Minecraft - Farm Computer

function floodField()
    print("Flooding field")
    rs.setOutput("right", true) -- flood the field
    os.sleep(10)
    rs.setOutput("right", false)
end

local tickCount = 0
local tickThreshold = 60000 -- 50 minutes
local checkTimer = 60

if fs.exists("tickCount") then
    file = io.open("tickCount", "r")
    tickCount = file:read()
    file:close()
else
    floodField()
end

while true do
    -- start timer
    mainTimer = os.startTimer(checkTimer)

    -- wait for timer to elapse
    event, event1, event2, event3 = os.pullEvent("timer")

    -- add ticks to tick counter
    tickCount = tickCount + (checkTimer * 20)

    -- if tick counter greater than tick threshold then flood
    if tickCount >= tickThreshold then
        floodField()
        tickCount = 0
    end

    file = io.open("tickCount", "w")
    file:write(tickCount)
    file:close()
end