-- Prosody IM

-- Copyright (C) 2008-2013 Matthew Wild

-- Copyright (C) 2008-2013 Waqas Hussain

-- Copyright (C) 2014 Kim Alvefur

--

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

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

--

local new_sasl = require "util.sasl".new;

local base64 = require "util.encodings".base64.encode;

local have_async, async = pcall(require, "util.async");

local log = module._log;

local host = module.host;

local api_base = module:get_option_string("http_auth_url",  ""):gsub("$host", host);

if api_base == "" then error("http_auth_url required") end

local provider = {};

-- globals required by socket.http

if rawget(_G, "PROXY") == nil then

	rawset(_G, "PROXY", false)

end

if rawget(_G, "base_parsed") == nil then

	rawset(_G, "base_parsed", false)

end

if not have_async then -- FINE! Set your globals then

	prosody.unlock_globals()

	require "ltn12"

	require "socket"

	require "socket.http"

	require "ssl.https"

	prosody.lock_globals()

end

local function async_http_auth(url, username, password)

	module:log("debug", "async_http_auth()");

	local http = require "net.http";

	local wait, done = async.waiter();

	local content, code, request, response;

	local ex = {

		headers = { Authorization = "Basic "..base64(username..":"..password); };

	}

	local function cb(content_, code_, request_, response_)

		content, code, request, response = content_, code_, request_, response_;

		done();

	end

	http.request(url, ex, cb);

	wait();

	if code >= 200 and code <= 299 then

		module:log("debug", "HTTP auth provider confirmed valid password");

		return true;

	else

		module:log("debug", "HTTP auth provider returned status code %d", code);

	end

	return nil, "Auth failed. Invalid username or password.";

end

local function sync_http_auth(url,username, password)

	module:log("debug", "sync_http_auth()");

	require "ltn12";

	local http = require "socket.http";

	local https = require "ssl.https";

	local request;

	if string.sub(url, 1, string.len('https')) == 'https' then

		request = https.request;

	else

		request = http.request;

	end

	local _, code, headers, status = request{

		url = url,

		headers = { Authorization = "Basic "..base64(username..":"..password);  }

	};

	if type(code) == "number" and code >= 200 and code <= 299 then

		module:log("debug", "HTTP auth provider confirmed valid password");

		return true;

	else

		module:log("debug", "HTTP auth provider returned status code: "..code);

	end

	return nil, "Auth failed. Invalid username or password.";

end

function provider.test_password(username, password)

	local url = api_base:gsub("$user", username):gsub("$password", password);

	log("debug", "Testing password for user %s at host %s with URL %s", username, host, url);

	if (have_async) then

		return async_http_auth(url, username, password);

	else

		return sync_http_auth(url, username, password);

	end

end

function provider.users()

	return function()

		return nil;

	end

end

function provider.set_password(username, password)

	return nil, "Changing passwords not supported";

end

function provider.user_exists(username)

	return true;

end

function provider.create_user(username, password)

	return nil, "User creation not supported";

end

function provider.delete_user(username)

	return nil , "User deletion not supported";

end

function provider.get_sasl_handler()

	return new_sasl(host, {

		plain_test = function(sasl, username, password, realm)

			return provider.test_password(username, password), true;

		end

	});

end

module:provides("auth", provider);