Scripting/Engine: Change to how groups are handled?

--Credit to shnicklefritz
--https://forums.eagle.ru/showpost.php?p=3406607&postcount=3

function onShutdownAI(event)

if world.event.S_EVENT_ENGINE_SHUTDOWN == event.id and event.initiator:getPlayerName() == nil then
local shutdownGroup = event.initiator:getGroup()
local shutdownType = event.initiator:getTypeName()
local shutdownCall = event.initiator:getCallsign()
local shutdownID = event.initiator:getID()
local shutdownName = shutdownGroup:getName()
local shutdownSide = shutdownGroup:getCoalition()
local shutdownMess1 = " has returned to base. We are getting another one in air ASAP."

	if shutdownGroup:getSize() >= 1 and event.initiator:inAir() == false then
	local shutdownAir = 0

		for i, ship in pairs (shutdownGroup:getUnits()) do
			if ship:inAir() == true then
			
			local shutdownAir = shutdownAir + 1
			end
		end
		
		if shutdownAir == 0 then
			trigger.action.deactivateGroup(shutdownGroup)
			trigger.action.outTextForCoalition(shutdownSide, "A friendly " .. shutdownType .. ", callsign " .. shutdownCall .. shutdownMess1, 15)


			if shutdownType == "E-2C" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "KC130" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "MiG-21Bis" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "MiG-29A" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "MiG-23MLD" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "MiG-25PD" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "KC-135" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "Su-24M" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "F-15E" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "F-5E-3" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "A-10C" then mist.respawnGroup(shutdownName, true)
			elseif shutdownType == "A-10C" then mist.respawnGroup(shutdownName, true)
			end
		end
	end
end
end

mist.addEventHandler(onShutdownAI)