import { clsx, type ClassValue } from "clsx";
import { twMerge } from "tailwind-merge";

export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs));
}

export function formatRelativeTime(iso: string | Date): string {
  const date = typeof iso === "string" ? new Date(iso) : iso;
  const diff = Date.now() - date.getTime();
  const sec = Math.floor(diff / 1000);
  if (sec < 60) return "just now";
  const min = Math.floor(sec / 60);
  if (min < 60) return `${min}m`;
  const hr = Math.floor(min / 60);
  if (hr < 24) return `${hr}h`;
  const day = Math.floor(hr / 24);
  if (day < 7) return `${day}d`;
  return date.toLocaleDateString(undefined, { month: "short", day: "numeric" });
}

export function newId(prefix = ""): string {
  const id =
    typeof crypto !== "undefined" && crypto.randomUUID
      ? crypto.randomUUID()
      : `${Date.now()}-${Math.random().toString(36).slice(2, 10)}`;
  return prefix ? `${prefix}_${id}` : id;
}