Warn when AWC names collide in the first 8 characters

The game identifies a wavepack by the first 8 characters of its name (RAGE truncates
them; visible in FiveM's PatchAudioWavePackOverlay 8-char base-pack match). Two AWCs
that match in the first 8 chars resolve to the same bank, so one loads and the rest go
silent. Preflight now warns on that collision (no length enforcement - a long but
8-char-unique name is fine).

Author: BJDubb

SirenSharp.Tests/PreflightServiceTests.cs

@@ -21,6 +21,32 @@ public void EmptyProject_IsBlockingError()
             Assert.Contains(report.Items, d => d.Code == DiagnosticCodes.ProjectEmpty);
         }
 
+        [Fact]
+        public void AwcNamesSharingFirst8Chars_WarnCollision()
+        {
+            using var dir = new TempDir();
+            var project = new Project("demo", dir.File("demo.ssproj"));
+            // Distinct names, but identical in the first 8 chars -> same wavepack in-game.
+            project.SoundSets.Add(new SoundSet("policecar1"));
+            project.SoundSets.Add(new SoundSet("policecar2"));
+
+            var report = Preflight.Inspect(project);
+            Assert.Contains(report.Warnings, d => d.Code == DiagnosticCodes.AwcNameCollision);
+        }
+
+        [Fact]
+        public void AwcNamesDifferingWithin8Chars_NoCollision()
+        {
+            using var dir = new TempDir();
+            var project = new Project("demo", dir.File("demo.ssproj"));
+            project.SoundSets.Add(new SoundSet("lspd"));
+            project.SoundSets.Add(new SoundSet("bcso"));
+            project.SoundSets.Add(new SoundSet("fire_dept")); // 9 chars but unique in 8 -> fine
+
+            var report = Preflight.Inspect(project);
+            Assert.DoesNotContain(report.Items, d => d.Code == DiagnosticCodes.AwcNameCollision);
+        }
+
         [Fact]
         public void DuplicateSoundsetNames_AreBlockingError()
         {

SirenSharp/Models/Diagnostic.cs

@@ -46,6 +46,7 @@ public static class DiagnosticCodes
         public const string AwcDuplicateName = "AWC.DUPLICATE_NAME";
         public const string AwcInvalidName = "AWC.INVALID_NAME";
         public const string AwcNoSirens = "AWC.NO_SIRENS";
+        public const string AwcNameCollision = "AWC.NAME_COLLISION";
         public const string SirenDuplicateName = "SIREN.DUPLICATE_NAME";
         public const string SirenInvalidName = "SIREN.INVALID_NAME";
         public const string SirenMissingFile = "SIREN.MISSING_FILE";

SirenSharp/Services/Preflight/PreflightChecks.cs

@@ -33,6 +33,26 @@ public IEnumerable<Diagnostic> Inspect(Project project)
                     DiagnosticCodes.AwcDuplicateName,
                     name);
             }
+
+            // The game identifies wavepacks (AWCs) by the first 8 characters of the name only
+            // (RAGE truncates them; see FiveM's PatchAudioWavePackOverlay 8-char match). Two AWCs
+            // whose names match in the first 8 chars resolve to the same bank, so only one loads
+            // and the other plays silent in-game - even though both names look distinct here.
+            var prefixCollisions = project.SoundSets
+                .Where(s => !string.IsNullOrEmpty(s.Name))
+                .GroupBy(s => s.Name.ToLowerInvariant().Substring(0, Math.Min(8, s.Name.Length)))
+                .Where(g => g.Select(s => s.Name).Distinct().Count() > 1);
+
+            foreach (var group in prefixCollisions)
+            {
+                var names = string.Join(", ", group.Select(s => s.Name).Distinct());
+                yield return new Diagnostic(
+                    DiagnosticSeverity.Warning,
+                    $"AWCs {names} share the same first 8 characters ('{group.Key}'). The game uses only the first 8 characters to identify a wavepack, so these resolve to the same bank - only one will load and the others will be silent in-game.",
+                    DiagnosticCodes.AwcNameCollision,
+                    group.Key,
+                    "Make the first 8 characters of each AWC name unique.");
+            }
         }
     }