'use strict';

// The purpose of this library:
// 1. Have errors consistent with request/promise-core
// 2. Prevent request/promise core from wrapping our errors
// 3. Create descriptive errors.

// There are two differences between these errors and the originals.
// 1. There is a non-enumerable errorType attribute.
// 2. The error constructor is hidden from the stacktrace.

var EOL = require('os').EOL;
var original = require('request-promise-core/errors');
var http = require('http');

var BUG_REPORT = format([
  '### Cloudflare may have changed their technique, or there may be a bug.',
  '### Bug Reports: https://github.com/codemanki/cloudscraper/issues',
  '### Check the detailed exception message that follows for the cause.'
]);

var ERROR_CODES = {
  // Non-standard 5xx server error HTTP status codes
  '522': 'Connection timed out',
  '521': 'Web server is down',
  '520': 'Web server is returning an unknown error',
  '523': 'Origin is unreachable',
  '524': 'A timeout occurred',
  '525': 'SSL handshake failed',
  '526': 'Invalid SSL certificate',
  // Other codes
  '1000': 'DNS points to prohibited IP',
  '1001': 'DNS resolution error',
  '1002': 'Restricted or DNS points to Prohibited IP',
  '1003': 'Access Denied: Direct IP Access Not Allowed',
  '1004': 'Host Not Configured to Serve Web Traffic',
  '1010': 'The owner of this website has banned your access based on your browser\'s signature',
  '1011': 'Access Denied (Hotlinking Denied)',
  '1012': 'Access Denied',
  '1013': 'HTTP hostname and TLS SNI hostname mismatch',
  '1016': 'Origin DNS error'
};

ERROR_CODES[1006] =
    ERROR_CODES[1007] =
        ERROR_CODES[1008] = 'Access Denied: Your IP address has been banned';

var OriginalError = original.RequestError;

var RequestError = create('RequestError', 0);
var CaptchaError = create('CaptchaError', 1);

// errorType 4 is a CloudflareError so this constructor is reused.
var CloudflareError = create('CloudflareError', 2, function (error) {
  if (!isNaN(error.cause)) {
    var description = ERROR_CODES[error.cause] || http.STATUS_CODES[error.cause];
    if (description) {
      error.message = error.cause + ', ' + description;
    }
  }
});

var ParserError = create('ParserError', 3, function (error) {
  error.message = BUG_REPORT + error.message;
});

// The following errors originate from promise-core and it's dependents.
// Give them an errorType for consistency.
original.StatusCodeError.prototype.errorType = 5;
original.TransformError.prototype.errorType = 6;

// This replaces the RequestError for all libraries using request/promise-core
// and prevents silent failure.
Object.defineProperty(original, 'RequestError', {
  configurable: true,
  enumerable: true,
  writable: true,
  value: RequestError
});

// Export our custom errors along with StatusCodeError, etc.
Object.assign(module.exports, original, {
  RequestError: RequestError,
  CaptchaError: CaptchaError,
  ParserError: ParserError,
  CloudflareError: CloudflareError
});

function create(name, errorType, customize) {
  function CustomError(cause, options, response) {

    // This prevents nasty things e.g. `error.cause.error` and
    // is why replacing the original RequestError is necessary.
    if (cause instanceof OriginalError) {
      return cause;
    }

    OriginalError.apply(this, arguments);

    // Change the name to match this constructor
    this.name = name;

    if (typeof customize === 'function') {
      customize(this);
    }

    if (Error.captureStackTrace) { // required for non-V8 environments
      // Provide a proper stack trace that hides this constructor
      Error.captureStackTrace(this, CustomError);
    }
  }

  CustomError.prototype = Object.create(OriginalError.prototype);
  CustomError.prototype.constructor = CustomError;
  // Keeps things stealthy by defining errorType on the prototype.
  // This makes it non-enumerable and safer to add.
  CustomError.prototype.errorType = errorType;

  Object.setPrototypeOf(CustomError, Object.getPrototypeOf(OriginalError));
  Object.defineProperty(CustomError, 'name', {
    configurable: true,
    value: name
  });

  return CustomError;
}

function format(lines) {
  return EOL + lines.join(EOL) + EOL + EOL;
}