ndisk_space.lua

-- ndisk_space.lua
-- Simple standalone tool to check NDisk storage space
-- No config files needed - just run it

local modem = peripheral.find("modem")
if not modem then error("No modem found") end

modem.open(5) -- NDisk channel

-- Load NDisk secret for authentication
local NDISK_SECRET = nil
if fs.exists(".ndisk_secret") then
    local f = fs.open(".ndisk_secret", "r")
    NDISK_SECRET = f.readAll()
    f.close()
end

print("NDisk Space Monitor")
print("===================")
print("Discovering storage nodes...")

-- Broadcast discovery
modem.transmit(5, 5, {type = "discovery", secret = NDISK_SECRET})

local nodes = {}
local timer = os.startTimer(3)

while true do
    local event, p1, p2, p3, p4 = os.pullEvent()
    if event == "modem_message" and type(p4) == "table" and p4.type == "discovery_response" then
        nodes[p4.id] = true
    elseif event == "timer" and p1 == timer then
        break
    end
end

local nodeList = {}
for id, _ in pairs(nodes) do
    table.insert(nodeList, id)
end

if #nodeList == 0 then
    print("No storage nodes found!")
    return
end

print("Found " .. #nodeList .. " nodes")
print("")

-- Query each node for space
local totalFree = 0
local totalUsed = 0

for _, nodeId in ipairs(nodeList) do
    local requestId = os.epoch("utc")
    modem.transmit(5, 5, {
        targetNode = nodeId,
        action = "getSpace",
        id = requestId,
        secret = NDISK_SECRET
    })

    local spaceTimer = os.startTimer(2)
    while true do
        local event, p1, p2, p3, p4 = os.pullEvent()
        if event == "modem_message" and type(p4) == "table" and p4.id == requestId then
            if p4.response and p4.response.success then
                local free = p4.response.space or 0
                totalFree = totalFree + free
                print("Node " .. nodeId .. ": " .. math.floor(free/1024) .. " KB free")
            else
                print("Node " .. nodeId .. ": Error")
            end
            break
        elseif event == "timer" and p1 == spaceTimer then
            print("Node " .. nodeId .. ": Timeout")
            break
        end
    end
end

print("")
print("===================")
print("Total Free: " .. math.floor(totalFree/1024) .. " KB")
print("           (" .. #nodeList .. " nodes)")