refactor(backend): return AudioTranscodeResult with status code and duration

backend/Musify.Application/Contracts/AudioTranscodeResult.cs

@@ -0,0 +1,4 @@
+namespace Musify.Application.Contracts
+{
+    public record AudioTranscodeResult(int StatusCode, TimeSpan Duration);
+}

backend/Musify.Application/Contracts/IAudioTranscoderService.cs

@@ -2,7 +2,7 @@ namespace Musify.Application.Contracts
 {
     public interface IAudioTranscoderService
     {
-        Task<TimeSpan> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken);
+        Task<AudioTranscodeResult> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken);
 
         Task<bool> IsValidAudioFileAsync(string filePath, CancellationToken cancellationToken);
     }

backend/Musify.Infrastructure/MassTransit/Activities/Audio/TranscodeAudioActivity.cs

@@ -38,21 +38,24 @@ namespace Musify.Infrastructure.MassTransit.Activities.Audio
 
             try
             {
-                TimeSpan duration;
+                AudioTranscodeResult transcodeResult;
                 await using (var fileStream = File.OpenRead(sourceFilePath))
                 {
-                    duration = await audioTranscoder.TranscodeToAudioFileAsync(
+                    transcodeResult = await audioTranscoder.TranscodeToAudioFileAsync(
                         fileStream,
                         workingDirectory,
                         executeContext.CancellationToken);
                 }
 
+                if (transcodeResult.StatusCode != 0)
+                    throw new InvalidOperationException($"ffmpeg transcoding failed with exit code {transcodeResult.StatusCode}.");
+
                 File.Delete(sourceFilePath);
 
                 var log = new TranscodeAudioLog(workingDirectory);
                 return executeContext.CompletedWithVariables(log, new Dictionary<string, object>
                 {
-                    [RoutingSlipVariableNames.Audio.DurationSeconds] = (int)Math.Round(duration.TotalSeconds)
+                    [RoutingSlipVariableNames.Audio.DurationSeconds] = (int)Math.Round(transcodeResult.Duration.TotalSeconds)
                 } );
             }
             catch (Exception exception)

backend/Musify.Infrastructure/Services/AudioTranscoderService.cs

@@ -16,7 +16,7 @@ namespace Musify.Infrastructure.Services
         [GeneratedRegex(@"Duration:\s*(\d+):(\d{2}):(\d{2}(?:\.\d+)?)", RegexOptions.IgnoreCase)]
         private static partial Regex DurationRegex();
 
-        public async Task<TimeSpan> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken)
+        public async Task<AudioTranscodeResult> TranscodeToAudioFileAsync(Stream audioStream, string destinationPath, CancellationToken cancellationToken)
         {
             try
             {
@@ -35,13 +35,14 @@ namespace Musify.Infrastructure.Services
                 {
                     logger.LogError("Audio transcoding failed with exit code {ExitCode}. Output: {StandardOutput}, Error: {StandardError}",
                         executionResult.ExitCode, executionResult.StandardOutput, executionResult.StandardError);
-                    throw new InvalidOperationException($"ffmpeg transcoding failed with exit code {executionResult.ExitCode}.");
+                    return new AudioTranscodeResult(executionResult.ExitCode, TimeSpan.Zero);
                 }
 
                 logger.LogInformation("Audio transcoding completed for {DestinationPath}", destinationPath);
 
                 var outputPath = Path.Combine(destinationPath, audioTranscoderConfiguration.Ffmpeg.OutputFileName);
-                return await GetAudioDurationAsync(outputPath, cancellationToken);
+                var duration = await GetAudioDurationAsync(outputPath, cancellationToken);
+                return new AudioTranscodeResult(executionResult.ExitCode, duration);
             }
             catch (TimeoutException timeoutException)
             {