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

local setmetatable = setmetatable;

local format = string.format;

local loadfile, setfenv, pcall = loadfile, setfenv, pcall;

local pairs, ipairs = pairs, ipairs;

local hosts = hosts;

local datamanager = require "util.datamanager"

local st = require "util.stanza";

module "rostermanager"

function add_to_roster(session, jid, item)

	if session.roster then

		local old_item = session.roster[jid];

		session.roster[jid] = item;

		if save_roster(session.username, session.host) then

			return true;

		else

			session.roster[jid] = old_item;

			return nil, "wait", "internal-server-error", "Unable to save roster";

		end

	else

		return nil, "auth", "not-authorized", "Session's roster not loaded";

	end

end

function remove_from_roster(session, jid)

	if session.roster then

		local old_item = session.roster[jid];

		session.roster[jid] = nil;

		if save_roster(session.username, session.host) then

			return true;

		else

			session.roster[jid] = old_item;

			return nil, "wait", "internal-server-error", "Unable to save roster";

		end

	else

		return nil, "auth", "not-authorized", "Session's roster not loaded";

	end

end

function roster_push(username, host, jid)

	if jid ~= "pending" and hosts[host] and hosts[host].sessions[username] and hosts[host].sessions[username].roster then

		local item = hosts[host].sessions[username].roster[jid];

		local stanza = st.iq({type="set"});

		stanza:tag("query", {xmlns = "jabber:iq:roster"});

		if item then

			stanza:tag("item", {jid = jid, subscription = item.subscription, name = item.name, ask = item.ask});

			for group in pairs(item.groups) do

				stanza:tag("group"):text(group):up();

			end

		else

			stanza:tag("item", {jid = jid, subscription = "remove"});

		end

		stanza:up(); -- move out from item

		stanza:up(); -- move out from stanza

		-- stanza ready

		for _, session in pairs(hosts[host].sessions[username].sessions) do

			if session.interested then

				-- FIXME do we need to set stanza.attr.to?

				session.send(stanza);

			end

		end

	end

end

function load_roster(username, host)

	log("debug", "load_roster: asked for: "..username.."@"..host);

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

		local roster = hosts[host].sessions[username].roster;

		if not roster then

			log("debug", "load_roster: loading for new user: "..username.."@"..host);

			roster = datamanager.load(username, host, "roster") or {};

			hosts[host].sessions[username].roster = roster;

		end

		return roster;

	end

	-- Attempt to load roster for non-loaded user

	log("debug", "load_roster: loading for offline user: "..username.."@"..host);

	return datamanager.load(username, host, "roster") or {};

end

function save_roster(username, host)

	log("debug", "save_roster: saving roster for "..username.."@"..host);

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

		return datamanager.store(username, host, "roster", hosts[host].sessions[username].roster);

	end

	return nil;

end

function process_inbound_subscription_approval(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	if item and item.ask then

		if item.subscription == "none" then

			item.subscription = "to";

		else -- subscription == from

			item.subscription = "both";

		end

		item.ask = nil;

		return datamanager.store(username, host, "roster", roster);

	end

end

function process_inbound_subscription_cancellation(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	local changed = nil;

	if is_contact_pending_out(username, host, jid) then

		item.ask = nil;

		changed = true;

	end

	if item then

		if item.subscription == "to" then

			item.subscription = "none";

			changed = true;

		elseif item.subscription == "both" then

			item.subscription = "from";

			changed = true;

		end

	end

	if changed then

		return datamanager.store(username, host, "roster", roster);

	end

end

function process_inbound_unsubscribe(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	local changed = nil;

	if is_contact_pending_in(username, host, jid) then

		roster.pending[jid] = nil; -- TODO maybe delete roster.pending if empty?

		changed = true;

	end

	if item then

		if item.subscription == "from" then

			item.subscription = "none";

			changed = true;

		elseif item.subscription == "both" then

			item.subscription = "to";

			changed = true;

		end

	end

	if changed then

		return datamanager.store(username, host, "roster", roster);

	end

end

function is_contact_subscribed(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	return item and (item.subscription == "from" or item.subscription == "both");

end

function is_contact_pending_in(username, host, jid)

	local roster = load_roster(username, host);

	return roster.pending and roster.pending[jid];

end

function set_contact_pending_in(username, host, jid, pending)

	local roster = load_roster(username, host);

	local item = roster[jid];

	if item and (item.subscription == "from" or item.subscription == "both") then

		return; -- false

	end

	if not roster.pending then roster.pending = {}; end

	roster.pending[jid] = true;

	return datamanager.store(username, host, "roster", roster);

end

function is_contact_pending_out(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	return item and item.ask;

end

function set_contact_pending_out(username, host, jid) -- subscribe

	local roster = load_roster(username, host);

	local item = roster[jid];

	if item and (item.ask or item.subscription == "to" or item.subscription == "both") then

		return true;

	end

	if not item then

		item = {subscription = "none", groups = {}};

		roster[jid] = item;

	end

	item.ask = "subscribe";

	log("debug", "set_contact_pending_out: saving roster; set "..username.."@"..host..".roster["..jid.."].ask=subscribe");

	return datamanager.store(username, host, "roster", roster);

end

function unsubscribe(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	if not item then return false; end

	if (item.subscription == "from" or item.subscription == "none") and not item.ask then

		return true;

	end

	item.ask = nil;

	if item.subscription == "both" then

		item.subscription = "from";

	elseif item.subscription == "to" then

		item.subscription = "none";

	end

	return datamanager.store(username, host, "roster", roster);

end

function subscribed(username, host, jid)

	if is_contact_pending_in(username, host, jid) then

		local roster = load_roster(username, host);

		local item = roster[jid];

		if item.subscription == "none" then

			item.subscription = "from";

		else -- subscription == to

			item.subscription = "both";

		end

		roster.pending[jid] = nil;

		-- TODO maybe remove roster.pending if empty

		return datamanager.store(username, host, "roster", roster);

	end -- TODO else implement optional feature pre-approval (ask = subscribed)

end

function unsubscribed(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	local pending = is_contact_pending_in(username, host, jid);

	local changed = nil;

	if is_contact_pending_in(username, host, jid) then

		roster.pending[jid] = nil; -- TODO maybe delete roster.pending if empty?

		changed = true;

	end

	if item then

		if item.subscription == "from" then

			item.subscription = "none";

			changed = true;

		elseif item.subscription == "both" then

			item.subscription = "to";

			changed = true;

		end

	end

	if changed then

		return datamanager.store(username, host, "roster", roster);

	end

end

function process_outbound_subscription_request(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	if item and (item.subscription == "none" or item.subscription == "from") then

		item.ask = "subscribe";

		return datamanager.store(username, host, "roster", roster);

	end

end

--[[function process_outbound_subscription_approval(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

	if item and (item.subscription == "none" or item.subscription == "from" then

		item.ask = "subscribe";

		return datamanager.store(username, host, "roster", roster);

	end

end]]

return _M;