Error Handling

{
  "error": "error_code",
  "message": "Human-readable error message",
  "details": { "field": "Additional context" },
  "correlationId": "uuid-for-support-tracking"
}

async function requestWithRetry(fn, maxRetries = 3, baseDelay = 1000) {
  let lastError;

  for (let attempt = 0; attempt < maxRetries; attempt++) {
    try {
      return await fn();
    } catch (error) {
      lastError = error;

      // Don't retry client errors (4xx) except rate limits
      if (error.statusCode >= 400 && error.statusCode < 500
          && error.statusCode !== 429) {
        throw error;
      }

      if (attempt === maxRetries - 1) throw error;

      const delay = Math.min(
        baseDelay * Math.pow(2, attempt) + Math.random() * 1000,
        30000
      );
      await new Promise(resolve => setTimeout(resolve, delay));
    }
  }

  throw lastError;
}

// Simplified offline validation
function validateOffline(cachedLicense) {
  const daysSinceValidation =
    (Date.now() - new Date(cachedLicense.lastValidated)) / (1000 * 60 * 60 * 24);

  if (daysSinceValidation > 7) {
    return { valid: false, reason: 'Please connect to the internet to validate your license.' };
  }

  if (new Date(cachedLicense.validUntil) < new Date()) {
    return { valid: false, reason: 'Your license has expired.' };
  }

  return { valid: true, offline: true, gracePeriodRemaining: Math.ceil(7 - daysSinceValidation) };
}