main

rednet.open("right")
rednet.host("LCTu", "lct_central")

local Levels = {
  ["Thomas"] = 1,
  ["Paddi"] = 2
}

local queue = {}
local idle = true
local dest = nil

dest = "Thomas"

while true do
  print("Looping.")
  if idle and #queue > 0 then
    print("Accepting a request,")
    idle = false
    local req = table.remove(queue, 1)
    local acc = {type = "accept_sending"}
    rednet.send(req.src, acc, "LCTu")
    dest = req.dest
  end

  local event, id, msg, prot =
    os.pullEvent()
  if event == "rednet_message" and
    prot == "LCTu" then
    print("Received a message.")
    if msg.type == "request_sending" then
      print("Received a new request.")
      local req = {src = id, dest = msg.dest}
      table.insert(queue, req)
    end
  end
  if event == "redstone" and
    rs.getInput("back") then
    print("Items landed.")
    local lvl = 0
    if Levels[dest] ~= nil then
      lvl = Levels[dest]
    end
    print("Destination is "..dest)
    rs.setAnalogOutput("left", lvl)
    os.sleep(0.2)
    rs.setAnalogOutput("left", 0)
    os.sleep(0.2)
    idle = true
  end
end