-- XEP-0313: Message Archive Management for Prosody

-- Copyright (C) 2011-2012 Kim Alvefur

--

-- This file is MIT/X11 licensed.

local xmlns_mam     = "urn:xmpp:mam:tmp";

local xmlns_delay   = "urn:xmpp:delay";

local xmlns_forward = "urn:xmpp:forward:0";

local st = require "util.stanza";

local rsm = module:require "mod_mam/rsm";

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

local jid_split = require "util.jid".split;

local jid_prep = require "util.jid".prep;

local host = module.host;

local serialize, deserialize = require"util.json".encode, require"util.json".decode;

local unpack = unpack;

local tostring = tostring;

local time_now = os.time;

local t_insert = table.insert;

local m_min = math.min;

local timestamp, timestamp_parse = require "util.datetime".datetime, require "util.datetime".parse;

local default_max_items, max_max_items = 20, module:get_option_number("max_archive_query_results", 50);

--local rooms_to_archive = module:get_option_set("rooms_to_archive",{});

local sql, setsql, getsql = {};

do -- SQL stuff

local dburi;

local connection;

local connections = module:shared "/*/sql/connection-cache";

local build_url = require"socket.url".build;

local resolve_relative_path = require "core.configmanager".resolve_relative_path;

local params = module:get_option("mam_sql", module:get_option("sql"));

local function db2uri(params)

	return build_url{

		scheme = params.driver,

		user = params.username,

		password = params.password,

		host = params.host,

		port = params.port,

		path = params.database,

	};

end

local function test_connection()

	if not connection then return nil; end

	if connection:ping() then

		return true;

	else

		module:log("debug", "Database connection closed");

		connection = nil;

		connections[dburi] = nil;

	end

end

local function connect()

	if not test_connection() then

		prosody.unlock_globals();

		local dbh, err = DBI.Connect(

			params.driver, params.database,

			params.username, params.password,

			params.host, params.port

		);

		prosody.lock_globals();

		if not dbh then

			module:log("debug", "Database connection failed: %s", tostring(err));

			return nil, err;

		end

		module:log("debug", "Successfully connected to database");

		dbh:autocommit(false); -- don't commit automatically

		connection = dbh;

		connections[dburi] = dbh;

	end

	return connection;

end

do -- process options to get a db connection

	local ok;

	prosody.unlock_globals();

	ok, DBI = pcall(require, "DBI");

	if not ok then

		package.loaded["DBI"] = {};

		module:log("error", "Failed to load the LuaDBI library for accessing SQL databases: %s", DBI);

		module:log("error", "More information on installing LuaDBI can be found at http://prosody.im/doc/depends#luadbi");

	end

	prosody.lock_globals();

	if not ok or not DBI.Connect then

		return; -- Halt loading of this module

	end

	params = params or { driver = "SQLite3" };

	if params.driver == "SQLite3" then

		params.database = resolve_relative_path(prosody.paths.data or ".", params.database or "prosody.sqlite");

	end

	assert(params.driver and params.database, "Both the SQL driver and the database need to be specified");

	dburi = db2uri(params);

	connection = connections[dburi];

	assert(connect());

end

function getsql(sql, ...)

	if params.driver == "PostgreSQL" then

		sql = sql:gsub("`", "\"");

	end

	-- do prepared statement stuff

	local stmt, err = connection:prepare(sql);

	if not stmt and not test_connection() then error("connection failed"); end

	if not stmt then module:log("error", "QUERY FAILED: %s %s", err, debug.traceback()); return nil, err; end

	-- run query

	local ok, err = stmt:execute(...);

	if not ok and not test_connection() then error("connection failed"); end

	if not ok then return nil, err; end

	return stmt;

end

function setsql(sql, ...)

	local stmt, err = getsql(sql, ...);

	if not stmt then return stmt, err; end

	return stmt:affected();

end

function sql.rollback(...)

	if connection then connection:rollback(); end -- FIXME check for rollback error?

	return ...;

end

function sql.commit(...)

	if not connection:commit() then return nil, "SQL commit failed"; end

	return ...;

end

end

local archive_store = "archive2";

-- Handle archive queries

module:hook("iq/bare/"..xmlns_mam..":query", function(event)

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

	local room = jid_split(stanza.attr.to);

	local query = stanza.tags[1];

	local room_obj = hosts[module.host].modules.muc.rooms[jid_bare(stanza.attr.to)];

	if not room_obj then

		return -- FIXME not found

	end

	local from = jid_bare(stanza.attr.from);

	if room_obj._affiliations[from] == "outcast"

		or room_obj._data.members_only and not room_obj._affiliations[from] then

		return -- FIXME unauth

	end

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

		local qid = query.attr.queryid;

		-- Search query parameters

		local qwith = query:get_child_text("with");

		local qstart = query:get_child_text("start");

		local qend = query:get_child_text("end");

		local qset = rsm.get(query);

		module:log("debug", "Archive query, id %s with %s from %s until %s)",

			tostring(qid), qwith or "anyone", qstart or "the dawn of time", qend or "now");

		if qstart or qend then -- Validate timestamps

			local vstart, vend = (qstart and timestamp_parse(qstart)), (qend and timestamp_parse(qend))

			if (qstart and not vstart) or (qend and not vend) then

				origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid timestamp"))

				return true

			end

			qstart, qend = vstart, vend;

		end

		local qres;

		if qwith then -- Validate the 'with' jid

			local pwith = qwith and jid_prep(qwith);

			if pwith and not qwith then -- it failed prepping

				origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid JID"))

				return true

			end

			local _, _, resource = jid_split(qwith);

			qwith = jid_bare(pwith);

			qres = resource;

		end

		-- RSM stuff

		local qmax = m_min(qset and qset.max or default_max_items, max_max_items);

		local first, last;

		local n = 0;

		local sql_query = ([[

		SELECT `id`, `when`, `stanza`

		FROM `prosodyarchive`

		WHERE `host` = ? AND `user` = ? AND `store` = ?

		AND `when` BETWEEN ? AND ?

		%s

		AND `id` > ?

		LIMIT ?;

		]]):format(qres and [[AND `resource` = ?]] or "")

		local p = {

			host, room, archive_store,

			qstart or 0, qend or time_now(),

			qset and tonumber(qset.after) or 0,

			qmax

		};

		if qres then

			t_insert(p, 6, qres);

		end

		module:log("debug", "getsql(sql_query, "..table.concat(p, ", "));

		local data, err = getsql(sql_query, unpack(p));

		if not data then

			origin.send(st.error_reply(stanza, "cancel", "internal-server-error", "Error loading archive: "..tostring(err)));

			return true

		end

		for item in data:rows() do

			local id, when, orig_stanza = unpack(item);

			--module:log("debug", "id is %s", id);

			local fwd_st = st.message{ to = stanza.attr.from, from = stanza.attr.to }

				:tag("result", { xmlns = xmlns_mam, queryid = qid, id = id }):up()

				:tag("forwarded", { xmlns = xmlns_forward })

					:tag("delay", { xmlns = xmlns_delay, stamp = timestamp(when) }):up();

			orig_stanza = st.deserialize(deserialize(orig_stanza));

			orig_stanza.attr.xmlns = "jabber:client";

			fwd_st:add_child(orig_stanza);

			origin.send(fwd_st);

			last = id;

			n = n + 1;

			if not first then

				first = id;

			end

		end

		-- That's all folks!

		module:log("debug", "Archive query %s completed", tostring(qid));

		local reply = st.reply(stanza);

		if last then

			-- This is a bit redundant, isn't it?

			reply:query(xmlns_mam):add_child(rsm.generate{first = first, last = last, count = n});

		end

		origin.send(reply);

		return true

	end

end);

-- Handle messages

local function message_handler(event)

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

	local orig_type = stanza.attr.type or "normal";

	local orig_to = stanza.attr.to;

	local orig_from = stanza.attr.from;

	-- Still needed?

	if not orig_from then

		orig_from = origin.full_jid;

	end

	-- Only store groupchat messages

	if not (orig_type == "groupchat" and (stanza:get_child("body") or stanza:get_child("subject"))) then

		return;

	end

	local room = jid_split(orig_to);

	local room_obj = hosts[host].modules.muc.rooms[orig_to]

	if not room_obj then return end

	local when = time_now();

	local stanza = st.clone(stanza); -- Private copy

	--stanza.attr.to = nil;

	local nick = room_obj._jid_nick[orig_from];

	if not nick then return end

	stanza.attr.from = nick;

	local _, _, nick = jid_split(nick);

	-- And stash it

		local ok, err = setsql([[

		INSERT INTO `prosodyarchive`

		(`host`, `user`, `store`, `when`, `resource`, `stanza`)

		VALUES (?, ?, ?, ?, ?, ?);

		]], host, room, archive_store, when, nick, serialize(st.preserialize(stanza)))

		if ok then

			sql.commit();

		else

			module:log("error", "SQL error: %s", err);

			sql.rollback();

		end

	--[[ This was dropped from the spec

	if ok then

		stanza:tag("archived", { xmlns = xmlns_mam, by = host, id = id }):up();

	end

	--]]

end

module:hook("message/bare", message_handler, 2);

module:add_feature(xmlns_mam);