Coin.ts

import { Container, Graphics } from 'pixi.js';
import * as TWEEN from '@tweenjs/tween.js';
import type RAPIER from '@dimforge/rapier2d-compat';
import { COIN_RADIUS, COLORS } from '../constants';
import type { PhysicsWorld } from '../systems/PhysicsWorld';

/**
 * Sensor pickup. Fixed Rapier body with a sensor ball collider that fires a
 * collision-start event when the player overlaps it. The display object is a
 * tiny Graphics circle that bobs via tween.js.
 */
export class Coin extends Container {
  readonly body: RAPIER.RigidBody;
  readonly collider: RAPIER.Collider;
  private bobTween?: TWEEN.Tween<Container>;

  constructor(
    private physics: PhysicsWorld,
    x: number,
    y: number,