fix(navigation): hide guidance near base

src/main/java/games/dmg/spigotbase/BaseNavigationController.java

@@ -10,6 +10,7 @@ final class BaseNavigationController implements Runnable {
     private final Server server;
     private final BaseStateManager stateManager;
     private final PluginSettingsProvider settings;
+    private final BaseBoundsService boundsService;
 
     BaseNavigationController(
         Server server,
@@ -19,6 +20,7 @@ final class BaseNavigationController implements Runnable {
         this.server = server;
         this.stateManager = stateManager;
         this.settings = settings;
+        this.boundsService = new BaseBoundsService(settings);
     }
 
     @Override
@@ -32,7 +34,16 @@ final class BaseNavigationController implements Runnable {
             if (!player.getWorld().getUID().equals(base.worldId())) {
                 continue;
             }
-            Location origin = player.getLocation().clone().add(0.0, 0.15, 0.0);
+            Location playerLocation = player.getLocation();
+            if (!BaseNavigationVisibility.isBeyondBorderBuffer(
+                    base,
+                    boundsService.radius(state),
+                    playerLocation.getX(),
+                    playerLocation.getZ()
+            )) {
+                continue;
+            }
+            Location origin = playerLocation.clone().add(0.0, 0.15, 0.0);
             Vector direction = new Vector(
                 base.x() + 0.5 - origin.getX(),
                 0.0,

src/main/java/games/dmg/spigotbase/BaseNavigationVisibility.java

@@ -0,0 +1,26 @@
+package games.dmg.spigotbase;
+
+final class BaseNavigationVisibility {
+    static final int BORDER_BUFFER = 25;
+
+    private BaseNavigationVisibility() {
+    }
+
+    static boolean isBeyondBorderBuffer(
+        BaseLocation base,
+        int radius,
+        double playerX,
+        double playerZ
+    ) {
+        if (base == null) {
+            throw new IllegalArgumentException("base is required");
+        }
+        if (radius <= 0) {
+            throw new IllegalArgumentException("base radius must be positive");
+        }
+        double deltaX = playerX - (base.x() + 0.5);
+        double deltaZ = playerZ - (base.z() + 0.5);
+        double minimumDistance = radius + BORDER_BUFFER;
+        return deltaX * deltaX + deltaZ * deltaZ > minimumDistance * minimumDistance;
+    }
+}