add PreconditionRequirement and RelatedModule requirement

Assets/Engine/Runtime/Requirements/PreconditionRequirement.cs

@@ -0,0 +1,44 @@
+using System.Collections.Generic;
+using EscapeRoomEngine.Engine.Runtime.Modules;
+using UnityEngine;
+using Logger = EscapeRoomEngine.Engine.Runtime.Utilities.Logger;
+using LogType = EscapeRoomEngine.Engine.Runtime.Utilities.LogType;
+
+namespace EscapeRoomEngine.Engine.Runtime.Requirements
+{
+    public abstract class PreconditionRequirement : Requirement<bool>
+    {
+        protected static readonly HashSet<bool> TrueSet = new(new[] { true }), FalseSet = new(new[] { false });
+
+        protected abstract override IEnumerable<bool> GenerateCandidates(Module module, Space space);
+
+        public static bool CheckPreconditions(Module module, Space space)
+        {
+            Debug.Log($"{module}, {module.description.preconditionRequirements}");
+            if (module.description.preconditionRequirements.Count == 0)
+            {
+                // don't evaluate requirements if there are none
+                return true;
+            }
+            
+            var preconditionsMet = Candidates(
+                    TrueSet,
+                    module.description.preconditionRequirements,
+                    module, space)
+                .Contains(true);
+
+            Logger.Log(
+                preconditionsMet
+                    ? $"Preconditions for {module} satisfied"
+                    : $"Could not satisfy preconditions for {module}",
+                LogType.ModulePlacement);
+
+            return preconditionsMet;
+        }
+
+        protected static HashSet<bool> SetFor(bool value)
+        {
+            return value ? TrueSet : FalseSet;
+        }
+    }
+}