rebuild PlayerManager to CacheCreationService and optimize creation of the local file cache

MareSynchronos/Utils/FileReplacementComparer.cs

@@ -0,0 +1,45 @@
+using MareSynchronos.Models;
+
+namespace MareSynchronos.Utils;
+
+public class FileReplacementComparer : IEqualityComparer<FileReplacement>
+{
+    public static FileReplacementComparer Instance => _instance;
+    private static FileReplacementComparer _instance = new();
+    private FileReplacementComparer() { }
+    public bool Equals(FileReplacement? x, FileReplacement? y)
+    {
+        if (x == null || y == null) return false;
+        return x.ResolvedPath.Equals(y.ResolvedPath) && CompareLists(x.GamePaths, y.GamePaths);
+    }
+
+    public int GetHashCode(FileReplacement obj)
+    {
+        return HashCode.Combine(obj.ResolvedPath.GetHashCode(StringComparison.OrdinalIgnoreCase), GetOrderIndependentHashCode(obj.GamePaths));
+    }
+
+    private static int GetOrderIndependentHashCode<T>(IEnumerable<T> source)
+    {
+        int hash = 0;
+        foreach (T element in source)
+        {
+            hash = unchecked(hash +
+                EqualityComparer<T>.Default.GetHashCode(element));
+        }
+        return hash;
+    }
+
+    private bool CompareLists(List<string> list1, List<string> list2)
+    {
+        if (list1.Count != list2.Count)
+            return false;
+
+        for (int i = 0; i < list1.Count; i++)
+        {
+            if (!string.Equals(list1[i], list2[i], StringComparison.OrdinalIgnoreCase))
+                return false;
+        }
+
+        return true;
+    }
+}