-- Determine variables, tables, functions, APIs
os.loadAPI("button")
local modem = nil
local monitor = nil
local result = nil
local spawnerCount = 0
local greatestLength = 1
local spawners = {}
local sides = {"front", "back", "left", "right", "top", "bottom"}
local default = 1
local id = tonumber(os.getComputerID())
local label = os.getComputerLabel()
local function event(timeout)
  local result = {}
  local eventFunction  = function()
    result = { os.pullEvent() }
    if result[1] == "monitor_touch" or result[1] == "modem_message" then
      returnValue = true
    end
  end
  parallel.waitForAny(function() sleep(timeout) end, eventFunction)
  if returnValue then return result end
end
--Determine which sides the peripherals are located
for i=1, #sides do
  if peripheral.getType(sides[i]) == "modem" then
    modem = peripheral.wrap(sides[i])
  elseif peripheral.getType(sides[i]) == "monitor" then
    monitor = peripheral.wrap(sides[i])
  end
end
if modem == nil or monitor == nil then
  print("Modem/Monitor not found, please attach peripheral.")
end

--Open a channelto receive messages
modem.open(default) modem.transmit(default, default, "ping")

while true do

  --Reset some variables
  wireless = false
  touch = false

  --Wait for an event(button or wireless)
  result = { os.pullEvent() }
  if result[1] == "modem_message" then
    senderChannel = result[3]
    replyChannel = result[4]
    message = result[5]
    wireless = true
  elseif result[1] == "monitor_touch" then
    xTouch = result[3]
    yTouch = result[4]
    touch = true
  end

  if wireless then
    --If the event was a message,
    --react to message
    if string.find(message, "Spawner") ~= nil then
      local subtract = string.gsub(message, "Spawner ", '')
      spawners[subtract] = { channel = tonumber(replyChannel), status = false, link = false, name = tostring(subtract) }
    end

    --Send a message back to available computers
    for k,v in pairs(spawners) do
      if not v.link then
        modem.transmit(tonumber(v.channel), default, "loop")
        spawners[k].link = true
        spawnerCount = spawnerCount + 1
      end
    end
  end

  if touch then
    --Touch, I remember, 'touch.'
    button.checkxy(xTouch, yTouch)
  end

  --monitor stuff
    button.heading("Spawner Control System")

  for k,v in pairs(spawners) do
    --determine longest spawner name
    if string.len(v.name) > greatestLength then
      greatestLength = string.len(v.name)
    end
  end
  --monitor math
  local xMon, yMon = monitor.getSize()
  local position = {}
  local buttonSize = greatestLength + 4
  local possibleButtonRows = math.floor((xMon - 4)/buttonSize) local possibleButtonColumns = math.floor((yMon - 3)/3)
  local possibleButtons = possibleButtonRows*possibleButtonColumns
  if spawnerCount <= possibleButtons then
    for i=1, possibleColumns do
      if i == 1 then
        position[xMin][i] = 2
        position[xMax][i] = position[xMin][i]+ buttonSize
      else
        position[xMin][i] = position[xMin][i-1]+2
        position[xMax][i] = [position[xMin][i] + buttonSize
      end
    end
    for i=1, possibleRows do
      if i == 1 then
        position[yMin][i] = 3
        position[yMax][i] = position[yMin][i] + 3
      else
        position[yMin][i] = position[yMin][i-1] + 3
        position[yMax][i] = position[yMin][i] + 3
      end
    end
  else print("Need more monitors")
  end


  --create button out of spawner table
  local buttonCurrent = 1

  for k,v in pairs(spawners) do
    button.setTable(v.name, func, xmin, xmax, ymin, ymax)
    buttonCurrent = buttonCurrent + 1
  end
end