (themed)
-│   ├── EventCardBase.tsx       # Shared event card layout with icons (used by EventCard & ProposedEventCard)
+│   ├── BaseButton.tsx          # Reusable button component (themed, supports children)
+│   ├── Header.tsx              # Header component (themed)
+│   ├── AuthButton.tsx          # Reusable button for auth screens (themed, with shadow)
+│   ├── CardBase.tsx            # Reusable card component (header + content + optional footer)
+│   ├── ModalBase.tsx           # Reusable modal with backdrop (uses CardBase, click-outside-to-close)
+│   ├── ChatBubble.tsx          # Reusable chat bubble component (used by ChatMessage & TypingIndicator)
+│   ├── TypingIndicator.tsx     # Animated typing indicator (. .. ...) shown while waiting for AI response
+│   ├── EventCardBase.tsx       # Event card layout with icons (uses CardBase)
 │   ├── EventCard.tsx           # Calendar event card (uses EventCardBase + edit/delete buttons)
-│   ├── EventConfirmDialog.tsx  # AI-proposed event confirmation modal
+│   ├── EventConfirmDialog.tsx  # AI-proposed event confirmation modal (skeleton)
-│   └── ProposedEventCard.tsx   # Chat event proposal (uses EventCardBase + confirm/reject buttons)
+│   ├── ProposedEventCard.tsx   # Chat event proposal (uses EventCardBase + confirm/reject/edit buttons)
-├── Themes.tsx                  # Centralized color/theme definitions
+│   ├── DeleteEventModal.tsx    # Delete confirmation modal (uses ModalBase)
+│   ├── CustomTextInput.tsx     # Themed text input with focus border (used in login, register, CaldavSettings, editEvent)
+│   ├── DateTimePicker.tsx      # Date and time picker components
+│   └── ScrollableDropdown.tsx  # Scrollable dropdown component
+├── Themes.tsx                  # Theme definitions: THEMES object with defaultLight/defaultDark, Theme type
+├── logging/
+│   ├── index.ts                # Re-exports
+│   └── logger.ts               # react-native-logs config (apiLogger, storeLogger)
 ├── services/
 │   ├── index.ts                # Re-exports all services
-│   ├── ApiClient.ts            # HTTP client (get, post, put, delete)
+│   ├── ApiClient.ts            # HTTP client with X-User-Id header injection, request logging, handles empty responses (204)
-│   ├── AuthService.ts          # login(), register(), logout(), refresh()
+│   ├── AuthService.ts          # login(), register(), logout() - calls API and updates AuthStore
-│   ├── EventService.ts         # getAll(), getById(), getByDateRange(), create(), update(), delete()
+│   ├── EventService.ts         # getAll(), getById(), getByDateRange(), create(), update(), delete(mode, occurrenceDate)
-│   └── ChatService.ts          # sendMessage(), confirmEvent(), rejectEvent(), getConversations(), getConversation()
+│   ├── ChatService.ts          # sendMessage(), confirmEvent(deleteMode, occurrenceDate), rejectEvent(), getConversations(), getConversation(), updateProposalEvent()
-└── stores/                     # Zustand state management
+│   └── CaldavConfigService.ts  # saveConfig(), getConfig(), deleteConfig(), pull(), pushAll(), sync()
-    ├── index.ts                # Re-exports all stores
+├── stores/                     # Zustand state management
-    ├── AuthStore.ts            # user, token, isAuthenticated, login(), logout(), setToken()
+│   ├── index.ts                # Re-exports all stores
-    ├── ChatStore.ts            # messages[], addMessage(), addMessages(), updateMessage(), clearMessages(), chatMessageToMessageData()
+│   ├── AuthStore.ts            # user, isAuthenticated, isLoading, login(), logout(), loadStoredUser()
-    └── EventsStore.ts          # events[], setEvents(), addEvent(), updateEvent(), deleteEvent()
+│   │                           # Uses expo-secure-store (native) / localStorage (web)
+│   ├── ChatStore.ts            # messages[], isWaitingForResponse, addMessage(), addMessages(), updateMessage(), clearMessages(), setWaitingForResponse(), chatMessageToMessageData()
+│   ├── EventsStore.ts          # events[], setEvents(), addEvent(), updateEvent(), deleteEvent()
+│   ├── CaldavConfigStore.ts    # config (CaldavConfig | null), setConfig() - cached CalDAV config
+│   └── ThemeStore.ts           # theme, setTheme() - reactive theme switching with Zustand
+└── hooks/
+    └── useDropdownPosition.ts  # Hook for positioning dropdowns relative to trigger element
 ```
 
-**Routing:** Tab-based navigation with Chat and Calendar as main screens. Auth screens (login, register) outside tabs. Dynamic routes for event detail and note editing.
+**Routing:** Tab-based navigation with Chat, Calendar, and Settings as main screens. Auth screens (login, register) outside tabs. Dynamic routes for event detail and note editing.
+
+**Authentication Flow:**
+- `AuthGuard` component wraps the tab layout in `(tabs)/_layout.tsx`
+- On app start, `AuthGuard` calls `loadStoredUser()` and shows loading indicator
+- After auth, `preloadAppData()` loads events (current month) + CalDAV config into stores before dismissing spinner
+- If not authenticated, redirects to `/login`
+- `login.tsx` also calls `preloadAppData()` after successful login (spinner stays visible during preload)
+- `index.tsx` simply redirects to `/(tabs)/chat` - AuthGuard handles the rest
+- This pattern handles Expo Router's navigation state caching (avoids race conditions)
+- Preloading prevents empty screens when navigating to Calendar or Settings tabs for the first time
+
+### Theme System
+
+The app supports multiple themes (light/dark) via a reactive Zustand store.
+
+**Theme Structure (`Themes.tsx`):**
+```typescript
+export type Theme = {
+  chatBot, primeFg, primeBg, secondaryBg, messageBorderBg, placeholderBg,
+  calenderBg, confirmButton, rejectButton, disabledButton, buttonText,
+  textPrimary, textSecondary, textMuted, eventIndicator, borderPrimary, shadowColor
+};
+
+export const THEMES = {
+  defaultLight: { ... },
+  defaultDark: { ... }
+} as const satisfies Record<string, Theme>;
+```
+
+**Usage in Components:**
+```typescript
+import { useThemeStore } from "../stores/ThemeStore";
+
+const MyComponent = () => {
+  const { theme } = useThemeStore();
+  return <View style={{ backgroundColor: theme.primeBg }} />;
+};
+```
+
+**Theme Switching:**
+```typescript
+const { setTheme } = useThemeStore();
+setTheme("defaultDark"); // or "defaultLight"
+```
+
+**Note:** `shadowColor` only works on iOS. Android uses `elevation` with system-defined shadow colors.
+
+### Base Components (CardBase & ModalBase)
+
+Reusable base components for cards and modals with consistent styling.
+
+**CardBase** - Card structure with header, content, and optional footer:
+```typescript
+<CardBase
+  title="Title"
+  subtitle="Optional subtitle"
+  footer={{ label: "Button", onPress: () => {} }}
+  // Styling props (all optional):
+  headerPadding={4}           // p-{n}, default: px-3 py-2
+  contentPadding={4}          // p-{n}, default: px-3 py-2
+  headerTextSize="text-lg"    // "text-sm" | "text-base" | "text-lg" | "text-xl"
+  borderWidth={2}             // outer border, default: 2
+  headerBorderWidth={3}       // header bottom border, default: borderWidth
+  contentBg={theme.primeBg}   // content background color, default: theme.secondaryBg
+  scrollable={true}           // wrap content in ScrollView
+  maxContentHeight={400}      // for scrollable content
+>
+  {children}
+</CardBase>
+```
+
+**ModalBase** - Modal with backdrop using CardBase internally:
+```typescript
+<ModalBase
+  visible={isVisible}
+  onClose={() => setVisible(false)}
+  title="Modal Title"
+  subtitle="Optional"
+  footer={{ label: "Close", onPress: onClose }}
+  scrollable={true}
+  maxContentHeight={400}
+>
+  {children}
+</ModalBase>
+```
+
+ModalBase provides: transparent Modal + backdrop (click-outside-to-close) + Android back button support.
+
+**ModalBase Architecture Note:** Uses absolute-positioned backdrop behind the card content (not nested Pressables). This approach:
+- Fixes modal stacking issues on web (React Native Web renders modals as DOM portals)
+- Allows proper scrolling on Android (no touch event conflicts)
+- Card naturally blocks touches from reaching backdrop due to z-order
+
+**Component Hierarchy:**
+```
+CardBase
+├── ModalBase (uses CardBase)
+│   ├── DeleteEventModal
+│   └── EventOverlay (in calendar.tsx)
+└── EventCardBase (uses CardBase)
+    ├── EventCard
+    └── ProposedEventCard
+```
 
 ### Backend Architecture (apps/server)
 
 ```
 src/
 ├── app.ts                    # Entry point, DI setup, Express config
-├── controllers/              # Request handlers
+├── controllers/              # Request handlers + middleware (per architecture diagram)
-│   ├── AuthController.ts     # login(), register(), refresh(), logout()
+│   ├── AuthController.ts     # login(), register()
-│   ├── ChatController.ts     # sendMessage(), confirmEvent(), rejectEvent(), getConversations(), getConversation()
+│   ├── ChatController.ts     # sendMessage(), confirmEvent() + CalDAV push, rejectEvent(), getConversations(), getConversation(), updateProposalEvent()
-│   └── EventController.ts    # create(), getById(), getAll(), getByDateRange(), update(), delete()
+│   ├── EventController.ts    # create(), getById(), getAll(), getByDateRange(), update(), delete() - pushes/deletes to CalDAV on mutations
-├── middleware/
+│   ├── CaldavController.ts   # saveConfig(), loadConfig(), deleteConfig(), pullEvents(), pushEvents(), pushEvent()
-│   └── AuthMiddleware.ts     # authenticate() - JWT validation
+│   ├── AuthMiddleware.ts     # authenticate() - X-User-Id header validation
+│   └── LoggingMiddleware.ts  # httpLogger - pino-http request logging
+├── logging/
+│   ├── index.ts              # Re-exports
+│   ├── logger.ts             # pino config with redact for sensitive data
+│   └── Logged.ts             # @Logged() class decorator for automatic method logging
 ├── routes/                   # API endpoint definitions
 │   ├── index.ts              # Combines all routes under /api
 │   ├── auth.routes.ts        # /api/auth/*
 │   ├── chat.routes.ts        # /api/chat/* (protected)
-│   └── event.routes.ts       # /api/events/* (protected)
+│   ├── event.routes.ts       # /api/events/* (protected)
+│   └── caldav.routes.ts      # /api/caldav/* (protected)
 ├── services/                 # Business logic
 │   ├── interfaces/           # DB-agnostic interfaces (for dependency injection)
 │   │   ├── AIProvider.ts     # processMessage()
-│   │   ├── UserRepository.ts # + CreateUserData (server-internal DTO)
+│   │   ├── UserRepository.ts # findById, findByEmail, findByUserName, create + CreateUserData
 │   │   ├── EventRepository.ts
-│   │   └── ChatRepository.ts
+│   │   ├── ChatRepository.ts
+│   │   └── CaldavRepository.ts
 │   ├── AuthService.ts
 │   ├── ChatService.ts
-│   └── EventService.ts
+│   ├── EventService.ts
+│   └── CaldavService.ts      # connect(), pullEvents(), pushEvent(), pushAll(), deleteEvent(), sync logic
 ├── repositories/             # Data access (DB-specific implementations)
 │   ├── index.ts              # Re-exports from ./mongo
 │   └── mongo/                # MongoDB implementation
@@ -130,54 +279,65 @@ src/
 │       │   ├── types.ts      # Shared types (IdVirtual interface)
 │       │   ├── UserModel.ts
 │       │   ├── EventModel.ts
-│       │   └── ChatModel.ts
+│       │   ├── ChatModel.ts
-│       ├── MongoUserRepository.ts
+│       │   └── CaldavConfigModel.ts
+│       ├── MongoUserRepository.ts  # findById, findByEmail, findByUserName, create
 │       ├── MongoEventRepository.ts
-│       └── MongoChatRepository.ts
+│       ├── MongoChatRepository.ts
+│       └── MongoCaldavRepository.ts
 ├── ai/
 │   ├── GPTAdapter.ts         # Implements AIProvider using OpenAI GPT
 │   ├── index.ts              # Re-exports GPTAdapter
 │   └── utils/                # Shared AI utilities (provider-agnostic)
 │       ├── index.ts          # Re-exports
-│       ├── eventFormatter.ts # formatExistingEvents() for system prompt
+│       ├── eventFormatter.ts # Re-exports formatDate/Time/DateTime from shared
 │       ├── systemPrompt.ts   # buildSystemPrompt() - German calendar assistant prompt
 │       ├── toolDefinitions.ts # TOOL_DEFINITIONS - provider-agnostic tool specs
-│       └── toolExecutor.ts   # executeToolCall() - handles getDay, proposeCreate/Update/Delete, searchEvents
+│       └── toolExecutor.ts   # executeToolCall() - handles getDay, proposeCreate/Update/Delete, searchEvents, getEventsInRange
-└── utils/
+├── utils/
-    ├── jwt.ts                # signToken(), verifyToken()
+│   ├── password.ts           # hash(), compare() using bcrypt
-    ├── password.ts           # hash(), compare()
+│   ├── eventFormatters.ts    # getWeeksOverview(), getMonthOverview() - formatted event listings
-    ├── eventFormatters.ts    # getWeeksOverview(), getMonthOverview() - formatted event listings
+│   └── recurrenceExpander.ts # expandRecurringEvents() - expand recurring events into occurrences
-    └── recurrenceExpander.ts # expandRecurringEvents() - expand recurring events into occurrences
+└── scripts/
+    └── hash-password.js      # Utility to hash passwords for manual DB updates
 ```
 
 **API Endpoints:**
 - `POST /api/auth/login` - User login
 - `POST /api/auth/register` - User registration
-- `POST /api/auth/refresh` - Refresh JWT token
-- `POST /api/auth/logout` - User logout
 - `GET /api/events` - Get all events (protected)
 - `GET /api/events/range` - Get events by date range (protected)
 - `GET /api/events/:id` - Get single event (protected)
 - `POST /api/events` - Create event (protected)
 - `PUT /api/events/:id` - Update event (protected)
-- `DELETE /api/events/:id` - Delete event (protected)
+- `DELETE /api/events/:id` - Delete event (protected, query params: mode, occurrenceDate for recurring)
 - `POST /api/chat/message` - Send message to AI (protected)
 - `POST /api/chat/confirm/:conversationId/:messageId` - Confirm proposed event (protected)
 - `POST /api/chat/reject/:conversationId/:messageId` - Reject proposed event (protected)
 - `GET /api/chat/conversations` - Get all conversations (protected)
 - `GET /api/chat/conversations/:id` - Get messages of a conversation with cursor-based pagination (protected)
+- `PUT /api/chat/messages/:messageId/proposal` - Update proposal event data before confirming (protected)
+- `PUT /api/caldav/config` - Save CalDAV config (protected)
+- `GET /api/caldav/config` - Load CalDAV config (protected)
+- `DELETE /api/caldav/config` - Delete CalDAV config (protected)
+- `POST /api/caldav/pull` - Pull events from CalDAV server (protected)
+- `POST /api/caldav/pushAll` - Push all unsynced events (protected)
+- `POST /api/caldav/push/:caldavUUID` - Push single event (protected)
 - `GET /health` - Health check
 - `POST /api/ai/test` - AI test endpoint (development only)
 
 ### Shared Package (packages/shared)
 
+The shared package is compiled to `dist/` (CommonJS). All imports must use `@calchat/shared` (NOT `@calchat/shared/src/...`). Server `dev` and `build` scripts automatically build shared first.
+
 ```
 src/
 ├── index.ts
 ├── models/
 │   ├── index.ts
 │   ├── User.ts           # User, CreateUserDTO, LoginDTO, AuthResponse
-│   ├── CalendarEvent.ts  # CalendarEvent, CreateEventDTO, UpdateEventDTO, ExpandedEvent
+│   ├── CalendarEvent.ts  # CalendarEvent, CreateEventDTO, UpdateEventDTO, ExpandedEvent, CaldavSyncStatus
+│   ├── CaldavConfig.ts   # CaldavConfig
 │   ├── ChatMessage.ts    # ChatMessage, Conversation, SendMessageDTO, CreateMessageDTO,
 │   │                     # GetMessagesOptions, ChatResponse, ConversationSummary,
 │   │                     # ProposedEventChange, EventAction, RespondedAction, UpdateMessageDTO
@@ -185,24 +345,100 @@ src/
 │                         # DAY_TO_GERMAN, DAY_TO_GERMAN_SHORT, MONTH_TO_GERMAN
 └── utils/
     ├── index.ts
-    └── dateHelpers.ts    # getDay() - get date for specific weekday relative to today
+    ├── dateHelpers.ts    # getDay() - get date for specific weekday relative to today
+    ├── formatters.ts     # formatDate(), formatTime(), formatDateTime(), formatDateWithWeekday() - German locale
+    └── rruleHelpers.ts   # parseRRule(), buildRRule(), formatRecurrenceRule() - RRULE parsing, building, and German formatting
 ```
 
 **Key Types:**
-- `User`: id, email, displayName, passwordHash?, createdAt?, updatedAt?
+- `User`: id, email, userName, passwordHash?, createdAt?, updatedAt?
-- `CalendarEvent`: id, userId, title, description?, startTime, endTime, note?, isRecurring?, recurrenceRule?
+- `CalendarEvent`: id, userId, caldavUUID?, etag?, title, description?, startTime, endTime, note?, recurrenceRule?, exceptionDates?, caldavSyncStatus?
+- `CaldavConfig`: userId, serverUrl, username, password, syncIntervalSeconds?
+- `CaldavSyncStatus`: 'synced' | 'error'
 - `ExpandedEvent`: Extends CalendarEvent with occurrenceStart, occurrenceEnd (for recurring event instances)
-- `ChatMessage`: id, conversationId, sender ('user' | 'assistant'), content, proposedChange?, respondedAction?
+- `ChatMessage`: id, conversationId, sender ('user' | 'assistant'), content, proposedChanges?
-- `ProposedEventChange`: action ('create' | 'update' | 'delete'), eventId?, event?, updates?
+- `ProposedEventChange`: id, action ('create' | 'update' | 'delete'), eventId?, event?, updates?, respondedAction?, deleteMode?, occurrenceDate?, conflictingEvents?
+  - Each proposal has unique `id` (e.g., "proposal-0") for individual confirm/reject
+  - `respondedAction` tracks user response per proposal (not per message)
+  - `deleteMode` ('single' | 'future' | 'all') and `occurrenceDate` for recurring event deletion
+  - `conflictingEvents` contains events that overlap with the proposed time (for conflict warnings)
+- `ConflictingEvent`: title, startTime, endTime - simplified event info for conflict display
+- `RecurringDeleteMode`: 'single' | 'future' | 'all' - delete modes for recurring events
+- `DeleteRecurringEventDTO`: mode, occurrenceDate? - DTO for recurring event deletion
 - `Conversation`: id, userId, createdAt?, updatedAt? (messages loaded separately via lazy loading)
-- `CreateEventDTO`: Used for creating events AND for AI-proposed events
+- `CreateUserDTO`: email, userName, password (for registration)
+- `LoginDTO`: identifier (email OR userName), password
+- `CreateEventDTO`: Used for creating events AND for AI-proposed events, includes optional `exceptionDates` for proposals
 - `GetMessagesOptions`: Cursor-based pagination with `before?: string` and `limit?: number`
 - `ConversationSummary`: id, lastMessage?, createdAt? (for conversation list)
-- `UpdateMessageDTO`: respondedAction? (for marking messages as confirmed/rejected)
+- `UpdateMessageDTO`: proposalId?, respondedAction? (for marking individual proposals as confirmed/rejected)
 - `RespondedAction`: 'confirm' | 'reject' (tracks user response to proposed events)
 - `Day`: "Monday" | "Tuesday" | ... | "Sunday"
 - `Month`: "January" | "February" | ... | "December"
 
+### AI Context Architecture
+
+The AI assistant fetches calendar data on-demand rather than receiving pre-loaded events. This reduces token usage significantly.
+
+**AIContext Interface:**
+```typescript
+interface AIContext {
+  userId: string;
+  conversationHistory: ChatMessage[];  // Last 20 messages for context
+  currentDate: Date;
+  // Callbacks for on-demand data fetching:
+  fetchEventsInRange: (start: Date, end: Date) => Promise<ExpandedEvent[]>;
+  searchEvents: (query: string) => Promise<CalendarEvent[]>;
+  fetchEventById: (eventId: string) => Promise<CalendarEvent | null>;
+}
+```
+
+**Available AI Tools:**
+- `getDay` - Calculate relative dates (e.g., "next Friday")
+- `getCurrentDateTime` - Get current timestamp
+- `proposeCreateEvent` - Propose new event (includes automatic conflict detection)
+- `proposeUpdateEvent` - Propose event modification
+- `proposeDeleteEvent` - Propose event deletion (supports recurring delete modes)
+- `searchEvents` - Search events by title (returns IDs for update/delete)
+- `getEventsInRange` - Load events for a date range (for "what's today?" queries)
+
+**Conflict Detection:**
+When creating events, `toolExecutor` automatically:
+1. Fetches events for the target day via `fetchEventsInRange`
+2. Checks for time overlaps using `occurrenceStart/occurrenceEnd` (important for recurring events)
+3. Returns `conflictingEvents` array in the proposal for UI display
+4. Adds ⚠️ warning to tool result so AI can inform user
+
+### CalDAV Synchronization
+
+CalDAV sync with external calendar servers (e.g., Radicale) using `tsdav` and `ical.js`.
+
+**Naming Convention:** All CalDAV-related identifiers use `Caldav` (PascalCase) / `caldav` (camelCase), NOT `CalDav`. The only exception is the protocol name "CalDAV" in comments and log messages.
+
+**Sync Triggers (client-side via `CaldavConfigService.sync()`):**
+- **Login** (`login.tsx`): After successful authentication
+- **Auto-login** (`AuthGuard.tsx`): After `loadStoredUser()` if authenticated
+- **Calendar timer** (`calendar.tsx`): Events load instantly from DB on focus (`loadEvents`), CalDAV sync runs in background (`syncAndReload`) and reloads events after. Repeats every 10s via `setInterval`
+- **Sync button** (`settings.tsx`): Manual trigger in CaldavSettings
+
+**Lazy sync (server-side in ChatService):**
+- AI data access callbacks (`fetchEventsInRange`, `searchEvents`, `fetchEventById`) trigger `syncOnce()` before the first DB query
+- Uses `CaldavService.sync()` which checks config internally (silent no-op without config)
+
+**Single-event sync (server-side in controllers):**
+- `EventController`: `pushToCaldav()` after create/update, `deleteFromCaldav()` after delete
+- `ChatController`: `pushAll()` after confirming an event proposal
+
+**Sync Flow:**
+1. `sync()` calls `pushAll` (push unsynced local events) then `pull` (fetch remote events)
+2. `pullEvents`: Compares etags to skip unchanged events, creates/updates local events, deletes locally if removed remotely
+3. `pushEvent`: Creates or updates remote event, fetches new etag after push
+
+**Architecture:**
+- `CaldavService` depends on `CaldavRepository` (config storage) and `EventService` (event CRUD)
+- `ChatService` depends on `EventService` and `CaldavService` (lazy CalDAV sync on AI data access)
+- `EventController` and `ChatController` both receive `CaldavService` for CalDAV push on mutations
+
 ### Database Abstraction
 
 The repository pattern allows swapping databases:
@@ -239,6 +475,39 @@ const Schema = new Schema<Doc, Model<Doc, {}, {}, IdVirtual>, {}, {}, IdVirtual>
 
 Repositories use `doc.toJSON() as unknown as Type` casting (required because Mongoose's TypeScript types don't reflect virtual fields in toJSON output).
 
+### Logging
+
+Structured logging with pino (server) and react-native-logs (client).
+
+**Server Logging:**
+- `pino` with `pino-pretty` for development, JSON in production
+- `pino-http` middleware logs all HTTP requests (method, path, status, duration)
+- `@Logged()` class decorator for automatic method logging on repositories and services
+- Sensitive data (password, token, etc.) automatically redacted via pino's `redact` config
+
+**@Logged Decorator Pattern:**
+```typescript
+@Logged("MongoEventRepository")
+export class MongoEventRepository implements EventRepository { ... }
+
+@Logged("GPTAdapter")
+export class GPTAdapter implements AIProvider { ... }
+```
+
+The decorator uses a Proxy to intercept method calls lazily, preserves sync/async nature, and logs start/completion/failure with duration.
+
+**Log Summarization:**
+The `@Logged` decorator automatically summarizes large arguments to keep logs readable:
+- `conversationHistory` → `"[5 messages]"`
+- `proposedChanges` → logged in full (for debugging AI issues)
+- Long strings (>100 chars) → truncated
+- Arrays → `"[Array(n)]"`
+
+**Client Logging:**
+- `react-native-logs` with namespaced loggers (apiLogger, storeLogger)
+- ApiClient logs all requests with method, endpoint, status, duration
+- Log level: debug in __DEV__, warn in production
+
 ## MVP Feature Scope
 
 ### Must-Have
@@ -253,7 +522,7 @@ Repositories use `doc.toJSON() as unknown as Type` casting (required because Mon
 ### Nice-to-Have
 - iCalendar import/export
 - Multiple calendars
-- CalDAV synchronization with external services
+- ~~CalDAV synchronization with external services~~ (implemented)
 
 ## Development Environment
 
@@ -266,14 +535,29 @@ docker compose down                   # Stop services
 - MongoDB: `localhost:27017` (root/mongoose)
 - Mongo Express UI: `localhost:8083` (admin/admin)
 
+### Radicale CalDAV Server (Docker)
+```bash
+cd apps/server/docker/radicale
+docker compose up -d                  # Start Radicale CalDAV server
+```
+- Radicale: `localhost:5232`
+
+### Server Docker Image
+```bash
+# Build (requires local build context):
+docker build -f apps/server/docker/Dockerfile -t calchat-server .
+docker run -p 3001:3001 --env-file apps/server/.env calchat-server
+```
+Multi-stage COPY-based build: copies `package.json` files first for layer caching, then source code. Compiles shared + server, then copies only `dist/` and production dependencies to the runtime stage. Exposes port 3001. In CI, the `plugins/docker` Drone plugin builds and pushes the image automatically.
+
 ### Environment Variables
 Server requires `.env` file in `apps/server/`:
 ```
-JWT_SECRET=your-secret-key
-JWT_EXPIRES_IN=1h
 MONGODB_URI=mongodb://root:mongoose@localhost:27017/calchat?authSource=admin
 OPENAI_API_KEY=sk-proj-...
 USE_TEST_RESPONSES=false    # true = static test responses, false = real GPT AI
+LOG_LEVEL=debug             # debug | info | warn | error | fatal
+NODE_ENV=development        # development = pretty logs, production = JSON
 ```
 
 ## Current Implementation Status
@@ -281,33 +565,67 @@ USE_TEST_RESPONSES=false    # true = static test responses, false = real GPT AI
 **Backend:**
 - **Implemented:**
   - `AuthController`: login(), register() with error handling
-  - `AuthService`: login(), register() with password validation
+  - `AuthService`: login() supports email OR userName, register() checks for existing email AND userName
-  - `MongoUserRepository`: findByEmail(), create()
+  - `AuthMiddleware`: Validates X-User-Id header for protected routes
+  - `MongoUserRepository`: findById(), findByEmail(), findByUserName(), create()
   - `utils/password`: hash(), compare() using bcrypt
-  - `utils/jwt`: signToken() (verifyToken() pending)
+  - `scripts/hash-password.js`: Utility for manual password resets
   - `dotenv` integration for environment variables
   - `ChatController`: sendMessage(), confirmEvent(), rejectEvent()
   - `ChatService`: processMessage() with test responses (create, update, delete actions), confirmEvent() handles all CRUD actions
-  - `MongoEventRepository`: Full CRUD implemented (findById, findByUserId, findByDateRange, create, update, delete)
+  - `MongoEventRepository`: Full CRUD implemented (findById, findByUserId, findByDateRange, create, update, delete, addExceptionDate)
   - `EventController`: Full CRUD (create, getById, getAll, getByDateRange, update, delete)
-  - `EventService`: Full CRUD with recurring event expansion via recurrenceExpander
+  - `EventService`: Full CRUD with recurring event expansion via recurrenceExpander, deleteRecurring() with three modes (single/future/all)
   - `utils/eventFormatters`: getWeeksOverview(), getMonthOverview() with German localization
   - `utils/recurrenceExpander`: expandRecurringEvents() using rrule library for RRULE parsing
   - `ChatController`: getConversations(), getConversation() with cursor-based pagination support
   - `ChatService`: getConversations(), getConversation(), processMessage() uses real AI or test responses (via USE_TEST_RESPONSES), confirmEvent()/rejectEvent() update respondedAction and persist response messages
-  - `MongoChatRepository`: Full CRUD implemented (getConversationsByUser, createConversation, getMessages with cursor pagination, createMessage, updateMessage)
+  - `MongoChatRepository`: Full CRUD implemented (getConversationsByUser, createConversation, getMessages with cursor pagination, createMessage, updateMessage, updateProposalResponse, updateProposalEvent)
-  - `ChatRepository` interface: updateMessage() added for respondedAction tracking
+  - `ChatRepository` interface: updateMessage(), updateProposalResponse(), updateProposalEvent() for per-proposal tracking
-  - `GPTAdapter`: Full implementation with OpenAI GPT (gpt-5-mini model), function calling for calendar operations
+  - `GPTAdapter`: Full implementation with OpenAI GPT (gpt-4o-mini model), function calling for calendar operations, collects multiple proposals per response
-  - `ai/utils/`: Provider-agnostic shared utilities (systemPrompt, toolDefinitions, toolExecutor, eventFormatter)
+  - `ai/utils/`: Provider-agnostic shared utilities (systemPrompt, toolDefinitions, toolExecutor)
-- **Stubbed (TODO):**
+  - `ai/utils/systemPrompt`: AI fetches events on-demand (no pre-loaded context), includes RRULE documentation, warns AI not to put RRULE in description field, instructs AI not to show event IDs to users
-  - `AuthMiddleware.authenticate()`: Currently uses fake user for testing
+  - `ai/utils/toolDefinitions`: proposeUpdateEvent supports `recurrenceRule` parameter, getEventsInRange tool for on-demand event loading
-  - `AuthController`: refresh(), logout()
+  - `ai/utils/toolExecutor`: Async execution, conflict detection uses `occurrenceStart/occurrenceEnd` for recurring events, returns `conflictingEvents` in proposals
-  - `AuthService`: refreshToken()
+  - `MongoEventRepository`: Includes `searchByTitle()` for case-insensitive title search
+  - `utils/recurrenceExpander`: Handles RRULE parsing, strips `RRULE:` prefix if present (AI may include it), filters out exceptionDates
+  - `logging/`: Structured logging with pino, pino-http middleware, @Logged decorator
+  - All repositories and GPTAdapter decorated with @Logged for automatic method logging
+  - `CaldavService`: Full CalDAV sync (connect, pullEvents, pushEvent, pushAll, deleteEvent, sync, getConfig, saveConfig, deleteConfig). `sync()` checks config internally and is a silent no-op without config.
+  - `CaldavController`: REST endpoints for config CRUD, pull, push
+  - `MongoCaldavRepository`: Config persistence with createOrUpdate, findByUserId, deleteByUserId
+  - `EventController`: CalDAV push on create/update, CalDAV delete on delete (via pushToCaldav/deleteFromCaldav helpers)
+  - `ChatController`: CalDAV pushAll after confirmEvent (ensures chat-created events sync)
+  - `ChatService`: Uses EventService + CaldavService (lazy sync on AI data access via syncOnce pattern)
+  - `EventService`: Extended with searchByTitle(), findByCaldavUUID()
+  - `utils/eventFormatters`: Refactored to use EventService instead of EventRepository
+  - CORS configured to allow X-User-Id header
 
-**Shared:** Types, DTOs, constants (Day, Month with German translations), ExpandedEvent type, and date utilities defined and exported.
+**Shared:**
+- Types, DTOs, constants (Day, Month with German translations), ExpandedEvent type, CaldavConfig, CaldavSyncStatus defined and exported
+- `rruleHelpers.ts`: `parseRRule()` parses RRULE strings using rrule library, returns `ParsedRRule` with freq, until, count, interval, byDay. `buildRRule()` builds RRULE from RepeatType + interval. `formatRecurrenceRule()` formats RRULE into German description (e.g., "Jede Woche", "Alle 2 Monate"). Exports `REPEAT_TYPE_LABELS` and `RepeatType`.
+- `formatters.ts`: German date/time formatters (`formatDate`, `formatTime`, `formatDateTime`, `formatDateWithWeekday`, `formatDateKey`) used by both client and server
+- rrule library added as dependency for RRULE parsing
 
 **Frontend:**
-- Tab navigation (Chat, Calendar) implemented with basic UI
+- **Authentication fully implemented:**
+  - `AuthStore`: Manages user state with expo-secure-store (native) / localStorage (web)
+  - `AuthService`: login(), register(), logout() - calls backend API
+  - `ApiClient`: Automatically injects X-User-Id header for authenticated requests, handles empty responses (204)
+  - `AuthGuard`: Reusable component that wraps protected routes - loads user, preloads app data (events + CalDAV config) into stores before dismissing spinner, triggers CalDAV sync, shows loading, redirects if unauthenticated. Exports `preloadAppData()` (also called by `login.tsx`)
+  - Login screen: Supports email OR userName login, uses CustomTextInput with focus border, preloads app data + triggers CalDAV sync after successful login
+  - Register screen: Email validation, checks for existing email/userName, uses CustomTextInput with focus border
+  - `AuthButton`: Reusable button component with themed shadow
+  - `Header`: Themed header component (logout moved to Settings)
+  - `(tabs)/_layout.tsx`: Wraps tabs with AuthGuard for protected access
+  - `index.tsx`: Simple redirect to chat (AuthGuard handles auth)
+- **Theme system fully implemented:**
+  - `ThemeStore`: Zustand store with theme state and setTheme()
+  - `Themes.tsx`: THEMES object with defaultLight/defaultDark variants
+  - All components use `useThemeStore()` for reactive theme colors
+  - Settings screen with theme switcher (light/dark) and CalDAV configuration (url, username, password with save/sync buttons, loads existing config on mount). Save/Sync buttons show independent feedback via `FeedbackRow` component: spinner + loading text during request, then success (green) or error (red) message that auto-clears after 3s. Both feedbacks can be visible simultaneously.
+  - `BaseButton`: Reusable themed button component
+- Tab navigation (Chat, Calendar, Settings) implemented with themed UI
 - Calendar screen fully functional:
   - Month navigation with grid display and Ionicons (chevron-back/forward)
   - MonthSelector dropdown with infinite scroll (dynamically loads months, lazy-loaded when modal opens, cleared on close for memory efficiency)
@@ -315,25 +633,91 @@ USE_TEST_RESPONSES=false    # true = static test responses, false = real GPT AI
   - Orange dot indicator for days with events
   - Tap-to-open modal overlay showing EventCards for selected day
   - Supports events from adjacent months visible in grid
-  - Uses `useFocusEffect` for automatic reload on tab focus
+  - Events load instantly from local DB on tab focus, CalDAV sync runs non-blocking in background (`syncAndReload`) with 10s interval
+  - DeleteEventModal integration for recurring event deletion with three modes
+  - EventOverlay hides when DeleteEventModal is open (fixes modal stacking on web)
 - Chat screen fully functional with FlashList, message sending, and event confirm/reject
-  - Messages persisted to database via ChatService and loaded on mount
+  - **Multiple event proposals**: AI can propose multiple events in one response
+  - Arrow navigation between proposals with "Event X von Y" counter
+  - Each proposal individually confirmable/rejectable
+  - **Typing indicator**: Animated dots (. .. ...) shown after 500ms delay while waiting for AI response
+  - Messages persisted to database via ChatService, loaded via `useFocusEffect` when screen gains focus
   - Tracks conversationId for message continuity across sessions
   - ChatStore with addMessages() for bulk loading, chatMessageToMessageData() helper
   - KeyboardAvoidingView for proper keyboard handling (iOS padding, Android height)
-  - Auto-scroll to end on new messages and keyboard show
+  - Auto-scroll to end on new messages and keyboard show; initial load uses `onContentSizeChange` with `animated: false` to start at bottom without visible scrolling
   - keyboardDismissMode="interactive" and keyboardShouldPersistTaps="handled"
-- `ApiClient`: get(), post(), put(), delete() implemented
+- `EventService`: getAll(), getById(), getByDateRange(), create(), update(), delete(mode, occurrenceDate) - fully implemented with recurring delete modes
-- `EventService`: getAll(), getById(), getByDateRange(), create(), update(), delete() - fully implemented
+- `ChatService`: sendMessage(), confirmEvent(deleteMode, occurrenceDate), rejectEvent(), getConversations(), getConversation(), updateProposalEvent() - fully implemented with cursor pagination, recurring delete support, and proposal editing
-- `ChatService`: sendMessage(), confirmEvent(), rejectEvent(), getConversations(), getConversation() - fully implemented with cursor pagination
+- `CaldavConfigService`: saveConfig(), getConfig(), deleteConfig(), pull(), pushAll(), sync() - CalDAV config management and sync trigger
-- `EventCardBase`: Shared base component with event layout (header, date/time/recurring icons, description) - used by both EventCard and ProposedEventCard
+- `CustomTextInput`: Themed text input with focus border highlight. Props: `text`, `onValueChange`, `placeholder`, `placeholderTextColor`, `secureTextEntry`, `autoCapitalize`, `keyboardType`, `className`, `multiline`. No default padding — callers must set padding via `className` (e.g., `px-3 py-2` or `p-4`). When not focused, cursor is reset to start (`selection={{ start: 0 }}`) to avoid text appearing scrolled to the end.
-- `EventCard`: Uses EventCardBase + edit/delete buttons for calendar display
+- `CardBase`: Reusable card component with header (title/subtitle), content area, and optional footer button - configurable padding, border, text size via props, ScrollView uses `nestedScrollEnabled` for Android
-- `ProposedEventCard`: Uses EventCardBase + confirm/reject buttons for chat proposals (supports create/update/delete actions)
+- `ModalBase`: Reusable modal wrapper with backdrop (absolute-positioned behind card), uses CardBase internally - provides click-outside-to-close, Android back button support, and proper scrolling on Android
-- `Themes.tsx`: Centralized color definitions including textPrimary, borderPrimary, eventIndicator, secondaryBg
+- `EventCardBase`: Event card with date/time/recurring icons - uses CardBase for structure. Accepts `recurrenceRule` string (not boolean) and displays German-formatted recurrence via `formatRecurrenceRule()`
-- `EventsStore`: Zustand store with setEvents(), addEvent(), updateEvent(), deleteEvent() - stores ExpandedEvent[]
+- `EventCard`: Uses EventCardBase + edit/delete buttons (TouchableOpacity with delayPressIn for scroll-friendly touch handling)
-- `ChatStore`: Zustand store with addMessage(), addMessages(), updateMessage(), clearMessages() - loads from server on mount and persists across tab switches
+- `ProposedEventCard`: Uses EventCardBase + confirm/reject/edit buttons for chat proposals, displays green highlighted text for new changes ("Neue Ausnahme: [date]" for single delete, "Neues Ende: [date]" for UNTIL updates), shows yellow conflict warnings when proposed time overlaps with existing events. Edit button allows modifying proposals before confirming.
-- Auth screens (Login, Register), Event Detail, and Note screens exist as skeletons
+- `DeleteEventModal`: Delete confirmation modal using ModalBase - shows three options for recurring events (single/future/all), simple confirm for non-recurring
-- AuthStore defined with `throw new Error('Not implemented')`
+- `CalendarToolbar` (in calendar.tsx): Toolbar between header and weekdays with Sync button (CalDAV sync with spinner/green checkmark/red X feedback, disabled without config) and Logout button
+- `EventOverlay` (in calendar.tsx): Day events overlay using ModalBase - shows EventCards for selected day
+- `Themes.tsx`: Theme definitions with THEMES object (defaultLight, defaultDark) including all color tokens (textPrimary, borderPrimary, eventIndicator, secondaryBg, shadowColor, etc.)
+- `EventsStore`: Zustand store with setEvents(), addEvent(), updateEvent(), deleteEvent() - stores ExpandedEvent[], preloaded by AuthGuard
+- `CaldavConfigStore`: Zustand store with config (CaldavConfig | null), setConfig() - cached CalDAV config, preloaded by AuthGuard, used by Settings to avoid API call on mount
+- `ChatStore`: Zustand store with addMessage(), addMessages(), updateMessage(), clearMessages(), isWaitingForResponse/setWaitingForResponse() for typing indicator - loads from server on mount and persists across tab switches
+- `ThemeStore`: Zustand store with theme/setTheme() for reactive theme switching across all components
+- `ChatBubble`: Reusable chat bubble component with Tailwind styling, used by ChatMessage and TypingIndicator
+- `TypingIndicator`: Animated typing indicator component showing `. → .. → ...` loop while waiting for AI response
+- Event Detail and Note screens exist as skeletons
+- `editEvent.tsx`: Dual-mode event editor screen
+  - **Calendar mode**: Edit existing events, create new events - calls EventService API
+  - **Chat mode**: Edit AI-proposed events before confirming - updates ChatStore locally and persists to server via ChatService.updateProposalEvent()
+  - Route params: `mode` ('calendar' | 'chat'), `id?`, `date?`, `eventData?` (JSON), `proposalContext?` (JSON with messageId, proposalId, conversationId)
+  - Supports recurring events with RRULE configuration (daily/weekly/monthly/yearly)
+
+## Building
+
+### Local APK Build with EAS
+```bash
+npm run build:apk -w @calchat/client
+```
+
+This uses the `preview` profile from `eas.json` which builds an APK with:
+- `arm64-v8a` architecture only (smaller APK size)
+- No credentials required (`withoutCredentials: true`)
+- Internal distribution
+
+**Requirements:** Android SDK and Java must be installed locally.
+
+**EAS Configuration:** `apps/client/eas.json` contains build profiles:
+- `development`: Development client with internal distribution
+- `preview`: APK build for testing (used by `build:apk`)
+- `production`: Production build with auto-increment versioning
+
+**App Identity:**
+- Package name: `com.gilmour109.calchat`
+- EAS Project ID: `b722dde6-7d89-48ff-9095-e007e7c7da87`
+
+## CI/CD (Drone)
+
+The project uses Drone CI (`.drone.yml`) with five pipelines:
+
+**On push to main:**
+1. **`server_build_and_test`**: Builds the server (`npm ci` + `npm run build`) and runs Jest tests (`npm run test`)
+2. **`check_for_formatting`**: Checks Prettier formatting across all workspaces (`npm run check_format`)
+3. **`deploy_latest`**: Builds Docker image, pushes to Gitea Container Registry (`gitea.gilmour109.de/gilmour109/calchat-server:latest`), then SSHs into VPS (`10.0.0.1`) to pull and restart via `docker compose`. Depends on both pipelines above passing first.
+
+**On tag:**
+4. **`upload_tag`**: Builds Docker image tagged with the git tag (`${DRONE_TAG}`), pushes to registry, then deploys to k3s cluster (`192.168.178.201`) via SSH using `envsubst` with a Kubernetes manifest template.
+
+**On promote:**
+5. **`upload_commit`**: Builds Docker image tagged with short commit SHA (first 8 chars), pushes to registry, then deploys to k3s cluster (`192.168.178.201`) via SSH using `envsubst` with a Kubernetes manifest template.
+
+## Testing
+
+Server uses Jest with ts-jest for unit testing. Config in `apps/server/jest.config.js` ignores `/node_modules/` and `/dist/`.
+
+**Existing tests:**
+- `src/utils/password.test.ts` - Tests for bcrypt hash() and compare()
+- `src/utils/recurrenceExpander.test.ts` - Tests for expandRecurringEvents() (non-recurring, weekly/daily/UNTIL recurrence, EXDATE filtering, RRULE: prefix stripping, invalid RRULE fallback, multi-day events, sorting)
 
 ## Documentation
 

README.md

@@ -1,50 +1,141 @@
-# Welcome to your Expo app 👋
+# CalChat
 
-This is an [Expo](https://expo.dev) project created with [`create-expo-app`](https://www.npmjs.com/package/create-expo-app).
+Kalender-App mit KI-Chatbot. Termine lassen sich per Chat in natuerlicher Sprache erstellen, bearbeiten und loeschen.
 
-## Get started
+## Tech Stack
 
-1. Install dependencies
+| Bereich | Technologie |
+|---------|-------------|
+| Frontend | React Native, Expo, Expo-Router, NativeWind, Zustand |
+| Backend | Express.js, MongoDB, Mongoose, OpenAI GPT |
+| Shared | TypeScript Monorepo mit npm Workspaces |
+| Optional | CalDAV-Sync (z.B. Radicale) |
 
-   ```bash
+## Voraussetzungen
-   npm install
-   ```
 
-2. Start the app
+- Node.js (>= 20)
+- npm
+- Docker & Docker Compose (fuer MongoDB)
+- OpenAI API Key (fuer KI-Chat)
+- Android SDK + Java (nur fuer APK-Build)
 
-   ```bash
+## Projekt aufsetzen
-   npx expo start
-   ```
 
-In the output, you'll find options to open the app in a
+### 1. Repository klonen
-
-- [development build](https://docs.expo.dev/develop/development-builds/introduction/)
-- [Android emulator](https://docs.expo.dev/workflow/android-studio-emulator/)
-- [iOS simulator](https://docs.expo.dev/workflow/ios-simulator/)
-- [Expo Go](https://expo.dev/go), a limited sandbox for trying out app development with Expo
-
-You can start developing by editing the files inside the **app** directory. This project uses [file-based routing](https://docs.expo.dev/router/introduction).
-
-## Get a fresh project
-
-When you're ready, run:
 
 ```bash
-npm run reset-project
+git clone <repo-url>
+cd calchat
 ```
 
-This command will move the starter code to the **app-example** directory and create a blank **app** directory where you can start developing.
+### 2. Dependencies installieren
 
-## Learn more
+```bash
+npm install
+```
 
-To learn more about developing your project with Expo, look at the following resources:
+Installiert alle Dependencies fuer Client, Server und Shared.
 
-- [Expo documentation](https://docs.expo.dev/): Learn fundamentals, or go into advanced topics with our [guides](https://docs.expo.dev/guides).
+### 3. MongoDB starten
-- [Learn Expo tutorial](https://docs.expo.dev/tutorial/introduction/): Follow a step-by-step tutorial where you'll create a project that runs on Android, iOS, and the web.
 
-## Join the community
+```bash
+cd apps/server/docker/mongo
+docker compose up -d
+```
 
-Join our community of developers creating universal apps.
+- MongoDB: `localhost:27017` (root/mongoose)
+- Mongo Express UI: `localhost:8083` (admin/admin)
 
-- [Expo on GitHub](https://github.com/expo/expo): View our open source platform and contribute.
+### 4. Server konfigurieren
-- [Discord community](https://chat.expo.dev): Chat with Expo users and ask questions.
+
+```bash
+cp apps/server/.env.example apps/server/.env
+```
+
+`apps/server/.env` bearbeiten:
+
+```env
+MONGODB_URI=mongodb://root:mongoose@localhost:27017/calchat?authSource=admin
+OPENAI_API_KEY=sk-proj-...    # Eigenen Key eintragen
+USE_TEST_RESPONSES=false       # true = statische Testantworten ohne GPT
+LOG_LEVEL=debug
+NODE_ENV=development
+PORT=3000
+```
+
+### 5. Client konfigurieren
+
+```bash
+cp apps/client/.env.example apps/client/.env
+```
+
+`apps/client/.env` bearbeiten:
+
+```env
+# Fuer Emulator/Web:
+EXPO_PUBLIC_API_URL=http://localhost:3000/api
+
+# Fuer physisches Geraet im gleichen Netzwerk:
+EXPO_PUBLIC_API_URL=http://<DEINE-LOKALE-IP>:3000/api
+```
+
+### 6. Server starten
+
+```bash
+npm run dev -w @calchat/server
+```
+
+Startet den Server auf Port 3000 (mit `tsx watch` - startet bei Dateiänderungen automatisch neu (oder sollte es zumindest)).
+
+### 7. Client starten
+
+```bash
+npm run start -w @calchat/client
+```
+
+Dann im Expo-Menue die gewuenschte Plattform waehlen:
+- `a` - Android Emulator
+- `i` - iOS Simulator
+- `w` - Web Browser
+
+Oder direkt:
+
+```bash
+npm run android -w @calchat/client
+npm run ios -w @calchat/client
+npm run web -w @calchat/client
+```
+
+## CalDAV (optional)
+
+Fuer CalDAV-Synchronisation kann ein Radicale-Server gestartet werden:
+
+```bash
+cd apps/server/docker/radicale
+docker compose up -d
+```
+
+Radicale ist dann unter `localhost:5232` erreichbar. Die CalDAV-Verbindung wird in der App unter Einstellungen konfiguriert.
+
+## Weitere Befehle
+
+```bash
+npm run format                          # Prettier auf alle TS/TSX-Dateien
+npm run lint -w @calchat/client         # ESLint (Client)
+npm run build -w @calchat/server        # TypeScript kompilieren (Server)
+npm run build:apk -w @calchat/client    # APK lokal bauen (EAS)
+```
+
+## Projektstruktur
+
+```
+calchat/
+├── apps/
+│   ├── client/          # Expo React Native App
+│   └── server/          # Express.js Backend
+│       └── docker/
+│           ├── mongo/   # MongoDB + Mongo Express
+│           └── radicale/ # CalDAV Server
+└── packages/
+    └── shared/          # Geteilte Types und Utilities
+```

apps/client/.env.example

@@ -0,0 +1,8 @@
+# Base URL of the CalChat API server
+# Must include the /api path suffix
+# Use your local network IP for mobile device testing, or localhost for emulator/web
+# Examples:
+#   http://192.168.178.22:3001/api   (local network, for physical device)
+#   http://localhost:3001/api         (emulator or web)
+#   https://calchat.example.com/api   (production)
+EXPO_PUBLIC_API_URL=http://localhost:3001/api

apps/client/app.json

@@ -1,50 +1,38 @@
 {
   "expo": {
     "jsEngine": "hermes",
-    "name": "caldav",
+    "name": "CalChat",
     "slug": "caldav",
     "version": "1.0.0",
     "orientation": "portrait",
-    "icon": "./assets/images/icon.png",
+    "scheme": "calchat",
-    "scheme": "caldav",
     "userInterfaceStyle": "automatic",
     "newArchEnabled": true,
     "ios": {
       "supportsTablet": true
     },
     "android": {
-      "adaptiveIcon": {
+      "package": "com.gilmour109.calchat",
-        "backgroundColor": "#E6F4FE",
-        "foregroundImage": "./assets/images/android-icon-foreground.png",
-        "backgroundImage": "./assets/images/android-icon-background.png",
-        "monochromeImage": "./assets/images/android-icon-monochrome.png"
-      },
       "edgeToEdgeEnabled": true,
       "predictiveBackGestureEnabled": false
     },
     "web": {
       "output": "static",
-      "favicon": "./assets/images/favicon.png",
       "bundler": "metro"
     },
     "plugins": [
-      "expo-router",
+      "expo-router"
-      [
-        "expo-splash-screen",
-        {
-          "image": "./assets/images/splash-icon.png",
-          "imageWidth": 200,
-          "resizeMode": "contain",
-          "backgroundColor": "#ffffff",
-          "dark": {
-            "backgroundColor": "#000000"
-          }
-        }
-      ]
     ],
     "experiments": {
       "typedRoutes": true,
       "reactCompiler": true
-    }
+    },
+    "extra": {
+      "router": {},
+      "eas": {
+        "projectId": "b722dde6-7d89-48ff-9095-e007e7c7da87"
+      }
+    },
+    "owner": "gilmour109"
   }
 }

apps/client/eas.json

@@ -0,0 +1,29 @@
+{
+  "cli": {
+    "version": ">= 16.28.0",
+    "appVersionSource": "remote"
+  },
+  "build": {
+    "development": {
+      "developmentClient": true,
+      "distribution": "internal"
+    },
+    "preview": {
+      "distribution": "internal",
+      "android": {
+        "buildType": "apk",
+        "withoutCredentials": true
+      },
+      "env": {
+        "ORG_GRADLE_PROJECT_reactNativeArchitectures": "arm64-v8a",
+        "EXPO_PUBLIC_API_URL": "https://calchat.gilmour109.de/api"
+      }
+    },
+    "production": {
+      "autoIncrement": true
+    }
+  },
+  "submit": {
+    "production": {}
+  }
+}

apps/client/package.json

@@ -1,5 +1,5 @@
 {
-  "name": "@caldav/client",
+  "name": "@calchat/client",
   "main": "expo-router/entry",
   "version": "1.0.0",
   "scripts": {
@@ -8,22 +8,26 @@
     "android": "expo start --android",
     "ios": "expo start --ios",
     "web": "expo start --web",
-    "lint": "expo lint"
+    "lint": "expo lint",
+    "build:apk": "eas build --platform android --profile preview --local"
   },
   "dependencies": {
-    "@caldav/shared": "*",
+    "@calchat/shared": "*",
     "@expo/vector-icons": "^15.0.3",
+    "@react-native-community/datetimepicker": "8.4.4",
     "@react-navigation/bottom-tabs": "^7.4.0",
     "@react-navigation/elements": "^2.6.3",
     "@react-navigation/native": "^7.1.8",
     "@shopify/flash-list": "^2.0.2",
     "expo": "~54.0.25",
+    "expo-build-properties": "^1.0.10",
     "expo-constants": "~18.0.10",
     "expo-font": "~14.0.9",
     "expo-haptics": "~15.0.7",
     "expo-image": "~3.0.10",
     "expo-linking": "~8.0.9",
     "expo-router": "~6.0.15",
+    "expo-secure-store": "^15.0.8",
     "expo-splash-screen": "~31.0.11",
     "expo-status-bar": "~3.0.8",
     "expo-symbols": "~1.0.7",
@@ -34,11 +38,13 @@
     "react-dom": "19.1.0",
     "react-native": "0.81.5",
     "react-native-gesture-handler": "~2.28.0",
+    "react-native-logs": "^5.5.0",
     "react-native-reanimated": "~4.1.1",
     "react-native-safe-area-context": "5.6.0",
     "react-native-screens": "~4.16.0",
     "react-native-web": "~0.21.0",
     "react-native-worklets": "0.5.1",
+    "rrule": "^2.8.1",
     "zustand": "^5.0.9"
   },
   "devDependencies": {

apps/client/src/Themes.tsx

@@ -1,4 +1,4 @@
-type Theme = {
+export type Theme = {
   chatBot: string;
   primeFg: string;
   primeBg: string;
@@ -15,26 +15,46 @@ type Theme = {
   textMuted: string;
   eventIndicator: string;
   borderPrimary: string;
+  shadowColor: string;
 };
 
-const defaultLight: Theme = {
+export const THEMES = {
-  chatBot: "#DE6C20",
+  defaultLight: {
-  primeFg: "#3B3329",
+    chatBot: "#DE6C20",
-  primeBg: "#FFEEDE",
+    primeFg: "#3B3329",
-  secondaryBg: "#FFFFFF",
+    primeBg: "#FFEEDE",
-  messageBorderBg: "#FFFFFF",
+    secondaryBg: "#FFFFFF",
-  placeholderBg: "#D9D9D9",
+    messageBorderBg: "#FFFFFF",
-  calenderBg: "#FBD5B2",
+    placeholderBg: "#D9D9D9",
-  confirmButton: "#22c55e",
+    calenderBg: "#FBD5B2",
-  rejectButton: "#ef4444",
+    confirmButton: "#22c55e",
-  disabledButton: "#ccc",
+    rejectButton: "#ef4444",
-  buttonText: "#fff",
+    disabledButton: "#ccc",
-  textPrimary: "#000000",
+    buttonText: "#000000",
-  textSecondary: "#666",
+    textPrimary: "#000000",
-  textMuted: "#888",
+    textSecondary: "#666",
-  eventIndicator: "#DE6C20",
+    textMuted: "#888",
-  borderPrimary: "#000000",
+    eventIndicator: "#DE6C20",
-};
+    borderPrimary: "#000000",
-
+    shadowColor: "#000000",
-let currentTheme: Theme = defaultLight;
+  },
-export default currentTheme;
+  defaultDark: {
+    chatBot: "#DE6C20",
+    primeFg: "#F5E6D3",
+    primeBg: "#1A1512",
+    secondaryBg: "#2A2420",
+    messageBorderBg: "#3A3430",
+    placeholderBg: "#4A4440",
+    calenderBg: "#3D2A1A",
+    confirmButton: "#136e34",
+    rejectButton: "#bd1010",
+    disabledButton: "#555",
+    buttonText: "#FFFFFF",
+    textPrimary: "#FFFFFF",
+    textSecondary: "#AAA",
+    textMuted: "#777",
+    eventIndicator: "#DE6C20",
+    borderPrimary: "#FFFFFF",
+    shadowColor: "#FFFFFF",
+  },
+} as const satisfies Record<string, Theme>;

apps/client/src/app/(tabs)/_layout.tsx

@@ -1,35 +1,48 @@
 import { Ionicons } from "@expo/vector-icons";
 import { Tabs } from "expo-router";
-import theme from "../../Themes";
+import { useThemeStore } from "../../stores/ThemeStore";
+import { AuthGuard } from "../../components/AuthGuard";
 
 export default function TabLayout() {
+  const { theme } = useThemeStore();
   return (
-    <Tabs
+    <AuthGuard>
-      screenOptions={{
+      <Tabs
-        headerShown: false,
+        screenOptions={{
-        tabBarActiveTintColor: theme.chatBot,
+          headerShown: false,
-        tabBarInactiveTintColor: theme.primeFg,
+          tabBarActiveTintColor: theme.chatBot,
-        tabBarStyle: { backgroundColor: theme.primeBg },
+          tabBarInactiveTintColor: theme.primeFg,
-      }}
+          tabBarStyle: { backgroundColor: theme.primeBg },
-    >
-      <Tabs.Screen
-        name="chat"
-        options={{
-          title: "Chat",
-          tabBarIcon: ({ color }) => (
-            <Ionicons size={28} name="chatbubble" color={color} />
-          ),
         }}
-      />
+      >
-      <Tabs.Screen
+        <Tabs.Screen
-        name="calendar"
+          name="chat"
-        options={{
+          options={{
-          title: "Calendar",
+            title: "Chat",
-          tabBarIcon: ({ color }) => (
+            tabBarIcon: ({ color }) => (
-            <Ionicons size={28} name="calendar" color={color} />
+              <Ionicons size={28} name="chatbubble" color={color} />
-          ),
+            ),
-        }}
+          }}
-      />
+        />
-    </Tabs>
+        <Tabs.Screen
+          name="calendar"
+          options={{
+            title: "Calendar",
+            tabBarIcon: ({ color }) => (
+              <Ionicons size={28} name="calendar" color={color} />
+            ),
+          }}
+        />
+        <Tabs.Screen
+          name="settings"
+          options={{
+            title: "Settings",
+            tabBarIcon: ({ color }) => (
+              <Ionicons size={28} name="settings" color={color} />
+            ),
+          }}
+        />
+      </Tabs>
+    </AuthGuard>
   );
 }

apps/client/src/app/(tabs)/calendar.tsx

@@ -1,29 +1,26 @@
+import { ActivityIndicator, Pressable, Text, View } from "react-native";
 import {
-  Animated,
+  DAYS,
-  Modal,
+  MONTHS,
-  Pressable,
+  Month,
-  Text,
+  ExpandedEvent,
-  View,
+  RecurringDeleteMode,
-  ScrollView,
+} from "@calchat/shared";
-  Alert,
-} from "react-native";
-import { DAYS, MONTHS, Month, ExpandedEvent } from "@caldav/shared";
 import Header from "../../components/Header";
 import { EventCard } from "../../components/EventCard";
-import React, {
+import { DeleteEventModal } from "../../components/DeleteEventModal";
-  useCallback,
+import { ModalBase } from "../../components/ModalBase";
-  useEffect,
+import { ScrollableDropdown } from "../../components/ScrollableDropdown";
-  useMemo,
+import React, { useCallback, useEffect, useMemo, useState } from "react";
-  useRef,
+import { router, useFocusEffect } from "expo-router";
-  useState,
-} from "react";
-import { useFocusEffect } from "expo-router";
 import { Ionicons } from "@expo/vector-icons";
-import currentTheme from "../../Themes";
+import { useThemeStore } from "../../stores/ThemeStore";
 import BaseBackground from "../../components/BaseBackground";
-import { FlashList } from "@shopify/flash-list";
+import { AuthService, EventService } from "../../services";
-import { EventService } from "../../services";
 import { useEventsStore } from "../../stores";
+import { useDropdownPosition } from "../../hooks/useDropdownPosition";
+import { CaldavConfigService } from "../../services/CaldavConfigService";
+import { useCaldavConfigStore } from "../../stores/CaldavConfigStore";
 
 // MonthSelector types and helpers
 type MonthItem = {
@@ -33,6 +30,14 @@ type MonthItem = {
   label: string; // e.g. "January 2024"
 };
 
+/**
+ * Formats a Date object to a string key in YYYY-MM-DD format.
+ * Used for grouping and looking up events by date.
+ */
+const getDateKey = (date: Date): string => {
+  return `${date.getFullYear()}-${String(date.getMonth() + 1).padStart(2, "0")}-${String(date.getDate()).padStart(2, "0")}`;
+};
+
 const generateMonths = (
   centerYear: number,
   centerMonth: number,
@@ -66,51 +71,77 @@ const Calendar = () => {
   const [monthIndex, setMonthIndex] = useState(new Date().getMonth());
   const [currentYear, setCurrentYear] = useState(new Date().getFullYear());
   const [selectedDate, setSelectedDate] = useState<Date | null>(null);
+  const [overlayVisible, setOverlayVisible] = useState(false);
+
+  // State for delete modal
+  const [deleteModalVisible, setDeleteModalVisible] = useState(false);
+  const [eventToDelete, setEventToDelete] = useState<ExpandedEvent | null>(
+    null,
+  );
 
   const { events, setEvents, deleteEvent } = useEventsStore();
 
-  // Load events when tab gains focus or month/year changes
+  // Load events from local DB (fast, no network sync)
-  // Include days from prev/next month that are visible in the grid
+  const loadEvents = useCallback(async () => {
+    try {
+      // Calculate first visible day (up to 6 days before month start)
+      const firstOfMonth = new Date(currentYear, monthIndex, 1);
+      const dayOfWeek = firstOfMonth.getDay();
+      const daysFromPrevMonth = dayOfWeek === 0 ? 6 : dayOfWeek - 1;
+      const startDate = new Date(
+        currentYear,
+        monthIndex,
+        1 - daysFromPrevMonth,
+      );
+
+      // Calculate last visible day (6 weeks * 7 days = 42 days total)
+      const endDate = new Date(startDate);
+      endDate.setDate(startDate.getDate() + 41);
+      endDate.setHours(23, 59, 59);
+
+      const loadedEvents = await EventService.getByDateRange(
+        startDate,
+        endDate,
+      );
+      setEvents(loadedEvents);
+    } catch (error) {
+      console.error("Failed to load events:", error);
+    }
+  }, [monthIndex, currentYear, setEvents]);
+
+  // Load events from DB on focus
   useFocusEffect(
     useCallback(() => {
-      const loadEvents = async () => {
-        try {
-          // Calculate first visible day (up to 6 days before month start)
-          const firstOfMonth = new Date(currentYear, monthIndex, 1);
-          const dayOfWeek = firstOfMonth.getDay();
-          const daysFromPrevMonth = dayOfWeek === 0 ? 6 : dayOfWeek - 1;
-          const startDate = new Date(
-            currentYear,
-            monthIndex,
-            1 - daysFromPrevMonth,
-          );
-
-          // Calculate last visible day (6 weeks * 7 days = 42 days total)
-          const endDate = new Date(startDate);
-          endDate.setDate(startDate.getDate() + 41);
-          endDate.setHours(23, 59, 59);
-
-          const loadedEvents = await EventService.getByDateRange(
-            startDate,
-            endDate,
-          );
-          setEvents(loadedEvents);
-        } catch (error) {
-          console.error("Failed to load events:", error);
-        }
-      };
       loadEvents();
-    }, [monthIndex, currentYear, setEvents]),
+    }, [loadEvents]),
+  );
+
+  // Re-open overlay after back navigation from editEvent
+  useFocusEffect(
+    useCallback(() => {
+      if (selectedDate) {
+        setOverlayVisible(true);
+      }
+    }, [selectedDate]),
   );
 
   // Group events by date (YYYY-MM-DD format)
+  // Multi-day events are added to all days they span
   const eventsByDate = useMemo(() => {
     const map = new Map<string, ExpandedEvent[]>();
     events.forEach((e) => {
-      const date = new Date(e.occurrenceStart);
+      const start = new Date(e.occurrenceStart);
-      const key = `${date.getFullYear()}-${String(date.getMonth() + 1).padStart(2, "0")}-${String(date.getDate()).padStart(2, "0")}`;
+      const end = new Date(e.occurrenceEnd);
-      if (!map.has(key)) map.set(key, []);
+
-      map.get(key)!.push(e);
+      // Iterate through each day the event spans
+      const current = new Date(start);
+      current.setHours(0, 0, 0, 0);
+      while (current <= end) {
+        const key = getDateKey(current);
+        if (!map.has(key)) map.set(key, []);
+        map.get(key)!.push(e);
+        current.setDate(current.getDate() + 1);
+      }
     });
     return map;
   }, [events]);
@@ -130,52 +161,74 @@ const Calendar = () => {
     });
   };
 
-  const handleDayPress = (date: Date, hasEvents: boolean) => {
+  const handleDayPress = (date: Date) => {
-    if (hasEvents) {
+    setSelectedDate(date);
-      setSelectedDate(date);
+    setOverlayVisible(true);
-    }
   };
 
   const handleCloseOverlay = () => {
     setSelectedDate(null);
+    setOverlayVisible(false);
   };
 
-  const handleEditEvent = (event: ExpandedEvent) => {
+  const handleCreateEvent = () => {
-    console.log("Edit event:", event.id);
+    setOverlayVisible(false);
-    // TODO: Navigate to event edit screen
+    router.push({
+      pathname: "/editEvent",
+      params: { date: selectedDate?.toISOString() },
+    });
   };
 
-  const handleDeleteEvent = async (event: ExpandedEvent) => {
+  const handleEditEvent = (event?: ExpandedEvent) => {
-    Alert.alert("Event löschen", `"${event.title}" wirklich löschen?`, [
+    router.push({
-      { text: "Abbrechen", style: "cancel" },
+      pathname: "/editEvent",
-      {
+      params: {
-        text: "Löschen",
+        mode: "calendar",
-        style: "destructive",
+        id: event?.id,
-        onPress: async () => {
-          try {
-            await EventService.delete(event.id);
-            deleteEvent(event.id);
-            // Close overlay if no more events for this date
-            if (selectedDate) {
-              const dateKey = `${selectedDate.getFullYear()}-${String(selectedDate.getMonth() + 1).padStart(2, "0")}-${String(selectedDate.getDate()).padStart(2, "0")}`;
-              const remainingEvents = eventsByDate.get(dateKey) || [];
-              if (remainingEvents.length <= 1) {
-                setSelectedDate(null);
-              }
-            }
-          } catch (error) {
-            console.error("Failed to delete event:", error);
-            Alert.alert("Fehler", "Event konnte nicht gelöscht werden");
-          }
-        },
       },
-    ]);
+    });
+  };
+
+  const handleDeleteEvent = (event: ExpandedEvent) => {
+    // Show delete modal for both recurring and non-recurring events
+    setEventToDelete(event);
+    setDeleteModalVisible(true);
+  };
+
+  const handleDeleteConfirm = async (mode: RecurringDeleteMode) => {
+    if (!eventToDelete) return;
+
+    setDeleteModalVisible(false);
+    const event = eventToDelete;
+    const occurrenceDate = getDateKey(new Date(event.occurrenceStart));
+
+    try {
+      if (event.recurrenceRule) {
+        // Recurring event: use mode and occurrenceDate
+        await EventService.delete(event.id, mode, occurrenceDate);
+        // Reload events to reflect changes
+        await loadEvents();
+      } else {
+        // Non-recurring event: simple delete
+        await EventService.delete(event.id);
+        deleteEvent(event.id);
+      }
+    } catch (error) {
+      console.error("Failed to delete event:", error);
+    }
+    // Note: Don't clear eventToDelete here - it will be overwritten when opening a new modal.
+    // Clearing it during fade-out animation causes the modal content to flash from recurring to single.
+  };
+
+  const handleDeleteCancel = () => {
+    setDeleteModalVisible(false);
+    // Note: Don't clear eventToDelete - keeps modal content stable during fade-out animation
   };
 
   // Get events for selected date
   const selectedDateEvents = useMemo(() => {
     if (!selectedDate) return [];
-    const key = `${selectedDate.getFullYear()}-${String(selectedDate.getMonth() + 1).padStart(2, "0")}-${String(selectedDate.getDate()).padStart(2, "0")}`;
+    const key = getDateKey(selectedDate);
     return eventsByDate.get(key) || [];
   }, [selectedDate, eventsByDate]);
 
@@ -188,6 +241,7 @@ const Calendar = () => {
         setMonthIndex={setMonthIndex}
         setYear={setCurrentYear}
       />
+      <CalendarToolbar loadEvents={loadEvents} />
       <WeekDaysLine />
       <CalendarGrid
         month={MONTHS[monthIndex]}
@@ -195,15 +249,21 @@ const Calendar = () => {
         eventsByDate={eventsByDate}
         onDayPress={handleDayPress}
       />
-
-      {/* Event Overlay Modal */}
       <EventOverlay
-        visible={selectedDate !== null}
+        visible={overlayVisible && !deleteModalVisible}
         date={selectedDate}
         events={selectedDateEvents}
         onClose={handleCloseOverlay}
         onEditEvent={handleEditEvent}
         onDeleteEvent={handleDeleteEvent}
+        onCreateEvent={handleCreateEvent}
+      />
+      <DeleteEventModal
+        visible={deleteModalVisible}
+        eventTitle={eventToDelete?.title || ""}
+        isRecurring={!!eventToDelete?.recurrenceRule}
+        onConfirm={handleDeleteConfirm}
+        onCancel={handleDeleteCancel}
       />
     </BaseBackground>
   );
@@ -214,8 +274,9 @@ type EventOverlayProps = {
   date: Date | null;
   events: ExpandedEvent[];
   onClose: () => void;
-  onEditEvent: (event: ExpandedEvent) => void;
+  onEditEvent: (event?: ExpandedEvent) => void;
   onDeleteEvent: (event: ExpandedEvent) => void;
+  onCreateEvent: () => void;
 };
 
 const EventOverlay = ({
@@ -225,7 +286,10 @@ const EventOverlay = ({
   onClose,
   onEditEvent,
   onDeleteEvent,
+  onCreateEvent,
 }: EventOverlayProps) => {
+  const { theme } = useThemeStore();
+
   if (!date) return null;
 
   const dateString = date.toLocaleDateString("de-DE", {
@@ -235,70 +299,41 @@ const EventOverlay = ({
     year: "numeric",
   });
 
-  return (
+  const subtitle = `${events.length} ${events.length === 1 ? "Termin" : "Termine"}`;
-    <Modal
+
-      visible={visible}
+  const addEventAttachment = (
-      transparent={true}
+    <Pressable
-      animationType="fade"
+      className="flex flex-row justify-center items-center py-3"
-      onRequestClose={onClose}
+      style={{ backgroundColor: theme.confirmButton }}
+      onPress={onCreateEvent}
     >
-      <Pressable
+      <Ionicons name="add-outline" size={24} color={theme.buttonText} />
-        className="flex-1 justify-center items-center"
+      <Text style={{ color: theme.buttonText }} className="font-semibold ml-1">
-        style={{ backgroundColor: "rgba(0,0,0,0.5)" }}
+        Neuen Termin erstellen
-        onPress={onClose}
+      </Text>
-      >
+    </Pressable>
-        <Pressable
+  );
-          className="w-11/12 max-h-3/4 rounded-2xl overflow-hidden"
-          style={{
-            backgroundColor: currentTheme.primeBg,
-            borderWidth: 4,
-            borderColor: currentTheme.borderPrimary,
-          }}
-          onPress={(e) => e.stopPropagation()}
-        >
-          {/* Header */}
-          <View
-            className="px-4 py-3"
-            style={{
-              backgroundColor: currentTheme.chatBot,
-              borderBottomWidth: 3,
-              borderBottomColor: currentTheme.borderPrimary,
-            }}
-          >
-            <Text className="font-bold text-lg">{dateString}</Text>
-            <Text>
-              {events.length} {events.length === 1 ? "Termin" : "Termine"}
-            </Text>
-          </View>
 
-          {/* Events List */}
+  return (
-          <ScrollView className="p-4" style={{ maxHeight: 400 }}>
+    <ModalBase
-            {events.map((event, index) => (
+      visible={visible}
-              <EventCard
+      onClose={onClose}
-                key={`${event.id}-${index}`}
+      title={dateString}
-                event={event}
+      subtitle={subtitle}
-                onEdit={() => onEditEvent(event)}
+      attachment={addEventAttachment}
-                onDelete={() => onDeleteEvent(event)}
+      footer={{ label: "Schliessen", onPress: onClose }}
-              />
+      scrollable={true}
-            ))}
+      maxContentHeight={400}
-          </ScrollView>
+    >
-
+      {events.map((event, index) => (
-          {/* Close button */}
+        <EventCard
-          <Pressable
+          key={`${event.id}-${index}`}
-            onPress={onClose}
+          event={event}
-            className="py-3 items-center"
+          onEdit={() => onEditEvent(event)}
-            style={{
+          onDelete={() => onDeleteEvent(event)}
-              borderTopWidth: 1,
+        />
-              borderTopColor: currentTheme.placeholderBg,
+      ))}
-            }}
+    </ModalBase>
-          >
-            <Text style={{ color: currentTheme.primeFg }} className="font-bold">
-              Schließen
-            </Text>
-          </Pressable>
-        </Pressable>
-      </Pressable>
-    </Modal>
   );
 };
 
@@ -311,6 +346,8 @@ type MonthSelectorProps = {
   onSelectMonth: (year: number, monthIndex: number) => void;
 };
 
+const INITIAL_RANGE = 12; // 12 months before and after current
+
 const MonthSelector = ({
   modalVisible,
   onClose,
@@ -319,132 +356,98 @@ const MonthSelector = ({
   currentMonthIndex,
   onSelectMonth,
 }: MonthSelectorProps) => {
-  const heightAnim = useRef(new Animated.Value(0)).current;
-  const listRef = useRef<React.ComponentRef<typeof FlashList<MonthItem>>>(null);
-  const INITIAL_RANGE = 12; // 12 months before and after current
-
   const [monthSelectorData, setMonthSelectorData] = useState<MonthItem[]>([]);
 
-  const appendMonths = (direction: "start" | "end", count: number) => {
+  const appendMonths = useCallback(
-    setMonthSelectorData((prevData) => {
+    (direction: "start" | "end", count: number) => {
-      if (prevData.length === 0) return prevData;
+      setMonthSelectorData((prevData) => {
+        if (prevData.length === 0) return prevData;
 
-      const newMonths: MonthItem[] = [];
+        const newMonths: MonthItem[] = [];
-      const referenceMonth =
+        const referenceMonth =
-        direction === "start" ? prevData[0] : prevData[prevData.length - 1];
+          direction === "start" ? prevData[0] : prevData[prevData.length - 1];
 
-      for (let i = 1; i <= count; i++) {
+        for (let i = 1; i <= count; i++) {
-        const offset = direction === "start" ? -i : i;
+          const offset = direction === "start" ? -i : i;
-        let year = referenceMonth.year;
+          let year = referenceMonth.year;
-        let month = referenceMonth.monthIndex + offset;
+          let month = referenceMonth.monthIndex + offset;
 
-        while (month < 0) {
+          while (month < 0) {
-          month += 12;
+            month += 12;
-          year--;
+            year--;
-        }
+          }
-        while (month > 11) {
+          while (month > 11) {
-          month -= 12;
+            month -= 12;
-          year++;
+            year++;
+          }
+
+          const newMonth: MonthItem = {
+            id: `${year}-${String(month + 1).padStart(2, "0")}`,
+            year,
+            monthIndex: month,
+            label: `${MONTHS[month]} ${year}`,
+          };
+
+          if (direction === "start") {
+            newMonths.unshift(newMonth);
+          } else {
+            newMonths.push(newMonth);
+          }
         }
 
-        const newMonth: MonthItem = {
+        return direction === "start"
-          id: `${year}-${String(month + 1).padStart(2, "0")}`,
+          ? [...newMonths, ...prevData]
-          year,
+          : [...prevData, ...newMonths];
-          monthIndex: month,
+      });
-          label: `${MONTHS[month]} ${year}`,
+    },
-        };
+    [],
-
+  );
-        if (direction === "start") {
-          newMonths.unshift(newMonth);
-        } else {
-          newMonths.push(newMonth);
-        }
-      }
-
-      return direction === "start"
-        ? [...newMonths, ...prevData]
-        : [...prevData, ...newMonths];
-    });
-  };
 
+  // Generate fresh data when modal opens, clear when closes
   useEffect(() => {
     if (modalVisible) {
-      // Generate fresh data centered on current month
       setMonthSelectorData(
         generateMonths(currentYear, currentMonthIndex, INITIAL_RANGE),
       );
-      Animated.timing(heightAnim, {
-        toValue: 200,
-        duration: 200,
-        useNativeDriver: false,
-      }).start();
     } else {
-      heightAnim.setValue(0);
-      // Clear data when closing
       setMonthSelectorData([]);
     }
-  }, [modalVisible, heightAnim, currentYear, currentMonthIndex]);
+  }, [modalVisible, currentYear, currentMonthIndex]);
 
-  const renderItem = ({ item }: { item: MonthItem }) => (
+  const handleSelect = useCallback(
-    <Pressable
+    (item: MonthItem) => {
-      onPress={() => {
+      onSelectMonth(item.year, item.monthIndex);
-        onSelectMonth(item.year, item.monthIndex);
+      onClose();
-        onClose();
+    },
-      }}
+    [onSelectMonth, onClose],
-    >
-      <View
-        className="w-full flex justify-center items-center py-2"
-        style={{
-          backgroundColor:
-            item.monthIndex % 2 === 0
-              ? currentTheme.primeBg
-              : currentTheme.secondaryBg,
-        }}
-      >
-        <Text className="text-xl" style={{ color: currentTheme.primeFg }}>
-          {item.label}
-        </Text>
-      </View>
-    </Pressable>
   );
 
   return (
-    <Modal
+    <ScrollableDropdown
       visible={modalVisible}
-      transparent={true}
+      onClose={onClose}
-      animationType="none"
+      position={position}
-      onRequestClose={onClose}
+      data={monthSelectorData}
-    >
+      keyExtractor={(item) => item.id}
-      <Pressable className="flex-1 rounded-lg" onPress={onClose}>
+      renderItem={(item, theme) => (
-        <Animated.View
+        <View
-          className="absolute overflow-hidden"
+          className="w-full flex justify-center items-center py-2"
           style={{
-            top: position.top,
+            backgroundColor:
-            left: position.left,
+              item.monthIndex % 2 === 0 ? theme.primeBg : theme.secondaryBg,
-            width: position.width,
-            height: heightAnim,
-            backgroundColor: currentTheme.primeBg,
-            borderWidth: 2,
-            borderColor: currentTheme.borderPrimary,
-            borderRadius: 8,
           }}
         >
-          <FlashList
+          <Text className="text-xl" style={{ color: theme.primeFg }}>
-            className="w-full"
+            {item.label}
-            style={{ borderRadius: 8 }}
+          </Text>
-            ref={listRef}
+        </View>
-            keyExtractor={(item) => item.id}
+      )}
-            data={monthSelectorData}
+      onSelect={handleSelect}
-            initialScrollIndex={INITIAL_RANGE}
+      height={200}
-            onEndReachedThreshold={0.5}
+      initialScrollIndex={INITIAL_RANGE}
-            onEndReached={() => appendMonths("end", 12)}
+      onEndReached={() => appendMonths("end", 12)}
-            onStartReachedThreshold={0.5}
+      onStartReached={() => appendMonths("start", 12)}
-            onStartReached={() => appendMonths("start", 12)}
+    />
-            renderItem={renderItem}
-          />
-        </Animated.View>
-      </Pressable>
-    </Modal>
   );
 };
 
@@ -457,60 +460,44 @@ type CalendarHeaderProps = {
 };
 
 const CalendarHeader = (props: CalendarHeaderProps) => {
-  const [modalVisible, setModalVisible] = useState(false);
+  const { theme } = useThemeStore();
-  const [dropdownPosition, setDropdownPosition] = useState({
+  const dropdown = useDropdownPosition();
-    top: 0,
-    left: 0,
-    width: 0,
-  });
-  const containerRef = useRef<View>(null);
 
   const prevMonth = () => props.changeMonth(-1);
   const nextMonth = () => props.changeMonth(1);
 
-  const measureAndOpen = () => {
-    containerRef.current?.measureInWindow((x, y, width, height) => {
-      setDropdownPosition({ top: y + height, left: x, width });
-      setModalVisible(true);
-    });
-  };
-
   return (
     <Header className="flex flex-row items-center justify-between">
       <ChangeMonthButton onPress={prevMonth} icon="chevron-back" />
       <View
-        ref={containerRef}
+        ref={dropdown.ref}
         className="relative flex flex-row items-center justify-around"
       >
-        <Text className="text-4xl px-1">
+        <Text className="text-4xl px-1" style={{ color: theme.textPrimary }}>
           {MONTHS[props.monthIndex]} {props.currentYear}
         </Text>
         <Pressable
           className="flex justify-center items-center w-12 h-12 border rounded-lg"
           style={{
-            borderColor: currentTheme.primeFg,
+            borderColor: theme.primeFg,
-            backgroundColor: currentTheme.chatBot,
+            backgroundColor: theme.chatBot,
             // iOS shadow
-            shadowColor: "#000",
+            shadowColor: theme.shadowColor,
             shadowOffset: { width: 0, height: 3 },
             shadowOpacity: 0.35,
             shadowRadius: 5,
             // Android shadow
             elevation: 6,
           }}
-          onPress={measureAndOpen}
+          onPress={dropdown.open}
         >
-          <Ionicons
+          <Ionicons name="chevron-down" size={28} color={theme.primeFg} />
-            name="chevron-down"
-            size={28}
-            color={currentTheme.primeFg}
-          />
         </Pressable>
       </View>
       <MonthSelector
-        modalVisible={modalVisible}
+        modalVisible={dropdown.visible}
-        onClose={() => setModalVisible(false)}
+        onClose={dropdown.close}
-        position={dropdownPosition}
+        position={dropdown.position}
         currentYear={props.currentYear}
         currentMonthIndex={props.monthIndex}
         onSelectMonth={(year, month) => {
@@ -528,51 +515,185 @@ type ChangeMonthButtonProps = {
   icon: "chevron-back" | "chevron-forward";
 };
 
-const ChangeMonthButton = (props: ChangeMonthButtonProps) => (
+const ChangeMonthButton = (props: ChangeMonthButtonProps) => {
-  <Pressable
+  const { theme } = useThemeStore();
-    onPress={props.onPress}
+  return (
-    className="w-16 h-16 flex items-center justify-center mx-2 rounded-xl border border-solid"
+    <Pressable
-    style={{
+      onPress={props.onPress}
-      backgroundColor: currentTheme.chatBot,
+      className="w-16 h-16 flex items-center justify-center mx-2 rounded-xl border border-solid"
-      borderColor: currentTheme.primeFg,
-      // iOS shadow
-      shadowColor: "#000",
-      shadowOffset: { width: 0, height: 4 },
-      shadowOpacity: 0.3,
-      shadowRadius: 8,
-      // Android shadow
-      elevation: 6,
-    }}
-  >
-    <Ionicons
-      name={props.icon}
-      size={48}
-      color={currentTheme.primeFg}
       style={{
-        marginLeft: props.icon === "chevron-forward" ? 4 : 0,
+        backgroundColor: theme.chatBot,
-        marginRight: props.icon === "chevron-back" ? 4 : 0,
+        borderColor: theme.primeFg,
+        // iOS shadow
+        shadowColor: theme.shadowColor,
+        shadowOffset: { width: 0, height: 4 },
+        shadowOpacity: 0.3,
+        shadowRadius: 8,
+        // Android shadow
+        elevation: 6,
       }}
-    />
+    >
-  </Pressable>
+      <Ionicons
-);
+        name={props.icon}
+        size={48}
+        color={theme.primeFg}
+        style={{
+          marginLeft: props.icon === "chevron-forward" ? 4 : 0,
+          marginRight: props.icon === "chevron-back" ? 4 : 0,
+        }}
+      />
+    </Pressable>
+  );
+};
 
-const WeekDaysLine = () => (
+type CalendarToolbarProps = {
-  <View className="flex flex-row items-center justify-around px-2 gap-2">
+  loadEvents: () => Promise<void>;
-    {/* TODO: px and gap need fine tuning to perfectly align with the grid */}
+};
-    {DAYS.map((day, i) => (
+
-      <Text key={i}>{day.substring(0, 2).toUpperCase()}</Text>
+const CalendarToolbar = ({ loadEvents }: CalendarToolbarProps) => {
-    ))}
+  const { theme } = useThemeStore();
-  </View>
+  const { config } = useCaldavConfigStore();
-);
+  const [isSyncing, setIsSyncing] = useState(false);
+  const [syncResult, setSyncResult] = useState<"success" | "error" | null>(
+    null,
+  );
+
+  const handleSync = async () => {
+    if (!config || isSyncing) return;
+    setSyncResult(null);
+    setIsSyncing(true);
+    try {
+      await CaldavConfigService.sync();
+      await loadEvents();
+      setSyncResult("success");
+    } catch (error) {
+      console.error("CalDAV sync failed:", error);
+      setSyncResult("error");
+    } finally {
+      setIsSyncing(false);
+    }
+  };
+
+  useEffect(() => {
+    if (!syncResult) return;
+    const timer = setTimeout(() => setSyncResult(null), 3000);
+    return () => clearTimeout(timer);
+  }, [syncResult]);
+
+  const handleLogout = async () => {
+    await AuthService.logout();
+    router.replace("/login");
+  };
+
+  const syncIcon = () => {
+    if (isSyncing) {
+      return <ActivityIndicator size="small" color={theme.primeFg} />;
+    }
+    if (syncResult === "success") {
+      return (
+        <Ionicons
+          name="checkmark-circle"
+          size={20}
+          color={theme.confirmButton}
+        />
+      );
+    }
+    if (syncResult === "error") {
+      return (
+        <Ionicons name="close-circle" size={20} color={theme.rejectButton} />
+      );
+    }
+    return (
+      <Ionicons
+        name="sync-outline"
+        size={20}
+        color={config ? theme.primeFg : theme.textMuted}
+      />
+    );
+  };
+
+  const buttonStyle = {
+    backgroundColor: theme.chatBot,
+    borderColor: theme.borderPrimary,
+    borderWidth: 1,
+    shadowColor: theme.shadowColor,
+    shadowOffset: { width: 0, height: 2 },
+    shadowOpacity: 0.25,
+    shadowRadius: 4,
+    elevation: 4,
+  };
+
+  const className = "flex flex-row items-center gap-2 px-3 py-1 rounded-lg";
+
+  return (
+    <View
+      className="flex flex-row items-center justify-around py-2"
+      style={{
+        backgroundColor: theme.primeBg,
+        borderBottomWidth: 0,
+        borderBottomColor: theme.borderPrimary,
+      }}
+    >
+      <Pressable
+        onPress={handleSync}
+        disabled={!config || isSyncing}
+        className={className}
+        style={{
+          ...buttonStyle,
+          ...(config
+            ? {}
+            : {
+                backgroundColor: theme.disabledButton,
+                borderColor: theme.disabledButton,
+              }),
+        }}
+      >
+        {syncIcon()}
+        <Text
+          style={{ color: config ? theme.textPrimary : theme.textMuted }}
+          className="font-medium"
+        >
+          Sync
+        </Text>
+      </Pressable>
+
+      <Pressable
+        onPress={handleLogout}
+        className={className}
+        style={buttonStyle}
+      >
+        <Ionicons name="log-out-outline" size={20} color={theme.primeFg} />
+        <Text style={{ color: theme.textPrimary }} className="font-medium">
+          Logout
+        </Text>
+      </Pressable>
+    </View>
+  );
+};
+
+const WeekDaysLine = () => {
+  const { theme } = useThemeStore();
+  return (
+    <View className="flex flex-row items-center justify-around px-2 gap-2">
+      {/* TODO: px and gap need fine tuning to perfectly align with the grid */}
+      {DAYS.map((day, i) => (
+        <Text key={i} style={{ color: theme.textPrimary }}>
+          {day.substring(0, 2).toUpperCase()}
+        </Text>
+      ))}
+    </View>
+  );
+};
 
 type CalendarGridProps = {
   month: Month;
   year: number;
   eventsByDate: Map<string, ExpandedEvent[]>;
-  onDayPress: (date: Date, hasEvents: boolean) => void;
+  onDayPress: (date: Date) => void;
 };
 
 const CalendarGrid = (props: CalendarGridProps) => {
+  const { theme } = useThemeStore();
   const { baseDate, dateOffset } = useMemo(() => {
     const monthIndex = MONTHS.indexOf(props.month);
     const base = new Date(props.year, monthIndex, 1);
@@ -587,15 +708,11 @@ const CalendarGrid = (props: CalendarGridProps) => {
     return date;
   };
 
-  const getDateKey = (date: Date): string => {
-    return `${date.getFullYear()}-${String(date.getMonth() + 1).padStart(2, "0")}-${String(date.getDate()).padStart(2, "0")}`;
-  };
-
   return (
     <View
       className="h-full flex-1 flex-col flex-wrap gap-2 p-2"
       style={{
-        backgroundColor: currentTheme.calenderBg,
+        backgroundColor: theme.calenderBg,
       }}
     >
       {Array.from({ length: 6 }).map((_, i) => (
@@ -613,7 +730,7 @@ const CalendarGrid = (props: CalendarGridProps) => {
                 date={date}
                 month={props.month}
                 hasEvents={hasEvents}
-                onPress={() => props.onDayPress(date, hasEvents)}
+                onPress={() => props.onDayPress(date)}
               />
             );
           })}
@@ -631,6 +748,7 @@ type SingleDayProps = {
 };
 
 const SingleDay = (props: SingleDayProps) => {
+  const { theme } = useThemeStore();
   const isSameMonth = MONTHS[props.date.getMonth()] === props.month;
 
   return (
@@ -638,11 +756,12 @@ const SingleDay = (props: SingleDayProps) => {
       onPress={props.onPress}
       className="h-full flex-1 aspect-auto rounded-xl items-center justify-between py-1"
       style={{
-        backgroundColor: currentTheme.primeBg,
+        backgroundColor: theme.primeBg,
       }}
     >
       <Text
-        className={`text-xl ` + (isSameMonth ? "text-black" : "text-black/50")}
+        className="text-xl"
+        style={{ color: theme.textPrimary, opacity: isSameMonth ? 1 : 0.5 }}
       >
         {props.date.getDate()}
       </Text>
@@ -651,7 +770,7 @@ const SingleDay = (props: SingleDayProps) => {
       {props.hasEvents && (
         <View
           className="w-2 h-2 rounded-full"
-          style={{ backgroundColor: currentTheme.eventIndicator }}
+          style={{ backgroundColor: theme.eventIndicator }}
         />
       )}
     </Pressable>

apps/client/src/app/(tabs)/chat.tsx

@@ -7,19 +7,24 @@ import {
   Platform,
   Keyboard,
 } from "react-native";
-import currentTheme from "../../Themes";
+import { useThemeStore } from "../../stores/ThemeStore";
-import React, { useState, useRef, useEffect } from "react";
+import React, { useState, useRef, useEffect, useCallback } from "react";
+import { useFocusEffect, router } from "expo-router";
 import Header from "../../components/Header";
 import BaseBackground from "../../components/BaseBackground";
 import { FlashList } from "@shopify/flash-list";
 import { ChatService } from "../../services";
 import {
   useChatStore,
+  useAuthStore,
   chatMessageToMessageData,
   MessageData,
 } from "../../stores";
-import { ProposedEventChange } from "@caldav/shared";
+import { ProposedEventChange, RespondedAction } from "@calchat/shared";
 import { ProposedEventCard } from "../../components/ProposedEventCard";
+import { Ionicons } from "@expo/vector-icons";
+import TypingIndicator from "../../components/TypingIndicator";
+import { ChatBubble } from "../../components/ChatBubble";
 
 // TODO: better shadows for everything
 // (maybe with extra library because of differences between android and ios)
@@ -30,68 +35,94 @@ type BubbleSide = "left" | "right";
 type ChatMessageProps = {
   side: BubbleSide;
   content: string;
-  proposedChange?: ProposedEventChange;
+  proposedChanges?: ProposedEventChange[];
-  respondedAction?: "confirm" | "reject";
+  onConfirm?: (proposalId: string, proposal: ProposedEventChange) => void;
-  onConfirm?: () => void;
+  onReject?: (proposalId: string) => void;
-  onReject?: () => void;
+  onEdit?: (proposalId: string, proposal: ProposedEventChange) => void;
 };
 
 type ChatInputProps = {
   onSend: (text: string) => void;
 };
 
+const TYPING_INDICATOR_DELAY_MS = 500;
+
 const Chat = () => {
-  const { messages, addMessage, addMessages, updateMessage } = useChatStore();
+  const { isAuthenticated, isLoading: isAuthLoading } = useAuthStore();
+  const {
+    messages,
+    addMessage,
+    addMessages,
+    updateMessage,
+    isWaitingForResponse,
+    setWaitingForResponse,
+  } = useChatStore();
   const listRef =
     useRef<React.ComponentRef<typeof FlashList<MessageData>>>(null);
+  const typingTimeoutRef = useRef<ReturnType<typeof setTimeout>>(undefined);
   const [currentConversationId, setCurrentConversationId] = useState<
     string | undefined
   >();
+  const [hasLoadedMessages, setHasLoadedMessages] = useState(false);
+  const needsInitialScroll = useRef(false);
 
   useEffect(() => {
-    const keyboardDidShow = Keyboard.addListener(
+    const keyboardDidShow = Keyboard.addListener("keyboardDidShow", () =>
-      "keyboardDidShow",
+      scrollToEnd(),
-      scrollToEnd,
     );
     return () => keyboardDidShow.remove();
   }, []);
 
-  // Load existing messages from database on mount
+  // Load existing messages from database only once (on initial mount)
-  useEffect(() => {
+  // Skip on subsequent focus events to preserve local edits (e.g., edited proposals)
-    const fetchMessages = async () => {
+  useFocusEffect(
-      try {
+    useCallback(() => {
-        const conversationSummaries = await ChatService.getConversations();
+      if (isAuthLoading || !isAuthenticated || hasLoadedMessages) return;
-        if (conversationSummaries.length > 0) {
-          const conversationId = conversationSummaries[0].id;
-          setCurrentConversationId(conversationId);
 
-          const serverMessages =
+      const fetchMessages = async () => {
-            await ChatService.getConversation(conversationId);
+        try {
-          const clientMessages = serverMessages.map(chatMessageToMessageData);
+          const conversationSummaries = await ChatService.getConversations();
-          addMessages(clientMessages);
+          if (conversationSummaries.length > 0) {
-          scrollToEnd();
+            const conversationId = conversationSummaries[0].id;
+            setCurrentConversationId(conversationId);
+
+            const serverMessages =
+              await ChatService.getConversation(conversationId);
+            const clientMessages = serverMessages.map(chatMessageToMessageData);
+            addMessages(clientMessages);
+            needsInitialScroll.current = true;
+          }
+        } catch (error) {
+          console.error("Failed to load messages:", error);
+        } finally {
+          setHasLoadedMessages(true);
         }
-      } catch (error) {
+      };
-        console.error("Failed to load messages:", error);
+      fetchMessages();
-      }
+    }, [isAuthLoading, isAuthenticated, hasLoadedMessages]),
-    };
+  );
-    fetchMessages();
-  }, []);
 
-  const scrollToEnd = () => {
+  const scrollToEnd = (animated = true) => {
     setTimeout(() => {
-      listRef.current?.scrollToEnd({ animated: true });
+      listRef.current?.scrollToEnd({ animated });
     }, 100);
   };
 
   const handleEventResponse = async (
-    action: "confirm" | "reject",
+    action: RespondedAction,
     messageId: string,
     conversationId: string,
+    proposalId: string,
     proposedChange?: ProposedEventChange,
   ) => {
-    // Mark message as responded (optimistic update)
+    // Mark proposal as responded (optimistic update)
-    updateMessage(messageId, { respondedAction: action });
+    const message = messages.find((m) => m.id === messageId);
+    if (message?.proposedChanges) {
+      const updatedProposals = message.proposedChanges.map((p) =>
+        p.id === proposalId ? { ...p, respondedAction: action } : p,
+      );
+      updateMessage(messageId, { proposedChanges: updatedProposals });
+    }
 
     try {
       const response =
@@ -99,12 +130,19 @@ const Chat = () => {
           ? await ChatService.confirmEvent(
               conversationId,
               messageId,
+              proposalId,
               proposedChange.action,
               proposedChange.event,
               proposedChange.eventId,
               proposedChange.updates,
+              proposedChange.deleteMode,
+              proposedChange.occurrenceDate,
             )
-          : await ChatService.rejectEvent(conversationId, messageId);
+          : await ChatService.rejectEvent(
+              conversationId,
+              messageId,
+              proposalId,
+            );
 
       const botMessage: MessageData = {
         id: response.message.id,
@@ -117,10 +155,35 @@ const Chat = () => {
     } catch (error) {
       console.error(`Failed to ${action} event:`, error);
       // Revert on error
-      updateMessage(messageId, { respondedAction: undefined });
+      if (message?.proposedChanges) {
+        const revertedProposals = message.proposedChanges.map((p) =>
+          p.id === proposalId ? { ...p, respondedAction: undefined } : p,
+        );
+        updateMessage(messageId, { proposedChanges: revertedProposals });
+      }
     }
   };
 
+  const handleEditProposal = (
+    messageId: string,
+    conversationId: string,
+    proposalId: string,
+    proposal: ProposedEventChange,
+  ) => {
+    router.push({
+      pathname: "/editEvent",
+      params: {
+        mode: "chat",
+        eventData: JSON.stringify(proposal.event),
+        proposalContext: JSON.stringify({
+          messageId,
+          proposalId,
+          conversationId,
+        }),
+      },
+    });
+  };
+
   const handleSend = async (text: string) => {
     // Show user message immediately
     const userMessage: MessageData = {
@@ -132,6 +195,12 @@ const Chat = () => {
     addMessage(userMessage);
     scrollToEnd();
 
+    // Show typing indicator after delay
+    typingTimeoutRef.current = setTimeout(() => {
+      setWaitingForResponse(true);
+      scrollToEnd();
+    }, TYPING_INDICATOR_DELAY_MS);
+
     try {
       // Fetch server response (include conversationId for existing conversations)
       const response = await ChatService.sendMessage({
@@ -149,13 +218,17 @@ const Chat = () => {
         id: response.message.id,
         side: "left",
         content: response.message.content,
-        proposedChange: response.message.proposedChange,
+        proposedChanges: response.message.proposedChanges,
         conversationId: response.conversationId,
       };
       addMessage(botMessage);
       scrollToEnd();
     } catch (error) {
       console.error("Failed to send message:", error);
+    } finally {
+      // Hide typing indicator
+      clearTimeout(typingTimeoutRef.current);
+      setWaitingForResponse(false);
     }
   };
 
@@ -173,24 +246,46 @@ const Chat = () => {
             <ChatMessage
               side={item.side}
               content={item.content}
-              proposedChange={item.proposedChange}
+              proposedChanges={item.proposedChanges}
-              respondedAction={item.respondedAction}
+              onConfirm={(proposalId, proposal) =>
-              onConfirm={() =>
                 handleEventResponse(
                   "confirm",
                   item.id,
                   item.conversationId!,
-                  item.proposedChange,
+                  proposalId,
+                  proposal,
                 )
               }
-              onReject={() =>
+              onReject={(proposalId) =>
-                handleEventResponse("reject", item.id, item.conversationId!)
+                handleEventResponse(
+                  "reject",
+                  item.id,
+                  item.conversationId!,
+                  proposalId,
+                )
+              }
+              onEdit={(proposalId, proposal) =>
+                handleEditProposal(
+                  item.id,
+                  item.conversationId!,
+                  proposalId,
+                  proposal,
+                )
               }
             />
           )}
           keyExtractor={(item) => item.id}
           keyboardDismissMode="interactive"
           keyboardShouldPersistTaps="handled"
+          onContentSizeChange={() => {
+            if (needsInitialScroll.current) {
+              needsInitialScroll.current = false;
+              listRef.current?.scrollToEnd({ animated: false });
+            }
+          }}
+          ListFooterComponent={
+            isWaitingForResponse ? <TypingIndicator /> : null
+          }
         />
         <ChatInput onSend={handleSend} />
       </KeyboardAvoidingView>
@@ -199,20 +294,23 @@ const Chat = () => {
 };
 
 const ChatHeader = () => {
+  const { theme } = useThemeStore();
   return (
     <Header className="flex flex-row items-center">
       <View
         className="ml-3 w-12 h-12 rounded-3xl border border-solid"
         style={{
-          backgroundColor: currentTheme.placeholderBg,
+          backgroundColor: theme.placeholderBg,
-          borderColor: currentTheme.primeFg,
+          borderColor: theme.primeFg,
         }}
       ></View>
-      <Text className="text-lg pl-3">CalChat</Text>
+      <Text className="text-lg pl-3" style={{ color: theme.textPrimary }}>
+        CalChat
+      </Text>
       <View
         className="h-2 bg-black"
         style={{
-          shadowColor: "#000",
+          shadowColor: theme.shadowColor,
           shadowOffset: {
             width: 0,
             height: 5,
@@ -231,6 +329,7 @@ const MIN_INPUT_HEIGHT = 40;
 const MAX_INPUT_HEIGHT = 150;
 
 const ChatInput = ({ onSend }: ChatInputProps) => {
+  const { theme } = useThemeStore();
   const [text, setText] = useState("");
 
   const handleSend = () => {
@@ -245,7 +344,8 @@ const ChatInput = ({ onSend }: ChatInputProps) => {
       <TextInput
         className="flex-1 border border-solid rounded-2xl px-3 py-2 mr-2"
         style={{
-          backgroundColor: currentTheme.messageBorderBg,
+          backgroundColor: theme.messageBorderBg,
+          color: theme.textPrimary,
           minHeight: MIN_INPUT_HEIGHT,
           maxHeight: MAX_INPUT_HEIGHT,
           textAlignVertical: "top",
@@ -253,14 +353,14 @@ const ChatInput = ({ onSend }: ChatInputProps) => {
         onChangeText={setText}
         value={text}
         placeholder="Nachricht..."
-        placeholderTextColor="#999"
+        placeholderTextColor={theme.textMuted}
         multiline
       />
       <Pressable onPress={handleSend}>
         <View
           className="w-10 h-10 rounded-full items-center justify-center"
           style={{
-            backgroundColor: currentTheme.placeholderBg,
+            backgroundColor: theme.placeholderBg,
           }}
         />
       </Pressable>
@@ -271,38 +371,92 @@ const ChatInput = ({ onSend }: ChatInputProps) => {
 const ChatMessage = ({
   side,
   content,
-  proposedChange,
+  proposedChanges,
-  respondedAction,
   onConfirm,
   onReject,
+  onEdit,
 }: ChatMessageProps) => {
-  const borderColor =
+  const { theme } = useThemeStore();
-    side === "left" ? currentTheme.chatBot : currentTheme.primeFg;
+  const [currentIndex, setCurrentIndex] = useState(0);
-  const selfSide =
+
-    side === "left"
+  const hasProposals = proposedChanges && proposedChanges.length > 0;
-      ? "self-start ml-2 rounded-bl-sm"
+  const hasMultiple = proposedChanges && proposedChanges.length > 1;
-      : "self-end mr-2 rounded-br-sm";
+  const currentProposal = proposedChanges?.[currentIndex];
+
+  const goToPrev = () => setCurrentIndex((i) => Math.max(0, i - 1));
+  const goToNext = () =>
+    setCurrentIndex((i) => Math.min((proposedChanges?.length || 1) - 1, i + 1));
+
+  const canGoPrev = currentIndex > 0;
+  const canGoNext = currentIndex < (proposedChanges?.length || 1) - 1;
 
   return (
-    <View
+    <ChatBubble
-      className={`bg-white border-2 border-solid rounded-xl my-2 ${selfSide}`}
+      side={side}
       style={{
-        borderColor: borderColor,
         maxWidth: "80%",
-        elevation: 8,
+        minWidth: hasProposals ? "75%" : undefined,
       }}
     >
-      <Text className="p-2">{content}</Text>
+      <Text className="p-2" style={{ color: theme.textPrimary }}>
+        {content}
+      </Text>
 
-      {proposedChange && onConfirm && onReject && (
+      {hasProposals && currentProposal && onConfirm && onReject && onEdit && (
-        <ProposedEventCard
+        <View>
-          proposedChange={proposedChange}
+          {/* Event card with optional navigation arrows */}
-          respondedAction={respondedAction}
+          <View className="flex-row items-center">
-          onConfirm={onConfirm}
+            {/* Left arrow */}
-          onReject={onReject}
+            {hasMultiple && (
-        />
+              <Pressable
+                onPress={goToPrev}
+                disabled={!canGoPrev}
+                className="p-1"
+                style={{ opacity: canGoPrev ? 1 : 0.3 }}
+              >
+                <Ionicons name="chevron-back" size={24} color={theme.primeFg} />
+              </Pressable>
+            )}
+
+            {/* Event Card */}
+            <View className="flex-1">
+              <ProposedEventCard
+                proposedChange={currentProposal}
+                onConfirm={(proposal) => onConfirm(proposal.id, proposal)}
+                onReject={() => onReject(currentProposal.id)}
+                onEdit={(proposal) => onEdit(proposal.id, proposal)}
+              />
+            </View>
+
+            {/* Right arrow */}
+            {hasMultiple && (
+              <Pressable
+                onPress={goToNext}
+                disabled={!canGoNext}
+                className="p-1"
+                style={{ opacity: canGoNext ? 1 : 0.3 }}
+              >
+                <Ionicons
+                  name="chevron-forward"
+                  size={24}
+                  color={theme.primeFg}
+                />
+              </Pressable>
+            )}
+          </View>
+
+          {/* Event counter */}
+          {hasMultiple && (
+            <Text
+              className="text-center text-sm pb-2"
+              style={{ color: theme.textSecondary || "#666" }}
+            >
+              Event {currentIndex + 1} von {proposedChanges.length}
+            </Text>
+          )}
+        </View>
       )}
-    </View>
+    </ChatBubble>
   );
 };
 

apps/client/src/app/(tabs)/settings.tsx

@@ -0,0 +1,251 @@
+import { ActivityIndicator, Text, View } from "react-native";
+import BaseBackground from "../../components/BaseBackground";
+import BaseButton, { BaseButtonProps } from "../../components/BaseButton";
+import { useThemeStore } from "../../stores/ThemeStore";
+import { AuthService } from "../../services/AuthService";
+import { router } from "expo-router";
+import { Ionicons } from "@expo/vector-icons";
+import { SimpleHeader } from "../../components/Header";
+import { THEMES } from "../../Themes";
+import CustomTextInput from "../../components/CustomTextInput";
+import { useCallback, useRef, useState } from "react";
+import { CaldavConfigService } from "../../services/CaldavConfigService";
+import { useCaldavConfigStore } from "../../stores";
+
+const handleLogout = async () => {
+  await AuthService.logout();
+  router.replace("/login");
+};
+
+const SettingsButton = (props: BaseButtonProps) => {
+  return (
+    <BaseButton
+      onPress={props.onPress}
+      solid={props.solid}
+      className={"w-11/12"}
+    >
+      {props.children}
+    </BaseButton>
+  );
+};
+
+type CaldavTextInputProps = {
+  title: string;
+  value: string;
+  onValueChange: (text: string) => void;
+  secureTextEntry?: boolean;
+};
+
+const CaldavTextInput = ({
+  title,
+  value,
+  onValueChange,
+  secureTextEntry,
+}: CaldavTextInputProps) => {
+  const { theme } = useThemeStore();
+  return (
+    <View className="flex flex-row items-center py-1">
+      <Text className="ml-4 w-24" style={{ color: theme.textPrimary }}>
+        {title}:
+      </Text>
+      <CustomTextInput
+        className="flex-1 mr-4 px-3 py-2"
+        text={value}
+        onValueChange={onValueChange}
+        secureTextEntry={secureTextEntry}
+      />
+    </View>
+  );
+};
+
+type Feedback = { text: string; isError: boolean; loading: boolean };
+
+const FeedbackRow = ({ feedback }: { feedback: Feedback | null }) => {
+  const { theme } = useThemeStore();
+  if (!feedback) return null;
+  return (
+    <View className="flex flex-row items-center justify-center mt-2 mx-4 gap-2">
+      {feedback.loading && (
+        <ActivityIndicator size="small" color={theme.textMuted} />
+      )}
+      <Text
+        style={{
+          color: feedback.loading
+            ? theme.textMuted
+            : feedback.isError
+              ? theme.rejectButton
+              : theme.confirmButton,
+        }}
+      >
+        {feedback.text}
+      </Text>
+    </View>
+  );
+};
+
+const CaldavSettings = () => {
+  const { theme } = useThemeStore();
+  const { config, setConfig } = useCaldavConfigStore();
+
+  const [serverUrl, setServerUrl] = useState(config?.serverUrl ?? "");
+  const [username, setUsername] = useState(config?.username ?? "");
+  const [password, setPassword] = useState(config?.password ?? "");
+  const [saveFeedback, setSaveFeedback] = useState<Feedback | null>(null);
+  const [syncFeedback, setSyncFeedback] = useState<Feedback | null>(null);
+  const saveTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const syncTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
+
+  const showFeedback = useCallback(
+    (
+      setter: typeof setSaveFeedback,
+      timer: typeof saveTimer,
+      text: string,
+      isError: boolean,
+      loading = false,
+    ) => {
+      if (timer.current) clearTimeout(timer.current);
+      setter({ text, isError, loading });
+      if (!loading) {
+        timer.current = setTimeout(() => setter(null), 3000);
+      }
+    },
+    [],
+  );
+
+  const saveConfig = async () => {
+    showFeedback(
+      setSaveFeedback,
+      saveTimer,
+      "Speichere Konfiguration...",
+      false,
+      true,
+    );
+    try {
+      const saved = await CaldavConfigService.saveConfig(
+        serverUrl,
+        username,
+        password,
+      );
+      setConfig(saved);
+      showFeedback(
+        setSaveFeedback,
+        saveTimer,
+        "Konfiguration wurde gespeichert",
+        false,
+      );
+    } catch {
+      showFeedback(
+        setSaveFeedback,
+        saveTimer,
+        "Fehler beim Speichern der Konfiguration",
+        true,
+      );
+    }
+  };
+
+  const sync = async () => {
+    showFeedback(setSyncFeedback, syncTimer, "Synchronisiere...", false, true);
+    try {
+      await CaldavConfigService.sync();
+      showFeedback(
+        setSyncFeedback,
+        syncTimer,
+        "Synchronisierung erfolgreich",
+        false,
+      );
+    } catch {
+      showFeedback(
+        setSyncFeedback,
+        syncTimer,
+        "Fehler beim Synchronisieren",
+        true,
+      );
+    }
+  };
+
+  return (
+    <>
+      <View>
+        <Text
+          className="text-center text-2xl"
+          style={{ color: theme.textPrimary }}
+        >
+          Caldav Config
+        </Text>
+      </View>
+      <View>
+        <View className="pb-1">
+          <CaldavTextInput
+            title="url"
+            value={serverUrl}
+            onValueChange={setServerUrl}
+          />
+          <CaldavTextInput
+            title="username"
+            value={username}
+            onValueChange={setUsername}
+          />
+          <CaldavTextInput
+            title="password"
+            value={password}
+            onValueChange={setPassword}
+            secureTextEntry
+          />
+        </View>
+        <View className="flex flex-row">
+          <BaseButton className="mx-4 w-1/5" solid={true} onPress={saveConfig}>
+            Save
+          </BaseButton>
+          <BaseButton className="w-1/5" solid={true} onPress={sync}>
+            Sync
+          </BaseButton>
+        </View>
+        <FeedbackRow feedback={saveFeedback} />
+        <FeedbackRow feedback={syncFeedback} />
+      </View>
+    </>
+  );
+};
+
+const Settings = () => {
+  const { theme, setTheme } = useThemeStore();
+
+  return (
+    <BaseBackground>
+      <SimpleHeader text="Settings" />
+      <View className="flex items-center mt-4">
+        <SettingsButton onPress={handleLogout} solid={true}>
+          <Ionicons name="log-out-outline" size={24} color={theme.primeFg} />{" "}
+          Logout
+        </SettingsButton>
+        <View>
+          <Text
+            className="text-center text-2xl"
+            style={{ color: theme.textPrimary }}
+          >
+            Select Theme
+          </Text>
+        </View>
+        <SettingsButton
+          solid={theme == THEMES.defaultLight}
+          onPress={() => {
+            setTheme("defaultLight");
+          }}
+        >
+          Default Light
+        </SettingsButton>
+        <SettingsButton
+          solid={theme == THEMES.defaultDark}
+          onPress={() => {
+            setTheme("defaultDark");
+          }}
+        >
+          Default Dark
+        </SettingsButton>
+      </View>
+      <CaldavSettings />
+    </BaseBackground>
+  );
+};
+
+export default Settings;

apps/client/src/app/_layout.tsx

@@ -7,8 +7,9 @@ export default function RootLayout() {
       <Stack.Screen name="(tabs)" />
       <Stack.Screen name="login" />
       <Stack.Screen name="register" />
-      <Stack.Screen name="event/[id]" />
+      <Stack.Screen name="editEvent" />
-      <Stack.Screen name="note/[id]" />
+      {/* <Stack.Screen name="event/[id]" /> */}
+      {/* <Stack.Screen name="note/[id]" /> */}
     </Stack>
   );
 }

apps/client/src/app/editEvent.tsx

@@ -0,0 +1,573 @@
+import {
+  View,
+  Text,
+  TextInput,
+  Pressable,
+  ActivityIndicator,
+} from "react-native";
+import { Frequency, rrulestr } from "rrule";
+import BaseBackground from "../components/BaseBackground";
+import { useThemeStore } from "../stores/ThemeStore";
+import { useCallback, useEffect, useState } from "react";
+import { router, useLocalSearchParams } from "expo-router";
+import Header, { HeaderButton } from "../components/Header";
+import {
+  DatePickerButton,
+  TimePickerButton,
+} from "../components/DateTimePicker";
+import { Ionicons } from "@expo/vector-icons";
+import { ScrollableDropdown } from "../components/ScrollableDropdown";
+import { useDropdownPosition } from "../hooks/useDropdownPosition";
+import { EventService, ChatService } from "../services";
+import {
+  buildRRule,
+  CreateEventDTO,
+  REPEAT_TYPE_LABELS,
+  RepeatType,
+} from "@calchat/shared";
+import { useChatStore } from "../stores";
+import CustomTextInput, {
+  CustomTextInputProps,
+} from "../components/CustomTextInput";
+
+type EditEventTextFieldProps = CustomTextInputProps & {
+  titel: string;
+};
+
+const EditEventTextField = (props: EditEventTextFieldProps) => {
+  const { theme } = useThemeStore();
+
+  return (
+    <View className={props.className}>
+      <Text className="text-xl" style={{ color: theme.textPrimary }}>
+        {props.titel}
+      </Text>
+      <CustomTextInput
+        className="flex-1 px-3 py-2"
+        text={props.text}
+        multiline={props.multiline}
+        onValueChange={props.onValueChange}
+      />
+    </View>
+  );
+};
+
+type PickerRowProps = {
+  title: string;
+  showLabels?: boolean;
+  dateValue: Date;
+  onDateChange: (date: Date) => void;
+  onTimeChange: (date: Date) => void;
+};
+
+const PickerRow = ({
+  showLabels,
+  dateValue,
+  title,
+  onDateChange,
+  onTimeChange,
+}: PickerRowProps) => {
+  const { theme } = useThemeStore();
+  return (
+    <View className="flex flex-row w-11/12 mt-4 items-end justify-between gap-x-2">
+      <Text className="text-xl pb-2" style={{ color: theme.textPrimary }}>
+        {title}
+      </Text>
+      <View className="flex flex-row w-10/12 gap-x-2">
+        <DatePickerButton
+          className="flex-1"
+          label={showLabels ? "Datum" : undefined}
+          value={dateValue}
+          onChange={onDateChange}
+        />
+        <TimePickerButton
+          className="flex-1"
+          label={showLabels ? "Uhrzeit" : undefined}
+          value={dateValue}
+          onChange={onTimeChange}
+        />
+      </View>
+    </View>
+  );
+};
+
+type RepeatPressableProps = {
+  focused: boolean;
+  repeatType: RepeatType;
+  setRepeatType: (repeatType: RepeatType) => void;
+};
+
+const RepeatPressable = ({
+  focused,
+  repeatType,
+  setRepeatType,
+}: RepeatPressableProps) => {
+  const { theme } = useThemeStore();
+  return (
+    <Pressable
+      className="px-4 py-2 rounded-lg border"
+      style={{
+        backgroundColor: focused ? theme.chatBot : theme.secondaryBg,
+        borderColor: theme.borderPrimary,
+      }}
+      onPress={() => setRepeatType(repeatType)}
+    >
+      <Text style={{ color: focused ? theme.buttonText : theme.textPrimary }}>
+        {repeatType}
+      </Text>
+    </Pressable>
+  );
+};
+
+type RepeatSelectorProps = {
+  repeatCount: number;
+  onRepeatCountChange: (count: number) => void;
+  repeatType: RepeatType;
+  onRepeatTypeChange: (type: RepeatType) => void;
+};
+
+// Static data for repeat count dropdown (1-120)
+const REPEAT_COUNT_DATA = Array.from({ length: 120 }, (_, i) => i + 1);
+
+const RepeatSelector = ({
+  repeatCount,
+  onRepeatCountChange,
+  repeatType,
+  onRepeatTypeChange,
+}: RepeatSelectorProps) => {
+  const { theme } = useThemeStore();
+  const dropdown = useDropdownPosition(2);
+
+  const handleSelectCount = useCallback(
+    (count: number) => {
+      onRepeatCountChange(count);
+      dropdown.close();
+    },
+    [onRepeatCountChange, dropdown],
+  );
+
+  const typeLabel = REPEAT_TYPE_LABELS[repeatType];
+
+  return (
+    <View className="mt-4">
+      {/* Repeat Type Selection */}
+      <View className="flex flex-row gap-2 mb-3">
+        <RepeatPressable
+          repeatType="Tag"
+          setRepeatType={onRepeatTypeChange}
+          focused={repeatType === "Tag"}
+        />
+        <RepeatPressable
+          repeatType="Woche"
+          setRepeatType={onRepeatTypeChange}
+          focused={repeatType === "Woche"}
+        />
+        <RepeatPressable
+          repeatType="Monat"
+          setRepeatType={onRepeatTypeChange}
+          focused={repeatType === "Monat"}
+        />
+        <RepeatPressable
+          repeatType="Jahr"
+          setRepeatType={onRepeatTypeChange}
+          focused={repeatType === "Jahr"}
+        />
+      </View>
+
+      {/* Repeat Count Selection */}
+      <View className="flex flex-row items-center">
+        <Text className="text-lg" style={{ color: theme.textPrimary }}>
+          Alle{" "}
+        </Text>
+        <Pressable
+          ref={dropdown.ref}
+          className="px-4 py-2 rounded-lg border"
+          style={{
+            backgroundColor: theme.secondaryBg,
+            borderColor: theme.borderPrimary,
+          }}
+          onPress={dropdown.open}
+        >
+          <Text className="text-lg" style={{ color: theme.textPrimary }}>
+            {repeatCount}
+          </Text>
+        </Pressable>
+        <Text className="text-lg" style={{ color: theme.textPrimary }}>
+          {" "}
+          {typeLabel}
+        </Text>
+      </View>
+
+      {/* Count Dropdown */}
+      <ScrollableDropdown
+        visible={dropdown.visible}
+        onClose={dropdown.close}
+        position={{
+          bottom: 12,
+          left: 10,
+          width: 100,
+        }}
+        data={REPEAT_COUNT_DATA}
+        keyExtractor={(n) => String(n)}
+        renderItem={(n, theme) => (
+          <View
+            className="w-full flex justify-center items-center py-2"
+            style={{
+              backgroundColor: n % 2 === 0 ? theme.primeBg : theme.secondaryBg,
+            }}
+          >
+            <Text className="text-xl" style={{ color: theme.textPrimary }}>
+              {n}
+            </Text>
+          </View>
+        )}
+        onSelect={handleSelectCount}
+        heightRatio={0.4}
+        initialScrollIndex={repeatCount - 1}
+      />
+    </View>
+  );
+};
+
+type EditEventHeaderProps = {
+  id?: string;
+  mode?: "calendar" | "chat";
+};
+
+const EditEventHeader = ({ id, mode }: EditEventHeaderProps) => {
+  const getTitle = () => {
+    if (mode === "chat") return "Edit Proposal";
+    return id ? "Edit Meeting" : "New Meeting";
+  };
+
+  return (
+    <Header className="flex flex-row justify-center items-center">
+      <HeaderButton
+        className="absolute left-6"
+        iconName="arrow-back-outline"
+        iconSize={36}
+        onPress={router.back}
+      />
+      <View className="h-full flex justify-center ml-4">
+        <Text className="text-center text-3xl font-bold">{getTitle()}</Text>
+      </View>
+    </Header>
+  );
+};
+
+type EditEventParams = {
+  id?: string;
+  date?: string;
+  mode?: "calendar" | "chat";
+  eventData?: string;
+  proposalContext?: string;
+};
+
+type ProposalContext = {
+  messageId: string;
+  proposalId: string;
+  conversationId: string;
+};
+
+const EditEventScreen = () => {
+  const { id, date, mode, eventData, proposalContext } =
+    useLocalSearchParams<EditEventParams>();
+  const { theme } = useThemeStore();
+  const updateMessage = useChatStore((state) => state.updateMessage);
+
+  // Only show loading if we need to fetch from API (calendar mode with id)
+  const [isLoading, setIsLoading] = useState(
+    mode !== "chat" && !!id && !eventData,
+  );
+
+  // Initialize dates from URL parameter or use current time
+  const initialDate = date ? new Date(date) : new Date();
+  const initialEndDate = new Date(initialDate.getTime() + 60 * 60 * 1000);
+
+  const [repeatVisible, setRepeatVisible] = useState(false);
+  const [repeatCount, setRepeatCount] = useState(1);
+  const [repeatType, setRepeatType] = useState<RepeatType>("Tag");
+  const [startDate, setStartDate] = useState(initialDate);
+  const [endDate, setEndDate] = useState(initialEndDate);
+  const [title, setTitle] = useState("");
+  const [description, setDescription] = useState("");
+
+  // Helper to populate form from event data
+  const populateFormFromEvent = useCallback((event: CreateEventDTO) => {
+    setStartDate(new Date(event.startTime));
+    setEndDate(new Date(event.endTime));
+    setTitle(event.title);
+    if (event.description) {
+      setDescription(event.description);
+    }
+
+    if (event.recurrenceRule) {
+      setRepeatVisible(true);
+
+      const rrule = rrulestr(event.recurrenceRule);
+      if (rrule.options.interval) {
+        setRepeatCount(rrule.options.interval);
+      }
+      switch (rrule.options.freq) {
+        case Frequency.DAILY:
+          setRepeatType("Tag");
+          break;
+        case Frequency.WEEKLY:
+          setRepeatType("Woche");
+          break;
+        case Frequency.MONTHLY:
+          setRepeatType("Monat");
+          break;
+        case Frequency.YEARLY:
+          setRepeatType("Jahr");
+          break;
+      }
+    }
+  }, []);
+
+  // Load event data based on mode
+  useEffect(() => {
+    // Chat mode: load from eventData JSON parameter
+    if (mode === "chat" && eventData) {
+      try {
+        const event = JSON.parse(eventData) as CreateEventDTO;
+        populateFormFromEvent(event);
+      } catch (error) {
+        console.error("Failed to parse eventData:", error);
+      }
+      return;
+    }
+
+    // Calendar mode with id: fetch from API
+    if (id && !eventData) {
+      const fetchEvent = async () => {
+        try {
+          const event = await EventService.getById(id);
+          populateFormFromEvent({
+            title: event.title,
+            description: event.description,
+            startTime: event.startTime,
+            endTime: event.endTime,
+            recurrenceRule: event.recurrenceRule,
+          });
+        } catch (error) {
+          console.error("Failed to load event: ", error);
+        } finally {
+          setIsLoading(false);
+        }
+      };
+
+      fetchEvent();
+    }
+  }, [id, mode, eventData, populateFormFromEvent]);
+
+  if (isLoading) {
+    return (
+      <BaseBackground>
+        <EditEventHeader id={id} mode={mode} />
+        <View className="flex-1 justify-center items-center">
+          <ActivityIndicator size="large" color={theme.chatBot} />
+        </View>
+      </BaseBackground>
+    );
+  }
+
+  const handleStartDateChange = (date: Date) => {
+    // Keep the time from startDate, update the date part
+    const newStart = new Date(startDate);
+    newStart.setFullYear(date.getFullYear(), date.getMonth(), date.getDate());
+    setStartDate(newStart);
+
+    // If end date is before new start date, adjust it
+    if (endDate < newStart) {
+      const newEnd = new Date(newStart);
+      newEnd.setHours(newStart.getHours() + 1);
+      setEndDate(newEnd);
+    }
+  };
+
+  const handleStartTimeChange = (date: Date) => {
+    // Keep the date from startDate, update the time part
+    const newStart = new Date(startDate);
+    newStart.setHours(date.getHours(), date.getMinutes(), 0, 0);
+    setStartDate(newStart);
+
+    // If end time is before new start time on the same day, adjust it
+    if (endDate <= newStart) {
+      const newEnd = new Date(newStart);
+      newEnd.setHours(newStart.getHours() + 1);
+      setEndDate(newEnd);
+    }
+  };
+
+  const handleEndDateChange = (date: Date) => {
+    // Keep the time from endDate, update the date part
+    const newEnd = new Date(endDate);
+    newEnd.setFullYear(date.getFullYear(), date.getMonth(), date.getDate());
+    setEndDate(newEnd);
+  };
+
+  const handleEndTimeChange = (date: Date) => {
+    // Keep the date from endDate, update the time part
+    const newEnd = new Date(endDate);
+    newEnd.setHours(date.getHours(), date.getMinutes(), 0, 0);
+    setEndDate(newEnd);
+  };
+
+  const handleSave = async () => {
+    const eventObject: CreateEventDTO = {
+      title,
+      description: description === "" ? undefined : description,
+      startTime: startDate,
+      endTime: endDate,
+      recurrenceRule: repeatVisible
+        ? buildRRule(repeatType, repeatCount)
+        : undefined,
+    };
+
+    // Chat mode: update proposal on server and sync response to local store
+    if (mode === "chat" && proposalContext) {
+      try {
+        const context = JSON.parse(proposalContext) as ProposalContext;
+
+        // Persist to server - returns updated message with recalculated conflictingEvents
+        const updatedMessage = await ChatService.updateProposalEvent(
+          context.messageId,
+          context.proposalId,
+          eventObject,
+        );
+
+        // Update local ChatStore with server response (includes updated conflicts)
+        if (updatedMessage?.proposedChanges) {
+          updateMessage(context.messageId, {
+            proposedChanges: updatedMessage.proposedChanges,
+          });
+        }
+
+        router.back();
+      } catch (error) {
+        console.error("Failed to update proposal:", error);
+      }
+      return;
+    }
+
+    // Calendar mode: call API
+    try {
+      if (id) {
+        await EventService.update(id, eventObject);
+      } else {
+        await EventService.create(eventObject);
+      }
+      router.back();
+    } catch (error) {
+      console.error("Creating/Updating event failed!", error);
+    }
+  };
+
+  const getButtonText = () => {
+    if (mode === "chat") {
+      return "Fertig";
+    }
+    return id ? "Aktualisiere Termin" : "Erstelle neuen Termin";
+  };
+
+  return (
+    <BaseBackground>
+      <EditEventHeader id={id} mode={mode} />
+      <View className="h-full flex items-center">
+        {/* Date and Time */}
+        <View className="w-11/12">
+          <EditEventTextField
+            className="h-16 mt-2"
+            titel="Titel"
+            text={title}
+            onValueChange={setTitle}
+          />
+          <PickerRow
+            title="Von"
+            dateValue={startDate}
+            onDateChange={handleStartDateChange}
+            onTimeChange={handleStartTimeChange}
+            showLabels
+          />
+          <PickerRow
+            title="Bis"
+            dateValue={endDate}
+            onDateChange={handleEndDateChange}
+            onTimeChange={handleEndTimeChange}
+          />
+
+          {/* TODO: Reminder */}
+
+          {/* Notes */}
+          <EditEventTextField
+            className="h-64 mt-6"
+            titel="Notizen"
+            text={description}
+            onValueChange={setDescription}
+            multiline
+          />
+
+          {/* Repeat Toggle Button */}
+          <Pressable
+            className="flex flex-row w-1/3 h-10 mt-4 rounded-lg items-center justify-evenly"
+            style={{
+              backgroundColor: repeatVisible
+                ? theme.chatBot
+                : theme.secondaryBg,
+              borderWidth: 1,
+              borderColor: theme.borderPrimary,
+            }}
+            onPress={() => setRepeatVisible(!repeatVisible)}
+          >
+            <Ionicons
+              name="repeat"
+              size={24}
+              color={repeatVisible ? theme.buttonText : theme.textPrimary}
+            />
+            <Text
+              style={{
+                color: repeatVisible ? theme.buttonText : theme.textPrimary,
+              }}
+            >
+              Wiederholen
+            </Text>
+          </Pressable>
+
+          {/* Repeat Selector (shown when toggle is active) */}
+          {repeatVisible && (
+            <RepeatSelector
+              repeatCount={repeatCount}
+              onRepeatCountChange={setRepeatCount}
+              repeatType={repeatType}
+              onRepeatTypeChange={setRepeatType}
+            />
+          )}
+        </View>
+      </View>
+
+      {/* Send new or updated Event */}
+      <View className="absolute bottom-16 w-full h-16">
+        <Pressable
+          className="flex flex-row justify-center items-center py-3"
+          onPress={handleSave}
+          style={{
+            backgroundColor: theme.confirmButton,
+          }}
+        >
+          {mode !== "chat" && (
+            <Ionicons name="add-outline" size={24} color={theme.buttonText} />
+          )}
+          <Text
+            style={{ color: theme.buttonText }}
+            className="font-semibold ml-1"
+          >
+            {getButtonText()}
+          </Text>
+        </Pressable>
+      </View>
+    </BaseBackground>
+  );
+};
+
+export default EditEventScreen;

apps/client/src/app/event/[id].tsx

@@ -1,9 +1,11 @@
 import { View, Text, TextInput, Pressable } from "react-native";
 import { useLocalSearchParams } from "expo-router";
 import BaseBackground from "../../components/BaseBackground";
+import { useThemeStore } from "../../stores/ThemeStore";
 
 const EventDetailScreen = () => {
   const { id } = useLocalSearchParams<{ id: string }>();
+  const { theme } = useThemeStore();
 
   // TODO: Fetch event by id using EventService.getById()
   // TODO: Display event details (title, description, start/end time)
@@ -17,23 +19,49 @@ const EventDetailScreen = () => {
   return (
     <BaseBackground>
       <View className="flex-1 p-4">
-        <Text className="text-2xl mb-4">Event Detail</Text>
+        <Text className="text-2xl mb-4" style={{ color: theme.textPrimary }}>
-        <Text className="text-gray-500 mb-4">ID: {id}</Text>
+          Event Detail
+        </Text>
+        <Text className="mb-4" style={{ color: theme.textSecondary }}>
+          ID: {id}
+        </Text>
         <TextInput
           placeholder="Title"
+          placeholderTextColor={theme.textMuted}
           className="w-full border rounded p-2 mb-4"
+          style={{
+            color: theme.textPrimary,
+            borderColor: theme.borderPrimary,
+            backgroundColor: theme.secondaryBg,
+          }}
         />
         <TextInput
           placeholder="Description"
+          placeholderTextColor={theme.textMuted}
           multiline
           className="w-full border rounded p-2 mb-4 h-24"
+          style={{
+            color: theme.textPrimary,
+            borderColor: theme.borderPrimary,
+            backgroundColor: theme.secondaryBg,
+          }}
         />
         <View className="flex-row gap-2">
-          <Pressable className="bg-blue-500 p-3 rounded flex-1">
+          <Pressable
-            <Text className="text-white text-center">Save</Text>
+            className="p-3 rounded flex-1"
+            style={{ backgroundColor: theme.confirmButton }}
+          >
+            <Text className="text-center" style={{ color: theme.buttonText }}>
+              Save
+            </Text>
           </Pressable>
-          <Pressable className="bg-red-500 p-3 rounded flex-1">
+          <Pressable
-            <Text className="text-white text-center">Delete</Text>
+            className="p-3 rounded flex-1"
+            style={{ backgroundColor: theme.rejectButton }}
+          >
+            <Text className="text-center" style={{ color: theme.buttonText }}>
+              Delete
+            </Text>
           </Pressable>
         </View>
       </View>

apps/client/src/app/index.tsx

@@ -1,5 +1,6 @@
 import { Redirect } from "expo-router";
 
 export default function Index() {
+  // AuthGuard in (tabs)/_layout.tsx handles authentication
   return <Redirect href="/(tabs)/chat" />;
 }

apps/client/src/app/login.tsx

@@ -1,31 +1,96 @@
-import { View, Text, TextInput, Pressable } from "react-native";
+import { useState } from "react";
+import { View, Text, Pressable } from "react-native";
+import { Link, router } from "expo-router";
 import BaseBackground from "../components/BaseBackground";
+import AuthButton from "../components/AuthButton";
+import CustomTextInput from "../components/CustomTextInput";
+import { AuthService } from "../services";
+import { CaldavConfigService } from "../services/CaldavConfigService";
+import { preloadAppData } from "../components/AuthGuard";
+import { useThemeStore } from "../stores/ThemeStore";
 
 const LoginScreen = () => {
-  // TODO: Email input field
+  const { theme } = useThemeStore();
-  // TODO: Password input field
+  const [identifier, setIdentifier] = useState("");
-  // TODO: Login button -> AuthService.login()
+  const [password, setPassword] = useState("");
-  // TODO: Link to RegisterScreen
+  const [error, setError] = useState<string | null>(null);
-  // TODO: Error handling and display
+  const [isLoading, setIsLoading] = useState(false);
-  // TODO: Navigate to Calendar on success
+
-  throw new Error("Not implemented");
+  const handleLogin = async () => {
+    setError(null);
+
+    if (!identifier || !password) {
+      setError("Bitte alle Felder ausfüllen");
+      return;
+    }
+
+    setIsLoading(true);
+    try {
+      await AuthService.login({ identifier, password });
+      await preloadAppData();
+      try {
+        await CaldavConfigService.sync();
+      } catch {
+        // No CalDAV config or sync failed — not critical
+      }
+      router.replace("/(tabs)/chat");
+    } catch {
+      setError("Anmeldung fehlgeschlagen. Überprüfe deine Zugangsdaten.");
+    } finally {
+      setIsLoading(false);
+    }
+  };
 
   return (
     <BaseBackground>
-      <View className="flex-1 justify-center items-center p-4">
+      <View className="flex-1 justify-center items-center p-8">
-        <Text className="text-2xl mb-8">Login</Text>
+        <Text
-        <TextInput
+          className="text-3xl font-bold mb-8"
-          placeholder="Email"
+          style={{ color: theme.textPrimary }}
-          className="w-full border rounded p-2 mb-4"
+        >
+          Anmelden
+        </Text>
+
+        {error && (
+          <Text
+            className="mb-4 text-center"
+            style={{ color: theme.rejectButton }}
+          >
+            {error}
+          </Text>
+        )}
+
+        <CustomTextInput
+          placeholder="E-Mail oder Benutzername"
+          placeholderTextColor={theme.textMuted}
+          text={identifier}
+          onValueChange={setIdentifier}
+          autoCapitalize="none"
+          className="w-full rounded-lg p-4 mb-4"
         />
-        <TextInput
+
-          placeholder="Password"
+        <CustomTextInput
+          placeholder="Passwort"
+          placeholderTextColor={theme.textMuted}
+          text={password}
+          onValueChange={setPassword}
           secureTextEntry
-          className="w-full border rounded p-2 mb-4"
+          className="w-full rounded-lg p-4 mb-6"
         />
-        <Pressable className="bg-blue-500 p-3 rounded w-full">
+
-          <Text className="text-white text-center">Login</Text>
+        <AuthButton
-        </Pressable>
+          title="Anmelden"
+          onPress={handleLogin}
+          isLoading={isLoading}
+        />
+
+        <Link href="/register" asChild>
+          <Pressable>
+            <Text style={{ color: theme.chatBot }}>
+              Noch kein Konto? Registrieren
+            </Text>
+          </Pressable>
+        </Link>
       </View>
     </BaseBackground>
   );

apps/client/src/app/note/[id].tsx

@@ -1,9 +1,11 @@
 import { View, Text, TextInput, Pressable } from "react-native";
 import { useLocalSearchParams } from "expo-router";
 import BaseBackground from "../../components/BaseBackground";
+import { useThemeStore } from "../../stores/ThemeStore";
 
 const NoteScreen = () => {
   const { id } = useLocalSearchParams<{ id: string }>();
+  const { theme } = useThemeStore();
 
   // TODO: Fetch event by id using EventService.getById()
   // TODO: Display and edit the event's note field
@@ -15,16 +17,31 @@ const NoteScreen = () => {
   return (
     <BaseBackground>
       <View className="flex-1 p-4">
-        <Text className="text-2xl mb-4">Note</Text>
+        <Text className="text-2xl mb-4" style={{ color: theme.textPrimary }}>
-        <Text className="text-gray-500 mb-4">Event ID: {id}</Text>
+          Note
+        </Text>
+        <Text className="mb-4" style={{ color: theme.textSecondary }}>
+          Event ID: {id}
+        </Text>
         <TextInput
           placeholder="Write your note here..."
+          placeholderTextColor={theme.textMuted}
           multiline
           className="w-full border rounded p-2 flex-1 mb-4"
           textAlignVertical="top"
+          style={{
+            color: theme.textPrimary,
+            borderColor: theme.borderPrimary,
+            backgroundColor: theme.secondaryBg,
+          }}
         />
-        <Pressable className="bg-blue-500 p-3 rounded">
+        <Pressable
-          <Text className="text-white text-center">Save Note</Text>
+          className="p-3 rounded"
+          style={{ backgroundColor: theme.confirmButton }}
+        >
+          <Text className="text-center" style={{ color: theme.buttonText }}>
+            Save Note
+          </Text>
         </Pressable>
       </View>
     </BaseBackground>

apps/client/src/app/register.tsx

@@ -1,42 +1,106 @@
-import { View, Text, TextInput, Pressable } from "react-native";
+import { useState } from "react";
+import { View, Text, Pressable } from "react-native";
+import { Link, router } from "expo-router";
 import BaseBackground from "../components/BaseBackground";
+import AuthButton from "../components/AuthButton";
+import CustomTextInput from "../components/CustomTextInput";
+import { AuthService } from "../services";
+import { useThemeStore } from "../stores/ThemeStore";
+
+const EMAIL_REGEX = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
 
 const RegisterScreen = () => {
-  // TODO: Email input field
+  const { theme } = useThemeStore();
-  // TODO: Display name input field
+  const [email, setEmail] = useState("");
-  // TODO: Password input field
+  const [userName, setUserName] = useState("");
-  // TODO: Password confirmation field
+  const [password, setPassword] = useState("");
-  // TODO: Register button -> AuthService.register()
+  const [error, setError] = useState<string | null>(null);
-  // TODO: Link to LoginScreen
+  const [isLoading, setIsLoading] = useState(false);
-  // TODO: Error handling and display
+
-  // TODO: Navigate to Calendar on success
+  const handleRegister = async () => {
-  throw new Error("Not implemented");
+    setError(null);
+
+    if (!email || !userName || !password) {
+      setError("Bitte alle Felder ausfüllen");
+      return;
+    }
+
+    if (!EMAIL_REGEX.test(email)) {
+      setError("Bitte eine gültige E-Mail-Adresse eingeben");
+      return;
+    }
+
+    setIsLoading(true);
+    try {
+      await AuthService.register({ email, userName, password });
+      router.replace("/(tabs)/chat");
+    } catch {
+      setError("Registrierung fehlgeschlagen. E-Mail bereits vergeben?");
+    } finally {
+      setIsLoading(false);
+    }
+  };
 
   return (
     <BaseBackground>
-      <View className="flex-1 justify-center items-center p-4">
+      <View className="flex-1 justify-center items-center p-8">
-        <Text className="text-2xl mb-8">Register</Text>
+        <Text
-        <TextInput
+          className="text-3xl font-bold mb-8"
-          placeholder="Email"
+          style={{ color: theme.textPrimary }}
-          className="w-full border rounded p-2 mb-4"
+        >
+          Registrieren
+        </Text>
+
+        {error && (
+          <Text
+            className="mb-4 text-center"
+            style={{ color: theme.rejectButton }}
+          >
+            {error}
+          </Text>
+        )}
+
+        <CustomTextInput
+          placeholder="E-Mail"
+          placeholderTextColor={theme.textMuted}
+          text={email}
+          onValueChange={setEmail}
+          autoCapitalize="none"
+          keyboardType="email-address"
+          className="w-full rounded-lg p-4 mb-4"
         />
-        <TextInput
+
-          placeholder="Display Name"
+        <CustomTextInput
-          className="w-full border rounded p-2 mb-4"
+          placeholder="Benutzername"
+          placeholderTextColor={theme.textMuted}
+          text={userName}
+          onValueChange={setUserName}
+          autoCapitalize="none"
+          className="w-full rounded-lg p-4 mb-4"
         />
-        <TextInput
+
-          placeholder="Password"
+        <CustomTextInput
+          placeholder="Passwort"
+          placeholderTextColor={theme.textMuted}
+          text={password}
+          onValueChange={setPassword}
           secureTextEntry
-          className="w-full border rounded p-2 mb-4"
+          className="w-full rounded-lg p-4 mb-6"
         />
-        <TextInput
+
-          placeholder="Confirm Password"
+        <AuthButton
-          secureTextEntry
+          title="Registrieren"
-          className="w-full border rounded p-2 mb-4"
+          onPress={handleRegister}
+          isLoading={isLoading}
         />
-        <Pressable className="bg-blue-500 p-3 rounded w-full">
+
-          <Text className="text-white text-center">Register</Text>
+        <Link href="/login" asChild>
-        </Pressable>
+          <Pressable>
+            <Text style={{ color: theme.chatBot }}>
+              Bereits ein Konto? Anmelden
+            </Text>
+          </Pressable>
+        </Link>
       </View>
     </BaseBackground>
   );

apps/client/src/components/AuthButton.tsx

@@ -0,0 +1,40 @@
+import { Pressable, Text, ActivityIndicator } from "react-native";
+import { useThemeStore } from "../stores/ThemeStore";
+
+interface AuthButtonProps {
+  title: string;
+  onPress: () => void;
+  isLoading?: boolean;
+}
+
+const AuthButton = ({ title, onPress, isLoading = false }: AuthButtonProps) => {
+  const { theme } = useThemeStore();
+  return (
+    <Pressable
+      onPress={onPress}
+      disabled={isLoading}
+      className="w-full rounded-lg p-4 mb-4 border-4"
+      style={{
+        backgroundColor: isLoading ? theme.disabledButton : theme.chatBot,
+        shadowColor: theme.shadowColor,
+        shadowOffset: { width: 0, height: 2 },
+        shadowOpacity: 0.25,
+        shadowRadius: 3.84,
+        elevation: 5,
+      }}
+    >
+      {isLoading ? (
+        <ActivityIndicator color={theme.buttonText} />
+      ) : (
+        <Text
+          className="text-center font-semibold text-lg"
+          style={{ color: theme.buttonText }}
+        >
+          {title}
+        </Text>
+      )}
+    </Pressable>
+  );
+};
+
+export default AuthButton;

apps/client/src/components/AuthGuard.tsx

@@ -0,0 +1,89 @@
+import { useEffect, useState, ReactNode } from "react";
+import { View, ActivityIndicator } from "react-native";
+import { Redirect } from "expo-router";
+import { useAuthStore } from "../stores";
+import { useThemeStore } from "../stores/ThemeStore";
+import { useEventsStore } from "../stores/EventsStore";
+import { useCaldavConfigStore } from "../stores/CaldavConfigStore";
+import { EventService } from "../services";
+import { CaldavConfigService } from "../services/CaldavConfigService";
+
+type AuthGuardProps = {
+  children: ReactNode;
+};
+
+/**
+ * Preloads app data (events + CalDAV config) into stores.
+ * Called before the loading spinner is dismissed so screens have data immediately.
+ */
+export const preloadAppData = async () => {
+  const now = new Date();
+  const firstOfMonth = new Date(now.getFullYear(), now.getMonth(), 1);
+  const dayOfWeek = firstOfMonth.getDay();
+  const daysFromPrevMonth = dayOfWeek === 0 ? 6 : dayOfWeek - 1;
+  const startDate = new Date(
+    now.getFullYear(),
+    now.getMonth(),
+    1 - daysFromPrevMonth,
+  );
+  const endDate = new Date(startDate);
+  endDate.setDate(startDate.getDate() + 41);
+  endDate.setHours(23, 59, 59);
+
+  const [eventsResult, configResult] = await Promise.allSettled([
+    EventService.getByDateRange(startDate, endDate),
+    CaldavConfigService.getConfig(),
+  ]);
+
+  if (eventsResult.status === "fulfilled") {
+    useEventsStore.getState().setEvents(eventsResult.value);
+  }
+  if (configResult.status === "fulfilled") {
+    useCaldavConfigStore.getState().setConfig(configResult.value);
+  }
+};
+
+/**
+ * Wraps content that requires authentication.
+ * - Loads stored user on mount
+ * - Preloads app data (events, CalDAV config) before dismissing spinner
+ * - Shows loading indicator while checking auth state
+ * - Redirects to login if not authenticated
+ * - Renders children if authenticated
+ */
+export const AuthGuard = ({ children }: AuthGuardProps) => {
+  const { theme } = useThemeStore();
+  const { isAuthenticated, isLoading, loadStoredUser } = useAuthStore();
+  const [dataReady, setDataReady] = useState(false);
+
+  useEffect(() => {
+    const init = async () => {
+      await loadStoredUser();
+      if (!useAuthStore.getState().isAuthenticated) return;
+      await preloadAppData();
+      setDataReady(true);
+    };
+    init();
+  }, [loadStoredUser]);
+
+  if (isLoading || (isAuthenticated && !dataReady)) {
+    return (
+      <View
+        style={{
+          flex: 1,
+          justifyContent: "center",
+          alignItems: "center",
+          backgroundColor: theme.primeBg,
+        }}
+      >
+        <ActivityIndicator size="large" color={theme.chatBot} />
+      </View>
+    );
+  }
+
+  if (!isAuthenticated) {
+    return <Redirect href="/login" />;
+  }
+
+  return <>{children}</>;
+};

apps/client/src/components/BaseBackground.tsx

@@ -1,5 +1,5 @@
 import { View } from "react-native";
-import currentTheme from "../Themes";
+import { useThemeStore } from "../stores/ThemeStore";
 import { ReactNode } from "react";
 
 type BaseBackgroundProps = {
@@ -8,11 +8,12 @@ type BaseBackgroundProps = {
 };
 
 const BaseBackground = (props: BaseBackgroundProps) => {
+  const { theme } = useThemeStore();
   return (
     <View
       className={`h-full ${props.className}`}
       style={{
-        backgroundColor: currentTheme.primeBg,
+        backgroundColor: theme.primeBg,
       }}
     >
       {props.children}

apps/client/src/components/BaseButton.tsx

@@ -0,0 +1,43 @@
+import { Pressable, Text } from "react-native";
+import { useThemeStore } from "../stores/ThemeStore";
+import { ReactNode } from "react";
+
+export type BaseButtonProps = {
+  children?: ReactNode;
+  className?: string;
+  onPress: () => void;
+  solid?: boolean;
+};
+
+const BaseButton = ({
+  className,
+  children,
+  onPress,
+  solid = false,
+}: BaseButtonProps) => {
+  const { theme } = useThemeStore();
+  return (
+    <Pressable
+      className={`rounded-lg p-4 mb-4 border-4 ${className}`}
+      onPress={onPress}
+      style={{
+        borderColor: theme.borderPrimary,
+        backgroundColor: solid ? theme.chatBot : theme.primeBg,
+        shadowColor: theme.shadowColor,
+        shadowOffset: { width: 0, height: 2 },
+        shadowOpacity: 0.25,
+        shadowRadius: 3.84,
+        elevation: 5,
+      }}
+    >
+      <Text
+        className="text-center font-semibold text-lg"
+        style={{ color: theme.buttonText }}
+      >
+        {children}
+      </Text>
+    </Pressable>
+  );
+};
+
+export default BaseButton;

apps/client/src/components/CardBase.tsx

@@ -0,0 +1,120 @@
+import { View, Text, Pressable, ScrollView } from "react-native";
+import { ReactNode } from "react";
+import { useThemeStore } from "../stores/ThemeStore";
+
+type TextSize = "text-sm" | "text-base" | "text-lg" | "text-xl";
+
+type CardBaseProps = {
+  title: string;
+  subtitle?: string;
+  children: ReactNode;
+  attachment?: ReactNode; // renders between children and footer
+  footer?: {
+    label: string;
+    onPress: () => void;
+  };
+  className?: string;
+  scrollable?: boolean;
+  maxContentHeight?: number;
+  borderWidth?: number;
+  headerBorderWidth?: number;
+  headerPadding?: number;
+  contentPadding?: number;
+  headerTextSize?: TextSize;
+  contentBg?: string;
+};
+
+export const CardBase = ({
+  title,
+  subtitle,
+  children,
+  attachment,
+  footer,
+  className = "",
+  scrollable = false,
+  maxContentHeight,
+  borderWidth = 2,
+  headerBorderWidth,
+  headerPadding,
+  contentPadding,
+  headerTextSize = "text-base",
+  contentBg,
+}: CardBaseProps) => {
+  const { theme } = useThemeStore();
+  const effectiveHeaderBorderWidth = headerBorderWidth ?? borderWidth;
+
+  const headerPaddingClass = headerPadding ? `p-${headerPadding}` : "px-3 py-2";
+  const contentPaddingClass = contentPadding
+    ? `p-${contentPadding}`
+    : "px-3 py-2";
+
+  const contentElement = (
+    <View
+      className={contentPaddingClass}
+      style={{ backgroundColor: contentBg ?? theme.secondaryBg }}
+    >
+      {children}
+    </View>
+  );
+
+  return (
+    <View
+      className={`rounded-xl overflow-hidden ${className}`}
+      style={{ borderWidth, borderColor: theme.borderPrimary }}
+    >
+      {/* Header */}
+      <View
+        className={headerPaddingClass}
+        style={{
+          backgroundColor: theme.chatBot,
+          borderBottomWidth: effectiveHeaderBorderWidth,
+          borderBottomColor: theme.borderPrimary,
+        }}
+      >
+        <Text
+          className={`font-bold ${headerTextSize}`}
+          style={{ color: theme.textPrimary }}
+        >
+          {title}
+        </Text>
+        {subtitle && (
+          <Text style={{ color: theme.primeFg }} numberOfLines={1}>
+            {subtitle}
+          </Text>
+        )}
+      </View>
+
+      {/* Content */}
+      {scrollable ? (
+        <ScrollView
+          style={{ maxHeight: maxContentHeight }}
+          nestedScrollEnabled={true}
+        >
+          {contentElement}
+        </ScrollView>
+      ) : (
+        contentElement
+      )}
+
+      {attachment}
+
+      {/* Footer (optional) */}
+      {footer && (
+        <Pressable
+          onPress={footer.onPress}
+          className="py-3 items-center"
+          style={{
+            borderTopWidth: 1,
+            borderTopColor: theme.placeholderBg,
+          }}
+        >
+          <Text style={{ color: theme.primeFg }} className="font-bold">
+            {footer.label}
+          </Text>
+        </Pressable>
+      )}
+    </View>
+  );
+};
+
+export default CardBase;

apps/client/src/components/ChatBubble.tsx

@@ -0,0 +1,37 @@
+import { View, ViewStyle } from "react-native";
+import { useThemeStore } from "../stores/ThemeStore";
+
+type BubbleSide = "left" | "right";
+
+type ChatBubbleProps = {
+  side: BubbleSide;
+  children: React.ReactNode;
+  className?: string;
+  style?: ViewStyle;
+};
+
+export function ChatBubble({
+  side,
+  children,
+  className = "",
+  style,
+}: ChatBubbleProps) {
+  const { theme } = useThemeStore();
+  const borderColor = side === "left" ? theme.chatBot : theme.primeFg;
+  const sideClass =
+    side === "left"
+      ? "self-start ml-2 rounded-bl-sm"
+      : "self-end mr-2 rounded-br-sm";
+
+  return (
+    <View
+      className={`border-2 border-solid rounded-xl my-2 ${sideClass} ${className}`}
+      style={[
+        { borderColor, elevation: 8, backgroundColor: theme.secondaryBg },
+        style,
+      ]}
+    >
+      {children}
+    </View>
+  );
+}

apps/client/src/components/CustomTextInput.tsx

@@ -0,0 +1,46 @@
+import { TextInput, TextInputProps } from "react-native";
+import { useThemeStore } from "../stores/ThemeStore";
+import { useState } from "react";
+
+export type CustomTextInputProps = {
+  text?: string;
+  focused?: boolean;
+  className?: string;
+  multiline?: boolean;
+  onValueChange?: (text: string) => void;
+  placeholder?: string;
+  placeholderTextColor?: string;
+  secureTextEntry?: boolean;
+  autoCapitalize?: TextInputProps["autoCapitalize"];
+  keyboardType?: TextInputProps["keyboardType"];
+};
+
+const CustomTextInput = (props: CustomTextInputProps) => {
+  const { theme } = useThemeStore();
+  const [focused, setFocused] = useState(props.focused ?? false);
+
+  return (
+    <TextInput
+      className={`border border-solid rounded-2xl ${props.className}`}
+      onChangeText={props.onValueChange}
+      value={props.text}
+      multiline={props.multiline}
+      placeholder={props.placeholder}
+      placeholderTextColor={props.placeholderTextColor}
+      secureTextEntry={props.secureTextEntry}
+      autoCapitalize={props.autoCapitalize}
+      keyboardType={props.keyboardType}
+      selection={!focused ? { start: 0 } : undefined}
+      style={{
+        backgroundColor: theme.messageBorderBg,
+        color: theme.textPrimary,
+        textAlignVertical: "top",
+        borderColor: focused ? theme.chatBot : theme.borderPrimary,
+      }}
+      onFocus={() => setFocused(true)}
+      onBlur={() => setFocused(false)}
+    />
+  );
+};
+
+export default CustomTextInput;

apps/client/src/components/DateTimePicker.tsx

@@ -0,0 +1,136 @@
+import { useState } from "react";
+import { Platform, Modal, Pressable, Text, View } from "react-native";
+import DateTimePicker, {
+  DateTimePickerEvent,
+} from "@react-native-community/datetimepicker";
+import { useThemeStore } from "../stores/ThemeStore";
+import { THEMES } from "../Themes";
+
+type DateTimePickerButtonProps = {
+  mode: "date" | "time";
+  className?: string;
+  label?: string;
+  value: Date;
+  onChange: (date: Date) => void;
+};
+
+const DateTimePickerButton = ({
+  mode,
+  label,
+  value,
+  onChange,
+  className,
+}: DateTimePickerButtonProps) => {
+  const { theme } = useThemeStore();
+  const [showPicker, setShowPicker] = useState(false);
+  const isDark = theme === THEMES.defaultDark;
+
+  const handleChange = (event: DateTimePickerEvent, selectedDate?: Date) => {
+    if (Platform.OS === "android") {
+      setShowPicker(false);
+    }
+    if (event.type === "set" && selectedDate) {
+      onChange(selectedDate);
+    }
+  };
+
+  const formattedValue =
+    mode === "date"
+      ? value.toLocaleDateString("de-DE", {
+          day: "2-digit",
+          month: "2-digit",
+          year: "numeric",
+        })
+      : value.toLocaleTimeString("de-DE", {
+          hour: "2-digit",
+          minute: "2-digit",
+        });
+
+  return (
+    <View className={className}>
+      {label && (
+        <Text style={{ color: theme.textSecondary }} className="text-sm mb-1">
+          {label}
+        </Text>
+      )}
+      <Pressable
+        onPress={() => setShowPicker(true)}
+        className="w-full rounded-lg px-3 py-2 border"
+        style={{
+          backgroundColor: theme.messageBorderBg,
+          borderColor: theme.borderPrimary,
+        }}
+      >
+        <Text style={{ color: theme.textPrimary }} className="text-base">
+          {formattedValue}
+        </Text>
+      </Pressable>
+
+      {Platform.OS === "ios" ? (
+        <Modal
+          visible={showPicker}
+          transparent
+          animationType="fade"
+          onRequestClose={() => setShowPicker(false)}
+        >
+          <Pressable
+            className="flex-1 justify-end"
+            style={{ backgroundColor: "rgba(0,0,0,0.5)" }}
+            onPress={() => setShowPicker(false)}
+          >
+            <View
+              style={{ backgroundColor: theme.secondaryBg }}
+              className="rounded-t-2xl"
+            >
+              <View className="flex-row justify-end p-2">
+                <Pressable onPress={() => setShowPicker(false)} className="p-2">
+                  <Text
+                    style={{ color: theme.chatBot }}
+                    className="text-lg font-semibold"
+                  >
+                    Fertig
+                  </Text>
+                </Pressable>
+              </View>
+              <DateTimePicker
+                value={value}
+                mode={mode}
+                display="spinner"
+                onChange={handleChange}
+                locale="de-DE"
+                is24Hour={mode === "time"}
+                accentColor={theme.chatBot}
+                textColor={theme.textPrimary}
+                themeVariant={isDark ? "dark" : "light"}
+              />
+            </View>
+          </Pressable>
+        </Modal>
+      ) : (
+        showPicker && (
+          <DateTimePicker
+            value={value}
+            mode={mode}
+            display="default"
+            onChange={handleChange}
+            is24Hour={mode === "time"}
+            accentColor={theme.chatBot}
+            textColor={theme.textPrimary}
+            themeVariant={isDark ? "dark" : "light"}
+          />
+        )
+      )}
+    </View>
+  );
+};
+
+// Convenience wrappers for simpler usage
+export const DatePickerButton = (
+  props: Omit<DateTimePickerButtonProps, "mode">,
+) => <DateTimePickerButton {...props} mode="date" />;
+
+export const TimePickerButton = (
+  props: Omit<DateTimePickerButtonProps, "mode">,
+) => <DateTimePickerButton {...props} mode="time" />;
+
+export default DateTimePickerButton;

apps/client/src/components/DeleteEventModal.tsx

@@ -0,0 +1,100 @@
+import { Pressable, Text, View } from "react-native";
+import { RecurringDeleteMode } from "@calchat/shared";
+import { useThemeStore } from "../stores/ThemeStore";
+import { ModalBase } from "./ModalBase";
+
+type DeleteEventModalProps = {
+  visible: boolean;
+  eventTitle: string;
+  isRecurring: boolean;
+  onConfirm: (mode: RecurringDeleteMode) => void;
+  onCancel: () => void;
+};
+
+type DeleteOption = {
+  mode: RecurringDeleteMode;
+  label: string;
+};
+
+const RECURRING_DELETE_OPTIONS: DeleteOption[] = [
+  {
+    mode: "single",
+    label: "Nur dieses Vorkommen",
+  },
+  {
+    mode: "future",
+    label: "Dieses und zukünftige",
+  },
+  {
+    mode: "all",
+    label: "Alle Vorkommen",
+  },
+];
+
+export const DeleteEventModal = ({
+  visible,
+  eventTitle,
+  isRecurring,
+  onConfirm,
+  onCancel,
+}: DeleteEventModalProps) => {
+  const { theme } = useThemeStore();
+
+  const title = isRecurring
+    ? "Wiederkehrenden Termin löschen"
+    : "Termin loeschen";
+
+  return (
+    <ModalBase
+      visible={visible}
+      onClose={onCancel}
+      title={title}
+      subtitle={eventTitle}
+      footer={{ label: "Abbrechen", onPress: onCancel }}
+    >
+      {isRecurring ? (
+        // Recurring event: show three options
+        RECURRING_DELETE_OPTIONS.map((option) => (
+          <Pressable
+            key={option.mode}
+            onPress={() => onConfirm(option.mode)}
+            className="py-3 px-4 rounded-lg mb-2"
+            style={{
+              backgroundColor: theme.secondaryBg,
+              borderWidth: 1,
+              borderColor: theme.borderPrimary,
+            }}
+          >
+            <Text
+              className="font-medium text-base"
+              style={{ color: theme.textPrimary }}
+            >
+              {option.label}
+            </Text>
+          </Pressable>
+        ))
+      ) : (
+        // Non-recurring event: simple confirmation
+        <View>
+          <Text className="text-base mb-4" style={{ color: theme.textPrimary }}>
+            Möchtest du diesen Termin wirklich löschen?
+          </Text>
+          <Pressable
+            onPress={() => onConfirm("all")}
+            className="py-3 px-4 rounded-lg"
+            style={{
+              backgroundColor: theme.rejectButton,
+            }}
+          >
+            <Text
+              className="font-medium text-base text-center"
+              style={{ color: theme.buttonText }}
+            >
+              Löschen
+            </Text>
+          </Pressable>
+        </View>
+      )}
+    </ModalBase>
+  );
+};

apps/client/src/components/EventCard.tsx

@@ -1,7 +1,7 @@
-import { View, Pressable } from "react-native";
+import { View, TouchableOpacity } from "react-native";
-import { ExpandedEvent } from "@caldav/shared";
+import { ExpandedEvent } from "@calchat/shared";
 import { Feather } from "@expo/vector-icons";
-import currentTheme from "../Themes";
+import { useThemeStore } from "../stores/ThemeStore";
 import { EventCardBase } from "./EventCardBase";
 
 type EventCardProps = {
@@ -11,6 +11,7 @@ type EventCardProps = {
 };
 
 export const EventCard = ({ event, onEdit, onDelete }: EventCardProps) => {
+  const { theme } = useThemeStore();
   return (
     <View className="mb-3">
       <EventCardBase
@@ -18,34 +19,34 @@ export const EventCard = ({ event, onEdit, onDelete }: EventCardProps) => {
         startTime={event.occurrenceStart}
         endTime={event.occurrenceEnd}
         description={event.description}
-        isRecurring={event.isRecurring}
+        recurrenceRule={event.recurrenceRule}
       >
-        {/* Action buttons */}
+        {/* Action buttons - TouchableOpacity with delayPressIn allows ScrollView to detect scroll gestures */}
         <View className="flex-row justify-end mt-3 gap-3">
-          <Pressable
+          <TouchableOpacity
             onPress={onEdit}
+            delayPressIn={100}
+            activeOpacity={0.7}
             className="w-10 h-10 rounded-full items-center justify-center"
             style={{
               borderWidth: 1,
-              borderColor: currentTheme.borderPrimary,
+              borderColor: theme.borderPrimary,
             }}
           >
-            <Feather name="edit-2" size={18} color={currentTheme.textPrimary} />
+            <Feather name="edit-2" size={18} color={theme.textPrimary} />
-          </Pressable>
+          </TouchableOpacity>
-          <Pressable
+          <TouchableOpacity
             onPress={onDelete}
+            delayPressIn={100}
+            activeOpacity={0.7}
             className="w-10 h-10 rounded-full items-center justify-center"
             style={{
               borderWidth: 1,
-              borderColor: currentTheme.borderPrimary,
+              borderColor: theme.borderPrimary,
             }}
           >
-            <Feather
+            <Feather name="trash-2" size={18} color={theme.textPrimary} />
-              name="trash-2"
+          </TouchableOpacity>
-              size={18}
-              color={currentTheme.textPrimary}
-            />
-          </Pressable>
         </View>
       </EventCardBase>
     </View>

apps/client/src/components/EventCardBase.tsx

@@ -1,7 +1,15 @@
 import { View, Text } from "react-native";
 import { Feather } from "@expo/vector-icons";
 import { ReactNode } from "react";
-import currentTheme from "../Themes";
+import { useThemeStore } from "../stores/ThemeStore";
+import { CardBase } from "./CardBase";
+import {
+  isMultiDayEvent,
+  formatDateWithWeekday,
+  formatDateWithWeekdayShort,
+  formatTime,
+  formatRecurrenceRule,
+} from "@calchat/shared";
 
 type EventCardBaseProps = {
   className?: string;
@@ -9,28 +17,10 @@ type EventCardBaseProps = {
   startTime: Date;
   endTime: Date;
   description?: string;
-  isRecurring?: boolean;
+  recurrenceRule?: string;
   children?: ReactNode;
 };
 
-function formatDate(date: Date): string {
-  const d = new Date(date);
-  return d.toLocaleDateString("de-DE", {
-    weekday: "short",
-    day: "2-digit",
-    month: "2-digit",
-    year: "numeric",
-  });
-}
-
-function formatTime(date: Date): string {
-  const d = new Date(date);
-  return d.toLocaleTimeString("de-DE", {
-    hour: "2-digit",
-    minute: "2-digit",
-  });
-}
-
 function formatDuration(start: Date, end: Date): string {
   const startDate = new Date(start);
   const endDate = new Date(end);
@@ -57,84 +47,79 @@ export const EventCardBase = ({
   startTime,
   endTime,
   description,
-  isRecurring,
+  recurrenceRule,
   children,
 }: EventCardBaseProps) => {
+  const { theme } = useThemeStore();
+  const multiDay = isMultiDayEvent(startTime, endTime);
+
   return (
-    <View
+    <CardBase title={title} className={className} borderWidth={2}>
-      className={`rounded-xl overflow-hidden ${className}`}
+      {/* Date */}
-      style={{ borderWidth: 2, borderColor: currentTheme.borderPrimary }}
+      <View className="flex-row items-center mb-1">
-    >
+        <Feather
-      {/* Header with title */}
+          name="calendar"
-      <View
+          size={16}
-        className="px-3 py-2"
+          color={theme.textPrimary}
-        style={{
+          style={{ marginRight: 8 }}
-          backgroundColor: currentTheme.chatBot,
+        />
-          borderBottomWidth: 2,
+        {multiDay ? (
-          borderBottomColor: currentTheme.borderPrimary,
+          <Text style={{ color: theme.textPrimary }}>
-        }}
+            {formatDateWithWeekdayShort(startTime)} →{" "}
-      >
+            {formatDateWithWeekday(endTime)}
-        <Text className="font-bold text-base">{title}</Text>
+          </Text>
+        ) : (
+          <Text style={{ color: theme.textPrimary }}>
+            {formatDateWithWeekday(startTime)}
+          </Text>
+        )}
       </View>
 
-      {/* Content */}
+      {/* Time with duration */}
-      <View className="px-3 py-2 bg-white">
+      <View className="flex-row items-center mb-1">
-        {/* Date */}
+        <Feather
-        <View className="flex-row items-center mb-1">
+          name="clock"
-          <Feather
+          size={16}
-            name="calendar"
+          color={theme.textPrimary}
-            size={16}
+          style={{ marginRight: 8 }}
-            color={currentTheme.textPrimary}
+        />
-            style={{ marginRight: 8 }}
+        {multiDay ? (
-          />
+          <Text style={{ color: theme.textPrimary }}>
-          <Text style={{ color: currentTheme.textPrimary }}>
+            {formatTime(startTime)} → {formatTime(endTime)}
-            {formatDate(startTime)}
           </Text>
-        </View>
+        ) : (
-
+          <Text style={{ color: theme.textPrimary }}>
-        {/* Time with duration */}
-        <View className="flex-row items-center mb-1">
-          <Feather
-            name="clock"
-            size={16}
-            color={currentTheme.textPrimary}
-            style={{ marginRight: 8 }}
-          />
-          <Text style={{ color: currentTheme.textPrimary }}>
             {formatTime(startTime)} - {formatTime(endTime)} (
             {formatDuration(startTime, endTime)})
           </Text>
-        </View>
-
-        {/* Recurring indicator */}
-        {isRecurring && (
-          <View className="flex-row items-center mb-1">
-            <Feather
-              name="repeat"
-              size={16}
-              color={currentTheme.textPrimary}
-              style={{ marginRight: 8 }}
-            />
-            <Text style={{ color: currentTheme.textPrimary }}>
-              Wiederkehrend
-            </Text>
-          </View>
         )}
-
-        {/* Description */}
-        {description && (
-          <Text
-            style={{ color: currentTheme.textPrimary }}
-            className="text-sm mt-1"
-          >
-            {description}
-          </Text>
-        )}
-
-        {/* Action buttons slot */}
-        {children}
       </View>
-    </View>
+
+      {/* Recurring indicator */}
+      {recurrenceRule && (
+        <View className="flex-row items-center mb-1">
+          <Feather
+            name="repeat"
+            size={16}
+            color={theme.textPrimary}
+            style={{ marginRight: 8 }}
+          />
+          <Text style={{ color: theme.textPrimary }}>
+            {formatRecurrenceRule(recurrenceRule)}
+          </Text>
+        </View>
+      )}
+
+      {/* Description */}
+      {description && (
+        <Text style={{ color: theme.textPrimary }} className="text-sm mt-1">
+          {description}
+        </Text>
+      )}
+
+      {/* Action buttons slot */}
+      {children}
+    </CardBase>
   );
 };
 

apps/client/src/components/EventConfirmDialog.tsx

@@ -1,5 +1,6 @@
 import { View, Text, Modal, Pressable } from "react-native";
-import { CreateEventDTO } from "@caldav/shared";
+import { CreateEventDTO } from "@calchat/shared";
+import { useThemeStore } from "../stores/ThemeStore";
 
 type EventConfirmDialogProps = {
   visible: boolean;
@@ -16,6 +17,8 @@ const EventConfirmDialog = ({
   onReject: _onReject,
   onClose: _onClose,
 }: EventConfirmDialogProps) => {
+  const { theme } = useThemeStore();
+
   // TODO: Display proposed event details (title, time, description)
   // TODO: Confirm button calls onConfirm and closes dialog
   // TODO: Reject button calls onReject and closes dialog
@@ -26,7 +29,9 @@ const EventConfirmDialog = ({
     <Modal visible={false} transparent animationType="fade">
       <View>
         <Pressable>
-          <Text>EventConfirmDialog - Not Implemented</Text>
+          <Text style={{ color: theme.textPrimary }}>
+            EventConfirmDialog - Not Implemented
+          </Text>
         </Pressable>
       </View>
     </Modal>

apps/client/src/components/Header.tsx

@@ -1,6 +1,7 @@
-import { View } from "react-native";
+import { View, Text, Pressable } from "react-native";
-import currentTheme from "../Themes";
+import { useThemeStore } from "../stores/ThemeStore";
-import { ReactNode } from "react";
+import { ComponentProps, ReactNode } from "react";
+import { Ionicons } from "@expo/vector-icons";
 
 type HeaderProps = {
   children?: ReactNode;
@@ -8,12 +9,13 @@ type HeaderProps = {
 };
 
 const Header = (props: HeaderProps) => {
+  const { theme } = useThemeStore();
   return (
     <View>
       <View
         className={`w-full h-32 pt-10 pb-4 ${props.className}`}
         style={{
-          backgroundColor: currentTheme.chatBot,
+          backgroundColor: theme.chatBot,
         }}
       >
         {props.children}
@@ -21,7 +23,7 @@ const Header = (props: HeaderProps) => {
       <View
         className="h-2 bg-black"
         style={{
-          shadowColor: "#000",
+          shadowColor: theme.shadowColor,
           shadowOffset: {
             width: 0,
             height: 5,
@@ -36,4 +38,54 @@ const Header = (props: HeaderProps) => {
   );
 };
 
+type HeaderButton = {
+  className?: string;
+  iconName: ComponentProps<typeof Ionicons>["name"];
+  iconSize: number;
+  onPress?: () => void;
+};
+
+export const HeaderButton = (props: HeaderButton) => {
+  const { theme } = useThemeStore();
+
+  return (
+    <Pressable
+      onPress={props.onPress}
+      className={
+        "w-16 h-16 flex items-center justify-center mx-2 rounded-xl border border-solid absolute left-6 " +
+        props.className
+      }
+      style={{
+        backgroundColor: theme.chatBot,
+        borderColor: theme.primeFg,
+        // iOS shadow
+        shadowColor: theme.shadowColor,
+        shadowOffset: { width: 0, height: 4 },
+        shadowOpacity: 0.3,
+        shadowRadius: 8,
+        // Android shadow
+        elevation: 6,
+      }}
+    >
+      <Ionicons
+        name={props.iconName}
+        size={props.iconSize}
+        color={theme.buttonText}
+      />
+    </Pressable>
+  );
+};
+
+type SimpleHeaderProps = {
+  text: string;
+};
+
+export const SimpleHeader = ({ text }: SimpleHeaderProps) => (
+  <Header>
+    <View className="h-full flex justify-center">
+      <Text className="text-center text-3xl font-bold">{text}</Text>
+    </View>
+  </Header>
+);
+
 export default Header;

apps/client/src/components/ModalBase.tsx

@@ -0,0 +1,79 @@
+import { Modal, Pressable, View } from "react-native";
+import { ReactNode } from "react";
+import { useThemeStore } from "../stores/ThemeStore";
+import { CardBase } from "./CardBase";
+
+type ModalBaseProps = {
+  visible: boolean;
+  onClose: () => void;
+  title: string;
+  subtitle?: string;
+  children: ReactNode;
+  attachment?: ReactNode;
+  footer?: {
+    label: string;
+    onPress: () => void;
+  };
+  scrollable?: boolean;
+  maxContentHeight?: number;
+};
+
+export const ModalBase = ({
+  visible,
+  onClose,
+  title,
+  subtitle,
+  children,
+  attachment,
+  footer,
+  scrollable,
+  maxContentHeight,
+}: ModalBaseProps) => {
+  const { theme } = useThemeStore();
+
+  return (
+    <Modal
+      visible={visible}
+      transparent={true}
+      animationType="fade"
+      onRequestClose={onClose}
+    >
+      <View className="flex-1 justify-center items-center">
+        {/* Backdrop - absolute positioned behind the card */}
+        <Pressable
+          className="absolute inset-0"
+          style={{ backgroundColor: "rgba(0,0,0,0.5)" }}
+          onPress={onClose}
+        />
+        {/* Card content - on top, naturally blocks touches to backdrop */}
+        <View
+          className="w-11/12 rounded-2xl overflow-hidden"
+          style={{
+            backgroundColor: theme.primeBg,
+            borderWidth: 4,
+            borderColor: theme.borderPrimary,
+          }}
+        >
+          <CardBase
+            title={title}
+            subtitle={subtitle}
+            attachment={attachment}
+            footer={footer}
+            scrollable={scrollable}
+            maxContentHeight={maxContentHeight}
+            borderWidth={0}
+            headerBorderWidth={3}
+            headerPadding={4}
+            contentPadding={4}
+            headerTextSize="text-lg"
+            contentBg={theme.primeBg}
+          >
+            {children}
+          </CardBase>
+        </View>
+      </View>
+    </Modal>
+  );
+};
+
+export default ModalBase;

apps/client/src/components/ProposedEventCard.tsx

@@ -1,70 +1,105 @@
 import { View, Text, Pressable } from "react-native";
-import { ProposedEventChange } from "@caldav/shared";
+import { Feather, Ionicons } from "@expo/vector-icons";
-import currentTheme from "../Themes";
+import { ProposedEventChange, formatDate, formatTime } from "@calchat/shared";
+import { rrulestr } from "rrule";
+import { useThemeStore } from "../stores/ThemeStore";
 import { EventCardBase } from "./EventCardBase";
 
 type ProposedEventCardProps = {
   proposedChange: ProposedEventChange;
-  respondedAction?: "confirm" | "reject";
+  onConfirm: (proposal: ProposedEventChange) => void;
-  onConfirm: () => void;
   onReject: () => void;
+  onEdit?: (proposal: ProposedEventChange) => void;
 };
 
-const ConfirmRejectButtons = ({
+const ActionButtons = ({
   isDisabled,
   respondedAction,
+  showEdit,
   onConfirm,
   onReject,
+  onEdit,
 }: {
   isDisabled: boolean;
   respondedAction?: "confirm" | "reject";
+  showEdit: boolean;
   onConfirm: () => void;
   onReject: () => void;
-}) => (
+  onEdit?: () => void;
-  <View className="flex-row mt-3 gap-2">
+}) => {
-    <Pressable
+  const { theme } = useThemeStore();
-      onPress={onConfirm}
+  return (
-      disabled={isDisabled}
+    <View className="flex-row mt-3 gap-2">
-      className="flex-1 py-2 rounded-lg items-center"
+      <Pressable
-      style={{
+        onPress={onConfirm}
-        backgroundColor: isDisabled
+        disabled={isDisabled}
-          ? currentTheme.disabledButton
+        className="flex-1 py-2 rounded-lg items-center"
-          : currentTheme.confirmButton,
+        style={{
-        borderWidth: respondedAction === "confirm" ? 2 : 0,
+          backgroundColor: isDisabled
-        borderColor: currentTheme.confirmButton,
+            ? theme.disabledButton
-      }}
+            : theme.confirmButton,
-    >
+          borderWidth: respondedAction === "confirm" ? 2 : 0,
-      <Text style={{ color: currentTheme.buttonText }} className="font-medium">
+          borderColor: theme.confirmButton,
-        Annehmen
+        }}
-      </Text>
+      >
-    </Pressable>
+        <Text style={{ color: theme.buttonText }} className="font-medium">
-    <Pressable
+          Annehmen
-      onPress={onReject}
+        </Text>
-      disabled={isDisabled}
+      </Pressable>
-      className="flex-1 py-2 rounded-lg items-center"
+      <Pressable
-      style={{
+        onPress={onReject}
-        backgroundColor: isDisabled
+        disabled={isDisabled}
-          ? currentTheme.disabledButton
+        className="flex-1 py-2 rounded-lg items-center"
-          : currentTheme.rejectButton,
+        style={{
-        borderWidth: respondedAction === "reject" ? 2 : 0,
+          backgroundColor: isDisabled
-        borderColor: currentTheme.rejectButton,
+            ? theme.disabledButton
-      }}
+            : theme.rejectButton,
-    >
+          borderWidth: respondedAction === "reject" ? 2 : 0,
-      <Text style={{ color: currentTheme.buttonText }} className="font-medium">
+          borderColor: theme.rejectButton,
-        Ablehnen
+        }}
-      </Text>
+      >
-    </Pressable>
+        <Text style={{ color: theme.buttonText }} className="font-medium">
-  </View>
+          Ablehnen
-);
+        </Text>
+      </Pressable>
+      {showEdit && onEdit && (
+        <Pressable
+          onPress={onEdit}
+          className="py-2 px-3 rounded-lg items-center"
+          style={{
+            backgroundColor: theme.secondaryBg,
+            borderWidth: 1,
+            borderColor: theme.borderPrimary,
+          }}
+        >
+          <Feather name="edit-2" size={18} color={theme.textPrimary} />
+        </Pressable>
+      )}
+    </View>
+  );
+};
 
 export const ProposedEventCard = ({
   proposedChange,
-  respondedAction,
   onConfirm,
   onReject,
+  onEdit,
 }: ProposedEventCardProps) => {
+  const { theme } = useThemeStore();
   const event = proposedChange.event;
-  const isDisabled = !!respondedAction;
+  const isDisabled = !!proposedChange.respondedAction;
+
+  // For delete/single action, the occurrenceDate becomes a new exception
+  const newExceptionDate =
+    proposedChange.action === "delete" &&
+    proposedChange.deleteMode === "single" &&
+    proposedChange.occurrenceDate;
+
+  // For update actions, check if a new UNTIL date is being set
+  const newUntilDate =
+    proposedChange.action === "update" &&
+    event?.recurrenceRule &&
+    rrulestr(event.recurrenceRule).options.until;
 
   if (!event) {
     return null;
@@ -78,13 +113,73 @@ export const ProposedEventCard = ({
         startTime={event.startTime}
         endTime={event.endTime}
         description={event.description}
-        isRecurring={event.isRecurring}
+        recurrenceRule={event.recurrenceRule}
       >
-        <ConfirmRejectButtons
+        {/* Show new exception date for delete/single actions */}
+        {newExceptionDate && (
+          <View className="flex-row items-center mb-2">
+            <Feather
+              name="plus-circle"
+              size={16}
+              color={theme.confirmButton}
+              style={{ marginRight: 8 }}
+            />
+            <Text
+              style={{ color: theme.confirmButton }}
+              className="font-medium"
+            >
+              Neue Ausnahme:{" "}
+              {formatDate(new Date(proposedChange.occurrenceDate!))}
+            </Text>
+          </View>
+        )}
+        {/* Show new UNTIL date for update actions */}
+        {newUntilDate && (
+          <View className="flex-row items-center mb-2">
+            <Feather
+              name="plus-circle"
+              size={16}
+              color={theme.confirmButton}
+              style={{ marginRight: 8 }}
+            />
+            <Text
+              style={{ color: theme.confirmButton }}
+              className="font-medium"
+            >
+              Neues Ende: {formatDate(newUntilDate)}
+            </Text>
+          </View>
+        )}
+        {/* Show conflicting events warning */}
+        {proposedChange.conflictingEvents &&
+          proposedChange.conflictingEvents.length > 0 && (
+            <View className="mb-2">
+              {proposedChange.conflictingEvents.map((conflict, index) => (
+                <View key={index} className="flex-row items-center mt-1">
+                  <Ionicons
+                    name="alert-circle"
+                    size={16}
+                    color={theme.rejectButton}
+                    style={{ marginRight: 8 }}
+                  />
+                  <Text
+                    style={{ color: theme.rejectButton }}
+                    className="text-sm flex-1"
+                  >
+                    Konflikt: {conflict.title} ({formatTime(conflict.startTime)}{" "}
+                    - {formatTime(conflict.endTime)})
+                  </Text>
+                </View>
+              ))}
+            </View>
+          )}
+        <ActionButtons
           isDisabled={isDisabled}
-          respondedAction={respondedAction}
+          respondedAction={proposedChange.respondedAction}
-          onConfirm={onConfirm}
+          showEdit={proposedChange.action !== "delete" && !isDisabled}
+          onConfirm={() => onConfirm(proposedChange)}
           onReject={onReject}
+          onEdit={onEdit ? () => onEdit(proposedChange) : undefined}
         />
       </EventCardBase>
     </View>

apps/client/src/components/ScrollableDropdown.tsx

@@ -0,0 +1,107 @@
+import { useRef, useEffect } from "react";
+import { Modal, Pressable, Animated, useWindowDimensions } from "react-native";
+import { FlashList } from "@shopify/flash-list";
+import { useThemeStore } from "../stores/ThemeStore";
+import { Theme } from "../Themes";
+
+export type ScrollableDropdownProps<T> = {
+  visible: boolean;
+  onClose: () => void;
+  position: {
+    top?: number;
+    bottom?: number;
+    left: number;
+    width: number;
+  };
+  data: T[];
+  keyExtractor: (item: T) => string;
+  renderItem: (item: T, theme: Theme) => React.ReactNode;
+  onSelect: (item: T) => void;
+  height?: number;
+  heightRatio?: number; // Alternative: fraction of screen height (0-1)
+  initialScrollIndex?: number;
+  // Infinite scroll (optional)
+  onEndReached?: () => void;
+  onStartReached?: () => void;
+};
+
+export const ScrollableDropdown = <T,>({
+  visible,
+  onClose,
+  position,
+  data,
+  keyExtractor,
+  renderItem,
+  onSelect,
+  height = 200,
+  heightRatio,
+  initialScrollIndex = 0,
+  onEndReached,
+  onStartReached,
+}: ScrollableDropdownProps<T>) => {
+  const { theme } = useThemeStore();
+  const { height: screenHeight } = useWindowDimensions();
+  const heightAnim = useRef(new Animated.Value(0)).current;
+  const listRef = useRef<React.ComponentRef<typeof FlashList<T>>>(null);
+
+  // Calculate actual height: use heightRatio if provided, otherwise fall back to height
+  const actualHeight = heightRatio ? screenHeight * heightRatio : height;
+  // Calculate top position: use top if provided, otherwise calculate from bottom
+  const topValue =
+    position.top ?? screenHeight - actualHeight - (position.bottom ?? 0);
+
+  useEffect(() => {
+    if (visible) {
+      Animated.timing(heightAnim, {
+        toValue: actualHeight,
+        duration: 200,
+        useNativeDriver: false,
+      }).start();
+    } else {
+      heightAnim.setValue(0);
+    }
+  }, [visible, heightAnim, actualHeight]);
+
+  return (
+    <Modal
+      visible={visible}
+      transparent={true}
+      animationType="none"
+      onRequestClose={onClose}
+    >
+      <Pressable className="flex-1 rounded-lg" onPress={onClose}>
+        <Animated.View
+          className="absolute overflow-hidden"
+          style={{
+            top: topValue,
+            left: position.left,
+            width: position.width,
+            height: heightAnim,
+            backgroundColor: theme.primeBg,
+            borderWidth: 2,
+            borderColor: theme.borderPrimary,
+            borderRadius: 8,
+          }}
+        >
+          <FlashList
+            className="w-full"
+            style={{ borderRadius: 8 }}
+            ref={listRef}
+            keyExtractor={keyExtractor}
+            data={data}
+            initialScrollIndex={initialScrollIndex}
+            onEndReachedThreshold={0.5}
+            onEndReached={onEndReached}
+            onStartReachedThreshold={0.5}
+            onStartReached={onStartReached}
+            renderItem={({ item }) => (
+              <Pressable onPress={() => onSelect(item)}>
+                {renderItem(item, theme)}
+              </Pressable>
+            )}
+          />
+        </Animated.View>
+      </Pressable>
+    </Modal>
+  );
+};

apps/client/src/components/TypingIndicator.tsx

@@ -0,0 +1,31 @@
+import { useEffect, useState } from "react";
+import { Text } from "react-native";
+import { useThemeStore } from "../stores/ThemeStore";
+import { ChatBubble } from "./ChatBubble";
+
+const DOTS = [".", "..", "..."];
+const INTERVAL_MS = 400;
+
+export default function TypingIndicator() {
+  const { theme } = useThemeStore();
+  const [dotIndex, setDotIndex] = useState(0);
+
+  useEffect(() => {
+    const interval = setInterval(() => {
+      setDotIndex((prev) => (prev + 1) % DOTS.length);
+    }, INTERVAL_MS);
+
+    return () => clearInterval(interval);
+  }, []);
+
+  return (
+    <ChatBubble side="left" className="px-4 py-2">
+      <Text
+        className="text-lg font-bold tracking-widest"
+        style={{ color: theme.textMuted }}
+      >
+        {DOTS[dotIndex]}
+      </Text>
+    </ChatBubble>
+  );
+}

apps/client/src/hooks/useDropdownPosition.ts

@@ -0,0 +1,37 @@
+import { useCallback, useRef, useState } from "react";
+import { View } from "react-native";
+
+type DropdownPosition = {
+  top: number;
+  left: number;
+  width: number;
+};
+
+/**
+ * Hook for managing dropdown position measurement and visibility.
+ * @param widthMultiplier - Multiply the measured width (default: 1)
+ */
+export const useDropdownPosition = (widthMultiplier = 1) => {
+  const [visible, setVisible] = useState(false);
+  const [position, setPosition] = useState<DropdownPosition>({
+    top: 0,
+    left: 0,
+    width: 0,
+  });
+  const ref = useRef<View>(null);
+
+  const open = useCallback(() => {
+    ref.current?.measureInWindow((x, y, width, height) => {
+      setPosition({
+        top: y + height,
+        left: x,
+        width: width * widthMultiplier,
+      });
+      setVisible(true);
+    });
+  }, [widthMultiplier]);
+
+  const close = useCallback(() => setVisible(false), []);
+
+  return { ref, visible, position, open, close };
+};

apps/client/src/logging/index.ts

@@ -0,0 +1 @@
+export { log, apiLogger, storeLogger } from "./logger";

apps/client/src/logging/logger.ts

@@ -0,0 +1,30 @@
+import { logger, consoleTransport } from "react-native-logs";
+
+const log = logger.createLogger({
+  levels: {
+    debug: 0,
+    info: 1,
+    warn: 2,
+    error: 3,
+  },
+  severity: __DEV__ ? "debug" : "warn",
+  transport: consoleTransport,
+  transportOptions: {
+    colors: {
+      debug: "white",
+      info: "blueBright",
+      warn: "yellowBright",
+      error: "redBright",
+    },
+  },
+  async: true,
+  dateFormat: "time",
+  printLevel: true,
+  printDate: true,
+  enabled: true,
+});
+
+export const apiLogger = log.extend("API");
+export const storeLogger = log.extend("Store");
+
+export { log };

apps/client/src/services/ApiClient.ts

@@ -1,4 +1,6 @@
 import { Platform } from "react-native";
+import { apiLogger } from "../logging";
+import { useAuthStore } from "../stores";
 
 const API_BASE_URL =
   process.env.EXPO_PUBLIC_API_URL ||
@@ -12,6 +14,16 @@ type HttpMethod = "GET" | "POST" | "PUT" | "DELETE";
 interface RequestOptions {
   headers?: Record<string, string>;
   body?: unknown;
+  skipAuth?: boolean;
+}
+
+function getAuthHeaders(): Record<string, string> {
+  const user = useAuthStore.getState().user;
+  apiLogger.debug(`getAuthHeaders - user: ${JSON.stringify(user)}`);
+  if (user?.id) {
+    return { "X-User-Id": user.id };
+  }
+  return {};
 }
 
 async function request<T>(
@@ -19,20 +31,45 @@ async function request<T>(
   endpoint: string,
   options?: RequestOptions,
 ): Promise<T> {
-  const response = await fetch(`${API_BASE_URL}${endpoint}`, {
+  const start = performance.now();
-    method,
+  apiLogger.debug(`${method} ${endpoint}`);
-    headers: {
-      "Content-Type": "application/json",
-      ...options?.headers,
-    },
-    body: options?.body ? JSON.stringify(options.body) : undefined,
-  });
 
-  if (!response.ok) {
+  try {
-    throw new Error(`HTTP ${response.status}`);
+    const authHeaders = options?.skipAuth ? {} : getAuthHeaders();
+
+    const response = await fetch(`${API_BASE_URL}${endpoint}`, {
+      method,
+      headers: {
+        "Content-Type": "application/json",
+        ...authHeaders,
+        ...options?.headers,
+      },
+      body: options?.body ? JSON.stringify(options.body) : undefined,
+    });
+
+    const duration = Math.round(performance.now() - start);
+
+    if (!response.ok) {
+      apiLogger.error(
+        `${method} ${endpoint} - ${response.status} (${duration}ms)`,
+      );
+      throw new Error(`HTTP ${response.status}`);
+    }
+
+    apiLogger.debug(
+      `${method} ${endpoint} - ${response.status} (${duration}ms)`,
+    );
+
+    const text = await response.text();
+    if (!text) {
+      return undefined as T;
+    }
+    return JSON.parse(text);
+  } catch (error) {
+    const duration = Math.round(performance.now() - start);
+    apiLogger.error(`${method} ${endpoint} failed (${duration}ms): ${error}`);
+    throw error;
   }
-
-  return response.json();
 }
 
 export const ApiClient = {

apps/client/src/services/AuthService.ts

@@ -1,19 +1,29 @@
-import { LoginDTO, CreateUserDTO, AuthResponse } from "@caldav/shared";
+import { LoginDTO, CreateUserDTO, AuthResponse } from "@calchat/shared";
+import { ApiClient } from "./ApiClient";
+import { useAuthStore } from "../stores";
 
 export const AuthService = {
-  login: async (_credentials: LoginDTO): Promise<AuthResponse> => {
+  login: async (credentials: LoginDTO): Promise<AuthResponse> => {
-    throw new Error("Not implemented");
+    const response = await ApiClient.post<AuthResponse>(
+      "/auth/login",
+      credentials,
+      { skipAuth: true },
+    );
+    await useAuthStore.getState().login(response.user);
+    return response;
   },
 
-  register: async (_data: CreateUserDTO): Promise<AuthResponse> => {
+  register: async (data: CreateUserDTO): Promise<AuthResponse> => {
-    throw new Error("Not implemented");
+    const response = await ApiClient.post<AuthResponse>(
+      "/auth/register",
+      data,
+      { skipAuth: true },
+    );
+    await useAuthStore.getState().login(response.user);
+    return response;
   },
 
   logout: async (): Promise<void> => {
-    throw new Error("Not implemented");
+    await useAuthStore.getState().logout();
-  },
-
-  refresh: async (): Promise<AuthResponse> => {
-    throw new Error("Not implemented");
   },
 };

apps/client/src/services/CaldavConfigService.ts

@@ -0,0 +1,32 @@
+import { CalendarEvent, CaldavConfig } from "@calchat/shared";
+import { ApiClient } from "./ApiClient";
+
+export const CaldavConfigService = {
+  saveConfig: async (
+    serverUrl: string,
+    username: string,
+    password: string,
+  ): Promise<CaldavConfig> => {
+    return ApiClient.put<CaldavConfig>("/caldav/config", {
+      serverUrl,
+      username,
+      password,
+    });
+  },
+  getConfig: async (): Promise<CaldavConfig> => {
+    return ApiClient.get<CaldavConfig>("/caldav/config");
+  },
+  deleteConfig: async (): Promise<void> => {
+    return ApiClient.delete<void>("/caldav/config");
+  },
+  pull: async (): Promise<CalendarEvent[]> => {
+    return ApiClient.post<CalendarEvent[]>("/caldav/pull");
+  },
+  pushAll: async (): Promise<void> => {
+    return ApiClient.post<void>("/caldav/pushAll");
+  },
+  sync: async (): Promise<void> => {
+    await ApiClient.post<void>("/caldav/pushAll");
+    await ApiClient.post<CalendarEvent[]>("/caldav/pull");
+  },
+};

apps/client/src/services/ChatService.ts

@@ -7,14 +7,22 @@ import {
   CreateEventDTO,
   UpdateEventDTO,
   EventAction,
-} from "@caldav/shared";
+  RecurringDeleteMode,
+} from "@calchat/shared";
 import { ApiClient } from "./ApiClient";
 
 interface ConfirmEventRequest {
+  proposalId: string;
   action: EventAction;
   event?: CreateEventDTO;
   eventId?: string;
   updates?: UpdateEventDTO;
+  deleteMode?: RecurringDeleteMode;
+  occurrenceDate?: string;
+}
+
+interface RejectEventRequest {
+  proposalId: string;
 }
 
 export const ChatService = {
@@ -25,12 +33,23 @@ export const ChatService = {
   confirmEvent: async (
     conversationId: string,
     messageId: string,
+    proposalId: string,
     action: EventAction,
     event?: CreateEventDTO,
     eventId?: string,
     updates?: UpdateEventDTO,
+    deleteMode?: RecurringDeleteMode,
+    occurrenceDate?: string,
   ): Promise<ChatResponse> => {
-    const body: ConfirmEventRequest = { action, event, eventId, updates };
+    const body: ConfirmEventRequest = {
+      proposalId,
+      action,
+      event,
+      eventId,
+      updates,
+      deleteMode,
+      occurrenceDate,
+    };
     return ApiClient.post<ChatResponse>(
       `/chat/confirm/${conversationId}/${messageId}`,
       body,
@@ -40,9 +59,12 @@ export const ChatService = {
   rejectEvent: async (
     conversationId: string,
     messageId: string,
+    proposalId: string,
   ): Promise<ChatResponse> => {
+    const body: RejectEventRequest = { proposalId };
     return ApiClient.post<ChatResponse>(
       `/chat/reject/${conversationId}/${messageId}`,
+      body,
     );
   },
 
@@ -63,4 +85,15 @@ export const ChatService = {
 
     return ApiClient.get<ChatMessage[]>(url);
   },
+
+  updateProposalEvent: async (
+    messageId: string,
+    proposalId: string,
+    event: CreateEventDTO,
+  ): Promise<ChatMessage> => {
+    return ApiClient.put<ChatMessage>(`/chat/messages/${messageId}/proposal`, {
+      proposalId,
+      event,
+    });
+  },
 };

apps/client/src/services/EventService.ts

@@ -3,7 +3,8 @@ import {
   CreateEventDTO,
   UpdateEventDTO,
   ExpandedEvent,
-} from "@caldav/shared";
+  RecurringDeleteMode,
+} from "@calchat/shared";
 import { ApiClient } from "./ApiClient";
 
 export const EventService = {
@@ -29,7 +30,18 @@ export const EventService = {
     return ApiClient.put<CalendarEvent>(`/events/${id}`, data);
   },
 
-  delete: async (id: string): Promise<void> => {
+  delete: async (
-    return ApiClient.delete(`/events/${id}`);
+    id: string,
+    mode?: RecurringDeleteMode,
+    occurrenceDate?: string,
+  ): Promise<CalendarEvent | void> => {
+    const params = new URLSearchParams();
+    if (mode) params.append("mode", mode);
+    if (occurrenceDate) params.append("occurrenceDate", occurrenceDate);
+
+    const queryString = params.toString();
+    const url = `/events/${id}${queryString ? `?${queryString}` : ""}`;
+
+    return ApiClient.delete(url);
   },
 };

apps/client/src/stores/AuthStore.ts

@@ -1,26 +1,69 @@
 import { create } from "zustand";
-import { User } from "@caldav/shared";
+import { Platform } from "react-native";
+import { User } from "@calchat/shared";
+import * as SecureStore from "expo-secure-store";
+
+const USER_STORAGE_KEY = "auth_user";
+
+// SecureStore doesn't work on web, use localStorage as fallback
+const storage = {
+  async setItem(key: string, value: string): Promise<void> {
+    if (Platform.OS === "web") {
+      localStorage.setItem(key, value);
+    } else {
+      await SecureStore.setItemAsync(key, value);
+    }
+  },
+  async getItem(key: string): Promise<string | null> {
+    if (Platform.OS === "web") {
+      return localStorage.getItem(key);
+    }
+    return SecureStore.getItemAsync(key);
+  },
+  async deleteItem(key: string): Promise<void> {
+    if (Platform.OS === "web") {
+      localStorage.removeItem(key);
+    } else {
+      await SecureStore.deleteItemAsync(key);
+    }
+  },
+};
 
 interface AuthState {
   user: User | null;
-  token: string | null;
   isAuthenticated: boolean;
-  login: (user: User, token: string) => void;
+  isLoading: boolean;
-  logout: () => void;
+  login: (user: User) => Promise<void>;
-  setToken: (token: string) => void;
+  logout: () => Promise<void>;
+  loadStoredUser: () => Promise<void>;
 }
 
 export const useAuthStore = create<AuthState>((set) => ({
   user: null,
-  token: null,
   isAuthenticated: false,
-  login: (_user: User, _token: string) => {
+  isLoading: true,
-    throw new Error("Not implemented");
+
+  login: async (user: User) => {
+    await storage.setItem(USER_STORAGE_KEY, JSON.stringify(user));
+    set({ user, isAuthenticated: true });
   },
-  logout: () => {
+
-    throw new Error("Not implemented");
+  logout: async () => {
+    await storage.deleteItem(USER_STORAGE_KEY);
+    set({ user: null, isAuthenticated: false });
   },
-  setToken: (_token: string) => {
+
-    throw new Error("Not implemented");
+  loadStoredUser: async () => {
+    try {
+      const stored = await storage.getItem(USER_STORAGE_KEY);
+      if (stored) {
+        const user = JSON.parse(stored) as User;
+        set({ user, isAuthenticated: true, isLoading: false });
+      } else {
+        set({ isLoading: false });
+      }
+    } catch {
+      set({ isLoading: false });
+    }
   },
 }));

apps/client/src/stores/CaldavConfigStore.ts

@@ -0,0 +1,14 @@
+import { create } from "zustand";
+import { CaldavConfig } from "@calchat/shared";
+
+interface CaldavConfigState {
+  config: CaldavConfig | null;
+  setConfig: (config: CaldavConfig | null) => void;
+}
+
+export const useCaldavConfigStore = create<CaldavConfigState>((set) => ({
+  config: null,
+  setConfig: (config: CaldavConfig | null) => {
+    set({ config });
+  },
+}));

apps/client/src/stores/ChatStore.ts

@@ -1,5 +1,5 @@
 import { create } from "zustand";
-import { ChatMessage, ProposedEventChange } from "@caldav/shared";
+import { ChatMessage, ProposedEventChange } from "@calchat/shared";
 
 type BubbleSide = "left" | "right";
 
@@ -7,21 +7,23 @@ export type MessageData = {
   id: string;
   side: BubbleSide;
   content: string;
-  proposedChange?: ProposedEventChange;
+  proposedChanges?: ProposedEventChange[];
-  respondedAction?: "confirm" | "reject";
   conversationId?: string;
 };
 
 interface ChatState {
   messages: MessageData[];
+  isWaitingForResponse: boolean;
   addMessages: (messages: MessageData[]) => void;
   addMessage: (message: MessageData) => void;
   updateMessage: (id: string, updates: Partial<MessageData>) => void;
   clearMessages: () => void;
+  setWaitingForResponse: (waiting: boolean) => void;
 }
 
 export const useChatStore = create<ChatState>((set) => ({
   messages: [],
+  isWaitingForResponse: false,
   addMessages(messages) {
     set((state) => ({ messages: [...state.messages, ...messages] }));
   },
@@ -38,6 +40,9 @@ export const useChatStore = create<ChatState>((set) => ({
   clearMessages: () => {
     set({ messages: [] });
   },
+  setWaitingForResponse: (waiting: boolean) => {
+    set({ isWaitingForResponse: waiting });
+  },
 }));
 
 // Helper to convert server ChatMessage to client MessageData
@@ -46,8 +51,7 @@ export function chatMessageToMessageData(msg: ChatMessage): MessageData {
     id: msg.id,
     side: msg.sender === "assistant" ? "left" : "right",
     content: msg.content,
-    proposedChange: msg.proposedChange,
+    proposedChanges: msg.proposedChanges,
-    respondedAction: msg.respondedAction,
     conversationId: msg.conversationId,
   };
 }

apps/client/src/stores/EventsStore.ts

@@ -1,5 +1,5 @@
 import { create } from "zustand";
-import { ExpandedEvent } from "@caldav/shared";
+import { ExpandedEvent } from "@calchat/shared";
 
 interface EventsState {
   events: ExpandedEvent[];

apps/client/src/stores/ThemeStore.ts

@@ -0,0 +1,12 @@
+import { create } from "zustand";
+import { Theme, THEMES } from "../Themes";
+
+interface ThemeState {
+  theme: Theme;
+  setTheme: (themeName: keyof typeof THEMES) => void;
+}
+
+export const useThemeStore = create<ThemeState>((set) => ({
+  theme: THEMES.defaultLight,
+  setTheme: (themeName) => set({ theme: THEMES[themeName] }),
+}));

apps/client/src/stores/index.ts

@@ -5,3 +5,4 @@ export {
   type MessageData,
 } from "./ChatStore";
 export { useEventsStore } from "./EventsStore";
+export { useCaldavConfigStore } from "./CaldavConfigStore";

apps/server/.env.example

@@ -0,0 +1,28 @@
+# OpenAI API key for GPT-based chat assistant
+# Required for AI chat functionality
+OPENAI_API_KEY=sk-proj-your-key-here
+
+# Port the server listens on
+# Default: 3000
+PORT=3000
+
+# MongoDB connection URI
+# Default: mongodb://localhost:27017/calchat
+# The Docker Compose setup uses root:mongoose credentials with authSource=admin
+MONGODB_URI=mongodb://root:mongoose@localhost:27017/calchat?authSource=admin
+
+# Use static test responses instead of real GPT calls
+# Values: true | false
+# Default: false
+USE_TEST_RESPONSES=false
+
+# Log level for pino logger
+# Values: debug | info | warn | error | fatal
+# Default: debug (development), info (production)
+LOG_LEVEL=debug
+
+# Node environment
+# Values: development | production
+# development = pretty-printed logs, production = JSON logs
+# Default: development
+NODE_ENV=development

apps/server/docker/Dockerfile

@@ -0,0 +1,31 @@
+FROM node:alpine AS build
+
+WORKDIR /app
+
+COPY package.json package-lock.json tsconfig.json ./
+COPY packages/shared/package.json ./packages/shared/
+COPY apps/server/package.json ./apps/server/
+
+RUN npm ci -w @calchat/server -w @calchat/shared --include-workspace-root
+
+COPY packages/shared/ packages/shared/
+COPY apps/server/ apps/server/
+
+RUN npm run build -w @calchat/shared && npm run build -w @calchat/server
+
+FROM node:alpine
+
+WORKDIR /app
+
+COPY --from=build /app/package.json /app/package-lock.json ./
+COPY --from=build /app/packages/shared/package.json packages/shared/
+COPY --from=build /app/apps/server/package.json apps/server/
+
+RUN npm ci --omit=dev -w @calchat/server -w @calchat/shared
+
+COPY --from=build /app/packages/shared/dist/ packages/shared/dist/
+COPY --from=build /app/apps/server/dist/ apps/server/dist/
+
+EXPOSE 3001
+
+CMD ["node", "apps/server/dist/app.js"]

apps/server/docker/radicale/docker-compose.yml

@@ -0,0 +1,25 @@
+name: Radicale
+services:
+    radicale:
+        image: ghcr.io/kozea/radicale:stable
+        ports:
+        - 5232:5232
+        volumes:
+          - config:/etc/radicale
+          - data:/var/lib/radicale
+
+volumes:
+  config:
+    name: radicale-config
+    driver: local
+    driver_opts:
+      type: none
+      o: bind
+      device: ./config
+  data:
+    name: radicale-data
+    driver: local
+    driver_opts:
+      type: none
+      o: bind
+      device: ./data

apps/server/jest.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+  preset: "ts-jest",
+  testEnvironment: "node",
+  testPathIgnorePatterns: ["/node_modules/", "/dist/"],
+};

apps/server/package.json

@@ -1,27 +1,35 @@
 {
-  "name": "@caldav/server",
+  "name": "@calchat/server",
   "version": "1.0.0",
   "private": true,
   "scripts": {
-    "dev": "tsx watch src/app.ts",
+    "dev": "npm run build --workspace=@calchat/shared && tsx watch src/app.ts",
-    "build": "tsc",
+    "build": "npm run build --workspace=@calchat/shared && tsc",
-    "start": "node dist/app.js"
+    "start": "node dist/app.js",
+    "test": "jest"
   },
   "dependencies": {
-    "@caldav/shared": "*",
+    "@calchat/shared": "*",
     "bcrypt": "^6.0.0",
     "dotenv": "^16.4.7",
     "express": "^5.2.1",
-    "jsonwebtoken": "^9.0.3",
+    "ical.js": "^2.2.1",
     "mongoose": "^9.1.1",
     "openai": "^6.15.0",
-    "rrule": "^2.8.1"
+    "pino": "^10.1.1",
+    "pino-http": "^11.0.0",
+    "pino-pretty": "^13.1.3",
+    "rrule": "^2.8.1",
+    "tsdav": "^2.1.6"
   },
   "devDependencies": {
     "@types/bcrypt": "^6.0.0",
     "@types/express": "^5.0.6",
-    "@types/jsonwebtoken": "^9.0.10",
+    "@types/ical": "^0.8.3",
+    "@types/jest": "^30.0.0",
     "@types/node": "^24.10.1",
+    "jest": "^30.2.0",
+    "ts-jest": "^29.4.6",
     "tsx": "^4.21.0",
     "typescript": "^5.9.3"
   }

apps/server/scripts/hash-password.js

@@ -0,0 +1,10 @@
+const bcrypt = require("bcrypt");
+
+const password = process.argv[2];
+
+if (!password) {
+  console.error("Usage: node scripts/hash-password.js <password>");
+  process.exit(1);
+}
+
+bcrypt.hash(password, 10).then((hash) => console.log(hash));

apps/server/src/ai/GPTAdapter.ts

@@ -1,5 +1,5 @@
 import OpenAI from "openai";
-import { ProposedEventChange } from "@caldav/shared";
+import { ProposedEventChange } from "@calchat/shared";
 import { AIProvider, AIContext, AIResponse } from "../services/interfaces";
 import {
   buildSystemPrompt,
@@ -7,6 +7,12 @@ import {
   executeToolCall,
   ToolDefinition,
 } from "./utils";
+import { Logged } from "../logging";
+import {
+  ChatCompletionMessageParam,
+  ChatCompletionMessageToolCall,
+  ChatCompletionTool,
+} from "openai/resources/chat/completions/completions";
 
 /**
  * Convert tool definitions to OpenAI format.
@@ -24,10 +30,11 @@ function toOpenAITools(
   }));
 }
 
+@Logged("GPTAdapter")
 export class GPTAdapter implements AIProvider {
   private client: OpenAI;
   private model: string;
-  private tools: OpenAI.Chat.Completions.ChatCompletionTool[];
+  private tools: ChatCompletionTool[];
 
   constructor(apiKey?: string, model: string = "gpt-5-mini") {
     this.client = new OpenAI({
@@ -44,7 +51,7 @@ export class GPTAdapter implements AIProvider {
     const systemPrompt = buildSystemPrompt(context);
 
     // Build messages array with conversation history
-    const messages: OpenAI.Chat.Completions.ChatCompletionMessageParam[] = [
+    const messages: ChatCompletionMessageParam[] = [
       { role: "developer", content: systemPrompt },
     ];
 
@@ -59,7 +66,8 @@ export class GPTAdapter implements AIProvider {
     // Add current user message
     messages.push({ role: "user", content: message });
 
-    let proposedChange: ProposedEventChange | undefined;
+    const proposedChanges: ProposedEventChange[] = [];
+    let proposalIndex = 0;
 
     // Tool calling loop
     while (true) {
@@ -79,36 +87,49 @@ export class GPTAdapter implements AIProvider {
         return {
           content:
             assistantMessage.content || "Ich konnte keine Antwort generieren.",
-          proposedChange,
+          proposedChanges:
+            proposedChanges.length > 0 ? proposedChanges : undefined,
         };
       }
 
-      // Process tool calls
+      // Process all tool calls and collect results
+      const toolResults: Array<{
+        toolCall: ChatCompletionMessageToolCall;
+        content: string;
+      }> = [];
+
       for (const toolCall of assistantMessage.tool_calls) {
-        // Skip non-function tool calls
         if (toolCall.type !== "function") continue;
 
         const { name, arguments: argsRaw } = toolCall.function;
         const args = JSON.parse(argsRaw);
 
-        const result = executeToolCall(name, args, context);
+        const result = await executeToolCall(name, args, context);
 
-        // If the tool returned a proposedChange, capture it
+        // Collect proposed changes
         if (result.proposedChange) {
-          proposedChange = result.proposedChange;
+          proposedChanges.push({
+            id: `proposal-${proposalIndex++}`,
+            ...result.proposedChange,
+          });
         }
 
-        // Add assistant message with tool call
+        toolResults.push({ toolCall, content: result.content });
-        messages.push({
+      }
-          role: "assistant",
-          tool_calls: [toolCall],
-        });
 
-        // Add tool result
+      // Add assistant message with ALL tool calls at once
+      messages.push({
+        role: "assistant",
+        tool_calls: assistantMessage.tool_calls,
+        content: assistantMessage.content,
+      });
+
+      // Add all tool results
+      for (const { toolCall, content } of toolResults) {
         messages.push({
           role: "tool",
           tool_call_id: toolCall.id,
-          content: result.content,
+          content,
         });
       }
     }

apps/server/src/ai/utils/eventFormatter.ts

@@ -1,29 +0,0 @@
-import { CalendarEvent } from "@caldav/shared";
-
-// German date/time formatting helpers
-export const formatDate = (d: Date) => d.toLocaleDateString("de-DE");
-export const formatTime = (d: Date) =>
-  d.toLocaleTimeString("de-DE", { hour: "2-digit", minute: "2-digit" });
-export const formatDateTime = (d: Date) =>
-  `${formatDate(d)} ${d.toLocaleTimeString("de-DE")}`;
-
-/**
- * Format a list of events for display in the system prompt.
- * Output is in German with date/time formatting.
- */
-export function formatExistingEvents(events: CalendarEvent[]): string {
-  if (events.length === 0) {
-    return "Keine Termine vorhanden.";
-  }
-
-  return events
-    .map((e) => {
-      const start = new Date(e.startTime);
-      const end = new Date(e.endTime);
-      const timeStr = `${formatTime(start)} - ${formatTime(end)}`;
-      const recurring = e.isRecurring ? " (wiederkehrend)" : "";
-      const desc = e.description ? ` | ${e.description}` : "";
-      return `- ${e.title} (ID: ${e.id}) | ${formatDate(start)} ${timeStr}${recurring}${desc}`;
-    })
-    .join("\n");
-}

apps/server/src/ai/utils/index.ts

@@ -1,9 +1,3 @@
-export {
-  formatExistingEvents,
-  formatDate,
-  formatTime,
-  formatDateTime,
-} from "./eventFormatter";
 export { buildSystemPrompt } from "./systemPrompt";
 export {
   TOOL_DEFINITIONS,

apps/server/src/ai/utils/systemPrompt.ts

@@ -1,5 +1,4 @@
 import { AIContext } from "../../services/interfaces";
-import { formatExistingEvents } from "./eventFormatter";
 
 /**
  * Build the system prompt for the AI assistant.
@@ -15,8 +14,6 @@ export function buildSystemPrompt(context: AIContext): string {
     minute: "2-digit",
   });
 
-  const eventsText = formatExistingEvents(context.existingEvents);
-
   return `Du bist ein hilfreicher Kalender-Assistent für die App "CalChat".
 Du hilfst Benutzern beim Erstellen, Ändern und Löschen von Terminen.
 Antworte immer auf Deutsch.
@@ -28,10 +25,51 @@ Wichtige Regeln:
 - Wenn der Benutzer einen Termin erstellen will, nutze proposeCreateEvent
 - Wenn der Benutzer einen Termin ändern will, nutze proposeUpdateEvent mit der Event-ID
 - Wenn der Benutzer einen Termin löschen will, nutze proposeDeleteEvent mit der Event-ID
-- Du kannst NUR EINEN Event-Vorschlag pro Antwort machen
+- Du kannst mehrere Event-Vorschläge in einer Antwort machen (z.B. für mehrere Termine auf einmal)
-- Wenn der Benutzer nach seinen Terminen fragt, nutze die unten stehende Liste
+- WICHTIG: Bei Terminen in der VERGANGENHEIT: Weise den Benutzer darauf hin und erstelle KEIN Event. Beispiel: "Das Datum liegt in der Vergangenheit. Meintest du vielleicht [nächstes Jahr]?"
-- Nutze searchEvents um nach Terminen zu suchen, wenn du die genaue ID brauchst
+- KRITISCH: Wenn ein Tool-Result eine ⚠️-Warnung enthält (z.B. "Zeitkonflikt mit..."), MUSST du diese dem Benutzer mitteilen! Ignoriere NIEMALS solche Warnungen! Beispiel: "An diesem Tag hast du bereits 'Jannes Geburtstag'. Soll ich den Termin trotzdem erstellen?"
 
-Existierende Termine des Benutzers:
+WICHTIG - Event-Abfragen:
-${eventsText}`;
+- Du hast KEINEN vorgeladenen Kalender-Kontext!
+- Nutze IMMER getEventsInRange um Events zu laden, wenn der Benutzer nach Terminen fragt
+- Nutze searchEvents um nach Terminen per Titel zu suchen (gibt auch die Event-ID zurück)
+- Beispiel: "Was habe ich heute?" → getEventsInRange für heute
+- Beispiel: "Was habe ich diese Woche?" → getEventsInRange für die Woche
+- Beispiel: "Wann ist der Zahnarzt?" → searchEvents mit "Zahnarzt"
+
+WICHTIG - Tool-Verwendung:
+- Du MUSST die proposeCreateEvent/proposeUpdateEvent/proposeDeleteEvent Tools verwenden, um Termine vorzuschlagen!
+- Sage NIEMALS einfach nur "ich habe einen Termin erstellt" ohne das Tool zu verwenden
+- Die Tools erzeugen Karten, die dem Benutzer angezeigt werden - ohne Tool-Aufruf sieht er nichts
+
+WICHTIG - Wiederkehrende Termine (RRULE):
+- Ein wiederkehrendes Event hat EINE FESTE Start- und Endzeit
+- RRULE bestimmt NUR an welchen Tagen das Event wiederholt wird, NICHT unterschiedliche Uhrzeiten pro Tag!
+- Wenn der Benutzer UNTERSCHIEDLICHE ZEITEN an verschiedenen Tagen will, MUSST du SEPARATE Events erstellen
+- Beispiel: "Arbeit Mo+Do 9-17:30, Fr 9-13" → ZWEI Events:
+  1. "Arbeit" Mo+Do 9:00-17:30 (RRULE mit BYDAY=MO,TH)
+  2. "Arbeit" Fr 9:00-13:00 (RRULE mit BYDAY=FR)
+- Nutze NIEMALS BYHOUR/BYMINUTE in RRULE - diese überschreiben die Startzeit nicht wie erwartet!
+- Gültige RRULE-Optionen: FREQ (DAILY/WEEKLY/MONTHLY/YEARLY), BYDAY (MO,TU,WE,TH,FR,SA,SU), INTERVAL, COUNT, UNTIL
+- UNTIL Format: YYYYMMDDTHHMMSSZ (UTC) z.B. UNTIL=20260310T000000Z
+- WICHTIG: Schreibe die RRULE NIEMALS in das description-Feld! Nutze IMMER das recurrenceRule-Feld!
+
+WICHTIG - Antwortformat:
+- Verwende kontextbezogene Antworten in der GEGENWARTSFORM je nach Aktion:
+  - Bei Termin-Erstellung: "Ich schlage folgenden Termin vor:" oder "Neuer Termin:"
+  - Bei Termin-Änderung: "Ich schlage folgende Änderung vor:" oder "Änderung:"
+  - Bei Termin-Löschung: "Ich schlage vor, diesen Termin zu löschen:" oder "Löschung:"
+- WICHTIG: Verwende NIEMALS Vergangenheitsform wie "Ich habe ... vorgeschlagen" - immer Gegenwartsform!
+
+WICHTIG - Unterscheide zwischen PROPOSALS und ABFRAGEN:
+1. Bei PROPOSALS (proposeCreateEvent/proposeUpdateEvent/proposeDeleteEvent):
+   - Halte deine Textantworten SEHR KURZ (1-2 Sätze)
+   - Die Event-Details werden automatisch in Karten angezeigt
+   - Wiederhole NICHT die Details im Text
+2. Bei ABFRAGEN (searchEvents, getEventsInRange, oder Fragen zu existierenden Terminen):
+   - Du MUSST die gefundenen Termine im Text nennen!
+   - Liste die relevanten Termine mit Titel, Datum und Uhrzeit auf
+   - NIEMALS Event-IDs dem Benutzer zeigen! Die IDs sind nur für dich intern
+   - Wenn keine Termine gefunden wurden, sage das explizit (z.B. "In diesem Zeitraum hast du keine Termine.")
+   - Beispiel: "Heute hast du: Zahnarzt um 10:00 Uhr, Meeting um 14:00 Uhr."`;
 }

apps/server/src/ai/utils/toolDefinitions.ts

@@ -94,10 +94,6 @@ export const TOOL_DEFINITIONS: ToolDefinition[] = [
           type: "string",
           description: "Optional event description",
         },
-        isRecurring: {
-          type: "boolean",
-          description: "Whether this is a recurring event",
-        },
         recurrenceRule: {
           type: "string",
           description: "RRULE format string for recurring events",
@@ -131,7 +127,12 @@ export const TOOL_DEFINITIONS: ToolDefinition[] = [
         },
         description: {
           type: "string",
-          description: "New description (optional)",
+          description: "New description (optional). NEVER put RRULE here!",
+        },
+        recurrenceRule: {
+          type: "string",
+          description:
+            "RRULE format string (optional). Use to add UNTIL or modify recurrence. Format: FREQ=DAILY;UNTIL=20260310T000000Z",
         },
       },
       required: ["eventId"],
@@ -140,7 +141,7 @@ export const TOOL_DEFINITIONS: ToolDefinition[] = [
   {
     name: "proposeDeleteEvent",
     description:
-      "Propose deleting an event. The user must confirm. Use this when the user wants to remove an appointment.",
+      "Propose deleting an event. The user must confirm. Use this when the user wants to remove an appointment. For recurring events, specify deleteMode to control which occurrences to delete.",
     parameters: {
       type: "object",
       properties: {
@@ -148,6 +149,17 @@ export const TOOL_DEFINITIONS: ToolDefinition[] = [
           type: "string",
           description: "ID of the event to delete",
         },
+        deleteMode: {
+          type: "string",
+          enum: ["single", "future", "all"],
+          description:
+            "For recurring events: 'single' = only this occurrence, 'future' = this and all future, 'all' = entire recurring event. Defaults to 'all' for non-recurring events.",
+        },
+        occurrenceDate: {
+          type: "string",
+          description:
+            "ISO date string (YYYY-MM-DD) of the specific occurrence to delete. Required for 'single' and 'future' modes.",
+        },
       },
       required: ["eventId"],
     },
@@ -167,4 +179,23 @@ export const TOOL_DEFINITIONS: ToolDefinition[] = [
       required: ["query"],
     },
   },
+  {
+    name: "getEventsInRange",
+    description:
+      "Load events from a specific date range. Use this when the user asks about a time period beyond the default 4 weeks (e.g., 'birthdays in the next 6 months', 'what do I have planned for summer').",
+    parameters: {
+      type: "object",
+      properties: {
+        startDate: {
+          type: "string",
+          description: "Start date as ISO string (YYYY-MM-DD)",
+        },
+        endDate: {
+          type: "string",
+          description: "End date as ISO string (YYYY-MM-DD)",
+        },
+      },
+      required: ["startDate", "endDate"],
+    },
+  },
 ];

apps/server/src/ai/utils/toolExecutor.ts

@@ -3,27 +3,46 @@ import {
   getDay,
   Day,
   DAY_TO_GERMAN,
-} from "@caldav/shared";
+  RecurringDeleteMode,
+} from "@calchat/shared";
 import { AIContext } from "../../services/interfaces";
-import { formatDate, formatTime, formatDateTime } from "./eventFormatter";
+import { formatDate, formatTime, formatDateTime } from "@calchat/shared";
+
+/**
+ * Check if two time ranges overlap.
+ */
+function hasTimeOverlap(
+  start1: Date,
+  end1: Date,
+  start2: Date,
+  end2: Date,
+): boolean {
+  return start1 < end2 && end1 > start2;
+}
+
+/**
+ * Proposed change without ID - ID is added by GPTAdapter when collecting proposals
+ */
+type ToolProposedChange = Omit<ProposedEventChange, "id" | "respondedAction">;
 
 /**
  * Result of executing a tool call.
  */
 export interface ToolResult {
   content: string;
-  proposedChange?: ProposedEventChange;
+  proposedChange?: ToolProposedChange;
 }
 
 /**
  * Execute a tool call and return the result.
  * This function is provider-agnostic and can be used with any LLM.
+ * Async to support tools that need to fetch data (e.g., getEventsInRange).
  */
-export function executeToolCall(
+export async function executeToolCall(
   name: string,
   args: Record<string, unknown>,
   context: AIContext,
-): ToolResult {
+): Promise<ToolResult> {
   switch (name) {
     case "getDay": {
       const date = getDay(
@@ -51,26 +70,57 @@ export function executeToolCall(
         startTime: new Date(args.startTime as string),
         endTime: new Date(args.endTime as string),
         description: args.description as string | undefined,
-        isRecurring: args.isRecurring as boolean | undefined,
         recurrenceRule: args.recurrenceRule as string | undefined,
       };
       const dateStr = formatDate(event.startTime);
       const startStr = formatTime(event.startTime);
       const endStr = formatTime(event.endTime);
+
+      // Check for conflicts - fetch events for the specific day
+      const dayStart = new Date(event.startTime);
+      dayStart.setHours(0, 0, 0, 0);
+      const dayEnd = new Date(dayStart);
+      dayEnd.setDate(dayStart.getDate() + 1);
+
+      const dayEvents = await context.fetchEventsInRange(dayStart, dayEnd);
+
+      // Use occurrenceStart/occurrenceEnd for expanded recurring events
+      const conflicts = dayEvents.filter((e) =>
+        hasTimeOverlap(
+          event.startTime,
+          event.endTime,
+          new Date(e.occurrenceStart),
+          new Date(e.occurrenceEnd),
+        ),
+      );
+
+      // Build conflict warning if any
+      let conflictWarning = "";
+      if (conflicts.length > 0) {
+        const conflictNames = conflicts.map((c) => `"${c.title}"`).join(", ");
+        conflictWarning = `\n⚠️ ACHTUNG: Zeitkonflikt mit ${conflictNames}!`;
+      }
+
       return {
-        content: `Event-Vorschlag erstellt: "${event.title}" am ${dateStr} von ${startStr} bis ${endStr} Uhr`,
+        content: `Event-Vorschlag erstellt: "${event.title}" am ${dateStr} von ${startStr} bis ${endStr} Uhr${conflictWarning}`,
         proposedChange: {
           action: "create",
           event,
+          conflictingEvents:
+            conflicts.length > 0
+              ? conflicts.map((c) => ({
+                  title: c.title,
+                  startTime: new Date(c.occurrenceStart),
+                  endTime: new Date(c.occurrenceEnd),
+                }))
+              : undefined,
         },
       };
     }
 
     case "proposeUpdateEvent": {
       const eventId = args.eventId as string;
-      const existingEvent = context.existingEvents.find(
+      const existingEvent = await context.fetchEventById(eventId);
-        (e) => e.id === eventId,
-      );
 
       if (!existingEvent) {
         return { content: `Event mit ID ${eventId} nicht gefunden.` };
@@ -82,6 +132,7 @@ export function executeToolCall(
         updates.startTime = new Date(args.startTime as string);
       if (args.endTime) updates.endTime = new Date(args.endTime as string);
       if (args.description) updates.description = args.description;
+      if (args.recurrenceRule) updates.recurrenceRule = args.recurrenceRule;
 
       // Build event object for display (merge existing with updates)
       const displayEvent = {
@@ -90,7 +141,9 @@ export function executeToolCall(
         endTime: (updates.endTime as Date) || existingEvent.endTime,
         description:
           (updates.description as string) || existingEvent.description,
-        isRecurring: existingEvent.isRecurring,
+        recurrenceRule:
+          (updates.recurrenceRule as string) || existingEvent.recurrenceRule,
+        exceptionDates: existingEvent.exceptionDates,
       };
 
       return {
@@ -106,16 +159,32 @@ export function executeToolCall(
 
     case "proposeDeleteEvent": {
       const eventId = args.eventId as string;
-      const existingEvent = context.existingEvents.find(
+      const deleteMode = (args.deleteMode as RecurringDeleteMode) || "all";
-        (e) => e.id === eventId,
+      const occurrenceDate = args.occurrenceDate as string | undefined;
-      );
+      const existingEvent = await context.fetchEventById(eventId);
 
       if (!existingEvent) {
         return { content: `Event mit ID ${eventId} nicht gefunden.` };
       }
 
+      // Build descriptive content based on delete mode
+      let modeDescription = "";
+      if (existingEvent.recurrenceRule) {
+        switch (deleteMode) {
+          case "single":
+            modeDescription = " (nur dieses Vorkommen)";
+            break;
+          case "future":
+            modeDescription = " (dieses und alle zukünftigen Vorkommen)";
+            break;
+          case "all":
+            modeDescription = " (alle Vorkommen)";
+            break;
+        }
+      }
+
       return {
-        content: `Lösch-Vorschlag für "${existingEvent.title}" erstellt.`,
+        content: `Lösch-Vorschlag für "${existingEvent.title}"${modeDescription} erstellt.`,
         proposedChange: {
           action: "delete",
           eventId,
@@ -124,32 +193,58 @@ export function executeToolCall(
             startTime: existingEvent.startTime,
             endTime: existingEvent.endTime,
             description: existingEvent.description,
-            isRecurring: existingEvent.isRecurring,
+            recurrenceRule: existingEvent.recurrenceRule,
+            exceptionDates: existingEvent.exceptionDates,
           },
+          deleteMode: existingEvent.recurrenceRule ? deleteMode : undefined,
+          occurrenceDate: existingEvent.recurrenceRule
+            ? occurrenceDate
+            : undefined,
         },
       };
     }
 
     case "searchEvents": {
-      const query = (args.query as string).toLowerCase();
+      const query = args.query as string;
-      const matches = context.existingEvents.filter((e) =>
+      const matches = await context.searchEvents(query);
-        e.title.toLowerCase().includes(query),
-      );
 
       if (matches.length === 0) {
-        return { content: `Keine Termine mit "${args.query}" gefunden.` };
+        return { content: `Keine Termine mit "${query}" gefunden.` };
       }
 
       const results = matches
         .map((e) => {
           const start = new Date(e.startTime);
-          return `- ${e.title} (ID: ${e.id}) am ${formatDate(start)} um ${formatTime(start)} Uhr`;
+          const recurrenceInfo = e.recurrenceRule ? " (wiederkehrend)" : "";
+          return `- ${e.title} (ID: ${e.id}) am ${formatDate(start)} um ${formatTime(start)} Uhr${recurrenceInfo}`;
         })
         .join("\n");
 
       return { content: `Gefundene Termine:\n${results}` };
     }
 
+    case "getEventsInRange": {
+      const startDate = new Date(args.startDate as string);
+      const endDate = new Date(args.endDate as string);
+      const events = await context.fetchEventsInRange(startDate, endDate);
+
+      if (events.length === 0) {
+        return { content: "Keine Termine in diesem Zeitraum." };
+      }
+
+      const eventsText = events
+        .map((e) => {
+          const start = new Date(e.occurrenceStart);
+          const recurrenceInfo = e.recurrenceRule ? " (wiederkehrend)" : "";
+          return `- ${e.title} (ID: ${e.id}) am ${formatDate(start)} um ${formatTime(start)} Uhr${recurrenceInfo}`;
+        })
+        .join("\n");
+
+      return {
+        content: `Termine von ${formatDate(startDate)} bis ${formatDate(endDate)}:\n${eventsText}`,
+      };
+    }
+
     default:
       return { content: `Unbekannte Funktion: ${name}` };
   }

apps/server/src/app.ts

@@ -3,7 +3,12 @@ import mongoose from "mongoose";
 import "dotenv/config";
 
 import { createRoutes } from "./routes";
-import { AuthController, ChatController, EventController } from "./controllers";
+import {
+  AuthController,
+  ChatController,
+  EventController,
+  httpLogger,
+} from "./controllers";
 import { AuthService, ChatService, EventService } from "./services";
 import {
   MongoUserRepository,
@@ -11,13 +16,18 @@ import {
   MongoChatRepository,
 } from "./repositories";
 import { GPTAdapter } from "./ai";
+import { logger } from "./logging";
+import { MongoCaldavRepository } from "./repositories/mongo/MongoCaldavRepository";
+import { CaldavService } from "./services/CaldavService";
+import { CaldavController } from "./controllers/CaldavController";
 
 const app = express();
 const port = process.env.PORT || 3000;
-const mongoUri = process.env.MONGODB_URI || "mongodb://localhost:27017/caldav";
+const mongoUri = process.env.MONGODB_URI || "mongodb://localhost:27017/calchat";
 
 // Middleware
 app.use(express.json());
+app.use(httpLogger);
 
 // CORS - only needed for web browser development
 // Native mobile apps don't send Origin headers and aren't affected by CORS
@@ -28,7 +38,10 @@ if (process.env.NODE_ENV !== "production") {
       "Access-Control-Allow-Methods",
       "GET, POST, PUT, DELETE, OPTIONS",
     );
-    res.header("Access-Control-Allow-Headers", "Content-Type, Authorization");
+    res.header(
+      "Access-Control-Allow-Headers",
+      "Content-Type, Authorization, X-User-Id",
+    );
     if (req.method === "OPTIONS") {
       res.sendStatus(200);
       return;
@@ -41,19 +54,22 @@ if (process.env.NODE_ENV !== "production") {
 const userRepo = new MongoUserRepository();
 const eventRepo = new MongoEventRepository();
 const chatRepo = new MongoChatRepository();
+const caldavRepo = new MongoCaldavRepository();
 
 // Initialize AI provider
 const aiProvider = new GPTAdapter();
 
 // Initialize services
 const authService = new AuthService(userRepo);
-const chatService = new ChatService(chatRepo, eventRepo, aiProvider);
 const eventService = new EventService(eventRepo);
+const caldavService = new CaldavService(caldavRepo, eventService);
+const chatService = new ChatService(chatRepo, eventService, aiProvider);
 
 // Initialize controllers
 const authController = new AuthController(authService);
-const chatController = new ChatController(chatService);
+const chatController = new ChatController(chatService, caldavService);
-const eventController = new EventController(eventService);
+const eventController = new EventController(eventService, caldavService);
+const caldavController = new CaldavController(caldavService);
 
 // Setup routes
 app.use(
@@ -62,6 +78,7 @@ app.use(
     authController,
     chatController,
     eventController,
+    caldavController,
   }),
 );
 
@@ -81,12 +98,14 @@ app.post("/api/ai/test", async (req, res) => {
     const result = await aiProvider.processMessage(message, {
       userId: "test-user",
       conversationHistory: [],
-      existingEvents: [],
       currentDate: new Date(),
+      fetchEventsInRange: async () => [],
+      searchEvents: async () => [],
+      fetchEventById: async () => null,
     });
     res.json(result);
   } catch (error) {
-    console.error("AI test error:", error);
+    logger.error({ error }, "AI test error");
     res.status(500).json({ error: String(error) });
   }
 });
@@ -95,13 +114,13 @@ app.post("/api/ai/test", async (req, res) => {
 async function start() {
   try {
     await mongoose.connect(mongoUri);
-    console.log("Connected to MongoDB");
+    logger.info("Connected to MongoDB");
 
     app.listen(port, () => {
-      console.log(`Server running on port ${port}`);
+      logger.info({ port }, "Server started");
     });
   } catch (error) {
-    console.error("Failed to start server:", error);
+    logger.fatal({ error }, "Failed to start server");
     process.exit(1);
   }
 }

apps/server/src/controllers/AuthController.ts

@@ -21,12 +21,4 @@ export class AuthController {
       res.status(400).json({ error: (error as Error).message });
     }
   }
-
-  async refresh(req: Request, res: Response): Promise<void> {
-    throw new Error("Not implemented");
-  }
-
-  async logout(req: Request, res: Response): Promise<void> {
-    throw new Error("Not implemented");
-  }
 }

apps/server/src/controllers/AuthMiddleware.ts

@@ -0,0 +1,25 @@
+import { Request, Response, NextFunction } from "express";
+
+export interface AuthenticatedUser {
+  userId: string;
+}
+
+export interface AuthenticatedRequest extends Request {
+  user?: AuthenticatedUser;
+}
+
+export function authenticate(
+  req: AuthenticatedRequest,
+  res: Response,
+  next: NextFunction,
+): void {
+  const userId = req.headers["x-user-id"];
+
+  if (!userId || typeof userId !== "string") {
+    res.status(401).json({ error: "Unauthorized" });
+    return;
+  }
+
+  req.user = { userId };
+  next();
+}

apps/server/src/controllers/CaldavController.ts

@@ -0,0 +1,103 @@
+import { Response } from "express";
+import { createLogger } from "../logging/logger";
+import { AuthenticatedRequest } from "./AuthMiddleware";
+import { CaldavConfig } from "@calchat/shared";
+import { CaldavService } from "../services/CaldavService";
+
+const log = createLogger("CaldavController");
+
+export class CaldavController {
+  constructor(private caldavService: CaldavService) {}
+
+  async saveConfig(req: AuthenticatedRequest, res: Response): Promise<void> {
+    try {
+      const config: CaldavConfig = { userId: req.user!.userId, ...req.body };
+      const response = await this.caldavService.saveConfig(config);
+      res.json(response);
+    } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error saving config",
+      );
+      res.status(500).json({ error: "Failed to save config" });
+    }
+  }
+
+  async loadConfig(req: AuthenticatedRequest, res: Response): Promise<void> {
+    try {
+      const config = await this.caldavService.getConfig(req.user!.userId);
+      if (!config) {
+        res.status(404).json({ error: "No CalDAV config found" });
+        return;
+      }
+      // Don't expose the password to the client
+      res.json(config);
+    } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error loading config",
+      );
+      res.status(500).json({ error: "Failed to load config" });
+    }
+  }
+
+  async deleteConfig(req: AuthenticatedRequest, res: Response): Promise<void> {
+    try {
+      await this.caldavService.deleteConfig(req.user!.userId);
+      res.status(204).send();
+    } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error deleting config",
+      );
+      res.status(500).json({ error: "Failed to delete config" });
+    }
+  }
+
+  async pullEvents(req: AuthenticatedRequest, res: Response): Promise<void> {
+    try {
+      const events = await this.caldavService.pullEvents(req.user!.userId);
+      res.json(events);
+    } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error pulling events",
+      );
+      res.status(500).json({ error: "Failed to pull events" });
+    }
+  }
+
+  async pushEvents(req: AuthenticatedRequest, res: Response): Promise<void> {
+    try {
+      await this.caldavService.pushAll(req.user!.userId);
+      res.status(204).send();
+    } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error pushing events",
+      );
+      res.status(500).json({ error: "Failed to push events" });
+    }
+  }
+
+  async pushEvent(req: AuthenticatedRequest, res: Response): Promise<void> {
+    try {
+      const event = await this.caldavService.findEventByCaldavUUID(
+        req.user!.userId,
+        req.params.caldavUUID,
+      );
+      if (!event) {
+        res.status(404).json({ error: "Event not found" });
+        return;
+      }
+      await this.caldavService.pushEvent(req.user!.userId, event);
+      res.status(204).send();
+    } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error pushing event",
+      );
+      res.status(500).json({ error: "Failed to push event" });
+    }
+  }
+}

apps/server/src/controllers/ChatController.ts

@@ -5,12 +5,20 @@ import {
   UpdateEventDTO,
   EventAction,
   GetMessagesOptions,
-} from "@caldav/shared";
+  RecurringDeleteMode,
+} from "@calchat/shared";
 import { ChatService } from "../services";
-import { AuthenticatedRequest } from "../middleware";
+import { CaldavService } from "../services/CaldavService";
+import { createLogger } from "../logging";
+import { AuthenticatedRequest } from "./AuthMiddleware";
+
+const log = createLogger("ChatController");
 
 export class ChatController {
-  constructor(private chatService: ChatService) {}
+  constructor(
+    private chatService: ChatService,
+    private caldavService: CaldavService,
+  ) {}
 
   async sendMessage(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
@@ -19,6 +27,10 @@ export class ChatController {
       const response = await this.chatService.processMessage(userId, data);
       res.json(response);
     } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error processing message",
+      );
       res.status(500).json({ error: "Failed to process message" });
     }
   }
@@ -27,23 +39,55 @@ export class ChatController {
     try {
       const userId = req.user!.userId;
       const { conversationId, messageId } = req.params;
-      const { action, event, eventId, updates } = req.body as {
+
+      // DEBUG: Log incoming request body to trace deleteMode issue
+      log.debug({ body: req.body }, "confirmEvent request body");
+
+      const {
+        proposalId,
+        action,
+        event,
+        eventId,
+        updates,
+        deleteMode,
+        occurrenceDate,
+      } = req.body as {
+        proposalId: string;
         action: EventAction;
         event?: CreateEventDTO;
         eventId?: string;
         updates?: UpdateEventDTO;
+        deleteMode?: RecurringDeleteMode;
+        occurrenceDate?: string;
       };
       const response = await this.chatService.confirmEvent(
         userId,
         conversationId,
         messageId,
+        proposalId,
         action,
         event,
         eventId,
         updates,
+        deleteMode,
+        occurrenceDate,
       );
+
+      // Sync confirmed event to CalDAV
+      try {
+        if (await this.caldavService.getConfig(userId)) {
+          await this.caldavService.pushAll(userId);
+        }
+      } catch (error) {
+        log.error({ err: error, userId }, "CalDAV push after confirm failed");
+      }
+
       res.json(response);
     } catch (error) {
+      log.error(
+        { err: error, conversationId: req.params.conversationId },
+        "Error confirming event",
+      );
       res.status(500).json({ error: "Failed to confirm event" });
     }
   }
@@ -52,13 +96,19 @@ export class ChatController {
     try {
       const userId = req.user!.userId;
       const { conversationId, messageId } = req.params;
+      const { proposalId } = req.body as { proposalId: string };
       const response = await this.chatService.rejectEvent(
         userId,
         conversationId,
         messageId,
+        proposalId,
       );
       res.json(response);
     } catch (error) {
+      log.error(
+        { err: error, conversationId: req.params.conversationId },
+        "Error rejecting event",
+      );
       res.status(500).json({ error: "Failed to reject event" });
     }
   }
@@ -72,6 +122,10 @@ export class ChatController {
       const conversations = await this.chatService.getConversations(userId);
       res.json(conversations);
     } catch (error) {
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error getting conversations",
+      );
       res.status(500).json({ error: "Failed to get conversations" });
     }
   }
@@ -102,8 +156,41 @@ export class ChatController {
       if ((error as Error).message === "Conversation not found") {
         res.status(404).json({ error: "Conversation not found" });
       } else {
+        log.error(
+          { err: error, conversationId: req.params.id },
+          "Error getting conversation",
+        );
         res.status(500).json({ error: "Failed to get conversation" });
       }
     }
   }
+
+  async updateProposalEvent(
+    req: AuthenticatedRequest,
+    res: Response,
+  ): Promise<void> {
+    try {
+      const { messageId } = req.params;
+      const { proposalId, event } = req.body as {
+        proposalId: string;
+        event: CreateEventDTO;
+      };
+      const message = await this.chatService.updateProposalEvent(
+        messageId,
+        proposalId,
+        event,
+      );
+      if (message) {
+        res.json(message);
+      } else {
+        res.status(404).json({ error: "Message or proposal not found" });
+      }
+    } catch (error) {
+      log.error(
+        { err: error, messageId: req.params.messageId },
+        "Error updating proposal event",
+      );
+      res.status(500).json({ error: "Failed to update proposal event" });
+    }
+  }
 }

apps/server/src/controllers/EventController.ts

@@ -1,16 +1,49 @@
 import { Response } from "express";
+import { CalendarEvent, RecurringDeleteMode } from "@calchat/shared";
 import { EventService } from "../services";
-import { AuthenticatedRequest } from "../middleware";
+import { createLogger } from "../logging";
+import { AuthenticatedRequest } from "./AuthMiddleware";
+import { CaldavService } from "../services/CaldavService";
+
+const log = createLogger("EventController");
 
 export class EventController {
-  constructor(private eventService: EventService) {}
+  constructor(
+    private eventService: EventService,
+    private caldavService: CaldavService,
+  ) {}
+
+  private async pushToCaldav(userId: string, event: CalendarEvent) {
+    if (await this.caldavService.getConfig(userId)) {
+      try {
+        await this.caldavService.pushEvent(userId, event);
+      } catch (error) {
+        log.error({ err: error, userId }, "Error pushing event to CalDAV");
+      }
+    }
+  }
+
+  private async deleteFromCaldav(userId: string, event: CalendarEvent) {
+    if (event.caldavUUID && (await this.caldavService.getConfig(userId))) {
+      try {
+        await this.caldavService.deleteEvent(userId, event.caldavUUID);
+      } catch (error) {
+        log.error({ err: error, userId }, "Error deleting event from CalDAV");
+      }
+    }
+  }
 
   async create(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
-      const event = await this.eventService.create(req.user!.userId, req.body);
+      const userId = req.user!.userId;
+      const event = await this.eventService.create(userId, req.body);
+      await this.pushToCaldav(userId, event);
       res.status(201).json(event);
     } catch (error) {
-      console.error("Error creating event:", error);
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error creating event",
+      );
       res.status(500).json({ error: "Failed to create event" });
     }
   }
@@ -27,7 +60,7 @@ export class EventController {
       }
       res.json(event);
     } catch (error) {
-      console.error("Error getting event:", error);
+      log.error({ err: error, eventId: req.params.id }, "Error getting event");
       res.status(500).json({ error: "Failed to get event" });
     }
   }
@@ -37,7 +70,10 @@ export class EventController {
       const events = await this.eventService.getAll(req.user!.userId);
       res.json(events);
     } catch (error) {
-      console.error("Error getting events:", error);
+      log.error(
+        { err: error, userId: req.user?.userId },
+        "Error getting events",
+      );
       res.status(500).json({ error: "Failed to get events" });
     }
   }
@@ -69,42 +105,79 @@ export class EventController {
       );
       res.json(events);
     } catch (error) {
-      console.error("Error getting events by range:", error);
+      log.error(
+        { err: error, start: req.query.start, end: req.query.end },
+        "Error getting events by range",
+      );
       res.status(500).json({ error: "Failed to get events" });
     }
   }
 
   async update(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
+      const userId = req.user!.userId;
       const event = await this.eventService.update(
         req.params.id,
-        req.user!.userId,
+        userId,
         req.body,
       );
       if (!event) {
         res.status(404).json({ error: "Event not found" });
         return;
       }
+
+      await this.pushToCaldav(userId, event);
+
       res.json(event);
     } catch (error) {
-      console.error("Error updating event:", error);
+      log.error({ err: error, eventId: req.params.id }, "Error updating event");
       res.status(500).json({ error: "Failed to update event" });
     }
   }
 
   async delete(req: AuthenticatedRequest, res: Response): Promise<void> {
     try {
-      const deleted = await this.eventService.delete(
+      const userId = req.user!.userId;
-        req.params.id,
+      const { mode, occurrenceDate } = req.query as {
-        req.user!.userId,
+        mode?: RecurringDeleteMode;
-      );
+        occurrenceDate?: string;
-      if (!deleted) {
+      };
+
+      // Fetch event before deletion to get caldavUUID for sync
+      const event = await this.eventService.getById(req.params.id, userId);
+      if (!event) {
         res.status(404).json({ error: "Event not found" });
         return;
       }
+
+      // If mode is specified, use deleteRecurring
+      if (mode) {
+        const result = await this.eventService.deleteRecurring(
+          req.params.id,
+          userId,
+          mode,
+          occurrenceDate,
+        );
+
+        // Event was updated (single/future mode) - push update to CalDAV
+        if (result) {
+          await this.pushToCaldav(userId, result);
+          res.json(result);
+          return;
+        }
+
+        // Event was fully deleted (all mode, or future from first occurrence)
+        await this.deleteFromCaldav(userId, event);
+        res.status(204).send();
+        return;
+      }
+
+      // Default behavior: delete completely
+      await this.eventService.delete(req.params.id, userId);
+      await this.deleteFromCaldav(userId, event);
       res.status(204).send();
     } catch (error) {
-      console.error("Error deleting event:", error);
+      log.error({ err: error, eventId: req.params.id }, "Error deleting event");
       res.status(500).json({ error: "Failed to delete event" });
     }
   }

apps/server/src/controllers/LoggingMiddleware.ts

@@ -0,0 +1,27 @@
+import pinoHttp from "pino-http";
+import { logger } from "../logging";
+
+export const httpLogger = pinoHttp({
+  logger,
+  customLogLevel: (_req, res, err) => {
+    if (res.statusCode >= 500 || err) return "error";
+    if (res.statusCode >= 400) return "warn";
+    return "info";
+  },
+  customSuccessMessage: (req, res) => {
+    return `${req.method} ${req.url} ${res.statusCode}`;
+  },
+  customErrorMessage: (req, _res, err) => {
+    return `${req.method} ${req.url} failed: ${err.message}`;
+  },
+  redact: ["req.headers.authorization"],
+  serializers: {
+    req: (req) => ({
+      method: req.method,
+      url: req.url,
+    }),
+    res: (res) => ({
+      statusCode: res.statusCode,
+    }),
+  },
+});

apps/server/src/controllers/index.ts

@@ -1,3 +1,6 @@
 export * from "./AuthController";
 export * from "./ChatController";
 export * from "./EventController";
+export * from "./AuthMiddleware";
+export * from "./LoggingMiddleware";
+export * from "./CaldavController";

apps/server/src/logging/Logged.ts

@@ -0,0 +1,129 @@
+import { createLogger } from "./logger";
+
+/**
+ * Summarize args for logging to avoid huge log entries.
+ * - Arrays: show length only
+ * - Long strings: truncate
+ * - Objects with conversationHistory: summarize
+ */
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+function summarizeArgs(args: any[]): any[] {
+  return args.map((arg) => summarizeValue(arg));
+}
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+function summarizeValue(value: any, depth = 0): any {
+  if (depth > 2) return "[...]";
+
+  if (value === null || value === undefined) return value;
+
+  if (Array.isArray(value)) {
+    return `[Array(${value.length})]`;
+  }
+
+  if (typeof value === "string" && value.length > 100) {
+    return value.substring(0, 100) + "...";
+  }
+
+  if (typeof value === "object") {
+    // Summarize known large fields
+    const summarized: Record<string, unknown> = {};
+    for (const [key, val] of Object.entries(value)) {
+      if (key === "conversationHistory" && Array.isArray(val)) {
+        summarized[key] = `[${val.length} messages]`;
+      } else if (key === "proposedChanges" && Array.isArray(val)) {
+        // Log full proposedChanges for debugging AI issues
+        summarized[key] = val.map((p) => summarizeValue(p, depth + 1));
+      } else if (Array.isArray(val)) {
+        summarized[key] = `[Array(${val.length})]`;
+      } else if (typeof val === "object" && val !== null) {
+        summarized[key] = summarizeValue(val, depth + 1);
+      } else if (typeof val === "string" && val.length > 100) {
+        summarized[key] = val.substring(0, 100) + "...";
+      } else {
+        summarized[key] = val;
+      }
+    }
+    return summarized;
+  }
+
+  return value;
+}
+
+export function Logged(name: string) {
+  const log = createLogger(name);
+
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  return function <T extends { new (...args: any[]): any }>(Constructor: T) {
+    return class extends Constructor {
+      // eslint-disable-next-line @typescript-eslint/no-explicit-any
+      constructor(...args: any[]) {
+        super(...args);
+
+        // Return a Proxy that intercepts method calls lazily
+        return new Proxy(this, {
+          get(target, propKey, receiver) {
+            const original = Reflect.get(target, propKey, receiver);
+
+            if (typeof original !== "function" || propKey === "constructor") {
+              return original;
+            }
+
+            // eslint-disable-next-line @typescript-eslint/no-explicit-any
+            const originalFn = original as (...args: any[]) => any;
+
+            // eslint-disable-next-line @typescript-eslint/no-explicit-any
+            return function (this: any, ...methodArgs: any[]) {
+              const start = performance.now();
+              const method = String(propKey);
+
+              // Summarize args to avoid huge log entries
+              log.debug(
+                { method, args: summarizeArgs(methodArgs) },
+                `${method} started`,
+              );
+
+              const logCompletion = (err?: unknown) => {
+                const duration = Math.round(performance.now() - start);
+                if (err) {
+                  const message =
+                    err instanceof Error ? err.message : String(err);
+                  log.error(
+                    { method, duration, error: message },
+                    `${method} failed`,
+                  );
+                } else {
+                  log.info({ method, duration }, `${method} completed`);
+                }
+              };
+
+              try {
+                const result = originalFn.apply(this, methodArgs);
+
+                // Check if async - preserves sync/async nature of method
+                if (result instanceof Promise) {
+                  return result
+                    .then((val) => {
+                      logCompletion();
+                      return val;
+                    })
+                    .catch((err) => {
+                      logCompletion(err);
+                      throw err;
+                    });
+                }
+
+                // Synchronous completion
+                logCompletion();
+                return result;
+              } catch (err) {
+                logCompletion(err);
+                throw err;
+              }
+            };
+          },
+        });
+      }
+    };
+  };
+}

apps/server/src/logging/index.ts

@@ -0,0 +1,2 @@
+export { logger, createLogger, type Logger } from "./logger";
+export { Logged } from "./Logged";

apps/server/src/logging/logger.ts

@@ -0,0 +1,43 @@
+import pino from "pino";
+
+const isDevelopment = process.env.NODE_ENV !== "production";
+
+export const logger = pino({
+  level: process.env.LOG_LEVEL || (isDevelopment ? "debug" : "info"),
+  redact: {
+    paths: [
+      // Root level
+      "password",
+      "passwordHash",
+      "token",
+      // One level deep (e.g. user.password)
+      "*.password",
+      "*.passwordHash",
+      "*.token",
+      // In arrays (for 'args' in decorator)
+      "args[*].password",
+      "args[*].passwordHash",
+      "args[*].token",
+    ],
+    censor: "[REDACTED]",
+  },
+  transport: isDevelopment
+    ? {
+        target: "pino-pretty",
+        options: {
+          colorize: true,
+          translateTime: "SYS:HH:MM:ss",
+          ignore: "pid,hostname",
+        },
+      }
+    : undefined,
+  base: {
+    service: "calchat-server",
+  },
+});
+
+export function createLogger(module: string) {
+  return logger.child({ module });
+}
+
+export type Logger = pino.Logger;

apps/server/src/middleware/AuthMiddleware.ts

@@ -1,20 +0,0 @@
-import { Request, Response, NextFunction } from "express";
-import { verifyToken, TokenPayload } from "../utils/jwt";
-
-export interface AuthenticatedRequest extends Request {
-  user?: TokenPayload;
-}
-
-export function authenticate(
-  req: AuthenticatedRequest,
-  res: Response,
-  next: NextFunction,
-): void {
-  // TODO: Implement real JWT verification
-  // Fake user for testing purposes
-  req.user = {
-    userId: "fake-user-id",
-    email: "test@example.com",
-  };
-  next();
-}

apps/server/src/middleware/index.ts

@@ -1 +0,0 @@
-export * from "./AuthMiddleware";

apps/server/src/repositories/mongo/MongoCaldavRepository.ts

@@ -0,0 +1,31 @@
+import { CaldavConfig } from "@calchat/shared";
+import { Logged } from "../../logging/Logged";
+import { CaldavRepository } from "../../services/interfaces/CaldavRepository";
+import { CaldavConfigModel } from "./models/CaldavConfigModel";
+
+@Logged("MongoCaldavRepository")
+export class MongoCaldavRepository implements CaldavRepository {
+  async findByUserId(userId: string): Promise<CaldavConfig | null> {
+    const config = await CaldavConfigModel.findOne({ userId });
+    if (!config) return null;
+    return config.toJSON() as unknown as CaldavConfig;
+  }
+
+  async createOrUpdate(config: CaldavConfig): Promise<CaldavConfig> {
+    const caldavConfig = await CaldavConfigModel.findOneAndUpdate(
+      { userId: config.userId },
+      config,
+      {
+        upsert: true,
+        new: true,
+      },
+    );
+    // NOTE: Casting required because Mongoose's toJSON() type doesn't reflect our virtual 'id' field
+    return caldavConfig.toJSON() as unknown as CaldavConfig;
+  }
+
+  async deleteByUserId(userId: string): Promise<boolean> {
+    const result = await CaldavConfigModel.findOneAndDelete({ userId });
+    return result !== null;
+  }
+}

apps/server/src/repositories/mongo/MongoChatRepository.ts

@@ -2,12 +2,16 @@ import {
   ChatMessage,
   Conversation,
   CreateMessageDTO,
+  CreateEventDTO,
   GetMessagesOptions,
   UpdateMessageDTO,
-} from "@caldav/shared";
+  ConflictingEvent,
+} from "@calchat/shared";
 import { ChatRepository } from "../../services/interfaces";
+import { Logged } from "../../logging";
 import { ChatMessageModel, ConversationModel } from "./models";
 
+@Logged("MongoChatRepository")
 export class MongoChatRepository implements ChatRepository {
   // Conversations
   async getConversationsByUser(userId: string): Promise<Conversation[]> {
@@ -22,12 +26,20 @@ export class MongoChatRepository implements ChatRepository {
     return conversation.toJSON() as unknown as Conversation;
   }
 
+  async getConversationById(
+    conversationId: string,
+  ): Promise<Conversation | null> {
+    const conversation = await ConversationModel.findById(conversationId);
+    return conversation
+      ? (conversation.toJSON() as unknown as Conversation)
+      : null;
+  }
+
   // Messages (cursor-based pagination)
   async getMessages(
     conversationId: string,
     options?: GetMessagesOptions,
   ): Promise<ChatMessage[]> {
-    const limit = options?.limit ?? 20;
     const query: Record<string, unknown> = { conversationId };
 
     // Cursor: load messages before this ID (for "load more" scrolling up)
@@ -36,9 +48,12 @@ export class MongoChatRepository implements ChatRepository {
     }
 
     // Fetch newest first, then reverse for chronological order
-    const docs = await ChatMessageModel.find(query)
+    // Only apply limit if explicitly specified (no default - load all messages)
-      .sort({ _id: -1 })
+    let queryBuilder = ChatMessageModel.find(query).sort({ _id: -1 });
-      .limit(limit);
+    if (options?.limit) {
+      queryBuilder = queryBuilder.limit(options.limit);
+    }
+    const docs = await queryBuilder;
 
     return docs.reverse().map((doc) => doc.toJSON() as unknown as ChatMessage);
   }
@@ -51,7 +66,7 @@ export class MongoChatRepository implements ChatRepository {
       conversationId: conversationId,
       sender: message.sender,
       content: message.content,
-      proposedChange: message.proposedChange,
+      proposedChanges: message.proposedChanges,
     });
     return repoMessage.toJSON() as unknown as ChatMessage;
   }
@@ -67,4 +82,46 @@ export class MongoChatRepository implements ChatRepository {
     );
     return doc ? (doc.toJSON() as unknown as ChatMessage) : null;
   }
+
+  async updateProposalResponse(
+    messageId: string,
+    proposalId: string,
+    respondedAction: "confirm" | "reject",
+  ): Promise<ChatMessage | null> {
+    const doc = await ChatMessageModel.findOneAndUpdate(
+      { _id: messageId, "proposedChanges.id": proposalId },
+      { $set: { "proposedChanges.$.respondedAction": respondedAction } },
+      { new: true },
+    );
+    return doc ? (doc.toJSON() as unknown as ChatMessage) : null;
+  }
+
+  async updateProposalEvent(
+    messageId: string,
+    proposalId: string,
+    event: CreateEventDTO,
+    conflictingEvents?: ConflictingEvent[],
+  ): Promise<ChatMessage | null> {
+    // Always set both fields - use empty array when no conflicts
+    // (MongoDB has issues combining $set and $unset on positional operator)
+    const setFields: Record<string, unknown> = {
+      "proposedChanges.$.event": event,
+      "proposedChanges.$.conflictingEvents":
+        conflictingEvents && conflictingEvents.length > 0
+          ? conflictingEvents
+          : [],
+    };
+
+    const doc = await ChatMessageModel.findOneAndUpdate(
+      { _id: messageId, "proposedChanges.id": proposalId },
+      { $set: setFields },
+      { new: true },
+    );
+    return doc ? (doc.toJSON() as unknown as ChatMessage) : null;
+  }
+
+  async getMessageById(messageId: string): Promise<ChatMessage | null> {
+    const doc = await ChatMessageModel.findById(messageId);
+    return doc ? (doc.toJSON() as unknown as ChatMessage) : null;
+  }
 }

apps/server/src/repositories/mongo/MongoEventRepository.ts

@@ -1,7 +1,9 @@
-import { CalendarEvent, CreateEventDTO, UpdateEventDTO } from "@caldav/shared";
+import { CalendarEvent, CreateEventDTO, UpdateEventDTO } from "@calchat/shared";
 import { EventRepository } from "../../services/interfaces";
+import { Logged } from "../../logging";
 import { EventModel } from "./models";
 
+@Logged("MongoEventRepository")
 export class MongoEventRepository implements EventRepository {
   async findById(id: string): Promise<CalendarEvent | null> {
     const event = await EventModel.findById(id);
@@ -26,6 +28,23 @@ export class MongoEventRepository implements EventRepository {
     return events.map((e) => e.toJSON() as unknown as CalendarEvent);
   }
 
+  async findByCaldavUUID(
+    userId: string,
+    caldavUUID: string,
+  ): Promise<CalendarEvent | null> {
+    const event = await EventModel.findOne({ userId, caldavUUID });
+    if (!event) return null;
+    return event.toJSON() as unknown as CalendarEvent;
+  }
+
+  async searchByTitle(userId: string, query: string): Promise<CalendarEvent[]> {
+    const events = await EventModel.find({
+      userId,
+      title: { $regex: query, $options: "i" },
+    }).sort({ startTime: 1 });
+    return events.map((e) => e.toJSON() as unknown as CalendarEvent);
+  }
+
   async create(userId: string, data: CreateEventDTO): Promise<CalendarEvent> {
     const event = await EventModel.create({ userId, ...data });
     // NOTE: Casting required because Mongoose's toJSON() type doesn't reflect our virtual 'id' field
@@ -45,4 +64,17 @@ export class MongoEventRepository implements EventRepository {
     const result = await EventModel.findByIdAndDelete(id);
     return result !== null;
   }
+
+  async addExceptionDate(
+    id: string,
+    date: string,
+  ): Promise<CalendarEvent | null> {
+    const event = await EventModel.findByIdAndUpdate(
+      id,
+      { $addToSet: { exceptionDates: date } },
+      { new: true },
+    );
+    if (!event) return null;
+    return event.toJSON() as unknown as CalendarEvent;
+  }
 }

apps/server/src/repositories/mongo/MongoUserRepository.ts

@@ -1,21 +1,38 @@
-import { User } from "@caldav/shared";
+import { User } from "@calchat/shared";
 import { UserRepository, CreateUserData } from "../../services/interfaces";
-import { UserModel } from "./models";
+import { Logged } from "../../logging";
+import { UserModel, UserDocument } from "./models";
 
+function toUser(doc: UserDocument): User {
+  return {
+    id: doc._id.toString(),
+    email: doc.email,
+    userName: doc.userName,
+    passwordHash: doc.passwordHash,
+    createdAt: doc.createdAt,
+    updatedAt: doc.updatedAt,
+  };
+}
+
+@Logged("MongoUserRepository")
 export class MongoUserRepository implements UserRepository {
   async findById(id: string): Promise<User | null> {
-    throw new Error("Not implemented");
+    const user = await UserModel.findById(id);
+    return user ? toUser(user) : null;
   }
 
   async findByEmail(email: string): Promise<User | null> {
     const user = await UserModel.findOne({ email: email.toLowerCase() });
-    // NOTE: Casting required because Mongoose's toJSON() type doesn't reflect our virtual 'id' field
+    return user ? toUser(user) : null;
-    return (user?.toJSON() as unknown as User) ?? null;
+  }
+
+  async findByUserName(userName: string): Promise<User | null> {
+    const user = await UserModel.findOne({ userName });
+    return user ? toUser(user) : null;
   }
 
   async create(data: CreateUserData): Promise<User> {
     const user = await UserModel.create(data);
-    // NOTE: Casting required because Mongoose's toJSON() type doesn't reflect our virtual 'id' field
+    return toUser(user);
-    return user.toJSON() as unknown as User;
   }
 }

apps/server/src/repositories/mongo/models/CaldavConfigModel.ts

@@ -0,0 +1,22 @@
+import { CaldavConfig } from "@calchat/shared";
+import mongoose, { Document, Schema } from "mongoose";
+
+export interface CaldavConfigDocument extends CaldavConfig, Document {
+  toJSON(): CaldavConfig;
+}
+
+const CaldavConfigSchema = new Schema<CaldavConfigDocument>(
+  {
+    userId: { type: String, required: true, index: true },
+    serverUrl: { type: String, required: true },
+    username: { type: String, required: true },
+    password: { type: String, required: true },
+    syncIntervalSeconds: { type: Number },
+  },
+  { _id: false },
+);
+
+export const CaldavConfigModel = mongoose.model<CaldavConfigDocument>(
+  "CaldavConfig",
+  CaldavConfigSchema,
+);

apps/server/src/repositories/mongo/models/ChatModel.ts

@@ -5,7 +5,8 @@ import {
   CreateEventDTO,
   UpdateEventDTO,
   ProposedEventChange,
-} from "@caldav/shared";
+  ConflictingEvent,
+} from "@calchat/shared";
 import { IdVirtual } from "./types";
 
 export interface ChatMessageDocument extends Omit<ChatMessage, "id">, Document {
@@ -23,8 +24,8 @@ const EventSchema = new Schema<CreateEventDTO>(
     startTime: { type: Date, required: true },
     endTime: { type: Date, required: true },
     note: { type: String },
-    isRecurring: { type: Boolean },
     recurrenceRule: { type: String },
+    exceptionDates: { type: [String] },
   },
   { _id: false },
 );
@@ -36,14 +37,23 @@ const UpdatesSchema = new Schema<UpdateEventDTO>(
     startTime: { type: Date },
     endTime: { type: Date },
     note: { type: String },
-    isRecurring: { type: Boolean },
     recurrenceRule: { type: String },
   },
   { _id: false },
 );
 
+const ConflictingEventSchema = new Schema<ConflictingEvent>(
+  {
+    title: { type: String, required: true },
+    startTime: { type: Date, required: true },
+    endTime: { type: Date, required: true },
+  },
+  { _id: false },
+);
+
 const ProposedChangeSchema = new Schema<ProposedEventChange>(
   {
+    id: { type: String, required: true },
     action: {
       type: String,
       enum: ["create", "update", "delete"],
@@ -52,6 +62,16 @@ const ProposedChangeSchema = new Schema<ProposedEventChange>(
     eventId: { type: String },
     event: { type: EventSchema },
     updates: { type: UpdatesSchema },
+    respondedAction: {
+      type: String,
+      enum: ["confirm", "reject"],
+    },
+    deleteMode: {
+      type: String,
+      enum: ["single", "future", "all"],
+    },
+    occurrenceDate: { type: String },
+    conflictingEvents: { type: [ConflictingEventSchema] },
   },
   { _id: false },
 );
@@ -77,12 +97,9 @@ const ChatMessageSchema = new Schema<
       type: String,
       required: true,
     },
-    proposedChange: {
+    proposedChanges: {
-      type: ProposedChangeSchema,
+      type: [ProposedChangeSchema],
-    },
+      default: undefined,
-    respondedAction: {
-      type: String,
-      enum: ["confirm", "reject"],
     },
   },
   {

apps/server/src/repositories/mongo/models/EventModel.ts

@@ -1,5 +1,5 @@
 import mongoose, { Schema, Document, Model } from "mongoose";
-import { CalendarEvent } from "@caldav/shared";
+import { CalendarEvent } from "@calchat/shared";
 import { IdVirtual } from "./types";
 
 export interface EventDocument extends Omit<CalendarEvent, "id">, Document {
@@ -19,6 +19,12 @@ const EventSchema = new Schema<
       required: true,
       index: true,
     },
+    caldavUUID: {
+      type: String,
+    },
+    etag: {
+      type: String,
+    },
     title: {
       type: String,
       required: true,
@@ -39,13 +45,13 @@ const EventSchema = new Schema<
     note: {
       type: String,
     },
-    isRecurring: {
-      type: Boolean,
-      default: false,
-    },
     recurrenceRule: {
       type: String,
     },
+    exceptionDates: {
+      type: [String],
+      default: [],
+    },
   },
   {
     timestamps: true,

apps/server/src/repositories/mongo/models/UserModel.ts

@@ -1,5 +1,5 @@
 import mongoose, { Schema, Document, Model } from "mongoose";
-import { User } from "@caldav/shared";
+import { User } from "@calchat/shared";
 import { IdVirtual } from "./types";
 
 export interface UserDocument extends Omit<User, "id">, Document {
@@ -21,7 +21,7 @@ const UserSchema = new Schema<
       lowercase: true,
       trim: true,
     },
-    displayName: {
+    userName: {
       type: String,
       required: true,
       trim: true,

apps/server/src/routes/auth.routes.ts

@@ -6,8 +6,6 @@ export function createAuthRoutes(authController: AuthController): Router {
 
   router.post("/login", (req, res) => authController.login(req, res));
   router.post("/register", (req, res) => authController.register(req, res));
-  router.post("/refresh", (req, res) => authController.refresh(req, res));
-  router.post("/logout", (req, res) => authController.logout(req, res));
 
   return router;
 }

apps/server/src/routes/caldav.routes.ts

@@ -0,0 +1,22 @@
+import { Router } from "express";
+import { authenticate } from "../controllers";
+import { CaldavController } from "../controllers/CaldavController";
+
+export function createCaldavRoutes(caldavController: CaldavController): Router {
+  const router = Router();
+
+  router.use(authenticate);
+
+  router.put("/config", (req, res) => caldavController.saveConfig(req, res));
+  router.get("/config", (req, res) => caldavController.loadConfig(req, res));
+  router.delete("/config", (req, res) =>
+    caldavController.deleteConfig(req, res),
+  );
+  router.post("/pull", (req, res) => caldavController.pullEvents(req, res));
+  router.post("/pushAll", (req, res) => caldavController.pushEvents(req, res));
+  router.post("/push/:caldavUUID", (req, res) =>
+    caldavController.pushEvent(req, res),
+  );
+
+  return router;
+}

apps/server/src/routes/chat.routes.ts

@@ -1,6 +1,5 @@
 import { Router } from "express";
-import { ChatController } from "../controllers";
+import { ChatController, authenticate } from "../controllers";
-import { authenticate } from "../middleware";
 
 export function createChatRoutes(chatController: ChatController): Router {
   const router = Router();
@@ -20,6 +19,9 @@ export function createChatRoutes(chatController: ChatController): Router {
   router.get("/conversations/:id", (req, res) =>
     chatController.getConversation(req, res),
   );
+  router.put("/messages/:messageId/proposal", (req, res) =>
+    chatController.updateProposalEvent(req, res),
+  );
 
   return router;
 }

apps/server/src/routes/event.routes.ts

@@ -1,6 +1,5 @@
 import { Router } from "express";
-import { EventController } from "../controllers";
+import { EventController, authenticate } from "../controllers";
-import { authenticate } from "../middleware";
 
 export function createEventRoutes(eventController: EventController): Router {
   const router = Router();

apps/server/src/routes/index.ts

@@ -6,12 +6,15 @@ import {
   AuthController,
   ChatController,
   EventController,
+  CaldavController,
 } from "../controllers";
+import { createCaldavRoutes } from "./caldav.routes";
 
 export interface Controllers {
   authController: AuthController;
   chatController: ChatController;
   eventController: EventController;
+  caldavController: CaldavController;
 }
 
 export function createRoutes(controllers: Controllers): Router {
@@ -20,6 +23,7 @@ export function createRoutes(controllers: Controllers): Router {
   router.use("/auth", createAuthRoutes(controllers.authController));
   router.use("/chat", createChatRoutes(controllers.chatController));
   router.use("/events", createEventRoutes(controllers.eventController));
+  router.use("/caldav", createCaldavRoutes(controllers.caldavController));
 
   return router;
 }

apps/server/src/services/AuthService.ts

@@ -1,13 +1,17 @@
-import { User, CreateUserDTO, LoginDTO, AuthResponse } from "@caldav/shared";
+import { CreateUserDTO, LoginDTO, AuthResponse } from "@calchat/shared";
 import { UserRepository } from "./interfaces";
-import * as jwt from "../utils/jwt";
 import * as password from "../utils/password";
 
 export class AuthService {
   constructor(private userRepo: UserRepository) {}
 
   async login(data: LoginDTO): Promise<AuthResponse> {
-    const user = await this.userRepo.findByEmail(data.email);
+    // Try email first, then userName
+    let user = await this.userRepo.findByEmail(data.identifier);
+    if (!user) {
+      user = await this.userRepo.findByUserName(data.identifier);
+    }
+
     if (!user || !user.passwordHash) {
       throw new Error("Invalid credentials");
     }
@@ -21,26 +25,23 @@ export class AuthService {
   }
 
   async register(data: CreateUserDTO): Promise<AuthResponse> {
-    const existingUser = await this.userRepo.findByEmail(data.email);
+    const existingEmail = await this.userRepo.findByEmail(data.email);
-    if (existingUser) {
+    if (existingEmail) {
       throw new Error("Email already exists");
     }
 
+    const existingUserName = await this.userRepo.findByUserName(data.userName);
+    if (existingUserName) {
+      throw new Error("Username already exists");
+    }
+
     const passwordHash = await password.hash(data.password);
     const user = await this.userRepo.create({
       email: data.email,
-      displayName: data.displayName,
+      userName: data.userName,
       passwordHash,
     });
 
     return { user, accessToken: "" };
   }
-
-  async refreshToken(refreshToken: string): Promise<AuthResponse> {
-    throw new Error("Not implemented");
-  }
-
-  async logout(userId: string): Promise<void> {
-    throw new Error("Not implemented");
-  }
 }

apps/server/src/services/CaldavService.ts

@@ -0,0 +1,271 @@
+import crypto from "crypto";
+import { DAVClient } from "tsdav";
+import ICAL from "ical.js";
+import { createLogger } from "../logging/logger";
+import { CaldavRepository } from "./interfaces/CaldavRepository";
+import {
+  CalendarEvent,
+  CreateEventDTO,
+  CaldavConfig,
+  formatDateKey,
+} from "@calchat/shared";
+import { EventService } from "./EventService";
+
+const logger = createLogger("CaldavService");
+
+export class CaldavService {
+  constructor(
+    private caldavRepo: CaldavRepository,
+    private eventService: EventService,
+  ) {}
+
+  /**
+   * Login to CalDAV server and return client + first calendar.
+   */
+  async connect(userId: string) {
+    const config = await this.caldavRepo.findByUserId(userId);
+    if (config === null) {
+      throw new Error(`Coudn't find config by user id ${userId}`);
+    }
+    const client = new DAVClient({
+      serverUrl: config.serverUrl,
+      credentials: {
+        username: config.username,
+        password: config.password,
+      },
+      authMethod: "Basic",
+      defaultAccountType: "caldav",
+    });
+
+    try {
+      await client.login();
+    } catch (error) {
+      throw new Error("Caldav login failed");
+    }
+
+    const calendars = await client.fetchCalendars();
+    if (calendars.length === 0) {
+      throw new Error("No calendars found on CalDAV server");
+    }
+
+    return { client, calendar: calendars[0] };
+  }
+
+  /**
+   * Pull events from CalDAV server and sync with local database.
+   * - Compares etags to skip unchanged events
+   * - Creates new or updates existing events in the database
+   * - Deletes local events that were removed on the CalDAV server
+   *
+   * @returns List of newly created or updated events
+   */
+  async pullEvents(userId: string): Promise<CalendarEvent[]> {
+    const { client, calendar } = await this.connect(userId);
+    const calendarEvents: CalendarEvent[] = [];
+    const caldavEventUUIDs = new Set<string>();
+
+    const events = await client.fetchCalendarObjects({ calendar });
+    for (const event of events) {
+      const etag = event.etag;
+      const jcal = ICAL.parse(event.data);
+      const comp = new ICAL.Component(jcal);
+      // A CalendarObject (.ics file) can contain multiple VEVENTs (e.g.
+      // recurring events with RECURRENCE-ID exceptions), but the etag belongs
+      // to the whole file, not individual VEVENTs. We only need the first
+      // VEVENT since we handle recurrence via RRULE/exceptionDates, not as
+      // separate events.
+      const vevent = comp.getFirstSubcomponent("vevent");
+      if (!vevent) continue;
+
+      const icalEvent = new ICAL.Event(vevent);
+      caldavEventUUIDs.add(icalEvent.uid);
+
+      const exceptionDates = vevent
+        .getAllProperties("exdate")
+        .flatMap((prop) => prop.getValues())
+        .map((time: ICAL.Time) => formatDateKey(time.toJSDate()));
+
+      const existingEvent = await this.eventService.findByCaldavUUID(
+        userId,
+        icalEvent.uid,
+      );
+
+      const didChange = existingEvent?.etag !== etag;
+
+      if (existingEvent && !didChange) {
+        continue;
+      }
+
+      const eventObject: CreateEventDTO = {
+        caldavUUID: icalEvent.uid,
+        etag,
+        title: icalEvent.summary,
+        description: icalEvent.description,
+        startTime: icalEvent.startDate.toJSDate(),
+        endTime: icalEvent.endDate.toJSDate(),
+        recurrenceRule: vevent.getFirstPropertyValue("rrule")?.toString(),
+        exceptionDates,
+        caldavSyncStatus: "synced",
+      };
+
+      const calendarEvent = existingEvent
+        ? await this.eventService.update(existingEvent.id, userId, eventObject)
+        : await this.eventService.create(userId, eventObject);
+
+      if (calendarEvent) {
+        calendarEvents.push(calendarEvent);
+      }
+    }
+
+    // delete all events, that got deleted remotely
+    const localEvents = await this.eventService.getAll(userId);
+    for (const localEvent of localEvents) {
+      if (
+        localEvent.caldavUUID &&
+        !caldavEventUUIDs.has(localEvent.caldavUUID)
+      ) {
+        await this.eventService.delete(localEvent.id, userId);
+      }
+    }
+
+    return calendarEvents;
+  }
+
+  /**
+   * Push a single event to the CalDAV server.
+   * Creates a new event if no caldavUUID exists, updates otherwise.
+   */
+  async pushEvent(userId: string, event: CalendarEvent): Promise<void> {
+    const { client, calendar } = await this.connect(userId);
+
+    try {
+      if (event.caldavUUID) {
+        await client.updateCalendarObject({
+          calendarObject: {
+            url: `${calendar.url}${event.caldavUUID}.ics`,
+            data: this.toICalString(event.caldavUUID, event),
+            etag: event.etag || "",
+          },
+        });
+      } else {
+        const uid = crypto.randomUUID();
+        await client.createCalendarObject({
+          calendar,
+          filename: `${uid}.ics`,
+          iCalString: this.toICalString(uid, event),
+        });
+        await this.eventService.update(event.id, userId, { caldavUUID: uid });
+      }
+
+      // Fetch updated etag from server
+      const objects = await client.fetchCalendarObjects({ calendar });
+      const caldavUUID =
+        event.caldavUUID ||
+        (await this.eventService.getById(event.id, userId))?.caldavUUID;
+      const pushed = objects.find((o) => o.data?.includes(caldavUUID!));
+
+      await this.eventService.update(event.id, userId, {
+        etag: pushed?.etag || undefined,
+        caldavSyncStatus: "synced",
+      });
+    } catch (error) {
+      await this.eventService.update(event.id, userId, {
+        caldavSyncStatus: "error",
+      });
+      throw error;
+    }
+  }
+
+  /**
+   * Build an iCalendar string from a CalendarEvent using ical.js.
+   */
+  private toICalString(uid: string, event: CalendarEvent): string {
+    const vcalendar = new ICAL.Component("vcalendar");
+    vcalendar.addPropertyWithValue("version", "2.0");
+    vcalendar.addPropertyWithValue("prodid", "-//CalChat//EN");
+
+    const vevent = new ICAL.Component("vevent");
+    vevent.addPropertyWithValue("uid", uid);
+    vevent.addPropertyWithValue("summary", event.title);
+    vevent.addPropertyWithValue(
+      "dtstart",
+      ICAL.Time.fromJSDate(new Date(event.startTime)),
+    );
+    vevent.addPropertyWithValue(
+      "dtend",
+      ICAL.Time.fromJSDate(new Date(event.endTime)),
+    );
+
+    if (event.description) {
+      vevent.addPropertyWithValue("description", event.description);
+    }
+
+    if (event.recurrenceRule) {
+      // Strip RRULE: prefix if present — fromString expects only the value part,
+      // and addPropertyWithValue("rrule", ...) adds the RRULE: prefix automatically.
+      const rule = event.recurrenceRule.replace(/^RRULE:/i, "");
+      vevent.addPropertyWithValue("rrule", ICAL.Recur.fromString(rule));
+    }
+
+    if (event.exceptionDates?.length) {
+      for (const exdate of event.exceptionDates) {
+        vevent.addPropertyWithValue("exdate", ICAL.Time.fromDateString(exdate));
+      }
+    }
+
+    vcalendar.addSubcomponent(vevent);
+    return vcalendar.toString();
+  }
+
+  async pushAll(userId: string): Promise<void> {
+    const allEvents = await this.eventService.getAll(userId);
+    for (const event of allEvents) {
+      if (event.caldavSyncStatus !== "synced") {
+        await this.pushEvent(userId, event);
+      }
+    }
+  }
+
+  async deleteEvent(userId: string, caldavUUID: string) {
+    const { client, calendar } = await this.connect(userId);
+
+    await client.deleteCalendarObject({
+      calendarObject: {
+        url: `${calendar.url}${caldavUUID}.ics`,
+      },
+    });
+  }
+
+  async findEventByCaldavUUID(userId: string, caldavUUID: string) {
+    return this.eventService.findByCaldavUUID(userId, caldavUUID);
+  }
+
+  async getConfig(userId: string): Promise<CaldavConfig | null> {
+    return this.caldavRepo.findByUserId(userId);
+  }
+
+  async saveConfig(config: CaldavConfig): Promise<CaldavConfig> {
+    const savedConfig = await this.caldavRepo.createOrUpdate(config);
+    try {
+      await this.connect(savedConfig.userId);
+    } catch (error) {
+      await this.caldavRepo.deleteByUserId(savedConfig.userId);
+      throw new Error("failed to connect");
+    }
+    return savedConfig;
+  }
+
+  async deleteConfig(userId: string) {
+    return await this.caldavRepo.deleteByUserId(userId);
+  }
+
+  /**
+   * Sync with CalDAV server if config exists. Silent no-op if no config.
+   */
+  async sync(userId: string): Promise<void> {
+    const config = await this.getConfig(userId);
+    if (!config) return;
+    await this.pushAll(userId);
+    await this.pullEvents(userId);
+  }
+}

apps/server/src/services/ChatService.ts

@@ -9,12 +9,17 @@ import {
   CreateEventDTO,
   UpdateEventDTO,
   EventAction,
-  CreateMessageDTO,
+  RecurringDeleteMode,
-} from "@caldav/shared";
+  ConflictingEvent,
-import { ChatRepository, EventRepository, AIProvider } from "./interfaces";
+} from "@calchat/shared";
+import { ChatRepository, AIProvider } from "./interfaces";
+import { EventService } from "./EventService";
 import { getWeeksOverview, getMonthOverview } from "../utils/eventFormatters";
 
-type TestResponse = { content: string; proposedChange?: ProposedEventChange };
+type TestResponse = {
+  content: string;
+  proposedChanges?: ProposedEventChange[];
+};
 
 // Test response index (cycles through responses)
 let responseIndex = 0;
@@ -22,7 +27,154 @@ let responseIndex = 0;
 // Static test responses (event proposals)
 const staticResponses: TestResponse[] = [
   // {{{
-  // Response 0: Help response (text only)
+  // === SPORT TEST SCENARIO (3 steps) ===
+  // Response 0: Wiederkehrendes Event - jeden Mittwoch Sport
+  {
+    content:
+      "Super! Ich erstelle dir einen wiederkehrenden Termin für Sport jeden Mittwoch:",
+    proposedChanges: [
+      {
+        id: "sport-create",
+        action: "create",
+        event: {
+          title: "Sport",
+          startTime: getDay("Wednesday", 1, 18, 0),
+          endTime: getDay("Wednesday", 1, 19, 30),
+          description: "Wöchentliches Training",
+          recurrenceRule: "FREQ=WEEKLY;BYDAY=WE",
+        },
+      },
+    ],
+  },
+  // Response 1: Ausnahme hinzufügen (2 Wochen später) - DYNAMIC placeholder
+  { content: "" },
+  // Response 2: UNTIL hinzufügen (nach 6 Wochen) - DYNAMIC placeholder
+  { content: "" },
+  // Response 3: Weitere Ausnahme in 2 Wochen - DYNAMIC placeholder
+  { content: "" },
+  // === MULTI-EVENT TEST RESPONSES ===
+  // Response 3: 3 Meetings an verschiedenen Tagen
+  {
+    content: "Alles klar! Ich erstelle dir 3 Team-Meetings für diese Woche:",
+    proposedChanges: [
+      {
+        id: "multi-1-a",
+        action: "create",
+        event: {
+          title: "Team-Meeting Montag",
+          startTime: getDay("Monday", 1, 10, 0),
+          endTime: getDay("Monday", 1, 11, 0),
+          description: "Wöchentliches Standup",
+        },
+      },
+      {
+        id: "multi-1-b",
+        action: "create",
+        event: {
+          title: "Team-Meeting Mittwoch",
+          startTime: getDay("Wednesday", 1, 10, 0),
+          endTime: getDay("Wednesday", 1, 11, 0),
+          description: "Sprint Planning",
+        },
+      },
+      {
+        id: "multi-1-c",
+        action: "create",
+        event: {
+          title: "Team-Meeting Freitag",
+          startTime: getDay("Friday", 1, 10, 0),
+          endTime: getDay("Friday", 1, 11, 0),
+          description: "Retrospektive",
+        },
+      },
+    ],
+  },
+  // Response 1: 5 Termine für einen Projekttag
+  {
+    content: "Ich habe deinen kompletten Projekttag am Dienstag geplant:",
+    proposedChanges: [
+      {
+        id: "multi-2-a",
+        action: "create",
+        event: {
+          title: "Kickoff-Meeting",
+          startTime: getDay("Tuesday", 1, 9, 0),
+          endTime: getDay("Tuesday", 1, 10, 0),
+          description: "Projektstart mit dem Team",
+        },
+      },
+      {
+        id: "multi-2-b",
+        action: "create",
+        event: {
+          title: "Design Review",
+          startTime: getDay("Tuesday", 1, 10, 30),
+          endTime: getDay("Tuesday", 1, 11, 30),
+          description: "UI/UX Besprechung",
+        },
+      },
+      {
+        id: "multi-2-c",
+        action: "create",
+        event: {
+          title: "Mittagspause",
+          startTime: getDay("Tuesday", 1, 12, 0),
+          endTime: getDay("Tuesday", 1, 13, 0),
+          description: "Team-Lunch",
+        },
+      },
+      {
+        id: "multi-2-d",
+        action: "create",
+        event: {
+          title: "Tech Review",
+          startTime: getDay("Tuesday", 1, 14, 0),
+          endTime: getDay("Tuesday", 1, 15, 30),
+          description: "Architektur-Diskussion",
+        },
+      },
+      {
+        id: "multi-2-e",
+        action: "create",
+        event: {
+          title: "Wrap-up",
+          startTime: getDay("Tuesday", 1, 16, 0),
+          endTime: getDay("Tuesday", 1, 16, 30),
+          description: "Zusammenfassung und nächste Schritte",
+        },
+      },
+    ],
+  },
+  // Response 2: 2 wiederkehrende Termine
+  {
+    content: "Ich erstelle dir zwei wiederkehrende Fitness-Termine:",
+    proposedChanges: [
+      {
+        id: "multi-3-a",
+        action: "create",
+        event: {
+          title: "Yoga",
+          startTime: getDay("Monday", 1, 7, 0),
+          endTime: getDay("Monday", 1, 8, 0),
+          description: "Morgen-Yoga",
+          recurrenceRule: "FREQ=WEEKLY;BYDAY=MO,WE,FR",
+        },
+      },
+      {
+        id: "multi-3-b",
+        action: "create",
+        event: {
+          title: "Laufen",
+          startTime: getDay("Tuesday", 1, 18, 0),
+          endTime: getDay("Tuesday", 1, 19, 0),
+          description: "Abendlauf im Park",
+          recurrenceRule: "FREQ=WEEKLY;BYDAY=TU,TH",
+        },
+      },
+    ],
+  },
+  // === ORIGINAL RESPONSES ===
+  // Response 3: Help response (text only)
   {
     content:
       "Ich bin dein Kalender-Assistent! Du kannst mir einfach sagen, welche Termine du erstellen, ändern oder löschen möchtest. Zum Beispiel:\n\n" +
@@ -35,30 +187,35 @@ const staticResponses: TestResponse[] = [
   {
     content:
       "Alles klar! Ich erstelle dir einen Termin für das Meeting mit Jens am nächsten Freitag um 14:00 Uhr:",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-1",
-        title: "Meeting mit Jens",
+        action: "create",
-        startTime: getDay("Friday", 1, 14, 0),
+        event: {
-        endTime: getDay("Friday", 1, 15, 0),
+          title: "Meeting mit Jens",
-        description: "Arbeitstreffen",
+          startTime: getDay("Friday", 1, 14, 0),
+          endTime: getDay("Friday", 1, 15, 0),
+          description: "Arbeitstreffen",
+        },
       },
-    },
+    ],
   },
   // Response 2: Recurring event - every Saturday 10:00
   {
     content:
       "Verstanden! Ich erstelle einen wiederkehrenden Termin: Jeden Samstag um 10:00 Uhr Badezimmer putzen:",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-2",
-        title: "Badezimmer putzen",
+        action: "create",
-        startTime: getDay("Saturday", 1, 10, 0),
+        event: {
-        endTime: getDay("Saturday", 1, 11, 0),
+          title: "Badezimmer putzen",
-        isRecurring: true,
+          startTime: getDay("Saturday", 1, 10, 0),
-        recurrenceRule: "FREQ=WEEKLY;BYDAY=SA",
+          endTime: getDay("Saturday", 1, 11, 0),
+          recurrenceRule: "FREQ=WEEKLY;BYDAY=SA",
+        },
       },
-    },
+    ],
   },
   // Response 3: 2-week overview (DYNAMIC - placeholder)
   { content: "" },
@@ -68,45 +225,53 @@ const staticResponses: TestResponse[] = [
   {
     content:
       "Ich habe dir einen Arzttermin eingetragen. Denk daran, deine Versichertenkarte mitzunehmen!",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-5",
-        title: "Arzttermin Dr. Müller",
+        action: "create",
-        startTime: getDay("Wednesday", 1, 9, 30),
+        event: {
-        endTime: getDay("Wednesday", 1, 10, 30),
+          title: "Arzttermin Dr. Müller",
-        description: "Routineuntersuchung - Versichertenkarte nicht vergessen",
+          startTime: getDay("Wednesday", 1, 9, 30),
+          endTime: getDay("Wednesday", 1, 10, 30),
+          description:
+            "Routineuntersuchung - Versichertenkarte nicht vergessen",
+        },
       },
-    },
+    ],
   },
   // Response 6: Birthday - yearly recurring
   {
     content:
       "Geburtstage vergisst man leicht - aber nicht mit mir! Ich habe Mamas Geburtstag eingetragen:",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-6",
-        title: "Mamas Geburtstag",
+        action: "create",
-        startTime: getDay("Thursday", 2, 0, 0),
+        event: {
-        endTime: getDay("Thursday", 2, 23, 59),
+          title: "Mamas Geburtstag",
-        isRecurring: true,
+          startTime: getDay("Thursday", 2, 0, 0),
-        recurrenceRule: "FREQ=YEARLY",
+          endTime: getDay("Thursday", 2, 23, 59),
+          recurrenceRule: "FREQ=YEARLY",
+        },
       },
-    },
+    ],
   },
   // Response 7: Gym - recurring for 2 months (8 weeks)
   {
     content:
       "Perfekt! Ich habe dein Probetraining eingetragen - jeden Dienstag für die nächsten 2 Monate:",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-7",
-        title: "Fitnessstudio Probetraining",
+        action: "create",
-        startTime: getDay("Tuesday", 1, 18, 0),
+        event: {
-        endTime: getDay("Tuesday", 1, 19, 30),
+          title: "Fitnessstudio Probetraining",
-        isRecurring: true,
+          startTime: getDay("Tuesday", 1, 18, 0),
-        recurrenceRule: "FREQ=WEEKLY;BYDAY=TU;COUNT=8",
+          endTime: getDay("Tuesday", 1, 19, 30),
+          recurrenceRule: "FREQ=WEEKLY;BYDAY=TU;COUNT=8",
+        },
       },
-    },
+    ],
   },
   // Response 8: 1-week overview (DYNAMIC - placeholder)
   { content: "" },
@@ -114,44 +279,52 @@ const staticResponses: TestResponse[] = [
   {
     content:
       "Alles klar! Ich habe das Telefonat mit deiner Mutter eingetragen:",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-9",
-        title: "Telefonat mit Mama",
+        action: "create",
-        startTime: getDay("Wednesday", 1, 11, 0),
+        event: {
-        endTime: getDay("Wednesday", 1, 11, 30),
+          title: "Telefonat mit Mama",
+          startTime: getDay("Wednesday", 1, 11, 0),
+          endTime: getDay("Wednesday", 1, 11, 30),
+        },
       },
-    },
+    ],
   },
   // Response 10: Update "Telefonat mit Mama" +3 days (DYNAMIC - placeholder)
   { content: "" },
   // Response 11: Birthday party - evening event
   {
     content: "Super! Die Geburtstagsfeier ist eingetragen. Viel Spaß!",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-11",
-        title: "Geburtstagsfeier Lisa",
+        action: "create",
-        startTime: getDay("Saturday", 2, 19, 0),
+        event: {
-        endTime: getDay("Saturday", 2, 23, 0),
+          title: "Geburtstagsfeier Lisa",
-        description: "Geschenk: Buch über Fotografie",
+          startTime: getDay("Saturday", 2, 19, 0),
+          endTime: getDay("Saturday", 2, 23, 0),
+          description: "Geschenk: Buch über Fotografie",
+        },
       },
-    },
+    ],
   },
   // Response 12: Language course - limited to 8 weeks (Thu + Sat)
   {
     content:
       "Dein Spanischkurs ist eingetragen! Er läuft jeden Donnerstag und Samstag für die nächsten 8 Wochen:",
-    proposedChange: {
+    proposedChanges: [
-      action: "create",
+      {
-      event: {
+        id: "test-12",
-        title: "Spanischkurs VHS",
+        action: "create",
-        startTime: getDay("Thursday", 1, 19, 0),
+        event: {
-        endTime: getDay("Thursday", 1, 20, 30),
+          title: "Spanischkurs VHS",
-        isRecurring: true,
+          startTime: getDay("Thursday", 1, 19, 0),
-        recurrenceRule: "FREQ=WEEKLY;BYDAY=TH,SA;COUNT=8",
+          endTime: getDay("Thursday", 1, 20, 30),
+          recurrenceRule: "FREQ=WEEKLY;BYDAY=TH,SA;COUNT=8",
+        },
       },
-    },
+    ],
   },
   // Response 13: Monthly overview (DYNAMIC - placeholder)
   { content: "" },
@@ -160,46 +333,165 @@ const staticResponses: TestResponse[] = [
 
 async function getTestResponse(
   index: number,
-  eventRepo: EventRepository,
+  eventService: EventService,
   userId: string,
 ): Promise<TestResponse> {
   const responseIdx = index % staticResponses.length;
 
-  // Dynamic responses: fetch events from DB and format
+  // === SPORT TEST SCENARIO (Dynamic responses) ===
-  if (responseIdx === 3) {
+  // Response 1: Add exception to "Sport" (2 weeks later)
-    return { content: await getWeeksOverview(eventRepo, userId, 2) };
+  if (responseIdx === 1) {
+    const events = await eventService.getAll(userId);
+    const sportEvent = events.find((e) => e.title === "Sport");
+    if (sportEvent) {
+      // Calculate date 2 weeks from the first occurrence
+      const exceptionDate = new Date(sportEvent.startTime);
+      exceptionDate.setDate(exceptionDate.getDate() + 14);
+      const exceptionDateStr = exceptionDate.toISOString().split("T")[0];
+
+      return {
+        content:
+          "Verstanden! Ich füge eine Ausnahme für den Sport-Termin in 2 Wochen hinzu:",
+        proposedChanges: [
+          {
+            id: "sport-exception",
+            action: "delete",
+            eventId: sportEvent.id,
+            deleteMode: "single",
+            occurrenceDate: exceptionDateStr,
+            event: {
+              title: sportEvent.title,
+              startTime: exceptionDate,
+              endTime: new Date(exceptionDate.getTime() + 90 * 60 * 1000), // +90 min
+              description: sportEvent.description,
+              recurrenceRule: sportEvent.recurrenceRule,
+              exceptionDates: sportEvent.exceptionDates,
+            },
+          },
+        ],
+      };
+    }
+    return {
+      content:
+        "Ich konnte keinen Termin 'Sport' finden. Bitte erstelle ihn zuerst.",
+    };
   }
 
-  if (responseIdx === 4) {
+  // Response 2: Add UNTIL to "Sport" (after 6 weeks total)
+  if (responseIdx === 2) {
+    const events = await eventService.getAll(userId);
+    const sportEvent = events.find((e) => e.title === "Sport");
+    if (sportEvent) {
+      // Calculate UNTIL date: 6 weeks from start
+      const untilDate = new Date(sportEvent.startTime);
+      untilDate.setDate(untilDate.getDate() + 42); // 6 weeks
+      const untilStr =
+        untilDate.toISOString().replace(/[-:]/g, "").split(".")[0] + "Z";
+
+      const newRule = `FREQ=WEEKLY;BYDAY=WE;UNTIL=${untilStr}`;
+
+      return {
+        content: "Alles klar! Ich beende die Sport-Serie nach 6 Wochen:",
+        proposedChanges: [
+          {
+            id: "sport-until",
+            action: "update",
+            eventId: sportEvent.id,
+            updates: { recurrenceRule: newRule },
+            event: {
+              title: sportEvent.title,
+              startTime: sportEvent.startTime,
+              endTime: sportEvent.endTime,
+              description: sportEvent.description,
+              recurrenceRule: newRule,
+              exceptionDates: sportEvent.exceptionDates,
+            },
+          },
+        ],
+      };
+    }
+    return {
+      content:
+        "Ich konnte keinen Termin 'Sport' finden. Bitte erstelle ihn zuerst.",
+    };
+  }
+
+  // Response 3: Add another exception to "Sport" (2 weeks after the first exception)
+  if (responseIdx === 3) {
+    const events = await eventService.getAll(userId);
+    const sportEvent = events.find((e) => e.title === "Sport");
+    if (sportEvent) {
+      // Calculate date 4 weeks from the first occurrence (2 weeks after the first exception)
+      const exceptionDate = new Date(sportEvent.startTime);
+      exceptionDate.setDate(exceptionDate.getDate() + 28); // 4 weeks
+      const exceptionDateStr = exceptionDate.toISOString().split("T")[0];
+
+      return {
+        content:
+          "Alles klar! Ich füge eine weitere Ausnahme für den Sport-Termin hinzu:",
+        proposedChanges: [
+          {
+            id: "sport-exception-2",
+            action: "delete",
+            eventId: sportEvent.id,
+            deleteMode: "single",
+            occurrenceDate: exceptionDateStr,
+            event: {
+              title: sportEvent.title,
+              startTime: exceptionDate,
+              endTime: new Date(exceptionDate.getTime() + 90 * 60 * 1000), // +90 min
+              description: sportEvent.description,
+              recurrenceRule: sportEvent.recurrenceRule,
+              exceptionDates: sportEvent.exceptionDates,
+            },
+          },
+        ],
+      };
+    }
+    return {
+      content:
+        "Ich konnte keinen Termin 'Sport' finden. Bitte erstelle ihn zuerst.",
+    };
+  }
+
+  // Dynamic responses: fetch events from DB and format
+  // (Note: indices shifted by +3 due to new sport responses)
+  if (responseIdx === 6) {
+    return { content: await getWeeksOverview(eventService, userId, 2) };
+  }
+
+  if (responseIdx === 7) {
     // Delete "Meeting mit Jens"
-    const events = await eventRepo.findByUserId(userId);
+    const events = await eventService.getAll(userId);
     const jensEvent = events.find((e) => e.title === "Meeting mit Jens");
     if (jensEvent) {
       return {
         content: "Soll ich diesen Termin wirklich löschen?",
-        proposedChange: {
+        proposedChanges: [
-          action: "delete",
+          {
-          eventId: jensEvent.id,
+            id: "test-4",
-          event: {
+            action: "delete",
-            title: jensEvent.title,
+            eventId: jensEvent.id,
-            startTime: jensEvent.startTime,
+            event: {
-            endTime: jensEvent.endTime,
+              title: jensEvent.title,
-            description: jensEvent.description,
+              startTime: jensEvent.startTime,
-            isRecurring: jensEvent.isRecurring,
+              endTime: jensEvent.endTime,
+              description: jensEvent.description,
+            },
           },
-        },
+        ],
       };
     }
     return { content: "Ich konnte keinen Termin 'Meeting mit Jens' finden." };
   }
 
-  if (responseIdx === 8) {
+  if (responseIdx === 11) {
-    return { content: await getWeeksOverview(eventRepo, userId, 1) };
+    return { content: await getWeeksOverview(eventService, userId, 1) };
   }
 
-  if (responseIdx === 10) {
+  if (responseIdx === 13) {
     // Update "Telefonat mit Mama" +3 days and change time to 13:00
-    const events = await eventRepo.findByUserId(userId);
+    const events = await eventService.getAll(userId);
     const mamaEvent = events.find((e) => e.title === "Telefonat mit Mama");
     if (mamaEvent) {
       const newStart = new Date(mamaEvent.startTime);
@@ -210,28 +502,31 @@ async function getTestResponse(
       return {
         content:
           "Alles klar, ich verschiebe das Telefonat mit Mama auf Samstag um 13:00 Uhr:",
-        proposedChange: {
+        proposedChanges: [
-          action: "update",
+          {
-          eventId: mamaEvent.id,
+            id: "test-10",
-          updates: { startTime: newStart, endTime: newEnd },
+            action: "update",
-          // Include event with new times for display
+            eventId: mamaEvent.id,
-          event: {
+            updates: { startTime: newStart, endTime: newEnd },
-            title: mamaEvent.title,
+            // Include event with new times for display
-            startTime: newStart,
+            event: {
-            endTime: newEnd,
+              title: mamaEvent.title,
-            description: mamaEvent.description,
+              startTime: newStart,
+              endTime: newEnd,
+              description: mamaEvent.description,
+            },
           },
-        },
+        ],
       };
     }
     return { content: "Ich konnte keinen Termin 'Telefonat mit Mama' finden." };
   }
 
-  if (responseIdx === 13) {
+  if (responseIdx === 16) {
     const now = new Date();
     return {
       content: await getMonthOverview(
-        eventRepo,
+        eventService,
         userId,
         now.getFullYear(),
         now.getMonth(),
@@ -245,7 +540,7 @@ async function getTestResponse(
 export class ChatService {
   constructor(
     private chatRepo: ChatRepository,
-    private eventRepo: EventRepository,
+    private eventService: EventService,
     private aiProvider: AIProvider,
   ) {}
 
@@ -269,11 +564,14 @@ export class ChatService {
 
     if (process.env.USE_TEST_RESPONSES === "true") {
       // Test mode: use static responses
-      response = await getTestResponse(responseIndex, this.eventRepo, userId);
+      response = await getTestResponse(
+        responseIndex,
+        this.eventService,
+        userId,
+      );
       responseIndex++;
     } else {
       // Production mode: use real AI
-      const events = await this.eventRepo.findByUserId(userId);
       const history = await this.chatRepo.getMessages(conversationId, {
         limit: 20,
       });
@@ -281,8 +579,16 @@ export class ChatService {
       response = await this.aiProvider.processMessage(data.content, {
         userId,
         conversationHistory: history,
-        existingEvents: events,
         currentDate: new Date(),
+        fetchEventsInRange: async (start, end) => {
+          return this.eventService.getByDateRange(userId, start, end);
+        },
+        searchEvents: async (query) => {
+          return this.eventService.searchByTitle(userId, query);
+        },
+        fetchEventById: async (eventId) => {
+          return this.eventService.getById(eventId, userId);
+        },
       });
     }
 
@@ -290,7 +596,7 @@ export class ChatService {
     const answerMessage = await this.chatRepo.createMessage(conversationId, {
       sender: "assistant",
       content: response.content,
-      proposedChange: response.proposedChange,
+      proposedChanges: response.proposedChanges,
     });
 
     return { message: answerMessage, conversationId: conversationId };
@@ -300,32 +606,56 @@ export class ChatService {
     userId: string,
     conversationId: string,
     messageId: string,
+    proposalId: string,
     action: EventAction,
     event?: CreateEventDTO,
     eventId?: string,
     updates?: UpdateEventDTO,
+    deleteMode?: RecurringDeleteMode,
+    occurrenceDate?: string,
   ): Promise<ChatResponse> {
-    // Update original message with respondedAction
+    // Update specific proposal with respondedAction
-    await this.chatRepo.updateMessage(messageId, {
+    await this.chatRepo.updateProposalResponse(
-      respondedAction: "confirm",
+      messageId,
-    });
+      proposalId,
+      "confirm",
+    );
 
     // Perform the actual event operation
     let content: string;
 
     if (action === "create" && event) {
-      const createdEvent = await this.eventRepo.create(userId, event);
+      const createdEvent = await this.eventService.create(userId, event);
       content = `Der Termin "${createdEvent.title}" wurde erstellt.`;
     } else if (action === "update" && eventId && updates) {
-      const updatedEvent = await this.eventRepo.update(eventId, updates);
+      const updatedEvent = await this.eventService.update(
+        eventId,
+        userId,
+        updates,
+      );
       content = updatedEvent
         ? `Der Termin "${updatedEvent.title}" wurde aktualisiert.`
         : "Termin nicht gefunden.";
     } else if (action === "delete" && eventId) {
-      await this.eventRepo.delete(eventId);
+      // Use deleteRecurring for proper handling of recurring events
+      const mode = deleteMode || "all";
+      await this.eventService.deleteRecurring(
+        eventId,
+        userId,
+        mode,
+        occurrenceDate,
+      );
+
+      // Build appropriate response message
+      let deleteDescription = "";
+      if (deleteMode === "single") {
+        deleteDescription = " (dieses Vorkommen)";
+      } else if (deleteMode === "future") {
+        deleteDescription = " (dieses und zukünftige Vorkommen)";
+      }
       content = event?.title
-        ? `Der Termin "${event.title}" wurde gelöscht.`
+        ? `Der Termin "${event.title}"${deleteDescription} wurde gelöscht.`
-        : "Der Termin wurde gelöscht.";
+        : `Der Termin${deleteDescription} wurde gelöscht.`;
     } else {
       content = "Ungültige Aktion.";
     }
@@ -343,9 +673,10 @@ export class ChatService {
     userId: string,
     conversationId: string,
     messageId: string,
+    proposalId: string,
   ): Promise<ChatResponse> {
-    // Update original message with respondedAction
+    // Update specific proposal with respondedAction
-    await this.chatRepo.updateMessage(messageId, { respondedAction: "reject" });
+    await this.chatRepo.updateProposalResponse(messageId, proposalId, "reject");
 
     // Save response message to DB
     const message = await this.chatRepo.createMessage(conversationId, {
@@ -389,4 +720,62 @@ export class ChatService {
 
     return this.chatRepo.getMessages(conversationId, options);
   }
+
+  async updateProposalEvent(
+    messageId: string,
+    proposalId: string,
+    event: CreateEventDTO,
+  ): Promise<ChatMessage | null> {
+    // Get the message to find the conversation
+    const message = await this.chatRepo.getMessageById(messageId);
+    if (!message) {
+      return null;
+    }
+
+    // Get the conversation to find the userId
+    const conversation = await this.chatRepo.getConversationById(
+      message.conversationId,
+    );
+    if (!conversation) {
+      return null;
+    }
+    const userId = conversation.userId;
+
+    // Get event times
+    const eventStart = new Date(event.startTime);
+    const eventEnd = new Date(event.endTime);
+
+    // Get day range for conflict checking
+    const dayStart = new Date(eventStart);
+    dayStart.setHours(0, 0, 0, 0);
+    const dayEnd = new Date(dayStart);
+    dayEnd.setDate(dayStart.getDate() + 1);
+
+    // Fetch events for the day
+    const dayEvents = await this.eventService.getByDateRange(
+      userId,
+      dayStart,
+      dayEnd,
+    );
+
+    // Check for time overlaps (use occurrenceStart/End for expanded recurring events)
+    const conflicts: ConflictingEvent[] = dayEvents
+      .filter(
+        (e) =>
+          new Date(e.occurrenceStart) < eventEnd &&
+          new Date(e.occurrenceEnd) > eventStart,
+      )
+      .map((e) => ({
+        title: e.title,
+        startTime: new Date(e.occurrenceStart),
+        endTime: new Date(e.occurrenceEnd),
+      }));
+
+    return this.chatRepo.updateProposalEvent(
+      messageId,
+      proposalId,
+      event,
+      conflicts.length > 0 ? conflicts : undefined,
+    );
+  }
 }

apps/server/src/services/EventService.ts

@@ -3,7 +3,9 @@ import {
   CreateEventDTO,
   UpdateEventDTO,
   ExpandedEvent,
-} from "@caldav/shared";
+  RecurringDeleteMode,
+} from "@calchat/shared";
+import { RRule, rrulestr } from "rrule";
 import { EventRepository } from "./interfaces";
 import { expandRecurringEvents } from "../utils/recurrenceExpander";
 
@@ -22,10 +24,21 @@ export class EventService {
     return event;
   }
 
+  async findByCaldavUUID(
+    userId: string,
+    caldavUUID: string,
+  ): Promise<CalendarEvent | null> {
+    return this.eventRepo.findByCaldavUUID(userId, caldavUUID);
+  }
+
   async getAll(userId: string): Promise<CalendarEvent[]> {
     return this.eventRepo.findByUserId(userId);
   }
 
+  async searchByTitle(userId: string, query: string): Promise<CalendarEvent[]> {
+    return this.eventRepo.searchByTitle(userId, query);
+  }
+
   async getByDateRange(
     userId: string,
     startDate: Date,
@@ -35,8 +48,8 @@ export class EventService {
     const allEvents = await this.eventRepo.findByUserId(userId);
 
     // Separate recurring and non-recurring events
-    const recurringEvents = allEvents.filter((e) => e.isRecurring);
+    const recurringEvents = allEvents.filter((e) => e.recurrenceRule);
-    const nonRecurringEvents = allEvents.filter((e) => !e.isRecurring);
+    const nonRecurringEvents = allEvents.filter((e) => !e.recurrenceRule);
 
     // Expand all events (recurring get multiple instances, non-recurring stay as-is)
     const expanded = expandRecurringEvents(
@@ -67,4 +80,96 @@ export class EventService {
     }
     return this.eventRepo.delete(id);
   }
+
+  /**
+   * Delete a recurring event with different modes:
+   * - 'all': Delete the entire event (all occurrences)
+   * - 'single': Add the occurrence date to exception list (EXDATE)
+   * - 'future': Set UNTIL in RRULE to stop future occurrences
+   *
+   * @returns Updated event for 'single'/'future' modes, null for 'all' mode or if not found
+   */
+  async deleteRecurring(
+    id: string,
+    userId: string,
+    mode: RecurringDeleteMode,
+    occurrenceDate?: string,
+  ): Promise<CalendarEvent | null> {
+    const event = await this.eventRepo.findById(id);
+    if (!event || event.userId !== userId) {
+      return null;
+    }
+
+    // For non-recurring events, always delete completely
+    if (!event.recurrenceRule) {
+      await this.eventRepo.delete(id);
+      return null;
+    }
+
+    switch (mode) {
+      case "all":
+        await this.eventRepo.delete(id);
+        return null;
+
+      case "single":
+        if (!occurrenceDate) {
+          throw new Error("occurrenceDate required for single delete mode");
+        }
+        // Add to exception dates
+        return this.eventRepo.addExceptionDate(id, occurrenceDate);
+
+      case "future":
+        if (!occurrenceDate) {
+          throw new Error("occurrenceDate required for future delete mode");
+        }
+        // Check if this is the first occurrence
+        const startDateKey = this.formatDateKey(new Date(event.startTime));
+        if (occurrenceDate <= startDateKey) {
+          // Deleting from first occurrence = delete all
+          await this.eventRepo.delete(id);
+          return null;
+        }
+        // Set UNTIL to the day before the occurrence
+        const updatedRule = this.addUntilToRRule(
+          event.recurrenceRule,
+          occurrenceDate,
+        );
+        return this.eventRepo.update(id, { recurrenceRule: updatedRule });
+
+      default:
+        throw new Error(`Unknown delete mode: ${mode}`);
+    }
+  }
+
+  /**
+   * Add or replace UNTIL clause in an RRULE string.
+   * The UNTIL is set to 23:59:59 of the day before the occurrence date.
+   */
+  private addUntilToRRule(ruleString: string, occurrenceDate: string): string {
+    // Normalize: ensure we have RRULE: prefix for parsing
+    const normalizedRule = ruleString.replace(/^RRULE:/i, "");
+    const parsedRule = rrulestr(`RRULE:${normalizedRule}`);
+
+    // Calculate the day before the occurrence at 23:59:59
+    const untilDate = new Date(occurrenceDate);
+    untilDate.setDate(untilDate.getDate() - 1);
+    untilDate.setHours(23, 59, 59, 0);
+
+    // Create new rule with UNTIL, removing COUNT (they're mutually exclusive)
+    const newRule = new RRule({
+      ...parsedRule.options,
+      count: undefined,
+      until: untilDate,
+    });
+
+    // toString() returns "RRULE:...", we store without prefix
+    return newRule.toString().replace(/^RRULE:/, "");
+  }
+
+  private formatDateKey(date: Date): string {
+    const year = date.getFullYear();
+    const month = String(date.getMonth() + 1).padStart(2, "0");
+    const day = String(date.getDate()).padStart(2, "0");
+    return `${year}-${month}-${day}`;
+  }
 }

apps/server/src/services/interfaces/AIProvider.ts

@@ -1,19 +1,29 @@
 import {
-  CalendarEvent,
   ChatMessage,
   ProposedEventChange,
-} from "@caldav/shared";
+  ExpandedEvent,
+  CalendarEvent,
+} from "@calchat/shared";
 
 export interface AIContext {
   userId: string;
   conversationHistory: ChatMessage[];
-  existingEvents: CalendarEvent[];
   currentDate: Date;
+  // Callback to load events from a specific date range
+  // Returns ExpandedEvent[] with occurrenceStart/occurrenceEnd for recurring events
+  fetchEventsInRange: (
+    startDate: Date,
+    endDate: Date,
+  ) => Promise<ExpandedEvent[]>;
+  // Callback to search events by title
+  searchEvents: (query: string) => Promise<CalendarEvent[]>;
+  // Callback to fetch a single event by ID
+  fetchEventById: (eventId: string) => Promise<CalendarEvent | null>;
 }
 
 export interface AIResponse {
   content: string;
-  proposedChange?: ProposedEventChange;
+  proposedChanges?: ProposedEventChange[];
 }
 
 export interface AIProvider {

apps/server/src/services/interfaces/CaldavRepository.ts

@@ -0,0 +1,7 @@
+import { CaldavConfig } from "@calchat/shared";
+
+export interface CaldavRepository {
+  findByUserId(userId: string): Promise<CaldavConfig | null>;
+  createOrUpdate(config: CaldavConfig): Promise<CaldavConfig>;
+  deleteByUserId(userId: string): Promise<boolean>;
+}

apps/server/src/services/interfaces/ChatRepository.ts

@@ -2,13 +2,16 @@ import {
   ChatMessage,
   Conversation,
   CreateMessageDTO,
+  CreateEventDTO,
   GetMessagesOptions,
   UpdateMessageDTO,
-} from "@caldav/shared";
+  ConflictingEvent,
+} from "@calchat/shared";
 
 export interface ChatRepository {
   // Conversations
   getConversationsByUser(userId: string): Promise<Conversation[]>;
+  getConversationById(conversationId: string): Promise<Conversation | null>;
   createConversation(userId: string): Promise<Conversation>;
 
   // Messages (cursor-based pagination)
@@ -26,4 +29,19 @@ export interface ChatRepository {
     messageId: string,
     updates: UpdateMessageDTO,
   ): Promise<ChatMessage | null>;
+
+  updateProposalResponse(
+    messageId: string,
+    proposalId: string,
+    respondedAction: "confirm" | "reject",
+  ): Promise<ChatMessage | null>;
+
+  updateProposalEvent(
+    messageId: string,
+    proposalId: string,
+    event: CreateEventDTO,
+    conflictingEvents?: ConflictingEvent[],
+  ): Promise<ChatMessage | null>;
+
+  getMessageById(messageId: string): Promise<ChatMessage | null>;
 }

apps/server/src/services/interfaces/EventRepository.ts

@@ -1,4 +1,4 @@
-import { CalendarEvent, CreateEventDTO, UpdateEventDTO } from "@caldav/shared";
+import { CalendarEvent, CreateEventDTO, UpdateEventDTO } from "@calchat/shared";
 
 export interface EventRepository {
   findById(id: string): Promise<CalendarEvent | null>;
@@ -8,7 +8,13 @@ export interface EventRepository {
     startDate: Date,
     endDate: Date,
   ): Promise<CalendarEvent[]>;
+  findByCaldavUUID(
+    userId: string,
+    caldavUUID: string,
+  ): Promise<CalendarEvent | null>;
+  searchByTitle(userId: string, query: string): Promise<CalendarEvent[]>;
   create(userId: string, data: CreateEventDTO): Promise<CalendarEvent>;
   update(id: string, data: UpdateEventDTO): Promise<CalendarEvent | null>;
   delete(id: string): Promise<boolean>;
+  addExceptionDate(id: string, date: string): Promise<CalendarEvent | null>;
 }

apps/server/src/services/interfaces/UserRepository.ts

@@ -1,13 +1,14 @@
-import { User } from "@caldav/shared";
+import { User } from "@calchat/shared";
 
 export interface CreateUserData {
   email: string;
-  displayName: string;
+  userName: string;
   passwordHash: string;
 }
 
 export interface UserRepository {
   findById(id: string): Promise<User | null>;
   findByEmail(email: string): Promise<User | null>;
+  findByUserName(userName: string): Promise<User | null>;
   create(data: CreateUserData): Promise<User>;
 }

apps/server/src/utils/eventFormatters.ts

@@ -5,8 +5,8 @@ import {
   DAY_TO_GERMAN_SHORT,
   MONTH_TO_GERMAN,
   ExpandedEvent,
-} from "@caldav/shared";
+} from "@calchat/shared";
-import { EventRepository } from "../services/interfaces";
+import { EventService } from "../services/EventService";
 import { expandRecurringEvents } from "./recurrenceExpander";
 
 // Private formatting helpers
@@ -107,13 +107,13 @@ function formatMonthText(events: ExpandedEvent[], monthName: string): string {
  * Recurring events are expanded to show all occurrences within the range.
  */
 export async function getWeeksOverview(
-  eventRepo: EventRepository,
+  eventService: EventService,
   userId: string,
   weeks: number,
 ): Promise<string> {
   const now = new Date();
   const endDate = new Date(now.getTime() + weeks * 7 * 24 * 60 * 60 * 1000);
-  const events = await eventRepo.findByUserId(userId);
+  const events = await eventService.getAll(userId);
   const expanded = expandRecurringEvents(events, now, endDate);
   return formatWeeksText(expanded, weeks);
 }
@@ -123,14 +123,14 @@ export async function getWeeksOverview(
  * Recurring events are expanded to show all occurrences within the month.
  */
 export async function getMonthOverview(
-  eventRepo: EventRepository,
+  eventService: EventService,
   userId: string,
   year: number,
   month: number,
 ): Promise<string> {
   const startOfMonth = new Date(year, month, 1);
   const endOfMonth = new Date(year, month + 1, 0, 23, 59, 59);
-  const events = await eventRepo.findByUserId(userId);
+  const events = await eventService.getAll(userId);
   const expanded = expandRecurringEvents(events, startOfMonth, endOfMonth);
   const monthName = MONTH_TO_GERMAN[MONTHS[month]];
   return formatMonthText(expanded, monthName);