de-storage.lua

-- APIs

local component = require("component")
local term = require("term")

-- Constants

local name = "draconic_rf_storage"
local debug = false;
local step = 1;

-- Variables

local storageAddress = nil
local proxy = nil
local computer = component.computer

-- Functions

function printd(msg)
    if debug then
        print(msg)
    end
end

function loadStorage()
    for address, componentType in component.list() do
        if componentType == name then
            printd(componentType .. " found at address: " .. address)
            storageAddress = address
        end
    end

    if storageAddress ~= nil then
        proxy = component.proxy(storageAddress)
    end

    if proxy == nil then
        return false
    end

    return true
end

function getEnergy()
    if proxy ~= nil then
        return proxy.getEnergyStored()
    end
    return -1
end

function getMaxEnergy()
    if proxy ~= nil then
        return proxy.getMaxEnergyStored()
    end
    return -1
end

function formatNumber(number)
    local output = string.format("%.3f", number)
    local unitVal = {1000000000000000, 1000000000000, 1000000000, 1000000, 1000}
    local unit = {"P", "T", "G", "M", "k"}
    local units = 5

    local toConvert = math.abs(number)
    local sign = ""

    for i = 1, units do
        if toConvert >= unitVal[i] then
            local x = toConvert / unitVal[i]
            if number < 0 then
                sign = "-"
            end
            output = sign .. string.format("%.3f", x) .. unit[i]
            break
        end
    end

    return output
end

function showEnergy()
    local gpu = term.gpu()
    term.setCursor(1, 1)
    term.clearLine()
    term.setCursor(1, 1)
    gpu.setForeground(0xFFFFFF)
    term.write("Energy: "
        .. formatNumber(getEnergy())
        .. " RF / "
        .. formatNumber(getMaxEnergy())
        .. " RF")
end

function run()
    term.gpu().setResolution(30, 15)

    loadStorage()
    if proxy == nil then
        return 1
    end

    term.clear()
    os.sleep(step)
    while computer.isRunning() do
        showEnergy()
        os.sleep(step)
    end

    return 0
end

-- Main Program

local exitCode = run()