[CC] Pet Turtle

function forward(n)
  for i=1,n do
        while not turtle.detectDown() do
          turtle.down()
        end
        if not turtle.forward() then
          if not turtle.detectDown() then
                turtle.down()
          end
          if not turtle.up() then
                break
          end
          if not turtle.forward() then
                turtle.down()
                break
          end
        end
        if not turtle.detectDown() then
          turtle.down()
        end
  end
end
function right(n)
  turtle.turnRight()
  forward(n)
end
function left(n)
  turtle.turnLeft()
  forward(n)
end
function back(n)
  turtle.turnRight()
  turtle.turnRight()
  forward(n)
end
while true do
  dir=math.random(1,4)
  n=math.random(1,4)
  if dir==1 then
        forward(n)
  end
  if dir==2 then
        right(n)
  end
  if dir==3 then
        back(n)
  end
  if dir==4 then
        left(n)
  end
  if turtle.getFuelLevel()<100 then
        turtle.refuel()
  end
  if not (math.random(1,4)==1) then
        sleep(math.random(1,5))
  end
end