-- LUALOCALS < ---------------------------------------------------------
local minetest, pairs, string, tonumber
    = minetest, pairs, string, tonumber
local string_format
    = string.format
-- LUALOCALS > ---------------------------------------------------------

local modname = minetest.get_current_modname()

local invert = minetest.settings:get_bool(modname .. "_invert")
local timeout = tonumber(minetest.settings:get(modname .. "_timeout")) or 600
local reason = minetest.settings:get(modname .. "_reason") or "idle timeout"

minetest.register_privilege(modname, {
		description = (invert and "Kick" or "Do not kick") .. " this player when idle",
		give_to_singleplayer = false,
		give_to_admin = false
	})

local function now() return minetest.get_us_time() / 1000000 end

local times = {}
local actions = {}

minetest.register_chatcommand(modname, {
		description = "Check player idle time and last action",
		privs = {server = true},
		func = function(_, param)
			local time = times[param]
			if not time then
				return true, string_format("Player %q not found", param)
			end
			local active = (not minetest.check_player_privs(param, modname))
			== (not invert)
			return true, string_format(
				"Player %q idle %0.2f/%s last action %q",
				param,
				now() - time,
				active and string_format("%.2f", timeout) or "never",
				actions[param] or "unknown")
		end
	})

local function bumpn(pname, action)
	times[pname] = now()
	actions[pname] = action
end
local function bump(player, action)
	if not (player and player.get_player_name) then return end
	local pname = player:get_player_name()
	if not pname then return end
	return bumpn(pname, action)
end

local function wrapon(event, idx, func)
	minetest["register_on_" .. event](function(...)
			return func(({...})[idx], event)
		end)
end
wrapon("joinplayer", 1, bump)
wrapon("placenode", 3, bump)
wrapon("dignode", 3, bump)
wrapon("punchnode", 3, bump)
wrapon("chat_message", 1, bumpn)
wrapon("player_receive_fields", 1, bump)
wrapon("craft", 2, bump)
wrapon("player_inventory_action", 1, bump)

local looks = {}
local ctlbits = {}
local function checkplayer(player, pname)
	local bits = player:get_player_control_bits()
	local oldbits = ctlbits[pname]
	ctlbits[pname] = bits

	local look = player:get_look_dir()
	local oldlook = looks[pname]
	looks[pname] = look

	if bits ~= oldbits then
		return bumpn(pname, "control")
	elseif not (oldlook and vector.distance(look, oldlook) < 0.001) then
		return bumpn(pname, "lookdir")
	end
end
minetest.register_globalstep(function()
		for _, player in pairs(minetest.get_connected_players()) do
			if (not minetest.check_player_privs(player, modname)) ~= (not invert) then return end
			local pname = player:get_player_name()
			checkplayer(player, pname)
			if now() - times[pname] >= timeout then
				minetest.kick_player(pname, reason)
			end
		end
	end)