Gui

function center(str, ypos)
    local w,h = term.getSize()
    term.setCursorPos(w/2 - #str/2, ypos)
    term.write(str)
end

function left(str, ypos)
    local w,h = term.getSize()
    term.setCursorPos(w - #str + 1, ypos)
    term.write(str)
end

function right(str, ypos)
    local w,h = term.getSize()
    term.setCursorPos(1, ypos)
    term.write(str)
end


function menu()
term.clear()
center("---------------------------------------", 1)
center("THE CIRCLEJERK", 2)
center("---------------------------------------", 3)
center("[S]  START", 7)
center("[F]  REFUEL", 8)
right("[Fuel: "..turtle.getFuelLevel().."]", 13)
left("by Orginalet", 13)

while true do
    local sEvent, param = os.pullEvent("key")
        if sEvent == "key" then
            if param == 31 then
                term.clear()
                center("Please move away from", 7)
                center("the turtle.", 8)
                os.sleep(5)
                term.clear()
                center("Starting to build.", 7)
                os.sleep(1)
                term.clear()
                shell.run("circle.lua")
                break
            elseif param == 33 then
                term.clear()
                center("Please put fuel in", 7)
                center("top left slot.", 8)
                center("(5)", 9)
                os.sleep(1)
                center("(4)", 9)
                os.sleep(1)
                center("(3)", 9)
                os.sleep(1)
                center("(2)", 9)
                os.sleep(1)
                center("(1)", 9)
                os.sleep(.5)
                turtle.refuel(64)
                term.clear()
                center("Fuel level is now: "..turtle.getFuelLevel(), 7)
                center("Required: 3019.", 8)
                os.sleep(3)
                term.clear()
                menu()
                break
            end
        end
end
end

menu()