digger

function hasAnyTag(str, tags)
    for _, tag in ipairs(tags) do
        if string.find(str, tag) ~= nil then
            return true
        end
    end
    return false
end

function isBlock(itemName)
    local blockTags = {"cobblestone"}
    return hasAnyTag(itemName, blockTags)
end

function isValuable(itemName)
    return hasAnyTag(itemName, {"diamond", "gold", "emerald", "iron"})
end
function setToNotValuableBlockSlot()
    for i = 1, 16 do
        local itemName = turtle.getItemDetail(i).name
        if not isValuable(itemName) and isBlock(itemName) then
            turtle.select(i)
            return true
        end
    end
    return false
end

function moveInSpiral(targetSize, toOutside, callback)
    local function moveForward(n)
        for _ = 1, n do
            turtle.forward()
            callback()
        end
    end

    moveForward(targetSize)
    turtle.turnLeft()
    for i = targetSize - 1, 1, -1 do
        for _ = 1, 2 do
            moveForward(i)
            turtle.turnLeft()
        end
    end
end

function moveZig(forward, left, callback)
    local function moveForward(n)
        for _ = 1, n do
            callback()
            turtle.forward()
        end
    end
    callback()
    for i = 1, left-1 do
        local even = i % 2 == 0
        moveForward(forward-1)
        if not even then
            turtle.turnLeft()
        else
            turtle.turnRight()
        end
        moveForward(1)
        if not even then
            turtle.turnLeft()
        else
            turtle.turnRight()
        end
    end
    moveForward(forward-1)

end

function repeatFunc(callback, n)
    for i = 1, n do
        callback()
    end
end

function move(direction, n)
    local moveFunc
    if "forward" then
        moveFunc = turtle.forward
    elseif "down" then
        moveFunc = turtle.down
    elseif "up" then
        moveFunc = turtle.up
    end

    for i = 1, n do
        moveFunc()
    end
end

local width = tonumber(arg[1]) or 4
local length = tonumber(arg[2]) or 4
local height = tonumber(arg[3]) or 4

if height < 2 then
    error("2 is height minimum")
end
if turtle.inspectUp() then
    turtle.digUp()
end
turtle.up()
for i = 1, height - 1 do
    local width = tonumber(width)
    moveZig(tonumber(length), width, function()
        if turtle.inspect() then
            while turtle.dig() do end
        end
        turtle.digDown()
    end)
    if width % 2 == 0 then
        turtle.turnLeft()
    else
        turtle.turnLeft()
        turtle.turnLeft()
    end
    if i == 1 then
        turtle.digDown()
    end
    local isLast = i == height - 1
    if not isLast then
        if turtle.inspectUp() then
            turtle.digUp()
        end
        turtle.up()
    else
        repeatFunc(turtle.down, height)
        repeatFunc(turtle.forward, length)
        turtle.turnLeft()
        repeatFunc(turtle.forward, width)
        turtle.turnLeft()
    end
end