lib/data/services/export_service.dart

@@ -7,8 +7,6 @@ import 'package:pdf/pdf.dart' as pdf;
 import 'package:printing/printing.dart' as printing;
 import 'package:image/image.dart' as img;
 import '../../domain/models/model.dart';
-// math moved to utils in rot
-import '../../utils/rotation_utils.dart' as rot;
 
 // NOTE:
 // - This exporter uses a raster snapshot of the UI (RepaintBoundary) and embeds it into a new PDF.
@@ -17,6 +15,50 @@ import '../../utils/rotation_utils.dart' as rot;
 //   cannot import/modify existing PDF pages. If/when a suitable FOSS library exists, wire it here.
 
 class ExportService {
+  /// Compose a new PDF by rasterizing the original PDF pages (via pdfrx engine)
+  /// and optionally stamping a signature image on the specified page.
+  ///
+  /// Inputs:
+  /// - [inputPath]: Path to the original PDF to read
+  /// - [outputPath]: Path to write the composed PDF
+  /// - [uiPageSize]: The logical page size used by the UI layout (SignatureCardStateNotifier.pageSize)
+  /// - [signatureImageBytes]: PNG/JPEG bytes of the signature image to overlay
+  /// - [targetDpi]: Rasterization DPI for background pages
+  Future<bool> exportSignedPdfFromFile({
+    required String inputPath,
+    required String outputPath,
+    required Size uiPageSize,
+    required Uint8List? signatureImageBytes,
+    Map<int, List<SignaturePlacement>>? placementsByPage,
+    Map<String, Uint8List>? libraryBytes,
+    double targetDpi = 144.0,
+  }) async {
+    // Read source bytes and delegate to bytes-based exporter
+    Uint8List? srcBytes;
+    try {
+      srcBytes = await File(inputPath).readAsBytes();
+    } catch (_) {
+      srcBytes = null;
+    }
+    if (srcBytes == null) return false;
+    final bytes = await exportSignedPdfFromBytes(
+      srcBytes: srcBytes,
+      uiPageSize: uiPageSize,
+      signatureImageBytes: signatureImageBytes,
+      placementsByPage: placementsByPage,
+      libraryBytes: libraryBytes,
+      targetDpi: targetDpi,
+    );
+    if (bytes == null) return false;
+    try {
+      final file = File(outputPath);
+      await file.writeAsBytes(bytes, flush: true);
+      return true;
+    } catch (_) {
+      return false;
+    }
+  }
+
   /// Compose a new PDF from source PDF bytes; returns the resulting PDF bytes.
   Future<Uint8List?> exportSignedPdfFromBytes({
     required Uint8List srcBytes,
@@ -26,131 +68,6 @@ class ExportService {
     Map<String, Uint8List>? libraryBytes,
     double targetDpi = 144.0,
   }) async {
-    // Per-call caches to avoid redundant decode/encode and image embedding work
-    final Map<String, Uint8List> _processedBytesCache = <String, Uint8List>{};
-    final Map<String, pw.MemoryImage> _memoryImageCache =
-        <String, pw.MemoryImage>{};
-    final Map<String, double> _aspectRatioCache = <String, double>{};
-
-    // Returns a stable-ish cache key for bytes within this process (not content-hash, but good enough per-call)
-    String _baseKeyForBytes(Uint8List b) =>
-        '${identityHashCode(b)}:${b.length}';
-
-    // Fast PNG signature check (no string allocation)
-    bool _isPng(Uint8List bytes) {
-      if (bytes.length < 8) return false;
-      return bytes[0] == 0x89 &&
-          bytes[1] == 0x50 && // P
-          bytes[2] == 0x4E && // N
-          bytes[3] == 0x47 && // G
-          bytes[4] == 0x0D &&
-          bytes[5] == 0x0A &&
-          bytes[6] == 0x1A &&
-          bytes[7] == 0x0A;
-    }
-
-    // Resolve base (unprocessed) bytes for a placement, considering library override.
-    Uint8List _getBaseBytes(SignaturePlacement placement) {
-      Uint8List baseBytes = placement.asset.bytes;
-      final libKey = placement.asset.name;
-      if (libKey != null && libraryBytes != null) {
-        final libBytes = libraryBytes[libKey];
-        if (libBytes != null && libBytes.isNotEmpty) {
-          baseBytes = libBytes;
-        }
-      }
-      return baseBytes;
-    }
-
-    // Get processed bytes for a placement, with caching.
-    Uint8List _getProcessedBytes(SignaturePlacement placement) {
-      final Uint8List baseBytes = _getBaseBytes(placement);
-
-      final adj = placement.graphicAdjust;
-      final cacheKey =
-          '${_baseKeyForBytes(baseBytes)}|c=${adj.contrast}|b=${adj.brightness}|bg=${adj.bgRemoval}';
-      final cached = _processedBytesCache[cacheKey];
-      if (cached != null) return cached;
-
-      // If no graphic changes requested, return bytes as-is (conversion to PNG is deferred to MemoryImage step)
-      final bool needsAdjust =
-          (adj.contrast != 1.0 || adj.brightness != 1.0 || adj.bgRemoval);
-      if (!needsAdjust) {
-        _processedBytesCache[cacheKey] = baseBytes;
-        return baseBytes;
-      }
-
-      try {
-        final decoded = img.decodeImage(baseBytes);
-        if (decoded == null) {
-          _processedBytesCache[cacheKey] = baseBytes;
-          return baseBytes;
-        }
-        img.Image processed = decoded;
-
-        if (adj.contrast != 1.0 || adj.brightness != 1.0) {
-          processed = img.adjustColor(
-            processed,
-            contrast: adj.contrast,
-            brightness: adj.brightness,
-          );
-        }
-
-        if (adj.bgRemoval) {
-          processed = _removeBackground(processed);
-        }
-
-        final outBytes = Uint8List.fromList(img.encodePng(processed));
-        _processedBytesCache[cacheKey] = outBytes;
-        return outBytes;
-      } catch (_) {
-        // If processing fails, fall back to original
-        _processedBytesCache[cacheKey] = baseBytes;
-        return baseBytes;
-      }
-    }
-
-    // Wrap bytes in a pw.MemoryImage with caching, converting to PNG only when necessary.
-    pw.MemoryImage? _getMemoryImage(Uint8List bytes) {
-      final key = _baseKeyForBytes(bytes);
-      final cached = _memoryImageCache[key];
-      if (cached != null) return cached;
-      try {
-        if (_isPng(bytes)) {
-          final imgObj = pw.MemoryImage(bytes);
-          _memoryImageCache[key] = imgObj;
-          return imgObj;
-        }
-        // Convert to PNG to preserve transparency if not already PNG
-        final decoded = img.decodeImage(bytes);
-        if (decoded == null) return null;
-        final png = Uint8List.fromList(img.encodePng(decoded, level: 6));
-        final imgObj = pw.MemoryImage(png);
-        _memoryImageCache[key] = imgObj;
-        return imgObj;
-      } catch (_) {
-        return null;
-      }
-    }
-
-    // Compute and cache aspect ratio (width/height) for given bytes
-    double? _getAspectRatioFromBytes(Uint8List bytes) {
-      final key = _baseKeyForBytes(bytes);
-      final c = _aspectRatioCache[key];
-      if (c != null) return c;
-      try {
-        final decoded = img.decodeImage(bytes);
-        if (decoded == null || decoded.width <= 0 || decoded.height <= 0) {
-          return null;
-        }
-        final ar = decoded.width / decoded.height;
-        _aspectRatioCache[key] = ar;
-        return ar;
-      } catch (_) {
-        return null;
-      }
-    }
-
     final out = pw.Document(version: pdf.PdfVersion.pdf_1_4, compress: false);
     int pageIndex = 0;
     bool anyPage = false;
@@ -206,22 +123,51 @@ class ExportService {
                   final w = r.width * widthPts;
                   final h = r.height * heightPts;
 
-                  // Get processed bytes (cached) and then embed as MemoryImage (cached)
+                  // Process the signature asset with its graphic adjustments
-                  Uint8List bytes = _getProcessedBytes(placement);
+                  Uint8List bytes = placement.asset.bytes;
+                  if (bytes.isNotEmpty) {
+                    try {
+                      // Decode the image
+                      final decoded = img.decodeImage(bytes);
+                      if (decoded != null) {
+                        img.Image processed = decoded;
+
+                        // Apply contrast and brightness first
+                        if (placement.graphicAdjust.contrast != 1.0 ||
+                            placement.graphicAdjust.brightness != 0.0) {
+                          processed = img.adjustColor(
+                            processed,
+                            contrast: placement.graphicAdjust.contrast,
+                            brightness: placement.graphicAdjust.brightness,
+                          );
+                        }
+
+                        // Apply background removal after color adjustments
+                        if (placement.graphicAdjust.bgRemoval) {
+                          processed = _removeBackground(processed);
+                        }
+
+                        // Encode back to PNG to preserve transparency
+                        bytes = Uint8List.fromList(img.encodePng(processed));
+                      }
+                    } catch (e) {
+                      // If processing fails, use original bytes
+                    }
+                  }
+
+                  // Use fallback if no bytes available
                   if (bytes.isEmpty && signatureImageBytes != null) {
                     bytes = signatureImageBytes;
                   }
 
                   if (bytes.isNotEmpty) {
-                    final imgObj = _getMemoryImage(bytes);
+                    pw.MemoryImage? imgObj;
+                    try {
+                      imgObj = pw.MemoryImage(bytes);
+                    } catch (_) {
+                      imgObj = null;
+                    }
                     if (imgObj != null) {
-                      // Align with RotatedSignatureImage: counterclockwise positive
-                      final angle = rot.radians(placement.rotationDeg);
-                      // Prefer AR from base bytes to avoid extra decode of processed
-                      final baseBytes = _getBaseBytes(placement);
-                      final ar = _getAspectRatioFromBytes(baseBytes);
-                      final scaleToFit = rot.scaleToFitForAngle(angle, ar: ar);
-
                       children.add(
                         pw.Positioned(
                           left: left,
@@ -231,12 +177,12 @@ class ExportService {
                             height: h,
                             child: pw.FittedBox(
                               fit: pw.BoxFit.contain,
-                              child: pw.Transform.scale(
+                              child: pw.Transform.rotate(
-                                scale: scaleToFit,
+                                angle:
-                                child: pw.Transform.rotate(
+                                    placement.rotationDeg *
-                                  angle: angle,
+                                    3.1415926535 /
-                                  child: pw.Image(imgObj),
+                                    180.0,
-                                ),
+                                child: pw.Image(imgObj),
                               ),
                             ),
                           ),
@@ -281,7 +227,7 @@ class ExportService {
                 color: pdf.PdfColors.white,
               ),
             ];
-
+            // Multi-placement stamping on fallback page
             if (hasMulti && pagePlacements.isNotEmpty) {
               for (var i = 0; i < pagePlacements.length; i++) {
                 final placement = pagePlacements[i];
@@ -292,19 +238,65 @@ class ExportService {
                 final w = r.width * widthPts;
                 final h = r.height * heightPts;
 
-                Uint8List bytes = _getProcessedBytes(placement);
+                // Process the signature asset with its graphic adjustments
+                Uint8List bytes = placement.asset.bytes;
+                if (bytes.isNotEmpty) {
+                  try {
+                    // Decode the image
+                    final decoded = img.decodeImage(bytes);
+                    if (decoded != null) {
+                      img.Image processed = decoded;
+
+                      // Apply contrast and brightness first
+                      if (placement.graphicAdjust.contrast != 1.0 ||
+                          placement.graphicAdjust.brightness != 0.0) {
+                        processed = img.adjustColor(
+                          processed,
+                          contrast: placement.graphicAdjust.contrast,
+                          brightness: placement.graphicAdjust.brightness,
+                        );
+                      }
+
+                      // Apply background removal after color adjustments
+                      if (placement.graphicAdjust.bgRemoval) {
+                        processed = _removeBackground(processed);
+                      }
+
+                      // Encode back to PNG to preserve transparency
+                      bytes = Uint8List.fromList(img.encodePng(processed));
+                    }
+                  } catch (e) {
+                    // If processing fails, use original bytes
+                  }
+                }
+
+                // Use fallback if no bytes available
                 if (bytes.isEmpty && signatureImageBytes != null) {
                   bytes = signatureImageBytes;
                 }
 
                 if (bytes.isNotEmpty) {
-                  final imgObj = _getMemoryImage(bytes);
+                  pw.MemoryImage? imgObj;
+                  try {
+                    // Ensure PNG for transparency if not already
+                    final asStr = String.fromCharCodes(bytes.take(8));
+                    final isPng =
+                        bytes.length > 8 &&
+                        bytes[0] == 0x89 &&
+                        asStr.startsWith('\u0089PNG');
+                    if (isPng) {
+                      imgObj = pw.MemoryImage(bytes);
+                    } else {
+                      final decoded = img.decodeImage(bytes);
+                      if (decoded != null) {
+                        final png = img.encodePng(decoded, level: 6);
+                        imgObj = pw.MemoryImage(Uint8List.fromList(png));
+                      }
+                    }
+                  } catch (_) {
+                    imgObj = null;
+                  }
                   if (imgObj != null) {
-                    final angle = rot.radians(placement.rotationDeg);
-                    final baseBytes = _getBaseBytes(placement);
-                    final ar = _getAspectRatioFromBytes(baseBytes);
-                    final scaleToFit = rot.scaleToFitForAngle(angle, ar: ar);
-
                     children.add(
                       pw.Positioned(
                         left: left,
@@ -314,12 +306,10 @@ class ExportService {
                           height: h,
                           child: pw.FittedBox(
                             fit: pw.BoxFit.contain,
-                            child: pw.Transform.scale(
+                            child: pw.Transform.rotate(
-                              scale: scaleToFit,
+                              angle:
-                              child: pw.Transform.rotate(
+                                  placement.rotationDeg * 3.1415926535 / 180.0,
-                                angle: angle,
+                              child: pw.Image(imgObj),
-                                child: pw.Image(imgObj),
-                              ),
                             ),
                           ),
                         ),

lib/domain/models/signature_card.dart

@@ -18,7 +18,7 @@ class SignatureCard {
   });
 
   SignatureCard copyWith({
-    double? rotationDeg, //z axis is out of the screen, positive is CCW
+    double? rotationDeg,
     SignatureAsset? asset,
     GraphicAdjust? graphicAdjust,
   }) => SignatureCard(

lib/ui/features/pdf/widgets/draw_canvas.dart

@@ -54,8 +54,8 @@ class _DrawCanvasState extends State<DrawCanvas> {
                   onPressed: () async {
                     // Export signature to PNG bytes first
                     final byteData = await _control.toImage(
-                      width: 512,
+                      width: 1024,
-                      height: 256,
+                      height: 512,
                       fit: true,
                       color: Colors.black,
                       background: Colors.transparent,

lib/ui/features/pdf/widgets/pdf_page_area.dart

@@ -11,10 +11,21 @@ class PdfPageArea extends ConsumerStatefulWidget {
   const PdfPageArea({
     super.key,
     required this.pageSize,
+    required this.onDragSignature,
+    required this.onResizeSignature,
+    required this.onConfirmSignature,
+    required this.onClearActiveOverlay,
+    required this.onSelectPlaced,
     required this.controller,
   });
 
   final Size pageSize;
+  // viewerController removed in migration
+  final ValueChanged<Offset> onDragSignature;
+  final ValueChanged<Offset> onResizeSignature;
+  final VoidCallback onConfirmSignature;
+  final VoidCallback onClearActiveOverlay;
+  final ValueChanged<int?> onSelectPlaced;
   final PdfViewerController controller;
   @override
   ConsumerState<PdfPageArea> createState() => _PdfPageAreaState();
@@ -145,6 +156,11 @@ class _PdfPageAreaState extends ConsumerState<PdfPageArea> {
     if (isContinuous) {
       return PdfViewerWidget(
         pageSize: widget.pageSize,
+        onDragSignature: widget.onDragSignature,
+        onResizeSignature: widget.onResizeSignature,
+        onConfirmSignature: widget.onConfirmSignature,
+        onClearActiveOverlay: widget.onClearActiveOverlay,
+        onSelectPlaced: widget.onSelectPlaced,
         pageKeyBuilder: _pageKey,
         scrollToPage: _scrollToPage,
         controller: widget.controller,

lib/ui/features/pdf/widgets/pdf_screen.dart

@@ -109,6 +109,22 @@ class _PdfSignatureHomePageState extends ConsumerState<PdfSignatureHomePage> {
     return bytes;
   }
 
+  void _confirmSignature() {
+    // In simplified UI, confirmation is a no-op
+  }
+
+  void _onDragSignature(Offset delta) {
+    // In simplified UI, interactive overlay disabled
+  }
+
+  void _onResizeSignature(Offset delta) {
+    // In simplified UI, interactive overlay disabled
+  }
+
+  void _onSelectPlaced(int? index) {
+    // In simplified UI, selection is a no-op for tests
+  }
+
   Future<Uint8List?> _openDrawCanvas() async {
     final result = await showModalBottomSheet<Uint8List>(
       context: context,
@@ -307,6 +323,11 @@ class _PdfSignatureHomePageState extends ConsumerState<PdfSignatureHomePage> {
                 controller: _viewModel.controller,
                 key: const ValueKey('pdf_page_area'),
                 pageSize: _pageSize,
+                onDragSignature: _onDragSignature,
+                onResizeSignature: _onResizeSignature,
+                onConfirmSignature: _confirmSignature,
+                onClearActiveOverlay: () {},
+                onSelectPlaced: _onSelectPlaced,
               ),
             ),
       ),

lib/ui/features/pdf/widgets/pdf_viewer_widget.dart

@@ -10,12 +10,22 @@ class PdfViewerWidget extends ConsumerStatefulWidget {
   const PdfViewerWidget({
     super.key,
     required this.pageSize,
+    required this.onDragSignature,
+    required this.onResizeSignature,
+    required this.onConfirmSignature,
+    required this.onClearActiveOverlay,
+    required this.onSelectPlaced,
     this.pageKeyBuilder,
     this.scrollToPage,
     required this.controller,
   });
 
   final Size pageSize;
+  final ValueChanged<Offset> onDragSignature;
+  final ValueChanged<Offset> onResizeSignature;
+  final VoidCallback onConfirmSignature;
+  final VoidCallback onClearActiveOverlay;
+  final ValueChanged<int?> onSelectPlaced;
   final GlobalKey Function(int page)? pageKeyBuilder;
   final void Function(int page)? scrollToPage;
   final PdfViewerController controller;
@@ -78,6 +88,11 @@ class _PdfViewerWidgetState extends ConsumerState<PdfViewerWidget> {
             widget.pageKeyBuilder ??
             (page) => GlobalKey(debugLabel: 'page_$page'),
         scrollToPage: widget.scrollToPage ?? (page) {},
+        onDragSignature: widget.onDragSignature,
+        onResizeSignature: widget.onResizeSignature,
+        onConfirmSignature: widget.onConfirmSignature,
+        onClearActiveOverlay: widget.onClearActiveOverlay,
+        onSelectPlaced: widget.onSelectPlaced,
       );
     }
 
@@ -148,6 +163,11 @@ class _PdfViewerWidgetState extends ConsumerState<PdfViewerWidget> {
             PdfPageOverlays(
               pageSize: Size(pageRect.width, pageRect.height),
               pageNumber: page.pageNumber,
+              onDragSignature: widget.onDragSignature,
+              onResizeSignature: widget.onResizeSignature,
+              onConfirmSignature: widget.onConfirmSignature,
+              onClearActiveOverlay: widget.onClearActiveOverlay,
+              onSelectPlaced: widget.onSelectPlaced,
             ),
           ];
         },

lib/ui/features/signature/widgets/image_editor_dialog.dart

@@ -41,7 +41,7 @@ class _ImageEditorDialogState extends State<ImageEditorDialog> {
   late bool _bgRemoval;
   late double _contrast;
   late double _brightness;
-  late final ValueNotifier<double> _rotation;
+  late double _rotation;
 
   // Cached image data
   late Uint8List _originalBytes; // Original asset bytes (never mutated)
@@ -59,7 +59,7 @@ class _ImageEditorDialogState extends State<ImageEditorDialog> {
     _bgRemoval = widget.initialGraphicAdjust.bgRemoval;
     _contrast = widget.initialGraphicAdjust.contrast;
     _brightness = widget.initialGraphicAdjust.brightness;
-    _rotation = ValueNotifier<double>(widget.initialRotation);
+    _rotation = widget.initialRotation;
     _originalBytes = widget.asset.bytes;
     // Decode lazily only if/when background removal is needed
     if (_bgRemoval) {
@@ -172,7 +172,6 @@ class _ImageEditorDialogState extends State<ImageEditorDialog> {
 
   @override
   void dispose() {
-    _rotation.dispose();
     _bgRemovalDebounce?.cancel();
     super.dispose();
   }
@@ -207,20 +206,19 @@ class _ImageEditorDialogState extends State<ImageEditorDialog> {
                     ),
                     child: ClipRRect(
                       borderRadius: BorderRadius.circular(8),
-                      child: ValueListenableBuilder<double>(
+                      child:
-                        valueListenable: _rotation,
+                          _bgRemoval
-                        builder: (context, rot, child) {
+                              ? RotatedSignatureImage(
-                          final image = RotatedSignatureImage(
+                                bytes: _displayBytes,
-                            bytes: _displayBytes,
+                                rotationDeg: _rotation,
-                            rotationDeg: rot,
+                              )
-                          );
+                              : ColorFiltered(
-                          if (_bgRemoval) return image;
+                                colorFilter: _currentColorFilter(),
-                          return ColorFiltered(
+                                child: RotatedSignatureImage(
-                            colorFilter: _currentColorFilter(),
+                                  bytes: _displayBytes,
-                            child: image,
+                                  rotationDeg: _rotation,
-                          );
+                                ),
-                        },
+                              ),
-                      ),
                     ),
                   ),
                 ),
@@ -250,26 +248,16 @@ class _ImageEditorDialogState extends State<ImageEditorDialog> {
                   children: [
                     Text(l10n.rotate),
                     Expanded(
-                      child: ValueListenableBuilder<double>(
+                      child: Slider(
-                        valueListenable: _rotation,
+                        key: const Key('sld_rotation'),
-                        builder: (context, rot, _) {
+                        min: -180,
-                          return Slider(
+                        max: 180,
-                            key: const Key('sld_rotation'),
+                        divisions: 72,
-                            min: -180,
+                        value: _rotation,
-                            max: 180,
+                        onChanged: (v) => setState(() => _rotation = v),
-                            divisions: 72,
-                            value: rot,
-                            onChanged: (v) => _rotation.value = v,
-                          );
-                        },
                       ),
                     ),
-                    ValueListenableBuilder<double>(
+                    Text('${_rotation.toStringAsFixed(0)}°'),
-                      valueListenable: _rotation,
-                      builder:
-                          (context, rot, _) =>
-                              Text('${rot.toStringAsFixed(0)}°'),
-                    ),
                   ],
                 ),
                 const SizedBox(height: 12),
@@ -281,7 +269,7 @@ class _ImageEditorDialogState extends State<ImageEditorDialog> {
                       onPressed:
                           () => Navigator.of(context).pop(
                             ImageEditorResult(
-                              rotation: _rotation.value,
+                              rotation: _rotation,
                               graphicAdjust: domain.GraphicAdjust(
                                 contrast: _contrast,
                                 brightness: _brightness,

lib/ui/features/signature/widgets/rotated_signature_image.dart

@@ -1,19 +1,17 @@
+import 'dart:math' as math;
 import 'dart:typed_data';
 import 'package:flutter/material.dart';
-import '../../../../utils/rotation_utils.dart' as rot;
+import 'package:image/image.dart' as img;
 
 /// A lightweight widget to render signature bytes with rotation and an
 /// angle-aware scale-to-fit so the rotated image stays within its bounds.
-/// Aware that `decodeImage` large images can be crazily slow, especially on web.
 class RotatedSignatureImage extends StatefulWidget {
   const RotatedSignatureImage({
     super.key,
     required this.bytes,
-    this.rotationDeg = 0.0, // counterclockwise as positive
+    this.rotationDeg = 0.0,
     this.filterQuality = FilterQuality.low,
     this.semanticLabel,
-    this.cacheWidth,
-    this.cacheHeight,
   });
 
   final Uint8List bytes;
@@ -24,10 +22,6 @@ class RotatedSignatureImage extends StatefulWidget {
   final Alignment alignment = Alignment.center;
   final bool wrapInRepaintBoundary = true;
   final String? semanticLabel;
-  // Hint the decoder to decode at a smaller size to reduce memory/latency.
-  // On some platforms these may be ignored, but they are safe no-ops.
-  final int? cacheWidth;
-  final int? cacheHeight;
 
   @override
   State<RotatedSignatureImage> createState() => _RotatedSignatureImageState();
@@ -51,9 +45,8 @@ class _RotatedSignatureImageState extends State<RotatedSignatureImage> {
   @override
   void didUpdateWidget(covariant RotatedSignatureImage oldWidget) {
     super.didUpdateWidget(oldWidget);
-    // Only re-resolve when the bytes change. Rotation does not affect
+    if (!identical(oldWidget.bytes, widget.bytes) ||
-    // intrinsic aspect ratio, so avoid expensive decode/resolve on slider drags.
+        oldWidget.rotationDeg != widget.rotationDeg) {
-    if (!identical(oldWidget.bytes, widget.bytes)) {
       _derivedAspectRatio = null;
       _resolveImage();
     }
@@ -67,12 +60,25 @@ class _RotatedSignatureImageState extends State<RotatedSignatureImage> {
 
   void _resolveImage() {
     _unlisten();
-    // Resolve via ImageProvider; when first frame arrives, capture intrinsic size.
+    // Decode synchronously to get aspect ratio
-    // Avoid synchronous decode on UI thread to keep rotation smooth.
+    // Guard against empty / invalid bytes that some simplified tests may inject.
     if (widget.bytes.isEmpty) {
-      _setAspectRatio(1.0); // safe fallback
+      _setAspectRatio(1.0); // assume square to avoid layout exceptions
       return;
     }
+    try {
+      final decoded = img.decodePng(widget.bytes);
+      if (decoded != null) {
+        final w = decoded.width;
+        final h = decoded.height;
+        if (w > 0 && h > 0) {
+          _setAspectRatio(w / h);
+        }
+      }
+    } catch (_) {
+      // Swallow decode errors for test-provided dummy data; assume square.
+      _setAspectRatio(1.0);
+    }
     final stream = _provider.resolve(createLocalImageConfiguration(context));
     _stream = stream;
     _listener = ImageStreamListener((ImageInfo info, bool sync) {
@@ -101,7 +107,7 @@ class _RotatedSignatureImageState extends State<RotatedSignatureImage> {
 
   @override
   Widget build(BuildContext context) {
-    final angle = rot.ccwRadians(widget.rotationDeg);
+    final angle = widget.rotationDeg * math.pi / 180.0;
     Widget img = Image.memory(
       widget.bytes,
       fit: widget.fit,
@@ -109,10 +115,6 @@ class _RotatedSignatureImageState extends State<RotatedSignatureImage> {
       filterQuality: widget.filterQuality,
       alignment: widget.alignment,
       semanticLabel: widget.semanticLabel,
-      // Provide at most one dimension to preserve aspect ratio if only one is set
-      cacheWidth: widget.cacheWidth,
-      cacheHeight: widget.cacheHeight,
-      isAntiAlias: false,
       errorBuilder: (context, error, stackTrace) {
         // Return a placeholder for invalid images
         return Container(
@@ -123,7 +125,16 @@ class _RotatedSignatureImageState extends State<RotatedSignatureImage> {
     );
 
     if (angle != 0.0) {
-      final scaleToFit = rot.scaleToFitForAngle(angle, ar: _derivedAspectRatio);
+      final double c = math.cos(angle).abs();
+      final double s = math.sin(angle).abs();
+      final ar = _derivedAspectRatio;
+      double scaleToFit;
+      if (ar != null && ar > 0) {
+        scaleToFit = math.min(ar / (ar * c + s), 1.0 / (ar * s + c));
+      } else {
+        // Fallback: square approximation
+        scaleToFit = 1.0 / (c + s).clamp(1.0, double.infinity);
+      }
       img = Transform.scale(
         scale: scaleToFit,
         child: Transform.rotate(angle: angle, child: img),

lib/ui/features/signature/widgets/signature_card.dart

@@ -1,4 +1,3 @@
-import 'dart:typed_data';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:pdf_signature/domain/models/model.dart' as domain;
@@ -8,14 +7,15 @@ import 'package:pdf_signature/l10n/app_localizations.dart';
 import '../view_model/signature_view_model.dart';
 import '../view_model/dragging_signature_view_model.dart';
 
-class SignatureCardView extends ConsumerStatefulWidget {
+class SignatureCard extends ConsumerWidget {
-  const SignatureCardView({
+  const SignatureCard({
     super.key,
     required this.asset,
     required this.disabled,
     required this.onDelete,
     this.onTap,
     this.onAdjust,
+    this.useCurrentBytesForDrag = false,
     this.rotationDeg = 0.0,
     this.graphicAdjust = const domain.GraphicAdjust(),
   });
@@ -24,14 +24,9 @@ class SignatureCardView extends ConsumerStatefulWidget {
   final VoidCallback onDelete;
   final VoidCallback? onTap;
   final VoidCallback? onAdjust;
+  final bool useCurrentBytesForDrag;
   final double rotationDeg;
   final domain.GraphicAdjust graphicAdjust;
-  @override
-  ConsumerState<SignatureCardView> createState() => _SignatureCardViewState();
-}
-
-class _SignatureCardViewState extends ConsumerState<SignatureCardView> {
-  Uint8List? _lastBytesRef;
   Future<void> _showContextMenu(BuildContext context, Offset position) async {
     final selected = await showMenu<String>(
       context: context,
@@ -55,40 +50,22 @@ class _SignatureCardViewState extends ConsumerState<SignatureCardView> {
       ],
     );
     if (selected == 'adjust') {
-      widget.onAdjust?.call();
+      onAdjust?.call();
     } else if (selected == 'delete') {
-      widget.onDelete();
+      onDelete();
     }
   }
 
-  void _maybePrecache(Uint8List bytes) {
-    if (identical(_lastBytesRef, bytes)) return;
-    _lastBytesRef = bytes;
-    // Schedule after frame to avoid doing work during build.
-    WidgetsBinding.instance.addPostFrameCallback((_) {
-      // Use single-dimension hints to preserve aspect ratio.
-      final img128 = ResizeImage(MemoryImage(bytes), height: 128);
-      final img256 = ResizeImage(MemoryImage(bytes), height: 256);
-      precacheImage(img128, context);
-      precacheImage(img256, context);
-    });
-  }
-
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context, WidgetRef ref) {
     final displayData = ref
         .watch(signatureViewModelProvider)
-        .getDisplaySignatureData(widget.asset, widget.graphicAdjust);
+        .getDisplaySignatureData(asset, graphicAdjust);
-    _maybePrecache(displayData.bytes);
     // Fit inside 96x64 with 6px padding using the shared rotated image widget
     const boxW = 96.0, boxH = 64.0, pad = 6.0;
-    // Hint decoder with small target size to reduce decode cost.
-    // The card shows inside 96x64 with 6px padding; request ~128px max.
     Widget coreImage = RotatedSignatureImage(
       bytes: displayData.bytes,
-      rotationDeg: widget.rotationDeg,
+      rotationDeg: rotationDeg,
-      // Only set one dimension to keep aspect ratio
-      cacheHeight: 128,
     );
     Widget img =
         (displayData.colorMatrix != null)
@@ -125,7 +102,7 @@ class _SignatureCardViewState extends ConsumerState<SignatureCardView> {
               top: 0,
               child: IconButton(
                 icon: const Icon(Icons.close, size: 16),
-                onPressed: widget.disabled ? null : widget.onDelete,
+                onPressed: disabled ? null : onDelete,
                 tooltip: 'Remove',
                 padding: const EdgeInsets.all(2),
               ),
@@ -134,31 +111,33 @@ class _SignatureCardViewState extends ConsumerState<SignatureCardView> {
         ),
       ),
     );
-    Widget child =
+    Widget child = onTap != null ? InkWell(onTap: onTap, child: base) : base;
-        widget.onTap != null ? InkWell(onTap: widget.onTap, child: base) : base;
     // Add context menu for adjust/delete on right-click or long-press
     child = GestureDetector(
       key: const Key('gd_signature_card_area'),
       behavior: HitTestBehavior.opaque,
       onSecondaryTapDown:
-          widget.disabled
+          disabled
               ? null
               : (details) => _showContextMenu(context, details.globalPosition),
       onLongPressStart:
-          widget.disabled
+          disabled
               ? null
               : (details) => _showContextMenu(context, details.globalPosition),
       child: child,
     );
-    if (widget.disabled) return child;
+    if (disabled) return child;
     return Draggable<SignatureDragData>(
-      data: SignatureDragData(
+      data:
-        card: domain.SignatureCard(
+          useCurrentBytesForDrag
-          asset: widget.asset,
+              ? const SignatureDragData()
-          rotationDeg: widget.rotationDeg,
+              : SignatureDragData(
-          graphicAdjust: widget.graphicAdjust,
+                card: domain.SignatureCard(
-        ),
+                  asset: asset,
-      ),
+                  rotationDeg: rotationDeg,
+                  graphicAdjust: graphicAdjust,
+                ),
+              ),
       onDragStarted: () {
         ref.read(isDraggingSignatureViewModelProvider.notifier).state = true;
       },
@@ -187,14 +166,12 @@ class _SignatureCardViewState extends ConsumerState<SignatureCardView> {
                         ),
                         child: RotatedSignatureImage(
                           bytes: displayData.bytes,
-                          rotationDeg: widget.rotationDeg,
+                          rotationDeg: rotationDeg,
-                          cacheHeight: 256,
                         ),
                       )
                       : RotatedSignatureImage(
                         bytes: displayData.bytes,
-                        rotationDeg: widget.rotationDeg,
+                        rotationDeg: rotationDeg,
-                        cacheHeight: 256,
                       ),
             ),
           ),

lib/ui/features/signature/widgets/signature_drag_data.dart

@@ -1,6 +1,6 @@
 import 'package:pdf_signature/domain/models/model.dart';
 
 class SignatureDragData {
-  final SignatureCard card; // null means use current processed signature
+  final SignatureCard? card; // null means use current processed signature
-  const SignatureDragData({required this.card});
+  const SignatureDragData({this.card});
 }

lib/ui/features/signature/widgets/signature_drawer.dart

@@ -6,9 +6,9 @@ import 'package:pdf_signature/l10n/app_localizations.dart';
 
 import 'package:pdf_signature/data/repositories/signature_asset_repository.dart';
 import 'package:pdf_signature/data/repositories/signature_card_repository.dart';
-import 'package:pdf_signature/domain/models/signature_asset.dart';
+import 'package:pdf_signature/domain/models/model.dart' hide SignatureCard;
 import 'image_editor_dialog.dart';
-import 'signature_card_view.dart';
+import 'signature_card.dart';
 import '../../pdf/view_model/pdf_view_model.dart';
 
 /// Data for drag-and-drop is in signature_drag_data.dart
@@ -49,7 +49,7 @@ class _SignatureDrawerState extends ConsumerState<SignatureDrawer> {
               margin: EdgeInsets.zero,
               child: Padding(
                 padding: const EdgeInsets.all(12),
-                child: SignatureCardView(
+                child: SignatureCard(
                   key: ValueKey('sig_card_${library.indexOf(card)}'),
                   asset: card.asset,
                   rotationDeg: card.rotationDeg,

lib/utils/rotation_utils.dart

@@ -1,21 +0,0 @@
-import 'dart:math' as math;
-
-/// Convert degrees to radians with counterclockwise as positive in screen space
-/// by inverting the sign (because screen Y axis points downwards).
-double ccwRadians(double degrees) => -degrees * math.pi / 180.0;
-
-/// Classic math convention: positive degrees rotate counterclockwise.
-/// No screen-space Y-inversion applied.
-double radians(double degrees) => degrees * math.pi / 180.0;
-
-/// Compute scale factor to keep a rotated rectangle of aspect ratio [ar]
-/// within a unit 1x1 box. If [ar] is null or <= 0, fall back to a square.
-/// Returns the scale to apply before rotation.
-double scaleToFitForAngle(double angleRad, {double? ar}) {
-  final double c = angleRad == 0.0 ? 1.0 : math.cos(angleRad).abs();
-  final double s = angleRad == 0.0 ? 0.0 : math.sin(angleRad).abs();
-  if (ar != null && ar > 0) {
-    return math.min(ar / (ar * c + s), 1.0 / (ar * s + c));
-  }
-  return 1.0 / (c + s).clamp(1.0, double.infinity);
-}

test/widget/pdf_page_area_early_jump_test.dart

@@ -42,6 +42,11 @@ void main() {
                 height: 520,
                 child: PdfPageArea(
                   pageSize: Size(676, 400),
+                  onDragSignature: _noopOffset,
+                  onResizeSignature: _noopOffset,
+                  onConfirmSignature: _noop,
+                  onClearActiveOverlay: _noop,
+                  onSelectPlaced: _noopInt,
                   controller: PdfViewerController(),
                 ),
               ),
@@ -70,4 +75,6 @@ void main() {
   });
 }
 
-// No extra callbacks required in the new API
+void _noop() {}
+void _noopInt(int? _) {}
+void _noopOffset(Offset _) {}

test/widget/pdf_page_area_jump_test.dart

@@ -43,6 +43,11 @@ void main() {
                   height: 520,
                   child: PdfPageArea(
                     pageSize: Size(676, 400),
+                    onDragSignature: _noopOffset,
+                    onResizeSignature: _noopOffset,
+                    onConfirmSignature: _noop,
+                    onClearActiveOverlay: _noop,
+                    onSelectPlaced: _noopInt,
                     controller: PdfViewerController(),
                   ),
                 ),
@@ -101,4 +106,6 @@ void main() {
   );
 }
 
-// No extra callbacks required in the new API
+void _noop() {}
+void _noopInt(int? _) {}
+void _noopOffset(Offset _) {}

test/widget/pdf_page_area_test.dart

@@ -43,6 +43,11 @@ void main() {
                 height: 520,
                 child: PdfPageArea(
                   pageSize: const Size(676, 400),
+                  onDragSignature: _noopOffset,
+                  onResizeSignature: _noopOffset,
+                  onConfirmSignature: _noop,
+                  onClearActiveOverlay: _noop,
+                  onSelectPlaced: _noopInt,
                   controller: PdfViewerController(),
                 ),
               ),
@@ -86,6 +91,11 @@ void main() {
                 // Keep aspect ratio consistent with uiPageSize
                 child: PdfPageArea(
                   pageSize: uiPageSize,
+                  onDragSignature: _noopOffset,
+                  onResizeSignature: _noopOffset,
+                  onConfirmSignature: _noop,
+                  onClearActiveOverlay: _noop,
+                  onSelectPlaced: _noopInt,
                   controller: PdfViewerController(),
                 ),
               ),
@@ -160,4 +170,6 @@ void main() {
   });
 }
 
-// No extra callbacks required in the new API
+void _noop() {}
+void _noopInt(int? _) {}
+void _noopOffset(Offset _) {}