term.clear() --Clear any text
term.setCursorPos(1,1) --Set cursor position to beginning
write"This is not a user-accessible computer." -- User information
write"Log in at one of the USER PCs." --User information
print("")
local firstCycle = true -- Used to determine whether to run bootUp function. Boolean variable
local validSender = false --Used to determine whether valid information has been entered. Boolean variable
local modemSide = "top" --Determines modem side. String variable
local valid = false --Used to determine whether check is made as to whether to return password or not. Boolean variable
local DeBug = true -- turns off prints so people cant see passwrds
users = {{uname = "XenoG", pword = "pl455ey"},
{uname = "Test", pword = "user"},
{uname = "Xenogene", pword = "lolgasm"}
} --Users table. Left is key, right is value. In effect Username-Password (Key-Value)
senders = {18,20} --Table of all computer ID's that can access server.
function bootUp() --New function "bootUp()"
rednet.open(modemSide) --Sends message to rednet to make sure the modem is open
end --End function
local function printTEST(...) -- allows you to turn off prints of ueser name set local DeBug = true to local DeBug = false
if DeBug then
  print(...)
end
end
while true do --Main server loop
validSender = false --set validSender to false. Needs to be done every loop round
local user = nil
local password = nil

if firstCycle then --If the this is the first cycle then
  bootUp() --Call the bootUp() function
end --End IF statement
senderId, message, distance = rednet.receive() --rednet.receive() function call. Loop waits here until a message is received
for i,v in ipairs(senders) do --For index, value, search in the table senders, then execute next line
  if v == senderId then --If v is equal to a senderId (found in senders table) then
   validSender = true --Set validSender to true
   break --Break the loop
  end --End IF statement
end --End FOR loop
if validSender then --If validSender is true, execute next line
  printTEST("MES "..message)
  for k,v in pairs(users) do --For index, value, search in the table users, then execute next line
   printTEST(k..")U "..v.uname.." P "..v.pword)
   if message == v.uname then --If k is equal to message (found in users table) then
    valid = true --Set valid to true
    password = v.pword -- Set password to the value of v
    user = v.uname
    break -- this is needed so valid = false isnt called
   else --Otherwise
    valid = false --Set valid to false
   end --End IF statement
  end --End FOR loop

  if valid then --If valid is true, execute next line
   rednet.send(senderId, password) -- Send the senderID and the password to rednet
   printTEST("Sent "..senderId.." "..password)
   print("User "..user.." Requested Login")
  else --Otherwise
   rednet.send(senderId, "Not Valid") --Send a Not Valid message to rednet
   printTEST("Sent "..senderId.." ".."Not Valid")
   print("Atempted Login Failed")
  end --End IF statement
end --End IF statement
end --End WHILE TRUE DO loop