excavate code computercraft updated

--this code is for the computercrafted turtles (this mod is used in modpacks like ftb revelations and tekkit)
--to run this program you need to type the name followed by how long how deep and how wide(to the left) you want to make it and if you want it to go up or down (1 = up -1 = down)
--as an example "excavate 10 5 6 1" here I make the hole 10 long 5 deep and 6 wide to the left and go up

local tArgs = {...}

if #tArgs~=4 then

    print("specefie x, y and z and what direction (1 = up -1 = down)")
    local xc, yc, zc, direct = read()

else
    xc = tonumber(tArgs[1])-1
    yc = tonumber(tArgs[2])-1
    zc = tonumber(tArgs[3])-1

    direct = tonumber(tArgs[4])

end


function info()
    print("fuel: "..turtle.getFuelLevel())
    print(" x: "..xc+1)
    print(" y: "..yc+1)
    print(" z: "..zc+1)
    print("program by: wv1106 on reddit and pastebin")
end

function nl()
    if direct==1 then
        turtle.digUp()
        turtle.up()
    elseif direct ==-1 then
        turtle.digDown()
        turtle.down()
    else
        print("1 = up -1 = down")
    end
end

function mine()
    while turtle.detect() do
        turtle.dig()
    end
end

function move()
    while not turtle.forward() do
        if turtle.attack() then
            turtle.suck()
        else
            if turtle.getFuelLevel()<10 then
                turtle.refuel()
            end
        end
    end
end

function lturn()
    turtle.turnLeft()
    mine()
    move()
    turtle.turnLeft()
end

function rturn()
    turtle.turnRight()
    mine()
    move()
    turtle.turnRight()
end

function ehome()
    turtle.turnRight()
    for b=1,zc do
        move()
    end
    turtle.turnRight()
end


function ohome()
    turtle.turnLeft()
    for b=1,zc do
        move()
    end
    turtle.turnLeft()
    for l=1,xc do
        move()
    end
    turtle.turnLeft()
    turtle.turnLeft()
end


function layer()
    for b=1,zc do
        for l=1,xc do
            mine()
            move()
        end
        if (b % 2 == 0) then
            lturn()
        else
            rturn()
        end
    end
    for l=1,xc do
        mine()
        move()
    end
    if (zc % 2 == 0) then
        ohome()
    else
        ehome()
    end
end






--here startts the actual program


info()

for d=1,yc do
    layer()
    nl()
end
layer()
for d=1,yc do
    if direct==1 then

        while not turtle.down() do
            turtle.attackUp()
        end
    elseif direct==-1 then
        while not turtle.up() do
            turtle.attackUp()
        end
    else
        print("error direction not specefied")
    end
end

print("finished!")