local SLOT_COUNT = 16
local STEPS = 0
function checkFuel()

    turtle.select(1)
    if(turtle.getFuelLevel() < 50) then
        print("Attempting Refuel...")
        for slot = 1, SLOT_COUNT, 1 do
            turtle.select(slot)
            if(turtle.refuel(1)) then
                return true
            end
        end

        return false
    else
        return true
    end
end

function dig()
    for i = 1, 22 do
        while turtle.inspect() ~= "minecraft:bedrock" do
            turtle.dig()
            turtle.digDown()
            turtle.digUp()
            if not turtle.detect() then
                checkFuel()
                turtle.forward()
                STEPS = STEPS + 1
            end
        end
        for n = 1, STEPS do
            turtle.back()
            turtle.turnLeft()
            turtle.forward()
            turtle.turnRight()
        end
        STEPS = 0
    end
end

dig()