ComputerCraft - Treeminer

while turtle.detect() do
    print("Digging the block.")
    turtle.dig()
    if turtle.detectUp() then
        print("Digging up.")
        turtle.digUp()
    end
    if turtle.getFuelLevel() == 0 then
        print("Refueling.")
        turtle.refuel()
    end
    print("Moving up.")
    turtle.up()
    if not turtle.compare() then
        break
    end
end
while not turtle.detectDown() do
    if turtle.getFuelLevel() == 0 then
        print("Refueling.")
        turtle.refuel()
    end
    print("Moving down.")
    turtle.down()
end
print("Finished.")