import * as I from 'immutable';

import {compose} from '@avocado/core';
import {Rectangle, Vector} from '@avocado/math';
import {EventEmitter} from '@avocado/mixins';

const decorate = compose(
  EventEmitter,
  Vector.Mixin('position', 'x', 'y', {
    default: [0, 0],
    track: true,
  }),
);

class BodyBase {

  constructor(shape) {
    this.force = [0, 0];
    this.impulse = [0, 0];
    this.contacts = I.Set();
    this.shape = shape;
  }

  get aabb() {
    return Rectangle.translated(this.shape.aabb, this.position);
  }

  applyForce(vector) {
    this.force = Vector.add(this.force, vector);
  }

  applyImpulse(vector) {
    this.impulse = Vector.add(this.impulse, vector);
  }

}

export class Body extends decorate(BodyBase) {}