feat: Implement shovel interaction and tile highlighting (#15)

src/features/grid/mod.rs

@@ -1,5 +1,6 @@
 use crate::prelude::*;
 use components::{CropVisual, WaterVisual};
+use std::collections::HashSet;
 
 pub mod components;
 pub mod consts;
@@ -88,7 +89,10 @@ fn cleanup(mut commands: Commands, tile_query: Query<Entity, With<Tile>>) {
 }
 
 fn update_tiles(
-    mut query: Query<(&TileState, &mut AseSlice, &Children), (With<Tile>, Without<CropVisual>)>,
+    mut query: Query<
+        (&TileState, &mut AseSlice, &Children, &Tile),
+        (With<Tile>, Without<CropVisual>),
+    >,
     mut crop_query: Query<
         (&mut Visibility, &mut Transform, &mut AseSlice),
         (With<CropVisual>, Without<WaterVisual>, Without<Tile>),
@@ -99,8 +103,27 @@ fn update_tiles(
     >,
     asset_server: Res<AssetServer>,
     game_config: Res<GameConfig>,
+    inventory: Res<Inventory>,
+    item_stacks: Query<&ItemStack>,
+    grid: Res<Grid>,
+    mut sprite_query: Query<&mut Sprite, With<Tile>>,
 ) {
-    for (state, mut slice, children) in &mut query {
+    let has_shovel = inventory.has_item_type(&item_stacks, ItemType::Shovel);
+
+    let owned_tiles: HashSet<(u32, u32)> = query
+        .iter()
+        .filter_map(|(state, _, _, tile)| {
+            if !matches!(state, TileState::Unclaimed) {
+                Some((tile.x, tile.y))
+            } else {
+                None
+            }
+        })
+        .collect();
+
+    for (state, mut slice, children, tile) in &mut query {
+        let entity = grid.get_tile((tile.x, tile.y)).unwrap(); // Get entity for sprite query
+
         slice.name = match state {
             TileState::Unclaimed => "Unclaimed",
             TileState::Empty => "Empty",
@@ -133,6 +156,34 @@ fn update_tiles(
             _ => Vec3::ONE,
         };
 
+        let mut is_highlighted = false;
+        if has_shovel && matches!(state, TileState::Unclaimed) {
+            // Check if not on edge
+            if tile.x > 0 && tile.x < grid.width - 1 && tile.y > 0 && tile.y < grid.height - 1 {
+                // Check neighbors
+                let neighbors = [
+                    (tile.x + 1, tile.y),
+                    (tile.x.saturating_sub(1), tile.y),
+                    (tile.x, tile.y + 1),
+                    (tile.x, tile.y.saturating_sub(1)),
+                ];
+                for n in neighbors.iter() {
+                    if owned_tiles.contains(n) {
+                        is_highlighted = true;
+                        break;
+                    }
+                }
+            }
+        }
+
+        if let Ok(mut sprite) = sprite_query.get_mut(entity) {
+            if is_highlighted {
+                sprite.color = Color::srgb(0.3, 1.0, 0.3); // Green tint
+            } else {
+                sprite.color = Color::WHITE;
+            }
+        }
+
         for child in children.iter() {
             if let Ok((mut visibility, mut transform, mut sprite)) = crop_query.get_mut(child) {
                 *visibility = match state {

src/features/input/mod.rs

@@ -53,7 +53,13 @@ fn move_click(
     config: Res<GameConfig>,
     phase: Res<CurrentPhase>,
     ui_query: Query<(&ComputedNode, &GlobalTransform), With<Node>>,
+    inventory: Res<Inventory>,
+    item_stacks: Query<&ItemStack>,
 ) {
+    if inventory.has_item_type(&item_stacks, ItemType::Shovel) {
+        return; // Block movement if player has a shovel
+    }
+
     match phase.0 {
         Phase::Focus { .. } => return,
         _ => {}
@@ -78,12 +84,25 @@ fn interact_click(
     config: Res<GameConfig>,
     phase: Res<CurrentPhase>,
     ui_query: Query<(&ComputedNode, &GlobalTransform), With<Node>>,
+    mut commands: Commands,
+    mut inventory: ResMut<Inventory>,
+    mut item_stacks: Query<&mut ItemStack>,
+    grid: Res<Grid>,
+    mut tile_states: Query<&mut TileState>,
 ) {
     match phase.0 {
         Phase::Focus { .. } => return,
         _ => {}
     }
 
+    let has_shovel = inventory.items.iter().any(|&entity| {
+        if let Ok(stack) = item_stacks.get(entity) {
+            stack.item_type == ItemType::Shovel
+        } else {
+            false
+        }
+    });
+
     if mouse_btn.just_pressed(MouseButton::Left) {
         if keys.pressed(KeyCode::ShiftLeft) || keys.pressed(KeyCode::ShiftRight) {
             return;
@@ -92,10 +111,69 @@ fn interact_click(
             return;
         };
 
+        if has_shovel {
+            // Shovel interaction logic
+            let tile_entity = match grid.get_tile((x, y)) {
+                Ok(entity) => entity,
+                Err(_) => return, // Clicked outside grid
+            };
+
+            // Before getting mutable tile_state, check neighbors with immutable borrow
+            let mut has_claimed_neighbor = false;
+            // Check if not on edge first for early exit to avoid checking neighbors outside grid.
+            if x == 0 || x == grid.width - 1 || y == 0 || y == grid.height - 1 {
+                return;
+            }
+
+            let neighbors = [
+                (x + 1, y),
+                (x.saturating_sub(1), y),
+                (x, y + 1),
+                (x, y.saturating_sub(1)),
+            ];
+
+            for (nx, ny) in neighbors.iter() {
+                // Ensure neighbor coordinates are within grid boundaries before attempting to get tile
+                if *nx < grid.width && *ny < grid.height {
+                    if let Ok(neighbor_entity) = grid.get_tile((*nx, *ny)) {
+                        if let Ok(neighbor_state) = tile_states.get(neighbor_entity) {
+                            if !matches!(*neighbor_state, TileState::Unclaimed) {
+                                has_claimed_neighbor = true;
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+
+            if !has_claimed_neighbor {
+                return; // No claimed neighbor, cannot unlock
+            }
+
+            // Now get mutable tile_state, after all immutable neighbor checks are done
+            let mut tile_state = match tile_states.get_mut(tile_entity) {
+                Ok(state) => state,
+                Err(_) => return, // Should not happen
+            };
+
+            // Check if unclaimed AFTER determining neighbor status
+            if !matches!(*tile_state, TileState::Unclaimed) {
+                return;
+            }
+
+            if has_claimed_neighbor {
+                // This check is redundant due to early return above, but kept for clarity
+                // Unlock tile
+                *tile_state = TileState::Empty;
+                inventory.update_item_stack(&mut commands, &mut item_stacks, ItemType::Shovel, -1);
+            }
+            return; // Consume click event, prevent normal tile_click_messages
+        } else {
+            // Normal interaction
             tile_click_messages.write(TileClickMessage { x, y });
         }
+    }
 }
-
 fn debug_click(
     mouse_btn: Res<ButtonInput<MouseButton>>,
     keys: Res<ButtonInput<KeyCode>>,