if not minetest.create_metric then
	return
end

local storage = minetest.get_mod_storage()
local function counter(name, help)
	local metric = minetest.create_metric("counter", name, help)
	metric:increment(tonumber(storage:get(name) or 0))
	return {
		get = function()
			return metric:get()
		end,

		increment = function(_, value)
			metric:increment(value)
			storage:set_string(name, tostring(metric:get()))
		end,
	}
end
local function gauge(name, help)
	return minetest.create_metric("gauge", name, help)
end


--
-- Kills
--
local kill_counter = counter("ctf_kills", "Total kills")
ctf.register_on_killedplayer(function(victim, killer, type)
	kill_counter:increment()
end)


--
-- Damage
--
local punch_counter = counter("ctf_punches", "Total punches")
local damage_counter = counter("ctf_damage_given", "Total damage given")
ctf.register_on_attack(function(_, _, _, _, _, damage)
	punch_counter:increment()
	damage_counter:increment(damage)
end)

--
-- Digs / places
--
local dig_counter = counter("ctf_digs", "Total digs")
local place_counter = counter("ctf_places", "Total digs")
minetest.register_on_dignode(function()
	dig_counter:increment()
end)
minetest.register_on_placenode(function()
	place_counter:increment()
end)


local online_score = gauge("ctf_online_score", "Total score of online players")
local match_time = gauge("ctf_match_play_time", "Current time in match")
minetest.register_globalstep(function()
	local sum = 0
	for _, player in pairs(minetest.get_connected_players()) do
		local total, _ = ctf_stats.player(player:get_player_name())
		sum = sum + total.score
	end
	online_score:set(sum)

	match_time:set(ctf_match.get_match_duration() or 0)
end)