'use strict';

var index = require('../../utils/es/index.js');

/**
 * Creates a circle out of an image.
 * @param {function(Error, Jimp)} options (optional) radius, x, y
 * @param {function(Error, Jimp)} cb (optional) a callback for when complete
 * @returns {Jimp} this for chaining of methods
 */
var circle = (() => ({
  circle() {
    let options = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {};
    let cb = arguments.length > 1 ? arguments[1] : undefined;
    if (typeof options === "function") {
      cb = options;
      options = {};
    }
    const radius = options.radius || (this.bitmap.width > this.bitmap.height ? this.bitmap.height : this.bitmap.width) / 2;
    const center = {
      x: typeof options.x === "number" ? options.x : this.bitmap.width / 2,
      y: typeof options.y === "number" ? options.y : this.bitmap.height / 2
    };
    this.scanQuiet(0, 0, this.bitmap.width, this.bitmap.height, function (x, y, idx) {
      const curR = Math.sqrt(Math.pow(x - center.x, 2) + Math.pow(y - center.y, 2));
      if (radius - curR <= 0.0) {
        this.bitmap.data[idx + 3] = 0;
      } else if (radius - curR < 1.0) {
        this.bitmap.data[idx + 3] = 255 * (radius - curR);
      }
    });
    if (index.isNodePattern(cb)) {
      cb.call(this, null, this);
    }
    return this;
  }
}));

module.exports = circle;
