added error handling for invalid urls

lib/model/collection.dart

@@ -7,12 +7,28 @@ class Collection {
     createdAt: json['createdAt'] as int,
   );
 
-  String name;
   int createdAt; // used as Id with millisecondsSinceEpoch
+  String name;
+
+  @override
+  bool operator ==(Object other) {
+    if (other is Collection) {
+      return hashCode == other.hashCode;
+    } else {
+      return false;
+    }
+  }
+
+  @override
+  int get hashCode => id.hashCode;
 
   int get id => createdAt;
 
   DateTime get createdDate => DateTime.fromMillisecondsSinceEpoch(createdAt);
 
   Map<String, dynamic> toJson() => {'name': name, 'createdAt': createdAt};
+
+  Collection copyWith({String? name}) {
+    return Collection(name: name ?? this.name, createdAt: createdAt);
+  }
 }

lib/pages/collection_page.dart

@@ -21,6 +21,14 @@ class CollectionPage extends StatefulWidget {
 class _CollectionPageState extends State<CollectionPage> {
   MapsLinkMetadata? selectedMapsLink;
 
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (selectedMapsLink != null) onAddButtonPressed();
+    });
+  }
+
   void onAddButtonPressed() => showDialog(
     context: context,
     builder: (context) => CreateBookmarkDialog(
@@ -37,30 +45,27 @@ class _CollectionPageState extends State<CollectionPage> {
       selectedBookmark: selectedBookmark,
       onSavePressed: onBookmarkSaved,
       onDeletePressed: () {
-        Storage.deleteBookmarkById(selectedBookmark.id);
-        setState(() {});
+        Storage.deleteBookmarkById(
+          selectedBookmark.id,
+        ).whenComplete(() => setState(() {}));
       },
     ),
   );
 
-  @override
-  void initState() {
-    super.initState();
-    WidgetsBinding.instance.addPostFrameCallback((_) {
-      if (selectedMapsLink != null) onAddButtonPressed();
-    });
-  }
-
   void onBookmarkSaved(Bookmark bookmark) {
     Storage.addOrUpdateBookmark(bookmark);
     setState(() {});
     context.read<SharedLinkProvider>().removeCurrentMapsLink();
   }
 
-  Widget bookmarkListBuilder(BuildContext context, Bookmark bookmark) {
+  Widget bookmarksListItemBuilder(BuildContext context, Bookmark bookmark) {
     return ListTile(
       title: Text(bookmark.name),
-      onTap: () => launchUrlFromString(bookmark.link),
+      onTap: () => launchUrlFromString(bookmark.link).then((errorCode) {
+        if (context.mounted && errorCode != UrlLaunchErrorCode.none) {
+          return showUrlError(context, errorCode);
+        }
+      }),
       onLongPress: () => editBookmark(bookmark),
     );
   }
@@ -95,7 +100,7 @@ class _CollectionPageState extends State<CollectionPage> {
       ),
       body: ListView.builder(
         itemBuilder: (context, index) =>
-            bookmarkListBuilder(context, bookmarks.elementAt(index)),
+            bookmarksListItemBuilder(context, bookmarks.elementAt(index)),
         itemCount: bookmarks.length,
       ),
       floatingActionButton: FloatingActionButton(
@@ -104,4 +109,16 @@ class _CollectionPageState extends State<CollectionPage> {
       ),
     );
   }
+
+  void showUrlError(BuildContext context, UrlLaunchErrorCode errorCode) {
+    String errorText = '';
+    if (errorCode == UrlLaunchErrorCode.couldNotLaunch) {
+      errorText = 'Could not launch Url';
+    } else {
+      errorText = 'Invalid Url';
+    }
+    ScaffoldMessenger.of(
+      context,
+    ).showSnackBar(SnackBar(content: Text(errorText)));
+  }
 }

lib/pages/collections_list_page.dart

@@ -10,6 +10,7 @@ import 'collection_page.dart';
 
 class CollectionsListPage extends StatefulWidget {
   const CollectionsListPage({super.key});
+
   static const String routeName = '/collections';
 
   @override
@@ -17,38 +18,8 @@ class CollectionsListPage extends StatefulWidget {
 }
 
 class _CollectionsListPageState extends State<CollectionsListPage> {
-  final collections = Storage.loadCollections();
   bool addingNewBookmark = false;
 
-  @override
-  Widget build(BuildContext context) {
-    final provider = context.watch<SharedLinkProvider>();
-    addingNewBookmark = provider.currentMapsLinkMetadata != null;
-    return Scaffold(
-      appBar: AppBar(
-        title: addingNewBookmark ? Text('Choose Collection') : null,
-        actions: [
-          if (addingNewBookmark)
-            TextButton(
-              onPressed: () => provider.removeCurrentMapsLink(),
-              child: Text('Cancel'),
-            ),
-        ],
-      ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: onAddButtonPressed,
-        child: Icon(Icons.add),
-      ),
-      body: ListView.builder(
-        itemBuilder: itemBuilder,
-        itemCount: collections.length,
-      ),
-      // bottomSheet: provider.currentMapsLinkMetadata == null
-      //     ? null
-      //     : BottomSheet(onClosing: () {}, builder: bottomSheetBuilder),
-    );
-  }
-
   Widget bottomSheetBuilder(BuildContext context) {
     final titleTextFieldController = TextEditingController(
       text: context
@@ -62,26 +33,25 @@ class _CollectionsListPageState extends State<CollectionsListPage> {
     );
   }
 
-  void onAddButtonPressed() =>
-      showDialog(
-        context: context,
-        builder: (context) =>
-            CreateBookmarkCollectionDialog(onSavePressed: onCollectionSaved),
-      ).whenComplete(() {
-        if (addingNewBookmark) navigateToCollection(collections.last.id);
-      });
+  void onAddButtonPressed() => showDialog(
+    context: context,
+    builder: (context) =>
+        CreateBookmarkCollectionDialog(onSavePressed: onCollectionSaved),
+  );
 
-  void onCollectionSaved(String name) {
-    collections.add(Collection(name: name));
-    Storage.saveCollections(collections);
+  void onCollectionSaved(Collection collection) {
+    Storage.addOrUpdateCollection(collection);
     setState(() {});
   }
 
-  Widget itemBuilder(BuildContext context, int index) {
-    final collection = collections.elementAt(index);
+  Widget collectionsListItemBuilder(
+    BuildContext context,
+    Collection collection,
+  ) {
     return ListTile(
       title: Text(collection.name),
       onTap: () => navigateToCollection(collection.id),
+      onLongPress: () => onEditCollection(collection),
     );
   }
 
@@ -90,8 +60,50 @@ class _CollectionsListPageState extends State<CollectionsListPage> {
     Navigator.pushNamed(context, CollectionPage.routeName);
   }
 
+  void onEditCollection(Collection selectedCollection) => showDialog(
+    context: context,
+    builder: (context) => CreateBookmarkCollectionDialog(
+      selectedCollection: selectedCollection,
+      onSavePressed: onCollectionSaved,
+      onDeletePressed: () {
+        Storage.deleteCollection(
+          selectedCollection,
+        ).whenComplete(() => setState(() {}));
+      },
+    ),
+  );
+
   @override
-  void didChangeDependencies() {
-    super.didChangeDependencies();
+  Widget build(BuildContext context) {
+    final collections = Storage.loadCollections();
+    final provider = context.watch<SharedLinkProvider>();
+    addingNewBookmark = provider.currentMapsLinkMetadata != null;
+    return Scaffold(
+      appBar: AppBar(
+        title: addingNewBookmark
+            ? Text('Choose Collection')
+            : Text('Collections'),
+        actions: [
+          if (addingNewBookmark)
+            TextButton(
+              onPressed: () => provider.removeCurrentMapsLink(),
+              child: Text('Cancel'),
+            ),
+        ],
+      ),
+      floatingActionButton: FloatingActionButton(
+        onPressed: onAddButtonPressed,
+        child: Icon(Icons.add),
+      ),
+      body: collections.isNotEmpty
+          ? ListView.builder(
+              itemBuilder: (context, index) => collectionsListItemBuilder(
+                context,
+                collections.elementAt(index),
+              ),
+              itemCount: collections.length,
+            )
+          : Center(child: Text('Create your first Collection to get started!')),
+    );
   }
 }

lib/service/storage.dart

@@ -6,10 +6,10 @@ import '../model/bookmark.dart';
 import '../model/collection.dart';
 
 class Storage {
-  static const String _collectionsKey = 'collections';
   static const String _bookmarksKey = 'bookmarks';
-  static const String _statsKey = 'stats';
+  static const String _collectionsKey = 'collections';
   static SharedPreferencesWithCache? _prefsWithCache;
+  static const String _statsKey = 'stats';
 
   static Future<void> initialize() async {
     _prefsWithCache = await SharedPreferencesWithCache.create(
@@ -19,15 +19,6 @@ class Storage {
     );
   }
 
-  static SharedPreferencesWithCache get _prefs {
-    if (_prefsWithCache == null) {
-      throw StateError(
-        'BookmarkStorage not initialized. Call initialize() first.',
-      );
-    }
-    return _prefsWithCache!;
-  }
-
   static List<Collection> loadCollections() {
     final jsonString = _prefs.getString(_collectionsKey) ?? '[]';
     final jsonList = jsonDecode(jsonString) as List;
@@ -36,12 +27,7 @@ class Storage {
         .toList();
   }
 
-  static Future<void> saveCollections(List<Collection> collections) async {
-    final jsonList = collections.map((c) => c.toJson()).toList();
-    await _prefs.setString(_collectionsKey, jsonEncode(jsonList));
-  }
-
-  static List<Bookmark> loadAllBookmarks() {
+  static List<Bookmark> loadBookmarks() {
     final jsonString = _prefs.getString(_bookmarksKey) ?? '[]';
     final jsonList = jsonDecode(jsonString) as List;
     return jsonList
@@ -49,42 +35,29 @@ class Storage {
         .toList();
   }
 
-  static Future<void> saveAllBookmarks(List<Bookmark> bookmarks) async {
+  static Future<void> saveCollections(List<Collection> collections) async {
+    final jsonList = collections.map((c) => c.toJson()).toList();
+    await _prefs.setString(_collectionsKey, jsonEncode(jsonList));
+  }
+
+  static Future<void> saveBookmarks(List<Bookmark> bookmarks) async {
     final jsonList = bookmarks.map((b) => b.toJson()).toList();
     await _prefs.setString(_bookmarksKey, jsonEncode(jsonList));
   }
 
   static List<Bookmark> loadBookmarksForCollection(int collectionId) {
-    final allBookmarks = loadAllBookmarks();
+    final allBookmarks = loadBookmarks();
     return allBookmarks.where((b) => b.collectionId == collectionId).toList();
   }
 
   static Future<void> addBookmark(Bookmark bookmark) async {
-    final bookmarks = loadAllBookmarks();
+    final bookmarks = loadBookmarks();
     bookmarks.add(bookmark);
-    await saveAllBookmarks(bookmarks);
-  }
-
-  static Future<void> deleteBookmark(Bookmark bookmark) async {
-    final bookmarks = loadAllBookmarks();
-    bookmarks.remove(bookmark);
-    await saveAllBookmarks(bookmarks);
-  }
-
-  static Future<void> deleteBookmarkById(int bookmarkId) async {
-    final bookmarks = loadAllBookmarks();
-    bookmarks.removeWhere((b) => b.id == bookmarkId);
-    await saveAllBookmarks(bookmarks);
-  }
-
-  static Future<void> deleteBookmarksForCollection(int collectionId) async {
-    final bookmarks = loadAllBookmarks();
-    bookmarks.removeWhere((b) => b.collectionId == collectionId);
-    await saveAllBookmarks(bookmarks);
+    await saveBookmarks(bookmarks);
   }
 
   static Future<void> addOrUpdateBookmark(Bookmark bookmark) async {
-    final bookmarks = loadAllBookmarks();
+    final bookmarks = loadBookmarks();
     final index = bookmarks.indexWhere((b) => b.id == bookmark.id);
 
     if (index == -1) {
@@ -92,7 +65,19 @@ class Storage {
     } else if (index >= 0) {
       bookmarks[index] = bookmark;
     }
-    await saveAllBookmarks(bookmarks);
+    await saveBookmarks(bookmarks);
+  }
+
+  static Future<void> addOrUpdateCollection(Collection collection) async {
+    final collections = loadCollections();
+    final index = collections.indexWhere((b) => b.id == collection.id);
+
+    if (index == -1) {
+      collections.add(collection);
+    } else if (index >= 0) {
+      collections[index] = collection;
+    }
+    await saveCollections(collections);
   }
 
   static Future<void> updateBookmarkById(
@@ -101,7 +86,7 @@ class Storage {
     String? description,
     String? link,
   }) async {
-    final bookmarks = loadAllBookmarks();
+    final bookmarks = loadBookmarks();
     final index = bookmarks.indexWhere((b) => b.id == bookmarkId);
 
     if (index == -1) return;
@@ -110,7 +95,34 @@ class Storage {
     if (description != null) bookmarks[index].description = description;
     if (link != null) bookmarks[index].link = link;
 
-    await saveAllBookmarks(bookmarks);
+    await saveBookmarks(bookmarks);
+  }
+
+  static Future<void> deleteBookmark(Bookmark bookmark) async {
+    final bookmarks = loadBookmarks();
+    bookmarks.remove(bookmark);
+    await saveBookmarks(bookmarks);
+  }
+
+  static Future<void> deleteBookmarkById(int bookmarkId) async {
+    final bookmarks = loadBookmarks();
+    bookmarks.removeWhere((b) => b.id == bookmarkId);
+    await saveBookmarks(bookmarks);
+  }
+
+  static Future<void> deleteBookmarksForCollection(int collectionId) async {
+    final bookmarks = loadBookmarks();
+    bookmarks.removeWhere((b) => b.collectionId == collectionId);
+    await saveBookmarks(bookmarks);
+  }
+
+  static Future<void> deleteCollection(Collection collection) async {
+    final collections = loadCollections();
+    final bookmarks = loadBookmarks();
+    bookmarks.removeWhere((bookmark) => bookmark.collectionId == collection.id);
+    collections.remove(collection);
+    await saveBookmarks(bookmarks);
+    await saveCollections(collections);
   }
 
   static Map<String, int> getStats() {
@@ -124,7 +136,7 @@ class Storage {
 
   static Future<void> updateStats() async {
     final collections = loadCollections();
-    final bookmarks = loadAllBookmarks();
+    final bookmarks = loadBookmarks();
 
     final stats = {
       'totalCollections': collections.length,
@@ -134,4 +146,13 @@ class Storage {
 
     await _prefs.setString(_statsKey, jsonEncode(stats));
   }
+
+  static SharedPreferencesWithCache get _prefs {
+    if (_prefsWithCache == null) {
+      throw StateError(
+        'BookmarkStorage not initialized. Call initialize() first.',
+      );
+    }
+    return _prefsWithCache!;
+  }
 }

lib/service/url_launcher.dart

@@ -1,8 +1,14 @@
 import 'package:url_launcher/url_launcher.dart';
 
-Future<void> launchUrlFromString(String url) async {
-  final Uri uri = Uri.parse(url);
+Future<UrlLaunchErrorCode> launchUrlFromString(String url) async {
+  final Uri? uri = Uri.tryParse(url);
+  final isValid =
+      uri != null && uri.hasAbsolutePath && uri.scheme.startsWith('http');
+  if (!isValid) return UrlLaunchErrorCode.invalidUrl;
   if (!await launchUrl(uri, mode: LaunchMode.externalApplication)) {
-    throw Exception('Could not launch $url');
+    return UrlLaunchErrorCode.couldNotLaunch;
   }
+  return UrlLaunchErrorCode.none;
 }
+
+enum UrlLaunchErrorCode { none, couldNotLaunch, invalidUrl }

lib/widgets/create_bookmark_collection_dialog.dart

@@ -1,18 +1,35 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 
+import '../model/collection.dart';
+import 'edit_dialog_widgets/edit_dialog_actions.dart' show EditDialogActions;
+import 'edit_dialog_widgets/edit_dialog_title.dart';
+
 class CreateBookmarkCollectionDialog extends StatelessWidget {
   const CreateBookmarkCollectionDialog({
     super.key,
     required this.onSavePressed,
+    this.onDeletePressed,
+    this.selectedCollection,
   });
-  final void Function(String name) onSavePressed;
+
+  final void Function()? onDeletePressed;
+  final void Function(Collection collection) onSavePressed;
+  final Collection? selectedCollection;
 
   @override
   Widget build(BuildContext context) {
     final nameController = TextEditingController();
+
+    if (selectedCollection != null) {
+      nameController.text = selectedCollection!.name;
+    }
+
     return AlertDialog(
-      title: Text('Create Collection'),
+      title: EditDialogTitle(
+        dialogType: DialogType.collection,
+        onDeletePressed: onDeletePressed,
+      ),
       content: TextField(
         controller: nameController,
         autofocus: true,
@@ -23,17 +40,20 @@ class CreateBookmarkCollectionDialog extends StatelessWidget {
           FilteringTextInputFormatter.deny(RegExp(r'\s\s+')),
         ],
         decoration: InputDecoration(
+          // TODO: Localize
           labelText: 'Collection Name',
           border: OutlineInputBorder(borderRadius: BorderRadius.circular(10)),
         ),
       ),
       actions: [
-        FloatingActionButton(
-          onPressed: () {
-            onSavePressed(nameController.text);
+        EditDialogActions(
+          onSavePressed: () {
+            final bookmark =
+                selectedCollection?.copyWith(name: nameController.text) ??
+                Collection(name: nameController.text);
+            onSavePressed(bookmark);
             Navigator.of(context).pop();
           },
-          child: Icon(Icons.save),
         ),
       ],
     );

lib/widgets/create_bookmark_dialog.dart

@@ -3,6 +3,8 @@ import 'package:flutter/services.dart';
 
 import '../model/bookmark.dart';
 import '../model/maps_link_metadata.dart';
+import 'edit_dialog_widgets/edit_dialog_actions.dart';
+import 'edit_dialog_widgets/edit_dialog_title.dart';
 
 class CreateBookmarkDialog extends StatelessWidget {
   const CreateBookmarkDialog({
@@ -13,6 +15,7 @@ class CreateBookmarkDialog extends StatelessWidget {
     this.selectedBookmark,
     this.selectedMapsLink,
   });
+
   final void Function(Bookmark bookmark)? onSavePressed;
   final void Function()? onDeletePressed;
   final int collectionId;
@@ -36,7 +39,10 @@ class CreateBookmarkDialog extends StatelessWidget {
     }
 
     return AlertDialog(
-      title: Text('Create Bookmark'),
+      title: EditDialogTitle(
+        dialogType: DialogType.bookmark,
+        onDeletePressed: onDeletePressed,
+      ),
       content: SingleChildScrollView(
         child: Column(
           children: [
@@ -97,41 +103,23 @@ class CreateBookmarkDialog extends StatelessWidget {
         ),
       ),
       actions: [
-        Row(
-          mainAxisAlignment: MainAxisAlignment.spaceBetween,
-          children: [
-            TextButton(
-              onPressed: () => Navigator.of(context).pop(),
-              child: Text('Cancel'),
-            ),
-            FloatingActionButton(
-              onPressed: () {
-                final bookmark =
-                    selectedBookmark?.copyWith(
-                      name: nameController.text,
-                      link: linkController.text,
-                      description: descriptionController.text,
-                    ) ??
-                    Bookmark(
-                      collectionId: collectionId,
-                      name: nameController.text,
-                      link: linkController.text,
-                      description: descriptionController.text,
-                    );
-                onSavePressed?.call(bookmark);
-                Navigator.of(context).pop();
-              },
-              child: Icon(Icons.save),
-            ),
-            if (selectedBookmark != null)
-              TextButton(
-                onPressed: () {
-                  onDeletePressed?.call();
-                  Navigator.of(context).pop();
-                },
-                child: Text('Delete'),
-              ),
-          ],
+        EditDialogActions(
+          onSavePressed: () {
+            final bookmark =
+                selectedBookmark?.copyWith(
+                  name: nameController.text,
+                  link: linkController.text,
+                  description: descriptionController.text,
+                ) ??
+                Bookmark(
+                  collectionId: collectionId,
+                  name: nameController.text,
+                  link: linkController.text,
+                  description: descriptionController.text,
+                );
+            onSavePressed?.call(bookmark);
+            Navigator.of(context).pop();
+          },
         ),
       ],
     );

lib/widgets/edit_dialog_widgets/edit_dialog_actions.dart

@@ -0,0 +1,22 @@
+import 'package:flutter/material.dart'
+    show TextButton, FloatingActionButton, Icons;
+import 'package:flutter/widgets.dart';
+
+class EditDialogActions extends StatelessWidget {
+  const EditDialogActions({super.key, required this.onSavePressed});
+  final VoidCallback onSavePressed;
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      mainAxisAlignment: MainAxisAlignment.spaceBetween,
+      children: [
+        TextButton(
+          onPressed: () => Navigator.of(context).pop(),
+          child: Text('Cancel'),
+        ),
+        FloatingActionButton(onPressed: onSavePressed, child: Icon(Icons.save)),
+      ],
+    );
+  }
+}

lib/widgets/edit_dialog_widgets/edit_dialog_title.dart

@@ -0,0 +1,40 @@
+import 'package:flutter/material.dart' show TextButton, Theme;
+import 'package:flutter/widgets.dart';
+
+class EditDialogTitle extends StatelessWidget {
+  const EditDialogTitle({
+    super.key,
+    this.onDeletePressed,
+    required this.dialogType,
+  });
+  final VoidCallback? onDeletePressed;
+  final DialogType dialogType;
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      mainAxisAlignment: MainAxisAlignment.spaceBetween,
+      children: [
+        // TODO: Localize
+        if (dialogType == DialogType.bookmark)
+          Text('Create Bookmark')
+        else
+          Text('Create Collection'),
+
+        if (onDeletePressed != null)
+          TextButton(
+            onPressed: () {
+              onDeletePressed!.call();
+              Navigator.of(context).pop();
+            },
+            child: Text(
+              'Delete',
+              style: TextStyle(color: Theme.of(context).colorScheme.error),
+            ),
+          ),
+      ],
+    );
+  }
+}
+
+enum DialogType { bookmark, collection }