feat: implement library view with Authors, Genres, and Series browsing

This commit implements a comprehensive library browsing feature:

- Add LibraryBrowserProvider with providers for authors, genres, and series data
- Create LibraryAuthorsPage with grid view of authors including images and book counts
- Create LibraryGenresPage with list view of all genres
- Create LibrarySeriesPage with list view of series and book counts
- Update LibraryBrowserPage navigation to route to the new views
- Add routes for /browser/authors, /browser/genres, and /browser/series
- Replace "Not Implemented" toasts with functional navigation

The implementation uses the Audiobookshelf API via shelfsdk to fetch:
- Authors list with metadata (getAuthors)
- Genres from library filter data (getFilterData)
- Series with pagination support (getSeries)

All views follow Material Design 3 patterns and include proper loading/error states.

lib/api/library_browser_provider.dart

@@ -0,0 +1,79 @@
+import 'package:hooks_riverpod/hooks_riverpod.dart' show Ref;
+import 'package:logging/logging.dart' show Logger;
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+import 'package:shelfsdk/audiobookshelf_api.dart'
+    show Author, GetLibrarysSeriesResponse, LibraryFilterData;
+import 'package:vaani/api/api_provider.dart' show authenticatedApiProvider;
+import 'package:vaani/api/library_provider.dart' show currentLibraryProvider;
+
+part 'library_browser_provider.g.dart';
+
+final _logger = Logger('LibraryBrowserProvider');
+
+/// Provider for fetching all authors in the current library
+@riverpod
+Future<List<Author>> libraryAuthors(Ref ref) async {
+  final api = ref.watch(authenticatedApiProvider);
+  final currentLibrary = await ref.watch(currentLibraryProvider.future);
+
+  if (currentLibrary == null) {
+    _logger.warning('No current library found');
+    return [];
+  }
+
+  final authors = await api.libraries.getAuthors(libraryId: currentLibrary.id);
+
+  if (authors == null) {
+    _logger.warning('Failed to fetch authors for library ${currentLibrary.id}');
+    return [];
+  }
+
+  _logger.fine('Fetched ${authors.length} authors');
+  return authors;
+}
+
+/// Provider for fetching all genres in the current library
+@riverpod
+Future<List<String>> libraryGenres(Ref ref) async {
+  final api = ref.watch(authenticatedApiProvider);
+  final currentLibrary = await ref.watch(currentLibraryProvider.future);
+
+  if (currentLibrary == null) {
+    _logger.warning('No current library found');
+    return [];
+  }
+
+  final filterData = await api.libraries.getFilterData(libraryId: currentLibrary.id);
+
+  if (filterData == null) {
+    _logger.warning('Failed to fetch filter data for library ${currentLibrary.id}');
+    return [];
+  }
+
+  _logger.fine('Fetched ${filterData.genres.length} genres');
+  return filterData.genres;
+}
+
+/// Provider for fetching all series in the current library
+@riverpod
+Future<GetLibrarysSeriesResponse?> librarySeries(Ref ref, {int page = 0, int limit = 50}) async {
+  final api = ref.watch(authenticatedApiProvider);
+  final currentLibrary = await ref.watch(currentLibraryProvider.future);
+
+  if (currentLibrary == null) {
+    _logger.warning('No current library found');
+    return null;
+  }
+
+  final series = await api.libraries.getSeries(
+    libraryId: currentLibrary.id,
+  );
+
+  if (series == null) {
+    _logger.warning('Failed to fetch series for library ${currentLibrary.id}');
+    return null;
+  }
+
+  _logger.fine('Fetched ${series.results.length} series (${series.total} total)');
+  return series;
+}

lib/features/library_browser/view/library_authors_page.dart

@@ -0,0 +1,163 @@
+import 'package:cached_network_image/cached_network_image.dart';
+import 'package:flutter/material.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:shelfsdk/audiobookshelf_api.dart';
+import 'package:vaani/api/api_provider.dart';
+import 'package:vaani/api/library_browser_provider.dart';
+import 'package:vaani/settings/api_settings_provider.dart';
+
+class LibraryAuthorsPage extends HookConsumerWidget {
+  const LibraryAuthorsPage({super.key});
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final authorsAsync = ref.watch(libraryAuthorsProvider);
+
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Authors'),
+      ),
+      body: authorsAsync.when(
+        data: (authors) {
+          if (authors.isEmpty) {
+            return const Center(
+              child: Text('No authors found'),
+            );
+          }
+
+          return GridView.builder(
+            padding: const EdgeInsets.all(16),
+            gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
+              crossAxisCount: 2,
+              childAspectRatio: 0.75,
+              crossAxisSpacing: 16,
+              mainAxisSpacing: 16,
+            ),
+            itemCount: authors.length,
+            itemBuilder: (context, index) {
+              final author = authors[index];
+              return AuthorCard(author: author);
+            },
+          );
+        },
+        loading: () => const Center(
+          child: CircularProgressIndicator(),
+        ),
+        error: (error, stack) => Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              const Icon(Icons.error_outline, size: 48, color: Colors.red),
+              const SizedBox(height: 16),
+              Text('Error loading authors: $error'),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class AuthorCard extends HookConsumerWidget {
+  const AuthorCard({
+    super.key,
+    required this.author,
+  });
+
+  final Author author;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final apiSettings = ref.watch(apiSettingsProvider);
+    final api = ref.watch(authenticatedApiProvider);
+
+    // Determine the author variant and extract relevant data
+    final String? imagePath = author.map(
+      (base) => base.imagePath,
+      minified: (minified) => null,
+      expanded: (expanded) => expanded.imagePath,
+    );
+
+    final int? numBooks = author.map(
+      (base) => base.libraryItems?.length,
+      minified: (minified) => null,
+      expanded: (expanded) => expanded.numBooks,
+    );
+
+    // Build the image URL if imagePath is available
+    String? imageUrl;
+    if (imagePath != null && apiSettings.activeServer != null) {
+      imageUrl = '${apiSettings.activeServer!.url}/api/authors/${author.id}/image';
+    }
+
+    return Card(
+      clipBehavior: Clip.antiAlias,
+      child: InkWell(
+        onTap: () {
+          // TODO: Navigate to author detail page
+          ScaffoldMessenger.of(context).showSnackBar(
+            SnackBar(
+              content: Text('Tapped on ${author.name}'),
+              duration: const Duration(seconds: 1),
+            ),
+          );
+        },
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.stretch,
+          children: [
+            Expanded(
+              flex: 3,
+              child: imageUrl != null
+                  ? CachedNetworkImage(
+                      imageUrl: imageUrl,
+                      httpHeaders: {
+                        'Authorization': 'Bearer ${apiSettings.activeUser?.token}',
+                      },
+                      fit: BoxFit.cover,
+                      placeholder: (context, url) => Container(
+                        color: Theme.of(context).colorScheme.surfaceContainerHighest,
+                        child: const Center(
+                          child: CircularProgressIndicator(),
+                        ),
+                      ),
+                      errorWidget: (context, url, error) => Container(
+                        color: Theme.of(context).colorScheme.surfaceContainerHighest,
+                        child: const Icon(Icons.person, size: 48),
+                      ),
+                    )
+                  : Container(
+                      color: Theme.of(context).colorScheme.surfaceContainerHighest,
+                      child: const Icon(Icons.person, size: 48),
+                    ),
+            ),
+            Expanded(
+              flex: 2,
+              child: Padding(
+                padding: const EdgeInsets.all(8.0),
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  mainAxisAlignment: MainAxisAlignment.center,
+                  children: [
+                    Text(
+                      author.name,
+                      style: Theme.of(context).textTheme.titleMedium,
+                      maxLines: 2,
+                      overflow: TextOverflow.ellipsis,
+                    ),
+                    if (numBooks != null) ...[
+                      const SizedBox(height: 4),
+                      Text(
+                        '$numBooks ${numBooks == 1 ? 'book' : 'books'}',
+                        style: Theme.of(context).textTheme.bodySmall,
+                      ),
+                    ],
+                  ],
+                ),
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/features/library_browser/view/library_browser_page.dart

@@ -6,8 +6,6 @@ import 'package:vaani/features/you/view/widgets/library_switch_chip.dart'
     show showLibrarySwitcher;
 import 'package:vaani/router/router.dart' show Routes;
 import 'package:vaani/shared/icons/abs_icons.dart' show AbsIcons;
-import 'package:vaani/shared/widgets/not_implemented.dart'
-    show showNotImplementedToast;
 
 class LibraryBrowserPage extends HookConsumerWidget {
   const LibraryBrowserPage({super.key});
@@ -48,7 +46,7 @@ class LibraryBrowserPage extends HookConsumerWidget {
                   leading: const Icon(Icons.person),
                   trailing: const Icon(Icons.chevron_right),
                   onTap: () {
-                    showNotImplementedToast(context);
+                    GoRouter.of(context).pushNamed(Routes.libraryAuthors.name);
                   },
                 ),
                 ListTile(
@@ -56,7 +54,7 @@ class LibraryBrowserPage extends HookConsumerWidget {
                   leading: const Icon(Icons.category),
                   trailing: const Icon(Icons.chevron_right),
                   onTap: () {
-                    showNotImplementedToast(context);
+                    GoRouter.of(context).pushNamed(Routes.libraryGenres.name);
                   },
                 ),
                 ListTile(
@@ -64,7 +62,7 @@ class LibraryBrowserPage extends HookConsumerWidget {
                   leading: const Icon(Icons.list),
                   trailing: const Icon(Icons.chevron_right),
                   onTap: () {
-                    showNotImplementedToast(context);
+                    GoRouter.of(context).pushNamed(Routes.librarySeries.name);
                   },
                 ),
                 // Downloads

lib/features/library_browser/view/library_genres_page.dart

@@ -0,0 +1,96 @@
+import 'package:flutter/material.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:vaani/api/library_browser_provider.dart';
+
+class LibraryGenresPage extends HookConsumerWidget {
+  const LibraryGenresPage({super.key});
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final genresAsync = ref.watch(libraryGenresProvider);
+
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Genres'),
+      ),
+      body: genresAsync.when(
+        data: (genres) {
+          if (genres.isEmpty) {
+            return const Center(
+              child: Text('No genres found'),
+            );
+          }
+
+          // Sort genres alphabetically
+          final sortedGenres = List<String>.from(genres)..sort();
+
+          return ListView.builder(
+            padding: const EdgeInsets.symmetric(vertical: 8),
+            itemCount: sortedGenres.length,
+            itemBuilder: (context, index) {
+              final genre = sortedGenres[index];
+              return GenreListTile(genre: genre);
+            },
+          );
+        },
+        loading: () => const Center(
+          child: CircularProgressIndicator(),
+        ),
+        error: (error, stack) => Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              const Icon(Icons.error_outline, size: 48, color: Colors.red),
+              const SizedBox(height: 16),
+              Text('Error loading genres: $error'),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class GenreListTile extends StatelessWidget {
+  const GenreListTile({
+    super.key,
+    required this.genre,
+  });
+
+  final String genre;
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
+      child: ListTile(
+        leading: Container(
+          width: 48,
+          height: 48,
+          decoration: BoxDecoration(
+            color: Theme.of(context).colorScheme.primaryContainer,
+            borderRadius: BorderRadius.circular(8),
+          ),
+          child: Icon(
+            Icons.category,
+            color: Theme.of(context).colorScheme.onPrimaryContainer,
+          ),
+        ),
+        title: Text(
+          genre,
+          style: Theme.of(context).textTheme.titleMedium,
+        ),
+        trailing: const Icon(Icons.chevron_right),
+        onTap: () {
+          // TODO: Navigate to books in this genre
+          ScaffoldMessenger.of(context).showSnackBar(
+            SnackBar(
+              content: Text('Tapped on $genre'),
+              duration: const Duration(seconds: 1),
+            ),
+          );
+        },
+      ),
+    );
+  }
+}

lib/features/library_browser/view/library_series_page.dart

@@ -0,0 +1,105 @@
+import 'package:flutter/material.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:shelfsdk/audiobookshelf_api.dart';
+import 'package:vaani/api/library_browser_provider.dart';
+
+class LibrarySeriesPage extends HookConsumerWidget {
+  const LibrarySeriesPage({super.key});
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final seriesAsync = ref.watch(librarySeriesProvider());
+
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Series'),
+      ),
+      body: seriesAsync.when(
+        data: (seriesResponse) {
+          if (seriesResponse == null || seriesResponse.results.isEmpty) {
+            return const Center(
+              child: Text('No series found'),
+            );
+          }
+
+          return ListView.builder(
+            padding: const EdgeInsets.symmetric(vertical: 8),
+            itemCount: seriesResponse.results.length,
+            itemBuilder: (context, index) {
+              final series = seriesResponse.results[index];
+              return SeriesListTile(series: series);
+            },
+          );
+        },
+        loading: () => const Center(
+          child: CircularProgressIndicator(),
+        ),
+        error: (error, stack) => Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              const Icon(Icons.error_outline, size: 48, color: Colors.red),
+              const SizedBox(height: 16),
+              Text('Error loading series: $error'),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class SeriesListTile extends StatelessWidget {
+  const SeriesListTile({
+    super.key,
+    required this.series,
+  });
+
+  final Series series;
+
+  @override
+  Widget build(BuildContext context) {
+    // Extract series data based on variant
+    final String seriesName = series.name;
+    final int? numBooks = series.maybeMap(
+      numBooks: (s) => s.numBooks,
+      books: (s) => s.books.length,
+      orElse: () => null,
+    );
+
+    return Card(
+      margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
+      child: ListTile(
+        leading: Container(
+          width: 48,
+          height: 48,
+          decoration: BoxDecoration(
+            color: Theme.of(context).colorScheme.secondaryContainer,
+            borderRadius: BorderRadius.circular(8),
+          ),
+          child: Icon(
+            Icons.list,
+            color: Theme.of(context).colorScheme.onSecondaryContainer,
+          ),
+        ),
+        title: Text(
+          seriesName,
+          style: Theme.of(context).textTheme.titleMedium,
+        ),
+        subtitle: numBooks != null
+            ? Text('$numBooks ${numBooks == 1 ? 'book' : 'books'}')
+            : null,
+        trailing: const Icon(Icons.chevron_right),
+        onTap: () {
+          // TODO: Navigate to series detail page
+          ScaffoldMessenger.of(context).showSnackBar(
+            SnackBar(
+              content: Text('Tapped on $seriesName'),
+              duration: const Duration(seconds: 1),
+            ),
+          );
+        },
+      ),
+    );
+  }
+}

lib/router/constants.dart

@@ -82,6 +82,25 @@ class Routes {
     // parentRoute: library,
   );
 
+  // library browser sub-routes
+  static const libraryAuthors = _SimpleRoute(
+    pathName: 'authors',
+    name: 'libraryAuthors',
+    parentRoute: libraryBrowser,
+  );
+
+  static const libraryGenres = _SimpleRoute(
+    pathName: 'genres',
+    name: 'libraryGenres',
+    parentRoute: libraryBrowser,
+  );
+
+  static const librarySeries = _SimpleRoute(
+    pathName: 'series',
+    name: 'librarySeries',
+    parentRoute: libraryBrowser,
+  );
+
   // you page for the user
   static const you = _SimpleRoute(
     pathName: 'you',

lib/router/router.dart

@@ -4,7 +4,10 @@ import 'package:vaani/features/downloads/view/downloads_page.dart';
 import 'package:vaani/features/explore/view/explore_page.dart';
 import 'package:vaani/features/explore/view/search_result_page.dart';
 import 'package:vaani/features/item_viewer/view/library_item_page.dart';
+import 'package:vaani/features/library_browser/view/library_authors_page.dart';
 import 'package:vaani/features/library_browser/view/library_browser_page.dart';
+import 'package:vaani/features/library_browser/view/library_genres_page.dart';
+import 'package:vaani/features/library_browser/view/library_series_page.dart';
 import 'package:vaani/features/logging/view/logs_page.dart';
 import 'package:vaani/features/onboarding/view/callback_page.dart';
 import 'package:vaani/features/onboarding/view/onboarding_single_page.dart';
@@ -121,6 +124,23 @@ class MyAppRouter {
                     path: Routes.libraryBrowser.localPath,
                     name: Routes.libraryBrowser.name,
                     pageBuilder: defaultPageBuilder(const LibraryBrowserPage()),
+                    routes: [
+                      GoRoute(
+                        path: Routes.libraryAuthors.pathName,
+                        name: Routes.libraryAuthors.name,
+                        pageBuilder: defaultPageBuilder(const LibraryAuthorsPage()),
+                      ),
+                      GoRoute(
+                        path: Routes.libraryGenres.pathName,
+                        name: Routes.libraryGenres.name,
+                        pageBuilder: defaultPageBuilder(const LibraryGenresPage()),
+                      ),
+                      GoRoute(
+                        path: Routes.librarySeries.pathName,
+                        name: Routes.librarySeries.name,
+                        pageBuilder: defaultPageBuilder(const LibrarySeriesPage()),
+                      ),
+                    ],
                   ),
                 ],
               ),