module Modbus
  class PollingService
    class << self
      def start
        return if @thread&.alive?

        @thread = Thread.new do
          puts "[#{Time.current}] Modbus polling service 시작됨"
          last_logged_hour = nil
          loop do
            begin
              now = Time.now
              current_hour = now.hour

              if current_hour != last_logged_hour && now.min == 0
                schedule = Schedule.find_by(hour: current_hour)

                Modbus::Service.new(
                  type:          "write_int16",
                  start_address: 2,
                  end_address:   2,
                  value:         schedule.temperature * 10
                ).execute
                puts "[Schedule] #{current_hour}:00 -> Target temp: #{schedule.temperature}°C"
                last_logged_hour = current_hour
              end
            rescue StandardError => e
              error_message = "[#{Time.current}] 오류: #{e.message}"
              puts error_message
            ensure
              sleep 0.1
            end
          end
        end
      end

      def stop
        if @thread
          @thread.exit
          @thread = nil
          puts "[#{Time.now}] Modbus polling service 중지됨"
        end
      end
    end
  end
end