local tonumber, tostring = tonumber, tostring;

local ipairs, pairs, print, next= ipairs, pairs, print, next;

local collectgarbage = collectgarbage;

local m_random = import("math", "random");

local format = import("string", "format");

local hosts = hosts;

local sessions = sessions;

local modulemanager = require "core.modulemanager";

local log = require "util.logger".init("sessionmanager");

local error = error;

local uuid_generate = require "util.uuid".generate;

local rm_load_roster = require "core.rostermanager".load_roster;

local newproxy = newproxy;

local getmetatable = getmetatable;

module "sessionmanager"

local open_sessions = 0;

function new_session(conn)

	local session = { conn = conn,  priority = 0, type = "c2s_unauthed" };

	if true then

		session.trace = newproxy(true);

		getmetatable(session.trace).__gc = function () open_sessions = open_sessions - 1; print("Session got collected, now "..open_sessions.." sessions are allocated") end;

	end

	open_sessions = open_sessions + 1;

	local w = conn.write;

	session.send = function (t) w(tostring(t)); end

	return session;

end

function destroy_session(session)

	(session.log or log)("info", "Destroying session");

	if session.host and session.username then

		if session.resource then

			hosts[session.host].sessions[session.username].sessions[session.resource] = nil;

		end

		if hosts[session.host] and hosts[session.host].sessions[session.username] then

			if not next(hosts[session.host].sessions[session.username].sessions) then

				log("debug", "All resources of %s are now offline", session.username);

				hosts[session.host].sessions[session.username] = nil;

			end

		end

	end

	session.conn = nil;

	session.disconnect = nil;

	for k in pairs(session) do

		if k ~= "trace" then

			session[k] = nil;

		end

	end

end

function make_authenticated(session, username)

	session.username = username;

	if session.type == "c2s_unauthed" then

		session.type = "c2s";

	end

	return true;

end

-- returns true, nil on success

-- returns nil, err_type, err, err_message on failure

function bind_resource(session, resource)

	if not session.username then return nil, "auth", "not-authorized", "Cannot bind resource before authentication"; end

	if session.resource then return nil, "cancel", "already-bound", "Cannot bind multiple resources on a single connection"; end

	-- We don't support binding multiple resources

	resource = resource or uuid_generate();

	--FIXME: Randomly-generated resources must be unique per-user, and never conflict with existing

	if not hosts[session.host].sessions[session.username] then

		hosts[session.host].sessions[session.username] = { sessions = {} };

	else

		if hosts[session.host].sessions[session.username].sessions[resource] then

			-- Resource conflict

			return nil, "cancel", "conflict", "Resource already exists"; -- TODO kick old resource

		end

	end

	session.resource = resource;

	session.full_jid = session.username .. '@' .. session.host .. '/' .. resource;

	hosts[session.host].sessions[session.username].sessions[resource] = session;

	session.roster = rm_load_roster(session.username, session.host);

	return true;

end

function streamopened(session, attr)

						local send = session.send;

						session.host = attr.to or error("Client failed to specify destination hostname");

			                        session.version = tonumber(attr.version) or 0;

			                        session.streamid = m_random(1000000, 99999999);

			                        print(session, session.host, "Client opened stream");

			                        send("<?xml version='1.0'?>");

			                        send(format("<stream:stream xmlns='jabber:client' xmlns:stream='http://etherx.jabber.org/streams' id='%s' from='%s' version='1.0'>", session.streamid, session.host));

						local features = {};

						modulemanager.fire_event("stream-features", session, features);

						send("<stream:features>");

						for _, feature in ipairs(features) do

							send(tostring(feature));

						end

        			                send("</stream:features>");

						log("info", "Stream opened successfully");

						session.notopen = nil;

end

function send_to_available_resources(user, host, stanza)

	local count = 0;

	local to = stanza.attr.to;

	stanza.attr.to = nil;

	local h = hosts[host];

	if h and h.type == "local" then

		local u = h.sessions[user];

		if u then

			for k, session in pairs(u.sessions) do

				if session.presence then

					session.send(stanza);

					count = count + 1;

				end

			end

		end

	end

	stanza.attr.to = to;

	return count;

end

return _M;