startup.lua

rednet.open "top"

local inventories = {}
for _, n in pairs(peripheral.getNames()) do
    local p = peripheral.wrap(n)
    if
        string.find(n, "chest") or
        string.find(n, "shulker") then
        inventories[n] = p
    end
end

local nameCache = {}

function cache(item, chest, slot)
    local idx = item.name .. ":" .. item.damage

    if nameCache[idx] then
        return nameCache[idx]
    else
        nameCache[idx] = chest.getItemMeta(slot).displayName
    end
end

local index = {}
function updateIndexFor(name)
    local inv = inventories[name]
    local data = inv.list()

    for slot, item in pairs(data) do
        data[slot].displayName = cache(item, inv, slot)
        os.queueEvent "dummy"
        os.pullEvent "dummy"
    end

    index[name] = data
end

function updateIndex()
    while true do
        for n in pairs(inventories) do
            updateIndexFor(n)
            sleep(0.1)
        end
    end
end

function find(predicate)
    for name, items in pairs(index) do
        for slot, item in pairs(items) do
            if predicate(item) then
                return name, slot, item
            end
        end
    end
end

function findSpace()
    for name, items in pairs(index) do
        if #items < inventories[name].size() then
            return name
        end
    end
end

function processRequest(msg)
    print(textutils.serialise(msg))

    if msg.cmd == "find" then
        return {find(function(item)
            return
                (not msg.meta or item.damage == msg.meta) and
                (not msg.name or item.name == msg.name) and
                (not msg.dname or string.find(item.displayName, msg.dname))
        end)}
    elseif msg.cmd == "space" then
        return findSpace()
    elseif msg.cmd == "list" then
        return index
    elseif msg.cmd == "name" then
        msg.meta = msg.meta or 0
        return msg.name and msg.meta and nameCache[msg.name .. ":" .. msg.meta]
    end
end

function processRequests()
    while true do
        local id, msg = rednet.receive "mw"
        if msg and msg.cmd then
            local ok, r = pcall(processRequest, msg)
            print(textutils.serialise(r))
            rednet.send(id, r, "mw")
        end
    end
end

parallel.waitForAll(updateIndex, processRequests)