-- Prosody IM

-- Copyright (C) 2008-2010 Matthew Wild

-- Copyright (C) 2008-2010 Waqas Hussain

-- Modifications copyright (C) 2014 mrDoctorWho

-- 

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

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

--

local st = require "util.stanza";

local dataform_new = require "util.dataforms".new;

local usermanager_user_exists = require "core.usermanager".user_exists;

local usermanager_create_user = require "core.usermanager".create_user;

local usermanager_set_password = require "core.usermanager".set_password;

local usermanager_delete_user = require "core.usermanager".delete_user;

local os_time = os.time;

local nodeprep = require "util.encodings".stringprep.nodeprep;

local jid_bare = require "util.jid".bare;

local timer = require "util.timer";

local math = require "math";

local captcha = require "captcha";

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

local sha1 = require "util.hashes".sha1;

local captcha_ids = {};

local config = module:get_option("captcha_config") or {};

local compat = module:get_option_boolean("registration_compat", true);

local allow_registration = module:get_option_boolean("allow_registration", false);

local additional_fields = module:get_option("additional_registration_fields", {});

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

local field_map = {

	username = { name = "username", type = "text-single", label = "Username", required = true };

	password = { name = "password", type = "text-private", label = "Password", required = true };

	nick = { name = "nick", type = "text-single", label = "Nickname" };

	name = { name = "name", type = "text-single", label = "Full Name" };

	first = { name = "first", type = "text-single", label = "Given Name" };

	last = { name = "last", type = "text-single", label = "Family Name" };

	email = { name = "email", type = "text-single", label = "Email" };

	address = { name = "address", type = "text-single", label = "Street" };

	city = { name = "city", type = "text-single", label = "City" };

	state = { name = "state", type = "text-single", label = "State" };

	zip = { name = "zip", type = "text-single", label = "Postal code" };

	phone = { name = "phone", type = "text-single", label = "Telephone number" };

	url = { name = "url", type = "text-single", label = "Webpage" };

	date = { name = "date", type = "text-single", label = "Birth date" };

	-- something new

	formtype = { name = "FORM_TYPE", type = "hidden"};

	captcha_text = { name = "captcha_text", type = "fixed", label = "Warning: "};

	captcha_psi = { name = "captchahidden", type = "hidden" }; -- Don't know exactly why, but it exists in ejabberd register form

	captcha_url = { name = "url", type = "text-single", label = "Captcha url"};

	from = { name = "from", type = "hidden" };

	captcha_challenge = { name = "challenge", type = "hidden" };

	sid = { name = "sid", type = "hidden" };

	ocr = { name = "ocr", label = "Enter shown text", required = true, type = "media" }

};

local registration_form = dataform_new{

	field_map.formtype;

	field_map.username;

	field_map.password;

	field_map.captcha_text;

--	field_map.captcha_psi; -- Maybe later, i really have no idea why it used in ejabberd reg form

	field_map.captcha_url;

	field_map.from;

	field_map.captcha_challenge;

	field_map.sid;

	field_map.ocr;

};

function delete_captcha(cid)

	os.remove(string.format("%s/%s.png", config.dir, cid))

	captcha_ids[cid] = nil;

end

for _, field in ipairs(additional_fields) do

	if type(field) == "table" then

		registration_form[#registration_form + 1] = field;

	else

		if field:match("%+$") then

			field = field:sub(1, #field - 1);

			field_map[field].required = true;

		end

		registration_form[#registration_form + 1] = field_map[field];

		registration_query:tag(field):up();

	end

end

module:add_feature("jabber:iq:register");

local register_stream_feature = st.stanza("register", {xmlns="http://jabber.org/features/iq-register"}):up();

module:hook("stream-features", function(event)

        local session, features = event.origin, event.features;

	-- Advertise registration to unauthorized clients only.

	if not(allow_registration) or session.type ~= "c2s_unauthed" then

		return

	end

	features:add_child(register_stream_feature);

end);

local function handle_registration_stanza(event)

	local session, stanza = event.origin, event.stanza;

	local query = stanza.tags[1];

	if stanza.attr.type == "get" then

		local reply = st.reply(stanza);

		reply:tag("query", {xmlns = "jabber:iq:register"})

			:tag("registered"):up()

			:tag("username"):text(session.username):up()

			:tag("password"):up();

		session.send(reply);

	else -- stanza.attr.type == "set"

		if query.tags[1] and query.tags[1].name == "remove" then

			local username, host = session.username, session.host;

			local old_session_close = session.close;

			session.close = function(session, ...)

				session.send(st.reply(stanza));

				return old_session_close(session, ...);

			end

			local ok, err = usermanager_delete_user(username, host);

			if not ok then

				module:log("debug", "Removing user account %s@%s failed: %s", username, host, err);

				session.close = old_session_close;

				session.send(st.error_reply(stanza, "cancel", "service-unavailable", err));

				return true;

			end

			module:log("info", "User removed their account: %s@%s", username, host);

			module:fire_event("user-deregistered", { username = username, host = host, source = "mod_register", session = session });

		else

			local username = nodeprep(query:get_child("username"):get_text());

			local password = query:get_child("password"):get_text();

			if username and password then

				if username == session.username then

					if usermanager_set_password(username, password, session.host) then

						session.send(st.reply(stanza));

					else

						-- TODO unable to write file, file may be locked, etc, what's the correct error?

						session.send(st.error_reply(stanza, "wait", "internal-server-error"));

					end

				else

					session.send(st.error_reply(stanza, "modify", "bad-request"));

				end

			else

				session.send(st.error_reply(stanza, "modify", "bad-request"));

			end

		end

	end

	return true;

end

module:hook("iq/self/jabber:iq:register:query", handle_registration_stanza);

if compat then

	module:hook("iq/host/jabber:iq:register:query", function (event)

		local session, stanza = event.origin, event.stanza;

		if session.type == "c2s" and jid_bare(stanza.attr.to) == session.host then

			return handle_registration_stanza(event);

		end

	end);

end

local function parse_response(query)

	local form = query:get_child("x", "jabber:x:data");

	if form then

		return registration_form:data(form);

	else

		local data = {};

		local errors = {};

		for _, field in ipairs(registration_form) do

			local name, required = field.name, field.required;

			if field_map[name] then

				data[name] = query:get_child_text(name);

				if (not data[name] or #data[name] == 0) and required then

					errors[name] = "Required value missing";

				end

			end

		end

		if next(errors) then

			return data, errors;

		end

		return data;

	end

end

local recent_ips = {};

local min_seconds_between_registrations = module:get_option("min_seconds_between_registrations");

local whitelist_only = module:get_option("whitelist_registration_only");

local whitelisted_ips = module:get_option("registration_whitelist") or { "127.0.0.1", "::1" };

local blacklisted_ips = module:get_option("registration_blacklist") or {};

for _, ip in ipairs(whitelisted_ips) do whitelisted_ips[ip] = true; end

for _, ip in ipairs(blacklisted_ips) do blacklisted_ips[ip] = true; end

local function get_file(name)

	local file = io.open(name, "rb")

	local data = file:read("*all")

	file:close()

	return data

end

local function get_captcha()

	local cap = captcha.new();

	math.randomseed(os_time());

	local cid = tostring(math.random(1000, 90000)); -- random cid used for cap name

	cap:font(config.font);

	cap:scribble();

	captcha_ids[cid] = cap:write(string.format("%s/%s.png", config.dir, cid)):lower();

	timer.add_task(config.timeout, function() delete_captcha(cid) end); -- Add new function to use arguments. Is there any other way in lua? Or it even works?

	return cid

end

module:hook("stanza/iq/jabber:iq:register:query", function(event)

	local session, stanza = event.origin, event.stanza;

	if not(allow_registration) or session.type ~= "c2s_unauthed" then

		session.send(st.error_reply(stanza, "cancel", "service-unavailable"));

	else

		local query = stanza.tags[1];

		if stanza.attr.type == "get" then

			local reply = st.reply(stanza):query("jabber:iq:register");

			-- TODO: Move this in standalone function

			local challenge = get_captcha()

			local captcha_data = get_file(config.dir.."/"..challenge..".png")

			local captcha_sha = sha1(captcha_data, true) -- omg

			local captcha_base64 = base64(captcha_data) -- lol wut

			xml = registration_form:form(({FORM_TYPE = "urn:xmpp:captcha",

				from = session.host,

				ocr = {{ 

					type = "image/png",

					uri = string.format("cid:sha1+%s@bob.xmpp.org", captcha_sha) 

				}};

				url = string.format("http://%s:5280/%s/%s", session.host, config.web_path, challenge);

				captcha_text = "If you can't see an image, follow link below";

				challenge = challenge;

				sid = "1";

			}));

			data = st.stanza("data", 

				{xmlns = "urn:xmpp:bob", 

				cid = string.format("sha1+%s@bob.xmpp.org", captcha_sha), 

				type = "image/png", 

				["max-age"] = config.timeout})

			:text(captcha_base64);

			reply = reply:add_child(xml);

			reply = reply:add_child(data);

			session.send(reply);

		elseif stanza.attr.type == "set" then

			if query.tags[1] and query.tags[1].name == "remove" then

				session.send(st.error_reply(stanza, "auth", "registration-required"));

			else

				local data, errors = parse_response(query);

				if errors then

					session.send(st.error_reply(stanza, "modify", "not-acceptable"));

				else

					-- Check that the user is not blacklisted or registering too often

					if not session.ip then

						module:log("debug", "User's IP not known; can't apply blacklist/whitelist");

					elseif blacklisted_ips[session.ip] or (whitelist_only and not whitelisted_ips[session.ip]) then

						session.send(st.error_reply(stanza, "cancel", "not-acceptable", "You are not allowed to register an account."));

						return true;

					elseif min_seconds_between_registrations and not whitelisted_ips[session.ip] then

						if not recent_ips[session.ip] then

							recent_ips[session.ip] = { time = os_time(), count = 1 };

						else

							local ip = recent_ips[session.ip];

							ip.count = ip.count + 1;

							if os_time() - ip.time < min_seconds_between_registrations then

								ip.time = os_time();

								session.send(st.error_reply(stanza, "wait", "not-acceptable"));

								return true;

							end

							ip.time = os_time();

						end

					end

					local host = module.host;

					local ocr = data.ocr:lower();

					local challenge = data.challenge;

					local username, password = nodeprep(data.username), data.password;

					data.username, data.password = nil, nil; 

					if challenge == nil or captcha_ids[challenge] == nil then

						session.send(st.error_reply(stanza, "modify", "not-acceptable", "Captcha id is invalid or it has expired"));

						delete_captcha(challenge);

						return true;

					elseif ocr ~= captcha_ids[challenge] then

						session.send(st.error_reply(stanza, "modify", "not-acceptable", "Invalid captcha text"));

						delete_captcha(challenge);

						return true;

					end

					if not username or username == "" then

						session.send(st.error_reply(stanza, "modify", "not-acceptable", "The requested username is invalid."));

						delete_captcha(challenge);

						return true;

					end

					local user = { username = username , host = host, allowed = true }

					module:fire_event("user-registering", user);

					if not user.allowed then

						delete_captcha(challenge);

						session.send(st.error_reply(stanza, "modify", "not-acceptable", "The requested username is forbidden."));

					elseif usermanager_user_exists(username, host) then

						delete_captcha(challenge)

						session.send(st.error_reply(stanza, "cancel", "conflict", "The requested username already exists."));

					else

						-- TODO unable to write file, file may be locked, etc, what's the correct error?

						local error_reply = st.error_reply(stanza, "wait", "internal-server-error", "Failed to write data to disk.");

						if usermanager_create_user(username, password, host) then

							if next(data) and not account_details:set(username, data) then

								delete_captcha(challenge);

								usermanager_delete_user(username, host);

								session.send(error_reply);

								return true;

							end

							session.send(st.reply(stanza)); -- user created!

							module:log("info", "User account created: %s@%s", username, host);

							module:fire_event("user-registered", {

								username = username, host = host, source = "mod_register",

								session = session });

						else

							delete_captcha(challenge);

							session.send(error_reply);

						end

					end

				end

			end

		end

	end

	return true;

end);

function string:split(sep)

	local sep, fields = sep or ":", {}

	local pattern = string.format("([^%s]+)", sep)

	self:gsub(pattern, function(c) fields[#fields+1] = c end)

	return fields

end

function handle_http_request(event) 

	local request = event.request;

	local path = request.path;

	local cid = path:split("/")[2];

	if cid == nil or captcha_ids[cid] == nil then

		return nil;

	end