/**
 * Client-side unique id for list keys / draft rows / visitor ids.
 * Prefer Web Crypto when available; some non-secure contexts (e.g. http://LAN-IP)
 * expose `crypto` without `randomUUID`.
 */
export function createClientId(): string {
  const webCrypto = globalThis.crypto

  if (typeof webCrypto?.randomUUID === 'function') {
    return webCrypto.randomUUID()
  }

  if (typeof webCrypto?.getRandomValues === 'function') {
    const bytes = new Uint8Array(16)

    webCrypto.getRandomValues(bytes)
    // نسخه ۴ UUID
    bytes[6] = (bytes[6] & 0x0f) | 0x40
    bytes[8] = (bytes[8] & 0x3f) | 0x80

    const hex = Array.from(bytes, (byte) => byte.toString(16).padStart(2, '0')).join('')

    return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`
  }

  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (char) => {
    const nibble = (Math.random() * 16) | 0
    const value = char === 'x' ? nibble : (nibble & 0x3) | 0x8

    return value.toString(16)
  })
}