trainBridgeSideV2

turtle.select(1)

function check_inventory()
    local all_empty = false
    local data = turtle.getItemDetail(turtle.getSelectedSlot())

    while (turtle.getItemCount(turtle.getSelectedSlot())) <= 0 or (data.name == "minecraft:magma_block") do
        print('Moving slot')
        if turtle.getSelectedSlot() >= 16 then
            turtle.select(1)
            if all_empty then
                print('All inventory slots empty, shutting down')
                exit()
            end
            all_empty = true
        end
        turtle.select(turtle.getSelectedSlot()+1)
        data = turtle.getItemDetail(turtle.getSelectedSlot())
    end
end

bigSleep = false

side = read()

while true do
    while turtle.detect() do
        sleep(0.5)
        bigSleep = true
    end

    if bigSleep then
        sleep(5.0)
        bigSleep = false
    end

    check_inventory()

    if side == "l" then
        turtle.turnLeft()
        turtle.place()
        turtle.turnRight()
        turtle.forward()
    else
        turtle.turnRight()
        turtle.place()
        turtle.turnLeft()
        turtle.forward()
    end
end