feat: added alien bumpers zone to game

lib/game/components/alien_zone.dart

@@ -0,0 +1,90 @@
+// ignore_for_file: avoid_renaming_method_parameters
+
+import 'package:flame/components.dart';
+import 'package:flame_bloc/flame_bloc.dart';
+import 'package:flame_forge2d/flame_forge2d.dart';
+import 'package:flutter/material.dart';
+import 'package:pinball/flame/flame.dart';
+import 'package:pinball/game/game.dart';
+import 'package:pinball_components/pinball_components.dart';
+
+/// {@template alien_zone}
+/// Area positioned below [Spaceship] where the [Ball]
+/// can bounce off [AlienBumper]s.
+///
+/// When a [Ball] hits [AlienBumper]s, they toggle between activated and
+/// deactivated states.
+/// {@endtemplate}
+class AlienZone extends Component with HasGameRef<PinballGame> {
+  /// {@macro alien_zone}
+  AlienZone();
+
+  @override
+  Future<void> onLoad() async {
+    await super.onLoad();
+
+    gameRef.addContactCallback(_ControlledAlienBumperBallContactCallback());
+
+    final lowerLeftBumper = _ControlledAlienBumper.a()
+      ..initialPosition = Vector2(-31, 10);
+    final upperLeftBumper = _ControlledAlienBumper.b()
+      ..initialPosition = Vector2(-22, 17);
+
+    await addAll([
+      lowerLeftBumper,
+      upperLeftBumper,
+    ]);
+  }
+}
+
+class _ControlledAlienBumper extends AlienBumper
+    with Controls<AlienBumperController>, ScorePoints {
+  _ControlledAlienBumper.a() : super.a() {
+    controller = AlienBumperController(this);
+  }
+
+  _ControlledAlienBumper.b() : super.b() {
+    controller = AlienBumperController(this);
+  }
+
+  @override
+  // TODO(ruimiguel): change points when get final points map.
+  int get points => 10;
+}
+
+/// {@template alien_bumper_controller}
+/// Controls a [AlienBumper].
+/// {@endtemplate}
+class AlienBumperController extends ComponentController<AlienBumper>
+    with HasGameRef<PinballGame> {
+  /// {@macro alien_bumper_controller}
+  AlienBumperController(AlienBumper alienBumper) : super(alienBumper);
+
+  /// Flag for activated state of the [AlienBumper].
+  ///
+  /// Used to toggle [AlienBumper]s' state between activated and deactivated.
+  bool isActivated = false;
+
+  /// Registers when a [AlienBumper] is hit by a [Ball].
+  void hit() {
+    if (isActivated) {
+      component.deactivate();
+    } else {
+      component.activate();
+    }
+    isActivated = !isActivated;
+  }
+}
+
+/// Listens when a [Ball] bounces bounces against a [SparkyBumper].
+class _ControlledAlienBumperBallContactCallback
+    extends ContactCallback<Controls<AlienBumperController>, Ball> {
+  @override
+  void begin(
+    Controls<AlienBumperController> controlledAlienBumper,
+    Ball _,
+    Contact __,
+  ) {
+    controlledAlienBumper.controller.hit();
+  }
+}

lib/game/components/board.dart

@@ -15,6 +15,7 @@ class Board extends Component {
     final bottomGroup = _BottomGroup();
 
     final flutterForest = FlutterForest();
+    final alienZone = AlienZone();
 
     // TODO(alestiago): adjust positioning to real design.
     final dino = ChromeDino()
@@ -27,6 +28,7 @@ class Board extends Component {
       bottomGroup,
       dino,
       flutterForest,
+      alienZone,
     ]);
   }
 }

lib/game/components/components.dart

@@ -1,3 +1,4 @@
+export 'alien_zone.dart';
 export 'board.dart';
 export 'bonus_word.dart';
 export 'controlled_ball.dart';