module Modbus
  class PollingService
    class << self
      def start
        return if $modbus_polling_threads.any?(&:alive?)
        $modbus_polling_threads << start_thread
      end

      def stop
        $modbus_polling_threads.each { |t| t.kill if t.alive? }
        $modbus_polling_threads.clear
        puts "Modbus polling service 중지됨"
      end

      def running?
        $modbus_polling_threads.any?(&:alive?)
      end

      private
      def start_thread
        Thread.new { run_polling_loop }
      end

      def run_polling_loop
        puts "Modbus polling service 시작됨"
        last_logged = nil

        loop do
          begin
            now = Time.now
            current = [ now.hour, now.min ]
            if current != last_logged
              puts "시간 변경 감지됨: #{format('%02d:%02d', current[0], current[1])}"
              schedule = Schedule.find_by(hour: current[0], minute: current[1])
              apply_schedule(schedule) if schedule
              last_logged = current
            end
          rescue => e
            puts  "[#{Time.current}] #{file} 에러: #{e.message}"
          ensure
            sleep 1
          end
        end
      end

      def apply_schedule(schedule)
        if schedule.is_active
          run_script("on_off.rb", "0", "[Schedule] ON")
          run_script(
            "serial.rb",
            (schedule.temperature * 10).to_i.to_s,
            "[Schedule] #{schedule.hour}:#{schedule.minute} → #{schedule.temperature}°C"
          )
        else
          run_script("on_off.rb", "1", "[Schedule] OFF")
        end
      end

      def run_script(file, arg, success_msg)
        path = Rails.root.join(file)
        if system("ruby", path.to_s, arg)
          puts success_msg
        else
          puts "[#{Time.current}] #{file} 실행 실패 (args: #{arg})"
        end
      end
    end
  end
end