Net 2.0

local event, side, sChannel, rChannel, data, dist
local modems = {}
for index,side in pairs(peripheral.getNames()) do
  if peripheral.getType(side) == "modem" then
    table.insert(modems, peripheral.wrap(side))
  end
end
local SSIDTable = {}
local clientTable = {}
local active
local timeout

local function open(id)
  for index,modem in pairs(modems) do
    modem.open(id)
  end
end
open(os.getComputerID())

local function close(id)
  for index,modem in pairs(modems) do
    modem.close(id)
  end
end

local function metaReceive()
  event, side, sChannel, rChannel, data, dist = os.pullEvent("modem_message")
end

local function _sleep()
  sleep(3)
  timeout = true
end

local function sleepReceive()
  metaReceive()
  timeout = false
end

local function transmit(msg, to)
  for index,modem in pairs(modems) do
    modem.transmit(to, os.getComputerID(), msg)
  end
end

function scan()
  SSIDTable = {}
  open(65435)
  transmit("scanSSID", 65435)
  while true do
    parallel.waitForAny(_sleep, sleepReceive)
    if timeout then
      break
    end
    SSIDTable[data] = rChannel
    close(65435)
  end
end

function getSSIDTable()
  local _table = {}
  for index in pairs(SSIDTable) do
    table.insert(_table, index)
  end
  return _table
end

function connect(ssid, passwd)
  scan()
  open(65435)
  transmit(passwd, SSIDTable[ssid])
  metaReceive()
  if rChannel == SSIDTable[ssid] and data == "success" then
    close(65435)
    active = rChannel
    return true
  else
    close(65435)
    return false
  end
end

function disconnect()
  transmit("disconnect", active)
  active = nil
end

function host(ssid, passwd)
  close(65535)
  open(65435)
  while true do
    metaReceive()
    if data == "scanSSID" then
      transmit(ssid, rChannel)
      print(rChannel .. " requested SSID")
    elseif data == passwd then
      transmit("success", rChannel)
      table.insert(clientTable, rChannel)
      print(rChannel .. " connected")
    elseif data == "disconnect" then
      print("dropped " .. rChannel .. " from clientTable")
      local tmp
      for index,id in pairs(clientTable) do
        if id == rChannel then
          tmp = index
        end
      end
      clientTable[tmp] = nil
    elseif type(data) == "table" then
      for cell,id in pairs(clientTable) do
        if id == data["to"] then
          transmit(data, data["to"])
          print(rChannel .. " relay to " .. data["to"])
          break
        end
      end
    end
  end
end

function send(msg, to)
  local message = {
    from = os.getComputerID(),
    to = to,
    msg = msg
  }
  transmit(message, active)
end

function receive()
  event, side, sChannel, rChannel, data, dist = os.pullEvent("modem_message")
  if sChannel ~= os.getComputerID() then
  else
    return data
  end
  return ""
end