Big script cleanup. Remove the examples from Ropes' external package

Assets/Scripts/PuzzleS/PuzzleGraphUtility.cs

@@ -0,0 +1,65 @@
+using System.Collections.Generic;
+using UnityEngine;
+
+/// <summary>
+/// Utility functions for building and querying puzzle step dependency graphs.
+/// </summary>
+public static class PuzzleGraphUtility
+{
+    /// <summary>
+    /// Builds a dependency graph: for each step, lists the steps it depends on.
+    /// </summary>
+    /// <param name="steps">All puzzle steps.</param>
+    /// <returns>Dictionary mapping each step to the list of steps it depends on.</returns>
+    public static Dictionary<PuzzleStepSO, List<PuzzleStepSO>> BuildDependencyGraph(IEnumerable<PuzzleStepSO> steps)
+    {
+        var graph = new Dictionary<PuzzleStepSO, List<PuzzleStepSO>>();
+        foreach (var step in steps)
+        {
+            graph[step] = new List<PuzzleStepSO>();
+        }
+        foreach (var step in steps)
+        {
+            foreach (var unlocked in step.unlocks)
+            {
+                if (!graph.ContainsKey(unlocked))
+                    graph[unlocked] = new List<PuzzleStepSO>();
+                graph[unlocked].Add(step);
+            }
+        }
+        return graph;
+    }
+
+    /// <summary>
+    /// Finds initial steps (no dependencies).
+    /// </summary>
+    /// <param name="graph">Dependency graph.</param>
+    /// <returns>List of steps with no dependencies.</returns>
+    public static List<PuzzleStepSO> FindInitialSteps(Dictionary<PuzzleStepSO, List<PuzzleStepSO>> graph)
+    {
+        var initial = new List<PuzzleStepSO>();
+        foreach (var kvp in graph)
+        {
+            if (kvp.Value.Count == 0)
+                initial.Add(kvp.Key);
+        }
+        return initial;
+    }
+
+    /// <summary>
+    /// Finds all steps unlocked by a given step.
+    /// </summary>
+    /// <param name="step">The step to check unlocks for.</param>
+    /// <param name="allSteps">All puzzle steps.</param>
+    /// <returns>List of steps unlocked by the given step.</returns>
+    public static List<PuzzleStepSO> FindUnlocks(PuzzleStepSO step, IEnumerable<PuzzleStepSO> allSteps)
+    {
+        var unlocks = new List<PuzzleStepSO>();
+        foreach (var s in allSteps)
+        {
+            if (s.unlocks.Contains(step))
+                unlocks.Add(s);
+        }
+        return unlocks;
+    }
+}