/**
 * Simple slugify helper (Vietnamese-friendly) to match CMS behavior:
 * - lowercased
 * - diacritics removed (NFD)
 * - "đ" -> "d"
 * - strict: keep [a-z0-9 -] only, then collapse spaces/hyphens
 */
export function toSlug(input: string): string {
  return (input || "")
    .trim()
    .toLowerCase()
    .normalize("NFD")
    .replace(/[\u0300-\u036f]/g, "")
    .replace(/đ/g, "d")
    .replace(/[^a-z0-9\s-]/g, "")
    .replace(/\s+/g, "-")
    .replace(/-+/g, "-")
    .replace(/^-|-$/g, "");
}