/**
 * Normalize protomux-rpc / DHT errors for UI.
 */

/**
 * @param {unknown} err
 * @returns {Error}
 */
export function unwrapError(err) {
  let cur = err
  let depth = 0
  while (cur?.cause && depth < 5) {
    cur = cur.cause
    depth++
  }
  return cur instanceof Error ? cur : new Error(String(cur?.message || cur || 'Unknown error'))
}

/**
 * @param {unknown} err
 * @param {string} [method]
 */
export function normalizeRpcError(err, method) {
  const root = unwrapError(err)
  const e = new Error(root.message || String(err))
  e.code = root.code || err?.code || 'RPC_ERROR'
  e.method = method || root.method || null
  e.cause = err
  return e
}