import { canvas } from 'unit-circle-convertor';

const convertor = canvas({width: 100, height: 100});

const isInsideUnitCircle = (x, y) => {
  const r = 1;
  const x0 = 0;
  const y0 = 0;
  return Math.sqrt((x - x0) * (x - x0) + (y - y0) * (y - y0)) < r;
};

const mapInsideUnitWheel = (x, y) => {
  if (isInsideUnitCircle(x, y)) return [x, y];
  const angle = Math.atan2(y, x);
  return [Math.cos(angle), Math.sin(angle)];
};

export const map = position => {
  const [a, b] = convertor.toUnit(position.x, position.y);
  const [mappedA, mappedB] = mapInsideUnitWheel(a, b);
  return convertor.toCanvas(mappedA, mappedB);
};