ePages-de/epages-rest-ruby

module Epages
  class Error < StandardError
    attr_reader :code

    # Raised when a 4xx HTTP status code is returned
    ClientError = Class.new(self)

    # HTTP status code 400, 401, 403, 404, 405, 406, 409, 410, 422, 429 respectively
    BadRequest =          Class.new(ClientError)
    Unauthorized =        Class.new(ClientError)
    Forbidden =           Class.new(ClientError)
    NotFound =            Class.new(ClientError)
    MethodNotAllowed =    Class.new(ClientError)
    NotAcceptable =       Class.new(ClientError)
    Conflict =            Class.new(ClientError)
    Gone =                Class.new(ClientError)
    UnprocessableEntity = Class.new(ClientError)
    TooManyRequests =     Class.new(ClientError)

    # Raised when a 5xx HTTP status code is returned
    ServerError = Class.new(self)

    # HTTP status code 500, 502, 503, 504 respectively
    InternalServerError = Class.new(ServerError)
    BadGateway =          Class.new(ServerError)
    ServiceUnavailable =  Class.new(ServerError)
    GatewayTimeout =      Class.new(ServerError)

    ERRORS = {
      400 => Epages::Error::BadRequest,
      401 => Epages::Error::Unauthorized,
      403 => Epages::Error::Forbidden,
      404 => Epages::Error::NotFound,
      405 => Epages::Error::MethodNotAllowed,
      406 => Epages::Error::NotAcceptable,
      409 => Epages::Error::Conflict,
      410 => Epages::Error::Gone,
      422 => Epages::Error::UnprocessableEntity,
      429 => Epages::Error::TooManyRequests,
      500 => Epages::Error::InternalServerError,
      502 => Epages::Error::BadGateway,
      503 => Epages::Error::ServiceUnavailable,
      504 => Epages::Error::GatewayTimeout,
    }

  private

    def parse_error(body)
      if body.nil? || body.empty?
        ['', nil]
      elsif body[:error]
        [body[:error], nil]
      elsif body[:errors]
        extract_message_from_errors(body)
      end
    end

    def extract_message_from_errors(body)
      first = Array(body[:errors]).first
      if first.is_a?(Hash)
        [first[:message].chomp, first[:code]]
      else
        [first.chomp, nil]
      end
    end
  end
end