Add bounds hazards and triggers

tests/SideScrollerGame.Sim.Tests/SimulationStepTests.cs

@@ -27,11 +27,71 @@ public sealed class SimulationStepTests
         Assert.Equal(30, player.AimAxisX);
         Assert.Equal(40, player.AimAxisY);
         Assert.Equal(3, player.SelectedWeaponSlot);
+        Assert.Equal(10, player.Health);
         Assert.NotEqual(0, player.ButtonMask);
         Assert.Equal(result.StateHash, simulation.CurrentSnapshot.StateHash);
         Assert.NotEqual(0UL, simulation.CurrentSnapshot.LastRandomValue);
     }
 
+    [Fact]
+    public void Step_ClampsPlayerToWorldBounds()
+    {
+        Simulation simulation = new(SimulationTestFactory.CreateGameDefinition(new(new(0, 0), new(11, 20))), SimulationTestFactory.CreateConfig(), 7);
+
+        var result = simulation.Step(SimulationTestFactory.CreateTick(1, new MoveAxisChanged(new(1), 5, 0)));
+
+        var player = simulation.CurrentState.GetRequiredPlayer(new(1));
+        Assert.Equal(11, player.Position.m_X.ToIntRound());
+        Assert.Contains(result.Events, static e => e.Kind == "PlayerClamped");
+    }
+
+    [Fact]
+    public void Step_AppliesHazardDamage()
+    {
+        Simulation simulation = new(SimulationTestFactory.CreateGameDefinition(hazards: ImmutableArray.Create(new HazardDefinition("lava", new(new(11, 20), new(12, 21)), 3))), SimulationTestFactory.CreateConfig(), 7);
+
+        var result = simulation.Step(SimulationTestFactory.CreateTick(1, new MoveAxisChanged(new(1), 1, 0)));
+
+        var player = simulation.CurrentState.GetRequiredPlayer(new(1));
+        Assert.Equal(7, player.Health);
+        Assert.Contains(result.Events, static e => e.Kind == "PlayerDamaged");
+    }
+
+    [Fact]
+    public void Step_IgnoresHazardsWhenPlayerIsOutside()
+    {
+        Simulation simulation = new(SimulationTestFactory.CreateGameDefinition(hazards: ImmutableArray.Create(new HazardDefinition("lava", new(new(50, 50), new(60, 60)), 3))), SimulationTestFactory.CreateConfig(), 7);
+
+        var result = simulation.Step(SimulationTestFactory.CreateTick(1, new MoveAxisChanged(new(1), 1, 0)));
+
+        Assert.Equal(10, simulation.CurrentState.GetRequiredPlayer(new(1)).Health);
+        Assert.DoesNotContain(result.Events, static e => e.Kind == "PlayerDamaged");
+    }
+
+    [Fact]
+    public void Step_ActivatesTriggerOnlyOnce()
+    {
+        Simulation simulation = new(SimulationTestFactory.CreateGameDefinition(triggers: ImmutableArray.Create(new TriggerDefinition("checkpoint_a", new(new(11, 20), new(12, 21)), "TriggerActivated"))), SimulationTestFactory.CreateConfig(), 7);
+
+        var first = simulation.Step(SimulationTestFactory.CreateTick(1, new MoveAxisChanged(new(1), 1, 0)));
+        var second = simulation.Step(SimulationTestFactory.CreateTick(2, new MoveAxisChanged(new(1), 0, 0)));
+
+        Assert.Contains(first.Events, static e => e.Kind == "TriggerActivated");
+        Assert.DoesNotContain(second.Events, static e => e.Kind == "TriggerActivated");
+        Assert.Contains("checkpoint_a", simulation.CurrentState.ActivatedTriggerIds);
+    }
+
+    [Fact]
+    public void Step_IgnoresTriggersWhenPlayerIsOutside()
+    {
+        Simulation simulation = new(SimulationTestFactory.CreateGameDefinition(triggers: ImmutableArray.Create(new TriggerDefinition("checkpoint_a", new(new(50, 50), new(60, 60)), "TriggerActivated"))), SimulationTestFactory.CreateConfig(), 7);
+
+        var result = simulation.Step(SimulationTestFactory.CreateTick(1, new MoveAxisChanged(new(1), 1, 0)));
+
+        Assert.DoesNotContain(result.Events, static e => e.Kind == "TriggerActivated");
+        Assert.Empty(simulation.CurrentState.ActivatedTriggerIds);
+    }
+
     [Fact]
     public void Step_RejectsUnexpectedTickNumbers()
     {
@@ -65,13 +125,33 @@ public sealed class SimulationStepTests
     [Fact]
     public void Constructor_RejectsDuplicatePlayers()
     {
-        GameDefinition definition = new(ImmutableArray.Create(new(new(1), new(0, 0)), new PlayerDefinition(new(1), new(2, 3))));
+        GameDefinition definition = new(new(new(new(0, 0), new(100, 100)), ImmutableArray<HazardDefinition>.Empty, ImmutableArray<TriggerDefinition>.Empty), ImmutableArray.Create(new(new(1), new(0, 0), 10), new PlayerDefinition(new(1), new(2, 3), 10)));
 
         var exception = Assert.Throws<InvalidOperationException>(() => new Simulation(definition, SimulationTestFactory.CreateConfig(), 11));
 
         Assert.Contains("Duplicate player id 1", exception.Message);
     }
 
+    [Fact]
+    public void Constructor_RejectsSpawnOutsideBounds()
+    {
+        GameDefinition definition = new(new(new(new(0, 0), new(5, 5)), ImmutableArray<HazardDefinition>.Empty, ImmutableArray<TriggerDefinition>.Empty), ImmutableArray.Create(new PlayerDefinition(new(1), new(10, 20), 10)));
+
+        var exception = Assert.Throws<InvalidOperationException>(() => new Simulation(definition, SimulationTestFactory.CreateConfig(), 11));
+
+        Assert.Contains("spawn must start inside world bounds", exception.Message);
+    }
+
+    [Fact]
+    public void Constructor_RejectsNonPositiveHealth()
+    {
+        GameDefinition definition = new(new(new(new(0, 0), new(100, 100)), ImmutableArray<HazardDefinition>.Empty, ImmutableArray<TriggerDefinition>.Empty), ImmutableArray.Create(new PlayerDefinition(new(1), new(1, 1), 0)));
+
+        var exception = Assert.Throws<InvalidOperationException>(() => new Simulation(definition, SimulationTestFactory.CreateConfig(), 11));
+
+        Assert.Contains("positive health", exception.Message);
+    }
+
     [Fact]
     public void Constructor_RejectsNullDefinition()
     {