Glass Energy

local bridge = peripheral.wrap("left")
local net = peripheral.wrap("back")

bridge.clear()

local width = 200

local storageUnits = {
   {
         ["id"] = "batbox_0",
         ["name"] = "Main Batbox"
   },
   {
         ["id"] = "batbox_1",
         ["name"] = "Another Batbox"
   }
}

local offset = 0
for key, storageUnit in pairs(storageUnits) do
  pxOffset = offset * 20
  storageUnit["label"] = bridge.addText(4, 4 + pxOffset, storageUnit["name"], 0x000000)
  storageUnit["bar"] = bridge.addBox(4, 14 + pxOffset, 0, 5, 0xCC0000, 0.9)
  storageUnit["bar"].setZIndex(2)
  storageUnit["bg"] = bridge.addBox(4, 14 + pxOffset, width, 5, 0x000000, 0.5)
  offset = offset + 1
end

while true do
  for i=#storageUnits,1,-1 do
        storageUnit = storageUnits[i]
        if net.isPresentRemote(storageUnit["id"]) then
          capacity = net.callRemote(storageUnit["id"], "getCapacity")
          amount = net.callRemote(storageUnit["id"], "getStored")
          storageUnit["bar"].setWidth(width / capacity * amount)
        else
          storageUnit["bar"].delete()
          storageUnit["bg"].delete()
          storageUnit["label"].delete()
          table.remove(storageUnits, i)
        end
  end
  sleep(0.5)
end