-- definition
local function collect()
    local bFull = true
    local nTotalItems = 0
    
    for n = 1, 16 do
        local nCount = turtle.getItemCount(n)
        if nCount == 0 then
            bFull = false
        end
        nTotalItems = nTotalItems + nCount
    end

    if nTotalItems > collected then
        collected = nTotalItems
        if math.fmod(collected + unloaded, 50) == 0 then
            print("Mined " .. (collected + unloaded) .. " items.")
        end
    end

    if bFull then
        print("No empty slots left.")
        return false
    end
    return true
end

-- export
return { collect = collect }