(function () {
  /*---------------------
  ------- IMPORT --------
  ----------------------*/
  var { PIXI } = window.flatworld_libraries;
  var getHexagonPoints = window.flatworld.extensions.hexagons.utils.getHexagonPoints;

  /*-----------------------
  ---------- API ----------
  -----------------------*/
  window.flatworld.extensions.hexagons.utils.createHexagon = createHexagon;
  window.flatworld.extensions.hexagons.utils.createVisibleHexagon = createVisibleHexagon;

  /*-----------------------
  --------- PUBLIC --------
  -----------------------*/
  /**
   * This manages some utility functionalities for creating hexagons
   *
   * @class extensions.hexagons.utils
   */
  /**
   * Credits belong to: https://github.com/alforno-productions/HexPixiJs/blob/master/lib/hexPixi.js
   * Creates a hex shaped polygon that is used for the hex's hit area.
   *
   * @private
   * @static
   * @method createHexagon
   * @param {Number} radius           Radius of the hexagon
   * @param {Object} {}               *OPTIONAL*
   * @param {Object} {}.orientation   Is the heaxgon grid horizontal or vertical. Default: 'horizontal"
   * @return {PIXI.Polygon}           Hexagon shaped PIXI.Polygon object. That houses the hexagons corner points.
   */
  function createHexagon(radius, { orientation = 'horizontal' } = {}) {
    var points = [];

    if (orientation !== 'horizontal') {
      throw new Error('Nothing else than horizontal supported so far!');
    }
    points = coordsToPixiPoints(radius);

    return new PIXI.Polygon(points);
  }
  /**
   * @private
   * @static
   * @method createVisibleHexagon
   * @method createVisibleHexagon
   * @param {Number} radius       Radius of the hexagon
   * @param {Object} options      Options, such as:
   *                              color: The fill color of the hexagon
   *                              isFlatTop (Boolean), is the heaxgon flat-topped
   * @return {PIXI.Graphics}      Graphics object that is shaped as hexagon, based on given radius and options.
   */
  function createVisibleHexagon(radius, { color = 0xFF0000, isFlatTop = false } = {}) {
    var graphics = new PIXI.Graphics();
    var points = coordsToPixiPoints(radius, isFlatTop);

    graphics.beginFill(color, 1);
    graphics.drawPolygon(points, isFlatTop);
    graphics.endFill();

    return graphics;
  }

  /*-----------------------
  --------- PRIVATE -------
  -----------------------*/
  /**
   * Converts Array of x- and y-coordinates to new PIXI.Point coordinates
   *
   * @private
   * @static
   * @method coordsToPixiPoints
   * @method coordsToPixiPoints
   * @param  {Number} radius        Hexagons radius
   * @return {Array}                Array of PIXI.Point coordinates
   */
  function coordsToPixiPoints(radius) {
    return getHexagonPoints({ radius }).map(function (point) {
      return new PIXI.Point(point.x, point.y);
    });
  }
})();