/** Next 16 search params arrive as `Promise<Record<string, string | string[] | undefined>>`; these helpers read them safely. */
export type SP = Record<string, string | string[] | undefined>;

export function str(v: string | string[] | undefined): string | undefined {
  if (Array.isArray(v)) return v[0];
  return v === '' ? undefined : v;
}
export function int(v: string | string[] | undefined, fallback: number, min = 1, max = 100000): number {
  const n = Number(str(v));
  if (!Number.isFinite(n)) return fallback;
  return Math.min(max, Math.max(min, Math.floor(n)));
}
export function bool(v: string | string[] | undefined): boolean {
  const s = str(v);
  return s === '1' || s === 'true';
}
/** Current params as a flat string record (for `withParams`). */
export function flat(sp: SP): Record<string, string | undefined> {
  const out: Record<string, string | undefined> = {};
  for (const [k, v] of Object.entries(sp)) out[k] = str(v);
  return out;
}