Add a missing instruction, and a testcase

lib/utils/uuid/NbtUUID.dart

@@ -13,6 +13,7 @@ class NbtUUID {
   factory NbtUUID.fromUUID(UUID id) {
     ByteLayer layer = ByteLayer();
     layer.writeBytes(id.getBytes());
+    layer.resetPosition();
 
     int MSB = layer.readLong();
     int LSB = layer.readLong();
@@ -27,191 +28,15 @@ class NbtUUID {
   int getLeastSignificantBits() => LSB;
 
   UUID toUUID() {
-    ByteLayer layer = ByteLayer();
-    layer.writeUnsignedLong(MSB);
-    layer.writeUnsignedLong(LSB);
-
-    return UUID(layer.readBytes(16));
-  }
-}
-
-/*
-class NbtUUID extends UUID{
-  late final int LSB;
-  late final int MSB;
-  late final List<int> _bytes;
-
-  NbtUUID(int msb, int lsb) {
-    MSB = msb;
-    LSB = lsb;
-
     ByteLayer layer = ByteLayer();
     layer.writeLong(MSB);
     layer.writeLong(LSB);
-    layer.resetPosition();
 
-    _bytes = layer.readBytes(16);
+    return UUID(layer.readBytes(16));
-  }
-
-  static final UUID ZERO = UUID.generate(0);
-
-  /// Validates whether the given [uuid] is a valid UUID.
-  static bool validate(String uuid) {
-    if (uuid.length == ((16 * 2) + 4)) {
-      return true; // Likely is true. This is just a surface level check
-    } else {
-      return false;
-    }
-  }
-
-  /// Parses the given [uuid] string and returns a UUID object.
-  static UUID parse(String uuid) {
-    if (validate(uuid)) {
-      final segments = uuid.split('-');
-      if (segments.length != 5) {
-        throw const FormatException('Invalid UUID format');
-      }
-
-      final msbString = segments.sublist(0, 3).join('');
-      final lsbString = segments.sublist(3, 5).join('');
-
-      int msb = 0;
-      int lsb = 0;
-
-      int i = 0;
-      ByteLayer layer = ByteLayer();
-      for (i = 0; i < msbString.length; i += 2) {
-        String hex = msbString.substring(i, i + 2);
-        int byte = int.parse(hex, radix: 16);
-        layer.writeByte(byte);
-      }
-
-      for (i = 0; i < lsbString.length; i += 2) {
-        String hex = lsbString.substring(i, i + 2);
-        int byte = int.parse(hex, radix: 16);
-        layer.writeByte(byte);
-      }
-
-      layer.resetPosition();
-      msb = layer.readLong();
-      lsb = layer.readLong();
-
-      return UUID(msb, lsb);
-    } else {
-      return UUID.ZERO;
-    }
   }
 
   @override
   String toString() {
-    String hexBuilder = "";
+    return toUUID().toString();
-    for (int byte in _bytes) {
-      hexBuilder += byte.toRadixString(16).padLeft(2, '0');
-    }
-    return '${hexBuilder.substring(0, 8)}-${hexBuilder.substring(8, 12)}-${hexBuilder.substring(12, 16)}-${hexBuilder.substring(16, 20)}-${hexBuilder.substring(20, 32)}';
-  }
-
-  /// Returns the Most Significant Bits (MSB) long value of the UUID.
-  int getMostSignificantBits() => MSB;
-
-  /// Returns the Least Significant Bits (LSB) long value of the UUID.
-  int getLeastSignificantBits() => LSB;
-
-  /// Factory method to generate UUID of the specific version.
-  factory UUID.generate(int version, {List<Object>? parameters}) {
-    List<Object> params = [];
-    if (parameters == null) {
-      if (version != 4 && version != 0) {
-        return UUID.generate(4);
-      }
-    } else {
-      params = parameters;
-    }
-    switch (version) {
-      case 0:
-        return UUID(0, 0);
-      case 3:
-        {
-          if (params.length != 2) {
-            throw Exception(
-                "UUID v3 requires two parameters, [namespace,name]");
-          }
-          String namespace = params[0] as String;
-          String name = params[1] as String;
-
-          ByteLayer layer = ByteLayer();
-
-          final namespaceBytes = utf8.encode(namespace);
-          layer.writeBytes(namespaceBytes);
-          final nameBytes = utf8.encode(name);
-          layer.writeBytes(nameBytes);
-
-          var bytes = md5.convert(List.from(layer.bytes)).bytes;
-          layer.clear();
-          layer.writeBytes(bytes);
-
-          layer.unsetSetBit(6, 0xF0, 0x30);
-          layer.unsetSetBit(8, 0xC0, 0x80);
-
-          layer.resetPosition();
-
-          var msb = layer.readUnsignedLong();
-          var lsb = layer.readUnsignedLong();
-
-          layer.resetPosition();
-          return UUID(msb, lsb);
-        }
-      case 4:
-        {
-          ByteLayer layer = ByteLayer();
-          final random = Random.secure();
-
-          layer.writeLong(
-              (random.nextInt(0xFFFFFFFF) << 32) | random.nextInt(0xFFFFFFFF));
-          layer.writeLong(
-              (random.nextInt(0xFFFFFFFF) << 32) | random.nextInt(0xFFFFFFFF));
-
-          layer.unsetSetBit(6, 0xF0, 0x40);
-          layer.unsetSetBit(8, 0xC0, 0x80);
-
-          layer.resetPosition();
-
-          return UUID(layer.readUnsignedLong(), layer.readUnsignedLong());
-        }
-      case 5:
-        {
-          ByteLayer layer = ByteLayer();
-          if (params.length != 2) {
-            throw Exception(
-                "UUID v5 requires two parameters, [namespace,name]");
-          }
-          String namespace = params[0] as String;
-          String name = params[1] as String;
-
-          if (namespace.isNotEmpty) {
-            final namespaceBytes = utf8.encode(namespace);
-            layer.writeBytes(namespaceBytes);
-          }
-
-          if (name.isNotEmpty) {
-            final nameBytes = utf8.encode(name);
-            layer.writeBytes(nameBytes);
-          }
-
-          final hashBytes = sha1.convert(List.from(layer.bytes)).bytes;
-          layer.clear();
-          layer.writeBytes(hashBytes);
-
-          layer.unsetSetBit(6, 0xF0, 0x50);
-          layer.unsetSetBit(8, 0xC0, 0x80);
-
-          layer.resetPosition();
-
-          return UUID(layer.readUnsignedLong(), layer.readUnsignedLong());
-        }
-      default:
-        throw ArgumentError('Unsupported UUID version: $version');
   }
 }
-}
-*/

test/nbt_test.dart

@@ -86,4 +86,13 @@ void main() {
     // Expect that the file exists
     expect(file.existsSync(), true);
   });
+
+  test("Write NULL UUID to NBT", () async {
+    CompoundTag tag = CompoundTag();
+    NbtUtils.writeUUID(tag, "test", NbtUUID.fromUUID(UUID.ZERO));
+    NbtUUID ID = NbtUtils.readUUID(tag, "test");
+
+    expect(ID.MSB, 0);
+    expect(ID.LSB, 0);
+  });
 }