advanced 3high

--3 high tunnel program
-- takes length, l, r, m as argument for left, right or middle line
-- fixes walls and ceiling

args = { ... }

length = tonumber(args[1])
side = args[2]

function refill()
    if turtle.getItemCount(1) == 0 then
        for s = 16,2,-1 do
            turtle.select(s)
            turtle.transferTo(1)
        end
        turtle.select(1)
    end
end

function leftWall()
    turtle.turnLeft()
    if not turtle.detect() then
        refill()
        turtle.place()
    end
    turtle.turnRight()
end

function rightWall()
    turtle.turnRight()
    if not turtle.detect() then
        refill()
        turtle.place()
    end
    turtle.turnLeft()
end

function doFloor()
    if not turtle.detectDown() then
        refill()
        turtle.placeDown()
    end
end

function doCeiling()
    if not turtle.detectUp() then
        refill()
        turtle.placeUp()
    end
end

function goUp()
    if turtle.detectUp() then
        turtle.digUp()
    end
    while not turtle.up() do
        sleep(1)
    end
end

function goDown()
    if turtle.detectDown() then
        turtle.digDown()
    end
    while not turtle.down() do
        sleep(1)
    end
end

function goForward()
    if turtle.detect() then
        turtle.dig()
    end
    while not turtle.forward() do
        sleep(1)
    end
end

for i = 1,length do
    --floor
    doFloor()
    for h = 1,3 do
        --walls
        if side == "l" then
            leftWall()
        elseif side == "r" then
            rightWall()
        end
        -- go up
        if h<3 then
            goUp()
        end
    end
    doCeiling()
    for h = 1,2 do
        goDown()
    end
    if i < length then
        goForward()
    end
end