computercraft/rankrefuel

while true do
    if not turtle.getItemDetail().name=="minecraft:bucket" then
        error "Not a bucket!"
    end
    turtle.placeUp()
    if turtle.getItemDetail().name=="minecraft:lava_bucket" then
        turtle.refuel()
    else
        print("Done, fuel level: ", turtle.getFuelLevel())
        break
    end
end