import * as I from 'immutable';

import {Trait} from '@avocado/entity';

export class Damaging extends Trait {

  static defaultParams() {
    return {
      affinities: [],
      lock: 0.1,
      power: 0,
      variance: 0.2,
    };
  }

  initialize() {
    this._affinities = this.params.get('affinities').toJS();
    this._collidingWith = [];
    this._lock = this.params.get('lock');
    this._power = this.params.get('power');
    this._variance = this.params.get('variance');
  }

  get affinities() {
    return this._affinities;
  }

  get lock() {
    return this._lock;
  }

  get power() {
    return this._power;
  }

  get variance() {
    return this._variance;
  }

  listeners() {
    return {

      collisionEnd: (other) => {
        const index = this._collidingWith.indexOf(other);
        this._collidingWith.splice(index, 1);
      },

      collisionStart: (other) => {
        this._collidingWith.push(other);
      },

    };
  }

  tick(elapsed) {
    for (let i = 0; i < this._collidingWith.length; ++i) {
      const entity = this._collidingWith[i];
      if (entity.is('vulnerable')) {
        entity.takeDamageFrom(this.entity);
      }
    }
  }

}