consolidate and save to disk

Cargo.lock

@@ -125,6 +125,12 @@ version = "0.31.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "07e28edb80900c19c28f1072f2e8aeca7fa06b23cd4169cefe1af5aa3260783f"
 
+[[package]]
+name = "hound"
+version = "3.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62adaabb884c94955b19907d60019f4e145d091c75345379e70d1ee696f7854f"
+
 [[package]]
 name = "itoa"
 version = "1.0.15"
@@ -221,6 +227,7 @@ name = "looper"
 version = "0.1.0"
 dependencies = [
  "dirs",
+ "hound",
  "jack",
  "kanal",
  "log",

Cargo.toml

@@ -15,6 +15,7 @@ path = "src/sendmidi.rs"
 
 [dependencies]
 dirs = "5"
+hound = "3.5"
 jack = "0.13"
 kanal = "0.1"
 log = "0.4"

src/audio_chunk.rs

@@ -85,6 +85,19 @@ impl AudioChunk {
         }
     }
 
+    /// Get total sample count across entire chunk chain
+    pub fn len(&self) -> usize {
+        let mut total = self.sample_count;
+        let mut current = &self.next;
+        
+        while let Some(chunk) = current {
+            total += chunk.sample_count;
+            current = &chunk.next;
+        }
+        
+        total
+    }
+
     pub fn copy_samples(self: &Arc<Self>, dest: &mut [f32], start: usize) -> Result<()> {
         if start < self.sample_count {
             // Copy from this chunk
@@ -113,6 +126,123 @@ impl AudioChunk {
 mod tests {
     use super::*;
 
+    #[test]
+    fn test_len_single_chunk_with_samples() {
+        let chunk = Arc::new(AudioChunk {
+            samples: vec![1.0, 2.0, 3.0, 4.0, 5.0].into_boxed_slice(),
+            sample_count: 5,
+            next: None,
+        });
+
+        assert_eq!(chunk.len(), 5);
+    }
+
+    #[test]
+    fn test_len_single_chunk_empty() {
+        let chunk = Arc::new(AudioChunk {
+            samples: vec![0.0, 0.0, 0.0].into_boxed_slice(),
+            sample_count: 0,
+            next: None,
+        });
+
+        assert_eq!(chunk.len(), 0);
+    }
+
+    #[test]
+    fn test_len_single_chunk_partial() {
+        let chunk = Arc::new(AudioChunk {
+            samples: vec![1.0, 2.0, 3.0, 0.0, 0.0].into_boxed_slice(),
+            sample_count: 3, // Only first 3 samples are valid
+            next: None,
+        });
+
+        assert_eq!(chunk.len(), 3);
+    }
+
+    #[test]
+    fn test_len_linked_chunks() {
+        let chunk3 = Arc::new(AudioChunk {
+            samples: vec![7.0, 8.0, 9.0].into_boxed_slice(),
+            sample_count: 3,
+            next: None,
+        });
+
+        let chunk2 = Arc::new(AudioChunk {
+            samples: vec![4.0, 5.0].into_boxed_slice(),
+            sample_count: 2,
+            next: Some(chunk3),
+        });
+
+        let chunk1 = Arc::new(AudioChunk {
+            samples: vec![1.0, 2.0, 3.0].into_boxed_slice(),
+            sample_count: 3,
+            next: Some(chunk2),
+        });
+
+        assert_eq!(chunk1.len(), 8); // 3 + 2 + 3
+    }
+
+    #[test]
+    fn test_len_chain_with_empty_chunks() {
+        let chunk3 = Arc::new(AudioChunk {
+            samples: vec![4.0, 5.0].into_boxed_slice(),
+            sample_count: 2,
+            next: None,
+        });
+
+        let chunk2 = Arc::new(AudioChunk {
+            samples: vec![0.0, 0.0].into_boxed_slice(),
+            sample_count: 0, // Empty chunk in middle
+            next: Some(chunk3),
+        });
+
+        let chunk1 = Arc::new(AudioChunk {
+            samples: vec![1.0, 2.0, 3.0].into_boxed_slice(),
+            sample_count: 3,
+            next: Some(chunk2),
+        });
+
+        assert_eq!(chunk1.len(), 5); // 3 + 0 + 2
+    }
+
+    #[test]
+    fn test_len_all_empty_chunks() {
+        let chunk2 = Arc::new(AudioChunk {
+            samples: vec![0.0, 0.0].into_boxed_slice(),
+            sample_count: 0,
+            next: None,
+        });
+
+        let chunk1 = Arc::new(AudioChunk {
+            samples: vec![0.0, 0.0, 0.0].into_boxed_slice(),
+            sample_count: 0,
+            next: Some(chunk2),
+        });
+
+        assert_eq!(chunk1.len(), 0);
+    }
+
+    #[test]
+    fn test_len_long_chain() {
+        // Create a longer chain to test iteration
+        let mut current_chunk = Arc::new(AudioChunk {
+            samples: vec![10.0].into_boxed_slice(),
+            sample_count: 1,
+            next: None,
+        });
+
+        // Build chain backwards: 9 -> 8 -> ... -> 1 -> 0
+        for i in (0..10).rev() {
+            current_chunk = Arc::new(AudioChunk {
+                samples: vec![i as f32].into_boxed_slice(),
+                sample_count: 1,
+                next: Some(current_chunk),
+            });
+        }
+
+        assert_eq!(current_chunk.len(), 11); // 11 chunks, each with 1 sample
+    }
+
     #[test]
     fn test_allocate_creates_empty_chunk() {
         let chunk = AudioChunk::allocate(1024);

src/audio_engine.rs

@@ -6,9 +6,10 @@ mod looper_error;
 mod metronome;
 mod midi;
 mod notification_handler;
+mod post_record_handler;
 mod process_handler;
 mod state;
-mod state_manager;
+mod persistence_manager;
 mod track;
 
 use std::sync::Arc;
@@ -19,14 +20,18 @@ use chunk_factory::ChunkFactory;
 use connection_manager::ConnectionManager;
 use looper_error::LooperError;
 use looper_error::Result;
+use metronome::Metronome;
 use metronome::generate_beep;
 use notification_handler::JackNotification;
 use notification_handler::NotificationHandler;
+use post_record_handler::PostRecordHandler;
+use post_record_handler::PostRecordController;
 use process_handler::ProcessHandler;
 use state::State;
-use state_manager::StateManager;
+use persistence_manager::PersistenceManager;
 use track::Track;
 use track::TrackState;
+use track::TrackTiming;
 
 pub struct JackPorts {
     pub audio_in: jack::Port<jack::AudioIn>,
@@ -51,20 +56,25 @@ async fn main() {
     let notification_handler = NotificationHandler::new();
     let mut notification_channel = notification_handler.subscribe();
 
-    let (mut state_manager, state_rx) = StateManager::new(notification_handler.subscribe());
+    let (mut persistence_manager, state_watch) = PersistenceManager::new(notification_handler.subscribe());
 
     // Load state values for metronome configuration
-    let initial_state = state_rx.borrow().clone();
+    let initial_state = state_watch.borrow().clone();
+
+    // Create post-record handler and get controller for ProcessHandler
+    let (mut post_record_handler, post_record_controller) = PostRecordHandler::new()
+        .expect("Could not create post-record handler");
 
     let process_handler = ProcessHandler::new(
         ports, 
         allocator, 
         beep_samples, 
         &initial_state,
+        post_record_controller,
     ).expect("Could not create process handler");
 
     let mut connection_manager = ConnectionManager::new(
-        state_rx,
+        state_watch,
         notification_handler.subscribe(),
         jack_client.name().to_string(),
     )
@@ -82,7 +92,7 @@ async fn main() {
                     break;
                 }
             }
-            result = state_manager.run() => {
+            result = persistence_manager.run() => {
                 if let Err(e) = result {
                     log::error!("StateManager task failed: {}", e);
                 }
@@ -94,6 +104,12 @@ async fn main() {
                 }
                 break;
             }
+            result = post_record_handler.run() => {
+                if let Err(e) = result {
+                    log::error!("PostRecordHandler task failed: {}", e);
+                }
+                break;
+            }
             _ = tokio::signal::ctrl_c() => {
                 log::info!("Stopping");
                 break;

src/connection_manager.rs

@@ -2,7 +2,7 @@ use crate::*;
 use tokio::sync::{broadcast, watch};
 
 pub struct ConnectionManager {
-    state_rx: watch::Receiver<State>,
+    state_watch: watch::Receiver<State>,
     notification_rx: broadcast::Receiver<JackNotification>,
     jack_client: jack::Client,
     jack_client_name: String,
@@ -10,7 +10,7 @@ pub struct ConnectionManager {
 
 impl ConnectionManager {
     pub fn new(
-        state_rx: watch::Receiver<State>,
+        state_watch: watch::Receiver<State>,
         notification_rx: broadcast::Receiver<JackNotification>,
         jack_client_name: String,
     ) -> Result<Self> {
@@ -21,7 +21,7 @@ impl ConnectionManager {
         .map_err(|_| LooperError::JackConnection(std::panic::Location::caller()))?;
 
         Ok(Self {
-            state_rx,
+            state_watch,
             notification_rx,
             jack_client,
             jack_client_name,
@@ -39,7 +39,7 @@ impl ConnectionManager {
     }
 
     async fn restore_connections(&self) {
-        let state = self.state_rx.borrow();
+        let state = self.state_watch.borrow();
 
         for external_port in &state.connections.midi_in {
             let our_port = format!("{}:midi_in", self.jack_client_name);

src/notification_handler.rs

@@ -63,14 +63,7 @@ impl jack::NotificationHandler for NotificationHandler {
             .expect("Could not send port connection notification");
     }
 
-    fn port_registration(&mut self, client: &jack::Client, port_id: jack::PortId, register: bool) {
-        let Some(port_name) = client.port_by_id(port_id) else {
-            return;
-        };
-        let Ok(port_name) = port_name.name() else {
-            return;
-        };
-
+    fn port_registration(&mut self, _client: &jack::Client, _port_id: jack::PortId, register: bool) {
         if register {
             let notification = JackNotification::PortRegistered {};
             self.channel

src/persistence_manager.rs

@@ -2,14 +2,14 @@ use crate::*;
 use std::path::PathBuf;
 use tokio::sync::{broadcast, watch};
 
-pub struct StateManager {
+pub struct PersistenceManager {
     state: State,
     state_tx: watch::Sender<State>,
     notification_rx: broadcast::Receiver<JackNotification>,
     state_file_path: PathBuf,
 }
 
-impl StateManager {
+impl PersistenceManager {
     pub fn new(
         notification_rx: broadcast::Receiver<JackNotification>,
     ) -> (Self, watch::Receiver<State>) {

src/post_record_handler.rs

@@ -0,0 +1,173 @@
+use crate::*;
+use std::path::PathBuf;
+
+/// Request to process a recorded chunk chain
+#[derive(Debug)]
+pub struct PostRecordRequest {
+    pub chunk_chain: Arc<AudioChunk>,
+    pub sample_rate: u32,
+}
+
+/// Response containing the consolidated chunk
+#[derive(Debug)]
+pub struct PostRecordResponse {
+    pub consolidated_chunk: Arc<AudioChunk>,
+}
+
+/// RT-side interface for post-record operations
+#[derive(Debug)]
+pub struct PostRecordController {
+    request_sender: kanal::Sender<PostRecordRequest>,
+    response_receiver: kanal::Receiver<PostRecordResponse>,
+}
+
+impl PostRecordController {
+    /// Send a post-record processing request (RT-safe)
+    pub fn send_request(&self, chunk_chain: Arc<AudioChunk>, sample_rate: u32) -> Result<()> {
+        let request = PostRecordRequest { chunk_chain, sample_rate };
+        
+        match self.request_sender.try_send(request) {
+            Ok(true) => Ok(()),  // Successfully sent
+            Ok(false) => Err(LooperError::ChunkAllocation(std::panic::Location::caller())), // Channel full
+            Err(_) => Err(LooperError::ChunkAllocation(std::panic::Location::caller())), // Channel closed
+        }
+    }
+
+    /// Try to receive a processing response (RT-safe)
+    pub fn try_recv_response(&self) -> Option<PostRecordResponse> {
+        match self.response_receiver.try_recv() {
+            Ok(Some(response)) => Some(response),
+            Ok(None) | Err(_) => None,  // No message or channel closed = None
+        }
+    }
+}
+
+/// Handles post-record processing: consolidation and saving
+pub struct PostRecordHandler {
+    request_receiver: kanal::AsyncReceiver<PostRecordRequest>,
+    response_sender: kanal::AsyncSender<PostRecordResponse>,
+    directory: PathBuf,
+}
+
+impl PostRecordHandler {
+    /// Create new handler and return RT controller
+    pub fn new() -> Result<(Self, PostRecordController)> {
+        // Create channels for bidirectional communication
+        let (request_sender, request_receiver) = kanal::bounded(16);
+        let (response_sender, response_receiver) = kanal::bounded(16);
+
+        let request_receiver = request_receiver.to_async();
+        let response_sender = response_sender.to_async();
+
+        let controller = PostRecordController {
+            request_sender,
+            response_receiver,
+        };
+
+        let handler = Self {
+            request_receiver,
+            response_sender,
+            directory: Self::create_directory()?,
+        };
+
+        Ok((handler, controller))
+    }
+
+    /// Run the async processing task
+    pub async fn run(&mut self) -> Result<()> {
+        while let Ok(request) = self.request_receiver.recv().await {
+            if let Err(e) = self.process_request(request).await {
+                log::error!("Failed to process post-record request: {}", e);
+            }
+        }
+
+        Ok(())
+    }
+
+    /// Process a single post-record request
+    async fn process_request(
+        &self,
+        request: PostRecordRequest,
+    ) -> Result<()> {
+        log::debug!("Processing post-record request for {} samples", 
+                   request.chunk_chain.len());
+
+        // Step 1: Consolidate chunk chain (CPU intensive)
+        let consolidated_chunk = AudioChunk::consolidate(&request.chunk_chain);
+        
+        log::debug!("Consolidated {} samples", consolidated_chunk.sample_count);
+
+        // Step 2: Send consolidated chunk back to RT thread immediately
+        let response = PostRecordResponse {
+            consolidated_chunk: consolidated_chunk.clone(),
+        };
+
+        if let Err(_) = self.response_sender.send(response).await {
+            log::warn!("Failed to send consolidated chunk to RT thread");
+        }
+
+        // Step 3: Save WAV file in background (I/O intensive)
+        let file_path = self.get_file_path();
+
+        match self.save_wav_file(&consolidated_chunk, request.sample_rate, &file_path).await {
+            Ok(_) => log::info!("Saved recording to {:?}", file_path),
+            Err(e) => log::error!("Failed to save recording to {:?}: {}", file_path, e),
+        }
+
+        Ok(())
+    }
+
+    /// Save consolidated chunk as WAV file
+    async fn save_wav_file(
+        &self,
+        chunk: &AudioChunk,
+        sample_rate: u32,
+        file_path: &PathBuf,
+    ) -> Result<()> {
+        // Run WAV writing in blocking task to avoid blocking async runtime
+        let chunk_samples: Vec<f32> = chunk.samples[..chunk.sample_count].to_vec();
+        let file_path_clone = file_path.clone();
+        
+        tokio::task::spawn_blocking(move || {
+            let spec = hound::WavSpec {
+                channels: 1,
+                sample_rate,
+                bits_per_sample: 32,
+                sample_format: hound::SampleFormat::Float,
+            };
+
+            let mut writer = hound::WavWriter::create(&file_path_clone, spec)
+                .map_err(|_| LooperError::StateSave(std::panic::Location::caller()))?;
+
+            // Write all samples from the chunk
+            for sample in chunk_samples {
+                writer.write_sample(sample)
+                    .map_err(|_| LooperError::StateSave(std::panic::Location::caller()))?;
+            }
+
+            writer.finalize()
+                .map_err(|_| LooperError::StateSave(std::panic::Location::caller()))?;
+
+            Ok::<(), LooperError>(())
+        })
+        .await
+        .map_err(|_| LooperError::StateSave(std::panic::Location::caller()))?
+    }
+
+    /// Create save directory and return path  
+    fn create_directory() -> Result<PathBuf> {
+        let mut path = dirs::home_dir()
+            .unwrap_or_else(|| PathBuf::from("."));
+        path.push(".fcb_looper");
+
+        std::fs::create_dir_all(&path)
+            .map_err(|_| LooperError::StateSave(std::panic::Location::caller()))?;
+
+        Ok(path)
+    }
+
+    /// Get file path for track recording
+    fn get_file_path(&self) -> PathBuf {
+        self.directory.join("track.wav")
+    }
+}

src/process_handler.rs

@@ -1,6 +1,4 @@
 use crate::*;
-use crate::metronome::Metronome;
-use crate::track::{TrackTiming, TrackState};
 
 pub struct ProcessHandler<F: ChunkFactory> {
     track: Track,
@@ -8,6 +6,7 @@ pub struct ProcessHandler<F: ChunkFactory> {
     pub ports: JackPorts,
     chunk_factory: F,
     metronome: Metronome,
+    post_record_controller: PostRecordController,
 }
 
 impl<F: ChunkFactory> ProcessHandler<F> {
@@ -16,6 +15,7 @@ impl<F: ChunkFactory> ProcessHandler<F> {
         mut chunk_factory: F, 
         beep_samples: Arc<AudioChunk>, 
         state: &State,
+        post_record_controller: PostRecordController,
     ) -> Result<Self> {
         Ok(Self {
             track: Track::new(&mut chunk_factory)?,
@@ -23,6 +23,7 @@ impl<F: ChunkFactory> ProcessHandler<F> {
             ports,
             chunk_factory,
             metronome: Metronome::new(beep_samples, state),
+            post_record_controller,
         })
     }
 
@@ -66,18 +67,27 @@ impl<F: ChunkFactory> jack::ProcessHandler for ProcessHandler<F> {
         let state_before = self.track.current_state().clone();
         
         // Calculate timing information for track processing
-        let timing = self.calculate_track_timing(beat_sample_index, buffer_size, &state_before);
+        let timing = self.calculate_track_timing(beat_sample_index, &state_before);
         
         // Process track audio with calculated timing
-        if let Err(e) = self.track.process(
+        let should_consolidate = match self.track.process(
             ps, 
             &mut self.ports, 
             timing,
             &mut self.chunk_factory
         ) {
+            Ok(consolidate) => consolidate,
+            Err(e) => {
                 log::error!("Error processing track: {}", e);
                 return jack::Control::Quit;
             }
+        };
+
+        // Handle post-record processing
+        if let Err(e) = self.handle_post_record_processing(should_consolidate, client.sample_rate() as u32) {
+            log::error!("Error handling post-record processing: {}", e);
+            return jack::Control::Quit;
+        }
 
         // Update playback position based on what happened
         self.update_playback_position(beat_sample_index, buffer_size, &state_before);
@@ -87,11 +97,35 @@ impl<F: ChunkFactory> jack::ProcessHandler for ProcessHandler<F> {
 }
 
 impl<F: ChunkFactory> ProcessHandler<F> {
+    /// Handle post-record processing: send requests and swap chunks
+    fn handle_post_record_processing(&mut self, should_consolidate: bool, sample_rate: u32) -> Result<()> {
+        // Send chunk chain for processing if track indicates consolidation needed
+        if should_consolidate {
+            let chunk_chain = self.track.get_audio_chunk();
+            log::debug!("Sending chunk chain with {} samples for post-record processing", 
+                        chunk_chain.len());
+            
+            if let Err(e) = self.post_record_controller.send_request(chunk_chain, sample_rate) {
+                log::warn!("Failed to send post-record request: {}", e);
+            }
+        }
+
+        // Check for consolidation response
+        if let Some(response) = self.post_record_controller.try_recv_response() {
+            log::debug!("Received consolidated chunk with {} samples, swapping in track", 
+                       response.consolidated_chunk.len());
+            
+            // Swap the consolidated chunk into the track
+            self.track.set_audio_chunk(response.consolidated_chunk)?;
+        }
+
+        Ok(())
+    }
+
     /// Calculate timing information for track processing
     fn calculate_track_timing(
         &self,
         beat_sample_index: Option<u32>,
-        buffer_size: usize,
         state_before: &TrackState,
     ) -> TrackTiming {
         match beat_sample_index {

src/track.rs

@@ -21,7 +21,7 @@ pub enum TrackTiming {
 }
 
 pub struct Track {
-    audio_chunks: Option<Arc<AudioChunk>>,
+    audio_chunk: Arc<AudioChunk>,
     length: usize,
     current_state: TrackState,
     next_state: TrackState,
@@ -31,7 +31,7 @@ pub struct Track {
 impl Track {
     pub fn new<F: ChunkFactory>(chunk_factory: &mut F) -> Result<Self> {
         Ok(Self {
-            audio_chunks: None,
+            audio_chunk: chunk_factory.create_chunk()?,
             length: 0,
             current_state: TrackState::Empty,
             next_state: TrackState::Empty,
@@ -40,18 +40,19 @@ impl Track {
     }
 
     /// Main audio processing method called from ProcessHandler
+    /// Returns true if track should be consolidated and saved
     pub fn process<F: ChunkFactory>(
         &mut self,
         ps: &jack::ProcessScope,
         ports: &mut JackPorts,
         timing: TrackTiming,
         chunk_factory: &mut F,
-    ) -> Result<()> {
+    ) -> Result<bool> {
         let input_buffer = ports.audio_in.as_slice(ps);
         let output_buffer = ports.audio_out.as_mut_slice(ps);
         let buffer_size = output_buffer.len();
 
-        match timing {
+        let should_consolidate = match timing {
             TrackTiming::NoBeat { position } => {
                 // No beat in this buffer - process entire buffer with current state
                 self.process_audio_range(
@@ -62,6 +63,7 @@ impl Track {
                     position,
                     chunk_factory,
                 )?;
+                false // No state transition possible without beat
             }
             TrackTiming::Beat { 
                 pre_beat_position, 
@@ -80,8 +82,8 @@ impl Track {
                     )?;
                 }
 
-                // Apply state transition at beat boundary
-                self.apply_state_transition(chunk_factory)?;
+                // Apply state transition at beat boundary and check if consolidation needed
+                let should_consolidate = self.apply_state_transition(chunk_factory)?;
 
                 if beat_sample_index < buffer_size {
                     // Process samples after beat with new current state
@@ -94,10 +96,12 @@ impl Track {
                         chunk_factory,
                     )?;
                 }
-            }
-        }
 
-        Ok(())
+                should_consolidate
+            }
+        };
+
+        Ok(should_consolidate)
     }
 
     /// Process audio for a specific range within the buffer
@@ -142,19 +146,24 @@ impl Track {
     }
 
     /// Apply state transition from next_state to current_state
+    /// Returns true if track should be consolidated and saved
     fn apply_state_transition<F: ChunkFactory>(
         &mut self, 
         chunk_factory: &mut F
-    ) -> Result<()> {
+    ) -> Result<bool> {
+        // Check if this is a Recording → Playing transition (consolidation trigger)
+        let should_consolidate = self.current_state == TrackState::Recording 
+                                 && self.next_state == TrackState::Playing;
+
         // Handle transitions that require setup
         match (&self.current_state, &self.next_state) {
-            (_, TrackState::Recording) => {
+            (current_state, TrackState::Recording) if *current_state != TrackState::Recording => {
                 // Starting to record - clear previous data and create new chunk
                 self.clear_audio_data(chunk_factory)?;
             }
             (_, TrackState::Playing) => {
                 // Starting playback - check if we have audio data
-                if self.audio_chunks.is_none() || self.length == 0 {
+                if self.length == 0 {
                     // No audio data - transition to Idle instead
                     self.next_state = TrackState::Idle;
                 }
@@ -162,7 +171,7 @@ impl Track {
             (_, TrackState::Empty) => {
                 // Clear operation - remove audio data
                 // Note: Actual deallocation will happen later via IO thread
-                self.audio_chunks = None;
+                self.audio_chunk = chunk_factory.create_chunk()?;
                 self.length = 0;
             }
             _ => {
@@ -173,7 +182,7 @@ impl Track {
         // Apply the state transition
         self.current_state = self.next_state.clone();
         
-        Ok(())
+        Ok(should_consolidate)
     }
 
     /// Copy samples from track audio to output buffer with looping
@@ -183,7 +192,6 @@ impl Track {
         sample_count: usize,
         mut playback_position: usize,
     ) -> Result<()> {
-        if let Some(ref audio_chunks) = self.audio_chunks {
         if self.length == 0 {
             output_slice.fill(0.0);
             return Ok(());
@@ -196,8 +204,8 @@ impl Track {
             let samples_until_loop = self.length - playback_position;
             let samples_to_copy = samples_remaining.min(samples_until_loop);
 
-                // Copy directly from audio chunks to output slice
-                audio_chunks.copy_samples(
+            // Copy directly from audio chunk to output slice
+            self.audio_chunk.copy_samples(
                 &mut output_slice[samples_written..samples_written + samples_to_copy],
                 playback_position,
             )?;
@@ -215,10 +223,6 @@ impl Track {
                 playback_position = 0;
             }
         }
-        } else {
-            output_slice.fill(0.0);
-        }
-
         Ok(())
     }
 
@@ -228,15 +232,8 @@ impl Track {
         samples: &[f32],
         chunk_factory: &mut F,
     ) -> Result<()> {
-        if self.audio_chunks.is_none() {
-            self.audio_chunks = Some(chunk_factory.create_chunk()?);
-        }
-
-        if let Some(ref mut chunks) = self.audio_chunks {
-            chunks.append_samples(samples, chunk_factory)?;
+        self.audio_chunk.append_samples(samples, chunk_factory)?;
         self.length += samples.len();
-        }
-
         Ok(())
     }
 
@@ -245,11 +242,25 @@ impl Track {
         &mut self,
         chunk_factory: &mut F,
     ) -> Result<()> {
-        self.audio_chunks = Some(chunk_factory.create_chunk()?);
+        self.audio_chunk = chunk_factory.create_chunk()?;
         self.length = 0;
         Ok(())
     }
 
+    /// Get audio chunk for post-record processing (read-only access)
+    pub fn get_audio_chunk(&self) -> Arc<AudioChunk> {
+        self.audio_chunk.clone()
+    }
+
+    /// Set audio chunk (for swapping in consolidated chunk)
+    pub fn set_audio_chunk(&mut self, chunk: Arc<AudioChunk>) -> Result<()> {
+        if chunk.len() != self.length {
+            return Err(LooperError::OutOfBounds(std::panic::Location::caller()));
+        }
+        self.audio_chunk = chunk;
+        Ok(())
+    }
+
     // Public accessors and commands for MIDI handling
     pub fn current_state(&self) -> &TrackState {
         &self.current_state
@@ -259,10 +270,6 @@ impl Track {
         &self.next_state
     }
 
-    pub fn set_next_state(&mut self, state: TrackState) {
-        self.next_state = state;
-    }
-
     pub fn len(&self) -> usize {
         self.length
     }