Remove unused NodeData instantiations

Solver/Crafty/ActionSet.cs

@@ -56,4 +56,9 @@ public struct ActionSet
     public readonly ActionType ElementAt(int index) => ToAction(NthBitSet(bits, index) - 1);
 
     public readonly int Count => BitOperations.PopCount(bits);
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public readonly ActionType SelectRandom(Random random) => ElementAt(random.Next(Count));
+
+    public readonly ActionType First() => ElementAt(0);
 }

Solver/Crafty/SimulationNode.cs

@@ -10,10 +10,7 @@ public readonly struct SimulationNode
     public readonly CompletionState SimulationCompletionState;
     public readonly NodeData Data;
 
-    public CompletionState CompletionState =>
-        Data.AvailableActions.Count == 0 && SimulationCompletionState == CompletionState.Incomplete ?
-        CompletionState.NoMoreActions :
-        SimulationCompletionState;
+    public CompletionState CompletionState => GetCompletionState(SimulationCompletionState, Data.AvailableActions);
 
     public bool IsComplete => CompletionState != CompletionState.Incomplete;
 
@@ -25,9 +22,16 @@ public readonly struct SimulationNode
         Data = data;
     }
 
-    public float? CalculateScore()
+    public static CompletionState GetCompletionState(CompletionState simCompletionState, ActionSet actions) =>
+        actions.Count == 0 && simCompletionState == CompletionState.Incomplete ?
+        CompletionState.NoMoreActions :
+        simCompletionState;
+
+    public float? CalculateScore() => CalculateScoreForState(State, SimulationCompletionState);
+
+    public static float? CalculateScoreForState(SimulationState state, CompletionState completionState)
     {
-        if (CompletionState != CompletionState.ProgressComplete)
+        if (completionState != CompletionState.ProgressComplete)
             return null;
 
         static float Apply(float bonus, float value, float target) =>
@@ -41,30 +45,30 @@ public readonly struct SimulationNode
 
         var progressScore = Apply(
             progressBonus,
-            State.Progress,
-            State.Input.Recipe.MaxProgress
+            state.Progress,
+            state.Input.Recipe.MaxProgress
         );
 
         var qualityScore = Apply(
             qualityBonus,
-            State.Quality,
-            State.Input.Recipe.MaxQuality
+            state.Quality,
+            state.Input.Recipe.MaxQuality
         );
 
         var durabilityScore = Apply(
             durabilityBonus,
-            State.Durability,
-            State.Input.Recipe.MaxDurability
+            state.Durability,
+            state.Input.Recipe.MaxDurability
         );
 
         var cpScore = Apply(
             cpBonus,
-            State.CP,
-            State.Input.Stats.CP
+            state.CP,
+            state.Input.Stats.CP
         );
 
         var fewerStepsScore =
-            fewerStepsBonus * (1f - ((float)(State.ActionCount + 1) / Solver.MaxStepCount));
+            fewerStepsBonus * (1f - ((float)(state.ActionCount + 1) / Solver.MaxStepCount));
 
         return progressScore + qualityScore + durabilityScore + cpScore + fewerStepsScore;
     }

Solver/Crafty/Solver.cs

@@ -36,14 +36,20 @@ public class Solver
     {
     }
 
-    private SimulationNode Execute(SimulationState state, ActionType action, bool strict)
+    private (SimulationState NewState, CompletionState SimulatorCompletionState, ActionSet AvailableActions) ExecuteSimple(SimulationState state, ActionType action, bool strict)
     {
         (_, var newState) = Simulator.Execute(state, action);
+        return (newState, Simulator.CompletionState, Simulator.AvailableActionsHeuristic(strict));
+    }
+
+    private SimulationNode Execute(SimulationState state, ActionType action, bool strict)
+    {
+        (var newState, var completionState, var newActions) = ExecuteSimple(state, action, strict);
         return new(
             newState,
             action,
-            Simulator.CompletionState,
-            new() { AvailableActions = Simulator.AvailableActionsHeuristic(strict) }
+            completionState,
+            new() { AvailableActions = newActions }
         );
     }
 
@@ -158,37 +164,38 @@ public class Solver
         if (initialState.IsComplete)
             return (initialNode, initialState.CompletionState, initialState.CalculateScore() ?? 0);
 
-        var randomIdx = 0;// Random.Next(initialState.Data.AvailableActions.Count);
-        var randomAction = initialState.Data.AvailableActions.ElementAt(randomIdx);
+        var randomAction = initialState.Data.AvailableActions.First();
         initialState.Data.AvailableActions.RemoveAction(randomAction);
-        var expandedState = Execute(initialState.State, randomAction, true);
-        var expandedNode = initialNode.Add(expandedState);
+        var expandedNode = initialNode.Add(Execute(initialState.State, randomAction, true));
 
         // playout to a terminal state
-        var currentState = expandedNode.State;
+        var currentState = expandedNode.State.State;
+        var currentCompletionState = expandedNode.State.SimulationCompletionState;
+        var currentActions = expandedNode.State.Data.AvailableActions;
+
         byte actionCount = 0;
         Span<ActionType> actions = stackalloc ActionType[MaxStepCount];
         while (true)
         {
-            if (currentState.IsComplete)
+            if (SimulationNode.GetCompletionState(currentCompletionState, currentActions) != CompletionState.Incomplete)
                 break;
-            randomIdx = 0;// Random.Next(currentState.Data.AvailableActions.Count);
-            randomAction = currentState.Data.AvailableActions.ElementAt(randomIdx);
+            randomAction = currentActions.First();
             actions[actionCount++] = randomAction;
-            currentState = Execute(currentState.State, randomAction, true);
+            (currentState, currentCompletionState, currentActions) = ExecuteSimple(currentState, randomAction, true);
         }
 
         // store the result if a max score was reached
-        var score = currentState.CalculateScore() ?? 0;
-        if (currentState.CompletionState == CompletionState.ProgressComplete)
+        currentCompletionState = SimulationNode.GetCompletionState(currentCompletionState, currentActions);
+        var score = SimulationNode.CalculateScoreForState(currentState, currentCompletionState) ?? 0;
+        if (currentCompletionState == CompletionState.ProgressComplete)
         {
             if (score >= ScoreStorageThreshold && score >= RootNode.State.Data.Scores.MaxScore)
             {
                 (var terminalNode, _) = ExecuteActions(expandedNode, actions[..actionCount], true);
-                return (terminalNode, currentState.CompletionState, score);
+                return (terminalNode, currentCompletionState, score);
             }
         }
-        return (expandedNode, currentState.CompletionState, score);
+        return (expandedNode, currentCompletionState, score);
     }
 
     public static void Backpropagate(Node startNode, Node targetNode, float score)