Backfill SkillApplier tests

Skills that target Character automatically heal
Negative damage multiplier isn't it any more.

source/TextBlade.Core.Tests/Battle/BattleResultsApplierTests.cs

@@ -2,7 +2,6 @@
 using NUnit.Framework;
 using TextBlade.Core.Battle;
 using TextBlade.Core.Commands;
-using TextBlade.Core.Commands.Display;
 using TextBlade.Core.IO;
 using TextBlade.Core.Locations;
 

source/TextBlade.Core.Tests/Battle/SkillApplierTests.cs

@@ -0,0 +1,102 @@
+using NSubstitute;
+using NUnit.Framework;
+using TextBlade.Core.Battle;
+using TextBlade.Core.Characters;
+using TextBlade.Core.IO;
+
+namespace TextBlade.Core.Tests.Battle;
+
+[TestFixture]
+public class SkillApplierTests
+{
+    [Test]
+    public void Apply_AppliesDamage_IfTargetIsMonster()
+    {
+        // Arrange
+        var applier = new SkillApplier(Substitute.For<IConsole>());
+        // Skills use Strength right now (total strength), not Special
+        var user = new Character("Skill User", 1, 20, 1, 1);
+        var skill = new Skill() { DamageMultiplier = 1.5f };
+        var target = new Monster("Slime", 100, 1, 5);
+        int expectedDamage = (int)((user.TotalStrength - target.Toughness) * skill.DamageMultiplier);
+
+        // Act
+        applier.Apply(user, skill, [target]);
+
+        // Assert
+        var actualDamage = target.TotalHealth - target.CurrentHealth;
+        Assert.That(actualDamage, Is.EqualTo(expectedDamage));
+    }
+
+    [Test]
+    public void Apply_Heals_IfTargetIsCharacter()
+    {
+        // Arrange
+        var applier = new SkillApplier(Substitute.For<IConsole>());
+        // Healing uses Special
+        var user = new Character("Skill User", 1, 1, 1, 20);
+        var skill = new Skill() { DamageMultiplier = 1.5f };
+        var target = new Character("Ex-Slime", 100, 1, 5) { CurrentHealth = 0 };
+        int expectedHealing = (int)(user.Special * skill.DamageMultiplier * 2);
+
+        // Act
+        applier.Apply(user, skill, [target]);
+
+        // Assert
+        var actualHealing = target.CurrentHealth;
+        Assert.That(actualHealing, Is.EqualTo(expectedHealing));
+    }
+
+    [Test]
+    public void Apply_DoublesDamage_IfTargetWeaknessMatchesSkillDamageType()
+    {
+        // Arrange
+        var applier = new SkillApplier(Substitute.For<IConsole>());
+        var user = new Character("Skill User", 1, 20, 1, 1);
+        var skill = new Skill() { DamageMultiplier = 1f, DamageType = "Time" };
+        var target = new Monster("Slime", 100, 1, 5, weakness: "Time");
+        int expectedDamage = (user.TotalStrength - target.Toughness) * 2; // x2 = weakness
+
+        // Act
+        applier.Apply(user, skill, [target]);
+
+        // Assert
+        var actualDamage = target.TotalHealth - target.CurrentHealth;
+        Assert.That(actualDamage, Is.EqualTo(expectedDamage));
+    }
+
+    [Test]
+    public void Apply_InflictsStatus()
+    {
+        // Arrange
+        var applier = new SkillApplier(Substitute.For<IConsole>());
+        // Skills use Strength right now (total strength), not Special
+        var user = new Character("Skill User", 1, 1, 1, 1);
+        var skill = new Skill() { StatusInflicted = "Anxiety", StatusStacks = 4 };
+        var target = new Monster("Slime", 1, 1, 1);
+
+        // Act
+        applier.Apply(user, skill, [target]);
+
+        // Assert
+        Assert.That(target.StatusStacks, Does.ContainKey(skill.StatusInflicted));
+        Assert.That(target.StatusStacks[skill.StatusInflicted], Is.EqualTo(skill.StatusStacks));
+    }
+
+    [Test]
+    public void Apply_DeductsSkillPointsCost()
+    {
+        // Arrange
+        var applier = new SkillApplier(Substitute.For<IConsole>());
+        // Skills use Strength right now (total strength), not Special
+        var user = new Character("Skill User", 1, 1, 1, 1) { TotalSkillPoints = 77, CurrentSkillPoints = 66 };
+        var skill = new Skill() { Cost = 7 };
+        var target = new Monster("Slime", 1, 1, 1);
+
+        // Act
+        applier.Apply(user, skill, [target]);
+
+        // Assert
+        Assert.That(user.CurrentSkillPoints, Is.EqualTo(66 - skill.Cost));
+    }
+}

source/TextBlade.Core.Tests/Content/Data/Skills.json

@@ -38,7 +38,7 @@
     },
     "Heal":
     {
-        "DamageMultiplier":-1.5,
+        "DamageMultiplier": 1.5,
         "Cost": 5,
         "Target":"Character"
     }

source/TextBlade.Core/Battle/SkillApplier.cs

@@ -1,4 +1,3 @@
-using System.Text;
 using TextBlade.Core.Characters;
 using TextBlade.Core.IO;
 
@@ -27,7 +26,8 @@ internal void Apply(Character user, Skill skill, IEnumerable<Entity> targets)
 
     private void ApplyDamage(Character user, Skill skill, Entity target)
     {
-        /////// TODO: REFACTOR so this method is not polymorphic
+        /////// TODO: REFACTOR so this method is not polymorphic: healing *and* damage.
+
         ArgumentNullException.ThrowIfNull(target);
         float damage = 0;
         var hitWeakness = false;
@@ -45,7 +45,7 @@ private void ApplyDamage(Character user, Skill skill, Entity target)
         else if (target is Character)
         {
             // If you're healing, heal for 2x
-            damage = (int)Math.Ceiling(user.Special * skill.DamageMultiplier * 2);
+            damage = (int)Math.Ceiling(user.Special * -skill.DamageMultiplier * 2);
         }
 
         var roundedDamage = (int)damage;

source/TextBlade.Core/Characters/PartyManagement/EquipmentEquipper.cs

@@ -24,7 +24,7 @@ internal bool EquipIfRequested(Item itemData, Inventory inventory, List<Characte
 
         _console.WriteLine("Equip for who? Or press 0 or b to cancel.");
 
-        var input = 0;
+        int input;
         var rawInput = _console.ReadKey();
         if (rawInput == '0' || rawInput == 'b' || !int.TryParse(rawInput.ToString(), out input))
         {

source/VoidWalker.Main/Content/Data/Skills.json

@@ -33,7 +33,7 @@
     },
     "Heal":
     {
-        "DamageMultiplier": -1.5,
+        "DamageMultiplier": 1.5,
         "Cost": 5,
         "Target":"Character"
     }