feat: [BoardEditor] add reset board and starting position option

lib/src/model/board_editor/board_editor_controller.dart

@@ -64,8 +64,25 @@ class BoardEditorController extends _$BoardEditorController {
     );
   }
 
-  void loadFen(String fen) {
-    _updatePosition(readFen(fen).lock);
+  void loadFen(
+    String fen, {
+    bool loadSideToPlay = false,
+    bool loadCastling = false,
+  }) {
+    final splits = fen.split(' ');
+    _updatePosition(readFen(splits[0]).lock);
+
+    if (loadSideToPlay && splits.length >= 2) {
+      setSideToPlay(splits[1].toLowerCase() == 'w' ? Side.white : Side.black);
+    }
+
+    if (loadCastling && splits.length >= 3) {
+      final castling = splits[2];
+      setCastling(Side.white, CastlingSide.king, castling.contains('K'));
+      setCastling(Side.white, CastlingSide.queen, castling.contains('Q'));
+      setCastling(Side.black, CastlingSide.king, castling.contains('k'));
+      setCastling(Side.black, CastlingSide.queen, castling.contains('q'));
+    }
   }
 
   /// Calculates the squares where an en passant capture could be possible.

lib/src/view/board_editor/board_editor_screen.dart

@@ -14,10 +14,12 @@ import 'package:lichess_mobile/src/utils/navigation.dart';
 import 'package:lichess_mobile/src/utils/screen.dart';
 import 'package:lichess_mobile/src/utils/share.dart';
 import 'package:lichess_mobile/src/view/analysis/analysis_screen.dart';
-import 'package:lichess_mobile/src/view/board_editor/board_editor_menu.dart';
+import 'package:lichess_mobile/src/view/board_editor/board_editor_settings.dart';
+import 'package:lichess_mobile/src/widgets/adaptive_action_sheet.dart';
 import 'package:lichess_mobile/src/widgets/adaptive_bottom_sheet.dart';
 import 'package:lichess_mobile/src/widgets/bottom_bar.dart';
 import 'package:lichess_mobile/src/widgets/bottom_bar_button.dart';
+import 'package:lichess_mobile/src/widgets/buttons.dart';
 import 'package:lichess_mobile/src/widgets/platform_scaffold.dart';
 
 class BoardEditorScreen extends StatelessWidget {
@@ -30,6 +32,21 @@ class BoardEditorScreen extends StatelessWidget {
     return PlatformScaffold(
       appBar: PlatformAppBar(
         title: Text(context.l10n.boardEditor),
+        actions: [
+          AppBarIconButton(
+            onPressed: () => showAdaptiveBottomSheet<void>(
+              context: context,
+              isScrollControlled: true,
+              showDragHandle: true,
+              isDismissible: true,
+              builder: (context) => BoardEditorPositionSettings(
+                initialFen: initialFen,
+              ),
+            ),
+            semanticsLabel: context.l10n.settingsSettings,
+            icon: const Icon(Icons.settings),
+          ),
+        ],
       ),
       body: _Body(initialFen),
     );
@@ -306,21 +323,39 @@ class _BottomBar extends ConsumerWidget {
       children: [
         BottomBarButton(
           label: context.l10n.menu,
-          onTap: () => showAdaptiveBottomSheet<void>(
-            context: context,
-            builder: (BuildContext context) => BoardEditorMenu(
-              initialFen: initialFen,
-            ),
-          ),
-          icon: Icons.tune,
-        ),
-        BottomBarButton(
-          key: const Key('flip-button'),
-          label: context.l10n.flipBoard,
-          onTap: ref
-              .read(boardEditorControllerProvider(initialFen).notifier)
-              .flipBoard,
-          icon: CupertinoIcons.arrow_2_squarepath,
+          key: const Key('board-editor-menu-button'),
+          onTap: () {
+            final editorProviderData =
+                ref.read(boardEditorControllerProvider(initialFen).notifier);
+            showAdaptiveActionSheet<void>(
+              context: context,
+              actions: [
+                BottomSheetAction(
+                  makeLabel: (context) => Text(context.l10n.startPosition),
+                  onPressed: (context) {
+                    editorProviderData.loadFen(
+                      kInitialFEN,
+                      loadCastling: true,
+                      loadSideToPlay: true,
+                    );
+                  },
+                ),
+                BottomSheetAction(
+                  makeLabel: (context) => Text(context.l10n.clearBoard),
+                  onPressed: (context) {
+                    editorProviderData.loadFen(kEmptyBoardFEN);
+                  },
+                ),
+                BottomSheetAction(
+                  makeLabel: (context) => Text(context.l10n.flipBoard),
+                  onPressed: (context) {
+                    editorProviderData.flipBoard();
+                  },
+                ),
+              ],
+            );
+          },
+          icon: Icons.menu,
         ),
         BottomBarButton(
           label: context.l10n.analysis,

lib/src/view/board_editor/board_editor_menu.dart → lib/src/view/board_editor/board_editor_settings.dart

@@ -6,8 +6,8 @@ import 'package:lichess_mobile/src/styles/styles.dart';
 import 'package:lichess_mobile/src/utils/l10n_context.dart';
 import 'package:lichess_mobile/src/widgets/adaptive_bottom_sheet.dart';
 
-class BoardEditorMenu extends ConsumerWidget {
-  const BoardEditorMenu({required this.initialFen, super.key});
+class BoardEditorPositionSettings extends ConsumerWidget {
+  const BoardEditorPositionSettings({required this.initialFen, super.key});
 
   final String? initialFen;
 

test/view/board_editor/board_editor_screen_test.dart

@@ -36,24 +36,62 @@ void main() {
       );
     });
 
-    testWidgets('Flip board', (tester) async {
-      final app = await buildTestApp(
-        tester,
-        home: const BoardEditorScreen(),
-      );
-      await tester.pumpWidget(app);
-
-      await tester.tap(find.byKey(const Key('flip-button')));
-      await tester.pump();
-
-      expect(
-        tester
-            .widget<ChessboardEditor>(
-              find.byType(ChessboardEditor),
-            )
-            .orientation,
-        Side.black,
-      );
+    group('Board editor menu', () {
+      Future<void> loadWidgetAndOpenMenu(WidgetTester tester) async {
+        final app = await buildTestApp(
+          tester,
+          home: const BoardEditorScreen(),
+        );
+        await tester.pumpWidget(app);
+
+        await tester.tap(find.byKey(const Key('board-editor-menu-button')));
+        await tester.pump();
+      }
+
+      testWidgets('Flip board', (tester) async {
+        await loadWidgetAndOpenMenu(tester);
+        await tester.tap(find.text('Flip board'));
+        await tester.pump();
+
+        expect(
+          tester
+              .widget<ChessboardEditor>(
+                find.byType(ChessboardEditor),
+              )
+              .orientation,
+          Side.black,
+        );
+      });
+
+      testWidgets('Reset to Starting Position', (tester) async {
+        await loadWidgetAndOpenMenu(tester);
+        await tester.tap(find.text('Starting position'));
+        await tester.pump();
+
+        expect(
+          tester
+              .widget<ChessboardEditor>(
+                find.byType(ChessboardEditor),
+              )
+              .pieces,
+          readFen(kInitialFEN),
+        );
+      });
+
+      testWidgets('Clear board', (tester) async {
+        await loadWidgetAndOpenMenu(tester);
+        await tester.tap(find.text('Clear board'));
+        await tester.pump();
+
+        expect(
+          tester
+              .widget<ChessboardEditor>(
+                find.byType(ChessboardEditor),
+              )
+              .pieces,
+          readFen(kEmptyBoardFEN),
+        );
+      });
     });
 
     testWidgets('Side to play and castling rights', (tester) async {
@@ -63,7 +101,6 @@ void main() {
       );
       await tester.pumpWidget(app);
 
-      await tester.tap(find.byKey(const Key('flip-button')));
       await tester.pump();
 
       final container = ProviderScope.containerOf(