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

local pairs = pairs;

local tostring = tostring;

local type = type;

local hosts = hosts;

local bare_sessions = prosody.bare_sessions;

local datamanager = require "util.datamanager"

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

local st = require "util.stanza";

local _ENV = nil;

local save_roster; -- forward declaration

local 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

local 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

local function roster_push(username, host, jid)

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

	if roster then

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

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

		stanza:tag("query", {xmlns = "jabber:iq:roster", ver = tostring(roster[false].version or "1")  });

		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

local function roster_metadata(roster, err)

	local metadata = roster[false];

	if not metadata then

		metadata = { broken = err or nil };

		roster[false] = metadata;

	end

	if roster.pending and type(roster.pending.subscription) ~= "string" then

		metadata.pending = roster.pending;

		roster.pending = nil;

	elseif not metadata.pending then

		metadata.pending = {};

	end

	return metadata;

end

local function load_roster(username, host)

	local jid = username.."@"..host;

	log("debug", "load_roster: asked for: %s", jid);

	local user = bare_sessions[jid];

	local roster;

	if user then

		roster = user.roster;

		if roster then return roster; end

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

	else -- Attempt to load roster for non-loaded user

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

	end

	local data, err = datamanager.load(username, host, "roster");

	roster = data or {};

	if user then user.roster = roster; end

	roster_metadata(roster, err);

	if roster[jid] then

		roster[jid] = nil;

		log("warn", "roster for %s has a self-contact", jid);

	end

	if not err then

		hosts[host].events.fire_event("roster-load", { username = username, host = host, roster = roster });

	end

	return roster, err;

end

function save_roster(username, host, roster)

	if not um_user_exists(username, host) then

		log("debug", "not saving roster for %s@%s: the user doesn't exist", username, host);

		return nil;

	end

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

	if not roster then

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

		--if not roster then

		--	--roster = load_roster(username, host);

		--	return true; -- roster unchanged, no reason to save

		--end

	end

	if roster then

		local metadata = roster_metadata(roster);

		if metadata.version ~= true then

			metadata.version = (metadata.version or 0) + 1;

		end

		if metadata.broken then return nil, "Not saving broken roster" end

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

	end

	log("warn", "save_roster: user had no roster to save");

	return nil;

end

local 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 save_roster(username, host, roster);

	end

end

local is_contact_pending_out -- forward declaration

local 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 save_roster(username, host, roster);

	end

end

local is_contact_pending_in -- forward declaration

local 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[false].pending[jid] = nil;

		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 save_roster(username, host, roster);

	end

end

local function _get_online_roster_subscription(jidA, jidB)

	local user = bare_sessions[jidA];

	local item = user and (user.roster[jidB] or { subscription = "none" });

	return item and item.subscription;

end

local function is_contact_subscribed(username, host, jid)

	do

		local selfjid = username.."@"..host;

		local user_subscription = _get_online_roster_subscription(selfjid, jid);

		if user_subscription then return (user_subscription == "both" or user_subscription == "from"); end

		local contact_subscription = _get_online_roster_subscription(jid, selfjid);

		if contact_subscription then return (contact_subscription == "both" or contact_subscription == "to"); end

	end

	local roster, err = load_roster(username, host);

	local item = roster[jid];

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

end

function is_contact_pending_in(username, host, jid)

	local roster = load_roster(username, host);

	return roster[false].pending[jid];

end

local function set_contact_pending_in(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

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

		return; -- false

	end

	roster[false].pending[jid] = true;

	return save_roster(username, host, 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

local 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 %s@%s.roster[%q].ask=subscribe", username, host, jid);

	return save_roster(username, host, roster);

end

local 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 save_roster(username, host, roster);

end

local 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 not item then -- FIXME should roster item be auto-created?

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

			roster[jid] = item;

		end

		if item.subscription == "none" then

			item.subscription = "from";

		else -- subscription == to

			item.subscription = "both";

		end

		roster[false].pending[jid] = nil;

		return save_roster(username, host, roster);

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

end

local function unsubscribed(username, host, jid)

	local roster = load_roster(username, host);

	local item = roster[jid];

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

	if pending then

		roster[false].pending[jid] = nil;

	end

	if item then

		if item.subscription == "from" then

			item.subscription = "none";

		elseif item.subscription == "both" then

			item.subscription = "to";

		end

	end

	return success, pending, subscribed;

end

local 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 save_roster(username, host, 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 save_roster(username, host, roster);

	end

end]]

return {

	add_to_roster = add_to_roster;

	remove_from_roster = remove_from_roster;

	roster_push = roster_push;

	load_roster = load_roster;

	save_roster = save_roster;

	process_inbound_subscription_approval = process_inbound_subscription_approval;

	process_inbound_subscription_cancellation = process_inbound_subscription_cancellation;

	process_inbound_unsubscribe = process_inbound_unsubscribe;

	is_contact_subscribed = is_contact_subscribed;

	is_contact_pending_in = is_contact_pending_in;

	set_contact_pending_in = set_contact_pending_in;

	is_contact_pending_out = is_contact_pending_out;

	set_contact_pending_out = set_contact_pending_out;

	unsubscribe = unsubscribe;

	subscribed = subscribed;

	unsubscribed = unsubscribed;

	process_outbound_subscription_request = process_outbound_subscription_request;

};