♻️ refactor: extract DecoderThread and clean up identifiers

src/main.rs

@@ -102,7 +102,7 @@ pub struct SharedState {
 	pub quit: bool,
 }
 
-fn cmd_gui (args: &[String]) -> Result <()> {
+fn cmd_gui (_args: &[String]) -> Result <()> {
 	let (fltk_tx, fltk_rx) = app::channel::<Message> ();
 	
 	let app = app::App::default ();
@@ -151,59 +151,19 @@ fn cmd_play (args: &[String]) -> Result <()> {
 	.map (|s| s.to_string ())
 	.collect ();
 	
-	let pair = Arc::new ((Mutex::new (SharedState::default ()), Condvar::new ()));
-	let pair2 = Arc::clone (&pair);
-	let pair3 = Arc::clone (&pair);
-	
-	let thread_decoder = thread::spawn (move|| {
-		let (lock, cvar) = &*pair2;
-		
-		'many_files: for filename in &filenames {
-			let mut decoder = decoder::Decoder::new (&filename)?;
-			
-			'one_file: loop {
-				let frame = match decoder.next ()? {
-					Some (x) => x,
-					None => {
-						tracing::debug! ("Decoder thread finished a file");
-						break 'one_file;
-					},
-				};
-				
-				let mut decoder_state = cvar.wait_while (lock.lock ().unwrap (), |decoder_state| {
-					decoder_state.pcm_buffers.samples_available () >= 12_000 &&
-					! decoder_state.quit
-				}).unwrap ();
-				
-				if decoder_state.quit {
-					break 'many_files;
-				}
-				
-				decoder_state.pcm_buffers.produce_bytes (frame.data ().into ());
-			}
-		}
-		
-		Ok::<_, anyhow::Error> (())
-	});
-	
+	let shared_state = Arc::new ((Mutex::new (SharedState::default ()), Condvar::new ()));
 	let pcm_quit = Arc::new ((Mutex::new (false), Condvar::new ()));
-	let pcm_quit2 = Arc::clone (&pcm_quit);
 	
-	let audio_output = AudioOutput::new (pcm_quit, pair)?;
+	let thread_decoder = DecoderThread::new (Arc::clone (&shared_state), filenames);
+	let audio_output = AudioOutput::new (Arc::clone (&pcm_quit), Arc::clone (&shared_state))?;
 	
 	tracing::debug! ("Joining decoder thread...");
 	
-	if false {
-		let mut decoder_state = pair3.0.lock ().unwrap ();
-		decoder_state.quit = true;
-		pair3.1.notify_one ();
-	}
-	
-	thread_decoder.join ().unwrap ()?;
+	thread_decoder.join ()?;
 	
 	tracing::debug! ("Joining PCM thread...");
 	
-	let (lock, cvar) = &*pcm_quit2;
+	let (lock, cvar) = &*pcm_quit;
 	let _ = cvar.wait (lock.lock ().unwrap ()).unwrap ();
 	
 	drop (audio_output);
@@ -214,6 +174,57 @@ fn cmd_play (args: &[String]) -> Result <()> {
 	Ok (())
 }
 
+struct DecoderThread {
+	join_handle: thread::JoinHandle <Result <()>>,
+}
+
+impl DecoderThread {
+	pub fn new (
+		shared_state: Arc <(Mutex <SharedState>, Condvar)>,
+		filenames: Vec <String>,
+	) -> Self
+	{
+		let join_handle = thread::spawn (move|| {
+			let (lock, cvar) = &*shared_state;
+			
+			'many_files: for filename in &filenames {
+				let mut decoder = decoder::Decoder::new (&filename)?;
+				
+				'one_file: loop {
+					let frame = match decoder.next ()? {
+						Some (x) => x,
+						None => {
+							tracing::debug! ("Decoder thread finished a file");
+							break 'one_file;
+						},
+					};
+					
+					let mut decoder_state = cvar.wait_while (lock.lock ().unwrap (), |decoder_state| {
+						decoder_state.pcm_buffers.samples_available () >= 12_000 &&
+						! decoder_state.quit
+					}).unwrap ();
+					
+					if decoder_state.quit {
+						break 'many_files;
+					}
+					
+					decoder_state.pcm_buffers.produce_bytes (frame.data ().into ());
+				}
+			}
+			
+			Ok::<_, anyhow::Error> (())
+		});
+		
+		Self {
+			join_handle,
+		}
+	}
+	
+	pub fn join (self) -> Result <()> {
+		self.join_handle.join ().unwrap ()
+	}
+}
+
 struct AudioOutput {
 	host: cpal::Host,
 	device: cpal::Device,
@@ -223,8 +234,9 @@ struct AudioOutput {
 impl AudioOutput {
 	pub fn new (
 		pcm_quit: Arc <(Mutex <bool>, Condvar)>,
-		pair: Arc <(Mutex <SharedState>, Condvar)>,
-	) -> Result <Self> {
+		shared_state: Arc <(Mutex <SharedState>, Condvar)>,
+	) -> Result <Self> 
+	{
 		let host = cpal::default_host ();
 		let device = host.default_output_device ().ok_or_else (|| anyhow! ("can't open cpal device"))?;
 		
@@ -239,7 +251,7 @@ impl AudioOutput {
 		let stream = device.build_output_stream (
 			&config,
 			move |data: &mut [f32], _: &cpal::OutputCallbackInfo| {
-				let (lock, cvar) = &*pair;
+				let (lock, cvar) = &*shared_state;
 				
 				let time_start = Instant::now ();
 				let mut decoder_state = match lock.lock () {
@@ -281,6 +293,14 @@ impl AudioOutput {
 			stream,
 		})
 	}
+	
+	pub fn play (&mut self) -> Result <()> {
+		Ok (self.stream.play ()?)
+	}
+	
+	pub fn pause (&mut self) -> Result <()> {
+		Ok (self.stream.pause ()?)
+	}
 }
 
 #[cfg (test)]