PPR-26: Book import workflow rework

app/lib/widgets/add_book/add_book_choice_sheet.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:papyrus/themes/design_tokens.dart';
 import 'package:papyrus/widgets/add_book/add_physical_book_sheet.dart';
-import 'package:papyrus/widgets/add_book/import_book_sheet.dart';
+import 'package:papyrus/widgets/add_book/book_import_sheet.dart';
 import 'package:papyrus/widgets/shared/bottom_sheet_handle.dart';
 
 /// Choice sheet for selecting digital import, physical entry, or optional online search.
@@ -15,7 +15,13 @@ class AddBookChoiceSheet extends StatefulWidget {
   final VoidCallback? onFindOnline;
 
   /// Show the choice sheet as a modal bottom sheet.
-  static Future<void> show(BuildContext context, {VoidCallback? onFindOnline}) async {
+  static Future<void> show(
+    BuildContext context, {
+    VoidCallback? onFindOnline,
+    DigitalBookFilePicker? digitalFilePicker,
+    BookImportProcessor? bookImportProcessor,
+    ImportedBookFileDeleter? deleteImportedBookFile,
+  }) async {
     Future<_AddBookChoice?>? sheetCompleted;
     final choice = await showModalBottomSheet<_AddBookChoice>(
       context: context,
@@ -40,8 +46,15 @@ class AddBookChoiceSheet extends StatefulWidget {
     }
 
     switch (choice) {
+      case _AddBookChoice.importDigital:
+        await BookImportSheet.show(
+          context,
+          pickFiles: digitalFilePicker,
+          processor: bookImportProcessor,
+          deleteBookFile: deleteImportedBookFile,
+        );
       case _AddBookChoice.addPhysical:
-        AddPhysicalBookSheet.show(context);
+        await AddPhysicalBookSheet.show(context);
       case _AddBookChoice.findOnline:
         onFindOnline?.call();
     }
@@ -53,7 +66,6 @@ class AddBookChoiceSheet extends StatefulWidget {
 
 class _AddBookChoiceSheetState extends State<AddBookChoiceSheet> {
   bool _isSelecting = false;
-  bool _showImport = false;
 
   void _select(_AddBookChoice choice) {
     if (_isSelecting) {
@@ -66,10 +78,6 @@ class _AddBookChoiceSheetState extends State<AddBookChoiceSheet> {
 
   @override
   Widget build(BuildContext context) {
-    if (_showImport) {
-      return const ImportBookSheet();
-    }
-
     final textTheme = Theme.of(context).textTheme;
 
     return Column(
@@ -84,7 +92,7 @@ class _AddBookChoiceSheetState extends State<AddBookChoiceSheet> {
           icon: Icons.upload_file,
           title: 'Import digital books',
           subtitle: 'EPUB, PDF, AZW3, MOBI, CBZ/CBR',
-          onTap: () => setState(() => _showImport = true),
+          onTap: () => _select(_AddBookChoice.importDigital),
         ),
         const SizedBox(height: Spacing.sm),
         _ChoiceOption(
@@ -107,7 +115,7 @@ class _AddBookChoiceSheetState extends State<AddBookChoiceSheet> {
   }
 }
 
-enum _AddBookChoice { addPhysical, findOnline }
+enum _AddBookChoice { importDigital, addPhysical, findOnline }
 
 class _ChoiceOption extends StatelessWidget {
   final IconData icon;

app/lib/widgets/add_book/add_book_sheet_scaffold.dart

@@ -0,0 +1,81 @@
+import 'package:flutter/material.dart';
+import 'package:papyrus/themes/design_tokens.dart';
+import 'package:papyrus/widgets/shared/bottom_sheet_handle.dart';
+
+/// Lays out an add-book sheet with fixed header and footer regions.
+class AddBookSheetScaffold extends StatelessWidget {
+  final String title;
+  final VoidCallback onClose;
+  final Widget body;
+  final Widget footer;
+  final bool canClose;
+
+  const AddBookSheetScaffold({
+    super.key,
+    required this.title,
+    required this.onClose,
+    required this.body,
+    required this.footer,
+    this.canClose = true,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        final isCompactHeight = constraints.maxHeight < 280;
+        final verticalPadding = isCompactHeight ? 0.0 : Spacing.md;
+        final handleSpacing = isCompactHeight ? 0.0 : Spacing.lg;
+
+        return Column(
+          children: [
+            Container(
+              key: const Key('add-book-sheet-header'),
+              padding: EdgeInsets.fromLTRB(Spacing.lg, verticalPadding, Spacing.lg, verticalPadding),
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.stretch,
+                children: [
+                  const BottomSheetHandle(),
+                  SizedBox(height: handleSpacing),
+                  Row(
+                    children: [
+                      Expanded(
+                        child: Text(
+                          title,
+                          maxLines: isCompactHeight ? 1 : 2,
+                          overflow: TextOverflow.ellipsis,
+                          style: Theme.of(context).textTheme.headlineSmall,
+                          textScaler: isCompactHeight ? TextScaler.noScaling : null,
+                        ),
+                      ),
+                      IconButton(
+                        constraints: isCompactHeight ? const BoxConstraints.tightFor(width: 44, height: 44) : null,
+                        icon: const Icon(Icons.close),
+                        padding: isCompactHeight ? EdgeInsets.zero : null,
+                        tooltip: 'Close',
+                        onPressed: canClose ? onClose : null,
+                      ),
+                    ],
+                  ),
+                ],
+              ),
+            ),
+            const Divider(height: 1),
+            Expanded(child: body),
+            Container(
+              key: const Key('add-book-sheet-footer'),
+              padding: EdgeInsets.symmetric(horizontal: Spacing.lg, vertical: verticalPadding),
+              decoration: BoxDecoration(
+                color: colorScheme.surface,
+                border: Border(top: BorderSide(color: colorScheme.outlineVariant)),
+              ),
+              child: SafeArea(top: false, child: footer),
+            ),
+          ],
+        );
+      },
+    );
+  }
+}

app/lib/widgets/add_book/add_physical_book_sheet.dart

@@ -7,13 +7,12 @@ import 'package:papyrus/models/book.dart';
 import 'package:papyrus/services/metadata_service.dart';
 import 'package:papyrus/themes/design_tokens.dart';
 import 'package:papyrus/utils/image_utils.dart';
+import 'package:papyrus/widgets/add_book/add_book_sheet_scaffold.dart';
 import 'package:papyrus/widgets/add_book/isbn_scanner_dialog.dart';
 import 'package:papyrus/widgets/book_edit/cover_image_picker.dart';
 import 'package:papyrus/widgets/book_form/book_date_field.dart';
 import 'package:papyrus/widgets/book_form/book_text_field.dart';
 import 'package:papyrus/widgets/book_form/co_author_editor.dart';
-import 'package:papyrus/widgets/shared/bottom_sheet_handle.dart';
-import 'package:papyrus/widgets/shared/bottom_sheet_header.dart';
 import 'package:provider/provider.dart';
 import 'package:uuid/uuid.dart';
 
@@ -269,66 +268,51 @@ class _PhysicalBookContentState extends State<_PhysicalBookContent> {
       padding: EdgeInsets.only(bottom: MediaQuery.of(context).viewInsets.bottom),
       child: Form(
         key: _formKey,
-        child: Column(
-          children: [
-            // Fixed header
-            Padding(
-              padding: const EdgeInsets.fromLTRB(Spacing.md, Spacing.md, Spacing.md, 0),
-              child: Column(
-                children: [
-                  const BottomSheetHandle(),
-                  const SizedBox(height: Spacing.md),
-                  BottomSheetHeader(
-                    title: 'Add physical book',
-                    onCancel: () => Navigator.pop(context),
-                    onSave: _onSave,
-                    saveLabel: 'Add',
-                    canSave: _canSave,
-                  ),
-                ],
-              ),
-            ),
-            const SizedBox(height: Spacing.md),
-            const Divider(height: 1),
-
-            // Scrollable form content
-            Expanded(
-              child: ListView(
-                controller: widget.scrollController,
-                padding: const EdgeInsets.symmetric(horizontal: Spacing.lg, vertical: Spacing.md),
+        child: AddBookSheetScaffold(
+          title: 'Add physical book',
+          onClose: () => Navigator.of(context).pop(),
+          body: ListView(
+            controller: widget.scrollController,
+            padding: const EdgeInsets.symmetric(horizontal: Spacing.lg, vertical: Spacing.md),
+            children: [
+              Column(
+                crossAxisAlignment: CrossAxisAlignment.stretch,
                 children: [
-                  Column(
-                    crossAxisAlignment: CrossAxisAlignment.stretch,
-                    children: [
-                      Card(
-                        margin: const EdgeInsets.only(bottom: Spacing.xs),
-                        child: Padding(
-                          padding: const EdgeInsets.all(Spacing.md),
-                          child: CoverImagePicker(
-                            initialUrl: _coverUrl,
-                            initialBytes: _coverImageBytes,
-                            onUrlChanged: (url) => setState(() => _coverUrl = url),
-                            onFileChanged: (bytes) => setState(() {
-                              _coverImageBytes = bytes;
-                              if (bytes != null) _coverUrl = null;
-                            }),
-                            coverWidth: 240,
-                          ),
-                        ),
+                  Card(
+                    margin: const EdgeInsets.only(bottom: Spacing.xs),
+                    child: Padding(
+                      padding: const EdgeInsets.all(Spacing.md),
+                      child: CoverImagePicker(
+                        initialUrl: _coverUrl,
+                        initialBytes: _coverImageBytes,
+                        onUrlChanged: (url) => setState(() => _coverUrl = url),
+                        onFileChanged: (bytes) => setState(() {
+                          _coverImageBytes = bytes;
+                          if (bytes != null) _coverUrl = null;
+                        }),
+                        coverWidth: 240,
                       ),
-
-                      _buildIsbnSection(),
-                      _buildBasicInfoSection(),
-                      _buildPublicationSection(),
-                      _buildIdentifiersSection(),
-                      _buildSeriesSection(),
-                      _buildPhysicalBookSection(),
-                    ],
+                    ),
                   ),
+
+                  _buildIsbnSection(),
+                  _buildBasicInfoSection(),
+                  _buildPublicationSection(),
+                  _buildIdentifiersSection(),
+                  _buildSeriesSection(),
+                  _buildPhysicalBookSection(),
                 ],
               ),
-            ),
-          ],
+            ],
+          ),
+          footer: Row(
+            mainAxisAlignment: MainAxisAlignment.end,
+            children: [
+              TextButton(onPressed: () => Navigator.of(context).pop(), child: const Text('Cancel')),
+              const SizedBox(width: Spacing.sm),
+              FilledButton(onPressed: _canSave ? _onSave : null, child: const Text('Add')),
+            ],
+          ),
         ),
       ),
     );

app/lib/widgets/add_book/book_import_batch_item.dart

@@ -0,0 +1,113 @@
+import 'package:flutter/foundation.dart';
+import 'package:papyrus/services/book_import_result.dart';
+
+@immutable
+class SelectedBookFile {
+  const SelectedBookFile({required this.name, required this.bytes});
+
+  final String name;
+
+  /// The import workflow takes ownership of these bytes; callers must not
+  /// mutate them after creating this file selection.
+  final Uint8List? bytes;
+}
+
+enum BookImportBatchStatus { queued, processing, ready, processingFailed, adding, added, commitFailed }
+
+@immutable
+class BookImportBatchItem {
+  const BookImportBatchItem._({
+    required this.id,
+    required this.file,
+    required this.status,
+    this.result,
+    this.errorMessage,
+  });
+
+  factory BookImportBatchItem.queued({required String id, required SelectedBookFile file}) {
+    return BookImportBatchItem._(id: id, file: file, status: BookImportBatchStatus.queued);
+  }
+
+  final String id;
+  final SelectedBookFile file;
+  final BookImportBatchStatus status;
+  final BookImportResult? result;
+  final String? errorMessage;
+
+  bool get canRetry => status == BookImportBatchStatus.processingFailed || status == BookImportBatchStatus.commitFailed;
+
+  bool get isSettled => status != BookImportBatchStatus.queued && status != BookImportBatchStatus.processing;
+
+  bool get hasTemporaryFile => result != null && status != BookImportBatchStatus.added;
+
+  BookImportBatchItem startProcessing() {
+    if (status != BookImportBatchStatus.queued && status != BookImportBatchStatus.processingFailed) {
+      throw StateError('Cannot start processing an item with status $status.');
+    }
+
+    return BookImportBatchItem._(id: id, file: file, status: BookImportBatchStatus.processing);
+  }
+
+  BookImportBatchItem processingSucceeded(BookImportResult value) {
+    if (status != BookImportBatchStatus.processing) {
+      throw StateError('Cannot complete processing for an item with status $status.');
+    }
+
+    return BookImportBatchItem._(id: id, file: file, status: BookImportBatchStatus.ready, result: value);
+  }
+
+  BookImportBatchItem processingFailed(String message) {
+    if (status != BookImportBatchStatus.processing) {
+      throw StateError('Cannot fail processing for an item with status $status.');
+    }
+
+    return BookImportBatchItem._(
+      id: id,
+      file: file,
+      status: BookImportBatchStatus.processingFailed,
+      errorMessage: message,
+    );
+  }
+
+  BookImportBatchItem startAdding() {
+    if (status != BookImportBatchStatus.ready && status != BookImportBatchStatus.commitFailed) {
+      throw StateError('Cannot start adding an item with status $status.');
+    }
+    final value = result;
+    if (value == null) {
+      throw StateError('Cannot add an item without a processed result.');
+    }
+
+    return BookImportBatchItem._(id: id, file: file, status: BookImportBatchStatus.adding, result: value);
+  }
+
+  BookImportBatchItem added() {
+    if (status != BookImportBatchStatus.adding) {
+      throw StateError('Cannot finish adding an item with status $status.');
+    }
+    final value = result;
+    if (value == null) {
+      throw StateError('Cannot finish adding an item without a processed result.');
+    }
+
+    return BookImportBatchItem._(id: id, file: file, status: BookImportBatchStatus.added, result: value);
+  }
+
+  BookImportBatchItem commitFailed(String message) {
+    if (status != BookImportBatchStatus.adding) {
+      throw StateError('Cannot fail adding an item with status $status.');
+    }
+    final value = result;
+    if (value == null) {
+      throw StateError('Cannot fail adding an item without a processed result.');
+    }
+
+    return BookImportBatchItem._(
+      id: id,
+      file: file,
+      status: BookImportBatchStatus.commitFailed,
+      result: value,
+      errorMessage: message,
+    );
+  }
+}