Wake TV when MacOS wakes from sleep (Hammerspoon)

waketv.lua

local tv_input = "HDMI_2" -- Input to which your Mac is connected
local mac_address = "80:5B:65:6D:AF:D4"
local switch_input_on_wake = true -- Switch input to Mac when waking the TV
local prevent_sleep_when_using_other_input = true -- Prevent sleep when using other input (ie: watching TV)
local debug = false  -- If you run into issues, set to true to enable debug messages

-- You likely will not need to change anything below this line
local tv_name = "MyTV" -- Name of your TV, set when you run `lgtv auth`
local connected_tv_identifiers = {"LG TV", "LG TV SSCR2"} -- Used to identify the TV when it's connected to this computer
local screen_off_command = "off" -- use "screenOff" to keep the TV on, but turn off the screen.
local lgtv_path = "/opt/lgtv-venv/bin/lgtv" -- Full path to lgtv executable
local lgtv_cmd = lgtv_path.." "..tv_name
local app_id = "com.webos.app."..tv_input:lower():gsub("_", "")
local lgtv_ssl = true -- Required for firmware 03.30.16 and up. Also requires LGWebOSRemote version 2023-01-27 or newer.

function lgtv_current_app_id()
  local foreground_app_info = exec_command("getForegroundAppInfo")
  foreground_app_info = string.match(foreground_app_info, '^%b{}')
  foreground_app_info = hs.json.decode(foreground_app_info)
  return foreground_app_info["payload"]["appId"]
end

function tv_is_connected()
  for i, v in ipairs(connected_tv_identifiers) do
    if hs.screen.find(v) ~= nil then
      return true
    end
  end

  return false
end

function dump_table(o)
  if type(o) == 'table' then
    local s = '{ '
    for k,v in pairs(o) do
      if type(k) ~= 'number' then k = '"'..k..'"' end
      s = s .. '['..k..'] = ' .. dump_table(v) .. ','
    end
    return s .. '} '
  else
    return tostring(o)
  end
end

function exec_command(command)
  if lgtv_ssl then
    command = command.." ssl"
  end

  command = lgtv_cmd.." "..command

  if debug then
    print("Executing command: "..command)
  end

  return hs.execute(command)
end

if debug then
  print ("TV name: "..tv_name)
  print ("TV input: "..tv_input)
  print ("LGTV path: "..lgtv_path)
  print ("LGTV command: "..lgtv_cmd)
  print ("SSL: "..tostring(lgtv_ssl))
  print ("App ID: "..app_id)
  print (exec_command("swInfo"))
  print (exec_command("getForegroundAppInfo"))
  print("Connected screens: "..dump_table(hs.screen.allScreens()))
  print("TV is connected? "..tostring(tv_is_connected()))
end

watcher = hs.caffeinate.watcher.new(function(eventType)
  if debug then print("Received event: "..eventType) end

  if not tv_is_connected() then
    if debug then print("TV is not connected. Skipping.") end
    return
  end

  if (eventType == hs.caffeinate.watcher.screensDidWake or
      eventType == hs.caffeinate.watcher.systemDidWake or
      eventType == hs.caffeinate.watcher.sessionDidBecomeActive or
      eventType == hs.caffeinate.watcher.screensDidUnlock) then

    exec_command("on") -- wake on lan
    exec_command("screenOn") -- turn on screen
    hs.execute("/opt/homebrew/bin/wakeonlan "..mac_address)
    if debug then print("TV was turned on") end

    if lgtv_current_app_id() ~= app_id and switch_input_on_wake then
      exec_command("startApp "..app_id)
      if debug then print("TV input switched to "..app_id) end
    end
  end

  if (eventType == hs.caffeinate.watcher.screensDidSleep or
      eventType == hs.caffeinate.watcher.systemWillPowerOff) then

    if lgtv_current_app_id() ~= app_id and prevent_sleep_when_using_other_input then
      if debug then print("TV is currently on another input ("..current_app_id.."). Skipping powering off.") end
      return
    end

    -- This puts the TV in standby mode.
    -- For true "power off" use `off` instead of `screenOff`.
    exec_command(screen_off_command)
    if debug then print("TV screen was turned off with command `"..screen_off_command.."`.") end
  end
end)
watcher:start()

Interesting so the TV is always on in some way, makes sense with the need for the IR receiver to work, there must be other parts also on including the part that lets you connect via CLI!