Session-Historie: Nachrichten werden persistent gespeichert

- Neue messages-Tabelle in SQLite für Chat-Nachrichten
- save_message, load_messages, clear_messages Tauri-Commands
- User-Nachrichten werden beim Senden sofort gespeichert
- Assistant-Nachrichten werden nach Abschluss gespeichert
- Beim Session-Wechsel werden Nachrichten aus DB geladen
- currentSessionId Store für Session-Tracking

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src-tauri/src/db.rs

@@ -27,6 +27,17 @@ pub struct Session {
     pub last_message: Option<String>,
 }
 
+/// Eine Chat-Nachricht
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
+pub struct ChatMessage {
+    pub id: String,
+    pub session_id: String,
+    pub role: String,  // "user", "assistant", "system"
+    pub content: String,
+    pub model: Option<String>,
+    pub timestamp: String,
+}
+
 /// Datenbank-Wrapper
 pub struct Database {
     conn: Connection,
@@ -141,6 +152,18 @@ impl Database {
                 value TEXT NOT NULL,
                 updated_at TEXT NOT NULL
             );
+
+            -- Chat-Nachrichten
+            CREATE TABLE IF NOT EXISTS messages (
+                id TEXT PRIMARY KEY,
+                session_id TEXT NOT NULL,
+                role TEXT NOT NULL,
+                content TEXT NOT NULL,
+                model TEXT,
+                timestamp TEXT NOT NULL,
+                FOREIGN KEY (session_id) REFERENCES sessions(id) ON DELETE CASCADE
+            );
+            CREATE INDEX IF NOT EXISTS idx_messages_session ON messages(session_id, timestamp);
             ",
         )?;
         Ok(())
@@ -488,10 +511,58 @@ impl Database {
 
     /// Löscht eine Session
     pub fn delete_session(&self, id: &str) -> SqlResult<()> {
+        // Erst Nachrichten löschen (wegen Foreign Key)
+        self.conn.execute("DELETE FROM messages WHERE session_id = ?1", params![id])?;
         self.conn.execute("DELETE FROM sessions WHERE id = ?1", params![id])?;
         Ok(())
     }
 
+    // ============ Messages ============
+
+    /// Speichert eine Nachricht
+    pub fn save_message(&self, msg: &ChatMessage) -> SqlResult<()> {
+        self.conn.execute(
+            "INSERT OR REPLACE INTO messages (id, session_id, role, content, model, timestamp)
+             VALUES (?1, ?2, ?3, ?4, ?5, ?6)",
+            params![
+                msg.id,
+                msg.session_id,
+                msg.role,
+                msg.content,
+                msg.model,
+                msg.timestamp,
+            ],
+        )?;
+        Ok(())
+    }
+
+    /// Lädt alle Nachrichten einer Session
+    pub fn load_messages(&self, session_id: &str) -> SqlResult<Vec<ChatMessage>> {
+        let mut stmt = self.conn.prepare(
+            "SELECT id, session_id, role, content, model, timestamp
+             FROM messages WHERE session_id = ?1 ORDER BY timestamp ASC"
+        )?;
+
+        let messages = stmt.query_map(params![session_id], |row| {
+            Ok(ChatMessage {
+                id: row.get(0)?,
+                session_id: row.get(1)?,
+                role: row.get(2)?,
+                content: row.get(3)?,
+                model: row.get(4)?,
+                timestamp: row.get(5)?,
+            })
+        })?.collect::<SqlResult<Vec<_>>>()?;
+
+        Ok(messages)
+    }
+
+    /// Löscht alle Nachrichten einer Session
+    pub fn clear_messages(&self, session_id: &str) -> SqlResult<()> {
+        self.conn.execute("DELETE FROM messages WHERE session_id = ?1", params![session_id])?;
+        Ok(())
+    }
+
     // ============ Settings ============
 
     /// Speichert eine Einstellung
@@ -637,3 +708,27 @@ pub async fn get_all_settings(app: AppHandle) -> Result<Vec<(String, String)>, S
     let db = state.lock().unwrap();
     db.get_all_settings().map_err(|e| e.to_string())
 }
+
+/// Nachricht speichern
+#[tauri::command]
+pub async fn save_message(app: AppHandle, message: ChatMessage) -> Result<(), String> {
+    let state = app.state::<DbState>();
+    let db = state.lock().unwrap();
+    db.save_message(&message).map_err(|e| e.to_string())
+}
+
+/// Nachrichten einer Session laden
+#[tauri::command]
+pub async fn load_messages(app: AppHandle, session_id: String) -> Result<Vec<ChatMessage>, String> {
+    let state = app.state::<DbState>();
+    let db = state.lock().unwrap();
+    db.load_messages(&session_id).map_err(|e| e.to_string())
+}
+
+/// Alle Nachrichten einer Session löschen
+#[tauri::command]
+pub async fn clear_messages(app: AppHandle, session_id: String) -> Result<(), String> {
+    let state = app.state::<DbState>();
+    let db = state.lock().unwrap();
+    db.clear_messages(&session_id).map_err(|e| e.to_string())
+}

src-tauri/src/lib.rs

@@ -57,6 +57,10 @@ pub fn run() {
             session::resume_session,
             session::get_active_session,
             session::set_claude_session_id,
+            // Messages
+            db::save_message,
+            db::load_messages,
+            db::clear_messages,
         ])
         .setup(|app| {
             let handle = app.handle().clone();

src/lib/components/ChatPanel.svelte

@@ -1,8 +1,9 @@
 <script lang="ts">
 	import { invoke } from '@tauri-apps/api/core';
-	import { messages, currentInput, isProcessing, addMessage } from '$lib/stores/app';
+	import { messages, currentInput, isProcessing, addMessage, currentSessionId, messageToDb, type Message } from '$lib/stores/app';
 	import { marked } from 'marked';
-	import { tick } from 'svelte';
+	import { tick, onDestroy } from 'svelte';
+	import { get } from 'svelte/store';
 
 	marked.setOptions({ breaks: true, gfm: true });
 
@@ -25,11 +26,56 @@
 
 	$: if ($messages.length) scrollToBottom();
 
+	// Nachricht in DB speichern
+	async function saveMessageToDb(msg: Message) {
+		const sessionId = get(currentSessionId);
+		if (!sessionId) return;
+
+		try {
+			const dbMsg = messageToDb(msg, sessionId);
+			await invoke('save_message', { message: dbMsg });
+		} catch (err) {
+			console.error('Fehler beim Speichern der Nachricht:', err);
+		}
+	}
+
+	// Neue Nachrichten automatisch speichern
+	let lastMessageCount = 0;
+	const unsubscribe = messages.subscribe(async (msgs) => {
+		if (msgs.length > lastMessageCount && lastMessageCount > 0) {
+			// Neue Nachricht(en) hinzugefügt
+			const newMessages = msgs.slice(lastMessageCount);
+			for (const msg of newMessages) {
+				// Nur speichern wenn Nachricht Content hat (nicht die leere Streaming-Nachricht)
+				if (msg.content && msg.content.trim()) {
+					await saveMessageToDb(msg);
+				}
+			}
+		}
+		lastMessageCount = msgs.length;
+	});
+
+	onDestroy(() => {
+		unsubscribe();
+	});
+
 	async function sendMessage() {
 		const text = $currentInput.trim();
 		if (!text || $isProcessing) return;
 
-		addMessage('user', text);
+		// Nachricht hinzufügen (wird durch den Store-Subscriber gespeichert)
+		const msgId = crypto.randomUUID();
+		const msg: Message = {
+			id: msgId,
+			role: 'user',
+			content: text,
+			timestamp: new Date(),
+		};
+		messages.update((msgs) => [...msgs, msg]);
+
+		// Sofort speichern (nicht auf Subscriber warten)
+		await saveMessageToDb(msg);
+
 		$currentInput = '';
 		$isProcessing = true;
 

src/lib/components/SessionList.svelte

@@ -1,7 +1,7 @@
 <script lang="ts">
 	import { onMount } from 'svelte';
 	import { invoke } from '@tauri-apps/api/core';
-	import { messages, clearAll, isProcessing } from '$lib/stores/app';
+	import { messages, clearAll, isProcessing, currentSessionId, setMessagesFromDb, type DbMessage } from '$lib/stores/app';
 
 	interface Session {
 		id: string;
@@ -29,12 +29,28 @@
 			sessions = await invoke('list_sessions', { limit: 50 });
 			const active: Session | null = await invoke('get_active_session');
 			activeSessionId = active?.id || null;
+			$currentSessionId = activeSessionId;
+
+			// Wenn aktive Session existiert, Nachrichten laden
+			if (activeSessionId) {
+				await loadSessionMessages(activeSessionId);
+			}
 		} catch (err) {
 			console.error('Fehler beim Laden der Sessions:', err);
 		}
 		loading = false;
 	}
 
+	async function loadSessionMessages(sessionId: string) {
+		try {
+			const dbMessages: DbMessage[] = await invoke('load_messages', { sessionId });
+			setMessagesFromDb(dbMessages);
+			console.log(`📨 ${dbMessages.length} Nachrichten geladen`);
+		} catch (err) {
+			console.error('Fehler beim Laden der Nachrichten:', err);
+		}
+	}
+
 	onMount(() => {
 		loadSessions();
 	});
@@ -47,6 +63,7 @@
 				workingDir: null,
 			});
 			activeSessionId = session.id;
+			$currentSessionId = session.id;
 			clearAll();
 			newTitle = '';
 			showNewForm = false;
@@ -61,8 +78,10 @@
 		try {
 			const session: Session = await invoke('resume_session', { id });
 			activeSessionId = session.id;
+			$currentSessionId = session.id;
 			clearAll();
-			// TODO: Nachrichten aus Session-Historie laden
+			// Nachrichten aus DB laden
+			await loadSessionMessages(session.id);
 		} catch (err) {
 			console.error('Fehler:', err);
 		}

src/lib/stores/app.ts

@@ -51,6 +51,7 @@ export const isProcessing = writable(false);
 export const currentInput = writable('');
 export const selectedAgentId = writable<string | null>(null);
 export const currentModel = writable('');
+export const currentSessionId = writable<string | null>(null);
 
 // Session-Statistiken (kumuliert)
 export const sessionStats = writable({
@@ -156,3 +157,41 @@ export function clearAll() {
 	messages.set([]);
 	isProcessing.set(false);
 }
+
+// DB-Nachricht Format (für Tauri)
+export interface DbMessage {
+	id: string;
+	session_id: string;
+	role: string;
+	content: string;
+	model: string | null;
+	timestamp: string;
+}
+
+// Konvertierung: Store → DB
+export function messageToDb(msg: Message, sessionId: string): DbMessage {
+	return {
+		id: msg.id,
+		session_id: sessionId,
+		role: msg.role,
+		content: msg.content,
+		model: msg.model || null,
+		timestamp: msg.timestamp.toISOString(),
+	};
+}
+
+// Konvertierung: DB → Store
+export function dbToMessage(db: DbMessage): Message {
+	return {
+		id: db.id,
+		role: db.role as Message['role'],
+		content: db.content,
+		model: db.model || undefined,
+		timestamp: new Date(db.timestamp),
+	};
+}
+
+// Nachrichten aus DB in Store laden
+export function setMessagesFromDb(dbMessages: DbMessage[]) {
+	messages.set(dbMessages.map(dbToMessage));
+}

src/lib/stores/events.ts

@@ -2,6 +2,8 @@
 // Empfängt Events vom Tauri-Backend und aktualisiert die Stores
 
 import { listen, type UnlistenFn } from '@tauri-apps/api/event';
+import { invoke } from '@tauri-apps/api/core';
+import { get } from 'svelte/store';
 import {
 	agents,
 	toolCalls,
@@ -14,7 +16,10 @@ import {
 	completeToolCall,
 	clearAll,
 	currentModel,
-	sessionStats
+	sessionStats,
+	currentSessionId,
+	messageToDb,
+	type Message
 } from './app';
 
 // Event-Typen vom Backend
@@ -53,6 +58,20 @@ let listeners: UnlistenFn[] = [];
 // Streaming: ID der aktuellen Live-Nachricht
 let streamingMessageId: string | null = null;
 
+// Nachricht in DB speichern
+async function saveMessageToDb(msg: Message) {
+	const sessionId = get(currentSessionId);
+	if (!sessionId) return;
+
+	try {
+		const dbMsg = messageToDb(msg, sessionId);
+		await invoke('save_message', { message: dbMsg });
+		console.log('💾 Nachricht gespeichert:', msg.role);
+	} catch (err) {
+		console.error('Fehler beim Speichern der Nachricht:', err);
+	}
+}
+
 // Events initialisieren
 export async function initEventListeners(): Promise<void> {
 	console.log('🎧 Initialisiere Event-Listener...');
@@ -161,15 +180,31 @@ export async function initEventListeners(): Promise<void> {
 
 	// Ergebnis (Kosten, Token, Modell)
 	listeners.push(
-		await listen<ResultEvent>('claude-result', (event) => {
+		await listen<ResultEvent>('claude-result', async (event) => {
 			const { cost, tokens, session_id, model } = event.payload;
 			console.log('📊 Ergebnis:', { cost: cost ? `$${cost.toFixed(4)}` : '-', tokens, model });
 
-			// Modell an die Streaming-Nachricht anhängen
+			// Modell an die Streaming-Nachricht anhängen und speichern
-			if (model && streamingMessageId) {
+			if (streamingMessageId) {
-				messages.update((msgs) =>
+				let finalMessage: Message | null = null;
-					msgs.map((m) => m.id === streamingMessageId ? { ...m, model } : m)
+
-				);
+				messages.update((msgs) => {
+					return msgs.map((m) => {
+						if (m.id === streamingMessageId) {
+							finalMessage = { ...m, model: model || m.model };
+							return finalMessage;
+						}
+						return m;
+					});
+				});
+
+				// Nachricht in DB speichern (nur wenn Content vorhanden)
+				if (finalMessage && finalMessage.content && finalMessage.content.trim()) {
+					await saveMessageToDb(finalMessage);
+				}
+			}
+
+			if (model) {
 				currentModel.set(model);
 			}