class OAuth2::Error

def error_message(response_body, opts = {})
  lines = []
  lines << opts[:error_description] if opts[:error_description]
  error_string = if response_body.respond_to?(:encode) && opts[:error_description].respond_to?(:encoding)
                   script_encoding = opts[:error_description].encoding
                   response_body.encode(script_encoding, invalid: :replace, undef: :replace)
                 else
                   response_body
                 end
  lines << error_string
  lines.join("\n")
end

def initialize(response)
  @response = response
  if response.respond_to?(:parsed)
    if response.parsed.is_a?(Hash)
      @code = response.parsed['error']
      @description = response.parsed['error_description']
    end
  elsif response.is_a?(Hash)
    @code = response['error']
    @description = response['error_description']
  end
  @body = if response.respond_to?(:body)
            response.body
          else
            @response
          end
  message_opts = parse_error_description(@code, @description)
  super(error_message(@body, message_opts))
end

def parse_error_description(code, description)
  return {} unless code || description
  error_description = ''
  error_description += "#{code}: " if code
  error_description += description if description
  {error_description: error_description}
end