clockyTesting.lua

local mon = peripheral.find("monitor")
local tzDif = -7
local date = "????-??-??"
local time = "??:?? ??"
local slowWaitTime = 10
local fastWaitTime = 3
local cHour = 0
local cMin = 0
local hrsUntil = 0
local DAY = 0

mon.clear()
mon.setCursorPos(1,1)
mon.setTextScale(4)


os.loadAPI("json")
local json = _G.json
_G.json = nil


local function redraw()
  mon.clear()
  mon.setCursorPos(1,1)
  mon.write(date)
  mon.setCursorPos(1,2)
  mon.write(time)
  mon.setCursorPos(1,5)
  mon.write(tostring(hrsUntil) .. " hrs adv")
end


local function updateDate(yr,mn,d)
  --"????-??-??"
  -- 1234567890
  if type(yr) == "string" then
    date = yr .. date:sub(5)
  end
  if type(mn) == "string" then
    date = date:sub(1,5) .. mn .. date:sub(8)
  end
  if type(d) == "string" then
    if d:len() < 2 then
      d = "0" .. d
    end
    date = date:sub(1,8) .. d
  end
end

local function updateTime(hr,mn)
  --"??:?? ??"
  -- 12345678
  if type(hr) == "string" then
    local ampm = "??"
    local n = tonumber(hr) + tzDif
    if n < 0 then
      n = 24 + n
      updateDate(nil,nil,tostring(DAY-1))
    end
    hrsUntil = 22 - n
    if hrsUntil < 0 then hrsUntil = 24 + hrsUntil end
    if n > 12 then
      ampm = "PM"
      n = n - 12
    elseif n == 12 then
      ampm = "PM"
    elseif n < 12 then
      ampm = "AM"
      if n == 0 then
        n = 12
      end
    end
    n = tostring(n)
    if n:len() < 2 then
      n = "0" .. n
    end
    time = n .. time:sub(3,6) .. ampm
  end
  if type(mn) == "string" then
    time = time:sub(1,3) .. mn .. time:sub(6)
  end
end

redraw()


local function timeWatch()
  while true do
    if cHour == 22 and cMin == 0 then
      mon.clear()
      mon.setCursorPos(1,1)
      mon.setTextScale(1)
      shell.run("monitor right shell")
      mon.setTextScale(4)
    end
    if cHour == 21 then
      if cMin > 55 then
        print()
        mon.setCursorPos(1,3)
        mon.write("ADVENT")
        mon.setCursorPos(1,4)
        mon.write("SOON")
        os.sleep(fastWaitTime)
      else
        os.sleep(slowWaitTime)
      end
    else
      os.sleep(slowWaitTime)
    end
    local h = {http.get("http://worldclockapi.com/api/json/utc/now")}

    if h[1] then
      local data = json.decode(h[1].readAll())
      h[1].close()
      --Date / Time Format:
      --[[
        2018-12-02T06:13:Z
      ]]
      if type(data) == "table" then
        if data["currentDateTime"] then
          local year, month, day, hour, minute = string.match(data["currentDateTime"],"(%d+)-(%d+)-(%d+)T(%d+):(%d+)Z")
          updateDate(year,month,day)
          DAY = tonumber(day)
          updateTime(hour,minute)
          cHour = tonumber(hour)
          cMin = tonumber(minute)
        else
          date = "????-??-?1"
          time = "??:?? ??"
        end
      else
        date = "????-??-?2"
        time = "??:?? ??"
      end
    else
      date = "????-??-?3"
      time = "??:?? ??"
    end
    redraw()
  end
end
timeWatch()