feat: add build script for cross-platform executables and update version to 0.3.0

* improved splash screen
* improved menu
* added signed mode (two's complement) for all game modes

.gitignore

@@ -1,3 +1,4 @@
 /target
 /binbreak_highscores.txt
 /.idea
+/executables

Cargo.lock

@@ -40,7 +40,7 @@ dependencies = [
 
 [[package]]
 name = "binbreak"
-version = "0.1.0"
+version = "0.3.0"
 dependencies = [
  "color-eyre",
  "crossterm 0.29.0",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "binbreak"
-version = "0.1.0"
+version = "0.3.0"
 description = "A terminal based binary number guessing game"
 authors = ["William Raendchen <william@holonaut.io>"]
 license = "MIT"

README.md

@@ -37,6 +37,7 @@ There is one file for linux and one for windows (.exe).
 
 ## Controls
 - use the arrow or vim keys for navigation
+- use left/right to toggle signed/unsigned mode
 - press Enter to confirm choices
 - press Esc or Q to exit a game mode or the game. CTRL+C also works to exit the game.
 

build.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+
+# Build script for binbreak game
+# Builds for Linux and Windows, copies executables to executables/ directory
+
+set -e  # Exit on error
+
+echo "🔨 Building binbreak for multiple platforms..."
+echo ""
+
+# Create executables directory if it doesn't exist
+EXEC_DIR="executables"
+mkdir -p "$EXEC_DIR"
+
+# Get version from Cargo.toml
+VERSION=$(grep '^version' Cargo.toml | head -n1 | cut -d'"' -f2)
+
+# Build for Linux (native)
+echo "📦 Building for Linux (x86_64)..."
+cargo build --release
+LINUX_BIN="binbreak-v${VERSION}-linux-x86_64"
+cp "target/release/binbreak" "$EXEC_DIR/$LINUX_BIN"
+echo "✅ Linux build complete: $EXEC_DIR/$LINUX_BIN"
+echo ""
+
+# Build for Windows
+echo "📦 Building for Windows (x86_64)..."
+if ! rustup target list | grep -q "x86_64-pc-windows-gnu (installed)"; then
+    echo "⚠️  Installing Windows target (x86_64-pc-windows-gnu)..."
+    rustup target add x86_64-pc-windows-gnu
+fi
+
+cargo build --release --target x86_64-pc-windows-gnu
+WINDOWS_BIN="binbreak-v${VERSION}-windows-x86_64.exe"
+cp "target/x86_64-pc-windows-gnu/release/binbreak.exe" "$EXEC_DIR/$WINDOWS_BIN"
+echo "✅ Windows build complete: $EXEC_DIR/$WINDOWS_BIN"
+echo ""
+
+# Print summary
+echo "🎉 All builds complete!"
+echo ""
+echo "Executables:"
+ls -lh "$EXEC_DIR" | tail -n +2
+echo ""
+echo "Location: $EXEC_DIR/"
+

src/app.rs

@@ -1,28 +1,61 @@
 use crate::binary_numbers::{BinaryNumbersGame, Bits};
 use crate::keybinds;
 use crate::main_screen_widget::MainScreenWidget;
-use crate::utils::{AsciiArtWidget, AsciiCells};
+use crate::utils::ProceduralAnimationWidget;
 use crossterm::event;
 use crossterm::event::{Event, KeyCode, KeyEvent, KeyEventKind, KeyModifiers};
 use indoc::indoc;
 use ratatui::buffer::Buffer;
 use ratatui::layout::Rect;
-use ratatui::prelude::{Color, Modifier, Span, Style, Widget};
+use ratatui::prelude::{Color, Modifier, Span, Style};
 use ratatui::widgets::{List, ListItem, ListState};
 use std::cmp;
-use std::collections::HashMap;
-use std::sync::atomic::{AtomicUsize, Ordering};
 use std::thread;
-use std::time::Instant;
+use std::time::{Duration, Instant};
 
-static LAST_SELECTED_INDEX: AtomicUsize = AtomicUsize::new(4);
-
-fn get_last_selected_index() -> usize {
-    LAST_SELECTED_INDEX.load(Ordering::Relaxed)
+#[derive(Copy, Clone, PartialEq, Debug)]
+pub enum NumberMode {
+    Unsigned,
+    Signed,
 }
 
-fn set_last_selected_index(index: usize) {
-    LAST_SELECTED_INDEX.store(index, Ordering::Relaxed);
+impl NumberMode {
+    pub const fn label(&self) -> &'static str {
+        match self {
+            Self::Unsigned => "UNSIGNED",
+            Self::Signed => "SIGNED",
+        }
+    }
+}
+
+/// Persistent application preferences that survive across menu/game transitions
+#[derive(Copy, Clone, Debug)]
+struct AppPreferences {
+    last_selected_index: usize,
+    last_number_mode: NumberMode,
+}
+
+impl Default for AppPreferences {
+    fn default() -> Self {
+        Self {
+            last_selected_index: 4, // Default to "byte 8 bit"
+            last_number_mode: NumberMode::Unsigned,
+        }
+    }
+}
+
+/// Get the color associated with a specific difficulty level / game mode
+pub fn get_mode_color(bits: &Bits) -> Color {
+    // Color scheme: progression from easy (green/cyan) to hard (yellow/red)
+    match bits {
+        Bits::Four => Color::Rgb(100, 255, 100),        // green
+        Bits::FourShift4 => Color::Rgb(100, 255, 180),  // cyan
+        Bits::FourShift8 => Color::Rgb(100, 220, 255),  // light blue
+        Bits::FourShift12 => Color::Rgb(100, 180, 255), // blue
+        Bits::Eight => Color::Rgb(150, 120, 255),       // royal blue
+        Bits::Twelve => Color::Rgb(200, 100, 255),      // purple
+        Bits::Sixteen => Color::Rgb(255, 80, 150),      // pink
+    }
 }
 
 #[derive(Copy, Clone, PartialEq, Debug)]
@@ -32,40 +65,54 @@ enum FpsMode {
 }
 
 enum AppState {
-    Start(StartMenuState),
-    Playing(BinaryNumbersGame),
+    Start(StartMenuState, AppPreferences),
+    Playing(BinaryNumbersGame, AppPreferences),
     Exit,
 }
 
-fn handle_start_input(state: &mut StartMenuState, key: KeyEvent) -> Option<AppState> {
+fn handle_start_input(
+    state: &mut StartMenuState,
+    key: KeyEvent,
+    prefs: AppPreferences,
+) -> Option<(AppState, AppPreferences)> {
     match key {
         x if keybinds::is_up(x) => state.select_previous(),
         x if keybinds::is_down(x) => state.select_next(),
+        x if keybinds::is_left(x) | keybinds::is_right(x) => state.toggle_number_mode(),
         x if keybinds::is_select(x) => {
             let bits = state.selected_bits();
-            // Store the current selection before entering the game
-            set_last_selected_index(state.selected_index());
-            return Some(AppState::Playing(BinaryNumbersGame::new(bits)));
+            let number_mode = state.number_mode;
+            // Update preferences with current selection
+            let updated_prefs = AppPreferences {
+                last_selected_index: state.selected_index(),
+                last_number_mode: state.number_mode,
+            };
+            return Some((
+                AppState::Playing(BinaryNumbersGame::new(bits, number_mode), updated_prefs),
+                updated_prefs,
+            ));
         },
-        x if keybinds::is_exit(x) => return Some(AppState::Exit),
+        x if keybinds::is_exit(x) => return Some((AppState::Exit, prefs)),
+        KeyEvent { code: KeyCode::Char('a' | 'A'), .. } => state.toggle_animation(),
         _ => {},
     }
     None
 }
 
 fn render_start_screen(state: &mut StartMenuState, area: Rect, buf: &mut Buffer) {
-    // Build ASCII art to obtain real dimensions
-    let cells = ascii_art_cells();
-    let ascii_width = cells.get_width();
-    let ascii_height = cells.get_height();
-    let ascii_widget = AsciiArtWidget::new(cells);
+    // Get animation dimensions
+    let ascii_width = state.animation.get_width();
+    let ascii_height = state.animation.get_height();
 
     let selected = state.selected_index();
     let upper_labels: Vec<String> = state.items.iter().map(|(l, _)| l.to_uppercase()).collect();
     #[allow(clippy::cast_possible_truncation)]
     let max_len = upper_labels.iter().map(|s| s.len() as u16).max().unwrap_or(0);
 
-    let list_width = 2 + max_len; // marker + space + label
+    // Calculate width for both columns: marker + space + label + spacing + mode
+    let mode_label_width = 8; // "UNSIGNED" or "SIGNED  " (8 chars for alignment)
+    let column_spacing = 4; // spaces between difficulty and mode columns
+    let list_width = 2 + max_len + column_spacing + mode_label_width; // marker + space + label + spacing + mode
     #[allow(clippy::cast_possible_truncation)]
     let list_height = upper_labels.len() as u16;
 
@@ -90,28 +137,40 @@ fn render_start_screen(state: &mut StartMenuState, area: Rect, buf: &mut Buffer)
         list_height.min(area.height.saturating_sub(list_y - area.y)),
     );
 
-    // Render ASCII art
-    ascii_widget.render(ascii_area, buf);
+    // Get color for the selected menu item
+    let selected_color = get_mode_color(&state.items[selected].1);
 
-    // Palette for menu flair
-    let palette = [
-        Color::LightGreen,
-        Color::LightCyan,
-        Color::LightBlue,
-        Color::LightMagenta,
-        Color::LightYellow,
-        Color::LightRed,
-    ];
+    // Update animation color to match selected menu item
+    state.animation.set_highlight_color(selected_color);
+
+    // Render ASCII animation (handles paused state internally)
+    state.animation.render_to_buffer(ascii_area, buf);
 
     let items: Vec<ListItem> = upper_labels
         .into_iter()
         .enumerate()
         .map(|(i, label)| {
-            let marker = if i == selected { '»' } else { ' ' };
-            let padded = format!("{:<width$}", label, width = max_len as usize);
-            let line = format!("{marker} {padded}");
-            let style =
-                Style::default().fg(palette[i % palette.len()]).add_modifier(Modifier::BOLD);
+            let is_selected = i == selected;
+            let marker = if is_selected { '»' } else { ' ' };
+            let padded_label = format!("{:<width$}", label, width = max_len as usize);
+
+            // Add number mode for selected item
+            let mode_display = if is_selected {
+                format!("{:>width$}", state.number_mode.label(), width = mode_label_width as usize)
+            } else {
+                " ".repeat(mode_label_width as usize)
+            };
+
+            let line = format!("{marker} {padded_label}    {mode_display}");
+
+            let item_color = get_mode_color(&state.items[i].1);
+            let mut style = Style::default().fg(item_color).add_modifier(Modifier::BOLD);
+
+            // Make selected item extra prominent with background highlight
+            if is_selected {
+                style = style.bg(Color::Rgb(40, 40, 40));
+            }
+
             ListItem::new(Span::styled(line, style))
         })
         .collect();
@@ -133,12 +192,16 @@ fn handle_crossterm_events(app_state: &mut AppState) -> color_eyre::Result<()> {
             // state-specific input handling
             _ => {
                 *app_state = match std::mem::replace(app_state, AppState::Exit) {
-                    AppState::Start(mut menu) => {
-                        handle_start_input(&mut menu, key).unwrap_or(AppState::Start(menu))
+                    AppState::Start(mut menu, prefs) => {
+                        if let Some((new_state, _)) = handle_start_input(&mut menu, key, prefs) {
+                            new_state
+                        } else {
+                            AppState::Start(menu, prefs)
+                        }
                     },
-                    AppState::Playing(mut game) => {
+                    AppState::Playing(mut game, prefs) => {
                         game.handle_input(key);
-                        AppState::Playing(game)
+                        AppState::Playing(game, prefs)
                     },
                     AppState::Exit => AppState::Exit,
                 }
@@ -158,7 +221,8 @@ fn get_fps_mode(game: &BinaryNumbersGame) -> FpsMode {
 }
 
 pub fn run_app(terminal: &mut ratatui::DefaultTerminal) -> color_eyre::Result<()> {
-    let mut app_state = AppState::Start(StartMenuState::new());
+    let prefs = AppPreferences::default();
+    let mut app_state = AppState::Start(StartMenuState::new(prefs), prefs);
     let mut last_frame_time = Instant::now();
     let target_frame_duration = std::time::Duration::from_millis(33); // ~30 FPS
 
@@ -168,22 +232,22 @@ pub fn run_app(terminal: &mut ratatui::DefaultTerminal) -> color_eyre::Result<()
         last_frame_time = now;
 
         // Advance game BEFORE drawing so stats are updated
-        if let AppState::Playing(game) = &mut app_state {
+        if let AppState::Playing(game, prefs) = &mut app_state {
             game.run(dt.as_secs_f64());
             if game.is_exit_intended() {
-                app_state = AppState::Start(StartMenuState::new());
+                app_state = AppState::Start(StartMenuState::new(*prefs), *prefs);
                 continue;
             }
         }
 
         terminal.draw(|f| match &mut app_state {
-            AppState::Start(menu) => render_start_screen(menu, f.area(), f.buffer_mut()),
-            AppState::Playing(game) => f.render_widget(&mut *game, f.area()),
+            AppState::Start(menu, _) => render_start_screen(menu, f.area(), f.buffer_mut()),
+            AppState::Playing(game, _) => f.render_widget(&mut *game, f.area()),
             AppState::Exit => {},
         })?;
 
         // handle input
-        if let AppState::Playing(game) = &app_state {
+        if let AppState::Playing(game, _) = &app_state {
             if get_fps_mode(game) == FpsMode::RealTime {
                 let poll_timeout = cmp::min(dt, target_frame_duration);
                 if event::poll(poll_timeout)? {
@@ -193,10 +257,17 @@ pub fn run_app(terminal: &mut ratatui::DefaultTerminal) -> color_eyre::Result<()
                 // performance mode: block thread until an input event occurs
                 handle_crossterm_events(&mut app_state)?;
             }
-        } else {
-            // For non-playing states (e.g., start menu), use performance mode
-            // to block until input and minimize CPU usage
-            handle_crossterm_events(&mut app_state)?;
+        } else if let AppState::Start(menu, _) = &app_state {
+            // For start menu, use real-time mode only if animation is running
+            if !menu.animation.is_paused() {
+                let poll_timeout = cmp::min(dt, target_frame_duration);
+                if event::poll(poll_timeout)? {
+                    handle_crossterm_events(&mut app_state)?;
+                }
+            } else {
+                // Animation paused, use performance mode to save CPU
+                handle_crossterm_events(&mut app_state)?;
+            }
         }
 
         // cap frame rate
@@ -208,72 +279,116 @@ pub fn run_app(terminal: &mut ratatui::DefaultTerminal) -> color_eyre::Result<()
     Ok(())
 }
 
-fn ascii_art_cells() -> AsciiCells {
+fn ascii_animation() -> ProceduralAnimationWidget {
     let art = indoc! {r#"
          ,,        ,,              ,,
-        *MM        db             *MM                                `7MM
+        *MM        db             *MM      [a: toggle animation]     `7MM
          MM                        MM                                  MM
          MM,dMMb.`7MM  `7MMpMMMb.  MM,dMMb.`7Mb,od8 .gP"Ya   ,6"Yb.    MM  ,MP'
          MM    `Mb MM    MM    MM  MM    `Mb MM' "',M'   Yb 8)   MM    MM ;Y
          MM     M8 MM    MM    MM  MM     M8 MM    8M""""""  ,pm9MM    MM;Mm
          MM.   ,M9 MM    MM    MM  MM.   ,M9 MM    YM.    , 8M   MM    MM `Mb.
          P^YbmdP'.JMML..JMML  JMML.P^YbmdP'.JMML.   `Mbmmd' `Moo9^Yo..JMML. YA.
-    "#};
+    "#}
+    .to_string();
 
-    let colors = indoc! {r#"
-         ,,        ,,              ,,
-        *MM        db             *MM                                `7MM
-         MM                        MM                                  MM
-         MM,dMMb.`7MM  `7MMpMMMb.  MM,dMMb.`7Mb,od8 .gP"Ya   ,6"Yb.    MM  ,MP'
-         MM    `Mb MM    MM    MM  MM    `Mb MM' "',M'   Yb 8)   MM    MM ;Y
-         MM     M8 MM    MM    MM  MM     M8 MM    8M""""""  ,pm9MM    MM;Mm
-         MM.   ,M9 MM    MM    MM  MM.   ,M9 MM    YM.    , 8M   MM    MM `Mb.
-         P^YbmdP'.JMML..JMML  JMML.P^YbmdP'.JMML.   `Mbmmd' `Moo9^Yo..JMML. YA.
-    "#};
+    // Get dimensions for calculations
+    let art_lines: Vec<&str> = art.lines().collect();
+    let height = art_lines.len();
+    let width = art_lines.iter().map(|line| line.len()).max().unwrap_or(0);
 
-    let color_map = HashMap::from([
-        ('M', Color::White),
-        ('b', Color::LightYellow),
-        ('d', Color::LightCyan),
-        ('Y', Color::LightGreen),
-        ('8', Color::LightMagenta),
-        ('*', Color::Magenta),
-        ('`', Color::Cyan),
-        ('6', Color::Green),
-        ('9', Color::Red),
-        ('(', Color::Blue),
-        (')', Color::Blue),
-        (' ', Color::Black),
-    ]);
+    let strip_width = 8.0;
+    let start_offset = -strip_width;
+    let end_offset = (width + height) as f32 + strip_width;
+    let total_range = end_offset - start_offset;
 
-    let default_color = Color::LightBlue;
-    AsciiCells::from(art, colors, &color_map, default_color)
+    // Color function that calculates colors on-the-fly based on animation progress
+    let color_fn =
+        move |x: usize, y: usize, progress: f32, _cycle: usize, highlight_color: Color| -> Color {
+            let offset = start_offset + progress * total_range;
+            let diag_pos = (x + y) as f32;
+            let dist_from_strip = (diag_pos - offset).abs();
+
+            if dist_from_strip < strip_width {
+                highlight_color
+            } else {
+                Color::DarkGray
+            }
+        };
+
+    // Character function that permanently replaces characters with '0' or '1' on first pass,
+    // then reverses them back to original on second pass, creating an infinite loop
+    let char_fn =
+        move |x: usize, y: usize, progress: f32, cycle: usize, original_char: char| -> char {
+            let offset = start_offset + progress * total_range;
+            let diag_pos = (x + y) as f32;
+
+            // Hash function to determine if character is '0' or '1'
+            let mut position_hash = x.wrapping_mul(2654435761);
+            position_hash ^= y.wrapping_mul(2246822519);
+            position_hash = position_hash.wrapping_mul(668265263);
+            position_hash ^= position_hash >> 15;
+
+            let mut binary_hash = position_hash.wrapping_mul(1597334677);
+            binary_hash ^= binary_hash >> 16;
+            let binary_char = if (binary_hash & 1) == 0 { '0' } else { '1' };
+
+            // Even cycles (0, 2, 4...): transform original -> binary
+            // Odd cycles (1, 3, 5...): transform binary -> original
+            let is_forward_pass = cycle.is_multiple_of(2);
+
+            // Check if the strip has passed this character yet
+            let has_strip_passed = diag_pos < offset;
+
+            if is_forward_pass {
+                // Forward pass: if strip has passed, show binary; otherwise show original
+                if has_strip_passed { binary_char } else { original_char }
+            } else {
+                // Reverse pass: if strip has passed, show original; otherwise show binary
+                if has_strip_passed { original_char } else { binary_char }
+            }
+        };
+
+    ProceduralAnimationWidget::new(
+        art,
+        50, // 50 frames worth of timing
+        Duration::from_millis(50),
+        color_fn,
+    )
+    .with_char_fn(char_fn)
+    .with_pause_at_end(Duration::from_secs(2))
 }
 
 // Start menu state
 struct StartMenuState {
     items: Vec<(String, Bits)>,
     list_state: ListState,
+    animation: ProceduralAnimationWidget,
+    number_mode: NumberMode,
 }
 
 impl StartMenuState {
-    fn new() -> Self {
-        Self::with_selected(get_last_selected_index())
+    fn new(prefs: AppPreferences) -> Self {
+        Self::with_preferences(prefs)
     }
 
-    fn with_selected(selected_index: usize) -> Self {
+    fn with_preferences(prefs: AppPreferences) -> Self {
         let items = vec![
-            ("easy       (4 bits)".to_string(), Bits::Four),
-            ("easy Two's complement (4 bits)".to_string(), Bits::FourTwosComplement),
-            ("easy+16    (4 bits*16)".to_string(), Bits::FourShift4),
-            ("easy+256   (4 bits*256)".to_string(), Bits::FourShift8),
-            ("easy+4096  (4 bits*4096)".to_string(), Bits::FourShift12),
-            ("normal     (8 bits)".to_string(), Bits::Eight),
-            ("master     (12 bits)".to_string(), Bits::Twelve),
-            ("insane     (16 bits)".to_string(), Bits::Sixteen),
+            ("nibble_0    4 bit".to_string(), Bits::Four),
+            ("nibble_1    4 bit*16".to_string(), Bits::FourShift4),
+            ("nibble_2    4 bit*256".to_string(), Bits::FourShift8),
+            ("nibble_3    4 bit*4096".to_string(), Bits::FourShift12),
+            ("byte        8 bit".to_string(), Bits::Eight),
+            ("hexlet     12 bit".to_string(), Bits::Twelve),
+            ("word       16 bit".to_string(), Bits::Sixteen),
         ];
 
-        Self { items, list_state: ListState::default().with_selected(Some(selected_index)) }
+        Self {
+            items,
+            list_state: ListState::default().with_selected(Some(prefs.last_selected_index)),
+            animation: ascii_animation(),
+            number_mode: prefs.last_number_mode,
+        }
     }
 
     fn selected_index(&self) -> usize {
@@ -283,9 +398,30 @@ impl StartMenuState {
         self.items[self.selected_index()].1.clone()
     }
     fn select_next(&mut self) {
-        self.list_state.select_next();
+        let current = self.selected_index();
+        let next = if current + 1 >= self.items.len() {
+            current // stay at last item
+        } else {
+            current + 1
+        };
+        self.list_state.select(Some(next));
     }
     fn select_previous(&mut self) {
-        self.list_state.select_previous();
+        let current = self.selected_index();
+        let prev = if current == 0 {
+            0 // stay at first item
+        } else {
+            current - 1
+        };
+        self.list_state.select(Some(prev));
+    }
+    fn toggle_animation(&mut self) {
+        self.animation.toggle_pause();
+    }
+    fn toggle_number_mode(&mut self) {
+        self.number_mode = match self.number_mode {
+            NumberMode::Unsigned => NumberMode::Signed,
+            NumberMode::Signed => NumberMode::Unsigned,
+        };
     }
 }

src/binary_numbers.rs

@@ -1,3 +1,4 @@
+use crate::app::{NumberMode, get_mode_color};
 use crate::keybinds;
 use crate::main_screen_widget::{MainScreenWidget, WidgetRef};
 use crate::utils::{When, center};
@@ -24,6 +25,7 @@ struct StatsSnapshot {
     rounds: u32,
     lives: u32,
     bits: Bits,
+    number_mode: NumberMode,
     hearts: String,
     game_state: GameState,
     prev_high_score: u32,
@@ -94,11 +96,10 @@ impl BinaryNumbersPuzzle {
                 Span::styled(format!("Hi-Score: {}  ", stats.prev_high_score), style)
             };
 
+            let mode_color = get_mode_color(&stats.bits);
+            let mode_label = format!("{} {}", stats.bits.label(), stats.number_mode.label());
             let line1 = Line::from(vec![
-                Span::styled(
-                    format!("Mode: {}  ", stats.bits.label()),
-                    Style::default().fg(Color::Yellow),
-                ),
+                Span::styled(format!("Mode: {}  ", mode_label), Style::default().fg(mode_color)),
                 high_label,
             ]);
 
@@ -190,13 +191,7 @@ impl BinaryNumbersPuzzle {
 
             Block::bordered().border_type(border_type).fg(border_color).render(area, buf);
 
-            let suggestion_str = if self.bits.is_twos_complement() {
-                // Convert raw bit pattern to signed value for display
-                let signed_val = self.bits.raw_to_signed(*suggestion);
-                format!("{signed_val}")
-            } else {
-                format!("{suggestion}")
-            };
+            let suggestion_str = format!("{suggestion}");
 
             #[allow(clippy::cast_possible_truncation)]
             Paragraph::new(suggestion_str.to_string())
@@ -374,6 +369,7 @@ fn render_game_over(
 pub struct BinaryNumbersGame {
     puzzle: BinaryNumbersPuzzle,
     bits: Bits,
+    number_mode: NumberMode,
     exit_intended: bool,
     score: u32,
     streak: u32,
@@ -418,15 +414,17 @@ impl MainScreenWidget for BinaryNumbersGame {
 }
 
 impl BinaryNumbersGame {
-    pub fn new(bits: Bits) -> Self {
-        Self::new_with_max_lives(bits, 3)
+    pub fn new(bits: Bits, number_mode: NumberMode) -> Self {
+        Self::new_with_max_lives(bits, number_mode, 3)
     }
-    pub fn new_with_max_lives(bits: Bits, max_lives: u32) -> Self {
+    pub fn new_with_max_lives(bits: Bits, number_mode: NumberMode, max_lives: u32) -> Self {
         let hs = HighScores::load();
-        let starting_prev = hs.get(bits.high_score_key());
+        let high_score_key = Self::compute_high_score_key(&bits, number_mode);
+        let starting_prev = hs.get(&high_score_key);
         let mut game = Self {
             bits: bits.clone(),
-            puzzle: Self::init_puzzle(bits, 0),
+            number_mode,
+            puzzle: Self::init_puzzle(bits, number_mode, 0),
             exit_intended: false,
             score: 0,
             streak: 0,
@@ -445,8 +443,17 @@ impl BinaryNumbersGame {
         game
     }
 
-    pub fn init_puzzle(bits: Bits, streak: u32) -> BinaryNumbersPuzzle {
-        BinaryNumbersPuzzle::new(bits, streak)
+    pub fn init_puzzle(bits: Bits, number_mode: NumberMode, streak: u32) -> BinaryNumbersPuzzle {
+        BinaryNumbersPuzzle::new(bits, number_mode, streak)
+    }
+
+    fn compute_high_score_key(bits: &Bits, number_mode: NumberMode) -> String {
+        let bits_key = bits.high_score_key();
+        let mode_suffix = match number_mode {
+            NumberMode::Unsigned => "u",
+            NumberMode::Signed => "s",
+        };
+        format!("{}{}", bits_key, mode_suffix)
     }
 
     pub fn is_active(&self) -> bool {
@@ -489,13 +496,13 @@ impl BinaryNumbersGame {
                 },
             }
             // high score update
-            let bits_key = self.bits.high_score_key();
-            let prev = self.high_scores.get(bits_key);
+            let bits_key = Self::compute_high_score_key(&self.bits, self.number_mode);
+            let prev = self.high_scores.get(&bits_key);
             if self.score > prev {
                 if !self.new_high_score_reached {
                     self.prev_high_score_for_display = prev;
                 }
-                self.high_scores.update(bits_key, self.score);
+                self.high_scores.update(&bits_key, self.score);
                 self.new_high_score_reached = true;
                 let _ = self.high_scores.save();
             }
@@ -544,9 +551,10 @@ impl BinaryNumbersGame {
         self.lives = self.max_lives.min(3);
         self.game_state = GameState::Active;
         self.max_streak = 0;
-        self.prev_high_score_for_display = self.high_scores.get(self.bits.high_score_key());
+        let high_score_key = Self::compute_high_score_key(&self.bits, self.number_mode);
+        self.prev_high_score_for_display = self.high_scores.get(&high_score_key);
         self.new_high_score_reached = false;
-        self.puzzle = Self::init_puzzle(self.bits.clone(), 0);
+        self.puzzle = Self::init_puzzle(self.bits.clone(), self.number_mode, 0);
         self.puzzle_resolved = false;
         self.refresh_stats_snapshot();
     }
@@ -609,7 +617,8 @@ impl BinaryNumbersGame {
                     },
                     GameState::Result => {
                         // start next puzzle
-                        self.puzzle = Self::init_puzzle(self.bits.clone(), self.streak);
+                        self.puzzle =
+                            Self::init_puzzle(self.bits.clone(), self.number_mode, self.streak);
                         self.puzzle_resolved = false;
                         self.game_state = GameState::Active;
                     },
@@ -630,6 +639,7 @@ impl BinaryNumbersGame {
             rounds: self.rounds,
             lives: self.lives,
             bits: self.bits.clone(),
+            number_mode: self.number_mode,
             hearts: self.lives_hearts(),
             game_state: self.game_state,
             prev_high_score: self.prev_high_score_for_display,
@@ -648,7 +658,6 @@ enum GuessResult {
 #[derive(Clone)]
 pub enum Bits {
     Four,
-    FourTwosComplement,
     FourShift4,
     FourShift8,
     FourShift12,
@@ -660,11 +669,7 @@ pub enum Bits {
 impl Bits {
     pub const fn to_int(&self) -> u32 {
         match self {
-            Self::Four
-            | Self::FourShift4
-            | Self::FourShift8
-            | Self::FourShift12
-            | Self::FourTwosComplement => 4,
+            Self::Four | Self::FourShift4 | Self::FourShift8 | Self::FourShift12 => 4,
             Self::Eight => 8,
             Self::Twelve => 12,
             Self::Sixteen => 16,
@@ -673,7 +678,6 @@ impl Bits {
     pub const fn scale_factor(&self) -> u32 {
         match self {
             Self::Four => 1,
-            Self::FourTwosComplement => 1,
             Self::FourShift4 => 16,
             Self::FourShift8 => 256,
             Self::FourShift12 => 4096,
@@ -685,7 +689,6 @@ impl Bits {
     pub const fn high_score_key(&self) -> u32 {
         match self {
             Self::Four => 4,
-            Self::FourTwosComplement => 42, // separate key for two's complement
             Self::FourShift4 => 44,
             Self::FourShift8 => 48,
             Self::FourShift12 => 412,
@@ -699,11 +702,7 @@ impl Bits {
     }
     pub const fn suggestion_count(&self) -> usize {
         match self {
-            Self::Four
-            | Self::FourShift4
-            | Self::FourShift8
-            | Self::FourShift12
-            | Self::FourTwosComplement => 3,
+            Self::Four | Self::FourShift4 | Self::FourShift8 | Self::FourShift12 => 3,
             Self::Eight => 4,
             Self::Twelve => 5,
             Self::Sixteen => 6,
@@ -711,39 +710,26 @@ impl Bits {
     }
     pub const fn label(&self) -> &'static str {
         match self {
-            Self::Four => "4 bits",
-            Self::FourTwosComplement => "4 bits (Two's complement)",
-            Self::FourShift4 => "4 bits*16",
-            Self::FourShift8 => "4 bits*256",
-            Self::FourShift12 => "4 bits*4096",
-            Self::Eight => "8 bits",
-            Self::Twelve => "12 bits",
-            Self::Sixteen => "16 bits",
+            Self::Four => "4 bit",
+            Self::FourShift4 => "4 bit*16",
+            Self::FourShift8 => "4 bit*256",
+            Self::FourShift12 => "4 bit*4096",
+            Self::Eight => "8 bit",
+            Self::Twelve => "12 bit",
+            Self::Sixteen => "16 bit",
         }
     }
-
-    /// Convert raw bit pattern to signed value for two's complement mode
-    pub const fn raw_to_signed(&self, raw: u32) -> i32 {
-        match self {
-            Self::FourTwosComplement => {
-                // 4-bit two's complement: range -8 to +7
-                if raw >= 8 { (raw as i32) - 16 } else { raw as i32 }
-            },
-            _ => raw as i32, // other modes use unsigned
-        }
-    }
-
-    pub const fn is_twos_complement(&self) -> bool {
-        matches!(self, Self::FourTwosComplement)
-    }
 }
 
 pub struct BinaryNumbersPuzzle {
     bits: Bits,
-    current_number: u32,     // scaled value used for suggestions matching
+    #[allow(dead_code)]
+    number_mode: NumberMode,
+    #[allow(dead_code)]
+    current_number: u32, // scaled value used for suggestions matching
     raw_current_number: u32, // raw bit value (unscaled) for display
-    suggestions: Vec<u32>,
-    selected_suggestion: Option<u32>,
+    suggestions: Vec<i32>,   // Changed to i32 to support signed values
+    selected_suggestion: Option<i32>,
     time_total: f64,
     time_left: f64,
     guess_result: Option<GuessResult>,
@@ -753,62 +739,81 @@ pub struct BinaryNumbersPuzzle {
 }
 
 impl BinaryNumbersPuzzle {
-    pub fn new(bits: Bits, streak: u32) -> Self {
+    pub fn new(bits: Bits, number_mode: NumberMode, streak: u32) -> Self {
         let mut rng = rand::rng();
 
         let mut suggestions = Vec::new();
         let scale = bits.scale_factor();
+        let num_bits = bits.to_int();
 
-        if bits.is_twos_complement() {
-            // For two's complement, generate unique raw bit patterns (0-15)
-            let mut raw_values: Vec<u32> = Vec::new();
-            while raw_values.len() < bits.suggestion_count() {
-                let raw = rng.random_range(0..u32::pow(2, bits.to_int()));
-                if !raw_values.contains(&raw) {
-                    raw_values.push(raw);
+        match number_mode {
+            NumberMode::Unsigned => {
+                while suggestions.len() < bits.suggestion_count() {
+                    let raw = rng.random_range(0..u32::pow(2, num_bits));
+                    let num = (raw * scale) as i32;
+                    if !suggestions.contains(&num) {
+                        suggestions.push(num);
+                    }
                 }
-            }
-            // Store raw bit patterns directly
-            suggestions = raw_values;
-        } else {
-            // For unsigned modes
-            while suggestions.len() < bits.suggestion_count() {
-                let raw = rng.random_range(0..u32::pow(2, bits.to_int()));
-                let num = raw * scale;
-                if !suggestions.contains(&num) {
-                    suggestions.push(num);
+            },
+            NumberMode::Signed => {
+                // For signed mode, use two's complement representation
+                // Range is from -(2^(n-1)) to 2^(n-1)-1
+                while suggestions.len() < bits.suggestion_count() {
+                    let raw = rng.random_range(0..u32::pow(2, num_bits));
+                    // Convert raw bits to signed value using two's complement
+                    let signed_val = if raw >= (1 << (num_bits - 1)) {
+                        // Negative number: raw - 2^n
+                        (raw as i32) - (1 << num_bits)
+                    } else {
+                        // Positive number
+                        raw as i32
+                    };
+                    let num = signed_val * (scale as i32);
+                    if !suggestions.contains(&num) {
+                        suggestions.push(num);
+                    }
                 }
-            }
+            },
         }
 
-        let current_number = suggestions[0]; // scaled value or raw for twos complement
-        let raw_current_number = if bits.is_twos_complement() {
-            current_number // for two's complement, it's already the raw bit pattern
-        } else {
-            current_number / scale // back-calculate raw bits
-        };
+        // Shuffle suggestions
         suggestions.shuffle(&mut rng);
 
-        // Base time by bits + difficulty scaling (shorter as streak increases)
-        let base_time = match bits {
-            Bits::Four
-            | Bits::FourShift4
-            | Bits::FourShift8
-            | Bits::FourShift12
-            | Bits::FourTwosComplement => 8.0,
-            Bits::Eight => 12.0,
-            Bits::Twelve => 16.0,
-            Bits::Sixteen => 20.0,
+        // Pick first suggestion as the current number
+        let current_number_signed = suggestions[0];
+
+        // Calculate raw_current_number based on mode
+        let raw_current_number = match number_mode {
+            NumberMode::Unsigned => {
+                let current_number = current_number_signed.unsigned_abs();
+                current_number / scale
+            },
+            NumberMode::Signed => {
+                // For signed mode, we need to preserve the two's complement representation
+                // First, get the unscaled signed value
+                let unscaled_signed = current_number_signed / (scale as i32);
+
+                // Convert to unsigned bits using two's complement masking
+                // For n-bit number, mask is (2^n - 1)
+                let mask = (1u32 << num_bits) - 1;
+                (unscaled_signed as u32) & mask
+            },
         };
-        let penalty = f64::from(streak) * 0.5; // 0.5s less per streak
-        let time_total = (base_time - penalty).max(5.0);
+
+        let current_number = current_number_signed.unsigned_abs();
+
+        // Calculate time based on difficulty
+        let time_total = 10.0 - (streak.min(8) as f64 * 0.5);
         let time_left = time_total;
+
         let selected_suggestion = Some(suggestions[0]);
         let guess_result = None;
         let last_points_awarded = 0;
 
         Self {
             bits,
+            number_mode,
             current_number,
             raw_current_number,
             suggestions,
@@ -818,15 +823,16 @@ impl BinaryNumbersPuzzle {
             guess_result,
             last_points_awarded,
             stats_snapshot: None,
-            skip_first_dt: true, // Skip first dt to prevent timer jump
+            skip_first_dt: true,
         }
     }
 
-    pub fn suggestions(&self) -> &[u32] {
+    pub fn suggestions(&self) -> &[i32] {
         &self.suggestions
     }
-    pub const fn is_correct_guess(&self, guess: u32) -> bool {
-        guess == self.current_number
+
+    pub fn is_correct_guess(&self, guess: i32) -> bool {
+        guess == self.suggestions[0]
     }
 
     pub fn current_to_binary_string(&self) -> String {
@@ -841,19 +847,14 @@ impl BinaryNumbersPuzzle {
     }
 
     pub fn run(&mut self, dt: f64) {
-        if self.guess_result.is_some() {
-            // If a guess has been made, we don't need to run the game logic anymore.
-            return;
-        }
-
-        // Skip first dt to prevent timer jump when starting new puzzle
         if self.skip_first_dt {
             self.skip_first_dt = false;
             return;
         }
-
-        self.time_left = (self.time_left - dt).max(0.0);
-
+        if self.guess_result.is_some() {
+            return;
+        }
+        self.time_left -= dt;
         if self.time_left <= 0.0 {
             self.guess_result = Some(GuessResult::Timeout);
         }
@@ -894,7 +895,7 @@ fn render_ascii_gauge(area: Rect, buf: &mut Buffer, ratio: f64, color: Color) {
 }
 
 struct HighScores {
-    scores: HashMap<u32, u32>,
+    scores: HashMap<String, u32>,
 }
 
 impl HighScores {
@@ -911,10 +912,9 @@ impl HighScores {
             if file.read_to_string(&mut contents).is_ok() {
                 for line in contents.lines() {
                     if let Some((k, v)) = line.split_once('=')
-                        && let Ok(bits) = k.trim().parse::<u32>()
                         && let Ok(score) = v.trim().parse::<u32>()
                     {
-                        hs.scores.insert(bits, score);
+                        hs.scores.insert(k.trim().to_string(), score);
                     }
                 }
             }
@@ -924,7 +924,10 @@ impl HighScores {
 
     fn save(&self) -> std::io::Result<()> {
         let mut data = String::new();
-        for key in [4u32, 42u32, 44u32, 48u32, 412u32, 8u32, 12u32, 16u32] {
+        for key in [
+            "4u", "4s", "44u", "44s", "48u", "48s", "412u", "412s", "8u", "8s", "12u", "12s",
+            "16u", "16s",
+        ] {
             let val = self.get(key);
             let _ = writeln!(data, "{key}={val}");
         }
@@ -932,12 +935,12 @@ impl HighScores {
         file.write_all(data.as_bytes())
     }
 
-    fn get(&self, bits: u32) -> u32 {
-        *self.scores.get(&bits).unwrap_or(&0)
+    fn get(&self, bits: &str) -> u32 {
+        *self.scores.get(bits).unwrap_or(&0)
     }
 
-    fn update(&mut self, bits: u32, score: u32) {
-        self.scores.insert(bits, score);
+    fn update(&mut self, bits: &str, score: u32) {
+        self.scores.insert(bits.to_string(), score);
     }
 }
 
@@ -951,7 +954,8 @@ mod tests {
     static HS_LOCK: Mutex<()> = Mutex::new(());
 
     fn with_high_score_file<F: FnOnce()>(f: F) {
-        let _guard = HS_LOCK.lock().unwrap();
+        #[allow(clippy::expect_used)]
+        let _guard = HS_LOCK.lock().expect("Failed to lock high score mutex");
         let original = fs::read_to_string(HighScores::FILE).ok();
         f();
         // restore
@@ -984,7 +988,7 @@ mod tests {
 
     #[test]
     fn puzzle_generation_unique_and_scaled() {
-        let p = BinaryNumbersPuzzle::new(Bits::FourShift4.clone(), 0);
+        let p = BinaryNumbersPuzzle::new(Bits::FourShift4.clone(), NumberMode::Unsigned, 0);
         let scale = Bits::FourShift4.scale_factor();
         assert_eq!(p.suggestions().len(), Bits::FourShift4.suggestion_count());
         // uniqueness
@@ -995,26 +999,81 @@ mod tests {
         }
         // scaling property
         for &s in p.suggestions() {
-            assert_eq!(s % scale, 0);
+            assert_eq!(s.unsigned_abs() % scale, 0);
         }
         // current number must be one of suggestions and raw_current_number * scale == current_number
-        assert!(p.suggestions().contains(&p.current_number));
+        assert!(p.suggestions().contains(&(p.current_number as i32)));
         assert_eq!(p.raw_current_number * scale, p.current_number);
     }
 
     #[test]
     fn binary_string_formatting_groups_every_four_bits() {
-        let mut p = BinaryNumbersPuzzle::new(Bits::Eight, 0);
+        let mut p = BinaryNumbersPuzzle::new(Bits::Eight, NumberMode::Unsigned, 0);
         p.raw_current_number = 0xAB; // 171 = 10101011
         assert_eq!(p.current_to_binary_string(), "1010 1011");
-        let mut p4 = BinaryNumbersPuzzle::new(Bits::Four, 0);
+        let mut p4 = BinaryNumbersPuzzle::new(Bits::Four, NumberMode::Unsigned, 0);
         p4.raw_current_number = 0b0101;
         assert_eq!(p4.current_to_binary_string(), "0101");
     }
 
+    #[test]
+    fn signed_mode_negative_numbers_show_sign_bit() {
+        // Test 4-bit signed mode with a negative number
+        let mut p = BinaryNumbersPuzzle::new(Bits::Four, NumberMode::Signed, 0);
+        // In 4-bit two's complement, -8 is represented as 1000
+        p.raw_current_number = 0b1000; // -8 in 4-bit two's complement
+        assert_eq!(p.current_to_binary_string(), "1000", "4-bit: -8 should be 1000");
+
+        // In 4-bit two's complement, -1 is represented as 1111
+        p.raw_current_number = 0b1111; // -1 in 4-bit two's complement
+        assert_eq!(p.current_to_binary_string(), "1111", "4-bit: -1 should be 1111");
+
+        // Test 8-bit signed mode with a negative number
+        let mut p8 = BinaryNumbersPuzzle::new(Bits::Eight, NumberMode::Signed, 0);
+        // In 8-bit two's complement, -128 is represented as 10000000
+        p8.raw_current_number = 0b10000000; // -128 in 8-bit two's complement
+        assert_eq!(p8.current_to_binary_string(), "1000 0000", "8-bit: -128 should be 1000 0000");
+
+        // In 8-bit two's complement, -1 is represented as 11111111
+        p8.raw_current_number = 0b11111111; // -1 in 8-bit two's complement
+        assert_eq!(p8.current_to_binary_string(), "1111 1111", "8-bit: -1 should be 1111 1111");
+    }
+
+    #[test]
+    fn signed_mode_puzzle_generates_correct_raw_bits_for_negative() {
+        // Generate many puzzles and check that when we have a negative number,
+        // the raw_current_number has the sign bit set correctly
+        for _ in 0..20 {
+            let p = BinaryNumbersPuzzle::new(Bits::Four, NumberMode::Signed, 0);
+            let current_signed = p.suggestions[0];
+
+            if current_signed < 0 {
+                // For negative numbers in 4-bit two's complement, the MSB (bit 3) should be 1
+                // which means raw_current_number should be >= 8 (0b1000)
+                assert!(
+                    p.raw_current_number >= 8,
+                    "Negative number {} should have raw bits >= 8 (sign bit set), but got {}. Binary: {}",
+                    current_signed,
+                    p.raw_current_number,
+                    p.current_to_binary_string()
+                );
+            } else {
+                // For positive numbers (including 0), MSB should be 0
+                // which means raw_current_number should be < 8
+                assert!(
+                    p.raw_current_number < 8,
+                    "Positive number {} should have raw bits < 8 (sign bit clear), but got {}. Binary: {}",
+                    current_signed,
+                    p.raw_current_number,
+                    p.current_to_binary_string()
+                );
+            }
+        }
+    }
+
     #[test]
     fn puzzle_timeout_sets_guess_result() {
-        let mut p = BinaryNumbersPuzzle::new(Bits::Four, 0);
+        let mut p = BinaryNumbersPuzzle::new(Bits::Four, NumberMode::Unsigned, 0);
         p.time_left = 0.5;
         // First run() skips dt due to skip_first_dt flag
         // The reason for this is to prevent timer jump when starting a new puzzle
@@ -1028,9 +1087,9 @@ mod tests {
     #[test]
     fn finalize_round_correct_increments_score_streak_and_sets_result_state() {
         with_high_score_file(|| {
-            let mut g = BinaryNumbersGame::new(Bits::Four);
+            let mut g = BinaryNumbersGame::new(Bits::Four, NumberMode::Unsigned);
             // ensure deterministic: mark puzzle correct
-            let answer = g.puzzle.current_number;
+            let answer = g.puzzle.current_number as i32;
             g.puzzle.guess_result = Some(GuessResult::Correct);
             g.finalize_round();
             assert_eq!(g.streak, 1);
@@ -1045,7 +1104,7 @@ mod tests {
     #[test]
     fn life_awarded_every_five_streak() {
         with_high_score_file(|| {
-            let mut g = BinaryNumbersGame::new_with_max_lives(Bits::Four, 3);
+            let mut g = BinaryNumbersGame::new_with_max_lives(Bits::Four, NumberMode::Unsigned, 3);
             g.lives = 2; // below max
             g.streak = 4; // about to become 5
             g.puzzle.guess_result = Some(GuessResult::Correct);
@@ -1058,7 +1117,7 @@ mod tests {
     #[test]
     fn incorrect_guess_resets_streak_and_loses_life() {
         with_high_score_file(|| {
-            let mut g = BinaryNumbersGame::new(Bits::Four);
+            let mut g = BinaryNumbersGame::new(Bits::Four, NumberMode::Unsigned);
             g.streak = 3;
             let lives_before = g.lives;
             g.puzzle.guess_result = Some(GuessResult::Incorrect);
@@ -1071,7 +1130,7 @@ mod tests {
     #[test]
     fn pending_game_over_when_life_reaches_zero() {
         with_high_score_file(|| {
-            let mut g = BinaryNumbersGame::new(Bits::Four);
+            let mut g = BinaryNumbersGame::new(Bits::Four, NumberMode::Unsigned);
             g.lives = 1;
             g.puzzle.guess_result = Some(GuessResult::Incorrect);
             g.finalize_round();
@@ -1083,28 +1142,29 @@ mod tests {
     #[test]
     fn high_score_updates_and_flag_set() {
         with_high_score_file(|| {
-            let mut g = BinaryNumbersGame::new(Bits::Four);
+            let mut g = BinaryNumbersGame::new(Bits::Four, NumberMode::Unsigned);
             // Force previous high score low
-            g.high_scores.update(g.bits.high_score_key(), 5);
+            let key = BinaryNumbersGame::compute_high_score_key(&g.bits, g.number_mode);
+            g.high_scores.update(&key, 5);
             g.prev_high_score_for_display = 5;
             g.puzzle.guess_result = Some(GuessResult::Correct);
             g.finalize_round();
             assert!(g.new_high_score_reached);
-            assert!(g.high_scores.get(g.bits.high_score_key()) >= 10);
+            assert!(g.high_scores.get(&key) >= 10);
             assert_eq!(g.prev_high_score_for_display, 5); // previous stored
         });
     }
 
     #[test]
     fn hearts_representation_matches_lives() {
-        let mut g = BinaryNumbersGame::new_with_max_lives(Bits::Four, 3);
+        let mut g = BinaryNumbersGame::new_with_max_lives(Bits::Four, NumberMode::Unsigned, 3);
         g.lives = 2;
         assert_eq!(g.lives_hearts(), "♥♥·");
     }
 
     #[test]
     fn handle_input_navigation_changes_selected_suggestion() {
-        let mut g = BinaryNumbersGame::new(Bits::Four);
+        let mut g = BinaryNumbersGame::new(Bits::Four, NumberMode::Unsigned);
         let initial = g.puzzle.selected_suggestion;
         // Simulate Right key
         let right_event = KeyEvent {

src/utils.rs

@@ -1,85 +1,179 @@
 use ratatui::layout::Flex;
 use ratatui::prelude::*;
-use std::collections::HashMap;
+use std::time::{Duration, Instant};
 
-pub struct AsciiCell {
-    pub ch: char,
-    pub x: u16,
-    pub y: u16,
-    pub color: Color,
+/// Type alias for the color function used in procedural animations
+type ColorFn = Box<dyn Fn(usize, usize, f32, usize, Color) -> Color>;
+
+/// Type alias for the character transformation function
+type CharFn = Box<dyn Fn(usize, usize, f32, usize, char) -> char>;
+
+/// A procedural animation widget that calculates colors on-the-fly
+/// This is much more memory efficient than storing multiple frames
+pub struct ProceduralAnimationWidget {
+    art: String,
+    width: u16,
+    height: u16,
+    num_frames: usize,
+    frame_duration: Duration,
+    pause_at_end: Duration,
+    start_time: Instant,
+    paused: bool,
+    paused_progress: f32,
+    paused_cycle: usize,
+    highlight_color: Color,  // The color for the animated strip
+    color_fn: ColorFn,       // (x, y, progress, cycle, highlight_color) -> Color
+    char_fn: Option<CharFn>, // (x, y, progress, cycle, original_char) -> char
 }
 
-#[allow(clippy::cast_possible_truncation)]
-pub fn parse_ascii_art(
-    art: &str,
-    color_map_str: &str,
-    color_map: &HashMap<char, Color>,
-    default_color: Color,
-) -> Vec<AsciiCell> {
-    let art_lines: Vec<Vec<char>> = art.lines().map(|line| line.chars().collect()).collect();
-    let color_lines: Vec<Vec<char>> =
-        color_map_str.lines().map(|line| line.chars().collect()).collect();
+impl ProceduralAnimationWidget {
+    pub fn new(
+        art: String,
+        num_frames: usize,
+        frame_duration: Duration,
+        color_fn: impl Fn(usize, usize, f32, usize, Color) -> Color + 'static,
+    ) -> Self {
+        let art_lines: Vec<&str> = art.lines().collect();
+        let height = art_lines.len() as u16;
+        let width = art_lines.iter().map(|line| line.len()).max().unwrap_or(0) as u16;
 
-    assert_eq!(art_lines.len(), color_lines.len(), "Art and color string must have same height");
-
-    let mut pixels = Vec::new();
-
-    for (y, (art_row, color_row)) in art_lines.iter().zip(color_lines.iter()).enumerate() {
-        assert_eq!(art_row.len(), color_row.len(), "Mismatched line lengths");
-
-        for (x, (&ch, &color_ch)) in art_row.iter().zip(color_row.iter()).enumerate() {
-            let color = color_map.get(&color_ch).copied().unwrap_or(default_color);
-            pixels.push(AsciiCell { ch, x: x as u16, y: y as u16, color });
+        Self {
+            art,
+            width,
+            height,
+            num_frames,
+            frame_duration,
+            pause_at_end: Duration::ZERO,
+            start_time: Instant::now(),
+            paused: false,
+            paused_progress: 0.0,
+            paused_cycle: 0,
+            highlight_color: Color::LightGreen, // Default color
+            color_fn: Box::new(color_fn),
+            char_fn: None,
         }
     }
 
-    pixels
-}
-
-pub struct AsciiCells {
-    pub cells: Vec<AsciiCell>,
-}
-
-impl AsciiCells {
-    pub fn from(
-        art: &str,
-        color_map_str: &str,
-        color_map: &HashMap<char, Color>,
-        default_color: Color,
+    pub fn with_char_fn(
+        mut self,
+        char_fn: impl Fn(usize, usize, f32, usize, char) -> char + 'static,
     ) -> Self {
-        Self { cells: parse_ascii_art(art, color_map_str, color_map, default_color) }
+        self.char_fn = Some(Box::new(char_fn));
+        self
+    }
+
+    pub fn with_pause_at_end(mut self, pause: Duration) -> Self {
+        self.pause_at_end = pause;
+        self
+    }
+
+    pub fn pause(&mut self) {
+        if !self.paused {
+            let (progress, cycle) = self.get_animation_progress_and_cycle();
+            self.paused_progress = progress;
+            self.paused_cycle = cycle;
+            self.paused = true;
+        }
+    }
+
+    pub fn unpause(&mut self) {
+        if self.paused {
+            // Adjust start_time so that the animation continues from paused_progress
+            let animation_duration = self.frame_duration * self.num_frames as u32;
+            let total_cycle_duration = animation_duration + self.pause_at_end;
+            let elapsed_at_pause = Duration::from_millis(
+                (self.paused_cycle as f32 * total_cycle_duration.as_millis() as f32
+                    + self.paused_progress * animation_duration.as_millis() as f32)
+                    as u64,
+            );
+            self.start_time = Instant::now() - elapsed_at_pause;
+            self.paused = false;
+        }
+    }
+
+    pub fn toggle_pause(&mut self) {
+        if self.paused {
+            self.unpause();
+        } else {
+            self.pause();
+        }
+    }
+
+    pub fn is_paused(&self) -> bool {
+        self.paused
     }
 
     pub fn get_width(&self) -> u16 {
-        self.cells.iter().map(|cell| cell.x).max().unwrap_or(0) + 1
+        self.width
     }
 
     pub fn get_height(&self) -> u16 {
-        self.cells.iter().map(|cell| cell.y).max().unwrap_or(0) + 1
+        self.height
     }
-}
 
-pub struct AsciiArtWidget {
-    collection: AsciiCells,
-}
-
-impl AsciiArtWidget {
-    pub const fn new(collection: AsciiCells) -> Self {
-        Self { collection }
+    /// Set the highlight color for the animation
+    pub fn set_highlight_color(&mut self, color: Color) {
+        self.highlight_color = color;
     }
-}
 
-impl Widget for AsciiArtWidget {
-    fn render(self, area: Rect, buf: &mut Buffer) {
-        for pixel in self.collection.cells {
-            let position = Position::new(pixel.x + area.x, pixel.y + area.y);
+    fn get_animation_progress_and_cycle(&self) -> (f32, usize) {
+        if self.paused {
+            return (self.paused_progress, self.paused_cycle);
+        }
 
-            if area.contains(position) {
-                #[allow(clippy::expect_used)]
-                buf.cell_mut(position)
-                    .expect("Failed to get cell at position")
-                    .set_char(pixel.ch)
-                    .set_fg(pixel.color);
+        let elapsed = self.start_time.elapsed();
+        let animation_duration = self.frame_duration * self.num_frames as u32;
+        let total_cycle_duration = animation_duration + self.pause_at_end;
+
+        let cycle = (elapsed.as_millis() / total_cycle_duration.as_millis()) as usize;
+        let cycle_time = elapsed.as_millis() % total_cycle_duration.as_millis();
+
+        // If we're in the pause period, return 1.0 (end of animation)
+        if cycle_time >= animation_duration.as_millis() {
+            return (1.0, cycle);
+        }
+
+        // Otherwise calculate progress through animation
+        let progress = cycle_time as f32 / animation_duration.as_millis() as f32;
+        (progress, cycle)
+    }
+
+    pub fn render_to_buffer(&self, area: Rect, buf: &mut Buffer) {
+        let (progress, cycle) = self.get_animation_progress_and_cycle();
+        self.render_to_buffer_at_progress(area, buf, progress, cycle);
+    }
+
+    pub fn render_to_buffer_at_progress(
+        &self,
+        area: Rect,
+        buf: &mut Buffer,
+        progress: f32,
+        cycle: usize,
+    ) {
+        for (y, line) in self.art.lines().enumerate() {
+            for (x, ch) in line.chars().enumerate() {
+                if ch == ' ' {
+                    continue; // Skip spaces
+                }
+
+                let color = (self.color_fn)(x, y, progress, cycle, self.highlight_color);
+
+                // Apply character transformation if char_fn is provided
+                let display_char = if let Some(ref char_fn) = self.char_fn {
+                    char_fn(x, y, progress, cycle, ch)
+                } else {
+                    ch
+                };
+
+                let position = Position::new(x as u16 + area.x, y as u16 + area.y);
+
+                if area.contains(position) {
+                    #[allow(clippy::expect_used)]
+                    buf.cell_mut(position)
+                        .expect("Failed to get cell at position")
+                        .set_char(display_char)
+                        .set_fg(color);
+                }
             }
         }
     }