refactor: multipliers cubit

lib/game/components/multipliers/behaviors/behaviors.dart

@@ -0,0 +1 @@
+export 'multipliers_behavior.dart';

lib/game/components/multipliers/behaviors/multipliers_behavior.dart

@@ -0,0 +1,26 @@
+import 'package:flame/components.dart';
+import 'package:pinball/game/game.dart';
+import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_flame/pinball_flame.dart';
+
+/// Toggle each [Multiplier] when GameState.multiplier changes.
+class MultipliersBehavior extends Component
+    with HasGameRef<PinballGame>, ParentIsA<Multipliers> {
+  @override
+  void onMount() {
+    super.onMount();
+
+    // TODO(ruimiguel): filter only when multiplier has change, not every other
+    // state.
+    gameRef.read<GameBloc>().stream.listen((state) {
+      final multipliers = parent.children.whereType<Multiplier>();
+      for (final multiplier in multipliers) {
+        // TODO(ruimiguel): use here GameState.multiplier when merged
+        // https://github.com/VGVentures/pinball/pull/213.
+        final currentMultiplier = state.score.bitLength % 6 + 1;
+
+        multiplier.bloc.toggle(currentMultiplier);
+      }
+    });
+  }
+}

lib/game/components/multipliers/multipliers.dart

@@ -0,0 +1,43 @@
+// ignore_for_file: public_member_api_docs
+
+import 'dart:math' as math;
+import 'package:flame/components.dart';
+import 'package:pinball/game/components/multipliers/behaviors/behaviors.dart';
+import 'package:pinball_components/pinball_components.dart';
+
+/// {@template multipliers_component}
+/// A group for the multipliers over the board.
+/// {@endtemplate}
+class Multipliers extends Component {
+  /// {@macro multipliers_component}
+  Multipliers()
+      : super(
+          children: [
+            Multiplier(
+              value: MultiplierValue.x2,
+              position: Vector2(-19.5, -2),
+              rotation: -15 * math.pi / 180,
+            ),
+            Multiplier(
+              value: MultiplierValue.x3,
+              position: Vector2(13, -9.4),
+              rotation: 15 * math.pi / 180,
+            ),
+            Multiplier(
+              value: MultiplierValue.x4,
+              position: Vector2(0, -21.2),
+            ),
+            Multiplier(
+              value: MultiplierValue.x5,
+              position: Vector2(-8.5, -28),
+              rotation: -3 * math.pi / 180,
+            ),
+            Multiplier(
+              value: MultiplierValue.x6,
+              position: Vector2(10, -30.7),
+              rotation: 8 * math.pi / 180,
+            ),
+            MultipliersBehavior(),
+          ],
+        );
+}

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

@@ -19,7 +19,7 @@ export 'kicker.dart';
 export 'launch_ramp.dart';
 export 'layer.dart';
 export 'layer_sensor.dart';
-export 'multiplier.dart';
+export 'multiplier/multiplier.dart';
 export 'plunger.dart';
 export 'render_priority.dart';
 export 'rocket.dart';

packages/pinball_components/lib/src/components/multiplier/cubit/multiplier_cubit.dart

@@ -0,0 +1,47 @@
+// ignore_for_file: public_member_api_docs
+
+import 'package:bloc/bloc.dart';
+import 'package:equatable/equatable.dart';
+import 'package:pinball_components/pinball_components.dart';
+
+part 'multiplier_state.dart';
+
+class MultiplierCubit extends Cubit<MultiplierState> {
+  MultiplierCubit(MultiplierValue multiplierValue)
+      : super(
+          MultiplierState(
+            value: multiplierValue,
+            spriteState: MultiplierSpriteState.dimmed,
+          ),
+        );
+
+  /// Event added when the game current multiplier changes.
+  void toggle(int multiplier) {
+    if (state.equalsTo(multiplier)) {
+      if (state.spriteState == MultiplierSpriteState.dimmed) {
+        emit(state.copyWith(spriteState: MultiplierSpriteState.lit));
+      }
+    } else {
+      if (state.spriteState == MultiplierSpriteState.lit) {
+        emit(state.copyWith(spriteState: MultiplierSpriteState.dimmed));
+      }
+    }
+  }
+}
+
+extension on MultiplierState {
+  bool equalsTo(int value) {
+    switch (this.value) {
+      case MultiplierValue.x2:
+        return value == 2;
+      case MultiplierValue.x3:
+        return value == 3;
+      case MultiplierValue.x4:
+        return value == 4;
+      case MultiplierValue.x5:
+        return value == 5;
+      case MultiplierValue.x6:
+        return value == 6;
+    }
+  }
+}

packages/pinball_components/lib/src/components/multiplier/cubit/multiplier_state.dart

@@ -0,0 +1,35 @@
+// ignore_for_file: public_member_api_docs
+
+part of 'multiplier_cubit.dart';
+
+/// Indicates the different sprite states for [MultiplierSpriteGroupComponent].
+enum MultiplierSpriteState {
+  lit,
+  dimmed,
+}
+
+/// Indicates the [MultiplierCubit]'s current state.
+class MultiplierState extends Equatable {
+  const MultiplierState({
+    required this.value,
+    required this.spriteState,
+  });
+
+  /// Current value for the [Multiplier]
+  final MultiplierValue value;
+
+  /// The [MultiplierSpriteGroupComponent] current sprite state
+  final MultiplierSpriteState spriteState;
+
+  MultiplierState copyWith({
+    MultiplierSpriteState? spriteState,
+  }) {
+    return MultiplierState(
+      value: value,
+      spriteState: spriteState ?? this.spriteState,
+    );
+  }
+
+  @override
+  List<Object> get props => [value, spriteState];
+}

packages/pinball_components/lib/src/components/multiplier/multiplier.dart

@@ -3,6 +3,10 @@
 import 'package:flame/components.dart';
 import 'package:flutter/material.dart';
 import 'package:pinball_components/gen/assets.gen.dart';
+import 'package:pinball_components/src/components/multiplier/cubit/multiplier_cubit.dart';
+import 'package:pinball_flame/pinball_flame.dart';
+
+export 'cubit/multiplier_cubit.dart';
 
 /// {@template multiplier}
 /// A [Component] for the multiplier over the board.
@@ -14,29 +18,50 @@ class Multiplier extends Component {
     required Vector2 position,
     double rotation = 0,
   })  : _value = value,
-        _sprite = MultiplierSpriteGroupComponent(
-          position: position,
-          litAssetPath: value.litAssetPath,
-          dimmedAssetPath: value.dimmedAssetPath,
-          rotation: rotation,
-        );
+        _position = position,
+        _rotation = rotation,
+        bloc = MultiplierCubit(value),
+        super();
 
   final MultiplierValue _value;
-  final MultiplierSpriteGroupComponent _sprite;
+  final Vector2 _position;
+  final double _rotation;
+  late final MultiplierSpriteGroupComponent _sprite;
+
+  /// Creates a [Multiplier] without any children.
+  ///
+  /// This can be used for testing [Multiplier]'s behaviors in isolation.
+  // TODO(alestiago): Refactor injecting bloc once the following is merged:
+  // https://github.com/flame-engine/flame/pull/1538
+  @visibleForTesting
+  Multiplier.test({
+    required MultiplierValue value,
+    required this.bloc,
+  })  : _value = value,
+        _position = Vector2.zero(),
+        _rotation = 0;
 
-  /// Change current [Sprite] to active or inactive depending on applied
-  /// multiplier.
-  void toggle(int multiplier) {
-    if (_value.equalsTo(multiplier)) {
-      _sprite.current = MultiplierSpriteState.lit;
-    } else {
-      _sprite.current = MultiplierSpriteState.dimmed;
-    }
+// TODO(ruimiguel): Consider refactoring once the following is merged:
+  // https://github.com/flame-engine/flame/pull/1538
+  // ignore: public_member_api_docs
+  final MultiplierCubit bloc;
+
+  @override
+  void onRemove() {
+    bloc.close();
+    super.onRemove();
   }
 
   @override
   Future<void> onLoad() async {
     await super.onLoad();
+    _sprite = MultiplierSpriteGroupComponent(
+      position: _position,
+      litAssetPath: _value.litAssetPath,
+      dimmedAssetPath: _value.dimmedAssetPath,
+      rotation: _rotation,
+      current: bloc.state,
+    );
     await add(_sprite);
   }
 }
@@ -50,15 +75,6 @@ enum MultiplierValue {
   x6,
 }
 
-/// Indicates the current sprite state of the multiplier.
-enum MultiplierSpriteState {
-  /// A lit up bumper.
-  lit,
-
-  /// A dimmed bumper.
-  dimmed,
-}
-
 extension on MultiplierValue {
   String get litAssetPath {
     switch (this) {
@@ -89,21 +105,6 @@ extension on MultiplierValue {
         return Assets.images.multiplier.x6.dimmed.keyName;
     }
   }
-
-  bool equalsTo(int value) {
-    switch (this) {
-      case MultiplierValue.x2:
-        return value == 2;
-      case MultiplierValue.x3:
-        return value == 3;
-      case MultiplierValue.x4:
-        return value == 4;
-      case MultiplierValue.x5:
-        return value == 5;
-      case MultiplierValue.x6:
-        return value == 6;
-    }
-  }
 }
 
 /// {@template multiplier_sprite_group_component}
@@ -111,19 +112,22 @@ extension on MultiplierValue {
 /// {@endtemplate}
 @visibleForTesting
 class MultiplierSpriteGroupComponent
-    extends SpriteGroupComponent<MultiplierSpriteState> with HasGameRef {
+    extends SpriteGroupComponent<MultiplierSpriteState>
+    with HasGameRef, ParentIsA<Multiplier> {
   /// {@macro multiplier_sprite_group_component}
   MultiplierSpriteGroupComponent({
     required Vector2 position,
     required String litAssetPath,
     required String dimmedAssetPath,
     required double rotation,
+    required MultiplierState current,
   })  : _litAssetPath = litAssetPath,
         _dimmedAssetPath = dimmedAssetPath,
         super(
           anchor: Anchor.center,
           position: position,
           angle: rotation,
+          current: current.spriteState,
         );
 
   final String _litAssetPath;
@@ -132,6 +136,7 @@ class MultiplierSpriteGroupComponent
   @override
   Future<void> onLoad() async {
     await super.onLoad();
+    parent.bloc.stream.listen((state) => current = state.spriteState);
 
     final sprites = {
       MultiplierSpriteState.lit:
@@ -140,8 +145,6 @@ class MultiplierSpriteGroupComponent
           Sprite(gameRef.images.fromCache(_dimmedAssetPath)),
     };
     this.sprites = sprites;
-
-    current = MultiplierSpriteState.dimmed;
     size = sprites[current]!.originalSize / 10;
   }
 }