cfxObjectDestructDetector = {}
cfxObjectDestructDetector.version = "2.0.0" 
cfxObjectDestructDetector.verbose = false 
cfxObjectDestructDetector.requiredLibs = {
	"dcsCommon", -- always
	"cfxZones", -- Zones, of course 
}
--[[--
   VERSION HISTORY 
   1.0.0 initial version, based on parashoo, arty zones  
   1.0.1 fixed bug: trigger.MISC.getUserFlag()
   1.1.0 added support for method, f! and destroyed! 
   1.2.0 DML / Watchflag support 
   1.3.0 Persistence support 
   2.0.0 dmlZone OOP support 
		 clean-up 
         re-wrote object determination to not be affected by 
		 ID changes (happens with map updates)
		 fail addZone when name property is missing 
--]]--

cfxObjectDestructDetector.objectZones = {}

--
-- C A L L B A C K S 
-- 
cfxObjectDestructDetector.callbacks = {}
function cfxObjectDestructDetector.addCallback(theCallback)
	table.insert(cfxObjectDestructDetector.callbacks, theCallback)
end

function cfxObjectDestructDetector.invokeCallbacksFor(zone)
	for idx, theCB in pairs (cfxObjectDestructDetector.callbacks) do 
		theCB(zone, zone.ID, zone.name, zone.objName)
	end
end

--
-- zone handling
--
function cfxObjectDestructDetector.addObjectDetectZone(aZone)
	-- add landHeight to this zone 
	table.insert(cfxObjectDestructDetector.objectZones, aZone)
end

function cfxObjectDestructDetector.getObjectDetectZoneByName(aName)
	for idx, aZone in pairs(cfxObjectDestructDetector.objectZones) do 
		if aZone.name == aName then return aZone end 
	end
	-- add landHeight to this zone 
	return nil
end

--
-- processing of zones 
--
function cfxObjectDestructDetector.processObjectDestructZone(aZone)
	if aZone:hasProperty("name") then 
		aZone.objName = string.upper(aZone:getStringFromZoneProperty("NAME", "default"))
	else 
		trigger.action.outText("+++OOD: Zone <" .. aZone.name .. "> lacks name attribute, ignored for destruct detection.")
		return false
	end 
	
	-- persistence interface
	aZone.isDestroyed = false 
	
	aZone.oddMethod = aZone:getStringFromZoneProperty("method", "inc")
	if aZone:hasProperty("oddMethod") then 
		aZone.oddMethod = aZone:getStringFromZoneProperty("oddMethod", "inc")
	end
	
	if aZone:hasProperty("f!") then 
		aZone.outDestroyFlag = aZone:getStringFromZoneProperty("f!", "*none")
	elseif aZone:hasProperty("destroyed!") then 
		aZone.outDestroyFlag = aZone:getStringFromZoneProperty("destroyed!", "*none")
	elseif aZone:hasProperty("objectDestroyed!") then 
		aZone.outDestroyFlag = aZone:getStringFromZoneProperty( "objectDestroyed!", "*none")
	end
	return true 
end
--
-- ON EVENT
--
function cfxObjectDestructDetector:onEvent(event)
	if event.id == world.event.S_EVENT_DEAD then
		if not event.initiator then return end 
		local theObject = event.initiator
		local desc = theObject:getDesc() 
		if not desc then return end 
		local matchMe = desc.typeName -- we home in on object's typeName 
		if not matchMe then return end 
		matchMe = string.upper(matchMe)
		
		for idx, aZone in pairs(cfxObjectDestructDetector.objectZones) do 
			if (not aZone.isDestroyed) and aZone.objName == matchMe then 
				if aZone.outDestroyFlag then 
					aZone:pollFlag(aZone.outDestroyFlag, aZone.oddMethod)
				end
				-- invoke callbacks 
				cfxObjectDestructDetector.invokeCallbacksFor(aZone)
				if aZone.verbose or cfxObjectDestructDetector.verbose then 
					trigger.action.outText("OBJECT KILL: " .. id, 30)
				end
				-- save state for persistence
				aZone.isDestroyed = true 				
				return 
			end
		end
		
    end
	
end

--
-- persistence: save and load data 
--
function cfxObjectDestructDetector.saveData() -- invoked by persistence
	local theData = {}
	local zoneInfo = {}
	for idx, aZone in pairs(cfxObjectDestructDetector.objectZones) do
		-- save all pertinent info. in our case, it's just 
		-- the isDestroyed and flag info info
		info = {}
		info.isDestroyed = aZone.isDestroyed
		info.outDestroyVal = aZone:getFlagValue(aZone.outDestroyFlag)
		zoneInfo[aZone.name] = info
	end
	-- expasion proof: assign as own field
	theData.zoneInfo = zoneInfo
	return theData
end

function cfxObjectDestructDetector.loadMission()
	if cfxObjectDestructDetector.verbose then 
		trigger.action.outText("+++oDDet: persistence - loading data", 30)
	end
	
	local theData = persistence.getSavedDataForModule("cfxObjectDestructDetector")
	if not theData then 
		return 
	end
	
	-- iterate the data, and fail graciously if 
	-- we can't find a zone. it's probably beed edited out
	local zoneInfo = theData.zoneInfo
	if not zoneInfo then return end 
	if cfxObjectDestructDetector.verbose then 
		trigger.action.outText("+++oDDet: persistence - processing data", 30)
	end	
	
	for zName, info in pairs (zoneInfo) do 
		local theZone = cfxObjectDestructDetector.getObjectDetectZoneByName(zName)
		if theZone then 
			theZone.isDestroyed = info.isDestroyed
			theZone:setFlagValue(theZone.outDestroyFlag, info.outDestroyVal)
			if cfxObjectDestructDetector.verbose or theZone.verbose then 
				trigger.action.outText("+++oDDet: persistence setting flag <" .. theZone.outDestroyFlag .. "> to <" .. info.outDestroyVal .. ">",30)
			end
			local theName = tostring(theZone.ID)
			if info.isDestroyed then 
				-- We now get the scenery object in that zone 
				-- and remove it
				-- note that dcsCommon methods use DCS zones, not cfx
				local theObject = dcsCommon.getSceneryObjectInZoneByName(theName, theZone.dcsZone)
				if theObject then 
					if cfxObjectDestructDetector.verbose or theZone.verbose then 
						trigger.action.outText("+++oDDet: persistence removing dead scenery object <" .. theName .. ">",30)
					end
					theObject:destroy()
				else 
					if cfxObjectDestructDetector.verbose or theZone.verbose then 
						trigger.action.outText("+++oDDet: persistence - can't find scenery objects <" .. theName .. ">, skipped destruction",30)
					end
				end
			else 
				if cfxObjectDestructDetector.verbose or theZone.verbose then 
					trigger.action.outText("+++oDDet: persistence - scenery objects <" .. theName .. "> is healthy",30)
				end
			end
		else 
			trigger.action.outText("+++oDDet: persistence - can't find detector <" .. zName .. "> on load. skipping", 30)
		end
	end
	if cfxObjectDestructDetector.verbose then 
		trigger.action.outText("+++oDDet: persistence - processing complete", 30)
	end	
end

--
-- start
--

function cfxObjectDestructDetector.start()
	if not dcsCommon.libCheck("cfx Object Destruct Detector", 
		cfxObjectDestructDetector.requiredLibs) then
		return false 
	end
	
	-- collect all zones with 'OBJECT ID' attribute 
	local attrZones = cfxZones.getZonesWithAttributeNamed("OBJECT ID")
	

	for k, aZone in pairs(attrZones) do 
		if cfxObjectDestructDetector.processObjectDestructZone(aZone) then 
			cfxObjectDestructDetector.addObjectDetectZone(aZone)
		end
	end

	-- add myself as event handler
	world.addEventHandler(cfxObjectDestructDetector)
	
	-- persistence: see if we have any data to process 
	-- for all our zones, and sign up for data saving 
	if persistence and persistence.active then 
		-- sign up for saves 
		callbacks = {}
		callbacks.persistData = cfxObjectDestructDetector.saveData
		persistence.registerModule("cfxObjectDestructDetector", callbacks)
		
		if persistence.hasData then
			cfxObjectDestructDetector.loadMission()
		end
	else 
		if cfxObjectDestructDetector.verbose then 
			trigger.action.outText("no persistence for cfxObjectDestructDetector", 30)
		end
	end
	
	-- say hi
	trigger.action.outText("cfx Object Destruct Zones v" .. cfxObjectDestructDetector.version .. " started.", 30)
	return true 
end

-- let's go 
if not cfxObjectDestructDetector.start() then 
	trigger.action.outText("cf/x Object Destruct Zones aborted: missing libraries", 30)
	cfxObjectDestructDetector = nil 
end