-- Prosody IM

-- Copyright (C) 2008-2010 Matthew Wild

-- Copyright (C) 2008-2010 Waqas Hussain

-- 

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

local ns_addtimer = require "net.server".addtimer;

local event = require "net.server".event;

local event_base = require "net.server".event_base;

local math_min = math.min

local math_huge = math.huge

local get_time = require "socket".gettime;

local t_insert = table.insert;

local t_remove = table.remove;

local ipairs, pairs = ipairs, pairs;

local type = type;

local data = {};

local new_data = {};

module "timer"

local _add_task;

if not event then

	function _add_task(delay, callback)

		local current_time = get_time();

		delay = delay + current_time;

		if delay >= current_time then

			t_insert(new_data, {delay, callback});

		else

			local r = callback();

			if r and type(r) == "number" then

				return _add_task(r, callback);

			end

		end

	end

	ns_addtimer(function()

		local current_time = get_time();

		if #new_data > 0 then

			for _, d in pairs(new_data) do

				t_insert(data, d);

			end

			new_data = {};

		end

		local next_time = math_huge;

		for i, d in pairs(data) do

			local t, callback = d[1], d[2];

			if t <= current_time then

				data[i] = nil;

				local r = callback(current_time);

				if type(r) == "number" then

					_add_task(r, callback);

					next_time = math_min(next_time, r);

				end

			else

				next_time = math_min(next_time, t - current_time);

			end

		end

		return next_time;

	end);

else

	local EVENT_LEAVE = (event.core and event.core.LEAVE) or -1;

	function _add_task(delay, callback)

		local event_handle;

		event_handle = event_base:addevent(nil, 0, function ()

			local ret = callback();

			if ret then

				return 0, ret;

			elseif event_handle then

				return EVENT_LEAVE;

			end

		end

		, delay);

	end

end

add_task = _add_task;

return _M;