UI enhancements

app/lib/widgets/add_book/add_book_choice_sheet.dart

@@ -5,7 +5,7 @@ import 'package:papyrus/widgets/add_book/import_book_sheet.dart';
 import 'package:papyrus/widgets/shared/bottom_sheet_handle.dart';
 
 /// Choice sheet for selecting how to add a book: digital import or physical.
-class AddBookChoiceSheet extends StatelessWidget {
+class AddBookChoiceSheet extends StatefulWidget {
   const AddBookChoiceSheet({required this.callerContext, super.key});
 
   /// The context of the page that opened this sheet.
@@ -18,48 +18,57 @@ class AddBookChoiceSheet extends StatelessWidget {
   static Future<void> show(BuildContext context) {
     return showModalBottomSheet(
       context: context,
+      isScrollControlled: true,
       useRootNavigator: true,
       useSafeArea: true,
       shape: const RoundedRectangleBorder(borderRadius: BorderRadius.vertical(top: Radius.circular(AppRadius.xl))),
-      builder: (_) => Padding(
-        padding: const EdgeInsets.only(left: Spacing.lg, right: Spacing.lg, top: Spacing.md, bottom: Spacing.lg),
-        child: AddBookChoiceSheet(callerContext: context),
-      ),
+      builder: (_) => AddBookChoiceSheet(callerContext: context),
     );
   }
 
+  @override
+  State<AddBookChoiceSheet> createState() => _AddBookChoiceSheetState();
+}
+
+class _AddBookChoiceSheetState extends State<AddBookChoiceSheet> {
+  bool _showImport = false;
+
   @override
   Widget build(BuildContext context) {
+    if (_showImport) {
+      return const ImportBookSheet();
+    }
+
     final textTheme = Theme.of(context).textTheme;
 
-    return Column(
-      mainAxisSize: MainAxisSize.min,
-      crossAxisAlignment: CrossAxisAlignment.start,
-      children: [
-        const BottomSheetHandle(),
-        const SizedBox(height: Spacing.lg),
-        Text('Add book', style: textTheme.headlineSmall),
-        const SizedBox(height: Spacing.lg),
-        _ChoiceOption(
-          icon: Icons.upload_file,
-          title: 'Import digital books',
-          subtitle: 'EPUB, PDF, AZW3, MOBI, CBZ/CBR',
-          onTap: () {
-            Navigator.of(context).pop();
-            ImportBookSheet.show(callerContext);
-          },
-        ),
-        const SizedBox(height: Spacing.sm),
-        _ChoiceOption(
-          icon: Icons.menu_book,
-          title: 'Add physical book',
-          subtitle: 'Enter details manually',
-          onTap: () {
-            Navigator.of(context).pop();
-            AddPhysicalBookSheet.show(callerContext);
-          },
-        ),
-      ],
+    return Padding(
+      padding: const EdgeInsets.only(left: Spacing.lg, right: Spacing.lg, top: Spacing.md, bottom: Spacing.lg),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          const BottomSheetHandle(),
+          const SizedBox(height: Spacing.lg),
+          Text('Add book', style: textTheme.headlineSmall),
+          const SizedBox(height: Spacing.lg),
+          _ChoiceOption(
+            icon: Icons.upload_file,
+            title: 'Import digital books',
+            subtitle: 'EPUB, PDF, AZW3, MOBI, CBZ/CBR',
+            onTap: () => setState(() => _showImport = true),
+          ),
+          const SizedBox(height: Spacing.sm),
+          _ChoiceOption(
+            icon: Icons.menu_book,
+            title: 'Add physical book',
+            subtitle: 'Enter details manually',
+            onTap: () {
+              Navigator.of(context).pop();
+              AddPhysicalBookSheet.show(widget.callerContext);
+            },
+          ),
+        ],
+      ),
     );
   }
 }

app/lib/widgets/add_book/import_book_sheet.dart

@@ -24,7 +24,13 @@ enum _ImportState { idle, processing, success, error }
 /// Opens a file picker, processes the file in a Web Worker,
 /// previews the extracted metadata, and adds the book to the library.
 class ImportBookSheet extends StatelessWidget {
-  const ImportBookSheet({super.key});
+  const ImportBookSheet({super.key}) : initialResult = null, initialCommitting = false;
+
+  @visibleForTesting
+  const ImportBookSheet.withInitialResult(this.initialResult, {this.initialCommitting = false, super.key});
+
+  final BookImportResult? initialResult;
+  final bool initialCommitting;
 
   /// Show the import sheet as a scrollable, content-sized bottom sheet.
   static Future<void> show(BuildContext context) {
@@ -34,16 +40,23 @@ class ImportBookSheet extends StatelessWidget {
       useRootNavigator: true,
       useSafeArea: true,
       shape: const RoundedRectangleBorder(borderRadius: BorderRadius.vertical(top: Radius.circular(AppRadius.xl))),
-      builder: (_) => const SingleChildScrollView(child: _ImportContent()),
+      builder: (_) => const ImportBookSheet(),
     );
   }
 
   @override
-  Widget build(BuildContext context) => const SizedBox.shrink();
+  Widget build(BuildContext context) {
+    return SingleChildScrollView(
+      child: _ImportContent(initialResult: initialResult, initialCommitting: initialCommitting),
+    );
+  }
 }
 
 class _ImportContent extends StatefulWidget {
-  const _ImportContent();
+  const _ImportContent({this.initialResult, this.initialCommitting = false});
+
+  final BookImportResult? initialResult;
+  final bool initialCommitting;
 
   @override
   State<_ImportContent> createState() => _ImportContentState();
@@ -53,11 +66,19 @@ class _ImportContentState extends State<_ImportContent> {
   static const double _pendingContentHeight = 232;
 
   final _importService = BookImportService();
-  _ImportState _state = _ImportState.idle;
+  late _ImportState _state;
   String? _filename;
   String? _errorMessage;
   BookImportResult? _result;
 
+  @override
+  void initState() {
+    super.initState();
+    _result = widget.initialResult;
+    _state = _result == null ? _ImportState.idle : _ImportState.success;
+    _committing = widget.initialCommitting;
+  }
+
   @override
   void dispose() {
     _importService.dispose();
@@ -82,7 +103,7 @@ class _ImportContentState extends State<_ImportContent> {
   }
 
   bool _picking = false;
-  bool _committing = false;
+  late bool _committing;
 
   Future<void> _pickAndProcess() async {
     if (_picking || _committing) return;
@@ -184,13 +205,10 @@ class _ImportContentState extends State<_ImportContent> {
     } catch (error) {
       if (!mounted) return;
       setState(() {
+        _committing = false;
         _state = _ImportState.error;
         _errorMessage = error.toString();
       });
-    } finally {
-      if (mounted) {
-        setState(() => _committing = false);
-      }
     }
 
     if (!mounted || committedBook == null) return;
@@ -343,12 +361,37 @@ class _ImportContentState extends State<_ImportContent> {
                           _filename = null;
                         });
                       },
+                style: OutlinedButton.styleFrom(
+                  shape: const StadiumBorder(),
+                  disabledForegroundColor: colorScheme.primary,
+                  side: BorderSide(color: colorScheme.outline, width: BorderWidths.thin),
+                ),
                 child: const Text('Pick different file'),
               ),
             ),
             const SizedBox(width: Spacing.md),
             Expanded(
-              child: FilledButton(onPressed: _committing ? null : _addToLibrary, child: const Text('Add to library')),
+              child: FilledButton(
+                onPressed: _committing ? null : _addToLibrary,
+                style: FilledButton.styleFrom(
+                  shape: const StadiumBorder(),
+                  disabledBackgroundColor: colorScheme.primary,
+                  disabledForegroundColor: colorScheme.onPrimary,
+                ),
+                child: _committing
+                    ? Row(
+                        mainAxisSize: MainAxisSize.min,
+                        children: [
+                          SizedBox.square(
+                            dimension: 16,
+                            child: CircularProgressIndicator(strokeWidth: 2, color: colorScheme.onPrimary),
+                          ),
+                          const SizedBox(width: Spacing.sm),
+                          const Text('Adding...'),
+                        ],
+                      )
+                    : const Text('Add to library'),
+              ),
             ),
           ],
         ),

app/test/widgets/add_book/add_book_sheets_test.dart

@@ -1,18 +1,45 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
+import 'package:papyrus/services/book_import_result.dart';
+import 'package:papyrus/themes/app_theme.dart';
 import 'package:papyrus/widgets/add_book/add_book_choice_sheet.dart';
 import 'package:papyrus/widgets/add_book/import_book_sheet.dart';
 import 'package:papyrus/widgets/shared/bottom_sheet_handle.dart';
 import 'package:papyrus/widgets/shared/bottom_sheet_header.dart';
 
+class _CountingNavigatorObserver extends NavigatorObserver {
+  int pushCount = 0;
+
+  @override
+  void didPush(Route<dynamic> route, Route<dynamic>? previousRoute) {
+    pushCount += 1;
+    super.didPush(route, previousRoute);
+  }
+}
+
+const importedBook = BookImportResult(
+  bookId: 'book-1',
+  title: 'Frankenstein',
+  author: 'Mary Wollstonecraft Shelley',
+  pageCount: 239,
+  fileSize: 1024,
+  fileHash: 'hash',
+  fileExtension: 'epub',
+);
+
 void main() {
-  Future<void> pumpLauncher(WidgetTester tester, VoidCallback Function(BuildContext) action) async {
+  Future<void> pumpLauncher(
+    WidgetTester tester,
+    VoidCallback Function(BuildContext) action, {
+    List<NavigatorObserver> navigatorObservers = const [],
+  }) async {
     tester.view.devicePixelRatio = 1;
     tester.view.physicalSize = const Size(1400, 1000);
     addTearDown(tester.view.reset);
 
     await tester.pumpWidget(
       MaterialApp(
+        navigatorObservers: navigatorObservers,
         home: Builder(
           builder: (context) => Scaffold(
             body: FilledButton(onPressed: action(context), child: const Text('Open')),
@@ -71,4 +98,67 @@ void main() {
       findsNothing,
     );
   });
+
+  testWidgets('digital import transition preserves the modal backdrop', (tester) async {
+    final observer = _CountingNavigatorObserver();
+    await pumpLauncher(
+      tester,
+      (context) =>
+          () => AddBookChoiceSheet.show(context),
+      navigatorObservers: [observer],
+    );
+    await tester.tap(find.text('Open'));
+    await tester.pumpAndSettle();
+
+    final dimmingBarrier = find.byWidgetPredicate((widget) => widget is ModalBarrier && widget.color != null);
+    final initialPushCount = observer.pushCount;
+    final initialBarrier = tester.element(dimmingBarrier);
+
+    await tester.tap(find.text('Import digital books'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Import book'), findsOneWidget);
+    expect(dimmingBarrier, findsOneWidget);
+    expect(tester.element(dimmingBarrier), same(initialBarrier));
+    expect(observer.pushCount, initialPushCount);
+  });
+
+  testWidgets('successful import actions can be rendered for widget verification', (tester) async {
+    await tester.pumpWidget(const MaterialApp(home: Scaffold(body: ImportBookSheet.withInitialResult(importedBook))));
+
+    expect(find.text('Pick different file'), findsOneWidget);
+    expect(find.text('Add to library'), findsOneWidget);
+
+    final pickButton = tester.widget<OutlinedButton>(find.widgetWithText(OutlinedButton, 'Pick different file'));
+    final addButton = tester.widget<FilledButton>(find.widgetWithText(FilledButton, 'Add to library'));
+
+    expect(pickButton.style?.shape?.resolve({}), isA<StadiumBorder>());
+    expect(addButton.style?.shape?.resolve({}), isA<StadiumBorder>());
+  });
+
+  testWidgets('committing import actions stay visually stable and show progress', (tester) async {
+    await tester.pumpWidget(
+      MaterialApp(
+        theme: AppTheme.dark,
+        home: const Scaffold(body: ImportBookSheet.withInitialResult(importedBook, initialCommitting: true)),
+      ),
+    );
+
+    final pickButton = tester.widget<OutlinedButton>(find.widgetWithText(OutlinedButton, 'Pick different file'));
+    final addButton = tester.widget<FilledButton>(find.byType(FilledButton));
+
+    expect(pickButton.onPressed, isNull);
+    expect(addButton.onPressed, isNull);
+    expect(find.text('Adding...'), findsOneWidget);
+    expect(find.text('Add to library'), findsNothing);
+    expect(find.byType(CircularProgressIndicator), findsOneWidget);
+
+    final colorScheme = Theme.of(tester.element(find.text('Adding...'))).colorScheme;
+    const disabled = <WidgetState>{WidgetState.disabled};
+
+    expect(pickButton.style?.foregroundColor?.resolve(disabled), colorScheme.primary);
+    expect(pickButton.style?.side?.resolve(disabled)?.color, colorScheme.outline);
+    expect(addButton.style?.backgroundColor?.resolve(disabled), colorScheme.primary);
+    expect(addButton.style?.foregroundColor?.resolve(disabled), colorScheme.onPrimary);
+  });
 }