local path = "/usr/lib/emerald/"

local component = require("component")
local computer = require("computer")
local fs = require("filesystem")
local ser = require("serialization")
local term = require("term")

local emerald = require("emerald")

local modem = component.modem

local bPort = 20

-- INIT FUNCTION --
function init()
  if not fs.exists(path..".eConfig.cfg") then
    local file = io.open(path..".eConfig.cfg", "w")
    file:write("{}")
    file:close()
  end
end

-- READ FUNCTION --
function read()
  local file = io.open(path..".eConfig.cfg", "r")
  local stream = file:read()
  file:close()
  return ser.unserialize(stream)
end

-- WRITE FUNCTION --
function write(data)
  local stream = ser.serialize(data)
  local file = io.open(path..".eConfig.cfg", "w")
  file:write(stream)
  file:close()
end

-- HOSTNAME FUNCTION --
function hostname()
  term.clear()
  print("New hostname:")
  term.write("> ")
  data["hostname"] = io.read()
  write(data)
end

-- GATEWAY FUNCTION --
function gateway()
  term.clear()
  print("Searching...")
  local routerList = emerald.who()
  term.clear()
  print("Select the new gateway:\n")
  for k, v in pairs(routerList) do
    print(k, v)
  end
  term.write("\n> ")
  gatewayAlias = io.read()
  if routerList[gatewayAlias] then
    data["router"] = routerList[gatewayAlias]
    write(data)
  else
    print("Wrong selection.")
    os.sleep(0.5)
  end
end

init()
data = read()

while true do
  term.clear()
  if data["hostname"] then
    print("HOSTNAME: "..data["hostname"])
  else
    print("HOSTNAME: <Not defined>")
  end
  if data["router"] then
    print("GATEWAY: "..data["router"])
  else
    print("GATEWAY: <Not defined>")
  end
  print()
  print([[
1. Change hostname
2. Change gateway
3. Quit
]])
  term.write("> ")
  choice = io.read()

  if choice == "1" then
    hostname()
  elseif choice == "2" then
    gateway()
  elseif choice == "3" then
    break
  end
end