Add objectives, stage config, and GameEngine session core

Sealed Objective types (clearGems/reachScore/clearLines) with JSON round-trip; StageConfig with preset cells and star thresholds; GameEngine orchestrating placement -> clear -> scoring -> objectives with stuck detection, one-shot rescue (continue / +5 moves), and deterministic per-attempt RNG. 100-game headless stress test and pure-Dart architecture guard. 76 tests green. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-11 13:11:31 +09:00
parent 0210c14858
commit 62cbb4b16a
10 changed files with 886 additions and 1 deletions
@@ -0,0 +1,63 @@
+import 'package:block_seasons/core/rng.dart';
+import 'package:block_seasons/game/engine/game_engine.dart';
+import 'package:block_seasons/game/models/grid.dart';
+import 'package:block_seasons/game/models/stage.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+StageConfig _endlessStage(int seed) => StageConfig.fromJson({
+      'id': 'stress_$seed',
+      'seed': seed,
+      'moveLimit': 40,
+      'preset': const <Map<String, dynamic>>[],
+      'objectives': [
+        {'type': 'reachScore', 'target': 99999999},
+      ],
+      'stars': {
+        'two': {'movesLeft': 5},
+        'three': {'movesLeft': 10},
+      },
+      'generatorProfile': 'mid',
+    });
+
+void main() {
+  test('100 seeded random games run to a terminal state without violations',
+      () {
+    for (var seed = 0; seed < 100; seed++) {
+      final engine = GameEngine(_endlessStage(seed));
+      final rng = SeededRng(seed * 7919 + 1);
+      var guard = 0;
+
+      while (engine.phase == GamePhase.playing) {
+        guard++;
+        expect(guard, lessThan(300), reason: 'seed $seed: game never ended');
+
+        // Enumerate all legal moves; the engine promises at least one exists
+        // while phase == playing.
+        final moves = <(int, int, int)>[];
+        for (var i = 0; i < engine.tray.length; i++) {
+          for (var y = 0; y < GridState.size; y++) {
+            for (var x = 0; x < GridState.size; x++) {
+              if (engine.tryPlaceWouldSucceed(i, x, y)) moves.add((i, x, y));
+            }
+          }
+        }
+        expect(moves, isNotEmpty,
+            reason: 'seed $seed: playing phase but no legal move');
+
+        final (i, x, y) = moves[rng.nextInt(moves.length)];
+        final result = engine.tryPlace(i, x, y);
+        expect(result, isNotNull, reason: 'seed $seed: legal move rejected');
+
+        // Invariants after every move.
+        expect(engine.tray.length, inInclusiveRange(1, 3),
+            reason: 'seed $seed');
+        expect(engine.movesUsed, lessThanOrEqualTo(40), reason: 'seed $seed');
+        expect(engine.score, greaterThanOrEqualTo(0), reason: 'seed $seed');
+      }
+
+      // The score objective is unreachable, so every game ends stuck.
+      expect(engine.phase, GamePhase.stuck, reason: 'seed $seed');
+      expect(engine.stuckReason, isNotNull, reason: 'seed $seed');
+    }
+  });
+}