Expose origin BoM and TextEncoding

src/MessageStudio/Formats/BinaryText/ImmutableMsbt.cs

@@ -2,12 +2,12 @@
 using MessageStudio.Formats.BinaryText.Structures;
 using MessageStudio.IO;
 using System.Runtime.CompilerServices;
-using System.Text;
 
 namespace MessageStudio.Formats.BinaryText;
 
 public readonly ref struct ImmutableMsbt
 {
+    public readonly MsbtHeader Header;
     public readonly AttributeSectionReader AttributeSectionReader;
     public readonly LabelSectionReader LabelSectionReader;
     public readonly TextSectionReader TextSectionReader;
@@ -46,5 +46,15 @@ public ImmutableMsbt(ref SpanReader reader)
 
             reader.Align(0x10);
         }
+
+        Header = header;
+
+        // Fix the BoM for consumers
+        unsafe {
+            fixed (Endian* ptr = &Header.ByteOrderMark) {
+                Span<byte> range = new(ptr, sizeof(Endian));
+                range.Reverse();
+            }
+        }
     }
 }

src/MessageStudio/Formats/BinaryText/Msbt.cs

@@ -13,6 +13,9 @@ public class Msbt : Dictionary<string, MsbtEntry>
     internal const uint LBL1_MAGIC = 0x314C424C;
     internal const uint TXT2_MAGIC = 0x32545854;
 
+    public Endian Endian { get; set; } = Endian.Little;
+    public TextEncoding Encoding { get; set; } = TextEncoding.Unicode;
+
     /// <summary>
     /// Create a new <see cref="Msbt"/> object from a data buffer
     /// </summary>
@@ -32,7 +35,11 @@ public static Msbt FromBinary(Span<byte> buffer)
     /// <returns></returns>
     public static Msbt FromImmutable(ref ImmutableMsbt msbt)
     {
-        Msbt managed = [];
+        Msbt managed = new() {
+            Encoding = msbt.Header.Encoding,
+            Endian = msbt.Header.ByteOrderMark
+        };
+
         foreach (var label in msbt.LabelSectionReader) {
             int index = label.Index;
             string? key = label.GetManaged();