export const POSITION_GAP = 1000;

export function positionAfter(lastPosition: number | undefined): number {
  return (lastPosition ?? 0) + POSITION_GAP;
}

export function positionBetween(before?: number, after?: number): number {
  if (before === undefined && after === undefined) return POSITION_GAP;
  if (before === undefined) return after! / 2;
  if (after === undefined) return before + POSITION_GAP;
  return (before + after) / 2;
}