feat: finishing contrls

packages/pinball_components/lib/src/components/backboard/backboard_game_over.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:math';
 
 import 'package:flame/components.dart';
 import 'package:flutter/material.dart';
@@ -10,8 +11,7 @@ import 'package:pinball_components/pinball_components.dart';
 /// [PositionComponent] that handles the user input on the
 /// game over display view.
 /// {@endtemplate}
-class BackboardGameOver extends PositionComponent
-    with HasGameRef, KeyboardHandler {
+class BackboardGameOver extends PositionComponent with HasGameRef {
   /// {@macro backboard_game_over}
   BackboardGameOver({
     required int score,
@@ -76,12 +76,29 @@ class BackboardGameOver extends PositionComponent
         ),
       );
     }
+
+    unawaited(
+      add(
+        KeyboardInputController(
+          keyUp: {
+            LogicalKeyboardKey.arrowLeft: () => _movePrompt(true),
+            LogicalKeyboardKey.arrowRight: () => _movePrompt(false),
+          },
+        ),
+      ),
+    );
   }
 
-  @override
-  bool onKeyEvent(RawKeyEvent event, Set<LogicalKeyboardKey> keysPressed) {
-    final isUp = event is RawKeyUpEvent;
+  bool _movePrompt(bool left) {
+    final prompts = children.whereType<BackboardLetterPrompt>().toList();
+
+    final current = prompts.firstWhere((prompt) => prompt.hasFocus)
+      ..hasFocus = false;
+    var index = prompts.indexOf(current) + (left ? -1 : 1);
+    index = min(max(0, index), prompts.length - 1);
+
+    prompts[index].hasFocus = true;
 
-    return true;
+    return false;
   }
 }

packages/pinball_components/lib/src/components/backboard/backboard_letter_prompt.dart

@@ -1,8 +1,9 @@
 import 'dart:async';
-import 'dart:ui';
+import 'dart:math';
 
 import 'package:flame/components.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 import 'package:pinball_components/pinball_components.dart';
 
 /// {@template backboard_letter_prompt}
@@ -20,10 +21,10 @@ class BackboardLetterPrompt extends PositionComponent {
         );
 
   static const _alphabetCode = 65;
-  static const _alphabetLength = 26;
+  static const _alphabetLength = 25;
+  var _charIndex = 0;
 
   bool _hasFocus;
-  String _char = '';
 
   late RectangleComponent _underscore;
   late TextComponent _input;
@@ -43,9 +44,9 @@ class BackboardLetterPrompt extends PositionComponent {
     unawaited(add(_underscore));
 
     _input = TextComponent(
-        text: _hasFocus ? 'A' : '',
-        textRenderer: Backboard.textPaint,
-        anchor: Anchor.center,
+      text: 'A',
+      textRenderer: Backboard.textPaint,
+      anchor: Anchor.center,
     );
     unawaited(add(_input));
 
@@ -61,14 +62,42 @@ class BackboardLetterPrompt extends PositionComponent {
     );
 
     unawaited(add(_underscoreBlinker));
-  }
 
-  void up() {
+    unawaited(
+      add(
+        KeyboardInputController(
+          keyUp: {
+            LogicalKeyboardKey.arrowUp: () => _cycle(true),
+            LogicalKeyboardKey.arrowDown: () => _cycle(false),
+          },
+        ),
+      ),
+    );
   }
 
-  void down() {
+  bool _cycle(bool up) {
+    if (_hasFocus) {
+      final newCharCode =
+          min(max(_charIndex + (up ? 1 : -1), 0), _alphabetLength);
+      _input.text = String.fromCharCode(_alphabetCode + newCharCode);
+      _charIndex = newCharCode;
+
+      return false;
+    }
+    return true;
   }
 
-  void nextPrompt() {
+  /// Returns if this prompt has focus on it
+  bool get hasFocus => _hasFocus;
+
+  /// Updates this prompt focus
+  set hasFocus(bool hasFocus) {
+    if (hasFocus) {
+      _underscoreBlinker.timer.resume();
+    } else {
+      _underscoreBlinker.timer.pause();
+    }
+    _underscore.paint.color = Colors.white;
+    _hasFocus = hasFocus;
   }
 }

packages/pinball_components/lib/src/flame/flame.dart

@@ -1,2 +1,3 @@
 export 'blueprint.dart';
+export 'keyboard_input_controller.dart';
 export 'priority.dart';

packages/pinball_components/lib/src/flame/keyboard_input_controller.dart

@@ -0,0 +1,36 @@
+import 'package:flame/components.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+/// The signature for a key handle function
+typedef KeyHandlerCallback = bool Function();
+
+/// {@template keyboard_input_controller}
+/// A that receives keyboard input and execute registered methods
+/// {@endtemplate}
+class KeyboardInputController extends Component with KeyboardHandler {
+
+  /// {@macro keyboard_input_controller}
+  KeyboardInputController({
+    Map<LogicalKeyboardKey, KeyHandlerCallback> keyUp = const {},
+    Map<LogicalKeyboardKey, KeyHandlerCallback> keyDown = const {},
+  }) : _keyUp = keyUp,
+     _keyDown = keyDown;
+
+  final Map<LogicalKeyboardKey, KeyHandlerCallback> _keyUp;
+  final Map<LogicalKeyboardKey, KeyHandlerCallback> _keyDown;
+
+  @override
+  bool onKeyEvent(RawKeyEvent event, Set<LogicalKeyboardKey> keysPressed) {
+    final isUp = event is RawKeyUpEvent;
+
+    final handlers = isUp ? _keyUp : _keyDown;
+    final handler = handlers[event.logicalKey];
+
+    if (handler != null) {
+      return handler();
+    }
+
+    return true;
+  }
+}