--Core
function modemTimeout(time)
	local timeout = os.startTimer(time)
	while true do
		local ev, p1, p2, p3, p4 = os.pullEvent()
		if ev == 'timer' and p1 == timeout then
			return nil
		elseif ev == 'modem_message' then
			return p1, p2, p3, p4
		end
	end
end

function string:split( inSplitPattern, outResults )
	if not outResults then
		outResults = { }
	end
	local theStart = 1
	local theSplitStart, theSplitEnd = string.find( self, inSplitPattern, theStart )
	while theSplitStart do
		table.insert( outResults, string.sub( self, theStart, theSplitStart-1 ) )
		theStart = theSplitEnd + 1
		theSplitStart, theSplitEnd = string.find( self, inSplitPattern, theStart )
	end
	table.insert( outResults, string.sub( self, theStart ) )
	return outResults
end

local myIP = 20

print("Loading com.grimnet.networking")

print("Connecting to modem")
local modem = peripheral.wrap('right')
modem.open(myIP)

if modem.isOpen(myIP) == true then
	print("Modem Ready")
end

local cmd
while cmd ~= "exit" do
	local raw_cmd = read()
	local cmd_param = raw_cmd:split(" ")
	cmd = cmd_param[0]
	if cmd == "exit" then

	elseif cmd == "ping" then
		local i = read()
		local channel = tonumber(i)
		modem.transmit(channel, myIP, "ping")
		local mS,sC,rC,m = modemTimeout(2)
		if m then
			print("Reply from "..rC.." > "..m)
		else
			print("Message timed out after 2 seconds")
		end
	else
		print("Unknown command: " .. cmd)
	end
end