feat: support new brightness controls

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+  "cSpell.words": ["powerable", "Powerable"]
+}

bin/main.dart

@@ -1,9 +1,9 @@
 import 'dart:math';
 
-import 'package:christmas_lights_kata/grid.dart';
+import 'package:christmas_lights_kata/grid/powerable_grid.dart';
 
 void main(List<String> arguments) {
-  final grid = Grid(1000)
+  final grid = PowerableGrid(1000)
     ..turnOn(const Point(887, 9), const Point(959, 629))
     ..turnOn(const Point(454, 398), const Point(844, 448))
     ..turnOff(const Point(539, 243), const Point(559, 965))

lib/grid/dimmable_grid.dart

@@ -0,0 +1,8 @@
+import 'package:christmas_lights_kata/grid/grid.dart';
+import 'package:christmas_lights_kata/led/dimmable_led.dart';
+
+/// A grid of dimmable LEDs.
+class DimmableGrid extends Grid<DimmableLed> {
+  /// Creates a new [Grid] of [DimmableLed]s.
+  DimmableGrid(int size) : super(size, DimmableLed.new);
+}

lib/grid.dart → lib/grid/grid.dart

@@ -1,21 +1,22 @@
 import 'dart:math';
 
-import 'package:christmas_lights_kata/led.dart';
+import 'package:christmas_lights_kata/led/led.dart';
 
 /// A squared grid of LEDs.
-class Grid {
+class Grid<T extends Led<dynamic>> {
   /// Constructs a new [Grid] from [size].
-  Grid(this.size)
-      : assert(size > 0, 'Size must be positive'),
+  Grid(this.size, T Function() constructor)
+      : assert(size > 0, '"size" must be positive'),
         leds = [
-          for (var x = 0; x < size; x++) [for (var y = 0; y < size; y++) Led()],
+          for (var x = 0; x < size; x++)
+            [for (var y = 0; y < size; y++) constructor()],
         ];
 
   /// The size of this [Grid].
   final int size;
 
   /// The two-dimensional matrix of [Led]s.
-  late final List<List<Led>> leds;
+  final List<List<T>> leds;
 
   /// Turns on all [Led]s from [start] to [end] positions.
   void turnOn(Point<int> start, Point<int> end) =>
@@ -32,7 +33,7 @@ class Grid {
   void _actOnLedsFrom(
     Point<int> start,
     Point<int> end,
-    void Function(Led led) action,
+    void Function(Led<dynamic> led) action,
   ) {
     for (var x = start.x; x <= end.x; x++) {
       for (var y = start.y; y <= end.y; y++) {
@@ -41,12 +42,6 @@ class Grid {
     }
   }
 
-  /// Returns the number of powered [Led]s in the [Grid].
-  int get poweredLedsCount => leds.fold<int>(
-        0,
-        (count, row) => count + row.where((led) => led.isPowered).length,
-      );
-
   @override
   String toString() => leds.map((row) => row.join()).join('\n');
 }

lib/grid/powerable_grid.dart

@@ -0,0 +1,14 @@
+import 'package:christmas_lights_kata/grid/grid.dart';
+import 'package:christmas_lights_kata/led/powerable_led.dart';
+
+/// A grid of powerable LEDs.
+class PowerableGrid extends Grid<PowerableLed> {
+  /// Creates a new [Grid] of [PowerableLed]s.
+  PowerableGrid(int size) : super(size, PowerableLed.new);
+
+  /// Returns the number of powered [PowerableLed]s in the [Grid].
+  int get poweredLedsCount => leds.fold<int>(
+        0,
+        (count, row) => count + row.where((led) => led.isPowered).length,
+      );
+}

lib/led/dimmable_led.dart

@@ -0,0 +1,40 @@
+import 'package:christmas_lights_kata/led/led.dart';
+import 'package:christmas_lights_kata/utils/map_int_v_extension.dart';
+
+const _offLight = '⚫️';
+const _brightnessLights = {
+  0: _offLight,
+  1: '🔅',
+  10: '🔆',
+};
+
+/// A dimmable LED.
+class DimmableLed extends Led<int> {
+  /// Constructs a new [DimmableLed].
+  DimmableLed() : _brightness = 0;
+
+  int _brightness;
+
+  /// Whether this [DimmableLed] is turned on or off.
+  int get brightness => _brightness;
+
+  /// Increases the brightness of this [DimmableLed] by 1.
+  @override
+  int turnOn() => _brightness++;
+
+  /// Reduces the brightness of this [DimmableLed] by 1.
+  @override
+  int turnOff() {
+    if (_brightness > 0) _brightness--;
+
+    return _brightness;
+  }
+
+  /// Increases the brightness of this [DimmableLed] by 2.
+  @override
+  int toggle() => _brightness = _brightness + 2;
+
+  @override
+  String toString() =>
+      _brightnessLights.valueFromThreshold(_brightness) ?? _offLight;
+}

lib/led/led.dart

@@ -0,0 +1,11 @@
+/// An LED.
+abstract class Led<T> {
+  /// Turns on this [Led].
+  T turnOn();
+
+  /// Turns off this [Led].
+  T turnOff();
+
+  /// Toggles this [Led].
+  T toggle();
+}

lib/led.dart → lib/led/powerable_led.dart

@@ -1,30 +1,35 @@
+import 'package:christmas_lights_kata/led/led.dart';
 import 'package:christmas_lights_kata/utils/random_string_extension.dart';
 
 const _poweredLights = '🔴🟡🟢🔵';
 const _offLight = '⚫️';
 
-/// An LED.
-class Led {
-  /// Constructs a new [Led].
-  Led({bool isPowered = false})
+/// A powerable LED.
+class PowerableLed extends Led<bool> {
+  /// Constructs a new [PowerableLed].
+  PowerableLed({bool isPowered = false})
       : _isPowered = isPowered,
         displayLight = _poweredLights.randomChar;
 
   bool _isPowered;
 
-  /// Whether this [Led] is turned on or off.
+  /// Whether this [PowerableLed] is turned on or off.
   bool get isPowered => _isPowered;
 
   /// String for displaying the powered light.
   late final String displayLight;
 
-  /// Turns on this [Led].
+  /// Turns on this [PowerableLed].
+  @override
   bool turnOn() => _isPowered = true;
 
-  /// Turns off this [Led].
+  /// Turns off this [PowerableLed].
+  @override
   bool turnOff() => _isPowered = false;
 
-  /// Toggles the powered state of this [Led] and returns the new state.
+  /// Toggles the powered state of this [PowerableLed] and returns the new
+  /// state.
+  @override
   bool toggle() => _isPowered = !_isPowered;
 
   @override

lib/utils/map_int_v_extension.dart

@@ -0,0 +1,15 @@
+/// Map int to V extension.
+extension MapIntVExtension<V> on Map<int, V> {
+  /// Returns the corresponding value [V], if any, when the [threshold] is
+  /// lower than or equal to one of this [Map] keys.
+  V? valueFromThreshold(int threshold) {
+    final value = this[threshold];
+    if (value != null) return value;
+
+    for (final entry in entries) {
+      if (threshold <= entry.key) return entry.value;
+    }
+
+    return null;
+  }
+}

test/grid_test.dart → test/powerable_grid_test.dart

@@ -1,14 +1,14 @@
 import 'dart:math';
 
-import 'package:christmas_lights_kata/grid.dart';
+import 'package:christmas_lights_kata/grid/powerable_grid.dart';
 import 'package:test/test.dart';
 
 void main() {
-  group('Grid', () {
+  group('PowerableGrid', () {
     group('(new)', () {
       test('creates a squared grid of 10x10', () {
         const gridSize = 10;
-        final grid = Grid(gridSize);
+        final grid = PowerableGrid(gridSize);
         expect(grid.size, gridSize);
         expect(grid.leds.length, gridSize);
         expect(grid.leds.first.length, gridSize);
@@ -18,38 +18,40 @@ void main() {
 
     group('.turnOn()', () {
       test('turns on all LEDs', () {
-        final grid = Grid(10)..turnOn(const Point(0, 0), const Point(9, 9));
+        final grid = PowerableGrid(10)
+          ..turnOn(const Point(0, 0), const Point(9, 9));
         expect(grid.areAllPowered, isTrue);
         print(grid);
       });
 
       test('turns on only selected LEDs', () {
         const start = Point(1, 2);
         const end = Point(5, 6);
-        final grid = Grid(10)..turnOn(start, end);
+        final grid = PowerableGrid(10)..turnOn(start, end);
         expect(grid.isPoweredFrom(start, end), isTrue);
         print(grid);
       });
 
       test('turns on only selected LEDs', () {
         const start = Point(7, 2);
         const end = Point(8, 3);
-        final grid = Grid(10)..turnOn(start, end);
+        final grid = PowerableGrid(10)..turnOn(start, end);
         expect(grid.isPoweredFrom(start, end), isTrue);
         print(grid);
       });
 
       test('turns on only selected LEDs', () {
         const point = Point(1, 1);
-        final grid = Grid(3)..turnOn(point, point);
+        final grid = PowerableGrid(3)..turnOn(point, point);
         expect(grid.isPoweredFrom(point), isTrue);
         print(grid);
       });
     });
 
     group('.turnOff()', () {
       test('turns off all LEDs', () {
-        final grid = Grid(10)..turnOn(const Point(0, 0), const Point(9, 9));
+        final grid = PowerableGrid(10)
+          ..turnOn(const Point(0, 0), const Point(9, 9));
         print(grid);
         grid.turnOff(const Point(0, 0), const Point(9, 9));
         expect(grid.areNonePowered, isTrue);
@@ -59,7 +61,8 @@ void main() {
 
     group('.toggle()', () {
       test('toggles all LEDs', () {
-        final grid = Grid(10)..toggle(const Point(0, 0), const Point(9, 9));
+        final grid = PowerableGrid(10)
+          ..toggle(const Point(0, 0), const Point(9, 9));
         expect(grid.areAllPowered, isTrue);
         print(grid);
         grid.toggle(const Point(0, 0), const Point(9, 9));
@@ -70,7 +73,7 @@ void main() {
 
     group('.poweredLedsCount', () {
       test('returns the number of powered LEDs in the grid', () {
-        final grid = Grid(1000)
+        final grid = PowerableGrid(1000)
           ..turnOn(const Point(887, 9), const Point(959, 629))
           ..turnOn(const Point(454, 398), const Point(844, 448))
           ..turnOff(const Point(539, 243), const Point(559, 965))
@@ -87,12 +90,12 @@ void main() {
   });
 }
 
-extension GridPoweredExtension on Grid {
-  /// Whether all LEDs in this [Grid] are powered.
+extension GridPoweredExtension on PowerableGrid {
+  /// Whether all LEDs in this [PowerableGrid] are powered.
   bool get areAllPowered =>
       leds.every((row) => row.every((led) => led.isPowered));
 
-  /// Whether all LEDs in this [Grid] are not powered.
+  /// Whether all LEDs in this [PowerableGrid] are not powered.
   bool get areNonePowered =>
       leds.every((row) => row.every((led) => !led.isPowered));
 

test/led_test.dart → test/powerable_led_test.dart

@@ -1,41 +1,41 @@
-import 'package:christmas_lights_kata/led.dart';
+import 'package:christmas_lights_kata/led/powerable_led.dart';
 import 'package:test/test.dart';
 
 void main() {
-  group('Led', () {
+  group('PowerableLed', () {
     group('(new)', () {
       test('is not powered by default', () {
-        final led = Led();
+        final led = PowerableLed();
         expect(led.isPowered, isFalse);
         print(led);
       });
 
       test('uses the powered value on construction', () {
-        final led = Led(isPowered: true);
+        final led = PowerableLed(isPowered: true);
         expect(led.isPowered, isTrue);
         print(led);
       });
     });
 
     group('.turnOn()', () {
       test('turns on this LED', () {
-        final led = Led()..turnOn();
+        final led = PowerableLed()..turnOn();
         expect(led.isPowered, isTrue);
         print(led);
       });
     });
 
     group('.turnOff()', () {
       test('turns off this LED', () {
-        final led = Led(isPowered: true)..turnOff();
+        final led = PowerableLed(isPowered: true)..turnOff();
         expect(led.isPowered, isFalse);
         print(led);
       });
     });
 
     group('.toggle()', () {
       test('toggles the powered state of this LED', () {
-        final led = Led()..toggle();
+        final led = PowerableLed()..toggle();
         expect(led.isPowered, isTrue);
         print(led);
         led.toggle();