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

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

export function generateUUID() {
  if (typeof globalThis.crypto?.randomUUID === "function") {
    return globalThis.crypto.randomUUID();
  }

  const bytes = new Uint8Array(16);
  if (typeof globalThis.crypto?.getRandomValues === "function") {
    globalThis.crypto.getRandomValues(bytes);
  } else {
    for (let i = 0; i < bytes.length; i += 1) {
      bytes[i] = Math.floor(Math.random() * 256);
    }
  }

  bytes[6] = (bytes[6] & 0x0f) | 0x40;
  bytes[8] = (bytes[8] & 0x3f) | 0x80;

  const hex = Array.from(bytes, (byte) => byte.toString(16).padStart(2, "0"));
  return [
    hex.slice(0, 4).join(""),
    hex.slice(4, 6).join(""),
    hex.slice(6, 8).join(""),
    hex.slice(8, 10).join(""),
    hex.slice(10, 16).join(""),
  ].join("-");
}

export function formatDateTime(value?: string | null) {
  if (!value) {
    return "";
  }
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) {
    return value;
  }
  const pad = (num: number) => String(num).padStart(2, "0");
  return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())} ${pad(date.getHours())}:${pad(date.getMinutes())}:${pad(date.getSeconds())}`;
}