export function svgPathFromPoints(pts: { forEach: (arg0: (p: any) => void) => void }) {
  let out = "";
  pts.forEach(function (p: Number[] | { elements: Number[] }) {
    let x, y;
    if ((p as any).elements) {
      // for vec2
      [x, y] = (p as any).elements;
    } else {
      [x, y] = p as Number[];
    }
    if (out.length === 0) {
      out = "M ";
    } else {
      out += "L ";
    }
    out += "" + x + "," + y + " ";
  });
  return out;
};

export function line(
  ctx: { moveTo: (arg0: any, arg1: any) => void; lineTo: (arg0: any, arg1: any) => any },
  p1: { e: (arg0: number) => any },
  p2: { e: (arg0: number) => any }
) {
  ctx.moveTo(p1.e(1), p1.e(2));
  return ctx.lineTo(p2.e(1), p2.e(2));
};

// http://stackoverflow.com/a/4959890
export function roundRect(
  ctx: {
    beginPath: () => void;
    moveTo: (arg0: any, arg1: any) => void;
    lineTo: (arg0: number, arg1: number) => void;
    arc: (arg0: number, arg1: number, arg2: any, arg3: number, arg4: number, arg5: boolean) => void;
    closePath: () => any;
  },
  sx: number,
  sy: number,
  ex: number,
  ey: number,
  r: number
) {
  const d2r = Math.PI / 180;
  if (ex - sx - 2 * r < 0) {
    r = (ex - sx) / 2;
  } // ensure that the radius isn't too large for x
  if (ey - sy - 2 * r < 0) {
    r = (ey - sy) / 2;
  } // ensure that the radius isn't too large for y
  ctx.beginPath();
  ctx.moveTo(sx + r, sy);
  ctx.lineTo(ex - r, sy);
  ctx.arc(ex - r, sy + r, r, d2r * 270, d2r * 360, false);
  ctx.lineTo(ex, ey - r);
  ctx.arc(ex - r, ey - r, r, d2r * 0, d2r * 90, false);
  ctx.lineTo(sx + r, ey);
  ctx.arc(sx + r, ey - r, r, d2r * 90, d2r * 180, false);
  ctx.lineTo(sx, sy + r);
  ctx.arc(sx + r, sy + r, r, d2r * 180, d2r * 270, false);
  return ctx.closePath();
};