chat

local args = {...}
local m = peripheral.find("modem") -- Yay for CC1.6
local hist = {}
local histc = 0
local flines = {}
local nick = "Luca"
local x, y = term.getSize()
local line = 1
local msg = ""

local aes = dofile("/libs/cryptLib").aes()
local utils = dofile("/libs/cryptLib").utils()

local f = fs.open(args[1],"r")

for fline in f.readLine do
    flines[#flines+1] = fline
end
f.close()

f = fs.open(args[2], "r")
local key = textutils.unserialize(f.readLine())
f.close()

local function encrypt(plain)
    plain = utils.stringToByteArray(plain)
    local iv = utils.keygen(16)
    local c_text = aes.encrypt_cbc(plain, key, iv)

    return {c_text, iv}
end

local function decrypt(c_text, iv)
    local plain = aes.decrypt_cbc(c_text, key, iv)

    return utils.byteArrayToString(plain)
end

term.clear()
term.setCursorPos(1,1)

print("Welcome to Chat!")
print("IDs im Chatraum:")

for i = 1,#flines do
    print(flines[i])
    m.open(tonumber(flines[i]))
end

sleep(3)
term.clear()

while true do
    term.setCursorPos(1, y)
 term.setBackgroundColor(colors.gray)
    term.clearLine()
    term.write("Message:"..msg)
 term.setBackgroundColor(32768)
    local e = {os.pullEvent()}
    if e[1] == "char" then
 if nick:len()+2 > 8 then
   add = nick:len()+2
 else
   add = 8
 end
  if msg:len()+add < x then
        msg = msg..e[2]
  end
    elseif e[1] == "modem_message" then
        local c_text, iv = aes.validate(e[5])
        if c_text then
            if line == y -1 then
                term.clear()
                line = 1
            end
   rs.setOutput("left",true)
   sleep(0.1)
   rs.setOutput("left",false)
   term.setCursorPos(1, line)
            local plain = decrypt(c_text, iv)
    term.write(plain)
            line = line + 1
        end

    elseif e[1] == "key" then
        if e[2] == 14 then
            term.setCursorPos(1,1)
            msg = msg:sub(0,#msg-1)

        elseif e[2] == 28 then
   hist[#hist+1] = msg
   if msg:sub(1,1) == "/" then
    local cmd = msg:sub(2,#msg)
    if cmd == "help" then
     lines = {"/logout: Will quit you from the chat","/help: Will list the commands","/nick: Change your Nick","/me: Tell the others what you are doing"}
     if #lines + line >=y then
       term.clear()
       term.setCursorPos(1,1)
       line = 1
     end
     for i = 1,#lines do
     term.setCursorPos(1,line)
     print(lines[i])
     line = line + 1
     end
    elseif cmd:sub(1,4) == "nick" then
     if cmd:sub(6) == "" then

     else
      nick = cmd:sub(6)
     end
    elseif cmd == "logout" then
      local left = "<"..nick.."> left the chat"
      left = encrypt(left)
      m.transmit(os.getComputerID(),os.getComputerID(),left)
      hist = {}
      shell.run("clear")
      break
    elseif cmd:sub(1,2) == "me" then
     if cmd:sub(4) == "" then

     else
      local me = "*"..nick.." "..cmd:sub(4)
      if line == y-1 then
       term.clear()
       line = 1
      end
      term.setCursorPos(1,line)
      print(me)
      line = line + 1
      me = encrypt(me)
      m.transmit(os.getComputerID(),os.getComputerID(),me)
     end
    end
   else
    msg = "<"..nick..">"..msg
            if line == y -1 then
                 term.clear()
                line = 1
            end
            term.setCursorPos(1, line)
            print(msg)
            line = line + 1
            msg = encrypt(msg)
            m.transmit(os.getComputerID(),os.getComputerID(),msg)
   end
   histc = 0
            msg = ""
  elseif e[2] == 200 then
   histc = histc + 1
   if histc > #hist then
    histc = histc - 1
   else
    msg = hist[#hist-histc+1]
   end
  elseif e[2] == 208 then

   histc = histc - 1
   if histc == 0 then
    msg = ""
   elseif histc < 0 then
    histc = histc + 1
   else
    msg = hist[#hist-histc+1]
   end
  end
 end
end