mystPortalDial

local backgroundColor = colors.blue
local altBackgroundColor = colors.lightBlue
local greetingOne = "Please choose your"
local greetingTwo = "destination"
local timerDelay = 8

-- computer front points northward
local dirs = {front="north",left="east",back="south",right="west"}
local dir = nil

local mon = peripheral.find("monitor")

local chest = nil
local slot = nil

for i,v in pairs(rs.getSides()) do
  if peripheral.getType(v) == "ender_chest" then
    chest = peripheral.wrap(v)
    dir = dirs[v]
  elseif peripheral.getType(v) == "book_receptacle" then
    slot = peripheral.wrap(v)
  end
end

if not chest or not dir or not slot or not mon then print("Error while trying to find chest, slot or monitor"); error() end

function removeActiveBook()
  if slot.getStackInSlot(1) then
    if slot.pushItem(dir,1,1) ~= 1 then print("Error while moving book to chest"); error() end
  end
end

removeActiveBook()
sleep(1)

local nDest = 4
local destTable = {}
local timer = nil

function padStr(str, len)
  if #str > len then do return string.sub(str,1,len) end
  else do return str .. string.rep(' ', len - #str) end
  end
end

function waitForTouchEvent()
  repeat
    event, side, monX, monY = os.pullEvent() --"monitor_touch")
    if event == "timer" and side == timer then
      removeActiveBook()
      drawUserInterface()
    end
  until event == "monitor_touch"
  removeActiveBook()
  if nDest > 0 and (monY-3 > 0) and (monY-3 <= nDest) then
    if slot.pullItem(dir,destTable[monY - 3],1) ~= 1 then print("Error while moving book to slot") end
    timer = os.startTimer(timerDelay)
  end
end

function drawUserInterface()
  destTable = {}
  local books = chest.getAllStacks()
  local monX, monY = mon.getSize()
  mon.setBackgroundColor(backgroundColor)
  mon.clear()
  mon.setCursorPos(1,1)
  mon.write(greetingOne)
  mon.setCursorPos(1,2)
  mon.write(greetingTwo)
  nDest = 0
  local i = 0
  for n,book in pairs(books) do
    if book.rawName == "item.myst.linkbook" then
      i = i + 1
      destTable[i] = n
      mon.setCursorPos(1, i + 3)
      if (i % 2 == 0) then
        mon.setBackgroundColor(altBackgroundColor)
      else
        mon.setBackgroundColor(backgroundColor)
      end
      name = padStr(book.destination,monX)
      mon.write(name)
    end
  end
  if not i then
    mon.setCursorPos(1, 4)
    mon.write("No Entries")
  end
  nDest = #destTable
end

while true do
  drawUserInterface()
  waitForTouchEvent()
end