startup.lua

os.loadAPI("bigfont.lua")

local text = nil

if not fs.exists("text.txt") then
    printError("Must create text.txt")
else
    local textFile = fs.open("text.txt", "r")
    text = {}
    for line in textFile.readLine do
        table.insert(text, line)
    end
    textFile.close()
end

local function draw(name)
    local mon = peripheral.wrap(name)

    mon.setTextScale(1)
    local w, h = mon.getSize()

    mon.setBackgroundColour(colours.green)
    mon.setTextColour(colours.white)
    mon.clear()

    if text then
        bigfont.writeOn(mon, 1, text[2])

        mon.setCursorPos(math.floor((w - (#text[2] * 3)) / 2) - #(text[1]), math.floor(h / 2) + 1)
        mon.write(text[1])

        mon.setCursorPos(math.floor((w - (#text[2] * 3)) / 2) + (#text[2] * 3) + 2, math.floor(h / 2) + 1)
        mon.write(text[3])
    else
        bigfont.writeOn(mon, 1, "New Street", nil, 1)

        local hint1 = "Help name this street!"
        local hint2 = "Send name + coordinates to Yemmel#2747!"

        mon.setCursorPos(math.floor((w - #hint1) / 2) + 1, math.floor(h / 2) + 2)
        mon.write(hint1)

        mon.setCursorPos(math.floor((w - #hint2) / 2) + 1, math.floor(h / 2) + 3)
        mon.write(hint2)
    end
end

peripheral.find("monitor", draw)
while true do
    local _, name = os.pullEvent("peripheral")
    if peripheral.getType(name) == "monitor" then draw(name) end
end