feat: horizontal flip with R key, baked into crop save (v1.6.0)

- R mirrors the view about the viewport centre and clears the active effects
  (same reset as double right click); pressing R again restores the original
  orientation. Pan/zoom are kept.
- Image switch, fill/fit toggle and right double click also clear the flip.
- Crop save (Ctrl+S) mirrors the output too, so the saved JPEG matches the
  on-screen view (verified in combination with rotation).
- Shortcut lists (tr/en), README and CHANGELOG updated; deb rebuilt as 1.6.0.

lib/l10n/app_en.arb

@@ -6,7 +6,7 @@
   "sortByName": "By name",
   "appDescription": "Ultra-lightweight and fast image viewer. Open images and use arrows or keyboard keys to navigate.",
   "shortcuts": "Shortcuts",
-  "shortcutsList": "• Left/Right arrow — previous/next image\n• Ctrl+S — save visible area (JPEG 93)\n• Ctrl+Q — close window\n• Ctrl+Shift+Q — close all windows\n• Double click — toggle fill/fit\n• Right-drag — contrast\n• Shift+right-drag — rotate\n• Ctrl+right-drag — saturation\n• Ctrl+Shift+right-drag — brightness",
+  "shortcutsList": "• Left/Right arrow — previous/next image\n• Ctrl+S — save visible area (JPEG 93)\n• Ctrl+Q — close window\n• Ctrl+Shift+Q — close all windows\n• Double click — toggle fill/fit\n• Right-drag — contrast\n• Shift+right-drag — rotate\n• Ctrl+right-drag — saturation\n• Ctrl+Shift+right-drag — brightness\n• R — flip horizontally (resets effects, press again to undo)",
   "print": "Print",
   "close": "Close",
   "saveCrop": "Save visible area (JPEG 93)",

lib/l10n/app_localizations.dart

@@ -137,7 +137,7 @@ abstract class AppLocalizations {
   /// No description provided for @shortcutsList.
   ///
   /// In en, this message translates to:
-  /// **'• Left/Right arrow — previous/next image\n• Ctrl+S — save visible area (JPEG 93)\n• Ctrl+Q — close window\n• Ctrl+Shift+Q — close all windows\n• Double click — toggle fill/fit\n• Right-drag — contrast\n• Shift+right-drag — rotate\n• Ctrl+right-drag — saturation\n• Ctrl+Shift+right-drag — brightness'**
+  /// **'• Left/Right arrow — previous/next image\n• Ctrl+S — save visible area (JPEG 93)\n• Ctrl+Q — close window\n• Ctrl+Shift+Q — close all windows\n• Double click — toggle fill/fit\n• Right-drag — contrast\n• Shift+right-drag — rotate\n• Ctrl+right-drag — saturation\n• Ctrl+Shift+right-drag — brightness\n• R — flip horizontally (resets effects, press again to undo)'**
   String get shortcutsList;
 
   /// No description provided for @print.

lib/l10n/app_localizations_en.dart

@@ -29,7 +29,7 @@ class AppLocalizationsEn extends AppLocalizations {
 
   @override
   String get shortcutsList =>
-      '• Left/Right arrow — previous/next image\n• Ctrl+S — save visible area (JPEG 93)\n• Ctrl+Q — close window\n• Ctrl+Shift+Q — close all windows\n• Double click — toggle fill/fit\n• Right-drag — contrast\n• Shift+right-drag — rotate\n• Ctrl+right-drag — saturation\n• Ctrl+Shift+right-drag — brightness';
+      '• Left/Right arrow — previous/next image\n• Ctrl+S — save visible area (JPEG 93)\n• Ctrl+Q — close window\n• Ctrl+Shift+Q — close all windows\n• Double click — toggle fill/fit\n• Right-drag — contrast\n• Shift+right-drag — rotate\n• Ctrl+right-drag — saturation\n• Ctrl+Shift+right-drag — brightness\n• R — flip horizontally (resets effects, press again to undo)';
 
   @override
   String get print => 'Print';

lib/l10n/app_localizations_tr.dart

@@ -29,7 +29,7 @@ class AppLocalizationsTr extends AppLocalizations {
 
   @override
   String get shortcutsList =>
-      '• Sol/Sağ ok — önceki/sonraki resim\n• Ctrl+S — görünen alanı kaydet (JPEG 93)\n• Ctrl+Q — pencereyi kapat\n• Ctrl+Shift+Q — tüm pencereleri kapat\n• Çift tık — doldur/sığdır geçişi\n• Sağ tık sürükle — kontrast\n• Shift+sağ tık — döndür\n• Ctrl+sağ tık — doygunluk\n• Ctrl+Shift+sağ tık — parlaklık';
+      '• Sol/Sağ ok — önceki/sonraki resim\n• Ctrl+S — görünen alanı kaydet (JPEG 93)\n• Ctrl+Q — pencereyi kapat\n• Ctrl+Shift+Q — tüm pencereleri kapat\n• Çift tık — doldur/sığdır geçişi\n• Sağ tık sürükle — kontrast\n• Shift+sağ tık — döndür\n• Ctrl+sağ tık — doygunluk\n• Ctrl+Shift+sağ tık — parlaklık\n• R — yatay aynala (efektleri sıfırlar, tekrar basınca geri alır)';
 
   @override
   String get print => 'Yazdır';

lib/l10n/app_tr.arb

@@ -6,7 +6,7 @@
   "sortByName": "İsme göre",
   "appDescription": "Ultra hafif ve hızlı resim görüntüleyici. Görselleri açın, gezinti için okları veya klavye tuşlarını kullanın.",
   "shortcuts": "Kısayollar",
-  "shortcutsList": "• Sol/Sağ ok — önceki/sonraki resim\n• Ctrl+S — görünen alanı kaydet (JPEG 93)\n• Ctrl+Q — pencereyi kapat\n• Ctrl+Shift+Q — tüm pencereleri kapat\n• Çift tık — doldur/sığdır geçişi\n• Sağ tık sürükle — kontrast\n• Shift+sağ tık — döndür\n• Ctrl+sağ tık — doygunluk\n• Ctrl+Shift+sağ tık — parlaklık",
+  "shortcutsList": "• Sol/Sağ ok — önceki/sonraki resim\n• Ctrl+S — görünen alanı kaydet (JPEG 93)\n• Ctrl+Q — pencereyi kapat\n• Ctrl+Shift+Q — tüm pencereleri kapat\n• Çift tık — doldur/sığdır geçişi\n• Sağ tık sürükle — kontrast\n• Shift+sağ tık — döndür\n• Ctrl+sağ tık — doygunluk\n• Ctrl+Shift+sağ tık — parlaklık\n• R — yatay aynala (efektleri sıfırlar, tekrar basınca geri alır)",
   "print": "Yazdır",
   "close": "Kapat",
   "saveCrop": "Görünen alanı kaydet (JPEG 93)",

lib/services/crop_save_service.dart

@@ -17,6 +17,7 @@ class CropViewParams {
   final double vw, vh; // viewport boyutu
   final double tx, ty, sc; // pan/zoom
   final double angleDeg; // donus (derece)
+  final bool flipH; // yatay aynalama (goruntunun kendisi degil, gorunum)
   final double cx, cy; // donus merkezi (viewport ortasi)
   final double k; // kaynak -> layout olcegi
   final double ox, oy; // layout offset
@@ -29,6 +30,7 @@ class CropViewParams {
     required this.ty,
     required this.sc,
     required this.angleDeg,
+    this.flipH = false,
     required this.cx,
     required this.cy,
     required this.k,
@@ -73,6 +75,8 @@ class CropSaveService {
     final out = vp.angleDeg == 0
         ? _cropAxisAligned(source, vp)
         : _cropRotated(source, vp);
+    // Ekranda yatay aynalama acikken cikti da aynalanir (cikti = viewport'un birebir eslemesi).
+    if (vp.flipH) img.flipHorizontal(out);
     // Çıktıda yön fiziksel — EXIF tag'ini temizle (çift dönüşü önler).
     out.exif.imageIfd.orientation = null;
 

lib/widgets/image_canvas.dart

@@ -26,6 +26,7 @@ class ImageCanvasState extends State<ImageCanvas> {
   double _contrast = 1.0;
   double _saturation = 1.0;
   double _brightness = 0;
+  bool _flipH = false;
 
   // ── Gesture tracking ──
   String _interactionMode = 'none'; // 'contrast' | 'rotate' | 'saturation' | 'brightness'
@@ -165,6 +166,13 @@ class ImageCanvasState extends State<ImageCanvas> {
   bool _onHardwareKey(KeyEvent event) {
     final key = event.logicalKey;
     if (event is KeyDownEvent) {
+      if (key == LogicalKeyboardKey.keyR &&
+          !HardwareKeyboard.instance.isControlPressed &&
+          !HardwareKeyboard.instance.isShiftPressed &&
+          !HardwareKeyboard.instance.isAltPressed) {
+        _toggleFlipH();
+        return true;
+      }
       if (key == LogicalKeyboardKey.controlLeft ||
           key == LogicalKeyboardKey.controlRight) {
         _ctrlPressed = true;
@@ -202,6 +210,7 @@ class ImageCanvasState extends State<ImageCanvas> {
   void _resetView() {
     _tx = 0; _ty = 0; _sc = 1.0; _isFilled = WindowPersistence.filled;
     _angle = 0; _contrast = 1.0; _saturation = 1.0; _brightness = 0;
+    _flipH = false;
     _usingFullRes = false;
     _imageSize = Size.zero;
     _markRenderDirty();
@@ -210,10 +219,19 @@ class ImageCanvasState extends State<ImageCanvas> {
   void _toggleFillFit() {
     _isFilled = !_isFilled; _tx = 0; _ty = 0; _sc = 1.0;
     _angle = 0; _contrast = 1.0; _saturation = 1.0; _brightness = 0;
+    _flipH = false;
     WindowPersistence.saveFilled(_isFilled);
     _markRenderDirty();
   }
 
+  /// R: sağ çift tık gibi efektleri sıfırlar ve yatay aynalar; tekrar basınca geri alır.
+  void _toggleFlipH() {
+    _flipH = !_flipH;
+    _angle = 0; _contrast = 1.0; _saturation = 1.0; _brightness = 0;
+    _interactionMode = 'none';
+    _markRenderDirty();
+  }
+
   void _handleDoubleTap() => _toggleFillFit();
 
   void _handleScroll(PointerScrollEvent e) {
@@ -261,6 +279,7 @@ class ImageCanvasState extends State<ImageCanvas> {
       _contrast = 1.0;
       _saturation = 1.0;
       _brightness = 0;
+      _flipH = false;
       _interactionMode = 'none';
       _markRenderDirty();
       _lastRightTapTime = null;
@@ -416,6 +435,7 @@ class ImageCanvasState extends State<ImageCanvas> {
       ty: _ty,
       sc: _sc,
       angleDeg: _angle,
+      flipH: _flipH,
       cx: _vpSize.width / 2,
       cy: _vpSize.height / 2,
       k: k,
@@ -518,12 +538,13 @@ class ImageCanvasState extends State<ImageCanvas> {
       },
     );
 
-    if (_angle != 0) {
+    if (_angle != 0 || _flipH) {
       imageContent = Transform(
         alignment: Alignment.topLeft,
         transform: Matrix4.identity()
           ..translate(vpCenterX, vpCenterY)
           ..rotateZ(angleRad)
+          ..scale(_flipH ? -1.0 : 1.0, 1.0)
           ..translate(-vpCenterX, -vpCenterY),
         child: imageContent,
       );