NetCOM (TrashComp)

-------------------------------------------------------------------------------
-- Filename: NetCOM.lua
--
-- Description:
-- A small program that runs in the background to handle command packets
-- received over the network using the "netCOM" protocol
-------------------------------------------------------------------------------

local NAME = os.getComputerLabel()
local ID = os.getComputerID()
local NETWORK_PROTOCOL = "FishNET"

-------------------------------------------------------------------------------
-- Broadcasts a command packet to all computers on the network (currenly not
-- in use)
--
-- Arguments:
-- command  - command to send
-- name     - the name of the computer to send it to
--
-- Returns:
-- ture   - if the command was successful
-- false  - if the command was not successful within 2 seconds
-------------------------------------------------------------------------------

local function sendNetCommand(command, name)
  rednet.broadcast(
  {
    Type = "netCommand",
    Command = command,
    Name = name,
    SenderID = ID,
  }, "netCOM" )
end

-------------------------------------------------------------------------------
-- Waits to receive a command packet over the network using the "netCOM"
-- protocol
--
-- Arguments:
-- None
--
-- Returns:
-- message.Command  - the command sent within the command packet
-- senderID - the ID of the computer that sent the command packet
-------------------------------------------------------------------------------

local function getNetCommand()
  local senderID, message, protocol = rednet.receive(1)

  if protocol == "netCOM" and message.Type == "netCommand" then
    if message.Name == NAME then
      return message.Command, senderID
    end
  end
end

-------------------------------------------------------------------------------
-- Attempts to do the command that was sent in a command packet, then sends a
-- response to the sender to tell it if it was successful or not
--
-- Arguments:
-- None
--
-- Returns:
-- Nothing
-------------------------------------------------------------------------------

local function doNetCommand()
  local command, senderID = getNetCommand()

  if command then
    if shell.run("/programs/" .. command) then
      print(command)
      rednet.send(senderID, "success", NETWORK_PROTOCOL)
    else
      print("Invalid command... " .. command)
      rednet.send(senderID, "invalid", NETWORK_PROTOCOL)
    end
  end
end

-------------------------------------------------------------------------------
-- Waits for redstone input from pressure plate, then sends a command to
-- Tornado to collect trash
--
-- Arguments:
-- none
--
-- Returns:
-- Nothing
-------------------------------------------------------------------------------

local function getRedstoneInput()
  if redstone.getInput("right") == true then
    sendNetCommand("CollectTrash", "Tornado")
  end
end

-------------------------------------------------------------------------------

local function main()
  while true do
    doNetCommand()
    getRedstoneInput()
  end
end

-------------------------------------------------------------------------------

main()