-- Lanforce
-- 	full online objects caching, by setting alife to a max value then restore it to general 250 m
--	this will force all objects inside the level to go online, where their resources get cached

-- Tronex:
--  Switching to max distance will happen on sleeping as well, since squads tend to arrive to their distinations
--  When a squad is created inside (or traveled to) actor level, this script will prefetch the model of its npcs to save resources and reduce the lag when they go online



local enable_debug = false

local enable_feature   = ini_sys:r_bool_ex("alife","auto_switch") or false
local min_dist         = ini_sys:r_float_ex("alife","auto_switch_distance_normal") or 250  --[meters]
local max_dist         = ini_sys:r_float_ex("alife","auto_switch_distance_start") or 2000 --[meters]
local timer_switch     = ini_sys:r_float_ex("alife","auto_switch_timer") or 5000 --[milli-seconds]
local timer_prefetch   = 5000 --[milli-seconds]
local tg_switch        = 0
local tg_prefetch      = 0

local on_max        = false
local prev_level_id = {}
local to_prefetch   = {}
local first_time    = false


function print_debug(fmt, ...)
	if enable_debug then
		printf("-xr_patch | " .. fmt, ...)
	end
end

function switch_distance()
	tg_switch = time_global()
end

function queue_squad(squad)
	if is_far(squad) then
		print_debug("squad [%s] is set to prefetch", squad:name())
		
		for k in squad:squad_members() do
			print_debug("NPC [%s] is set to prefetch", k)
			to_prefetch[k.id] = true
		end
	end
end

function is_online(squad)
	for k in squad:squad_members() do
		local object = db.storage[k.id] and db.storage[k.id].object
		if object then
			return true
		end
	end
	return false
end

function is_far(squad)
	local dist = db.actor:position():distance_to(squad.position)
	print_debug("squad [%s] distance from player is %s meters | far: %s", squad:name(), round(dist), dist > min_dist)
	return dist > min_dist
end


-- Callbacks
local function squad_on_npc_creation(squad, se_obj, spawn_smart)
	if simulation_objects.is_on_the_actor_level(squad)then
		queue_squad(squad)
	end
end

local function squad_on_update(squad)
	local id = squad.id
	if (not prev_level_id[id]) then
		prev_level_id[id] = game_graph():vertex(squad.m_game_vertex_id):level_id()
		return
	end
	
	local curr_level_id = game_graph():vertex(squad.m_game_vertex_id):level_id()
	if (curr_level_id ~= prev_level_id[id]) then
		prev_level_id[id] = curr_level_id
		
		if (curr_level_id == get_player_level_id()) then -- squad arrived to player's level
			queue_squad(squad)
			print_debug("squad [%s] traveled to actor level", squad:name())
		end
	end
end

local function actor_on_update()
	local tg = time_global()
	if tg_switch then
		
		if (not on_max) then
			alife():set_switch_distance(max_dist)
			on_max = true
			print_debug("alife switch distance set to: %s", max_dist)
		end
		
		if (tg > (tg_switch + timer_switch)) then
			alife():set_switch_distance(min_dist)
			on_max = false
			tg_switch = false
			print_debug("alife switch distance set to: %s", min_dist)
			
			-- Callbacks can be set after switching the distance to avoid bloating tables on loading
			if (not first_time) then
				print_debug("registered callbacks", min_dist)
				RegisterScriptCallback("squad_on_npc_creation",squad_on_npc_creation)
				RegisterScriptCallback("squad_on_update",squad_on_update)
				first_time = true
			end
		end
	end
	
	-- Timer to prefetch one model each time
	if on_max or (tg < tg_prefetch + timer_prefetch) then
		return
	end
	tg_prefetch = tg
	
	for id,_ in pairs(to_prefetch) do
		local se_npc = alife_object(id)
		if se_npc then
			print_debug("Prefetch mode start for [%s]", se_npc:name())
			local cls = se_npc:clsid()
			local data = IsStalker(nil,cls) and utils_stpk.get_stalker_data(se_npc) or IsMonster(nil,cls) and utils_stpk.get_monster_data(se_npc)
			if data then
				print_debug("Prefetching: %s", data.visual_name)
				game.prefetch_model(data.visual_name)
			end
			print_debug("Prefetch mode finished for [%s]", se_npc:name())
		end
		to_prefetch[id] = nil
		break
	end
end

local function actor_on_first_update()
	switch_distance()
end

local function actor_on_sleep()
	switch_distance()
end


function on_game_start()
	if (not enable_feature) then
		return
	end
	
	RegisterScriptCallback("actor_on_first_update",actor_on_first_update)
	RegisterScriptCallback("actor_on_update",actor_on_update)
	RegisterScriptCallback("actor_on_sleep",actor_on_sleep)
end