main

local mon = peripheral.wrap("top")

local t = {text = "help", ymin = 1, ymax = 6, xmin = 8, xmax = 30, txCol = colours.black, bgCol = colours.lime}

function writeButton(_table)
  for i,v in pairs(_table) do
    ytxt = (v.ymin + v.ymax) / 2
    xtxt = (v.xmin + v.xmax) / 2 - string.len(v.text)
    mon.setCursorPos(xtxt, ytxt)
    mon.write(v.text)
    mon.setTextColour(v.txCol)
    mon.setBackgroundColour(v.bgCol)
  end
end

function isValidClick(_table, mx, my)
  for i, v in pairs(_table) do
    if mx <= v.xmax and mx >= v.xmin and my <= v.ymax and my >= v.ymin then
      f = v.text
    end
  return false
  end
end

writeButton(t)

while true do
  event, but, x, y = os.pullEvent("monitorTouch")
  isValidClick(t, x, y)
  if f == help then
    mon.print('hellp')
  end
end