Smarter asset loading. Better audio rendering.

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

packages/wolf_3d_data/lib/src/wolfenstein_loader.dart

@@ -23,30 +23,53 @@ class WolfensteinLoader {
     );
   }
 
-  /// Parses WolfensteinData directly from raw ByteData.
-  /// This is 100% pure Dart and is safe to use on all platforms, including Web.
+  /// Parses WolfensteinData from raw ByteData.
+  /// Throws an [ArgumentError] if any required file is null.
   static WolfensteinData loadFromBytes({
     required GameVersion version,
-    required ByteData vswap,
-    required ByteData mapHead,
-    required ByteData gameMaps,
-    required ByteData vgaDict,
-    required ByteData vgaHead,
-    required ByteData vgaGraph,
-    required ByteData audioHed,
-    required ByteData audioT,
+    required ByteData? vswap,
+    required ByteData? mapHead,
+    required ByteData? gameMaps,
+    required ByteData? vgaDict,
+    required ByteData? vgaHead,
+    required ByteData? vgaGraph,
+    required ByteData? audioHed,
+    required ByteData? audioT,
   }) {
-    // We just act as a clean pass-through to the core parser
+    // 1. Validation Check
+    final Map<String, ByteData?> files = {
+      'VSWAP': vswap,
+      'MAPHEAD': mapHead,
+      'GAMEMAPS': gameMaps,
+      'VGADICT': vgaDict,
+      'VGAHEAD': vgaHead,
+      'VGAGRAPH': vgaGraph,
+      'AUDIOHED': audioHed,
+      'AUDIOT': audioT,
+    };
+
+    final missing = files.entries
+        .where((e) => e.value == null)
+        .map((e) => "${e.key}.${version.fileExtension}")
+        .toList();
+
+    if (missing.isNotEmpty) {
+      throw ArgumentError(
+        'Cannot load ${version.name}: Missing files: ${missing.join(", ")}',
+      );
+    }
+
+    // 2. Pass-through to parser now that we are guaranteed non-null
     return WLParser.load(
       version: version,
-      vswap: vswap,
-      mapHead: mapHead,
-      gameMaps: gameMaps,
-      vgaDict: vgaDict,
-      vgaHead: vgaHead,
-      vgaGraph: vgaGraph,
-      audioHed: audioHed,
-      audioT: audioT,
+      vswap: vswap!,
+      mapHead: mapHead!,
+      gameMaps: gameMaps!,
+      vgaDict: vgaDict!,
+      vgaHead: vgaHead!,
+      vgaGraph: vgaGraph!,
+      audioHed: audioHed!,
+      audioT: audioT!,
     );
   }
 }