-- 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 usermanager = require "core.usermanager";
local new_sasl = require "util.sasl".new;
local saslprep = require "util.encodings".stringprep.saslprep;
local secure_equals = require "util.hashes".equals;

local log = module._log;
local host = module.host;

local accounts = module:open_store("accounts");

-- define auth provider
local provider = {};

function provider.test_password(username, password)
	log("debug", "test password for user '%s'", username);
	local credentials = accounts:get(username) or {};
	password = saslprep(password);
	if not password then
		return nil, "Password fails SASLprep.";
	end

	if secure_equals(password, saslprep(credentials.password)) then
		return true;
	else
		return nil, "Auth failed. Invalid username or password.";
	end
end

function provider.get_password(username)
	log("debug", "get_password for username '%s'", username);
	return (accounts:get(username) or {}).password;
end

function provider.set_password(username, password)
	log("debug", "set_password for username '%s'", username);
	password = saslprep(password);
	if not password then
		return nil, "Password fails SASLprep.";
	end
	local account = accounts:get(username);
	if account then
		account.password = password;
		return accounts:set(username, account);
	end
	return nil, "Account not available.";
end

function provider.user_exists(username)
	local account = accounts:get(username);
	if not account then
		log("debug", "account not found for username '%s'", username);
		return nil, "Auth failed. Invalid username";
	end
	return true;
end

function provider.users()
	return accounts:users();
end

function provider.create_user(username, password)
	password = saslprep(password);
	if not password then
		return nil, "Password fails SASLprep.";
	end
	return accounts:set(username, {password = password});
end

function provider.delete_user(username)
	return accounts:set(username, nil);
end

function provider.get_sasl_handler()
	local getpass_authentication_profile = {
		plain = function(_, username, realm)
			local password = usermanager.get_password(username, realm);
			if not password then
				return "", nil;
			end
			return password, true;
		end
	};
	return new_sasl(host, getpass_authentication_profile);
end

module:provides("auth", provider);