From 2b9dc19c62e29e6713c1032728936003db449ffa Mon Sep 17 00:00:00 2001
From: Filip Strajnar <filip.strajnar@gmail.com>
Date: Sat, 11 May 2024 13:34:39 +0200
Subject: [PATCH] Unfinished implementation of RecursiveFieldsEqual.

---
 AioNet.Reflection/DeepComparison.cs | 54 +++++++++++++++++++++++++++--
 1 file changed, 52 insertions(+), 2 deletions(-)

diff --git a/AioNet.Reflection/DeepComparison.cs b/AioNet.Reflection/DeepComparison.cs
index 85a8cd1..5be99dd 100644
--- a/AioNet.Reflection/DeepComparison.cs
+++ b/AioNet.Reflection/DeepComparison.cs
@@ -1,4 +1,54 @@
-namespace AioNet.Reflection
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+
+namespace AioNet.Reflection
 {
-    public class DeepComparison { }
+    public static class DeepComparison
+    {
+        public static bool RecursiveFieldsEqual<T>(this T first, T second)
+        {
+            Type type = typeof(T);
+            return first.RecursiveFieldsEqual(second, type);
+        }
+
+        public static bool RecursiveFieldsEqual(this object first, object second, Type type)
+        {
+            // If both are null, return true.
+            if (first is null && second is null)
+            {
+                return true;
+            }
+
+            // If one of them is null and the other one isn't, return false.
+            if (first is null || second is null)
+            {
+                return false;
+            }
+
+            // If type is value type or a String, simply return result of Equals.
+            if (type.IsValueType || type.Equals(typeof(string)))
+            {
+                return first.Equals(second);
+            }
+
+            // If type is IEnumerable, compare individual elements.
+            if (type.GetInterface("System.Collections.IEnumerable") != null)
+            {
+                throw new NotImplementedException();
+            }
+
+            IEnumerable<FieldInfo> fields = type.GetRuntimeFields();
+
+            return fields.All(field =>
+            {
+                return RecursiveFieldsEqual(
+                    field.GetValue(first),
+                    field.GetValue(second),
+                    field.FieldType
+                );
+            });
+        }
+    }
 }