import { AABB } from '@antv/g';
import { Vector2 } from './vector';

type Min = Vector2;
type Max = Vector2;
export type Bounds = [Min, Max];

// There is a certain error in the calculation of text bounds.
const EPSILON = 1e-2;

export function parseAABB(min2: AABB): Bounds {
  const { min, max } = min2;
  return [
    [min[0], min[1]],
    [max[0], max[1]],
  ];
}

/**
 * Whether the `point` in `bounds`.
 * @param point
 * @param bounds
 * @param threshold
 */
export function isInBounds(
  point: Vector2,
  bounds: Bounds,
  threshold = EPSILON,
): boolean {
  const [x, y] = point;
  const [min, max] = bounds;
  return (
    x >= min[0] - threshold &&
    x <= max[0] + threshold &&
    y >= min[1] - threshold &&
    y <= max[1] + threshold
  );
}

/**
 * Whether `b1` is overflow from `b2`.
 * @param b1
 * @param b2
 * @param threshold The threshold to determine whether the bounds is overflowed, default is 0.
 */
export function isOverflow(
  b1: Bounds,
  b2: Bounds,
  threshold = EPSILON,
): boolean {
  const [min, max] = b1;
  return !(isInBounds(min, b2, threshold) && isInBounds(max, b2, threshold));
}

/**
 * Whether `b1` is overlap with `b2`.
 * @param b1
 * @param b2
 * @returns
 */
export function isOverlap(b1: Bounds, b2: Bounds): boolean {
  const [min1, max1] = b1;
  const [min2, max2] = b2;
  return (
    min1[0] < max2[0] &&
    max1[0] > min2[0] &&
    min1[1] < max2[1] &&
    max1[1] > min2[1]
  );
}