--requires
local component = require("component")
local event = require("event")
local modem = component.modem

--port
local chatPort = 312

modem.open(chatPort)

--listen
function doListen(localAddress, remoteAddress, port, distance, message)
    if(port ~= chatPort) then return end
    print(message)
end

--intro / input
io.write("Welcome to GlobalChat!\nEnter a nickname: ")
local nickname = io.read()

io.write("Welcome, "..nickname..", you are now chatting with everyone else running this program(type /quit to exit).\n")

event.listen("modem_message", doListen)

modem.broadcast(chatPort, nickname .." has joined!")
while true do
    local msg = io.read()
    if(msg == "/quit") then
        modem.broadcast(chatPort, nickname .." has quit!")
        break
    end
    modem.broadcast(chatPort, nickname ..": "..msg)
end
event.ignore("modem_message", doListen)