pp

local nowKey
local function keyCheck()
    while true do
        local event, key, isHeld = os.pullEvent("key")
        nowKey = keys.getName(key)
    end
end

local function keyMap(kvalue)
    if(kvalue == "w") then
        turtle.forward()
    elseif (kvalue == "s") then
        turtle.back()
    elseif (kvalue == "a") then
        turtle.turnLeft()
    elseif (kvalue == "d") then
        turtle.turnRight()
    elseif (kvalue == "leftShift") then
        turtle.down()
    elseif (kvalue == "space") then
        turtle.up()
    end
end

local function moveloop()
while 1 do
    if(nowKey ~= nil) then
        keyMap(nowKey)
        nowKey = nil
    end
    os.sleep(1)
end
end

if(arg[1] == nil) then
    parallel.waitForAll(moveloop,keyCheck)
    return
end
print("start work!")
local emptyFlag =false
local bkslot = 2

local function turtleSelfCheck()
    -- check fuel
    if(turtle.getFuelLevel() < 100) then
        turtle.select(1)
        turtle.refuel(1)
    end
    -- check space
    turtle.select(bkslot)
    if(emptyFlag == false) then
        while (turtle.getItemCount() == 0) do
            bkslot = bkslot + 1
            if(turtle.getItemCount(2) ~= 0) then
                bkslot = 2
                break
            end
            if(bkslot > 16) then
                os.shutdown()
            end
            turtle.select(bkslot)
        end
    end

end


local count = tonumber(arg[1])
local orient = arg[2]
while (count > 0) do

    turtleSelfCheck()
    -- place
    if(orient == "u") then
        turtle.up()
        turtle.forward()
        turtle.placeDown()
    elseif (orient == "d") then
        turtle.forward()
        turtle.down()
        turtle.placeDown()
    else
        break
    end
    count = count - 1
end