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

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

export class TileEntity extends decorate(Trait) {

  static defaultState() {
    return {
      tileIndex: 0,
    };
  }

  static type() {
    return 'tile-entity';
  }

  destroy() {
    this.removeTileEntity(this.entity.tileIndex);
  }

  addTileEntity(tileIndex) {
    const layer = this.entity.layer;
    if (!layer) {
      return;
    }
    layer.addTileEntity(this.entity, tileIndex);
  }

  removeTileEntity(tileIndex) {
    const layer = this.entity.layer;
    if (!layer) {
      return;
    }
    layer.removeTileEntity(this.entity, tileIndex);
  }

  setTileIndex() {
    if (!this.entity.layer) {
      return;
    }
    this.entity.tileIndex = this.entity.layer.indexAt(
      Vector.floor(this.entity.tile)
    );
  }

  listeners() {
    return {

      addedToLayer: (layer) => {
        this.setTileIndex();
      },

      removedFromLayer: (layer) => {
        layer.removeTileEntity(this.entity, Vector.floor(this.entity.tile));
      },

      tileChanged: () => {
        this.setTileIndex();
      },

      tileIndexChanged: (oldTileIndex, newTileIndex) => {
        this.removeTileEntity(oldTileIndex);
        this.addTileEntity(newTileIndex);
      },

      traitAdded: (type) => {
        this.setTileIndex();
      },

    };
  }

}