Initial

MareSynchronos/PlayerData/Data/FileReplacementDataComparer.cs

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+using MareSynchronos.API.Data;
+
+namespace MareSynchronos.PlayerData.Data;
+
+public class FileReplacementDataComparer : IEqualityComparer<FileReplacementData>
+{
+    private static readonly FileReplacementDataComparer _instance = new();
+
+    private FileReplacementDataComparer()
+    { }
+
+    public static FileReplacementDataComparer Instance => _instance;
+
+    public bool Equals(FileReplacementData? x, FileReplacementData? y)
+    {
+        if (x == null || y == null) return false;
+        return x.Hash.Equals(y.Hash) && CompareHashSets(x.GamePaths.ToHashSet(StringComparer.Ordinal), y.GamePaths.ToHashSet(StringComparer.Ordinal)) && string.Equals(x.FileSwapPath, y.FileSwapPath, StringComparison.Ordinal);
+    }
+
+    public int GetHashCode(FileReplacementData obj)
+    {
+        return HashCode.Combine(obj.Hash.GetHashCode(StringComparison.OrdinalIgnoreCase), GetOrderIndependentHashCode(obj.GamePaths), StringComparer.Ordinal.GetHashCode(obj.FileSwapPath));
+    }
+
+    private static bool CompareHashSets(HashSet<string> list1, HashSet<string> list2)
+    {
+        if (list1.Count != list2.Count)
+            return false;
+
+        for (int i = 0; i < list1.Count; i++)
+        {
+            if (!string.Equals(list1.ElementAt(i), list2.ElementAt(i), StringComparison.OrdinalIgnoreCase))
+                return false;
+        }
+
+        return true;
+    }
+
+    private static int GetOrderIndependentHashCode<T>(IEnumerable<T> source) where T : notnull
+    {
+        int hash = 0;
+        foreach (T element in source)
+        {
+            hash = unchecked(hash +
+                EqualityComparer<T>.Default.GetHashCode(element));
+        }
+        return hash;
+    }
+}