Add settings management with Bundesland selection and holiday calculations

server.js

@@ -40,6 +40,20 @@ try {
   console.error('Error during migration:', error);
 }
 
+// Create settings table if it doesn't exist
+try {
+  db.exec(`
+    CREATE TABLE IF NOT EXISTS settings (
+      key TEXT PRIMARY KEY,
+      value TEXT NOT NULL,
+      updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
+    )
+  `);
+  console.log('Settings table ready');
+} catch (error) {
+  console.error('Error creating settings table:', error);
+}
+
 console.log('Database initialized successfully');
 
 // ============================================
@@ -334,6 +348,71 @@ app.get('/api/export', (req, res) => {
   }
 });
 
+// ============================================
+// SETTINGS ENDPOINTS
+// ============================================
+
+// Get a setting by key
+app.get('/api/settings/:key', (req, res) => {
+  try {
+    const { key } = req.params;
+    const stmt = db.prepare('SELECT value FROM settings WHERE key = ?');
+    const result = stmt.get(key);
+    
+    if (!result) {
+      return res.status(404).json({ error: 'Setting not found' });
+    }
+    
+    res.json({ key, value: result.value });
+  } catch (error) {
+    console.error('Error getting setting:', error);
+    res.status(500).json({ error: 'Failed to get setting' });
+  }
+});
+
+// Set a setting
+app.post('/api/settings', (req, res) => {
+  try {
+    const { key, value } = req.body;
+    
+    if (!key || value === undefined) {
+      return res.status(400).json({ error: 'Key and value are required' });
+    }
+    
+    const stmt = db.prepare(`
+      INSERT INTO settings (key, value, updated_at) 
+      VALUES (?, ?, CURRENT_TIMESTAMP)
+      ON CONFLICT(key) DO UPDATE SET 
+        value = excluded.value,
+        updated_at = CURRENT_TIMESTAMP
+    `);
+    
+    stmt.run(key, value);
+    res.json({ key, value });
+  } catch (error) {
+    console.error('Error setting setting:', error);
+    res.status(500).json({ error: 'Failed to set setting' });
+  }
+});
+
+// Get all settings
+app.get('/api/settings', (req, res) => {
+  try {
+    const stmt = db.prepare('SELECT key, value FROM settings');
+    const settings = stmt.all();
+    
+    const result = {};
+    settings.forEach(s => {
+      result[s.key] = s.value;
+    });
+    
+    res.json(result);
+  } catch (error) {
+    console.error('Error getting settings:', error);
+    res.status(500).json({ error: 'Failed to get settings' });
+  }
+});
+
 // Start server
 app.listen(PORT, () => {
   console.log(`Server is running on http://localhost:${PORT}`);