fix: eraser tool works on polygon areas and line edges, not just vertices

next.config.js

@@ -49,9 +49,9 @@ const nextConfig = {
               "default-src 'self'",
               "script-src 'self' 'unsafe-inline' 'unsafe-eval' blob:",
               "style-src 'self' 'unsafe-inline'",
-              "img-src 'self' data: blob: https://*.tile.openstreetmap.org https://api.maptiler.com http://localhost:9000 http://minio:9000",
+              "img-src 'self' data: blob: https://*.tile.openstreetmap.org https://api.maptiler.com https://server.arcgisonline.com https://wmts.geo.admin.ch https://wmts0.geo.admin.ch https://wmts1.geo.admin.ch https://wmts2.geo.admin.ch https://wmts3.geo.admin.ch https://wmts4.geo.admin.ch http://localhost:9000 http://minio:9000",
               "font-src 'self' data:",
-              "connect-src 'self' ws: wss: https://api.maptiler.com https://*.tile.openstreetmap.org https://api.open-meteo.com",
+              "connect-src 'self' ws: wss: https://api.maptiler.com https://*.tile.openstreetmap.org https://api.open-meteo.com https://server.arcgisonline.com https://wmts.geo.admin.ch https://wmts0.geo.admin.ch https://wmts1.geo.admin.ch https://wmts2.geo.admin.ch https://wmts3.geo.admin.ch https://wmts4.geo.admin.ch",
               "frame-ancestors 'self'",
               "base-uri 'self'",
               "form-action 'self'",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "lageplan",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "description": "Feuerwehr Lageplan - Krokier-App für Einsatzdokumentation",
   "private": true,
   "scripts": {

public/manifest.json

@@ -20,7 +20,13 @@
       "src": "/logo-icon.png",
       "sizes": "192x192",
       "type": "image/png",
-      "purpose": "any maskable"
+      "purpose": "any"
+    },
+    {
+      "src": "/logo-icon-maskable.png",
+      "sizes": "192x192",
+      "type": "image/png",
+      "purpose": "maskable"
     }
   ],
   "screenshots": [],

public/sw.js

@@ -1,6 +1,10 @@
-const TILE_CACHE = 'lageplan-tiles-v2'
-const STATIC_CACHE = 'lageplan-static-v2'
-const APP_CACHE = 'lageplan-app-v2'
+const TILE_CACHE = 'lageplan-tiles-v3'
+const STATIC_CACHE = 'lageplan-static-v3'
+const APP_CACHE = 'lageplan-app-v3'
+const API_CACHE = 'lageplan-api-v3'
+
+// API routes that should be cached for offline use
+const CACHEABLE_API = ['/api/icons', '/api/hose-types', '/api/dictionary']
 
 // Pre-cache essential app shell on install
 self.addEventListener('install', (event) => {
@@ -8,6 +12,8 @@ self.addEventListener('install', (event) => {
     caches.open(APP_CACHE).then((cache) =>
       cache.addAll([
         '/app',
+        '/login',
+        '/',
         '/logo.svg',
         '/logo-icon.png',
         '/manifest.json',
@@ -17,7 +23,6 @@ self.addEventListener('install', (event) => {
   self.skipWaiting()
 })
 
-// Cache strategy: Network First for API, Cache First for tiles, Stale While Revalidate for static assets
 self.addEventListener('fetch', (event) => {
   const url = event.request.url
   const { pathname } = new URL(url)
@@ -25,19 +30,71 @@ self.addEventListener('fetch', (event) => {
   // Skip non-GET requests
   if (event.request.method !== 'GET') return
 
-  // API requests: network only (don't cache dynamic data)
+  // Never intercept Socket.IO — let it pass through directly
+  if (pathname.startsWith('/socket.io')) return
+
+  // Cacheable API routes: Network First with cache fallback (icons, hose-types, dictionary)
+  if (CACHEABLE_API.some(p => pathname.startsWith(p))) {
+    event.respondWith(
+      caches.open(API_CACHE).then((cache) =>
+        fetch(event.request).then((response) => {
+          if (response.ok) cache.put(event.request, response.clone())
+          return response
+        }).catch(() =>
+          cache.match(event.request).then((cached) => cached || new Response('{"error":"offline"}', {
+            status: 503, headers: { 'Content-Type': 'application/json' }
+          }))
+        )
+      )
+    )
+    return
+  }
+
+  // Projects API: Network First with cache fallback
+  if (pathname === '/api/projects' || pathname.match(/^\/api\/projects\/[^/]+$/)) {
+    event.respondWith(
+      caches.open(API_CACHE).then((cache) =>
+        fetch(event.request).then((response) => {
+          if (response.ok) cache.put(event.request, response.clone())
+          return response
+        }).catch(() =>
+          cache.match(event.request).then((cached) => cached || new Response('{"error":"offline"}', {
+            status: 503, headers: { 'Content-Type': 'application/json' }
+          }))
+        )
+      )
+    )
+    return
+  }
+
+  // Features API: Network First with cache fallback
+  if (pathname.match(/^\/api\/projects\/[^/]+\/features$/)) {
+    event.respondWith(
+      caches.open(API_CACHE).then((cache) =>
+        fetch(event.request).then((response) => {
+          if (response.ok) cache.put(event.request, response.clone())
+          return response
+        }).catch(() =>
+          cache.match(event.request).then((cached) => cached || new Response('{"error":"offline"}', {
+            status: 503, headers: { 'Content-Type': 'application/json' }
+          }))
+        )
+      )
+    )
+    return
+  }
+
+  // Other API requests: network only
   if (pathname.startsWith('/api/')) return
 
-  // Cache map tiles from OpenStreetMap (Cache First)
+  // Cache map tiles from OpenStreetMap / MapTiler (Cache First — tiles don't change)
   if (url.includes('tile.openstreetmap.org') || url.includes('api.maptiler.com')) {
     event.respondWith(
       caches.open(TILE_CACHE).then((cache) =>
         cache.match(event.request).then((cached) => {
           if (cached) return cached
           return fetch(event.request).then((response) => {
-            if (response.ok) {
-              cache.put(event.request, response.clone())
-            }
+            if (response.ok) cache.put(event.request, response.clone())
             return response
           }).catch(() => new Response('', { status: 503 }))
         })
@@ -46,7 +103,23 @@ self.addEventListener('fetch', (event) => {
     return
   }
 
-  // Static assets (JS, CSS, images): Stale While Revalidate
+  // Next.js build chunks (_next/static): Cache First (hashed filenames = immutable)
+  if (pathname.startsWith('/_next/static/')) {
+    event.respondWith(
+      caches.open(STATIC_CACHE).then((cache) =>
+        cache.match(event.request).then((cached) => {
+          if (cached) return cached
+          return fetch(event.request).then((response) => {
+            if (response.ok) cache.put(event.request, response.clone())
+            return response
+          }).catch(() => new Response('', { status: 503 }))
+        })
+      )
+    )
+    return
+  }
+
+  // Other static assets (JS, CSS, images, fonts): Stale While Revalidate
   if (pathname.match(/\.(js|css|png|jpg|jpeg|svg|ico|woff2?)$/)) {
     event.respondWith(
       caches.open(STATIC_CACHE).then((cache) =>
@@ -62,8 +135,8 @@ self.addEventListener('fetch', (event) => {
     return
   }
 
-  // App pages: Network First with cache fallback
-  if (pathname === '/app' || pathname === '/' || pathname.startsWith('/app')) {
+  // App pages / navigation: Network First with cache fallback
+  if (event.request.mode === 'navigate' || pathname === '/app' || pathname === '/' || pathname.startsWith('/app')) {
     event.respondWith(
       fetch(event.request).then((response) => {
         if (response.ok) {
@@ -81,7 +154,7 @@ self.addEventListener('fetch', (event) => {
 
 // Clean old caches on activation
 self.addEventListener('activate', (event) => {
-  const currentCaches = [TILE_CACHE, STATIC_CACHE, APP_CACHE]
+  const currentCaches = [TILE_CACHE, STATIC_CACHE, APP_CACHE, API_CACHE]
   event.waitUntil(
     caches.keys().then((keys) =>
       Promise.all(
@@ -92,3 +165,23 @@ self.addEventListener('activate', (event) => {
     ).then(() => self.clients.claim())
   )
 })
+
+// Listen for sync events (Background Sync for queued saves)
+self.addEventListener('sync', (event) => {
+  if (event.tag === 'sync-saves') {
+    event.waitUntil(syncQueuedSaves())
+  }
+})
+
+// Process queued saves from IndexedDB/localStorage
+async function syncQueuedSaves() {
+  try {
+    const clients = await self.clients.matchAll()
+    clients.forEach(client => client.postMessage({ type: 'SYNC_START' }))
+
+    // Read queue from a BroadcastChannel or let the main thread handle it
+    clients.forEach(client => client.postMessage({ type: 'FLUSH_SYNC_QUEUE' }))
+  } catch (e) {
+    console.error('[SW] Sync error:', e)
+  }
+}

src/app/app/page.tsx

@@ -19,9 +19,10 @@ import { Button } from '@/components/ui/button'
 import { Dialog, DialogContent, DialogHeader, DialogTitle } from '@/components/ui/dialog'
 import { JournalView } from '@/components/journal/journal-view'
 import { jsPDF } from 'jspdf'
-import { Lock, Unlock, Eye, AlertTriangle } from 'lucide-react'
-import { getSocket } from '@/lib/socket'
+import { Lock, Unlock, Eye, AlertTriangle, WifiOff } from 'lucide-react'
+import { getSocket, setSocketRoom } from '@/lib/socket'
 import { CustomDragLayer } from '@/components/map/custom-drag-layer'
+import { addToSyncQueue, flushSyncQueue, getSyncQueue, isOnline as checkOnline } from '@/lib/offline-sync'
 
 export interface Project {
   id: string
@@ -366,6 +367,54 @@ export default function AppPage() {
   // Ref to access the map for export
   const mapRef = useRef<any>(null)
 
+  // Offline detection
+  const [isOffline, setIsOffline] = useState(false)
+  const [syncQueueCount, setSyncQueueCount] = useState(0)
+
+  useEffect(() => {
+    setIsOffline(!checkOnline())
+    setSyncQueueCount(getSyncQueue().length)
+
+    const goOffline = () => {
+      setIsOffline(true)
+      toast({ title: 'Offline-Modus', description: 'Änderungen werden lokal gespeichert und beim Reconnect synchronisiert.' })
+    }
+    const goOnline = async () => {
+      setIsOffline(false)
+      const queue = getSyncQueue()
+      if (queue.length > 0) {
+        toast({ title: 'Verbindung wiederhergestellt', description: `${queue.length} Änderung(en) werden synchronisiert...` })
+        const result = await flushSyncQueue()
+        setSyncQueueCount(getSyncQueue().length)
+        if (result.success > 0) {
+          toast({ title: 'Synchronisiert', description: `${result.success} Änderung(en) erfolgreich gespeichert.` })
+        }
+        if (result.failed > 0) {
+          toast({ title: 'Sync-Fehler', description: `${result.failed} Änderung(en) konnten nicht gespeichert werden.`, variant: 'destructive' })
+        }
+      } else {
+        toast({ title: 'Wieder online' })
+      }
+    }
+
+    window.addEventListener('offline', goOffline)
+    window.addEventListener('online', goOnline)
+
+    // Listen for SW sync messages
+    if ('serviceWorker' in navigator) {
+      navigator.serviceWorker.addEventListener('message', (event) => {
+        if (event.data?.type === 'FLUSH_SYNC_QUEUE') {
+          flushSyncQueue().then(() => setSyncQueueCount(getSyncQueue().length))
+        }
+      })
+    }
+
+    return () => {
+      window.removeEventListener('offline', goOffline)
+      window.removeEventListener('online', goOnline)
+    }
+  }, [])
+
   // Undo/Redo history
   const undoStackRef = useRef<DrawFeature[][]>([])
   const redoStackRef = useRef<DrawFeature[][]>([])
@@ -458,27 +507,31 @@ export default function AppPage() {
   const socketRef = useRef<any>(null)
   const prevProjectIdRef = useRef<string | null>(null)
 
-  // Throttled socket broadcast for near-real-time sync (1.5s instead of 10s auto-save)
+  // Throttled socket broadcast for near-real-time sync
   const lastEmitRef = useRef(0)
   const emitTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const currentProjectRef = useRef(currentProject)
+  useEffect(() => { currentProjectRef.current = currentProject }, [currentProject])
+
   const broadcastFeatures = useCallback((feats: DrawFeature[]) => {
-    if (!socketRef.current || !currentProject?.id || !isEditingByMe) return
+    const proj = currentProjectRef.current
+    if (!socketRef.current || !proj?.id || !isEditingByMeRef.current) return
     const now = Date.now()
     const emit = () => {
       socketRef.current?.emit('features-updated', {
-        projectId: currentProject!.id,
+        projectId: proj!.id,
         features: feats,
       })
       lastEmitRef.current = Date.now()
     }
-    // Throttle: emit at most every 1.5 seconds
-    if (now - lastEmitRef.current > 1500) {
+    // Throttle: emit at most every 800ms for snappier sync
+    if (now - lastEmitRef.current > 800) {
       emit()
     } else {
       if (emitTimerRef.current) clearTimeout(emitTimerRef.current)
-      emitTimerRef.current = setTimeout(emit, 1500 - (now - lastEmitRef.current))
+      emitTimerRef.current = setTimeout(emit, 800 - (now - lastEmitRef.current))
     }
-  }, [currentProject?.id, isEditingByMe])
+  }, [])
   const isEditingByMeRef = useRef(false)
 
   // Keep ref in sync with state
@@ -497,6 +550,7 @@ export default function AppPage() {
       socket.emit('leave-project', prevProjectIdRef.current)
     }
     socket.emit('join-project', currentProject.id)
+    setSocketRoom(currentProject.id)
     prevProjectIdRef.current = currentProject.id
 
     // Listen for features changes from other clients (only apply if NOT the editor)
@@ -643,11 +697,22 @@ export default function AppPage() {
   const saveTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
   const saveFeaturesToApi = useCallback(async () => {
     if (!currentProject?.id) return
+    const url = `/api/projects/${currentProject.id}/features`
+    const body = { features: featuresRef.current }
+
+    // If offline, queue the save for later sync
+    if (!navigator.onLine) {
+      addToSyncQueue(url, 'PUT', body)
+      setSyncQueueCount(getSyncQueue().length)
+      console.log('[Auto-Save] Offline — in Sync-Queue gespeichert')
+      return
+    }
+
     try {
-      const res = await fetch(`/api/projects/${currentProject.id}/features`, {
+      const res = await fetch(url, {
         method: 'PUT',
         headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify({ features: featuresRef.current }),
+        body: JSON.stringify(body),
       })
       if (res.ok) {
         console.log('[Auto-Save] Features gespeichert')
@@ -659,7 +724,10 @@ export default function AppPage() {
         console.warn('[Auto-Save] Projekt nicht in DB')
       }
     } catch (e) {
-      console.warn('[Auto-Save] Fehler:', e)
+      // Network error — queue for later
+      addToSyncQueue(url, 'PUT', body)
+      setSyncQueueCount(getSyncQueue().length)
+      console.warn('[Auto-Save] Netzwerkfehler — in Sync-Queue:', e)
     }
   }, [currentProject])
 
@@ -1389,6 +1457,17 @@ export default function AppPage() {
           onLogout={logout}
         />
 
+        {/* Offline banner */}
+        {isOffline && (
+          <div className="flex items-center justify-center gap-3 px-4 py-2 bg-orange-50 dark:bg-orange-950/40 border-b border-orange-200 dark:border-orange-800 text-sm text-orange-800 dark:text-orange-300">
+            <WifiOff className="w-4 h-4 shrink-0" />
+            <span>
+              <strong>Offline-Modus</strong> — Änderungen werden lokal gespeichert und beim Reconnect synchronisiert.
+              {syncQueueCount > 0 && ` (${syncQueueCount} ausstehend)`}
+            </span>
+          </div>
+        )}
+
         {/* Email verification banner */}
         {user && user.emailVerified === false && (
           <div className="flex items-center justify-center gap-3 px-4 py-2 bg-amber-50 dark:bg-amber-950/40 border-b border-amber-200 dark:border-amber-800 text-sm text-amber-800 dark:text-amber-300">

src/components/map/map-view.tsx

@@ -23,6 +23,19 @@ function formatDistance(meters: number): string {
   return `${(meters / 1000).toFixed(2)} km`
 }
 
+// Approximate polygon area in m² using the Shoelace formula on spherical coordinates
+function polygonArea(ring: number[][]): number {
+  const toRad = Math.PI / 180
+  const R = 6371000
+  let area = 0
+  const n = ring.length - 1 // exclude closing duplicate
+  for (let i = 0; i < n; i++) {
+    const j = (i + 1) % n
+    area += (ring[j][0] - ring[i][0]) * toRad * (2 + Math.sin(ring[i][1] * toRad) + Math.sin(ring[j][1] * toRad))
+  }
+  return Math.abs(area * R * R / 2)
+}
+
 // Point-to-segment distance in screen pixels (for click detection on lines)
 function pointToSegmentDist(px: number, py: number, x1: number, y1: number, x2: number, y2: number): number {
   const dx = x2 - x1, dy = y2 - y1
@@ -93,7 +106,7 @@ export function MapView({
   const measureMarkersRef = useRef<maplibregl.Marker[]>([])
   const measureCoordsRef = useRef<number[][]>([])
   const [isMapLoaded, setIsMapLoaded] = useState(false)
-  const [isSatellite, setIsSatellite] = useState(false)
+  const [activeBaseLayer, setActiveBaseLayer] = useState<'osm' | 'satellite' | 'swisstopo' | 'swissimage'>('osm')
   const [measurePointCount, setMeasurePointCount] = useState(0)
   const [measureFinished, setMeasureFinished] = useState(false)
   const [drawingPointCount, setDrawingPointCount] = useState(0)
@@ -676,6 +689,24 @@ export function MapView({
             attribution: '© Esri, Maxar, Earthstar Geographics',
             maxzoom: 19,
           },
+          'swisstopo': {
+            type: 'raster',
+            tiles: [
+              'https://wmts.geo.admin.ch/1.0.0/ch.swisstopo.pixelkarte-farbe/default/current/3857/{z}/{x}/{y}.jpeg',
+            ],
+            tileSize: 256,
+            attribution: '© swisstopo',
+            maxzoom: 18,
+          },
+          'swissimage': {
+            type: 'raster',
+            tiles: [
+              'https://wmts.geo.admin.ch/1.0.0/ch.swisstopo.swissimage/default/current/3857/{z}/{x}/{y}.jpeg',
+            ],
+            tileSize: 256,
+            attribution: '© swisstopo SWISSIMAGE',
+            maxzoom: 20,
+          },
         },
         layers: [
           {
@@ -689,6 +720,18 @@ export function MapView({
             source: 'satellite',
             layout: { visibility: 'none' },
           },
+          {
+            id: 'swisstopo',
+            type: 'raster',
+            source: 'swisstopo',
+            layout: { visibility: 'none' },
+          },
+          {
+            id: 'swissimage',
+            type: 'raster',
+            source: 'swissimage',
+            layout: { visibility: 'none' },
+          },
         ],
       },
       center: [initialCenter.lng, initialCenter.lat],
@@ -940,7 +983,7 @@ export function MapView({
         // Eraser mode: click on/near a feature to delete it
         if (mode === 'eraser') {
           const pixel = e.point
-          const tolerance = 10 // px
+          const tolerance = 20 // px
           const currentFeatures = featuresRef.current
           let closestIdx = -1
           let closestDist = Infinity
@@ -949,29 +992,44 @@ export function MapView({
             const f = currentFeatures[i]
             const geom = f.geometry
 
-            // Get all coordinates to check proximity
-            let allCoords: number[][] = []
             if (geom.type === 'Point') {
-              allCoords = [geom.coordinates as number[]]
-            } else if (geom.type === 'LineString') {
-              allCoords = geom.coordinates as number[][]
-            } else if (geom.type === 'Polygon') {
-              allCoords = (geom.coordinates as number[][][])[0] || []
-            }
-
-            for (const c of allCoords) {
-              const projected = m.project([c[0], c[1]])
+              const projected = m.project(geom.coordinates as [number, number])
               const dx = projected.x - pixel.x
               const dy = projected.y - pixel.y
               const dist = Math.sqrt(dx * dx + dy * dy)
-              if (dist < closestDist) {
-                closestDist = dist
-                closestIdx = i
+              if (dist < closestDist) { closestDist = dist; closestIdx = i }
+            } else if (geom.type === 'LineString') {
+              const lineCoords = geom.coordinates as number[][]
+              for (let j = 0; j < lineCoords.length - 1; j++) {
+                const p1 = m.project(lineCoords[j] as [number, number])
+                const p2 = m.project(lineCoords[j + 1] as [number, number])
+                const dist = pointToSegmentDist(pixel.x, pixel.y, p1.x, p1.y, p2.x, p2.y)
+                if (dist < closestDist) { closestDist = dist; closestIdx = i }
               }
+            } else if (geom.type === 'Polygon') {
+              const ring = (geom.coordinates as number[][][])[0] || []
+              // Check edges
+              for (let j = 0; j < ring.length - 1; j++) {
+                const p1 = m.project(ring[j] as [number, number])
+                const p2 = m.project(ring[j + 1] as [number, number])
+                const dist = pointToSegmentDist(pixel.x, pixel.y, p1.x, p1.y, p2.x, p2.y)
+                if (dist < closestDist) { closestDist = dist; closestIdx = i }
+              }
+              // Point-in-polygon test (screen space)
+              const projected = ring.map(c => m.project(c as [number, number]))
+              let inside = false
+              for (let j = 0, k = projected.length - 1; j < projected.length; k = j++) {
+                const xi = projected[j].x, yi = projected[j].y
+                const xk = projected[k].x, yk = projected[k].y
+                if (((yi > pixel.y) !== (yk > pixel.y)) && (pixel.x < (xk - xi) * (pixel.y - yi) / (yk - yi) + xi)) {
+                  inside = !inside
+                }
+              }
+              if (inside) { closestDist = 0; closestIdx = i }
             }
           }
 
-          if (closestIdx >= 0 && closestDist < tolerance * 3) {
+          if (closestIdx >= 0 && closestDist < tolerance) {
             const deleted = currentFeatures[closestIdx]
             const newFeatures = currentFeatures.filter((_, i) => i !== closestIdx)
             onFeaturesChangeRef.current(newFeatures)
@@ -1396,7 +1454,7 @@ export function MapView({
             pointer-events: none;
           `
 
-          const marker = new maplibregl.Marker({ element: arrowEl, anchor: 'center' })
+          const marker = new maplibregl.Marker({ element: arrowEl, anchor: 'center', rotationAlignment: 'viewport' })
             .setLngLat(p2 as [number, number])
             .addTo(map.current)
           markersRef.current.push(marker)
@@ -1468,7 +1526,21 @@ export function MapView({
           el.appendChild(labelLine)
           el.appendChild(infoLine)
         } else {
-          el.textContent = label
+          // Polygon: show label + area
+          const ring = (f.geometry.coordinates as number[][][])[0]
+          const area = polygonArea(ring)
+          const areaText = area < 10000 ? `${Math.round(area)} m²` : `${(area / 10000).toFixed(2)} ha`
+
+          const labelLine = document.createElement('div')
+          labelLine.textContent = label
+          labelLine.style.cssText = 'font-size:11px;font-weight:600;line-height:1.2;'
+
+          const infoLine = document.createElement('div')
+          infoLine.textContent = areaText
+          infoLine.style.cssText = 'font-size:8px;opacity:0.8;line-height:1.2;font-weight:400;'
+
+          el.appendChild(labelLine)
+          el.appendChild(infoLine)
         }
 
         // Double-click to edit label — only in select mode
@@ -1481,7 +1553,7 @@ export function MapView({
           })
         }
 
-        const marker = new maplibregl.Marker({ element: el, anchor: 'center' })
+        const marker = new maplibregl.Marker({ element: el, anchor: 'center', rotationAlignment: 'viewport' })
           .setLngLat(midpoint)
           .addTo(map.current)
         markersRef.current.push(marker)
@@ -1568,7 +1640,7 @@ export function MapView({
           }
 
           try {
-            const marker = new maplibregl.Marker({ element: wrapper, draggable: canEdit, anchor: 'center' })
+            const marker = new maplibregl.Marker({ element: wrapper, draggable: canEdit, anchor: 'center', rotationAlignment: 'viewport' })
               .setLngLat(coords)
               .addTo(map.current)
 
@@ -1634,7 +1706,7 @@ export function MapView({
           el.textContent = (f.properties.text as string) || ''
           wrapper.appendChild(el)
 
-          const marker = new maplibregl.Marker({ element: wrapper, draggable: canEdit, anchor: 'center' })
+          const marker = new maplibregl.Marker({ element: wrapper, draggable: canEdit, anchor: 'center', rotationAlignment: 'viewport' })
             .setLngLat(coords)
             .addTo(map.current)
 
@@ -2082,28 +2154,38 @@ export function MapView({
         </>
       )}
 
-      {/* Layer toggle: OSM / Satellite */}
+      {/* Layer toggle: cycle through base maps */}
       <button
         onClick={() => {
           if (!map.current) return
-          const newSat = !isSatellite
-          setIsSatellite(newSat)
-          map.current.setLayoutProperty('osm', 'visibility', newSat ? 'none' : 'visible')
-          map.current.setLayoutProperty('satellite', 'visibility', newSat ? 'visible' : 'none')
+          const layers: Array<'osm' | 'satellite' | 'swisstopo' | 'swissimage'> = ['osm', 'satellite', 'swisstopo', 'swissimage']
+          const currentIdx = layers.indexOf(activeBaseLayer)
+          const nextLayer = layers[(currentIdx + 1) % layers.length]
+          for (const l of layers) {
+            map.current.setLayoutProperty(l, 'visibility', l === nextLayer ? 'visible' : 'none')
+          }
+          setActiveBaseLayer(nextLayer)
         }}
         className="absolute top-3 right-3 z-10 flex items-center gap-1.5 px-2.5 py-1.5 rounded-lg text-xs font-semibold shadow-lg border transition-colors"
         style={{
-          background: isSatellite ? 'rgba(0,0,0,0.7)' : 'rgba(255,255,255,0.95)',
-          color: isSatellite ? '#fff' : '#333',
-          borderColor: isSatellite ? 'rgba(255,255,255,0.3)' : 'rgba(0,0,0,0.15)',
+          background: activeBaseLayer !== 'osm' ? 'rgba(0,0,0,0.7)' : 'rgba(255,255,255,0.95)',
+          color: activeBaseLayer !== 'osm' ? '#fff' : '#333',
+          borderColor: activeBaseLayer !== 'osm' ? 'rgba(255,255,255,0.3)' : 'rgba(0,0,0,0.15)',
         }}
-        title={isSatellite ? 'Zur Kartenansicht wechseln' : 'Zur Satellitenansicht wechseln'}
+        title="Kartenstil wechseln"
       >
-        {isSatellite ? (
-          <><svg className="w-4 h-4" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><path d="M3 7l6-3 6 3 6-3v13l-6 3-6-3-6 3z"/><path d="M9 4v13"/><path d="M15 7v13"/></svg>Karte</>
-        ) : (
+        {activeBaseLayer === 'osm' && (
           <><svg className="w-4 h-4" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><circle cx="12" cy="12" r="10"/><path d="M12 2a14.5 14.5 0 0 0 0 20 14.5 14.5 0 0 0 0-20"/><path d="M2 12h20"/></svg>Satellit</>
         )}
+        {activeBaseLayer === 'satellite' && (
+          <><svg className="w-4 h-4" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><path d="M3 7l6-3 6 3 6-3v13l-6 3-6-3-6 3z"/><path d="M9 4v13"/><path d="M15 7v13"/></svg>Swisstopo</>
+        )}
+        {activeBaseLayer === 'swisstopo' && (
+          <><svg className="w-4 h-4" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><circle cx="12" cy="12" r="10"/><path d="M12 2a14.5 14.5 0 0 0 0 20 14.5 14.5 0 0 0 0-20"/><path d="M2 12h20"/></svg>Luftbild CH</>
+        )}
+        {activeBaseLayer === 'swissimage' && (
+          <><svg className="w-4 h-4" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2"><path d="M3 7l6-3 6 3 6-3v13l-6 3-6-3-6 3z"/><path d="M9 4v13"/><path d="M15 7v13"/></svg>OSM</>
+        )}
       </button>
 
       {/* Zeichnung abschliessen Button (Linie/Polygon/Pfeil) */}

src/lib/offline-sync.ts

@@ -0,0 +1,97 @@
+// Offline detection and sync queue for saving changes when reconnecting
+
+const SYNC_QUEUE_KEY = 'lageplan-sync-queue'
+
+interface SyncQueueItem {
+  id: string
+  url: string
+  method: string
+  body: string
+  timestamp: number
+}
+
+/** Get all queued saves */
+export function getSyncQueue(): SyncQueueItem[] {
+  try {
+    const raw = localStorage.getItem(SYNC_QUEUE_KEY)
+    return raw ? JSON.parse(raw) : []
+  } catch {
+    return []
+  }
+}
+
+/** Add a save operation to the sync queue (called when offline) */
+export function addToSyncQueue(url: string, method: string, body: any): void {
+  const queue = getSyncQueue()
+  // Deduplicate: if same URL+method exists, replace it with newer data
+  const existing = queue.findIndex(q => q.url === url && q.method === method)
+  const item: SyncQueueItem = {
+    id: `${Date.now()}-${Math.random().toString(36).slice(2, 8)}`,
+    url,
+    method,
+    body: JSON.stringify(body),
+    timestamp: Date.now(),
+  }
+  if (existing >= 0) {
+    queue[existing] = item
+  } else {
+    queue.push(item)
+  }
+  localStorage.setItem(SYNC_QUEUE_KEY, JSON.stringify(queue))
+}
+
+/** Flush the sync queue — send all queued requests to the server */
+export async function flushSyncQueue(): Promise<{ success: number; failed: number }> {
+  const queue = getSyncQueue()
+  if (queue.length === 0) return { success: 0, failed: 0 }
+
+  let success = 0
+  let failed = 0
+  const remaining: SyncQueueItem[] = []
+
+  for (const item of queue) {
+    try {
+      const res = await fetch(item.url, {
+        method: item.method,
+        headers: { 'Content-Type': 'application/json' },
+        body: item.body,
+      })
+      if (res.ok) {
+        success++
+      } else {
+        // Server error — keep in queue for retry
+        remaining.push(item)
+        failed++
+      }
+    } catch {
+      // Still offline — keep in queue
+      remaining.push(item)
+      failed++
+    }
+  }
+
+  localStorage.setItem(SYNC_QUEUE_KEY, JSON.stringify(remaining))
+  return { success, failed }
+}
+
+/** Clear the sync queue */
+export function clearSyncQueue(): void {
+  localStorage.removeItem(SYNC_QUEUE_KEY)
+}
+
+/** Check if we're online */
+export function isOnline(): boolean {
+  return navigator.onLine
+}
+
+/** Register Background Sync (if supported) */
+export async function registerBackgroundSync(): Promise<void> {
+  if ('serviceWorker' in navigator && 'SyncManager' in window) {
+    try {
+      const reg = await navigator.serviceWorker.ready
+      await (reg as any).sync.register('sync-saves')
+    } catch {
+      // Background Sync not supported or failed — will use manual flush
+    }
+  }
+}

src/lib/socket.ts

@@ -3,23 +3,50 @@
 import { io, Socket } from 'socket.io-client'
 
 let socket: Socket | null = null
+let currentRoom: string | null = null
 
 export function getSocket(): Socket {
   if (!socket) {
     socket = io({
       path: '/socket.io',
-      transports: ['polling', 'websocket'],
+      transports: ['websocket', 'polling'],
       upgrade: true,
-      reconnectionAttempts: 10,
-      reconnectionDelay: 2000,
+      reconnection: true,
+      reconnectionAttempts: Infinity,
+      reconnectionDelay: 1000,
+      reconnectionDelayMax: 5000,
       timeout: 10000,
+      forceNew: false,
     })
     socket.on('connect', () => {
       console.log('[Socket.io] Connected:', socket?.id)
+      // Re-join project room after reconnect
+      if (currentRoom) {
+        console.log('[Socket.io] Re-joining room:', currentRoom)
+        socket?.emit('join-project', currentRoom)
+      }
+    })
+    socket.on('disconnect', (reason) => {
+      console.warn('[Socket.io] Disconnected:', reason)
+      if (reason === 'io server disconnect') {
+        // Server disconnected us, need to manually reconnect
+        socket?.connect()
+      }
     })
     socket.on('connect_error', (err) => {
       console.warn('[Socket.io] Connection error:', err.message)
     })
+    socket.io.on('reconnect', (attempt) => {
+      console.log('[Socket.io] Reconnected after', attempt, 'attempts')
+    })
+    socket.io.on('reconnect_attempt', (attempt) => {
+      console.log('[Socket.io] Reconnect attempt', attempt)
+    })
   }
   return socket
 }
+
+/** Track which room the socket should be in (for auto-rejoin on reconnect) */
+export function setSocketRoom(projectId: string | null): void {
+  currentRoom = projectId
+}