Fix errors when parsing audio

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

packages/wolf_3d_data/lib/src/wl_parser.dart

@@ -62,7 +62,7 @@ abstract class WLParser {
   }) {
     final isShareware = version == GameVersion.shareware;
 
-    final audio = parseAudio(audioHed, audioT);
+    final audio = parseAudio(audioHed, audioT, version);
 
     return WolfensteinData(
       version: version,
@@ -295,9 +295,9 @@ abstract class WLParser {
   static ({List<AdLibSound> adLib, List<ImfMusic> music}) parseAudio(
     ByteData audioHed,
     ByteData audioT,
+    GameVersion version,
   ) {
     List<int> offsets = [];
-    // AUDIOHED is a series of 32-bit unsigned integers
     for (int i = 0; i < audioHed.lengthInBytes ~/ 4; i++) {
       offsets.add(audioHed.getUint32(i * 4, Endian.little));
     }
@@ -308,7 +308,6 @@ abstract class WLParser {
       int start = offsets[i];
       int next = offsets[i + 1];
 
-      // 0xFFFFFFFF (or 4294967295) marks an empty slot
       if (start == 0xFFFFFFFF || start >= audioT.lengthInBytes) {
         allAudioChunks.add(Uint8List(0));
         continue;
@@ -324,16 +323,18 @@ abstract class WLParser {
       }
     }
 
-    // Wolfenstein 3D split:
-    // Chunks 0-299: AdLib Sounds
-    // Chunks 300+: IMF Music
+    // --- THE FIX: Accurate Historical Chunk Indices ---
+    // WL1 (Shareware) has exactly 234 sound effects before the music.
+    // WL6 (Retail) has exactly 261 sound effects before the music.
+    int musicStartIndex = (version == GameVersion.shareware) ? 234 : 261;
+
     List<AdLibSound> adLib = allAudioChunks
-        .take(300)
+        .take(musicStartIndex)
         .map((bytes) => AdLibSound(bytes))
         .toList();
 
     List<ImfMusic> music = allAudioChunks
-        .skip(300)
+        .skip(musicStartIndex)
         .where((chunk) => chunk.isNotEmpty)
         .map((bytes) => ImfMusic.fromBytes(bytes))
         .toList();