import type { PropertyBag } from '../model/Properties';
import { defaultsFor } from './PropertySchema';

/** Axis-aligned rectangle in world units. */
export interface WorldRect {
  left: number;
  top: number;
  right: number;
  bottom: number;
}

/**
 * Size of the world region a camera shows, in world units: its view size divided by its
 * zoom. This is the frame drawn in edit mode and the only region rendered in play mode.
 */
export function cameraFrame(props: PropertyBag): { w: number; h: number } {
  const d = defaultsFor('camera');
  const zoom = Math.max(0.01, Number(props.zoom ?? d.zoom));
  return { w: Number(props.width ?? d.width) / zoom, h: Number(props.height ?? d.height) / zoom };
}

export function rectAround(cx: number, cy: number, w: number, h: number): WorldRect {
  return { left: cx - w / 2, top: cy - h / 2, right: cx + w / 2, bottom: cy + h / 2 };
}

export function rectsIntersect(a: WorldRect, b: WorldRect): boolean {
  return a.left < b.right && a.right > b.left && a.top < b.bottom && a.bottom > b.top;
}