Refactor stats

Zennysoft.Game.Ma/src/Components/ExperiencePointsComponent.cs

@@ -0,0 +1,56 @@
+using Chickensoft.Collections;
+using System;
+using Zennysoft.Ma.Adapter;
+
+namespace Zennysoft.Game.Ma;
+
+public class ExperiencePointsComponent : IExperiencePointsComponent
+{
+  public IAutoProp<int> CurrentExp => _currentExp;
+
+  public IAutoProp<int> ExpToNextLevel => _expToNextLevel;
+
+  public IAutoProp<double> ExpGainRate => _expGainRate;
+
+  public IAutoProp<int> Level => _level;
+
+  private readonly AutoProp<int> _currentExp;
+
+  private readonly AutoProp<int> _expToNextLevel;
+
+  private readonly AutoProp<double> _expGainRate;
+
+  private readonly AutoProp<int> _level;
+
+  public ExperiencePointsComponent()
+  {
+    var firstLevelExpRequirement = ExpToNextLevelCalculation(1);
+    _expToNextLevel = new AutoProp<int>(firstLevelExpRequirement);
+    _currentExp = new AutoProp<int>(0);
+    _expGainRate = new AutoProp<double>(1.0);
+    _level = new AutoProp<int>(1);
+  }
+
+  public void Gain(int baseExpGain)
+  {
+    var modifiedExpGain = baseExpGain * _expGainRate.Value;
+    var newCurrentExpTotal = modifiedExpGain + _currentExp.Value;
+    while (modifiedExpGain + _currentExp.Value >= _expToNextLevel.Value)
+      LevelUp();
+    var cappedAmount = Math.Min(baseExpGain + _currentExp.Value, _expToNextLevel.Value);
+    _currentExp.OnNext(cappedAmount);
+  }
+
+  public void LevelUp()
+  {
+    _level.OnNext(_level.Value + 1);
+    var expToNextLevel = ExpToNextLevelCalculation(_level.Value);
+    _currentExp.OnNext(_currentExp.Value - _expToNextLevel.Value);
+    _expToNextLevel.OnNext(expToNextLevel);
+  }
+
+  private int ExpToNextLevelCalculation(int nextLevel)
+  {
+    return (int)(6.5 * nextLevel + 4.5 * Math.Pow(nextLevel, 2) + Math.Pow(nextLevel, 3));
+  }
+}