Add NextSnap PWA with photo gallery viewer and continuous capture

Offline-first photo capture app for Nextcloud with:
- Camera capture with continuous mode (auto-reopens after each photo)
- File browser with fullscreen image gallery, swipe navigation, and rename
- Upload queue with background sync engine
- Admin panel for Nextcloud user management
- Service worker for offline-first caching (v13)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/routes/webdav_proxy.py

@@ -0,0 +1,186 @@
+from flask import Blueprint, request, jsonify, send_file
+from app.services.auth import require_auth, get_current_user
+from app.services.nextcloud import NextcloudClient
+from config import Config
+from io import BytesIO
+from PIL import Image
+
+bp = Blueprint('webdav', __name__, url_prefix='/api/files')
+
+def _get_nc_client():
+    """Get Nextcloud client for current user."""
+    user = get_current_user()
+    if not user:
+        return None
+    return NextcloudClient(Config.NEXTCLOUD_URL, user['username'], user['password'])
+
+@bp.route('/list', methods=['GET'])
+@require_auth
+def list_files():
+    """List files and directories at the given path."""
+    path = request.args.get('path', '/')
+    
+    nc_client = _get_nc_client()
+    if not nc_client:
+        return jsonify({'error': 'Not authenticated'}), 401
+    
+    try:
+        result = nc_client.propfind(path, depth=1)
+        return jsonify(result), 200
+    except Exception as e:
+        return jsonify({'error': f'Failed to list files: {str(e)}'}), 500
+
+@bp.route('/upload', methods=['PUT', 'POST'])
+@require_auth
+def upload_file():
+    """Upload a file to Nextcloud."""
+    nc_client = _get_nc_client()
+    if not nc_client:
+        return jsonify({'error': 'Not authenticated'}), 401
+    
+    # Get target path from query parameter or form data
+    target_path = request.args.get('path') or request.form.get('path')
+    if not target_path:
+        return jsonify({'error': 'Target path is required'}), 400
+    
+    # Get file data
+    if 'file' in request.files:
+        # Multipart upload
+        file = request.files['file']
+        file_data = file.read()
+        filename = file.filename
+    else:
+        # Raw binary upload
+        file_data = request.get_data()
+        filename = request.args.get('filename', 'upload.jpg')
+    
+    if not file_data:
+        return jsonify({'error': 'No file data provided'}), 400
+    
+    # Construct full path
+    full_path = f"{target_path.rstrip('/')}/{filename}"
+    
+    try:
+        result = nc_client.put_file(full_path, file_data)
+        return jsonify({
+            'success': True,
+            'path': full_path,
+            'url': result.get('url', '')
+        }), 200
+    except Exception as e:
+        return jsonify({'error': f'Upload failed: {str(e)}'}), 500
+
+@bp.route('/verify', methods=['HEAD', 'GET'])
+@require_auth
+def verify_file():
+    """Verify that a file exists on Nextcloud."""
+    path = request.args.get('path')
+    if not path:
+        return jsonify({'error': 'Path is required'}), 400
+    
+    nc_client = _get_nc_client()
+    if not nc_client:
+        return jsonify({'error': 'Not authenticated'}), 401
+    
+    try:
+        exists = nc_client.head(path)
+        if exists:
+            return jsonify({'exists': True}), 200
+        else:
+            return jsonify({'exists': False}), 404
+    except Exception as e:
+        return jsonify({'error': f'Verification failed: {str(e)}'}), 500
+
+@bp.route('/mkdir', methods=['POST'])
+@require_auth
+def make_directory():
+    """Create a new directory on Nextcloud."""
+    data = request.get_json()
+    if not data or 'path' not in data:
+        return jsonify({'error': 'Path is required'}), 400
+    
+    path = data['path']
+    
+    nc_client = _get_nc_client()
+    if not nc_client:
+        return jsonify({'error': 'Not authenticated'}), 401
+    
+    try:
+        nc_client.mkcol(path)
+        return jsonify({'success': True, 'path': path}), 201
+    except Exception as e:
+        return jsonify({'error': f'Failed to create directory: {str(e)}'}), 500
+
+@bp.route('/rename', methods=['POST'])
+@require_auth
+def rename_file():
+    """Rename or move a file on Nextcloud."""
+    data = request.get_json()
+    if not data or 'source' not in data or 'destination' not in data:
+        return jsonify({'error': 'Source and destination paths are required'}), 400
+    
+    source = data['source']
+    destination = data['destination']
+    
+    nc_client = _get_nc_client()
+    if not nc_client:
+        return jsonify({'error': 'Not authenticated'}), 401
+    
+    try:
+        nc_client.move(source, destination)
+        return jsonify({
+            'success': True,
+            'source': source,
+            'destination': destination
+        }), 200
+    except Exception as e:
+        return jsonify({'error': f'Failed to rename file: {str(e)}'}), 500
+
+@bp.route('/thumbnail', methods=['GET'])
+@require_auth
+def get_thumbnail():
+    """Generate and return a thumbnail of an image file."""
+    path = request.args.get('path')
+    size = request.args.get('size', '256')
+    
+    if not path:
+        return jsonify({'error': 'Path is required'}), 400
+    
+    try:
+        size = int(size)
+        if size < 32 or size > 1024:
+            size = 256
+    except ValueError:
+        size = 256
+    
+    nc_client = _get_nc_client()
+    if not nc_client:
+        return jsonify({'error': 'Not authenticated'}), 401
+    
+    try:
+        # Download the file from Nextcloud
+        file_data = nc_client.get_file(path)
+        
+        # Open image and create thumbnail
+        image = Image.open(BytesIO(file_data))
+        
+        # Convert to RGB if necessary (for PNG with transparency, etc.)
+        if image.mode not in ('RGB', 'L'):
+            image = image.convert('RGB')
+        
+        # Create thumbnail maintaining aspect ratio
+        image.thumbnail((size, size), Image.Resampling.LANCZOS)
+        
+        # Save to BytesIO
+        output = BytesIO()
+        image.save(output, format='JPEG', quality=85)
+        output.seek(0)
+        
+        return send_file(
+            output,
+            mimetype='image/jpeg',
+            as_attachment=False,
+            download_name=f'thumbnail_{size}.jpg'
+        )
+    except Exception as e:
+        return jsonify({'error': f'Failed to generate thumbnail: {str(e)}'}), 500