'use strict';

function safeMessage(error) {
  return String(error?.message || error || 'Unknown error').replace(/https?:\/\/[^\s]+/gi, raw => {
    try { const u = new URL(raw); return u.origin + u.pathname; } catch { return '[source URL]'; }
  }).slice(0, 1500);
}
function classifyFailure(error) {
  const message = safeMessage(error);
  const status = Number(error?.status || /(?:HTTP|returned)\s+(\d{3})/i.exec(message)?.[1]);
  const code = error?.code || error?.cause?.code;
  const failure = (kind, scope, retryable = false) => ({ kind, scope, retryable, message, ...(status ? { httpStatus: status } : {}) });
  if ([401, 403, 429].includes(status) || /captcha|cloudflare|challenge|access.denied|account.ban|paywall|login required/i.test(message)) return failure('access', 'source');
  if (['ENOSPC', 'EROFS', 'EACCES', 'EPERM', 'EIO'].includes(code)) return failure('storage', 'global');
  if (error?.failureKind === 'unavailable' || /No downloadable English|title was not found|HTTP 404/i.test(message)) return failure('unavailable', 'job');
  if (error?.failureKind === 'transient' || status >= 500 || /network|fetch failed|timed? ?out|timeout|socket|connection reset/i.test(message)
    || ['ETIMEDOUT', 'ECONNRESET', 'ENOTFOUND', 'EAI_AGAIN', 'UND_ERR_CONNECT_TIMEOUT'].includes(code)) return failure('transient', 'source', true);
  return failure('adapter', 'job');
}
function progressKey(job) {
  return JSON.stringify([job?.completed || 0, job?.total || 0, job?.current?.sourceId || '', job?.current?.downloadedPages || 0, job?.lastChapter || '']);
}
module.exports = { classifyFailure, safeMessage, progressKey };