audio: move audio task into separate audio module

src/audio.rs

@@ -0,0 +1,88 @@
+use jack::{AudioIn, ClientOptions};
+use oximedia_metering::vu_meter::VuMeter;
+use tokio::sync::*;
+
+#[derive(Debug)]
+pub struct JackClientRef {
+    killswitch: Option<oneshot::Sender<()>>
+}
+
+impl Drop for JackClientRef {
+    fn drop(&mut self) {
+        self.killswitch.take().unwrap().send(()).unwrap();
+    }
+}
+
+#[derive(Debug)]
+pub struct AudioInputControl {
+    volume_src: watch::Receiver<f64>,
+    _jack_client: JackClientRef
+}
+
+impl AudioInputControl {
+    pub async fn next(&mut self) -> f64 {
+        self.volume_src.changed().await.unwrap();
+        *self.volume_src.borrow_and_update()
+    }
+}
+
+#[derive(Debug)]
+pub struct MicStream {
+    pub src: mpsc::Receiver<Vec<f32>>,
+    pub sample_rate: u32
+}
+
+pub async fn start_audio_input(messages: &mpsc::Sender<String>) -> (AudioInputControl, MicStream) {
+
+    let (exit_tx, exit_rx) = oneshot::channel();
+
+    let (mic_audio_sink, mic_audio_src) = mpsc::channel(32);
+    let (volume_sink, volume_src) = watch::channel(0.);
+
+    let (client, _status) = jack::Client::new("Eva-Cohost", ClientOptions::default() | ClientOptions::SESSION_ID).unwrap();
+    let mic_port = client.register_port("microphone-in", AudioIn::default()).unwrap();
+    let rate = client.sample_rate();
+
+    if let Ok(_) = client.connect_ports_by_name("mixxx-mic-1:capture_MONO", mic_port.name().unwrap().as_str()) {
+        messages.send("Connected to audio.".into()).await.unwrap();
+    } else {
+        messages.send("Failed to reconnect to audio.".into()).await.unwrap();
+    }
+
+    let mut meter = VuMeter::new(rate.into(), 1, None);
+
+    let handler = jack::contrib::ClosureProcessHandler::new(move |_client, scope| {
+        if mic_port.connected_count().unwrap() > 0 {
+            let buf: Vec<_> = mic_port.as_slice(scope).iter().copied().collect();
+            meter.process_interleaved(&buf);
+            mic_audio_sink.blocking_send(buf).unwrap();
+
+            volume_sink.send_if_modified(|v| {
+                let next_vu = meter.channel_vu(0).unwrap();
+                if *v != next_vu {
+                    *v = next_vu;
+                    true
+                } else {
+                    false
+                }
+            });
+        }
+        jack::Control::Continue
+    });
+
+    tokio::spawn(async move {
+        let async_client = client.activate_async((), handler).unwrap();
+
+        exit_rx.await.unwrap();
+
+        async_client.deactivate().unwrap();
+    });
+
+    (AudioInputControl {
+        volume_src,
+        _jack_client: JackClientRef { killswitch: Some(exit_tx) }
+    }, MicStream {
+        sample_rate: rate,
+        src: mic_audio_src
+    })
+}