MCRegisterServer

local version = "1.15"  --change this to allow for an update (3 chars only)
local filename = "MCAuth"  --change this to the name of the file holding this program
local paste = "nGjQhbbZ"  --change this to the pastebin entry code

local function update()
        local url = "http://pastebin.com/raw/"..paste
        local temp = http.get(url)
        local ver = string.sub(temp.readLine(), 18, 21)

        if ver ~= version then
                fs.delete(filename)
                shell.run("pastebin get "..paste.." "..filename)
                shell.run(filename)
                return true
        end

        return false

end

--start
if update() then
    error()
end
shell.run("clear")

local function insSend()

end

local function split(str, pat)
   local t = {}  -- NOTE: use {n = 0} in Lua-5.0
   local fpat = "(.-)" .. pat
   local last_end = 1
   local s, e, cap = str:find(fpat, 1)
   while s do
      if s ~= 1 or cap ~= "" then
     table.insert(t,cap)
      end
      last_end = e+1
      s, e, cap = str:find(fpat, last_end)
   end
   if last_end <= #str then
      cap = str:sub(last_end)
      table.insert(t, cap)
   end
   return t
end

rednet.open("top")

--check for directory
if not fs.exists("USERS") then
    fs.makeDir("USERS")
end

--host protocol for id
rednet.host("MCAuth","AuthenticationServer")

while true do
    local event, p1, p2, p3 = os.pullEvent()

    if event == "rednet_message" and type(p2) == "string" then
        local id = p1
        local msgData = split(p2, ":")

        --cut out if not right length
        if msgData[4] ~= nil or msgData[5] == nil then
            if msgData[1] == "$REGISTER$" then
                --debug
                print(textutils.serialize(msgData))

                if not fs.exists("USERS/"..msgData[2]) then
                    local file = fs.open("USERS/"..msgData[2], "w")

                    --password
                    file.writeLine(msgData[3])
                    --age
                    file.writeLine(msgData[4])
                    file.close()

                    rednet.send(id, "$REGISTER$:COMPLETE")

                else
                    rednet.send(id, "$REGISTER$:EXISTS")

                end

            else
                rednet.send(id, "$REGISTER$:ERROR") --make enums for message codes?

            end

        else
            rednet.send(id, "$REGISTER$:LENGTH")

        end

    end

end