Blockchat_Indev

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

local colorOther, colorReceive, colorMe
colorOther = colors.orange
colorReceive = colors.brown
colorMe = colors.lightBlue

local debugMode = false

print("Run in debug mode? (y/n)")
while true do
  local event, key = os.pullEvent("key")

  if key == keys.y then
    debugMode = true
    break
  elseif key == keys.n then
    debugMode = false
    break
  end
end

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

term.setTextColor(colors.blue)

print("Starting program.\n")

local driveSide

-- check for modem
for _, side in ipairs(rs.getSides()) do
  if peripheral.isPresent(side) and peripheral.getType(side) == "modem" then
    driveSide = side
    break
  end
end

local modem

-- wrap and open modem or send error message
if driveSide then
  print("Modem found, wrapping and opening.")
  modem = peripheral.wrap(driveSide)
  rednet.open(driveSide)
  term.setTextColor(colors.yellow)
  print("\nWelcome to Blockchat!")
  print("Your id is: " .. os.computerID())
else
  error("No modem found, please attach modem and reboot program.")
end

-- message confirmation variables
local sentConfirmation = 0
local justSentMessage = 0

-- deal with all incoming messages
local function receive()

  local id,message,protocol = rednet.receive()

  -- happens when receives message confirmation
  if (justSentMessage == 1 and message == 1) then
    print("Message confirmation received.")
    justSentMessage = 0
    return
  end

  -- resets variable
  sentConfirmation = 0

  term.setTextColor(colorReceive)

  print("Message received.")

  print("Sender Id: " .. id)

  if (message ~= null) then
    term.setTextColor(colorOther)
    print("Msg: " .. message)
  end

  if (debugMode) then
    term.setTextColor(colorReceive)
    if (protocol ~= null) then
      print("Protocol: " .. protocol)
    else
      print("Protocol: null")
    end
  end

  -- send confirmation response
  if (sentConfirmation == 0) then
    rednet.send(id,1)
    sentConfirmation = 1
  end

  -- resets variable
  justSentMessage = 0

end

-- send message
local function send()
  term.setTextColor(colorMe)
  --if (justSentMessage == 0) then
    print("\nType target ID: ")
  --end
  os.pullEvent("char")
  local targetId = tonumber(read())
  print("Type message:")
  term.setTextColor(colorMe)
  rednet.send(targetId,read())
  print("Sending message...")
  justSentMessage = 1
end

-- wait for Events
while true do
  parallel.waitForAny(receive, send)
end