feat(sheets): position desktop sheets near cursor

lib/screens/media_detail_screen.dart

@@ -594,7 +594,6 @@ class _MediaDetailScreenState extends State<MediaDetailScreen>
     final isNumeric = mediaClient?.capabilities.numericUserRating ?? true;
     final hasRating = metadata.userRating != null && metadata.userRating! > 0;
     final starValue = hasRating ? metadata.userRating! / 2.0 : 0.0;
-    final activate = isNumeric ? () => _showRatingDialog(metadata, starValue) : () => _toggleLike(metadata);
 
     final iconData = isNumeric ? Symbols.star_rounded : Symbols.thumb_up_rounded;
     final activeIconColor = isNumeric ? Colors.amber : Colors.teal;
@@ -606,6 +605,9 @@ class _MediaDetailScreenState extends State<MediaDetailScreen>
     return ListenableBuilder(
       listenable: _ratingChipFocusNode,
       builder: (context, _) {
+        final activate = isNumeric
+            ? () => _showRatingDialog(context, metadata, starValue)
+            : () => _toggleLike(metadata);
         final colorScheme = Theme.of(context).colorScheme;
         final isKeyboardMode = InputModeTracker.isKeyboardMode(context);
         final showFocus = _ratingChipFocusNode.hasFocus && isKeyboardMode;
@@ -680,9 +682,9 @@ class _MediaDetailScreenState extends State<MediaDetailScreen>
     }
   }
 
-  void _showRatingDialog(MediaItem metadata, double currentStarValue) {
-    showModalBottomSheet(
-      context: context,
+  void _showRatingDialog(BuildContext sheetContext, MediaItem metadata, double currentStarValue) {
+    OverlaySheetController.showAdaptive(
+      sheetContext,
       builder: (context) => RatingBottomSheet(
         currentRating: currentStarValue,
         onRate: (stars) async {

lib/watch_together/screens/watch_together_screen.dart

@@ -19,6 +19,7 @@ import '../../utils/snackbar_helper.dart';
 import '../../widgets/dialog_action_button.dart';
 import '../../utils/video_player_navigation.dart';
 import '../../widgets/focused_scroll_scaffold.dart';
+import '../../widgets/overlay_sheet.dart';
 import '../models/watch_session.dart';
 import '../providers/watch_together_provider.dart';
 import '../services/recent_rooms_service.dart';
@@ -402,8 +403,8 @@ class _RecentRoomTile extends StatelessWidget {
   }
 
   void _showActions(BuildContext context) {
-    showModalBottomSheet(
-      context: context,
+    OverlaySheetController.showAdaptive(
+      context,
       builder: (context) => SafeArea(
         child: Column(
           mainAxisSize: MainAxisSize.min,
@@ -412,7 +413,7 @@ class _RecentRoomTile extends StatelessWidget {
               leading: const Icon(Symbols.edit_rounded),
               title: Text(t.watchTogether.renameRoom),
               onTap: () {
-                Navigator.pop(context);
+                OverlaySheetController.closeAdaptive(context);
                 onRename();
               },
             ),
@@ -420,7 +421,7 @@ class _RecentRoomTile extends StatelessWidget {
               leading: Icon(Symbols.delete_rounded, color: Theme.of(context).colorScheme.error),
               title: Text(t.watchTogether.removeRoom, style: TextStyle(color: Theme.of(context).colorScheme.error)),
               onTap: () {
-                Navigator.pop(context);
+                OverlaySheetController.closeAdaptive(context);
                 onRemove();
               },
             ),

lib/widgets/overlay_sheet.dart

@@ -214,6 +214,8 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
   BoxConstraints? _constraints;
   Color? _explicitBackgroundColor;
   Alignment _alignment = Alignment.bottomCenter;
+  Offset? _lastPointerPosition;
+  double? _sheetHorizontalAnchor;
 
   // Drag-to-dismiss state
   double _dragOffset = 0;
@@ -274,6 +276,7 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
 
     final completer = Completer<T?>();
     final entry = _OverlaySheetEntry(builder: builder, completer: completer, initialFocusNode: initialFocusNode);
+    final horizontalAnchor = _resolveSheetHorizontalAnchor(alignment);
 
     setState(() {
       _pageStack.add(entry);
@@ -284,6 +287,7 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
       _constraints = constraints;
       _explicitBackgroundColor = backgroundColor;
       _alignment = alignment;
+      _sheetHorizontalAnchor = horizontalAnchor;
       _dragOffset = 0;
       _isDragging = false;
     });
@@ -345,6 +349,7 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
         _isClosing = false;
         _dragOffset = 0;
         _isDragging = false;
+        _sheetHorizontalAnchor = null;
       });
       // Clear stale back-key flags. handleBackKeyAction sets
       // markClosedViaBackKey() expecting a route pop, but the overlay
@@ -355,6 +360,18 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
     });
   }
 
+  void _rememberPointerPosition(PointerEvent event) {
+    if (event.kind != PointerDeviceKind.mouse) return;
+    _lastPointerPosition = event.localPosition;
+  }
+
+  double? _resolveSheetHorizontalAnchor(Alignment alignment) {
+    if (!PlatformDetector.isDesktopOS() || PlatformDetector.isTV()) return null;
+    if (InputModeTracker.isKeyboardMode(context)) return null;
+    if (alignment.x != 0 || alignment.y <= 0) return null;
+    return _lastPointerPosition?.dx;
+  }
+
   void _autoFocus() {
     if (!InputModeTracker.isKeyboardMode(context)) return;
 
@@ -458,6 +475,10 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
 
     return _OverlaySheetScope(
       controller: _controller,
+      child: Listener(
+        behavior: HitTestBehavior.translucent,
+        onPointerDown: _rememberPointerPosition,
+        onPointerHover: _rememberPointerPosition,
         child: Stack(
           children: [
             widget.child,
@@ -478,6 +499,7 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
             ],
           ],
         ),
+      ),
     );
   }
 
@@ -586,8 +608,12 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
         canRequestFocus: false,
         skipTraversal: true,
         onKeyEvent: _handleKeyEvent,
-        child: Align(
+        child: CustomSingleChildLayout(
+          delegate: _OverlaySheetLayoutDelegate(
             alignment: _alignment,
+            horizontalAnchor: _sheetHorizontalAnchor,
+            edgePadding: isDesktop ? _OverlaySheetLayoutDelegate.desktopEdgePadding : 0,
+          ),
           child: AnimatedBuilder(
             animation: _slideCurve,
             builder: (context, child) {
@@ -654,3 +680,46 @@ class _OverlaySheetHostState extends State<OverlaySheetHost> with SingleTickerPr
     return sheet;
   }
 }
+
+class _OverlaySheetLayoutDelegate extends SingleChildLayoutDelegate {
+  static const desktopEdgePadding = 16.0;
+
+  final Alignment alignment;
+  final double? horizontalAnchor;
+  final double edgePadding;
+
+  const _OverlaySheetLayoutDelegate({
+    required this.alignment,
+    required this.horizontalAnchor,
+    required this.edgePadding,
+  });
+
+  @override
+  BoxConstraints getConstraintsForChild(BoxConstraints constraints) {
+    final size = constraints.biggest;
+    final maxWidth = size.width > edgePadding * 2 ? size.width - edgePadding * 2 : size.width;
+    return BoxConstraints.loose(Size(maxWidth, size.height));
+  }
+
+  @override
+  Offset getPositionForChild(Size size, Size childSize) {
+    final hasHorizontalPadding = edgePadding > 0 && size.width > childSize.width + edgePadding * 2;
+    final minLeft = hasHorizontalPadding ? edgePadding : 0.0;
+    final maxLeft = hasHorizontalPadding ? size.width - childSize.width - edgePadding : minLeft;
+    final left = horizontalAnchor == null
+        ? minLeft + (maxLeft - minLeft) * (alignment.x + 1) / 2
+        : (horizontalAnchor! - childSize.width / 2).clamp(minLeft, maxLeft).toDouble();
+
+    final maxTop = size.height > childSize.height ? size.height - childSize.height : 0.0;
+    final top = maxTop * (alignment.y + 1) / 2;
+
+    return Offset(left, top);
+  }
+
+  @override
+  bool shouldRelayout(_OverlaySheetLayoutDelegate oldDelegate) {
+    return alignment != oldDelegate.alignment ||
+        horizontalAnchor != oldDelegate.horizontalAnchor ||
+        edgePadding != oldDelegate.edgePadding;
+  }
+}