import {compose} from '@avocado/core';
import {StateProperty, Trait} from '@avocado/entity';
import {Rectangle, Vector} from '@avocado/math';

import {Container} from '../container';
import {hasGraphics} from '../has-graphics';

const decorate = compose(
  StateProperty('isVisible', {
    track: true,
  }),
);

export class Visible extends decorate(Trait) {

  static defaultParams() {
    return {
      trackPosition: true,
    };
  }

  static defaultState() {
    return {
      isVisible: true,
    };
  }

  initialize() {
    if (hasGraphics) {
      this._container = new Container();
      this._container.isVisible = this.entity.isVisible;
    }
    this.trackPosition = this.params.get('trackPosition');
    this._visibleBoundingBox = [0, 0, 0, 0];
  }

  destroy() {
    if (this._container) {
      this._container.destroy();
    }
  }

  get container() {
    return this._container;
  }

  get visibleBoundingBox() {
    if (Rectangle.isNull(this._visibleBoundingBox)) {
      // Collect all bounding boxes.
      const visibleBoundingBoxes = this.entity.invokeHookFlat(
        'visibleBoundingBoxes'
      );
      if (0 === visibleBoundingBoxes.length) {
        return [0, 0, 0, 0];
      }
      let unifiedBoundingBox = [0, 0, 0, 0];
      for (const visibleBoundingBox of visibleBoundingBoxes) {
        unifiedBoundingBox = Rectangle.united(
          unifiedBoundingBox,
          visibleBoundingBox,
        );
      }
      this._visibleBoundingBox = unifiedBoundingBox;
    }
    return this._visibleBoundingBox;
  }

  shouldSynchronizePosition() {
    return this._container && this.trackPosition;
  }

  synchronizePosition() {
    if (!this.entity.is('positioned')) {
      return;
    }
    this.entity.container.position = this.entity.position;
    this.entity.container.zIndex = this.entity.y;
  }

  listeners() {
    const listeners = {

      isVisibleChanged: () => {
        this.entity.container.visible = this.entity.isVisible;
      },

      visibleBoundingBoxesUpdated: () => {
        this._visibleBoundingBox = [0, 0, 0, 0];
      }

    };
    if (this.shouldSynchronizePosition()) {
      listeners.traitAdded = (type) => {
        if (-1 === [
          'visible',
          'positioned',
        ].indexOf(type)) {
          return;
        }
        this.synchronizePosition();
      };
    }
    return listeners;
  }

  tick(elapsed) {
    if (this.shouldSynchronizePosition()) {
      this.synchronizePosition();
    }
  }

}