CC Train System - Station

-- Station name should be saved in "station.txt" file!

local TRAIN_COMM_PORT = 101

local modem = peripheral.wrap("left")

if modem.isOpen(TRAIN_COMM_PORT) then
    modem.close(TRAIN_COMM_PORT)
end

modem.open(TRAIN_COMM_PORT)

local function getStationName()
    local sfh = fs.open("station.txt", "r")
    local station_name = sfh.readLine()
    sfh.close()
    return station_name
end

while true do
    local event, modemSide, senderChannel,
    replyChannel, message, senderDistance = os.pullEvent("modem_message")
    local this_station_name = getStationName()
    if message == this_station_name then
        if replyChannel == 102 then -- This station is where the train is coming from
            redstone.setAnalogOutput("right", 10)
            redstone.setAnalogOutput("back", 0)
            redstone.setAnalogOutput("front", 0)
            print("Sending train to target station...")
            sleep(20)
            redstone.setAnalogOutput("right", 0)
        elseif replyChannel == 103 then -- This station is the target, and train is coming from behind the computer
            redstone.setAnalogOutput("right", 0)
            redstone.setAnalogOutput("front", 10)
            print("Receiving train from up the line...")
            sleep(40)
            redstone.setAnalogOutput("right", 10)
            redstone.setAnalogOutput("front", 0)
        elseif replyChannel == 104 then -- This station is the target, and train is coming from in front of the computer
            redstone.setAnalogOutput("right", 0)
            redstone.setAnalogOutput("back", 10)
            print("Receiving train from down the line...")
            sleep(40)
            redstone.setAnalogOutput("right", 10)
            redstone.setAnalogOutput("back", 0)
        end
    elseif not replyChannel == 102 then
        redstone.setAnalogOutput("right", 10)
        redstone.setAnalogOutput("back", 0)
        redstone.setAnalogOutput("front", 0)
        print("This station is not the train's target, letting it pass...")
    end
end