WIP: improve Linux audio support

src/engine/audio.rs

@@ -237,6 +237,12 @@ pub struct AudioStreamConfig {
     pub max_voices: usize,
 }
 
+pub struct AudioStreamInfo {
+    pub sample_rate: f32,
+    pub host_name: String,
+    pub channels: u16,
+}
+
 pub fn build_stream(
     config: &AudioStreamConfig,
     audio_rx: Receiver<AudioCommand>,
@@ -245,7 +251,7 @@ pub fn build_stream(
     metrics: Arc<EngineMetrics>,
     initial_samples: Vec<doux::sampling::SampleEntry>,
     audio_sample_pos: Arc<AtomicU64>,
-) -> Result<(Stream, f32, AnalysisHandle), String> {
+) -> Result<(Stream, AudioStreamInfo, AnalysisHandle), String> {
     let device = match &config.output_device {
         Some(name) => doux::audio::find_output_device(name)
             .ok_or_else(|| format!("Device not found: {name}"))?,
@@ -258,11 +264,8 @@ pub fn build_stream(
     let max_channels = doux::audio::max_output_channels(&device);
     let channels = config.channels.min(max_channels);
 
-    let is_jack = doux::audio::preferred_host()
-        .id()
-        .name()
-        .to_lowercase()
-        .contains("jack");
+    let host_name = doux::audio::preferred_host().id().name().to_string();
+    let is_jack = host_name.to_lowercase().contains("jack");
 
     let buffer_size = if config.buffer_size > 0 && !is_jack {
         cpal::BufferSize::Fixed(config.buffer_size)
@@ -277,6 +280,7 @@ pub fn build_stream(
     };
 
     let sr = sample_rate;
+    let effective_channels = channels;
     let channels = channels as usize;
     let max_voices = config.max_voices;
 
@@ -347,5 +351,10 @@ pub fn build_stream(
     stream
         .play()
         .map_err(|e| format!("Failed to play stream: {e}"))?;
-    Ok((stream, sample_rate, analysis_handle))
+    let info = AudioStreamInfo {
+        sample_rate,
+        host_name,
+        channels: effective_channels,
+    };
+    Ok((stream, info, analysis_handle))
 }