import type { ViewDestination } from "@berry/api/web.ts";

let guard: ((destination: ViewDestination) => boolean | Promise<boolean>) | null = null;

export function guardNavigation(check: NonNullable<typeof guard>) {
  guard = check;
  return () => {
    if (guard === check) guard = null;
  };
}

export function beforeNavigate(route: string): boolean | Promise<boolean> {
  const [tid, extension, ...parts] = route.split("/");
  const decode = (part: string) => {
    try {
      return decodeURIComponent(part);
    } catch {
      return part;
    }
  };
  return guard?.({
    tid: /^[a-z2-7]{13}$/.test(tid) ? tid : null,
    extension: extension ?? null,
    route: parts.map(decode).join("/"),
  }) ?? true;
}