From 243e3507d6de3953211f59f2ebf96d2e9efd1fcf Mon Sep 17 00:00:00 2001
From: Matt Nadareski <mnadareski@outlook.com>
Date: Tue, 21 Dec 2021 14:20:27 -0800
Subject: [PATCH] Fix and better document DatItem.Sort

There was an issue around how items from different sources were handled, in that sources were checked first and not last. This was due to a few assumptions about source IDs and DAT order in general. This may end up causing different output hashes for merged DATs.
---
 SabreTools.DatItems/DatItem.cs | 39 +++++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/SabreTools.DatItems/DatItem.cs b/SabreTools.DatItems/DatItem.cs
index 2e42a7a5..50512d64 100644
--- a/SabreTools.DatItems/DatItem.cs
+++ b/SabreTools.DatItems/DatItem.cs
@@ -749,25 +749,40 @@ namespace SabreTools.DatItems
                 try
                 {
                     NaturalComparer nc = new NaturalComparer();
-                    if (x.Source.Index == y.Source.Index)
-                    {
-                        if (x.Machine.Name == y.Machine.Name)
-                        {
-                            if (x.ItemType == y.ItemType)
-                            {
-                                if (Path.GetDirectoryName(Utilities.RemovePathUnsafeCharacters(x.GetName() ?? string.Empty)) == Path.GetDirectoryName(Utilities.RemovePathUnsafeCharacters(y.GetName() ?? string.Empty)))
-                                    return nc.Compare(Path.GetFileName(Utilities.RemovePathUnsafeCharacters(x.GetName() ?? string.Empty)), Path.GetFileName(Utilities.RemovePathUnsafeCharacters(y.GetName() ?? string.Empty)));
 
-                                return nc.Compare(Path.GetDirectoryName(Utilities.RemovePathUnsafeCharacters(x.GetName() ?? string.Empty)), Path.GetDirectoryName(Utilities.RemovePathUnsafeCharacters(y.GetName() ?? string.Empty)));
+                    // If machine names match, more refinement is needed
+                    if (x.Machine.Name == y.Machine.Name)
+                    {
+                        // If item types match, more refinement is needed
+                        if (x.ItemType == y.ItemType)
+                        {
+                            string xDirectoryName = Path.GetDirectoryName(Utilities.RemovePathUnsafeCharacters(x.GetName() ?? string.Empty));
+                            string yDirectoryName = Path.GetDirectoryName(Utilities.RemovePathUnsafeCharacters(y.GetName() ?? string.Empty));
+
+                            // If item directory names match, more refinement is needed
+                            if (xDirectoryName == yDirectoryName)
+                            {
+                                string xName = Path.GetFileName(Utilities.RemovePathUnsafeCharacters(x.GetName() ?? string.Empty));
+                                string yName = Path.GetFileName(Utilities.RemovePathUnsafeCharacters(y.GetName() ?? string.Empty));
+
+                                // If item names match, then compare on machine or source, depending on the flag
+                                if (xName == yName)
+                                    return (norename ? nc.Compare(x.Machine.Name, y.Machine.Name) : x.Source.Index - y.Source.Index);
+
+                                // Otherwise, just sort based on item names
+                                return nc.Compare(xName, yName);
                             }
 
-                            return x.ItemType - y.ItemType;
+                            // Otherwise, just sort based on directory name
+                            return nc.Compare(xDirectoryName, yDirectoryName);
                         }
 
-                        return nc.Compare(x.Machine.Name, y.Machine.Name);
+                        // Otherwise, just sort based on item type
+                        return x.ItemType - y.ItemType;
                     }
 
-                    return (norename ? nc.Compare(x.Machine.Name, y.Machine.Name) : x.Source.Index - y.Source.Index);
+                    // Otherwise, just sort based on machine name
+                    return nc.Compare(x.Machine.Name, y.Machine.Name);
                 }
                 catch
                 {