Restructuring

src/main/java/se/urmo/game/CollisionChecker.java

@@ -0,0 +1,57 @@
+package se.urmo.game;
+
+
+import java.awt.Point;
+import java.util.Collections;
+import java.util.List;
+
+public class CollisionChecker {
+    private GameMap map;
+
+    public CollisionChecker(GameMap map) {
+        this.map = map;
+    }
+
+    public Point getValidDestination(Direction direction, Point position, int agent_width, int agent_height) {
+        List<Point> list = switch (direction) {
+            case RIGHT -> List.of(
+                    new Point(position.x + agent_width, position.y), // TOPRIGHT
+                    new Point(position.x + agent_width, position.y + agent_height)); // BOTTOMRIGHT
+            case LEFT -> List.of(
+                    position, // TOPLEFT
+                    new Point(position.x, position.y + agent_height)); // BOTTOMLEFT
+            case UP -> List.of(
+                    position, // TOPLEFT
+                    new Point(position.x + agent_width, position.y)); // TOPRIGHT
+            case DOWN -> List.of(
+                    new Point(position.x, position.y + agent_height), // BOTTOMLEFT
+                    new Point(position.x + agent_width, position.y + agent_height)); // BOTTOMRIGHT
+            default -> Collections.EMPTY_LIST;
+        };
+
+        List<Point> list2 = list.stream()
+                .map(p -> normalizePosition(direction, p, agent_width, agent_height))
+                .toList();
+
+        if (map.isPassable(list2)) {
+            return normalizePosition(direction, position, agent_width, agent_height);
+        }
+        return null; // Blocked
+    }
+
+    public Point normalizePosition(Direction dir, Point pos, int agent_width, int agent_height) {
+        int x = pos.x;
+        int y = pos.y;
+        int width = map.getWidth();
+        int height = map.getHeight();
+
+        // tunnel
+        if (x < GameMap.OFFSET_X) x = width - agent_width - GameMap.OFFSET_X;       // right
+        if (x >= (width - GameMap.OFFSET_X)) x = GameMap.OFFSET_X;     // left
+//
+//        if (y < 0) y = height - 1;      // optional vertical wrap
+//        else if (y >= height) y = 0;
+
+        return new Point(x, y);
+    }
+}