SirChat

--SirChat v1.1.2 -Created by Sir.Mongoose
local IDs = {}
local ex = false
local ID = os.getComputerID()
local cl = false
local line = 0
local targetID = nil
local x = true

function receive()
local senderID, message = rednet.receive()
    if message == "::sirchat" then
        IDs[senderID] = true
        term.clearLine()
        term.setCursorPos(1,line)
    elseif IDs[senderID] == true then
        term.clearLine()
        term.setCursorPos(1,line)
        print("<ID#"..senderID.."> "..(tostring(message)))
        line = line + 1
        table.remove(IDs, senderID)
    else
        term.clearLine()
        term.setCursorPos(1,line)
    end
end

function send()
    term.write("<ID#"..ID.."> ")
    local mesg = read()
    if mesg == "/exit" then
        ex = true
        term.clear()
        term.setCursorPos(1,1)
    elseif mesg == "/commands" then
        print("> '/exit' terminates the program.")
        print("> '/clear' clears chat completely.")
        print("> '/connect' connects you to a different ID.")
        print("> '/info' Tells you about SirChat.")
        line = line + 5
    elseif mesg == "/clear" then
        cl = true
    elseif mesg == "/connect" then
        connect()
    elseif mesg == "/info" then
        print("> SirChat was a program made by Sir.Mongoose.")
        print("> SirChat is currently in version 1.1.2.")
        line = line + 3
    elseif mesg ~= "/exit" or "/commands" or "/clear" or "/connect" or "/info" then
        rednet.broadcast("::sirchat")
        rednet.send((tonumber(targetID)), (tostring(mesg)))
        line = line + 1
    end
end

function chat()
    x = false
    term.clear()
    term.setCursorPos(1,1)
    print("**Connected with ComputerID#"..(tostring(targetID)).."**")
    print("**Type '/commands' for the list of commands**")
    while ex == false do
        parallel.waitForAny(receive, send)
        if line > 17 then
            cl = true
        end
        if cl == true then
            term.clear()
            term.setCursorPos(1,1)
            print("**Connected with ComputerID#"..(tostring(targetID)).."**")
            print("**Type '/commands' for the list of commands**")
            line = 3
            cl = false
        end
    end
end

function numCheck(a)
  if ((tonumber(a)) == nil) == true then
    return false
  else
    return true
   end
end

function connect()
  print("**Enter the ComputerID you want to connect to**")
  line = line + 2
  term.setCursorPos(1,line)
  io.write(">>")
  target = read()

  if numCheck(target) == true then
    targetID = target
    line = line + 1
  else
        while numCheck(target) == false do
            term.setCursorPos(1,line)
            term.clearLine()
            io.write(">>")
            target = read()
        end
    targetID = target
    line = line + 1
  end
    if x == true then
        x = false
        term.clear()
        line = 3
        term.setCursorPos(1,1)
        chat()
    else
        term.setCursorPos(1,1)
        term.clearLine()
        print("**Connected with ComputerID#"..(tostring(targetID)).."**")
        term.setCursorPos(1,line)
  end
end

function connectModem()
term.clear()
term.setCursorPos(1,1)
  if peripheral.isPresent("back") and peripheral.getType("back") == "modem" then
    rednet.open("back")
    connect()
  elseif peripheral.isPresent("front") and peripheral.getType("front") == "modem" then
    rednet.open("front")
    connect()
  elseif peripheral.isPresent("left") and peripheral.getType("left") == "modem" then
    rednet.open("left")
    connect()
  elseif peripheral.isPresent("right") and peripheral.getType("right") == "modem" then
    rednet.open("right")
    connect()
  elseif peripheral.isPresent("top") and peripheral.getType("top") == "modem" then
    rednet.open("top")
    connect()
  elseif peripheral.isPresent("bottom") and peripheral.getType("bottom") == "modem" then
    rednet.open("bottom")
    connect()
  else
    print("**No modem connected, please place one on an available side and press enter**")
    read()
    term.clear()
    term.setCursorPos(1,1)
    connectModem()
   end
end

connectModem()