feat: collision helper, ghost/pacman collision events, collision tests

minor format updates from copilot's commit

src/game.rs

@@ -251,14 +251,13 @@ impl Game {
                  backbuffer: NonSendMut<BackbufferResource>,
                  debug_state: Res<DebugState>,
                  mut dirty: ResMut<RenderDirty>| {
-                    if dirty.0 || *debug_state != DebugState::Off {
+                    if dirty.0 || debug_state.enabled {
                         // Only copy backbuffer to main canvas if debug rendering is off
                         // (debug rendering draws directly to main canvas)
-                        if *debug_state == DebugState::Off {
-                            canvas.copy(&backbuffer.0, None, None).unwrap();
+                        if !debug_state.enabled {
+                            canvas.present();
                         }
                         dirty.0 = false;
-                        canvas.present();
                     }
                 },
             ),

src/platform/mod.rs

@@ -28,7 +28,6 @@ pub trait CommonPlatform {
     fn get_canvas_size(&self) -> Option<(u32, u32)>;
 
     /// Loads raw asset data using the appropriate platform-specific method.
-
     fn get_asset_bytes(&self, asset: Asset) -> Result<Cow<'static, [u8]>, AssetError>;
 }
 

src/systems/collision.rs

@@ -6,9 +6,28 @@ use bevy_ecs::system::{Query, Res};
 use crate::error::GameError;
 use crate::events::GameEvent;
 use crate::map::builder::Map;
-use crate::systems::components::{Collider, ItemCollider, PacmanCollider};
+use crate::systems::components::{Collider, GhostCollider, ItemCollider, PacmanCollider};
 use crate::systems::movement::Position;
 
+/// Helper function to check collision between two entities with colliders.
+pub fn check_collision(
+    pos1: &Position,
+    collider1: &Collider,
+    pos2: &Position,
+    collider2: &Collider,
+    map: &Map,
+) -> Result<bool, GameError> {
+    let pixel1 = pos1
+        .get_pixel_position(&map.graph)
+        .map_err(|e| GameError::InvalidState(format!("Failed to get pixel position for entity 1: {}", e)))?;
+    let pixel2 = pos2
+        .get_pixel_position(&map.graph)
+        .map_err(|e| GameError::InvalidState(format!("Failed to get pixel position for entity 2: {}", e)))?;
+
+    let distance = pixel1.distance(pixel2);
+    Ok(collider1.collides_with(collider2.size, distance))
+}
+
 /// Detects overlapping entities and generates collision events for gameplay systems.
 ///
 /// Performs distance-based collision detection between Pac-Man and collectible items
@@ -16,42 +35,49 @@ use crate::systems::movement::Position;
 /// a `GameEvent::Collision` for the item system to handle scoring and removal.
 /// Collision detection accounts for both entities being in motion and supports
 /// circular collision boundaries for accurate gameplay feel.
+///
+/// Also detects collisions between Pac-Man and ghosts for gameplay mechanics like
+/// power pellet effects, ghost eating, and player death.
 pub fn collision_system(
     map: Res<Map>,
     pacman_query: Query<(Entity, &Position, &Collider), With<PacmanCollider>>,
     item_query: Query<(Entity, &Position, &Collider), With<ItemCollider>>,
+    ghost_query: Query<(Entity, &Position, &Collider), With<GhostCollider>>,
     mut events: EventWriter<GameEvent>,
     mut errors: EventWriter<GameError>,
 ) {
     // Check PACMAN × ITEM collisions
     for (pacman_entity, pacman_pos, pacman_collider) in pacman_query.iter() {
         for (item_entity, item_pos, item_collider) in item_query.iter() {
-            match (
-                pacman_pos.get_pixel_position(&map.graph),
-                item_pos.get_pixel_position(&map.graph),
-            ) {
-                (Ok(pacman_pixel), Ok(item_pixel)) => {
-                    // Calculate the distance between the two entities's precise pixel positions
-                    let distance = pacman_pixel.distance(item_pixel);
-                    // Calculate the distance at which the two entities will collide
-                    let collision_distance = (pacman_collider.size + item_collider.size) / 2.0;
-
-                    // If the distance between the two entities is less than the collision distance, then the two entities are colliding
-                    if distance < collision_distance {
+            match check_collision(pacman_pos, pacman_collider, item_pos, item_collider, &map) {
+                Ok(colliding) => {
+                    if colliding {
                         events.write(GameEvent::Collision(pacman_entity, item_entity));
                     }
                 }
-                // Either or both of the pixel positions failed to get, so we need to report the error
-                (result_a, result_b) => {
-                    for result in [result_a, result_b] {
-                        if let Err(e) = result {
-                            errors.write(GameError::InvalidState(format!(
-                                "Collision system failed to get pixel positions for entities {:?} and {:?}: {}",
-                                pacman_entity, item_entity, e
-                            )));
-                        }
+                Err(e) => {
+                    errors.write(GameError::InvalidState(format!(
+                        "Collision system failed to check collision between entities {:?} and {:?}: {}",
+                        pacman_entity, item_entity, e
+                    )));
+                }
+            }
+        }
+
+        // Check PACMAN × GHOST collisions
+        for (ghost_entity, ghost_pos, ghost_collider) in ghost_query.iter() {
+            match check_collision(pacman_pos, pacman_collider, ghost_pos, ghost_collider, &map) {
+                Ok(colliding) => {
+                    if colliding {
+                        events.write(GameEvent::Collision(pacman_entity, ghost_entity));
                     }
                 }
+                Err(e) => {
+                    errors.write(GameError::InvalidState(format!(
+                        "Collision system failed to check collision between entities {:?} and {:?}: {}",
+                        pacman_entity, ghost_entity, e
+                    )));
+                }
             }
         }
     }

src/systems/components.rs

@@ -70,6 +70,17 @@ impl EntityType {
             _ => TraversalFlags::empty(), // Static entities don't traverse
         }
     }
+    pub fn score_value(&self) -> Option<u32> {
+        match self {
+            EntityType::Pellet => Some(10),
+            EntityType::PowerPellet => Some(50),
+            _ => None,
+        }
+    }
+
+    pub fn is_collectible(&self) -> bool {
+        matches!(self, EntityType::Pellet | EntityType::PowerPellet)
+    }
 }
 
 /// A component for entities that have a sprite, with a layer for ordering.
@@ -103,6 +114,14 @@ pub struct Collider {
     pub size: f32,
 }
 
+impl Collider {
+    /// Checks if this collider collides with another collider at the given distance.
+    pub fn collides_with(&self, other_size: f32, distance: f32) -> bool {
+        let collision_distance = (self.size + other_size) / 2.0;
+        distance < collision_distance
+    }
+}
+
 /// Marker components for collision filtering optimization
 #[derive(Component)]
 pub struct PacmanCollider;

src/systems/debug.rs

@@ -16,22 +16,13 @@ use sdl2::render::{Canvas, Texture, TextureCreator};
 use sdl2::ttf::Font;
 use sdl2::video::{Window, WindowContext};
 
-#[derive(Resource, Default, Debug, Copy, Clone, PartialEq)]
-pub enum DebugState {
-    #[default]
-    Off,
-    Graph,
-    Collision,
+#[derive(Resource, Default, Debug, Copy, Clone)]
+pub struct DebugState {
+    pub enabled: bool,
 }
 
-impl DebugState {
-    pub fn next(&self) -> Self {
-        match self {
-            DebugState::Off => DebugState::Graph,
-            DebugState::Graph => DebugState::Collision,
-            DebugState::Collision => DebugState::Off,
-        }
-    }
+fn f32_to_u8(value: f32) -> u8 {
+    (value * 255.0) as u8
 }
 
 /// Resource to hold the debug texture for persistent rendering
@@ -110,7 +101,7 @@ pub fn debug_render_system(
     colliders: Query<(&Collider, &Position)>,
     cursor: Res<CursorPosition>,
 ) {
-    if *debug_state == DebugState::Off {
+    if !debug_state.enabled {
         return;
     }
     let scale =
@@ -140,79 +131,86 @@ pub fn debug_render_system(
     // Draw debug info on the high-resolution debug texture
     canvas
         .with_texture_canvas(&mut debug_texture.0, |debug_canvas| {
-            match *debug_state {
-                DebugState::Graph => {
-                    // Find the closest node to the cursor
+            // Find the closest node to the cursor
 
-                    let closest_node = if let Some(cursor_world_pos) = cursor_world_pos {
-                        map.graph
-                            .nodes()
-                            .map(|node| node.position.distance(cursor_world_pos))
-                            .enumerate()
-                            .min_by(|(_, a), (_, b)| a.partial_cmp(b).unwrap_or(Ordering::Less))
-                            .map(|(id, _)| id)
+            let closest_node = if let Some(cursor_world_pos) = cursor_world_pos {
+                map.graph
+                    .nodes()
+                    .map(|node| node.position.distance(cursor_world_pos))
+                    .enumerate()
+                    .min_by(|(_, a), (_, b)| a.partial_cmp(b).unwrap_or(Ordering::Less))
+                    .map(|(id, _)| id)
+            } else {
+                None
+            };
+
+            debug_canvas.set_draw_color(Color::GREEN);
+            for (collider, position) in colliders.iter() {
+                let pos = position.get_pixel_position(&map.graph).unwrap();
+
+                // Transform position and size using common methods
+                let pos = (pos * scale).as_ivec2();
+                let size = (collider.size * scale) as u32;
+
+                let rect = Rect::from_center(Point::from((pos.x, pos.y)), size, size);
+                debug_canvas.draw_rect(rect).unwrap();
+            }
+
+            debug_canvas.set_draw_color(Color {
+                a: f32_to_u8(0.4),
+                ..Color::RED
+            });
+            debug_canvas.set_blend_mode(sdl2::render::BlendMode::Blend);
+            for (start_node, end_node) in map.graph.edges() {
+                let start_node_model = map.graph.get_node(start_node).unwrap();
+                let end_node = map.graph.get_node(end_node.target).unwrap().position;
+
+                // Transform positions using common method
+                let start = transform_position_with_offset(start_node_model.position, scale);
+                let end = transform_position_with_offset(end_node, scale);
+
+                debug_canvas
+                    .draw_line(Point::from((start.x, start.y)), Point::from((end.x, end.y)))
+                    .unwrap();
+            }
+
+            for (id, node) in map.graph.nodes().enumerate() {
+                let pos = node.position;
+
+                // Set color based on whether the node is the closest to the cursor
+                debug_canvas.set_draw_color(Color {
+                    a: f32_to_u8(if Some(id) == closest_node { 0.75 } else { 0.6 }),
+                    ..(if Some(id) == closest_node {
+                        Color::YELLOW
                     } else {
-                        None
-                    };
+                        Color::BLUE
+                    })
+                });
 
-                    debug_canvas.set_draw_color(Color::RED);
-                    for (start_node, end_node) in map.graph.edges() {
-                        let start_node_model = map.graph.get_node(start_node).unwrap();
-                        let end_node = map.graph.get_node(end_node.target).unwrap().position;
+                // Transform position using common method
+                let pos = transform_position_with_offset(pos, scale);
+                let size = (2.0 * scale) as u32;
 
-                        // Transform positions using common method
-                        let start = transform_position_with_offset(start_node_model.position, scale);
-                        let end = transform_position_with_offset(end_node, scale);
+                debug_canvas
+                    .fill_rect(Rect::new(pos.x - (size as i32 / 2), pos.y - (size as i32 / 2), size, size))
+                    .unwrap();
+            }
 
-                        debug_canvas
-                            .draw_line(Point::from((start.x, start.y)), Point::from((end.x, end.y)))
-                            .unwrap();
-                    }
+            // Render node ID if a node is highlighted
+            if let Some(closest_node_id) = closest_node {
+                let node = map.graph.get_node(closest_node_id).unwrap();
+                let pos = transform_position_with_offset(node.position, scale);
 
-                    for (id, node) in map.graph.nodes().enumerate() {
-                        let pos = node.position;
-
-                        // Set color based on whether the node is the closest to the cursor
-                        debug_canvas.set_draw_color(if Some(id) == closest_node {
-                            Color::YELLOW
-                        } else {
-                            Color::BLUE
-                        });
-
-                        // Transform position using common method
-                        let pos = transform_position_with_offset(pos, scale);
-                        let size = (3.0 * scale) as u32;
-
-                        debug_canvas
-                            .fill_rect(Rect::new(pos.x - (size as i32 / 2), pos.y - (size as i32 / 2), size, size))
-                            .unwrap();
-                    }
-
-                    // Render node ID if a node is highlighted
-                    if let Some(closest_node_id) = closest_node {
-                        let node = map.graph.get_node(closest_node_id).unwrap();
-                        let pos = transform_position_with_offset(node.position, scale);
-
-                        let surface = font.render(&closest_node_id.to_string()).blended(Color::WHITE).unwrap();
-                        let texture = texture_creator.create_texture_from_surface(&surface).unwrap();
-                        let dest = Rect::new(pos.x + 10, pos.y - 5, texture.query().width, texture.query().height);
-                        debug_canvas.copy(&texture, None, dest).unwrap();
-                    }
-                }
-                DebugState::Collision => {
-                    debug_canvas.set_draw_color(Color::GREEN);
-                    for (collider, position) in colliders.iter() {
-                        let pos = position.get_pixel_position(&map.graph).unwrap();
-
-                        // Transform position and size using common methods
-                        let pos = (pos * scale).as_ivec2();
-                        let size = (collider.size * scale) as u32;
-
-                        let rect = Rect::from_center(Point::from((pos.x, pos.y)), size, size);
-                        debug_canvas.draw_rect(rect).unwrap();
-                    }
-                }
-                _ => {}
+                let surface = font
+                    .render(&closest_node_id.to_string())
+                    .blended(Color {
+                        a: f32_to_u8(0.4),
+                        ..Color::WHITE
+                    })
+                    .unwrap();
+                let texture = texture_creator.create_texture_from_surface(&surface).unwrap();
+                let dest = Rect::new(pos.x + 10, pos.y - 5, texture.query().width, texture.query().height);
+                debug_canvas.copy(&texture, None, dest).unwrap();
             }
 
             // Render timing information in the top-left corner
@@ -222,4 +220,5 @@ pub fn debug_render_system(
 
     // Draw the debug texture directly onto the main canvas at full resolution
     canvas.copy(&debug_texture.0, None, None).unwrap();
+    canvas.present();
 }

src/systems/input.rs

@@ -28,7 +28,7 @@ pub enum CursorPosition {
 pub struct Bindings {
     key_bindings: HashMap<Keycode, GameCommand>,
     movement_keys: HashSet<Keycode>,
-    last_movement_key: Option<Keycode>,
+    pressed_movement_keys: Vec<Keycode>,
 }
 
 impl Default for Bindings {
@@ -67,11 +67,63 @@ impl Default for Bindings {
         Self {
             key_bindings,
             movement_keys,
-            last_movement_key: None,
+            pressed_movement_keys: Vec::new(),
         }
     }
 }
 
+/// A simplified input event used for deterministic testing and logic reuse
+/// without depending on SDL's event pump.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum SimpleKeyEvent {
+    KeyDown(Keycode),
+    KeyUp(Keycode),
+}
+
+/// Processes a frame's worth of simplified key events and returns the resulting
+/// `GameEvent`s that would be emitted by the input system for that frame.
+///
+/// This mirrors the behavior of `input_system` for keyboard-related logic:
+/// - KeyDown emits the bound command immediately (movement or otherwise)
+/// - Tracks pressed movement keys in order to continue movement on subsequent frames
+/// - KeyUp removes movement keys; if another movement key remains, it resumes
+pub fn process_simple_key_events(bindings: &mut Bindings, frame_events: &[SimpleKeyEvent]) -> Vec<GameEvent> {
+    let mut emitted_events = Vec::new();
+    let mut movement_key_pressed = false;
+
+    for event in frame_events {
+        match *event {
+            SimpleKeyEvent::KeyDown(key) => {
+                if let Some(command) = bindings.key_bindings.get(&key).copied() {
+                    emitted_events.push(GameEvent::Command(command));
+                }
+
+                if bindings.movement_keys.contains(&key) {
+                    movement_key_pressed = true;
+                    if !bindings.pressed_movement_keys.contains(&key) {
+                        bindings.pressed_movement_keys.push(key);
+                    }
+                }
+            }
+            SimpleKeyEvent::KeyUp(key) => {
+                if bindings.movement_keys.contains(&key) {
+                    bindings.pressed_movement_keys.retain(|&k| k != key);
+                }
+            }
+        }
+    }
+
+    if !movement_key_pressed {
+        if let Some(&last_movement_key) = bindings.pressed_movement_keys.last() {
+            if let Some(command) = bindings.key_bindings.get(&last_movement_key).copied() {
+                emitted_events.push(GameEvent::Command(command));
+            }
+        }
+    }
+
+    emitted_events
+}
+
 pub fn input_system(
     delta_time: Res<DeltaTime>,
     mut bindings: ResMut<Bindings>,
@@ -79,11 +131,14 @@ pub fn input_system(
     mut pump: NonSendMut<&'static mut EventPump>,
     mut cursor: ResMut<CursorPosition>,
 ) {
-    let mut movement_key_pressed = false;
     let mut cursor_seen = false;
+    // Collect all events for this frame.
+    let frame_events: Vec<Event> = pump.poll_iter().collect();
 
-    for event in pump.poll_iter() {
-        match event {
+    // Handle non-keyboard events inline and build a simplified keyboard event stream.
+    let mut simple_key_events = Vec::new();
+    for event in &frame_events {
+        match *event {
             Event::Quit { .. } => {
                 writer.write(GameEvent::Command(GameCommand::Exit));
             }
@@ -94,44 +149,28 @@ pub fn input_system(
                 };
                 cursor_seen = true;
             }
-            Event::KeyUp {
-                repeat: false,
-                keycode: Some(key),
-                ..
-            } => {
-                // If the last movement key was released, then forget it.
-                if let Some(last_movement_key) = bindings.last_movement_key {
-                    if last_movement_key == key {
-                        bindings.last_movement_key = None;
-                    }
-                }
-            }
             Event::KeyDown {
                 keycode: Some(key),
                 repeat: false,
                 ..
             } => {
-                let command = bindings.key_bindings.get(&key).copied();
-                if let Some(command) = command {
-                    writer.write(GameEvent::Command(command));
-                }
-
-                if bindings.movement_keys.contains(&key) {
-                    movement_key_pressed = true;
-                    bindings.last_movement_key = Some(key);
-                }
+                simple_key_events.push(SimpleKeyEvent::KeyDown(key));
+            }
+            Event::KeyUp {
+                keycode: Some(key),
+                repeat: false,
+                ..
+            } => {
+                simple_key_events.push(SimpleKeyEvent::KeyUp(key));
             }
             _ => {}
         }
     }
 
-    if let Some(last_movement_key) = bindings.last_movement_key {
-        if !movement_key_pressed {
-            let command = bindings.key_bindings.get(&last_movement_key).copied();
-            if let Some(command) = command {
-                writer.write(GameEvent::Command(command));
-            }
-        }
+    // Delegate keyboard handling to shared logic used by tests and production.
+    let emitted = process_simple_key_events(&mut bindings, &simple_key_events);
+    for event in emitted {
+        writer.write(event);
     }
 
     if let (false, CursorPosition::Some { remaining_time, .. }) = (cursor_seen, &mut *cursor) {

src/systems/item.rs

@@ -8,6 +8,17 @@ use crate::{
     },
 };
 
+/// Determines if a collision between two entity types should be handled by the item system.
+///
+/// Returns `true` if one entity is a player and the other is a collectible item.
+#[allow(dead_code)]
+pub fn is_valid_item_collision(entity1: EntityType, entity2: EntityType) -> bool {
+    match (entity1, entity2) {
+        (EntityType::Player, entity) | (entity, EntityType::Player) => entity.is_collectible(),
+        _ => false,
+    }
+}
+
 pub fn item_system(
     mut commands: Commands,
     mut collision_events: EventReader<GameEvent>,
@@ -29,20 +40,17 @@ pub fn item_system(
 
             // Get the item type and update score
             if let Ok((item_ent, entity_type)) = item_query.get(item_entity) {
-                match entity_type {
-                    EntityType::Pellet => {
-                        score.0 += 10;
+                if let Some(score_value) = entity_type.score_value() {
+                    score.0 += score_value;
+
+                    // Remove the collected item
+                    commands.entity(item_ent).despawn();
+
+                    // Trigger audio if appropriate
+                    if entity_type.is_collectible() {
+                        events.write(AudioEvent::PlayEat);
                     }
-                    EntityType::PowerPellet => {
-                        score.0 += 50;
-                    }
-                    _ => continue,
                 }
-
-                // Remove the collected item
-                commands.entity(item_ent).despawn();
-
-                events.write(AudioEvent::PlayEat);
             }
         }
     }

src/systems/player.rs

@@ -57,7 +57,7 @@ pub fn player_control_system(
                     state.exit = true;
                 }
                 GameCommand::ToggleDebug => {
-                    *debug_state = debug_state.next();
+                    debug_state.enabled = !debug_state.enabled;
                 }
                 GameCommand::MuteAudio => {
                     audio_state.muted = !audio_state.muted;

src/systems/render.rs

@@ -120,4 +120,6 @@ pub fn render_system(
         })
         .err()
         .map(|e| errors.write(TextureError::RenderFailed(e.to_string()).into()));
+
+    canvas.copy(&backbuffer.0, None, None).unwrap();
 }

tests/collision.rs

@@ -0,0 +1,150 @@
+use bevy_ecs::{event::Events, prelude::*, system::RunSystemOnce, world::World};
+
+use pacman::{
+    error::GameError,
+    events::GameEvent,
+    map::builder::Map,
+    systems::{
+        collision::{check_collision, collision_system},
+        components::{Collider, EntityType, Ghost, GhostCollider, ItemCollider, PacmanCollider},
+        movement::Position,
+    },
+};
+
+fn create_test_world() -> World {
+    let mut world = World::new();
+
+    // Add required resources
+    world.insert_resource(Events::<GameEvent>::default());
+    world.insert_resource(Events::<GameError>::default());
+
+    // Add a minimal test map
+    world.insert_resource(create_test_map());
+
+    world
+}
+
+fn create_test_map() -> Map {
+    use pacman::constants::RAW_BOARD;
+    Map::new(RAW_BOARD).expect("Failed to create test map")
+}
+
+fn spawn_test_pacman(world: &mut World) -> Entity {
+    world
+        .spawn((Position::Stopped { node: 0 }, Collider { size: 10.0 }, PacmanCollider))
+        .id()
+}
+
+fn spawn_test_item(world: &mut World) -> Entity {
+    world
+        .spawn((
+            Position::Stopped { node: 0 },
+            Collider { size: 8.0 },
+            ItemCollider,
+            EntityType::Pellet,
+        ))
+        .id()
+}
+
+fn spawn_test_ghost(world: &mut World) -> Entity {
+    world
+        .spawn((
+            Position::Stopped { node: 0 },
+            Collider { size: 12.0 },
+            GhostCollider,
+            Ghost::Blinky,
+            EntityType::Ghost,
+        ))
+        .id()
+}
+
+fn spawn_test_ghost_at_node(world: &mut World, node: usize) -> Entity {
+    world
+        .spawn((
+            Position::Stopped { node },
+            Collider { size: 12.0 },
+            GhostCollider,
+            Ghost::Blinky,
+            EntityType::Ghost,
+        ))
+        .id()
+}
+
+#[test]
+fn test_collider_collision_detection() {
+    let collider1 = Collider { size: 10.0 };
+    let collider2 = Collider { size: 8.0 };
+
+    // Test collision detection
+    assert!(collider1.collides_with(collider2.size, 5.0)); // Should collide (distance < 9.0)
+    assert!(!collider1.collides_with(collider2.size, 15.0)); // Should not collide (distance > 9.0)
+}
+
+#[test]
+fn test_check_collision_helper() {
+    let map = create_test_map();
+    let pos1 = Position::Stopped { node: 0 };
+    let pos2 = Position::Stopped { node: 0 }; // Same position
+    let collider1 = Collider { size: 10.0 };
+    let collider2 = Collider { size: 8.0 };
+
+    // Test collision at same position
+    let result = check_collision(&pos1, &collider1, &pos2, &collider2, &map);
+    assert!(result.is_ok());
+    assert!(result.unwrap()); // Should collide at same position
+
+    // Test collision at different positions
+    let pos3 = Position::Stopped { node: 1 }; // Different position
+    let result = check_collision(&pos1, &collider1, &pos3, &collider2, &map);
+    assert!(result.is_ok());
+    // May or may not collide depending on actual node positions
+}
+
+#[test]
+fn test_collision_system_pacman_item() {
+    let mut world = create_test_world();
+    let _pacman = spawn_test_pacman(&mut world);
+    let _item = spawn_test_item(&mut world);
+
+    // Run collision system - should not panic
+    world
+        .run_system_once(collision_system)
+        .expect("System should run successfully");
+}
+
+#[test]
+fn test_collision_system_pacman_ghost() {
+    let mut world = create_test_world();
+    let _pacman = spawn_test_pacman(&mut world);
+    let _ghost = spawn_test_ghost(&mut world);
+
+    // Run collision system - should not panic
+    world
+        .run_system_once(collision_system)
+        .expect("System should run successfully");
+}
+
+#[test]
+fn test_collision_system_no_collision() {
+    let mut world = create_test_world();
+    let _pacman = spawn_test_pacman(&mut world);
+    let _ghost = spawn_test_ghost_at_node(&mut world, 1); // Different node
+
+    // Run collision system - should not panic
+    world
+        .run_system_once(collision_system)
+        .expect("System should run successfully");
+}
+
+#[test]
+fn test_collision_system_multiple_entities() {
+    let mut world = create_test_world();
+    let _pacman = spawn_test_pacman(&mut world);
+    let _item = spawn_test_item(&mut world);
+    let _ghost = spawn_test_ghost(&mut world);
+
+    // Run collision system - should not panic
+    world
+        .run_system_once(collision_system)
+        .expect("System should run successfully");
+}

tests/events.rs

@@ -1,72 +1,6 @@
 use pacman::events::{GameCommand, GameEvent};
 use pacman::map::direction::Direction;
 
-#[test]
-fn test_game_command_variants() {
-    // Test that all GameCommand variants can be created
-    let commands = vec![
-        GameCommand::Exit,
-        GameCommand::MovePlayer(Direction::Up),
-        GameCommand::MovePlayer(Direction::Down),
-        GameCommand::MovePlayer(Direction::Left),
-        GameCommand::MovePlayer(Direction::Right),
-        GameCommand::ToggleDebug,
-        GameCommand::MuteAudio,
-        GameCommand::ResetLevel,
-        GameCommand::TogglePause,
-    ];
-
-    // Just verify they can be created and compared
-    assert_eq!(commands.len(), 9);
-    assert_eq!(commands[0], GameCommand::Exit);
-    assert_eq!(commands[1], GameCommand::MovePlayer(Direction::Up));
-}
-
-#[test]
-fn test_game_command_equality() {
-    assert_eq!(GameCommand::Exit, GameCommand::Exit);
-    assert_eq!(GameCommand::ToggleDebug, GameCommand::ToggleDebug);
-    assert_eq!(
-        GameCommand::MovePlayer(Direction::Left),
-        GameCommand::MovePlayer(Direction::Left)
-    );
-
-    assert_ne!(GameCommand::Exit, GameCommand::ToggleDebug);
-    assert_ne!(
-        GameCommand::MovePlayer(Direction::Left),
-        GameCommand::MovePlayer(Direction::Right)
-    );
-}
-
-#[test]
-fn test_game_command_copy_clone() {
-    let original = GameCommand::MovePlayer(Direction::Up);
-    let copied = original;
-    let cloned = original.clone();
-
-    assert_eq!(original, copied);
-    assert_eq!(original, cloned);
-    assert_eq!(copied, cloned);
-}
-
-#[test]
-fn test_game_event_variants() {
-    let command_event = GameEvent::Command(GameCommand::Exit);
-    let collision_event = GameEvent::Collision(bevy_ecs::entity::Entity::from_raw(1), bevy_ecs::entity::Entity::from_raw(2));
-
-    // Test that events can be created and compared
-    assert_eq!(command_event, GameEvent::Command(GameCommand::Exit));
-    assert_ne!(command_event, collision_event);
-}
-
-#[test]
-fn test_game_command_to_game_event_conversion() {
-    let command = GameCommand::ToggleDebug;
-    let event: GameEvent = command.into();
-
-    assert_eq!(event, GameEvent::Command(GameCommand::ToggleDebug));
-}
-
 #[test]
 fn test_game_command_to_game_event_conversion_all_variants() {
     let commands = vec![
@@ -83,35 +17,3 @@ fn test_game_command_to_game_event_conversion_all_variants() {
         assert_eq!(event, GameEvent::Command(command));
     }
 }
-
-#[test]
-fn test_move_player_all_directions() {
-    let directions = [Direction::Up, Direction::Down, Direction::Left, Direction::Right];
-
-    for direction in directions {
-        let command = GameCommand::MovePlayer(direction);
-        let event: GameEvent = command.into();
-
-        if let GameEvent::Command(GameCommand::MovePlayer(dir)) = event {
-            assert_eq!(dir, direction);
-        } else {
-            panic!("Expected MovePlayer command with direction {:?}", direction);
-        }
-    }
-}
-
-#[test]
-fn test_game_event_debug_format() {
-    let event = GameEvent::Command(GameCommand::Exit);
-    let debug_str = format!("{:?}", event);
-    assert!(debug_str.contains("Command"));
-    assert!(debug_str.contains("Exit"));
-}
-
-#[test]
-fn test_game_command_debug_format() {
-    let command = GameCommand::MovePlayer(Direction::Left);
-    let debug_str = format!("{:?}", command);
-    assert!(debug_str.contains("MovePlayer"));
-    assert!(debug_str.contains("Left"));
-}

tests/formatting.rs

@@ -119,13 +119,6 @@ fn test_format_timing_display_basic() {
     }
 }
 
-#[test]
-fn test_format_timing_display_empty() {
-    let timing_data = vec![];
-    let formatted = format_timing_display(timing_data);
-    assert!(formatted.is_empty());
-}
-
 #[test]
 fn test_format_timing_display_units() {
     let timing_data = vec![

tests/input.rs

@@ -0,0 +1,38 @@
+use pacman::events::{GameCommand, GameEvent};
+use pacman::map::direction::Direction;
+use pacman::systems::input::{process_simple_key_events, Bindings, SimpleKeyEvent};
+use sdl2::keyboard::Keycode;
+
+#[test]
+fn resumes_previous_direction_when_secondary_key_released() {
+    let mut bindings = Bindings::default();
+
+    // Frame 1: Press W (Up) => emits Move Up
+    let events = process_simple_key_events(&mut bindings, &[SimpleKeyEvent::KeyDown(Keycode::W)]);
+    assert!(events.contains(&GameEvent::Command(GameCommand::MovePlayer(Direction::Up))));
+
+    // Frame 2: Press D (Right) => emits Move Right
+    let events = process_simple_key_events(&mut bindings, &[SimpleKeyEvent::KeyDown(Keycode::D)]);
+    assert!(events.contains(&GameEvent::Command(GameCommand::MovePlayer(Direction::Right))));
+
+    // Frame 3: Release D, no new key this frame => should continue previous key W (Up)
+    let events = process_simple_key_events(&mut bindings, &[SimpleKeyEvent::KeyUp(Keycode::D)]);
+    assert!(events.contains(&GameEvent::Command(GameCommand::MovePlayer(Direction::Up))));
+}
+
+#[test]
+fn holds_last_pressed_key_across_frames_when_no_new_input() {
+    let mut bindings = Bindings::default();
+
+    // Frame 1: Press Left
+    let events = process_simple_key_events(&mut bindings, &[SimpleKeyEvent::KeyDown(Keycode::Left)]);
+    assert!(events.contains(&GameEvent::Command(GameCommand::MovePlayer(Direction::Left))));
+
+    // Frame 2: No input => continues Left
+    let events = process_simple_key_events(&mut bindings, &[]);
+    assert!(events.contains(&GameEvent::Command(GameCommand::MovePlayer(Direction::Left))));
+
+    // Frame 3: Release Left, no input remains => nothing emitted
+    let events = process_simple_key_events(&mut bindings, &[SimpleKeyEvent::KeyUp(Keycode::Left)]);
+    assert!(events.is_empty());
+}

tests/item.rs

@@ -1,159 +1,255 @@
-use pacman::systems::components::EntityType;
+use bevy_ecs::{event::Events, prelude::*, system::RunSystemOnce, world::World};
 
-// Helper functions that extract the core scoring logic from item_system
-// This allows us to test the business rules without ECS complexity
+use pacman::{
+    events::GameEvent,
+    map::builder::Map,
+    systems::{
+        audio::AudioEvent,
+        components::{AudioState, EntityType, ItemCollider, PacmanCollider, ScoreResource},
+        item::{is_valid_item_collision, item_system},
+        movement::Position,
+    },
+};
 
-fn calculate_score_for_item(entity_type: EntityType) -> Option<u32> {
-    match entity_type {
-        EntityType::Pellet => Some(10),
-        EntityType::PowerPellet => Some(50),
-        _ => None,
-    }
-}
-
-fn is_collectible_item(entity_type: EntityType) -> bool {
-    matches!(entity_type, EntityType::Pellet | EntityType::PowerPellet)
-}
-
-fn should_trigger_audio_on_collection(entity_type: EntityType) -> bool {
-    is_collectible_item(entity_type)
+#[test]
+fn test_calculate_score_for_item() {
+    assert!(EntityType::Pellet.score_value() < EntityType::PowerPellet.score_value());
+    assert!(EntityType::Pellet.score_value().is_some());
+    assert!(EntityType::PowerPellet.score_value().is_some());
+    assert!(EntityType::Player.score_value().is_none());
+    assert!(EntityType::Ghost.score_value().is_none());
 }
 
 #[test]
-fn test_pellet_scoring() {
-    assert_eq!(calculate_score_for_item(EntityType::Pellet), Some(10));
+fn test_is_collectible_item() {
+    // Collectible
+    assert!(EntityType::Pellet.is_collectible());
+    assert!(EntityType::PowerPellet.is_collectible());
+
+    // Non-collectible
+    assert!(!EntityType::Player.is_collectible());
+    assert!(!EntityType::Ghost.is_collectible());
 }
 
 #[test]
-fn test_power_pellet_scoring() {
-    assert_eq!(calculate_score_for_item(EntityType::PowerPellet), Some(50));
+fn test_is_valid_item_collision() {
+    // Player-item collisions should be valid
+    assert!(is_valid_item_collision(EntityType::Player, EntityType::Pellet));
+    assert!(is_valid_item_collision(EntityType::Player, EntityType::PowerPellet));
+    assert!(is_valid_item_collision(EntityType::Pellet, EntityType::Player));
+    assert!(is_valid_item_collision(EntityType::PowerPellet, EntityType::Player));
+
+    // Non-player-item collisions should be invalid
+    assert!(!is_valid_item_collision(EntityType::Player, EntityType::Ghost));
+    assert!(!is_valid_item_collision(EntityType::Ghost, EntityType::Pellet));
+    assert!(!is_valid_item_collision(EntityType::Pellet, EntityType::PowerPellet));
+    assert!(!is_valid_item_collision(EntityType::Player, EntityType::Player));
+}
+
+fn create_test_world() -> World {
+    let mut world = World::new();
+
+    // Add required resources
+    world.insert_resource(ScoreResource(0));
+    world.insert_resource(AudioState::default());
+    world.insert_resource(Events::<GameEvent>::default());
+    world.insert_resource(Events::<AudioEvent>::default());
+    world.insert_resource(Events::<pacman::error::GameError>::default());
+
+    // Add a minimal test map
+    world.insert_resource(create_test_map());
+
+    world
+}
+
+fn create_test_map() -> Map {
+    use pacman::constants::RAW_BOARD;
+    Map::new(RAW_BOARD).expect("Failed to create test map")
+}
+
+fn spawn_test_pacman(world: &mut World) -> Entity {
+    world
+        .spawn((Position::Stopped { node: 0 }, EntityType::Player, PacmanCollider))
+        .id()
+}
+
+fn spawn_test_item(world: &mut World, item_type: EntityType) -> Entity {
+    world.spawn((Position::Stopped { node: 1 }, item_type, ItemCollider)).id()
+}
+
+fn send_collision_event(world: &mut World, entity1: Entity, entity2: Entity) {
+    let mut events = world.resource_mut::<Events<GameEvent>>();
+    events.send(GameEvent::Collision(entity1, entity2));
 }
 
 #[test]
-fn test_non_collectible_items_no_score() {
-    assert_eq!(calculate_score_for_item(EntityType::Player), None);
-    assert_eq!(calculate_score_for_item(EntityType::Ghost), None);
+fn test_item_system_pellet_collection() {
+    let mut world = create_test_world();
+    let pacman = spawn_test_pacman(&mut world);
+    let pellet = spawn_test_item(&mut world, EntityType::Pellet);
+
+    // Send collision event
+    send_collision_event(&mut world, pacman, pellet);
+
+    // Run the item system
+    world.run_system_once(item_system).expect("System should run successfully");
+
+    // Check that score was updated
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, 10);
+
+    // Check that the pellet was despawned (query should return empty)
+    let item_count = world
+        .query::<&EntityType>()
+        .iter(&world)
+        .filter(|&entity_type| matches!(entity_type, EntityType::Pellet))
+        .count();
+    assert_eq!(item_count, 0);
 }
 
 #[test]
-fn test_collectible_item_detection() {
-    assert!(is_collectible_item(EntityType::Pellet));
-    assert!(is_collectible_item(EntityType::PowerPellet));
-    assert!(!is_collectible_item(EntityType::Player));
-    assert!(!is_collectible_item(EntityType::Ghost));
+fn test_item_system_power_pellet_collection() {
+    let mut world = create_test_world();
+    let pacman = spawn_test_pacman(&mut world);
+    let power_pellet = spawn_test_item(&mut world, EntityType::PowerPellet);
+
+    send_collision_event(&mut world, pacman, power_pellet);
+
+    world.run_system_once(item_system).expect("System should run successfully");
+
+    // Check that score was updated with power pellet value
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, 50);
+
+    // Check that the power pellet was despawned (query should return empty)
+    let item_count = world
+        .query::<&EntityType>()
+        .iter(&world)
+        .filter(|&entity_type| matches!(entity_type, EntityType::PowerPellet))
+        .count();
+    assert_eq!(item_count, 0);
 }
 
 #[test]
-fn test_audio_trigger_for_collectibles() {
-    assert!(should_trigger_audio_on_collection(EntityType::Pellet));
-    assert!(should_trigger_audio_on_collection(EntityType::PowerPellet));
-    assert!(!should_trigger_audio_on_collection(EntityType::Player));
-    assert!(!should_trigger_audio_on_collection(EntityType::Ghost));
+fn test_item_system_multiple_collections() {
+    let mut world = create_test_world();
+    let pacman = spawn_test_pacman(&mut world);
+    let pellet1 = spawn_test_item(&mut world, EntityType::Pellet);
+    let pellet2 = spawn_test_item(&mut world, EntityType::Pellet);
+    let power_pellet = spawn_test_item(&mut world, EntityType::PowerPellet);
+
+    // Send multiple collision events
+    send_collision_event(&mut world, pacman, pellet1);
+    send_collision_event(&mut world, pacman, pellet2);
+    send_collision_event(&mut world, pacman, power_pellet);
+
+    world.run_system_once(item_system).expect("System should run successfully");
+
+    // Check final score: 2 pellets (20) + 1 power pellet (50) = 70
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, 70);
+
+    // Check that all items were despawned
+    let pellet_count = world
+        .query::<&EntityType>()
+        .iter(&world)
+        .filter(|&entity_type| matches!(entity_type, EntityType::Pellet))
+        .count();
+    let power_pellet_count = world
+        .query::<&EntityType>()
+        .iter(&world)
+        .filter(|&entity_type| matches!(entity_type, EntityType::PowerPellet))
+        .count();
+    assert_eq!(pellet_count, 0);
+    assert_eq!(power_pellet_count, 0);
 }
 
 #[test]
-fn test_score_progression() {
-    // Test that power pellets are worth more than regular pellets
-    let pellet_score = calculate_score_for_item(EntityType::Pellet).unwrap();
-    let power_pellet_score = calculate_score_for_item(EntityType::PowerPellet).unwrap();
+fn test_item_system_ignores_non_item_collisions() {
+    let mut world = create_test_world();
+    let pacman = spawn_test_pacman(&mut world);
 
-    assert!(power_pellet_score > pellet_score);
-    assert_eq!(power_pellet_score / pellet_score, 5); // Power pellets are worth 5x regular pellets
+    // Create a ghost entity (not an item)
+    let ghost = world.spawn((Position::Stopped { node: 2 }, EntityType::Ghost)).id();
+
+    // Initial score
+    let initial_score = world.resource::<ScoreResource>().0;
+
+    // Send collision event between pacman and ghost
+    send_collision_event(&mut world, pacman, ghost);
+
+    world.run_system_once(item_system).expect("System should run successfully");
+
+    // Score should remain unchanged
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, initial_score);
+
+    // Ghost should still exist (not despawned)
+    let ghost_count = world
+        .query::<&EntityType>()
+        .iter(&world)
+        .filter(|&entity_type| matches!(entity_type, EntityType::Ghost))
+        .count();
+    assert_eq!(ghost_count, 1);
 }
 
 #[test]
-fn test_entity_type_variants() {
-    // Test all EntityType variants to ensure they're handled appropriately
-    let all_types = vec![
-        EntityType::Player,
-        EntityType::Ghost,
-        EntityType::Pellet,
-        EntityType::PowerPellet,
-    ];
+fn test_item_system_no_collision_events() {
+    let mut world = create_test_world();
+    let _pacman = spawn_test_pacman(&mut world);
+    let _pellet = spawn_test_item(&mut world, EntityType::Pellet);
 
-    let mut collectible_count = 0;
-    let mut non_collectible_count = 0;
+    let initial_score = world.resource::<ScoreResource>().0;
 
-    for entity_type in all_types {
-        if is_collectible_item(entity_type) {
-            collectible_count += 1;
-            // All collectible items should have a score
-            assert!(calculate_score_for_item(entity_type).is_some());
-        } else {
-            non_collectible_count += 1;
-            // Non-collectible items should not have a score
-            assert!(calculate_score_for_item(entity_type).is_none());
-        }
-    }
+    // Run system without any collision events
+    world.run_system_once(item_system).expect("System should run successfully");
 
-    // Verify we have the expected number of each type
-    assert_eq!(collectible_count, 2); // Pellet and PowerPellet
-    assert_eq!(non_collectible_count, 2); // Player and Ghost
+    // Nothing should change
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, initial_score);
+    let pellet_count = world
+        .query::<&EntityType>()
+        .iter(&world)
+        .filter(|&entity_type| matches!(entity_type, EntityType::Pellet))
+        .count();
+    assert_eq!(pellet_count, 1);
 }
 
 #[test]
-fn test_score_accumulation() {
-    // Test score accumulation logic (simulating multiple collections)
-    let mut total_score = 0u32;
+fn test_item_system_collision_with_missing_entity() {
+    let mut world = create_test_world();
+    let pacman = spawn_test_pacman(&mut world);
 
-    // Collect some items
-    let collected_items = vec![
-        EntityType::Pellet,
-        EntityType::Pellet,
-        EntityType::PowerPellet,
-        EntityType::Pellet,
-        EntityType::PowerPellet,
-    ];
+    // Create a fake entity ID that doesn't exist
+    let fake_entity = Entity::from_raw(999);
 
-    for item in collected_items {
-        if let Some(score) = calculate_score_for_item(item) {
-            total_score += score;
-        }
-    }
+    send_collision_event(&mut world, pacman, fake_entity);
 
-    // Expected: 3 pellets (30) + 2 power pellets (100) = 130
-    assert_eq!(total_score, 130);
+    // System should handle gracefully and not crash
+    world
+        .run_system_once(item_system)
+        .expect("System should handle missing entities gracefully");
+
+    // Score should remain unchanged
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, 0);
 }
 
 #[test]
-fn test_collision_filtering_logic() {
-    // Test the logic for determining valid collision pairs
-    // This mirrors the logic in item_system that checks entity types
+fn test_item_system_preserves_existing_score() {
+    let mut world = create_test_world();
 
-    let test_cases = vec![
-        (EntityType::Player, EntityType::Pellet, true),
-        (EntityType::Player, EntityType::PowerPellet, true),
-        (EntityType::Player, EntityType::Ghost, false), // Not handled by item system
-        (EntityType::Player, EntityType::Player, false), // Not a valid collision
-        (EntityType::Ghost, EntityType::Pellet, false), // Ghosts don't collect items
-        (EntityType::Pellet, EntityType::PowerPellet, false), // Items don't interact
-    ];
+    // Set initial score
+    world.insert_resource(ScoreResource(100));
 
-    for (entity1, entity2, should_be_valid) in test_cases {
-        let is_valid_item_collision = (entity1 == EntityType::Player && is_collectible_item(entity2))
-            || (entity2 == EntityType::Player && is_collectible_item(entity1));
+    let pacman = spawn_test_pacman(&mut world);
+    let pellet = spawn_test_item(&mut world, EntityType::Pellet);
 
-        assert_eq!(
-            is_valid_item_collision, should_be_valid,
-            "Failed for collision between {:?} and {:?}",
-            entity1, entity2
-        );
-    }
-}
-
-#[test]
-fn test_item_collection_side_effects() {
-    // Test that collecting items should trigger the expected side effects
-    let collectible_items = vec![EntityType::Pellet, EntityType::PowerPellet];
-
-    for item in collectible_items {
-        // Should provide score
-        assert!(calculate_score_for_item(item).is_some());
-
-        // Should trigger audio
-        assert!(should_trigger_audio_on_collection(item));
-
-        // Should be marked as collectible
-        assert!(is_collectible_item(item));
-    }
+    send_collision_event(&mut world, pacman, pellet);
+
+    world.run_system_once(item_system).expect("System should run successfully");
+
+    // Score should be initial + pellet value
+    let score = world.resource::<ScoreResource>();
+    assert_eq!(score.0, 110);
 }

tests/player.rs

@@ -21,7 +21,7 @@ fn create_test_world() -> World {
 
     // Add resources
     world.insert_resource(GlobalState { exit: false });
-    world.insert_resource(DebugState::Off);
+    world.insert_resource(DebugState::default());
     world.insert_resource(AudioState::default());
     world.insert_resource(DeltaTime(1.0 / 60.0)); // 60 FPS
     world.insert_resource(Events::<GameEvent>::default());
@@ -222,7 +222,7 @@ fn test_player_control_system_toggle_debug() {
 
     // Check that debug state changed
     let debug_state = world.resource::<DebugState>();
-    assert_eq!(*debug_state, DebugState::Graph);
+    assert_eq!(debug_state.enabled, true);
 }
 
 #[test]
@@ -565,7 +565,7 @@ fn test_player_state_persistence_across_systems() {
     let position = *query.single(&world).expect("Player should exist");
 
     // Check that the state changes persisted individually
-    assert_eq!(debug_state_after_toggle, DebugState::Graph, "Debug state should have toggled");
+    assert_eq!(debug_state_after_toggle.enabled, true, "Debug state should have toggled");
     assert!(audio_muted_after_toggle, "Audio should be muted");
 
     // Player position depends on actual map connectivity