/**
 * @file rr-error.js
 * @description Centralized error class and assertion logic for Reynolds & Reynolds API calls.
 * Provides consistent handling across all RR modules (customer, repair order, lookups, etc.)
 */

/**
 * Custom Error type for RR API responses
 */
class RrApiError extends Error {
  constructor(message, { reqId, url, apiName, errorData, status, statusText } = {}) {
    super(message);
    this.name = "RrApiError";
    this.reqId = reqId || null;
    this.url = url || null;
    this.apiName = apiName || null;
    this.errorData = errorData || null;
    this.status = status || null;
    this.statusText = statusText || null;
  }
}

/**
 * Assert that a Reynolds & Reynolds response is successful.
 *
 * Expected success structure (based on Rome RR specs):
 * {
 *   "SuccessFlag": true,
 *   "ErrorCode": "0",
 *   "ErrorMessage": "",
 *   "Data": { ... }
 * }
 *
 * Or if SOAP/XML-based:
 * {
 *   "Envelope": {
 *     "Body": {
 *       "Response": {
 *         "SuccessFlag": true,
 *         ...
 *       }
 *     }
 *   }
 * }
 *
 * This helper unwraps and normalizes the response to detect any error cases.
 */
function assertRrOk(data, { apiName = "RR API Call", allowEmpty = false } = {}) {
  if (!data && !allowEmpty) {
    throw new RrApiError(`${apiName} returned no data`, { apiName });
  }

  // Normalize envelope
  const response =
    data?.Envelope?.Body?.Response ||
    data?.Envelope?.Body?.[Object.keys(data.Envelope?.Body || {})[0]] ||
    data?.Response ||
    data;

  // Handle array of errors or error objects
  const errorBlock = response?.Errors || response?.Error || response?.Fault || null;

  // Basic success conditions per RR documentation
  const success =
    response?.SuccessFlag === true ||
    response?.ErrorCode === "0" ||
    response?.ResultCode === "0" ||
    (Array.isArray(errorBlock) && errorBlock.length === 0);

  // If success, return normalized response
  if (success || allowEmpty) {
    return response?.Data || response;
  }

  // Construct contextual error info
  const errorMessage = response?.ErrorMessage || response?.FaultString || response?.Message || "Unknown RR API error";

  throw new RrApiError(`${apiName} failed: ${errorMessage}`, {
    apiName,
    errorData: response,
    status: response?.ErrorCode || response?.ResultCode
  });
}

/**
 * Safely unwrap nested RR API responses for consistency across handlers.
 */
function extractRrResponseData(data) {
  if (!data) return null;

  return (
    data?.Envelope?.Body?.Response?.Data ||
    data?.Envelope?.Body?.[Object.keys(data.Envelope?.Body || {})[0]]?.Data ||
    data?.Data ||
    data
  );
}

module.exports = {
  RrApiError,
  assertRrOk,
  extractRrResponseData
};