require 'amsi/error/bad_request'

module Amsi
  module Validator
    # Ensure there are no errors in the wrapped contents of the body.
    #
    # This validator works on responses that have the following format:
    #
    # <?xml version="1.0" encoding="utf-8"?>
    # <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    #     <soap:Body>
    #         <GetPropertyResidentsResponse xmlns="http://tempuri.org/">
    #             <GetPropertyResidentsResult>&lt;InternetTrafficResponse&gt;&lt;webservice&gt;Leasing&lt;/webservice&gt;&lt;webmethod&gt;GetPropertyResidents&lt;/webmethod&gt;&lt;Error&gt;&lt;ErrorCode&gt;1&lt;/ErrorCode&gt;&lt;ErrorDescription&gt;Validation of user credentials failed.&lt;/ErrorDescription&gt;&lt;/Error&gt;&lt;/InternetTrafficResponse&gt;</GetPropertyResidentsResult>
    #         </GetPropertyResidentsResponse>
    #     </soap:Body>
    # </soap:Envelope>

    class RequestErrors
      # @param response [Hash<String, Object>] the XML response parsed into a
      #   Hash
      def initialize(response)
        @response = response
      end

      # @raise [Amsi::Error::BadRequest] if the response has an error
      #   node in the contents
      def validate!
        return unless error?

        raise Amsi::Error::BadRequest, [error]
      end

      private

      attr_reader :response

      def error_contents
        body = response['soap:Envelope']['soap:Body']
        response_key = body.keys.detect { |key| key !~ /^xmlns/ }
        contents_response = body[response_key]
        result_key = contents_response.keys.grep(/Result$/).first
        escaped_result = contents_response[result_key]
        parsed_result = MultiXml.parse(escaped_result)

        parsed_result['InternetTrafficResponse']
      end

      def error?
        error_contents
      end

      def error
        error = error_contents['Error']

        Struct.new(:message, :error_code).new(
          error['ErrorDescription'],
          error['ErrorCode']
        )
      end
    end
  end
end