-- Prosody IM v0.4

-- Copyright (C) 2008-2009 Matthew Wild

-- Copyright (C) 2008-2009 Waqas Hussain

-- 

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

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

--

local select = select;

local t_insert = table.insert;

local pairs = pairs;

local next = next;

module "multitable"

local function get(self, ...)

	local t = self.data;

	for n = 1,select('#', ...) do

		t = t[select(n, ...)];

		if not t then break; end

	end

	return t;

end

local function add(self, ...)

	local t = self.data;

	local count = select('#', ...);

	for n = 1,count-1 do

		local key = select(n, ...);

		local tab = t[key];

		if not tab then tab = {}; t[key] = tab; end

		t = tab;

	end

	t_insert(t, (select(count, ...)));

end

local function set(self, ...)

	local t = self.data;

	local count = select('#', ...);

	for n = 1,count-2 do

		local key = select(n, ...);

		local tab = t[key];

		if not tab then tab = {}; t[key] = tab; end

		t = tab;

	end

	t[(select(count-1, ...))] = (select(count, ...));

end

local function r(t, n, _end, ...)

	if t == nil then return; end

	local k = select(n, ...);

	if n == _end then

		t[k] = nil;

		return;

	end

	if k then

		if v then

			r(v, n+1, _end, ...);

			if not next(v) then

				t[k] = nil;

			end

		end

	else

		for _,b in pairs(t) do

			r(b, n+1, _end, ...);

			if not next(b) then

				t[_] = nil;

			end

		end

	end

end

local function remove(self, ...)

	local _end = select('#', ...);

	for n = _end,1 do

		if select(n, ...) then _end = n; break; end

	end

	r(self.data, 1, _end, ...);

end

local function s(t, n, results, _end, ...)

	if t == nil then return; end

	local k = select(n, ...);

	if n == _end then

		if k == nil then

			for _, v in pairs(t) do

				t_insert(results, v);

			end

		else

			t_insert(results, t[k]);

		end

		return;

	end

	if k then

		if v then

			s(v, n+1, results, _end, ...);

		end

	else

		for _,b in pairs(t) do

			s(b, n+1, results, _end, ...);

		end

	end

end

-- Search for keys, nil == wildcard

local function search(self, ...)

	local _end = select('#', ...);

	for n = _end,1 do

		if select(n, ...) then _end = n; break; end

	end

	local results = {};

	s(self.data, 1, results, _end, ...);

	return results;

end

-- Append results to an existing list

local function search_add(self, results, ...)

	if not results then results = {}; end

	local _end = select('#', ...);

	for n = _end,1 do

		if select(n, ...) then _end = n; break; end

	end

	s(self.data, 1, results, _end, ...);

	return results;

end

function new()

	return {

		data = {};

		get = get;

		add = add;

		set = set;

		remove = remove;

		search = search;

		search_add = search_add;

	};

end

return _M;