Add support for vim keymap and emulation

pkgs/dartpad_ui/lib/editor/codemirror.dart

@@ -50,6 +50,9 @@ extension type CodeMirror._(JSObject _) implements JSObject {
   String getTheme() => (getOption('theme') as JSString).toDart;
   void setTheme(String theme) => setOption('theme', theme.toJS);
 
+  String getKeymap() => (getOption('keyMap') as JSString).toDart;
+  void setKeymap(String keyMap) => setOption('keyMap', keyMap.toJS);
+
   external void scrollTo(num? x, num? y);
   external ScrollInfo getScrollInfo();
 

pkgs/dartpad_ui/lib/editor/editor.dart

@@ -236,6 +236,7 @@ class _EditorWidgetState extends State<EditorWidget> implements EditorService {
     appModel.sourceCodeController.addListener(_updateCodemirrorFromModel);
     appModel.analysisIssues
         .addListener(() => _updateIssues(appModel.analysisIssues.value));
+    appModel.vimKeymapsEnabled.addListener(_updateCodemirrorKeymap);
 
     widget.appServices.registerEditorService(this);
 
@@ -317,6 +318,7 @@ class _EditorWidgetState extends State<EditorWidget> implements EditorService {
     widget.appModel.sourceCodeController
         .removeListener(_updateCodemirrorFromModel);
     widget.appModel.appReady.removeListener(_updateEditableStatus);
+    widget.appModel.vimKeymapsEnabled.removeListener(_updateCodemirrorKeymap);
 
     super.dispose();
   }
@@ -432,6 +434,17 @@ class _EditorWidgetState extends State<EditorWidget> implements EditorService {
       );
     }
   }
+
+  void _updateCodemirrorKeymap() {
+    final enabled = widget.appModel.vimKeymapsEnabled.value;
+    final cm = codeMirror!;
+
+    if (enabled) {
+      cm.setKeymap('vim');
+    } else {
+      cm.setKeymap('default');
+    }
+  }
 }
 
 // codemirror commands

pkgs/dartpad_ui/lib/main.dart

@@ -830,7 +830,10 @@ class StatusLineWidget extends StatelessWidget {
                 builder: (context) => MediumDialog(
                   title: 'Keyboard shortcuts',
                   smaller: true,
-                  child: KeyBindingsTable(bindings: keys.keyBindings),
+                  child: KeyBindingsTable(
+                    bindings: keys.keyBindings,
+                    appModel: appModel,
+                  ),
                 ),
               ),
               child: Icon(
@@ -1156,9 +1159,11 @@ class ContinueInMenu extends StatelessWidget {
 
 class KeyBindingsTable extends StatelessWidget {
   final List<(String, List<ShortcutActivator>)> bindings;
+  final AppModel appModel;
 
   const KeyBindingsTable({
     required this.bindings,
+    required this.appModel,
     super.key,
   });
 
@@ -1209,6 +1214,10 @@ class KeyBindingsTable extends StatelessWidget {
             ],
           ),
         ),
+        const Divider(),
+        _VimModeSwitch(
+          appModel: appModel,
+        ),
       ],
     );
   }
@@ -1282,6 +1291,32 @@ class _BrightnessButton extends StatelessWidget {
   }
 }
 
+class _VimModeSwitch extends StatelessWidget {
+  final AppModel appModel;
+
+  const _VimModeSwitch({
+    required this.appModel,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return ValueListenableBuilder(
+      valueListenable: appModel.vimKeymapsEnabled,
+      builder: (BuildContext context, bool value, Widget? child) {
+        return SwitchListTile(
+          value: value,
+          title: const Text('Use Vim Key Bindings'),
+          onChanged: _handleToggle,
+        );
+      },
+    );
+  }
+
+  void _handleToggle(bool value) {
+    appModel.vimKeymapsEnabled.value = value;
+  }
+}
+
 extension MenuControllerToggleMenu on MenuController {
   void toggleMenuState() {
     if (isOpen) {

pkgs/dartpad_ui/lib/model.dart

@@ -75,6 +75,8 @@ class AppModel {
   final SplitDragStateManager splitDragStateManager = SplitDragStateManager();
   late final StreamSubscription<SplitDragState> _splitSubscription;
 
+  final ValueNotifier<bool> vimKeymapsEnabled = ValueNotifier(false);
+
   AppModel() {
     consoleOutput.addListener(_recalcLayout);