From af313cf6b4a063f3f3871b564d534a9e8d4888c8 Mon Sep 17 00:00:00 2001
From: ArchLeaders <archleadership28@gmail.com>
Date: Fri, 15 Mar 2024 10:29:12 -0700
Subject: [PATCH] Optimize Sarc.Write

---
 src/SarcLibrary/Sarc.cs               | 32 ++++++++++++++-------------
 src/SarcLibrary/SarcLibrary.csproj    |  3 ++-
 src/SarcLibrary/Writers/SfatWriter.cs |  4 ++--
 src/SarcLibrary/Writers/SfntWriter.cs |  2 +-
 4 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/src/SarcLibrary/Sarc.cs b/src/SarcLibrary/Sarc.cs
index b85c993..476ae61 100644
--- a/src/SarcLibrary/Sarc.cs
+++ b/src/SarcLibrary/Sarc.cs
@@ -1,5 +1,5 @@
 global using SarcNodeData = (string Name, (uint FileNameHash, System.ArraySegment<byte> Data, int Alignment) Value);
-
+using CommunityToolkit.HighPerformance.Buffers;
 using Revrs;
 using SarcLibrary.Structures;
 using SarcLibrary.Writers;
@@ -69,29 +69,31 @@ public unsafe void Write(Stream stream, Endianness? endianness = null, bool lega
 
         writer.Move(sizeof(SarcHeader));
 
-        SarcNodeData[] sorted = this
-            .Select(x => (x.Key, Value: (
-                Hash: SfatWriter.GetFileNameHash(x.Key), x.Value,
-                Alignment: SarcAlignment.Estimate(x, endianness.Value, legacy)
-            )))
-            .OrderBy(x => x.Value.Hash)
-            .ToArray();
+        int sarcAlignment = 1;
+        using SpanOwner<SarcNodeData> sorted = SpanOwner<SarcNodeData>.Allocate(Count);
+
+        int i = -1;
+        foreach (KeyValuePair<string, ArraySegment<byte>> entry in this) {
+            uint hash = SfatWriter.GetFileNameHash(entry.Key);
 
-        SfatWriter.Write(writer, sorted, IsHashOnly);
+            int alignment = SarcAlignment.Estimate(entry, endianness.Value, legacy);
+            sarcAlignment = SarcAlignment.LCM(sarcAlignment, alignment);
 
-        if (!IsHashOnly) {
-            SfntWriter.Write(writer, sorted);
+            sorted.Span[++i] = (entry.Key, Value: (hash, entry.Value, alignment));
         }
 
-        int sarcAlignment = 1;
-        foreach ((var _, var value) in sorted) {
-            sarcAlignment = SarcAlignment.LCM(sarcAlignment, value.Alignment);
+        sorted.Span.Sort((SarcNodeData x, SarcNodeData y) => x.Value.FileNameHash.CompareTo(y.Value.FileNameHash));
+
+        SfatWriter.Write(ref writer, sorted.Span, IsHashOnly);
+
+        if (!IsHashOnly) {
+            SfntWriter.Write(ref writer, sorted.Span);
         }
 
         writer.Align(sarcAlignment);
 
         int dataOffset = (int)writer.Position;
-        foreach ((var _, var value) in sorted) {
+        foreach ((var _, var value) in sorted.Span) {
             writer.Align(value.Alignment);
             writer.Write(value.Data);
         }
diff --git a/src/SarcLibrary/SarcLibrary.csproj b/src/SarcLibrary/SarcLibrary.csproj
index cfde6d5..708d61c 100644
--- a/src/SarcLibrary/SarcLibrary.csproj
+++ b/src/SarcLibrary/SarcLibrary.csproj
@@ -22,7 +22,8 @@
 	</ItemGroup>
 
 	<ItemGroup>
-	  <PackageReference Include="Revrs" Version="1.0.3" />
+	  <PackageReference Include="CommunityToolkit.HighPerformance" Version="8.2.2" />
+	  <PackageReference Include="Revrs" Version="1.0.4" />
 	</ItemGroup>
 
 </Project>
diff --git a/src/SarcLibrary/Writers/SfatWriter.cs b/src/SarcLibrary/Writers/SfatWriter.cs
index dfa5f90..f162652 100644
--- a/src/SarcLibrary/Writers/SfatWriter.cs
+++ b/src/SarcLibrary/Writers/SfatWriter.cs
@@ -8,7 +8,7 @@ internal class SfatWriter
     private const uint HASH_KEY = 0x65;
     private const ushort HEADER_SIZE = 0xC;
 
-    public static void Write(RevrsWriter writer, SarcNodeData[] entries, bool isHashOnly)
+    public static void Write(ref RevrsWriter writer, Span<SarcNodeData> entries, bool isHashOnly)
     {
         SfatHeader header = new() {
             Magic = Sarc.SFAT_MAGIC,
@@ -29,7 +29,7 @@ public static void Write(RevrsWriter writer, SarcNodeData[] entries, bool isHash
                 FileNameHash = entry.Value.FileNameHash,
                 FileAttributes = isHashOnly ? 0x0 : 0x01000000 | (nameOffset / 4),
                 DataStartOffset = dataOffset += dataOffset.AlignUp(entry.Value.Alignment),
-                DataEndOffset = dataOffset += entry.Value.Data.Length
+                DataEndOffset = dataOffset += entry.Value.Data.Count
             };
 
             nameOffset += entry.Name.Length + 1;
diff --git a/src/SarcLibrary/Writers/SfntWriter.cs b/src/SarcLibrary/Writers/SfntWriter.cs
index 40e8be9..1768637 100644
--- a/src/SarcLibrary/Writers/SfntWriter.cs
+++ b/src/SarcLibrary/Writers/SfntWriter.cs
@@ -6,7 +6,7 @@ namespace SarcLibrary.Writers;
 
 public class SfntWriter
 {
-    public unsafe static void Write(RevrsWriter writer, SarcNodeData[] entries)
+    public unsafe static void Write(ref RevrsWriter writer, Span<SarcNodeData> entries)
     {
         SfntHeader header = new() {
             Magic = Sarc.SFNT_MAGIC,