refactor: creating an AudioHandler instead of directly giving the thread, allowing to add custom event handlers while playback.

src/main.rs

@@ -11,7 +11,7 @@ use std::env;
 use std::sync::{Arc, Mutex};
 
 use dotenvy::dotenv;
-use vbplay::{AudioThread, DeviceSelection, SoundDecoder};
+use vbplay::{example_handler, AudioThread, DeviceSelection, PlaybackAction, SoundDecoder};
 
 mod soundclips;
 mod state;
@@ -28,11 +28,13 @@ async fn main() {
     jinja.set_loader(path_loader("templates"));
     let template_engine = Engine::from(jinja);
 
-    let audio = vbplay::audio_thread(
+    let mut audio = vbplay::AudioHandler::new(
         DeviceSelection::FindByPattern(device_pattern),
         SoundDecoder::Detect,
     );
-    let audio: Arc<Mutex<AudioThread>> = Arc::new(Mutex::new(audio));
+    let event_handler = Box::new(example_handler::PressMouseForward::new());
+    audio.on_playback(event_handler);
+    let audio = Arc::new(Mutex::new(audio));
 
     let app_state = AppState {
         engine: template_engine,
@@ -88,6 +90,7 @@ async fn play_handler(
         player
             .lock()
             .unwrap()
+            .listener
             .send(vbplay::Command::PlayWhilePressing(
                 full_file_name.into(),
                 "".to_owned(), // placeholder.
@@ -99,7 +102,12 @@ async fn play_handler(
 
 async fn stop_handler(state: State<AppState>) -> String {
     let player = state.player.clone();
-    player.lock().unwrap().send(vbplay::Command::Stop).unwrap();
+    player
+        .lock()
+        .unwrap()
+        .listener
+        .send(vbplay::Command::Stop)
+        .unwrap();
 
     "".to_owned()
 }

src/state.rs

@@ -1,5 +1,5 @@
 use crate::soundclips::SoundClip;
-use crate::vbplay::AudioThread;
+use crate::vbplay::AudioHandler;
 use axum::extract::FromRef;
 use axum_template::engine::Engine;
 use minijinja::Environment;
@@ -11,8 +11,8 @@ pub type TemplateEngine = Engine<Environment<'static>>;
 pub struct AppState {
     pub engine: TemplateEngine,
     pub clips: Vec<SoundClip>,
-    pub player: Arc<Mutex<AudioThread>>,
+    pub player: Arc<Mutex<AudioHandler>>,
-    pub playback: Option<Arc<Mutex<AudioThread>>>,
+    pub playback: Option<Arc<Mutex<AudioHandler>>>,
 }
 
 impl FromRef<AppState> for TemplateEngine {

src/vbplay.rs

@@ -71,19 +71,100 @@ fn select_device_by_id(index: usize) -> Option<Device> {
 
 pub type AudioThread = Sender<Command>;
 
-pub fn audio_thread(select_device: DeviceSelection, select_decoder: SoundDecoder) -> AudioThread {
+pub trait PlaybackAction {
+    fn before_playback(&mut self);
+    fn after_playback(&mut self);
+}
+
+pub struct PlaybackActionEvents {
+    actions: Vec<Box<dyn PlaybackAction + Send>>,
+}
+
+impl PlaybackActionEvents {
+    pub fn new() -> Self {
+        PlaybackActionEvents {
+            actions: Vec::new(),
+        }
+    }
+
+    pub fn dispatch_before_playback(&mut self) {
+        for action in self.actions.iter_mut() {
+            action.before_playback();
+        }
+    }
+
+    pub fn dispatch_after_playback(&mut self) {
+        for action in self.actions.iter_mut() {
+            action.after_playback();
+        }
+    }
+}
+
+pub struct AudioHandler {
+    pub listener: AudioThread,
+    events: Arc<Mutex<PlaybackActionEvents>>,
+}
+
+impl AudioHandler {
+    pub fn new(select_device: DeviceSelection, select_decoder: SoundDecoder) -> Self {
+        let events = Arc::new(Mutex::new(PlaybackActionEvents::new()));
+        let tx = audio_thread(select_device, select_decoder, events.clone());
+        Self {
+            listener: tx,
+            events,
+        }
+    }
+
+    pub fn on_playback(&mut self, event: Box<dyn PlaybackAction + Send>) {
+        self.events.lock().unwrap().actions.push(event);
+    }
+}
+
+pub mod example_handler {
+    use enigo::*;
+
+    pub struct PressMouseForward {
+        enigo: Enigo,
+    }
+
+    impl PressMouseForward {
+        pub fn new() -> Self {
+            let enigo = Enigo::new();
+            PressMouseForward { enigo: enigo }
+        }
+    }
+
+    impl super::PlaybackAction for PressMouseForward {
+        fn before_playback(&mut self) {
+            self.enigo.mouse_down(MouseButton::Forward);
+        }
+
+        fn after_playback(&mut self) {
+            self.enigo.mouse_up(MouseButton::Forward);
+        }
+    }
+}
+
+pub fn audio_thread(
+    select_device: DeviceSelection,
+    select_decoder: SoundDecoder,
+    events: Arc<Mutex<PlaybackActionEvents>>,
+) -> AudioThread {
     let (tx, rx) = mpsc::channel();
 
     thread::spawn(move || {
         let device = match select_device {
-            DeviceSelection::SelectFirst => select_device_by_id(0).unwrap(),
+            DeviceSelection::SelectFirst => {
-            DeviceSelection::SelectById(id) => select_device_by_id(id).unwrap(),
+                select_device_by_id(0).expect("No Audio devices found.")
-            DeviceSelection::FindByPattern(pattern) => {
-                select_device_by_pattern(pattern.as_ref()).unwrap()
             }
+            DeviceSelection::SelectById(id) => {
+                select_device_by_id(id).expect("Audio device for ID not found.")
+            }
+            DeviceSelection::FindByPattern(pattern) => select_device_by_pattern(pattern.as_ref())
+                .expect("Pattern search for audio device yielded no results."),
         };
 
-        // Create a rodio Sink connected to our device
+        // Create a rodio Sink connected to our device. We need to keep stream and stream_handle alive during the thread.
         let (_stream, stream_handle) = rodio::OutputStream::try_from_device(&device).unwrap();
         let new_sink = rodio::Sink::try_new(&stream_handle).unwrap();
 
@@ -109,16 +190,16 @@ pub fn audio_thread(select_device: DeviceSelection, select_decoder: SoundDecoder
                     if !is_button_thread_active.load(Ordering::SeqCst) {
                         let sink_mutex_clone = sink_mutex.clone();
                         let is_active_clone = is_button_thread_active.clone();
+                        let events_clone = events.clone();
                         thread::spawn(move || {
-                            let mut enigo = Enigo::new();
+                            events_clone.lock().unwrap().dispatch_before_playback();
-                            enigo.mouse_down(MouseButton::Forward);
                             is_active_clone.store(true, Ordering::SeqCst);
 
                             while sink_mutex_clone.lock().map_or(false, |sink| !sink.empty()) {
                                 thread::sleep(std::time::Duration::from_millis(100));
                             }
 
-                            enigo.mouse_up(MouseButton::Forward);
+                            events_clone.lock().unwrap().dispatch_after_playback();
                             is_active_clone.store(false, Ordering::SeqCst);
                         });
                     }