Merge pull request 'feat: add sound notification' (#6) from stevanfreeborn/feat/add-sound-notification into main

Cargo.lock

@@ -2120,7 +2120,7 @@ dependencies = [
 
 [[package]]
 name = "termato"
-version = "0.1.0"
+version = "0.1.1"
 dependencies = [
  "cpal",
  "crossterm",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "termato"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2024"
 repository = "https://github.com/StevanFreeborn/termato"
 

README.md

@@ -7,6 +7,8 @@ A minimal and unintrusive Pomodoro timer written in Rust for the terminal.
 - Supports focus sessions and break sessions.
 - System-level alerts to notify you when a session ends.
 - Define custom focus and break session durations from the command line.
+- Cross-platform sound notifications when a session ends.
+- Cross-platform audio visualizer.
 
 ## Keyboard Controls
 
@@ -52,7 +54,7 @@ termato
 
 ### Specifying Options and Custom Session Times
 
-By default, desktop notifications are disabled. You can specify options and custom session durations as command-line arguments:
+By default, desktop notifications, sound alerts, and the visualizer are disabled. You can specify options and custom session durations as command-line arguments:
 
 ```bash
 termato [options] [work_minutes] [break_minutes]
@@ -64,10 +66,19 @@ For example, to enable desktop notifications and run a 50-minute focus session f
 termato -n 50 10
 ```
 
-Or using the long flag:
+To enable both desktop notifications and sound notifications with custom times:
 
 ```bash
-termato --notify 50 10
+termato -ns 50 10
+
+# or with long flags
+termato --notify -sound 50 10
+```
+
+You can also combine short flags together (e.g. -nsz to enable notifications, sound, and the audio visualizer):
+
+```bash
+termato -nsz
 ```
 
 ### Help and Version

src/app.rs

@@ -1,7 +1,8 @@
+use crate::args::CliConfig;
+use crate::constants::SECONDS_PER_MIN;
 use crate::msg::Message;
 use crate::notification::send_desktop_notification;
-
+use crate::sound::play_notification_sound;
-const SECONDS_PER_MIN: u32 = 60;
 
 #[derive(Debug, PartialEq, Eq, Clone, Copy)]
 pub enum TimerMode {
@@ -10,42 +11,31 @@ pub enum TimerMode {
 }
 
 pub struct Termato {
-  pub work_mins: u32,
+  pub config: CliConfig,
-  pub break_mins: u32,
   pub mode: TimerMode,
   pub is_running: bool,
   pub duration_in_secs: u32,
   pub time_remaining_in_sec: u32,
   pub show_help: bool,
-  pub enable_notifications: bool,
+  should_quit: bool,
-  pub enable_visualizer: bool,
-  pub should_quit: bool,
 }
 
 impl Termato {
-  pub fn new(work_mins: u32, break_mins: u32) -> Self {
+  pub fn new(config: CliConfig) -> Self {
+    let duration_in_secs = config.work_mins * SECONDS_PER_MIN;
     Termato {
-      work_mins,
+      config,
-      break_mins,
       mode: TimerMode::Work,
       is_running: false,
-      duration_in_secs: work_mins * SECONDS_PER_MIN,
+      duration_in_secs,
-      time_remaining_in_sec: work_mins * SECONDS_PER_MIN,
+      time_remaining_in_sec: duration_in_secs,
       show_help: false,
-      enable_notifications: false,
-      enable_visualizer: false,
       should_quit: false,
     }
   }
 
-  pub fn with_notifications(mut self, enable: bool) -> Self {
+  pub fn should_quit(&self) -> bool {
-    self.enable_notifications = enable;
+    self.should_quit
-    self
-  }
-
-  pub fn with_visualizer(mut self, enable: bool) -> Self {
-    self.enable_visualizer = enable;
-    self
   }
 
   pub fn update(&mut self, msg: Message) {
@@ -69,8 +59,8 @@ impl Termato {
       TimerMode::Break => TimerMode::Work,
     };
     self.duration_in_secs = match self.mode {
-      TimerMode::Work => self.work_mins * SECONDS_PER_MIN,
+      TimerMode::Work => self.config.work_mins * SECONDS_PER_MIN,
-      TimerMode::Break => self.break_mins * SECONDS_PER_MIN,
+      TimerMode::Break => self.config.break_mins * SECONDS_PER_MIN,
     };
     self.time_remaining_in_sec = self.duration_in_secs;
   }
@@ -80,13 +70,17 @@ impl Termato {
       self.time_remaining_in_sec -= 1;
 
       if self.time_remaining_in_sec == 0 {
-        if self.enable_notifications {
+        if self.config.enable_notifications {
           match self.mode {
             TimerMode::Work => send_desktop_notification("Work Done", "Time to take a break."),
             TimerMode::Break => send_desktop_notification("Break Over", "Time to focus."),
           }
         }
 
+        if self.config.enable_sound {
+          play_notification_sound();
+        }
+
         self.toggle_mode();
       }
     }
@@ -95,7 +89,7 @@ impl Termato {
   pub fn reset(&mut self) {
     self.is_running = false;
     self.mode = TimerMode::Work;
-    self.duration_in_secs = self.work_mins * SECONDS_PER_MIN;
+    self.duration_in_secs = self.config.work_mins * SECONDS_PER_MIN;
     self.time_remaining_in_sec = self.duration_in_secs;
   }
 
@@ -108,25 +102,35 @@ impl Termato {
 mod tests {
   use super::*;
 
+  fn get_test_config(work_mins: u32, break_mins: u32) -> CliConfig {
+    CliConfig {
+      work_mins,
+      break_mins,
+      enable_notifications: false,
+      enable_sound: false,
+      enable_visualizer: false,
+    }
+  }
+
   #[test]
   fn termato_new_when_called_it_should_return_expected_starting_state() {
-    let result = Termato::new(25, 5);
+    let result = Termato::new(get_test_config(25, 5));
 
-    assert_eq!(result.work_mins, 25);
+    assert_eq!(result.config.work_mins, 25);
-    assert_eq!(result.break_mins, 5);
+    assert_eq!(result.config.break_mins, 5);
     assert_eq!(result.mode, TimerMode::Work);
     assert!(!result.is_running);
     assert_eq!(result.duration_in_secs, 1500);
     assert_eq!(result.time_remaining_in_sec, 1500);
     assert!(!result.show_help);
-    assert!(!result.enable_notifications);
+    assert!(!result.config.enable_notifications);
-    assert!(!result.enable_visualizer);
+    assert!(!result.config.enable_sound);
     assert!(!result.should_quit);
   }
 
   #[test]
   fn termato_update_when_called_with_messages_it_should_update_state() {
-    let mut termato = Termato::new(25, 5);
+    let mut termato = Termato::new(get_test_config(25, 5));
 
     termato.update(Message::ToggleRunning);
     assert!(termato.is_running);
@@ -147,7 +151,7 @@ mod tests {
 
   #[test]
   fn termato_tick_when_called_and_not_running_it_should_do_nothing() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
 
     termato.update(Message::Tick);
 
@@ -156,7 +160,7 @@ mod tests {
 
   #[test]
   fn termato_tick_when_called_and_no_time_remaining_it_should_do_nothing() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
     termato.is_running = true;
     termato.time_remaining_in_sec = 0;
 
@@ -167,7 +171,7 @@ mod tests {
 
   #[test]
   fn termato_tick_when_running_and_time_reamining_it_should_reduce_remaining_by_one() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
     termato.is_running = true;
 
     termato.update(Message::Tick);
@@ -177,7 +181,7 @@ mod tests {
 
   #[test]
   fn termato_tick_when_running_on_work_and_time_remaining_reaches_zero_it_should_toggle_to_break() {
-    let mut termato = Termato::new(1, 2);
+    let mut termato = Termato::new(get_test_config(1, 2));
     termato.is_running = true;
     termato.time_remaining_in_sec = 1;
 
@@ -190,7 +194,7 @@ mod tests {
 
   #[test]
   fn termato_tick_when_running_on_break_and_time_remaining_reaches_zero_it_should_toggle_to_work() {
-    let mut termato = Termato::new(2, 1);
+    let mut termato = Termato::new(get_test_config(2, 1));
     termato.mode = TimerMode::Break;
     termato.is_running = true;
     termato.time_remaining_in_sec = 1;
@@ -204,7 +208,7 @@ mod tests {
 
   #[test]
   fn termato_toggle_mode_when_called_it_should_toggle_the_mode() {
-    let mut termato = Termato::new(2, 1);
+    let mut termato = Termato::new(get_test_config(2, 1));
 
     termato.toggle_mode();
     assert_eq!(termato.mode, TimerMode::Break);
@@ -219,7 +223,7 @@ mod tests {
 
   #[test]
   fn termato_toggle_running_when_called_and_already_running_it_should_pause() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
     termato.is_running = true;
 
     termato.toggle_running();
@@ -229,7 +233,7 @@ mod tests {
 
   #[test]
   fn termato_toggle_running_when_called_and_already_paused_it_should_run() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
 
     termato.toggle_running();
 
@@ -238,7 +242,7 @@ mod tests {
 
   #[test]
   fn termato_rest_when_called_it_should_reset_the_apps_state() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
     termato.is_running = true;
     termato.mode = TimerMode::Break;
     termato.duration_in_secs = 1;
@@ -254,7 +258,7 @@ mod tests {
 
   #[test]
   fn termato_toggle_help_when_called_it_should_toggle_help() {
-    let mut termato = Termato::new(1, 1);
+    let mut termato = Termato::new(get_test_config(1, 1));
 
     termato.toggle_help();
 
@@ -264,22 +268,4 @@ mod tests {
 
     assert!(!termato.show_help);
   }
-
-  #[test]
-  fn termato_notifications_when_called_it_should_verify_opt_in_behavior() {
-    let result = Termato::new(25, 5);
-    assert!(!result.enable_notifications);
-
-    let result = result.with_notifications(true);
-    assert!(result.enable_notifications);
-  }
-
-  #[test]
-  fn termato_visualizer_when_called_it_should_verify_opt_in_behavior() {
-    let result = Termato::new(25, 5);
-    assert!(!result.enable_visualizer);
-
-    let result = result.with_visualizer(true);
-    assert!(result.enable_visualizer);
-  }
 }

src/args.rs

@@ -0,0 +1,259 @@
+use std::env;
+
+use crate::constants::{DEFAULT_BREAK_MINS, DEFAULT_WORK_MINS};
+
+pub const FLAG_HELP: &str = "-h";
+pub const FLAG_HELP_LONG: &str = "--help";
+pub const FLAG_VERSION: &str = "-v";
+pub const FLAG_VERSION_LONG: &str = "--version";
+pub const FLAG_NOTIFY: &str = "-n";
+pub const FLAG_NOTIFY_LONG: &str = "--notify";
+pub const FLAG_SOUND: &str = "-s";
+pub const FLAG_SOUND_LONG: &str = "--sound";
+pub const FLAG_VISUALIZER: &str = "-z";
+pub const FLAG_VISUALIZER_LONG: &str = "--visualizer";
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct CliConfig {
+  pub work_mins: u32,
+  pub break_mins: u32,
+  pub enable_notifications: bool,
+  pub enable_sound: bool,
+  pub enable_visualizer: bool,
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub enum CliAction {
+  Run(CliConfig),
+  PrintHelp,
+  PrintVersion,
+  Error(String),
+}
+
+pub struct Cli;
+
+impl Cli {
+  pub fn parse() -> CliAction {
+    Self::parse_args(env::args().collect())
+  }
+
+  pub fn parse_args(args: Vec<String>) -> CliAction {
+    let mut enable_notifications = false;
+    let mut enable_visualizer = false;
+    let mut enable_sound = false;
+    let mut positional = Vec::new();
+
+    for arg in args.into_iter().skip(1) {
+      match arg.as_str() {
+        FLAG_HELP | FLAG_HELP_LONG => return CliAction::PrintHelp,
+        FLAG_VERSION | FLAG_VERSION_LONG => return CliAction::PrintVersion,
+        FLAG_SOUND | FLAG_SOUND_LONG => enable_sound = true,
+        FLAG_VISUALIZER | FLAG_VISUALIZER_LONG => enable_visualizer = true,
+        "--" => {}
+        s if s.starts_with("--") => match s {
+          FLAG_NOTIFY_LONG => enable_notifications = true,
+          FLAG_VISUALIZER_LONG => enable_visualizer = true,
+          FLAG_SOUND_LONG => enable_sound = true,
+          _ => return CliAction::Error(format!("Unknown option: '{}'", s)),
+        },
+        s if s.starts_with('-') => {
+          for ch in s.chars().skip(1) {
+            match ch {
+              'h' => return CliAction::PrintHelp,
+              'v' => return CliAction::PrintVersion,
+              'n' => enable_notifications = true,
+              's' => enable_sound = true,
+              'z' => enable_visualizer = true,
+              _ => return CliAction::Error(format!("Unknown option: '-{}'", ch)),
+            }
+          }
+        }
+        s => positional.push(s.to_string()),
+      }
+    }
+
+    let numbers: Vec<u32> = positional
+      .iter()
+      .filter_map(|s| s.parse::<u32>().ok())
+      .collect();
+
+    let work_mins = numbers.first().copied().unwrap_or(DEFAULT_WORK_MINS);
+    let break_mins = numbers.get(1).copied().unwrap_or(DEFAULT_BREAK_MINS);
+
+    if numbers.len() > 2 {
+      return CliAction::Error(format!("Unexpected argument: '{}'", positional[2]));
+    }
+
+    CliAction::Run(CliConfig {
+      work_mins,
+      break_mins,
+      enable_notifications,
+      enable_sound,
+      enable_visualizer,
+    })
+  }
+
+  pub fn print_help() {
+    println!("Usage: termato [options] [work_minutes] [break_minutes]");
+
+    println!();
+
+    println!("Options:");
+
+    println!(
+      "  {:<19} Enable desktop notifications",
+      format!("{}, {}", FLAG_NOTIFY, FLAG_NOTIFY_LONG)
+    );
+
+    println!(
+      "  {:<19} Enable sound notifications",
+      format!("{}, {}", FLAG_SOUND, FLAG_SOUND_LONG)
+    );
+
+    println!(
+      "  {:<19} Display visualizer of playing audio",
+      format!("{}, {}", FLAG_VISUALIZER, FLAG_VISUALIZER_LONG)
+    );
+
+    println!(
+      "  {:<19} Print this help message",
+      format!("{}, {}", FLAG_HELP, FLAG_HELP_LONG)
+    );
+
+    println!(
+      "  {:<19} Print the version number",
+      format!("{}, {}", FLAG_VERSION, FLAG_VERSION_LONG)
+    );
+
+    println!();
+
+    println!(
+      "Defaults: work_minutes = {}, break_minutes = {}",
+      DEFAULT_WORK_MINS, DEFAULT_BREAK_MINS
+    );
+  }
+
+  pub fn print_version() {
+    println!("termato version {}", env!("CARGO_PKG_VERSION"));
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_defaults() {
+    let args = vec!["termato".to_string()];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Run(CliConfig {
+        work_mins: 25,
+        break_mins: 5,
+        enable_notifications: false,
+        enable_sound: false,
+        enable_visualizer: false,
+      })
+    );
+  }
+
+  #[test]
+  fn test_cargo_run_syntax_with_dot_and_dash_dash() {
+    let args = vec![
+      "target/debug/termato.exe".to_string(),
+      ".".to_string(),
+      "--".to_string(),
+      "-z".to_string(),
+    ];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Run(CliConfig {
+        work_mins: 25,
+        break_mins: 5,
+        enable_notifications: false,
+        enable_sound: false,
+        enable_visualizer: true,
+      })
+    );
+  }
+
+  #[test]
+  fn test_custom_time_and_flags() {
+    let args = vec![
+      "termato".to_string(),
+      "-n".to_string(),
+      "-z".to_string(),
+      "50".to_string(),
+      "10".to_string(),
+    ];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Run(CliConfig {
+        work_mins: 50,
+        break_mins: 10,
+        enable_notifications: true,
+        enable_sound: false,
+        enable_visualizer: true,
+      })
+    );
+  }
+
+  #[test]
+  fn test_help_flag() {
+    let args = vec!["termato".to_string(), "--help".to_string()];
+    assert_eq!(Cli::parse_args(args), CliAction::PrintHelp);
+  }
+
+  #[test]
+  fn test_unknown_flag() {
+    let args = vec!["termato".to_string(), "--foo".to_string()];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Error("Unknown option: '--foo'".to_string())
+    );
+  }
+
+  #[test]
+  fn test_non_numeric_positional_defaults() {
+    let args = vec!["termato".to_string(), "abc".to_string()];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Run(CliConfig {
+        work_mins: 25,
+        break_mins: 5,
+        enable_notifications: false,
+        enable_sound: false,
+        enable_visualizer: false,
+      })
+    );
+  }
+
+  #[test]
+  fn test_combined_short_flags() {
+    let args = vec![
+      "termato".to_string(),
+      "-nsz".to_string(),
+      "25".to_string(),
+      "5".to_string(),
+    ];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Run(CliConfig {
+        work_mins: 25,
+        break_mins: 5,
+        enable_notifications: true,
+        enable_sound: true,
+        enable_visualizer: true,
+      })
+    );
+  }
+
+  #[test]
+  fn test_combined_short_flags_with_invalid_char() {
+    let args = vec!["termato".to_string(), "-nxz".to_string()];
+    assert_eq!(
+      Cli::parse_args(args),
+      CliAction::Error("Unknown option: '-x'".to_string())
+    );
+  }
+}

src/audio.rs

@@ -248,14 +248,28 @@ impl AudioVisualizer {
       thread::sleep(std::time::Duration::from_millis(16));
 
       let samples = {
-        let buf = match audio_buffer.lock() {
+        let mut buf = match audio_buffer.lock() {
           Ok(b) => b,
           Err(_) => continue,
         };
+
+        // decay heights smoothly
         if buf.len() < chunk_size {
+          for val in prev_heights.iter_mut() {
+            *val = (*val - falloff).max(0.0);
+          }
+
+          if let Ok(mut bars) = bar_data.lock() {
+            for (i, val) in prev_heights.iter().enumerate() {
+              bars[i] = ((*val * 10.0).clamp(0.0, 100.0)) as u64;
+            }
+          }
+
           continue;
         }
-        buf[buf.len() - chunk_size..].to_vec()
+
+        // drain the consumed samples
+        buf.drain(0..chunk_size).collect::<Vec<f32>>()
       };
 
       Self::apply_hann_window(&samples, &mut windowed_buffer);

src/constants.rs

@@ -0,0 +1,4 @@
+pub const SECONDS_PER_MIN: u32 = 60;
+pub const DEFAULT_WORK_MINS: u32 = 25;
+pub const DEFAULT_BREAK_MINS: u32 = 5;
+pub const VIZ_NUM_BARS: u16 = 64;

src/events.rs

@@ -1,5 +1,5 @@
-use crossterm::event::{self, Event, KeyCode, KeyModifiers};
 use crate::msg::Message;
+use crossterm::event::{self, Event, KeyCode, KeyModifiers};
 
 pub fn handle_event(event: Event) -> Option<Message> {
   if let Event::Key(key) = event

src/main.rs

@@ -1,8 +1,11 @@
 mod app;
+mod args;
 mod audio;
+mod constants;
 mod events;
 mod msg;
 mod notification;
+mod sound;
 mod terminal;
 mod ui;
 
@@ -24,26 +27,27 @@ use msg::Message;
 use terminal::TerminalGuard;
 use ui::render_app;
 
+use args::{Cli, CliAction};
+
+use crate::constants::VIZ_NUM_BARS;
+
 fn main() -> Result<(), io::Error> {
-  let args: Vec<String> = std::env::args().collect();
+  let config = match Cli::parse() {
-
+    CliAction::PrintHelp => {
-  if args.iter().any(|arg| arg == "-h" || arg == "--help") {
+      Cli::print_help();
-    println!("Usage: termato [options] [work_minutes] [break_minutes]");
+      return Ok(());
-    println!();
+    }
-    println!("Options:");
+    CliAction::PrintVersion => {
-    println!("  -n, --notify      Enable desktop notifications");
+      Cli::print_version();
-    println!("  -h, --help        Print this help message");
+      return Ok(());
-    println!("  -v, --version     Print the version number");
+    }
-    println!("  -z, --visualizer  Display visualizer of playing audio");
+    CliAction::Error(err) => {
-    println!();
+      eprintln!("Error: {}", err);
-    println!("Defaults: work_minutes = 25, break_minutes = 5");
+      eprintln!("Run 'termato --help' for usage instructions.");
-    return Ok(());
+      std::process::exit(1);
-  }
+    }
-
+    CliAction::Run(cfg) => cfg,
-  if args.iter().any(|arg| arg == "-v" || arg == "--version") {
+  };
-    println!("termato version {}", env!("CARGO_PKG_VERSION"));
-    return Ok(());
-  }
 
   let _guard = TerminalGuard::new()?;
 
@@ -51,41 +55,13 @@ fn main() -> Result<(), io::Error> {
   let mut terminal = Terminal::new(backend)?;
   let font = Toilet::smblock().unwrap();
 
-  let enable_visualizer = args.iter().any(|arg| arg == "-z" || arg == "--visualizer");
+  let visualizer = if config.enable_visualizer {
-  let enable_notifications = args.iter().any(|arg| arg == "-n" || arg == "--notify");
+    Some(AudioVisualizer::new(VIZ_NUM_BARS as usize))
-
-  let visualizer = if enable_visualizer {
-    Some(AudioVisualizer::new(64))
   } else {
     None
   };
 
-  let is_flag = |arg: &str| {
+  let mut termato = Termato::new(config);
-    arg == "-n"
-      || arg == "--notify"
-      || arg == "-z"
-      || arg == "--visualizer"
-      || arg == "-h"
-      || arg == "--help"
-      || arg == "-v"
-      || arg == "--version"
-  };
-
-  let positional_args: Vec<&String> = args.iter().skip(1).filter(|arg| !is_flag(arg)).collect();
-
-  let work_mins = positional_args
-    .first()
-    .and_then(|s| s.parse().ok())
-    .unwrap_or(25);
-
-  let break_mins = positional_args
-    .get(1)
-    .and_then(|s| s.parse().ok())
-    .unwrap_or(5);
-
-  let mut termato = Termato::new(work_mins, break_mins)
-    .with_notifications(enable_notifications)
-    .with_visualizer(enable_visualizer);
 
   let (tx, rx) = mpsc::channel();
 
@@ -98,7 +74,7 @@ fn main() -> Result<(), io::Error> {
     }
   });
 
-  while !termato.should_quit {
+  while !termato.should_quit() {
     terminal.draw(|f| render_app(&termato, f, &font, visualizer.as_ref()))?;
 
     if event::poll(Duration::from_millis(16))? {

src/sound.rs

@@ -0,0 +1,96 @@
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{LazyLock, mpsc};
+
+use std::time::Duration;
+
+use cpal::traits::{DeviceTrait, HostTrait, StreamTrait};
+
+const FREQ_D5_HZ: f32 = 587.33;
+const FREQ_A5_HZ: f32 = 880.00;
+
+const NOTE_1_DURATION_SECS: f32 = 0.15;
+const NOTE_2_DURATION_SECS: f32 = 0.25;
+const TOTAL_CHIME_DURATION_SECS: f32 = NOTE_1_DURATION_SECS + NOTE_2_DURATION_SECS;
+const CHIME_VOLUME_GAIN: f32 = 0.25;
+
+static SOUND_BUSY: LazyLock<AtomicBool> = LazyLock::new(|| AtomicBool::new(false));
+
+pub fn play_notification_sound() {
+  if SOUND_BUSY.swap(true, Ordering::AcqRel) {
+    return;
+  }
+
+  std::thread::spawn(move || {
+    // term bell fall back
+    print!("\x07");
+
+    let _ = std::io::Write::flush(&mut std::io::stdout());
+    let _ = play_audio_chime();
+
+    SOUND_BUSY.store(false, Ordering::Release);
+  });
+}
+
+fn synthesize_sine_wave(freq_hz: f32, t_seconds: f32) -> f32 {
+  (2.0 * std::f32::consts::PI * freq_hz * t_seconds).sin()
+}
+
+fn calculate_linear_decay(t_seconds: f32, duration_secs: f32) -> f32 {
+  (1.0 - (t_seconds / duration_secs)).max(0.0)
+}
+
+fn play_audio_chime() -> Result<(), Box<dyn std::error::Error>> {
+  let host = cpal::default_host();
+
+  let device = host
+    .default_output_device()
+    .ok_or("No default output audio device found")?;
+
+  let config: cpal::StreamConfig = device.default_output_config()?.into();
+
+  let sample_rate = config.sample_rate as f32;
+  let channels = config.channels as usize;
+
+  let mut sample_clock = 0u64;
+  let (tx, rx) = mpsc::channel::<()>();
+
+  let stream = device.build_output_stream(
+    config,
+    move |data: &mut [f32], _| {
+      for frame in data.chunks_mut(channels) {
+        // Convert sample counter to elapsed time in seconds
+        let elapsed_time = sample_clock as f32 / sample_rate;
+        sample_clock += 1;
+
+        let sample = if elapsed_time < NOTE_1_DURATION_SECS {
+          let wave = synthesize_sine_wave(FREQ_D5_HZ, elapsed_time);
+          let envelope = calculate_linear_decay(elapsed_time, NOTE_1_DURATION_SECS);
+          wave * envelope * CHIME_VOLUME_GAIN
+        } else if elapsed_time < TOTAL_CHIME_DURATION_SECS {
+          let t_note2 = elapsed_time - NOTE_1_DURATION_SECS;
+          let wave = synthesize_sine_wave(FREQ_A5_HZ, t_note2);
+          let envelope = calculate_linear_decay(t_note2, NOTE_2_DURATION_SECS);
+          wave * envelope * CHIME_VOLUME_GAIN
+        } else {
+          0.0
+        };
+
+        for channel in frame.iter_mut() {
+          *channel = sample;
+        }
+
+        if elapsed_time >= TOTAL_CHIME_DURATION_SECS {
+          let _ = tx.send(());
+        }
+      }
+    },
+    |err| eprintln!("Audio output stream error: {}", err),
+    None,
+  )?;
+
+  stream.play()?;
+
+  let _ = rx.recv_timeout(Duration::from_millis(500));
+
+  Ok(())
+}

src/ui.rs

@@ -6,8 +6,11 @@ use ratatui::{
   widgets::{Block, Borders, Clear, Paragraph},
 };
 
-use crate::app::{Termato, TimerMode};
+use crate::{
-use crate::audio::AudioVisualizer;
+  app::{Termato, TimerMode},
+  constants::SECONDS_PER_MIN,
+};
+use crate::{audio::AudioVisualizer, constants::VIZ_NUM_BARS};
 
 // use unicode blocks for rendering
 // Empty        -> " "
@@ -52,8 +55,8 @@ pub fn render_app(
 ) {
   let size = f.area();
 
-  let minutes = app.time_remaining_in_sec / 60;
+  let minutes = app.time_remaining_in_sec / SECONDS_PER_MIN;
-  let seconds = app.time_remaining_in_sec % 60;
+  let seconds = app.time_remaining_in_sec % SECONDS_PER_MIN;
   let time_str = format!("{:02}:{:02}", minutes, seconds);
 
   let time_color = if !app.is_running {
@@ -76,7 +79,7 @@ pub fn render_app(
   let text_height = text_lines.len() as u16;
 
   let viz_height = if visualizer.is_some() { 1 } else { 0 };
-  let viz_width = 64;
+  let viz_width = VIZ_NUM_BARS;
 
   let content_height = text_height + viz_height;