module Ecoportal
  module API
    module Common
      class Client
        module WithRetry
          DELAY_REQUEST_RETRY       = 5
          RETRY_ATTEMPTS            = 5
          HANDLED_CONNECTION_ERRORS = [
            HTTP::ConnectionError,
            IOError
          ].freeze

          include Ecoportal::API::Common::Client::ElasticApmIntegration

          private

          # Helper to ensure unexpected server errors do not bring
          # client scripts immediately down
          # @note it manages limited range of errors, the rest
          #   are not handled.
          def with_retry(
            attempts = retry_attemps,
            delay    = delay_request_retry,
            error_safe: true,
            &block
          )
            response = nil

            attempts.times do |i|
              remaining = attempts - i - 1

              response = with_connection_error_handling(
                remaining,
                error_safe: error_safe,
                callback:   block
              ) do
                block.call
              end

              return response unless some_unexpected_error?(response)

              # handle server errors (5xx) & server bugs (i.e. empty body)
              msg  = "re-attempting (remaining: "
              msg << "#{remaining} attempts out of #{attempts})"
              log(:debug) { msg }

              log_unexpected_server_error(response)

              msg  = "Got server error (#{response.status}): #{response.body}\n"
              msg << "Going to retry (##{i + 1} of #{attempts})"
              log(:debug) { msg }

              sleep(delay) if i < attempts
            end

            response
          end

          def with_connection_error_handling(remaining, callback:, error_safe: true)
            yield
          rescue *handled_connection_errors => err
            raise unless error_safe && remaining.positive?

            msg = "Got #{err.class}: #{err.message}"
            log(:debug) { msg }

            with_retry(remaining, error_safe: error_safe, &callback)
          end

          # Add here other connection errors
          def handled_connection_errors
            self.class::HANDLED_CONNECTION_ERRORS
          end

          def retry_attemps
            self.class::RETRY_ATTEMPTS
          end

          def delay_request_retry
            self.class::DELAY_REQUEST_RETRY
          end
        end
      end
    end
  end
end